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2.
Nat Immunol ; 18(9): 1004-1015, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28759001

RESUMEN

Avoiding destruction by immune cells is a hallmark of cancer, yet how tumors ultimately evade control by natural killer (NK) cells remains incompletely defined. Using global transcriptomic and flow-cytometry analyses and genetically engineered mouse models, we identified the cytokine-TGF-ß-signaling-dependent conversion of NK cells (CD49a-CD49b+Eomes+) into intermediate type 1 innate lymphoid cell (intILC1) (CD49a+CD49b+Eomes+) populations and ILC1 (CD49a+CD49b-Eomesint) populations in the tumor microenvironment. Strikingly, intILC1s and ILC1s were unable to control local tumor growth and metastasis, whereas NK cells favored tumor immunosurveillance. Experiments with an antibody that neutralizes the cytokine TNF suggested that escape from the innate immune system was partially mediated by TNF-producing ILC1s. Our findings provide new insight into the plasticity of group 1 ILCs in the tumor microenvironment and suggest that the TGF-ß-driven conversion of NK cells into ILC1s is a previously unknown mechanism by which tumors escape surveillance by the innate immune system.


Asunto(s)
Reprogramación Celular/inmunología , Fibrosarcoma/inmunología , Neoplasias Gastrointestinales/inmunología , Tumores del Estroma Gastrointestinal/inmunología , Inmunidad Innata/inmunología , Células Asesinas Naturales/inmunología , Neoplasias Experimentales/inmunología , Escape del Tumor/inmunología , Animales , Estudios de Casos y Controles , Línea Celular Tumoral , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Perfilación de la Expresión Génica , Humanos , Células Asesinas Naturales/citología , Linfocitos/citología , Linfocitos/inmunología , Ratones , Análisis de Secuencia de ARN , Transducción de Señal , Factor de Crecimiento Transformador beta/inmunología
3.
Nature ; 615(7953): 712-719, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36922590

RESUMEN

Mitochondria are critical to the governance of metabolism and bioenergetics in cancer cells1. The mitochondria form highly organized networks, in which their outer and inner membrane structures define their bioenergetic capacity2,3. However, in vivo studies delineating the relationship between the structural organization of mitochondrial networks and their bioenergetic activity have been limited. Here we present an in vivo structural and functional analysis of mitochondrial networks and bioenergetic phenotypes in non-small cell lung cancer (NSCLC) using an integrated platform consisting of positron emission tomography imaging, respirometry and three-dimensional scanning block-face electron microscopy. The diverse bioenergetic phenotypes and metabolic dependencies we identified in NSCLC tumours align with distinct structural organization of mitochondrial networks present. Further, we discovered that mitochondrial networks are organized into distinct compartments within tumour cells. In tumours with high rates of oxidative phosphorylation (OXPHOSHI) and fatty acid oxidation, we identified peri-droplet mitochondrial networks wherein mitochondria contact and surround lipid droplets. By contrast, we discovered that in tumours with low rates of OXPHOS (OXPHOSLO), high glucose flux regulated perinuclear localization of mitochondria, structural remodelling of cristae and mitochondrial respiratory capacity. Our findings suggest that in NSCLC, mitochondrial networks are compartmentalized into distinct subpopulations that govern the bioenergetic capacity of tumours.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Metabolismo Energético , Neoplasias Pulmonares , Mitocondrias , Humanos , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/ultraestructura , Ácidos Grasos/metabolismo , Glucosa/metabolismo , Gotas Lipídicas/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/ultraestructura , Microscopía Electrónica , Mitocondrias/metabolismo , Mitocondrias/ultraestructura , Fosforilación Oxidativa , Fenotipo , Tomografía de Emisión de Positrones
4.
Nature ; 598(7880): 321-326, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34552245

RESUMEN

Mounting evidence shows that dopamine in the striatum is critically involved in reward-based reinforcement learning1,2. However, it remains unclear how dopamine reward signals influence the entorhinal-hippocampal circuit, another brain network that is crucial for learning and memory3-5. Here, using cell-type-specific electrophysiological recording6, we show that dopamine signals from the ventral tegmental area and substantia nigra control the encoding of cue-reward association rules in layer 2a fan cells of the lateral entorhinal cortex (LEC). When mice learned novel olfactory cue-reward associations using a pre-learned association rule, spike representations of LEC fan cells grouped newly learned rewarded cues with a pre-learned rewarded cue, but separated them from a pre-learned unrewarded cue. Optogenetic inhibition of fan cells impaired the learning of new associations while sparing the retrieval of pre-learned memory. Using fibre photometry, we found that dopamine sends novelty-induced reward expectation signals to the LEC. Inhibition of LEC dopamine signals disrupted the associative encoding of fan cells and impaired learning performance. These results suggest that LEC fan cells represent a cognitive map of abstract task rules, and that LEC dopamine facilitates the incorporation of new memories into this map.


Asunto(s)
Dopamina/metabolismo , Corteza Entorrinal/citología , Corteza Entorrinal/fisiología , Memoria/fisiología , Animales , Anticipación Psicológica , Señales (Psicología) , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Células Piramidales/metabolismo , Recompensa
5.
EMBO J ; 41(8): e108587, 2022 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-35023587

RESUMEN

The apoptotic executioner protein BAX and the dynamin-like protein DRP1 co-localize at mitochondria during apoptosis to mediate mitochondrial permeabilization and fragmentation. However, the molecular basis and functional consequences of this interplay remain unknown. Here, we show that BAX and DRP1 physically interact, and that this interaction is enhanced during apoptosis. Complex formation between BAX and DRP1 occurs exclusively in the membrane environment and requires the BAX N-terminal region, but also involves several other BAX surfaces. Furthermore, the association between BAX and DRP1 enhances the membrane activity of both proteins. Forced dimerization of BAX and DRP1 triggers their activation and translocation to mitochondria, where they induce mitochondrial remodeling and permeabilization to cause apoptosis even in the absence of apoptotic triggers. Based on this, we propose that DRP1 can promote apoptosis by acting as noncanonical direct activator of BAX through physical contacts with its N-terminal region.


Asunto(s)
Apoptosis , Dinaminas , Apoptosis/fisiología , Dinaminas/genética , Dinaminas/metabolismo , Mitocondrias/metabolismo , Proteína X Asociada a bcl-2/genética , Proteína X Asociada a bcl-2/metabolismo
6.
Cell ; 145(6): 863-74, 2011 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-21640374

RESUMEN

Metabolites in the kynurenine pathway, generated by tryptophan degradation, are thought to play an important role in neurodegenerative disorders, including Alzheimer's and Huntington's diseases. In these disorders, glutamate receptor-mediated excitotoxicity and free radical formation have been correlated with decreased levels of the neuroprotective metabolite kynurenic acid. Here, we describe the synthesis and characterization of JM6, a small-molecule prodrug inhibitor of kynurenine 3-monooxygenase (KMO). Chronic oral administration of JM6 inhibits KMO in the blood, increasing kynurenic acid levels and reducing extracellular glutamate in the brain. In a transgenic mouse model of Alzheimer's disease, JM6 prevents spatial memory deficits, anxiety-related behavior, and synaptic loss. JM6 also extends life span, prevents synaptic loss, and decreases microglial activation in a mouse model of Huntington's disease. These findings support a critical link between tryptophan metabolism in the blood and neurodegeneration, and they provide a foundation for treatment of neurodegenerative diseases.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Huntington/tratamiento farmacológico , Ácido Quinurénico/análisis , Quinurenina 3-Monooxigenasa/antagonistas & inhibidores , Sulfonamidas/uso terapéutico , Tiazoles/uso terapéutico , Administración Oral , Enfermedad de Alzheimer/fisiopatología , Animales , Química Encefálica , Modelos Animales de Enfermedad , Femenino , Humanos , Ácido Quinurénico/sangre , Masculino , Ratones , Ratones Transgénicos , Sulfonamidas/administración & dosificación , Tiazoles/administración & dosificación
8.
Pharmacol Rev ; 75(6): 1140-1166, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37328294

RESUMEN

Pharmacological agents used to treat or manage diseases can modify the level of heat strain experienced by chronically ill and elderly patients via different mechanistic pathways. Human thermoregulation is a crucial homeostatic process that maintains body temperature within a narrow range during heat stress through dry (i.e., increasing skin blood flow) and evaporative (i.e., sweating) heat loss, as well as active inhibition of thermogenesis, which is crucial to avoid overheating. Medications can independently and synergistically interact with aging and chronic disease to alter homeostatic responses to rising body temperature during heat stress. This review focuses on the physiologic changes, with specific emphasis on thermolytic processes, associated with medication use during heat stress. The review begins by providing readers with a background of the global chronic disease burden. Human thermoregulation and aging effects are then summarized to give an understanding of the unique physiologic changes faced by older adults. The effects of common chronic diseases on temperature regulation are outlined in the main sections. Physiologic impacts of common medications used to treat these diseases are reviewed in detail, with emphasis on the mechanisms by which these medications alter thermolysis during heat stress. The review concludes by providing perspectives on the need to understand the effects of medication use in hot environments, as well as a summary table of all clinical considerations and research needs of the medications included in this review. SIGNIFICANCE STATEMENT: Long-term medications modulate thermoregulatory function, resulting in excess physiological strain and predisposing patients to adverse health outcomes during prolonged exposures to extreme heat during rest and physical work (e.g., exercise). Understanding the medication-specific mechanisms of altered thermoregulation has importance in both clinical and research settings, paving the way for work toward refining current medication prescription recommendations and formulating mitigation strategies for adverse drug effects in the heat in chronically ill patients.


Asunto(s)
Calentamiento Global , Calor , Humanos , Anciano , Regulación de la Temperatura Corporal/fisiología , Temperatura Corporal/fisiología , Enfermedad Crónica
9.
Immunity ; 45(2): 333-45, 2016 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-27533014

RESUMEN

Many pathogens, including Plasmodium spp., exploit the interaction of programmed death-1 (PD-1) with PD-1-ligand-1 (PD-L1) to "deactivate" T cell functions, but the role of PD-L2 remains unclear. We studied malarial infections to understand the contribution of PD-L2 to immunity. Here we have shown that higher PD-L2 expression on blood dendritic cells, from Plasmodium falciparum-infected individuals, correlated with lower parasitemia. Mechanistic studies in mice showed that PD-L2 was indispensable for establishing effective CD4(+) T cell immunity against malaria, because it not only inhibited PD-L1 to PD-1 activity but also increased CD3 and inducible co-stimulator (ICOS) expression on T cells. Importantly, administration of soluble multimeric PD-L2 to mice with lethal malaria was sufficient to dramatically improve immunity and survival. These studies show immuno-regulation by PD-L2, which has the potential to be translated into an effective treatment for malaria and other diseases where T cell immunity is ineffective or short-lived due to PD-1-mediated signaling.


Asunto(s)
Antígeno B7-H1/metabolismo , Linfocitos T CD4-Positivos/inmunología , Células Dendríticas/inmunología , Malaria Falciparum/inmunología , Plasmodium falciparum/inmunología , Proteína 2 Ligando de Muerte Celular Programada 1/metabolismo , Receptor de Muerte Celular Programada 1/metabolismo , Adamantano/análogos & derivados , Adamantano/uso terapéutico , Adulto , Animales , Antimaláricos/uso terapéutico , Antígeno B7-H1/genética , Células Cultivadas , Ensayos Clínicos como Asunto , Células Dendríticas/parasitología , Femenino , Humanos , Inmunidad Celular , Activación de Linfocitos , Malaria Falciparum/tratamiento farmacológico , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Persona de Mediana Edad , Parasitemia/inmunología , Peróxidos/uso terapéutico , Proteína 2 Ligando de Muerte Celular Programada 1/genética , Receptor de Muerte Celular Programada 1/genética , Pirimidinas/uso terapéutico , Triazoles/uso terapéutico , Adulto Joven
10.
Nature ; 575(7782): 380-384, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31666695

RESUMEN

Mitochondria are essential regulators of cellular energy and metabolism, and have a crucial role in sustaining the growth and survival of cancer cells. A central function of mitochondria is the synthesis of ATP by oxidative phosphorylation, known as mitochondrial bioenergetics. Mitochondria maintain oxidative phosphorylation by creating a membrane potential gradient that is generated by the electron transport chain to drive the synthesis of ATP1. Mitochondria are essential for tumour initiation and maintaining tumour cell growth in cell culture and xenografts2,3. However, our understanding of oxidative mitochondrial metabolism in cancer is limited because most studies have been performed in vitro in cell culture models. This highlights a need for in vivo studies to better understand how oxidative metabolism supports tumour growth. Here we measure mitochondrial membrane potential in non-small-cell lung cancer in vivo using a voltage-sensitive, positron emission tomography (PET) radiotracer known as 4-[18F]fluorobenzyl-triphenylphosphonium (18F-BnTP)4. By using PET imaging of 18F-BnTP, we profile mitochondrial membrane potential in autochthonous mouse models of lung cancer, and find distinct functional mitochondrial heterogeneity within subtypes of lung tumours. The use of 18F-BnTP PET imaging enabled us to functionally profile mitochondrial membrane potential in live tumours.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/fisiopatología , Neoplasias Pulmonares/fisiopatología , Potencial de la Membrana Mitocondrial , Células A549 , Animales , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Ratones , Ratones Transgénicos , Compuestos Organofosforados , Tomografía de Emisión de Positrones
11.
Liver Transpl ; 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38869989

RESUMEN

The Stanford Integrated Psychosocial Assessment for Transplantation (SIPAT) is a standardized psychosocial assessment tool used in liver transplantation (LT) evaluation and has been primarily studied in patients with alcohol-associated liver disease. We aimed to evaluate the relationship between SIPAT score and metabolic syndrome severity and LT waitlist outcomes in a large cohort of patients with metabolic dysfunction-associated steatotic liver disease (MASLD). We performed a single-center retrospective cohort study of patients with MASLD evaluated for LT from 2014-2021. The utility of the previously defined total SIPAT cut-off (<21 [excellent/good candidates] vs ≥21 [minimally acceptable/high risk candidates]) was studied. Multivariable logistic regression analyses examined associations between continuous SIPAT score and LT waitlisting outcomes. Youden's J statistic was used to identify the optimal SIPAT cut-off for MASLD patients. A total of 480 patients evaluated for transplant with MASLD were included. Only 9.4% of patients had SIPAT score ≥21. Patients with SIPAT score ≥21 had higher hemoglobin A1c compared to patients with lower psychosocial risk (median (IQR): 7.8 (6.0-9.7) vs 6.6 (5.8, 7.9); p=0.04). There were no other differences in metabolic comorbidities between SIPAT groups. Increasing SIPAT score was associated with decreased odds of listing (OR: 0.82 per five-point increase; p=0.003) in multivariable models. A SIPAT of ≥12 was identified as the optimal cut-off in this population, resulting in an adjusted OR for listing of 0.53 vs SIPAT <12 (p=0.001). In this large cohort of MASLD patients evaluated for LT, few patients met the previously defined high SIPAT cut-off for transplant suitability. Nevertheless, increasing SIPAT score was associated with waitlist outcome. Our suggested SIPAT cut-off of ≥12 for MASLD patients warrants further external validation using data from other centers.

12.
J Vasc Surg ; 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38556041

RESUMEN

PURPOSE: The graduate medical education community implemented virtual residency interviews in response to travel restrictions during the COVID-19 pandemic, and this approach has persisted. Although many residency applicants wish to visit in-person prospective training sites, such opportunities could bias programs toward those who are able to meet this financial burden, exacerbating equity concerns. One proposed solution is to offer applicants the opportunity to visit only after a program's rank list is "locked," avoiding favoritism to applicants who visit, but allowing applicants to experience some of the camaraderie, geography, and local effects of an in-person visit. As debate about the optimal format of residency interviews continues, it is important to investigate whether in-person program visits, completed after program rank list certification, provide meaningful benefits to applicants in the residency match process. METHODS: All vascular programs entering the 2023 integrated vascular surgery residency match were invited to participate. Programs agreed to certify their National Resident Matching Program rank lists by February 1, 2023. Applicants then had the opportunity to visit the programs at which they interviewed. The particulars of the visit were determined by the individual programs. Applicants completed their standard rank list and locked on the standard date: March 1, 2023. Applicants then completed a survey regarding the impact of the visits on their rank order list decision-making. Program directors (PDs) completed a survey regarding their experiences as well. Data were collected using REDCap. RESULTS: Twenty-one of the 74 (28%) programs participated. Nineteen PDs completed the postinterview site visit survey (response rate 90%). Applicants interviewing at the participating programs (n = 112) were informed of the study, offered the opportunity to attend postinterview site visits, and received the survey. Forty-seven applicants responded (response rate 42%). Eighty-six percent of applicants stated that the visit impacted their rank list. Most important factors were esprit de corps of the program (86%), the faculty/trainees/staff (81%), and the physical setting (62%). Seventy-one percent of those participating spent ≤$800 on their visit. Eighty-one percent were satisfied with the process. Twenty-one percent of PDs would have changed their rank list if they could have based on the applicants' in-person visit. Sixty-three percent of the visit sessions cost the programs ≤$500, and 63% were satisfied with the process. CONCLUSIONS: This study is the first to document the impact of in-person site visits by applicants on a graduate medical education match process in one specialty. Our results suggest that this process provides meaningful data to applicants that helped them with their decision-making evidenced by most altering their rank lists, while avoiding some of the critical equity issues that accompany traditional in-person interviews. This may provide a model for future interview processes for residency programs.

13.
J Vasc Surg ; 79(6): 1360-1368.e3, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38219966

RESUMEN

OBJECTIVE: Fenestrated endovascular aneurysm repair (FEVAR) has become a mainstay in treating complex aortic aneurysms, though baseline patient factors predicting long-term outcomes remain poorly understood. Proteinuria is an early marker for chronic kidney disease and associated with adverse cardiovascular outcomes, but its utility in patients with aortic aneurysms is unknown. We aimed to determine whether preoperative proteinuria impacts long-term survival after FEVAR. METHODS: A single-institution, retrospective review of all elective FEVAR was performed. Preoperative proteinuria was assessed by urinalysis: negative (0-29 mg/dL), 1+ (30-100 mg/dL), 2+ (101-299 mg/dL), and 3+ (≥300 mg/dL). The cohort was stratified by patients with proteinuria (≥30 mg/dL) vs those without (<30 mg/dL). Baseline, perioperative, and long-term outcomes were compared. The primary outcome, all-cause mortality, was evaluated by Kaplan-Meier analysis and independent predictors with Cox proportional hazards modeling. RESULTS: Among 181 patients who underwent standard FEVAR from 2012 to 2022 (mean follow-up 33 months), any proteinuria was noted in 30 patients (16.6%). Patients with proteinuria were more likely to be Black (10.0% vs 1.3%) with a lower estimated glomerular filtration rate (eGFR) (52.7 ± 24.7 vs 67.7 ± 20.5 mL/min/1.73 m2), higher Society for Vascular Surgery comorbidity score (10.9 ± 4.3 vs 8.2 ± 4.7) and calcium channel blocker therapy (50.0% vs 29.1%), and larger maximal aneurysm diameter (67.2 ± 16.9 vs 59.8 ± 9.8 mm) (all P < .05). Thirty-day mortality was higher in the proteinuria group (10.0% vs 1.3%; P = .03). Overall survival at 1 and 5 years was significantly lower for those with proteinuria (71.5% vs 92.3% and 29.5% vs 68.1%; log-rank P < .001). On multivariable analysis, preoperative proteinuria was independently associated with over threefold higher hazard of mortality (hazard ratio [HR]: 3.21, 95% confidence interval [CI]: 1.66-6.20; P < .001), whereas preoperative eGFR was not predictive (HR: 0.99, 95% CI: 0.98-1.01; P = .28). Additional significant predictors included chronic obstructive pulmonary disease (HR: 2.04), older age (HR: 1.05), and larger maximal aneurysm diameter (HR: 1.03; all P < .05). CONCLUSIONS: In our 10-year experience with FEVAR, preoperative proteinuria was observed in 17% of patients and was significantly associated with worse survival. In this cohort, proteinuria was independently associated with all-cause mortality, whereas eGFR was not, suggesting that urinalysis may provide an additional simple metric for risk-stratifying patients before FEVAR.


Asunto(s)
Implantación de Prótesis Vascular , Procedimientos Endovasculares , Proteinuria , Humanos , Estudios Retrospectivos , Proteinuria/mortalidad , Proteinuria/etiología , Femenino , Masculino , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/mortalidad , Anciano , Factores de Riesgo , Implantación de Prótesis Vascular/mortalidad , Implantación de Prótesis Vascular/efectos adversos , Medición de Riesgo , Resultado del Tratamiento , Anciano de 80 o más Años , Factores de Tiempo , Aneurisma de la Aorta Abdominal/cirugía , Aneurisma de la Aorta Abdominal/mortalidad , Aneurisma de la Aorta Abdominal/complicaciones , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Persona de Mediana Edad , Complicaciones Posoperatorias/mortalidad , Reparación Endovascular de Aneurismas
14.
BJU Int ; 133(6): 656-664, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38506328

RESUMEN

OBJECTIVE: To determine the prevalence of 'spin' (i.e., reporting practices that distort the interpretation of results by positively reflecting negative findings or downplaying potential harms) strategies and level of spin in urological observational studies and whether the use of spin has changed over time. MATERIALS AND METHODS: MEDLINE and Embase were searched to identify observational studies comparing therapeutic interventions in the top five urology journals and major urological subspecialty journals, published between 2000 and 2001, 2010 and 2011, and 2020 and 2021. RESULTS: A total of 235 studies were included. Spin was identified in 81% of studies, with a median of two strategies per study. The most commonly used strategies were inadequate implication for clinical practice (30%), causal language or causal claim (29%), and use of linguistic spin (29%). Moderate to high levels of spin were found in 55% of conclusions. From 2000 to 2020, the average number of strategies used has significantly decreased each decade (H = 27.459, P < 0.001), and the median level of spin in conclusions was significantly lower in studies published in the 2020s and 2010s than in the 2000s (H = 11.649, P = 0.003). CONCLUSIONS: Our results suggest that 81% of urological observational studies comparing therapeutic interventions contained spin. Over the past two decades, the use of spin has significantly declined, but this remains an area for improvement, with 70% of included studies published in the 2020s employing spin. Medical writing should scrupulously avoid words or phrases that are not supported by data in the manuscript.


Asunto(s)
Urología , Humanos , Estudios Observacionales como Asunto
15.
Phys Chem Chem Phys ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38958416

RESUMEN

We present an investigation of the ultrafast dynamics of the polycyclic aromatic hydrocarbon fluorene initiated by an intense femtosecond near-infrared laser pulse (810 nm) and probed by a weak visible pulse (405 nm). Using a multichannel detection scheme (mass spectra, electron and ion velocity-map imaging), we provide a full disentanglement of the complex dynamics of the vibronically excited parent molecule, its excited ionic states, and fragments. We observed various channels resulting from the strong-field ionization regime. In particular, we observed the formation of the unstable tetracation of fluorene, above-threshold ionization features in the photoelectron spectra, and evidence of ubiquitous secondary fragmentation. We produced a global fit of all observed time-dependent photoelectron and photoion channels. This global fit includes four parent ions extracted from the mass spectra, 15 kinetic-energy-resolved ionic fragments extracted from ion velocity map imaging, and five photoelectron channels obtained from electron velocity map imaging. The fit allowed for the extraction of 60 lifetimes of various metastable photoinduced intermediates.

16.
J Cutan Pathol ; 51(3): 251-257, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38084825

RESUMEN

BACKGROUND: Apocrine cystadenoma is a rare, benign adenomatous cystic neoplasm, the pathogenesis of which is not fully understood. We sought to characterize the clinical, dermatoscopic, and histopathologic features of apocrine cystadenoma and its relationship to hidrocystoma. METHODS: We retrospectively analyzed cases of apocrine cystadenoma and hidrocystoma retrieved from the dermatopathology laboratory information system. RESULTS: Of the 350 cases apocrine cystic lesions, 13 cases of apocrine cystadenomas met the inclusion criteria. The age ranged from 20 to 84 years with an average of 64 years. They were long-standing (duration 3-15 years), slow-growing, large tumors usually found on the scalp. Dermatoscopy accentuated translucent light to dark blue color and prominent vessels that were present more at the periphery. All lesions were multilocular with columnar to cuboidal lining and decapitation secretion. A large portion of the lesion consisted of a simple nonproliferative epithelial lining, identical to that observed in apocrine hidrocystomas, while the proliferative adenomatous component made up a smaller portion with two patterns: (1) tubular proliferation, which either protruded into the cystic cavity or expanded outward peripherally, or (2) papillary projections, which were multiple layers thick with fibrovascular core, sometimes accompanied by tubular proliferation. Immunohistochemical stains showed strong staining for p40 and a sparse number of cells stained for Ki-67 and p53. CONCLUSIONS: The long duration of the lesion and the large areas of simple apocrine epithelial lining suggest that apocrine cystadenomas arise from long-standing apocrine hidrocystomas. However, the retrospective nature of the study from a single institution is a limitation.


Asunto(s)
Cistoadenoma , Hidrocistoma , Neoplasias de las Glándulas Sudoríparas , Humanos , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Hidrocistoma/patología , Estudios Retrospectivos , Neoplasias de las Glándulas Sudoríparas/patología , Glándulas Apocrinas/patología , Cistoadenoma/química , Cistoadenoma/patología , Proliferación Celular
17.
J Cutan Pathol ; 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38967043

RESUMEN

Diffuse large B-cell lymphoma (DLBCL) is the most common and aggressive subtype of non-Hodgkin lymphoma. The overall risk of developing DLBCL is increased in patients with other lymphomas, such as mycosis fungoides (MF). In this report, we present an 81-year-old female with early-stage MF who simultaneously progressed to tumor stage, large-cell transformed (LCT) MF and developed a primary DLBCL in a lymph node (LN). She presented with a tumor on her leg and new lymphadenopathy in her right axilla. Skin biopsy of the tumor revealed infiltration of large atypical CD3+, CD4+, and CD30+ cells, and a smaller portion of CD8+ cells in the dermis, consistent with LCT MF. Biopsy of the axillary LN revealed diffuse sheets of CD20+, BCL-2+, c-MYC+, and CD10- cells, highly suggestive of double expressor DLBCL. High-throughput sequencing revealed monoclonal T cells in the skin tumor and a monoclonal B-cell population in the LN. The above findings led to simultaneous diagnoses of LCT MF and nodal double expressor DLBCL. Our case demonstrates the importance of performing a full pathological workup in cutaneous T-cell lymphoma patients presenting with lymphadenopathy.

18.
J Phys Chem A ; 128(22): 4548-4560, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38713032

RESUMEN

We present results from a covariance ion imaging study, which employs extensive filtering, on the relationship between fragment momenta to gain deeper insight into photofragmentation dynamics. A new data analysis approach is introduced that considers the momentum partitioning between the fragments of the breakup of a molecular polycation to disentangle concurrent fragmentation channels, which yield the same ion species. We exploit this approach to examine the momentum exchange relationship between the products, which provides direct insight into the dynamics of molecular fragmentation. We apply these techniques to extensively characterize the dissociation of 1-iodopropane and 2-iodopropane dications prepared by site-selective ionization of the iodine atom using extreme ultraviolet intense femtosecond laser pulses with a photon energy of 95 eV. Our assignments are supported by classical simulations, using parameters largely obtained directly from the experimental data.

19.
J Chem Phys ; 160(24)2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38934634

RESUMEN

We present a simple approximation to estimate the largest charge that a given molecule can hold until fragmentation into smaller charged species becomes more energetically favorable. This approximation solely relies on the ionization potentials, electron affinities of the parent and fragment species, and also on the neutral parent's dissociation energy. By parameterizing these quantities, it is possible to obtain analytical phase diagrams of polycationic stability. We demonstrate the applicability of this approach by discussing the maximal charge dependence on the size of the molecular system. A numerical demonstration for linear polyenes, monocyclic annulenes, and helium clusters is provided.

20.
Am J Otolaryngol ; 45(1): 104086, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37948818

RESUMEN

PURPOSE: Our primary aim was to understand and describe the impact of COVID-19 on the incidence and etiology of facial trauma in the state of Mississippi. METHODS: Retrospective review of facial trauma-related Emergency Department encounters in Mississippi from March 11, 2019 to March 10, 2021, divided into three time periods using the state of Mississippi's Governor's Office Executive Orders. Chi-square tests and segmented linear regressions were used for analysis. RESULTS: Patients presenting with facial trauma were typically male, 18-44 years old, and lived in urban zip codes. Insurance payors significantly differed across time periods. There were no significant differences in self-inflicted assault or accidental injury between the 3 time periods, with pre- and pandemic patients more likely to be self-pay while patients during recovery being more likely to have private insurance. During the pandemic, facial trauma from a family member, partner or spouse, or other person in the household significantly increased. CONCLUSION: Similar accidental facial trauma trends may reflect lower adherence to social distancing guidelines. The increase in facial trauma perpetrated by family members is consistent with reported increases in domestic violence during the pandemic. While overall facial trauma demographic patterns did not change significantly during the COVID-19 pandemic, there were notable changes in the etiology and insurance payor of facial trauma cases. LAY SUMMARY: The COVID-19 pandemic impacted healthcare systems worldwide, and our study seeks to understand how the pandemic affected incidence of facial trauma.


Asunto(s)
COVID-19 , Traumatismos Faciales , Humanos , Masculino , Adolescente , Adulto Joven , Adulto , COVID-19/epidemiología , Mississippi/epidemiología , Centros Traumatológicos , Pandemias , Traumatismos Faciales/epidemiología , Traumatismos Faciales/etiología , Estudios Retrospectivos
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