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1.
Nat Immunol ; 23(2): 318-329, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35058616

RESUMEN

Tuberculosis (TB) in humans is characterized by formation of immune-rich granulomas in infected tissues, the architecture and composition of which are thought to affect disease outcome. However, our understanding of the spatial relationships that control human granulomas is limited. Here, we used multiplexed ion beam imaging by time of flight (MIBI-TOF) to image 37 proteins in tissues from patients with active TB. We constructed a comprehensive atlas that maps 19 cell subsets across 8 spatial microenvironments. This atlas shows an IFN-γ-depleted microenvironment enriched for TGF-ß, regulatory T cells and IDO1+ PD-L1+ myeloid cells. In a further transcriptomic meta-analysis of peripheral blood from patients with TB, immunoregulatory trends mirror those identified by granuloma imaging. Notably, PD-L1 expression is associated with progression to active TB and treatment response. These data indicate that in TB granulomas, there are local spatially coordinated immunoregulatory programs with systemic manifestations that define active TB.


Asunto(s)
Granuloma/inmunología , Tuberculosis/inmunología , Antígeno B7-H1/inmunología , Células Cultivadas , Citocinas/inmunología , Perfilación de la Expresión Génica/métodos , Humanos , Indolamina-Pirrol 2,3,-Dioxigenasa/inmunología , Pulmón/inmunología , Mycobacterium tuberculosis/inmunología , Células Mieloides/inmunología
3.
Proc Natl Acad Sci U S A ; 119(15): e2113561119, 2022 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-35394862

RESUMEN

Short-term probabilistic forecasts of the trajectory of the COVID-19 pandemic in the United States have served as a visible and important communication channel between the scientific modeling community and both the general public and decision-makers. Forecasting models provide specific, quantitative, and evaluable predictions that inform short-term decisions such as healthcare staffing needs, school closures, and allocation of medical supplies. Starting in April 2020, the US COVID-19 Forecast Hub (https://covid19forecasthub.org/) collected, disseminated, and synthesized tens of millions of specific predictions from more than 90 different academic, industry, and independent research groups. A multimodel ensemble forecast that combined predictions from dozens of groups every week provided the most consistently accurate probabilistic forecasts of incident deaths due to COVID-19 at the state and national level from April 2020 through October 2021. The performance of 27 individual models that submitted complete forecasts of COVID-19 deaths consistently throughout this year showed high variability in forecast skill across time, geospatial units, and forecast horizons. Two-thirds of the models evaluated showed better accuracy than a naïve baseline model. Forecast accuracy degraded as models made predictions further into the future, with probabilistic error at a 20-wk horizon three to five times larger than when predicting at a 1-wk horizon. This project underscores the role that collaboration and active coordination between governmental public-health agencies, academic modeling teams, and industry partners can play in developing modern modeling capabilities to support local, state, and federal response to outbreaks.


Asunto(s)
COVID-19 , COVID-19/mortalidad , Exactitud de los Datos , Predicción , Humanos , Pandemias , Probabilidad , Salud Pública/tendencias , Estados Unidos/epidemiología
4.
J Card Fail ; 30(5): 703-716, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38452999

RESUMEN

BACKGROUND: Estimation of the effects that drugs or other interventions have on patients' symptoms and functions is crucial in heart failure trials. Traditional symptoms and functions clinical outcome assessments have important limitations. Actigraphy may help to overcome these limitations due to its objective nature and the potential for continuous recording of data. However, actigraphy is not currently accepted as clinically relevant by key stakeholders. METHODS AND RESULTS: In this state-of-the-art study, the key aspects to consider when implementing actigraphy in heart failure trials are discussed. They include which actigraphy-derived measures should be considered, how to build endpoints using them, how to measure and analyze them, and how to handle the patients' and sites' logistics of integrating devices into trials. A comprehensive recommendation based on the current evidence is provided. CONCLUSION: Actigraphy is technically feasible in clinical trials involving heart failure, but successful implementation and use to demonstrate clinically important differences in physical functioning with drug or other interventions require careful consideration of many design choices.


Asunto(s)
Actigrafía , Ensayos Clínicos como Asunto , Insuficiencia Cardíaca , Dispositivos Electrónicos Vestibles , Humanos , Insuficiencia Cardíaca/terapia , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/diagnóstico , Actigrafía/instrumentación , Actigrafía/métodos , Ensayos Clínicos como Asunto/métodos , Ejercicio Físico/fisiología
5.
J Dairy Sci ; 107(1): 258-277, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37690708

RESUMEN

The legalization of industrial hemp by the 2018 Farm Bill in the United States has driven a sharp increase in its cultivation, including for cannabinoid extraction. Spent hemp biomass (SHB), produced from the extraction of cannabinoids, can potentially be used as feed for dairy cows; however, it is still illegal to do so in the United States, according to the US Food and Drug Administration Center for Veterinary Medicine, due to the presence of cannabinoids and the lack of data on the effect on animals. To assess the safety of this byproduct as feed for dairy cows, late-lactation Jersey cows (245 ± 37 d in milk; 483 ± 38 kg body weight; 10 multiparous and 8 primiparous) received a basal total mixed ration (TMR) diet plus 13% alfalfa pellet (CON) or 13% pelleted SHB for 4 wk (intervention period [IP]) followed by 4 wk of withdrawal period (WP), where all cows received only the basal TMR during WP. The dry matter intake (DMI), body weight, body condition score, milk yield, milk components, and fatty acid profile, blood parameters, N metabolism, methane emission, and activity were measured. Results indicated that feeding SHB decreased DMI mainly due to the low palatability of the SHB pellet, as the cows consumed only 7.4% of the total TMR with 13.0% SHB pellet offered in the ration. However, milk yield was not affected during the IP and was higher than CON during the WP, leading to higher milk yield/DMI. Milk components were not affected, except for a tendency in decreased fat percentage. Milk fat produced by cows fed SHB had a higher proportion of oleate and bacteria-derived fatty acids than CON. The activity of the cows was not affected, except for a shorter overall lying time in SHB versus CON cows during the IP. Blood parameters related to immune function were not affected. Compared with CON, cows fed SHB had a lower cholesterol concentration during the whole experiment and higher ß-hydroxybutyric acid during the WP, while a likely low-grade inflammation during the IP was indicated by higher ceruloplasmin and reactive oxidative metabolites. Other parameters related to liver health and inflammatory response were unaffected, except for a tendency for higher activity of alkaline phosphatase during IP and a lower activity of gamma-glutamyl transferase during WP in the SHB group versus CON. The bilirubin concentration was increased in cows fed SHB, suggesting a possible decrease in the clearance ability of the liver. Digestibility of the dry matter and protein and methane emission were not affected by feeding SHB. The urea, purine derivatives, and creatinine concentration in urine was unaffected, but cows fed SHB had higher N use efficiency and lower urine volume. Altogether, our data revealed a relatively low palatability of SHB affecting DMI with minimal biological effects, except for a likely low-grade inflammation, a higher N use efficiency, and a possible decrease in liver clearance. Overall, the data support the use of SHB as a safe feed ingredient for lactating dairy cows.


Asunto(s)
Cannabinoides , Cannabis , Enfermedades de los Bovinos , Femenino , Bovinos , Animales , Leche/metabolismo , Lactancia , Biomasa , Alimentación Animal/análisis , Digestión , Dieta/veterinaria , Ácidos Grasos/metabolismo , Peso Corporal , Cannabinoides/metabolismo , Cannabinoides/farmacología , Metano/metabolismo , Nitrógeno/metabolismo , Inflamación/veterinaria , Rumen/metabolismo , Enfermedades de los Bovinos/metabolismo
6.
J Vet Pharmacol Ther ; 47(2): 65-72, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37818972

RESUMEN

This study evaluated four different formulations of itraconazole and amiodarone. Formulation 1 was Vida's combination tablet containing both active pharmaceutical ingredients (APIs). Formulation 2 was separate, commercially available human generic capsules and tablets of itraconazole and amiodarone, respectively. Formulation 3 was separate, compounded suspensions of itraconazole and amiodarone. Formulation 4 was a compounded chewable tablet of itraconazole. Eight female dogs were dosed with 5 mg/kg of itraconazole and 15 mg/kg amiodarone (except for formulation 4, which only received 5 mg/kg itraconazole) once weekly for 4 weeks using a modified Latin Square design, ensuring that all dogs received all formulations with a 7-day washout between treatments. Animals were fasted overnight prior to each dose administration, with food returned to all animals 4 h post-dose. Blood samples (3 mL) were collected pre-treatment (0) and at appropriate time points over 72 h after each dose for a total of 14 samples per dog per treatment. There was high variability in the serum concentration data within treatment groups for itraconazole. The compounded suspensions were difficult to dose due to the nature of the formulations. The volumes dosed were accurate and consistent, but the suspension was thin and settled immediately when shaking was stopped for both itraconazole and amiodarone. All serum samples following itraconazole chewable tablet administration were not detectable or just above itraconazole's LOQ and thus did not allow for pharmacokinetic determination.


Asunto(s)
Itraconazol , Perros , Femenino , Humanos , Animales , Equivalencia Terapéutica , Comprimidos , Área Bajo la Curva , Administración Oral , Suspensiones , Estudios Cruzados
7.
J Vet Pharmacol Ther ; 47(4): 288-293, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38407510

RESUMEN

In the United States, a generic Type A medicated article product can gain the FDA approval by demonstrating bioequivalence (BE) to the pioneer product by successfully conducting a blood level, pharmacodynamic, or clinical BE study. A biowaiver can be granted based on several criteria, assuming the dissolution of the test and reference products represents the only factor influencing the relative bioavailability of both products. Monensin is practically insoluble in H2O per the USP definition. Previously published data from a comparison study of monensin dissolution profiles from the pioneer product and four generic products using biorelevant media showed that generic monensin products demonstrated different dissolution profiles to the pioneer product in these USP biorelevant rumen media. This follow-up study compared the solubility profiles in simulated intestinal fluid (cFaSSIF, pH 7.5) for the pioneer product and four generic products. The generic monensin products demonstrated different in vitro dissolution profiles to the pioneer product in biorelevant media. The differences demonstrated in solubility and dissolution profiles are of concern regarding the potential efficacy of generic monensin in cattle. There are also additional concerns for the potential development of Eimeria resistance in cattle receiving a sub-therapeutic dose of monensin from a less soluble generic product.


Asunto(s)
Medicamentos Genéricos , Monensina , Solubilidad , Monensina/farmacocinética , Monensina/química , Monensina/administración & dosificación , Medicamentos Genéricos/farmacocinética , Medicamentos Genéricos/química , Equivalencia Terapéutica , Animales
8.
Crit Rev Toxicol ; 53(8): 441-479, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37850621

RESUMEN

The mechanisms of particle-induced pathogenesis in the lung remain poorly understood. Neutrophilic inflammation and oxidative stress in the lung are hallmarks of toxicity. Some investigators have postulated that oxidative stress from particle surface reactive oxygen species (psROS) on the dust produces the toxicopathology in the lungs of dust-exposed animals. This postulate was tested concurrently with the studies to elucidate the toxicity of lunar dust (LD), which is believed to contain psROS due to high-speed micrometeoroid bombardment that fractured and pulverized lunar surface regolith. Results from studies of rats intratracheally instilled (ITI) with three LDs (prepared from an Apollo-14 lunar regolith), which differed 14-fold in levels of psROS, and two toxicity reference dusts (TiO2 and quartz) indicated that psROS had no significant contribution to the dusts' toxicity in the lung. Reported here are results of further investigations by the LD toxicity study team on the toxicological role of oxidants in alveolar neutrophils that were harvested from rats in the 5-dust ITI study and from rats that were exposed to airborne LD for 4 weeks. The oxidants per neutrophils and all neutrophils increased with dose, exposure time and dust's cytotoxicity. The results suggest that alveolar neutrophils play a critical role in particle-induced injury and toxicity in the lung of dust-exposed animals. Based on these results, we propose an adverse outcome pathway (AOP) for particle-associated lung disease that centers on the crucial role of alveolar neutrophil-derived oxidant species. A critical review of the toxicology literature on particle exposure and lung disease further supports a neutrophil-centric mechanism in the pathogenesis of lung disease and may explain previously reported animal species differences in responses to poorly soluble particles. Key findings from the toxicology literature indicate that (1) after exposures to the same dust at the same amount, rats have more alveolar neutrophils than hamsters; hamsters clear more particles from their lungs, consequently contributing to fewer neutrophils and less severe lung lesions; (2) rats exposed to nano-sized TiO2 have more neutrophils and more severe lesions in their lungs than rats exposed to the same mass-concentration of micron-sized TiO2; nano-sized dust has a greater number of particles and a larger total particle-cell contact surface area than the same mass of micron-sized dust, which triggers more alveolar epithelial cells (AECs) to synthesize and release more cytokines that recruit a greater number of neutrophils leading to more severe lesions. Thus, we postulate that, during chronic dust exposure, particle-inflicted AECs persistently release cytokines, which recruit neutrophils and activate them to produce oxidants resulting in a prolonged continuous source of endogenous oxidative stress that leads to lung toxicity. This neutrophil-driven lung pathogenesis explains why dust exposure induces more severe lesions in rats than hamsters; why, on a mass-dose basis, nano-sized dusts are more toxic than the micron-sized dusts; why lung lesions progress with time; and why dose-response curves of particle toxicity exhibit a hockey stick like shape with a threshold. The neutrophil centric AOP for particle-induced lung disease has implications for risk assessment of human exposures to dust particles and environmental particulate matter.


Asunto(s)
Polvo , Enfermedades Pulmonares , Cricetinae , Ratas , Humanos , Animales , Neutrófilos/patología , Pulmón , Citocinas/toxicidad , Oxidantes/toxicidad , Tamaño de la Partícula
9.
Int J Mol Sci ; 24(17)2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37686440

RESUMEN

Platelets play crucial roles in the development and progression of coronary artery disease (CAD). The triggering receptor expressed in myeloid cells-like transcript-1 (TLT-1) is stored in platelet α granules, and activated platelets release a soluble fragment (sTLT-1). We set out to better characterize the constituent amino acids of sTLT-1 and to evaluate sTLT-1 for use as a biomarker in patients with stable CAD. We evaluated sTLT-1 release using immunoprecipitation and mass spectrometry and employed statistical methods to retrospectively correlate sTLT-1 concentrations, utilizing ELISA in plasma samples from 1510 patients with documented stable CAD. We identified TLT-1 residues to 133 in platelet releasates. ADAM17 cuts TLT-1, suggesting that S136 is the C-terminal amino acid in sTLT-1. Our results revealed that for CAD patients, sTLT-1 levels did not differ significantly according to primary outcomes of death or major cardiac event; however, patients with left ventricular (LV) dysfunction had significantly lower plasma sTLT-1 levels as compared to those with normal LV function (981.62 ± 1141 pg/mL vs. 1247.48 ± 1589 pg/mL; p = 0.003). When patients were stratified based on sTLT-1 peak frequency distribution (544 pg/mL), a significant association with congestive heart failure was identified (OR = 2.94; 1.040-8.282; p = 0.042), which could be explained by LV dysfunction.


Asunto(s)
Enfermedad de la Arteria Coronaria , Disfunción Ventricular Izquierda , Humanos , Enfermedad de la Arteria Coronaria/genética , Estudios Retrospectivos , Células Mieloides , Plaquetas , Aminoácidos
10.
Eur Respir J ; 60(5)2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35551093

RESUMEN

BACKGROUND: Data describing cardiovascular outcomes in patients with coronavirus disease 2019 (COVID-19) and chronic kidney disease (CKD) are lacking. We compared cardiovascular outcomes of patients with and without COVID-19, stratified by CKD status. METHODS: This retrospective, multi-regional data-linkage study utilised individual patient-level data from two Scottish cohorts. All patients tested for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Cohort 1 between 1 February 2020 and 31 March 2021 and in Cohort 2 between 28 February 2020 and 8 February 2021 were included. RESULTS: Overall, 86 964 patients were tested for SARS-CoV-2. There were 36 904 patients (mean±sd age 61±21 years; 58.1% women; 15.9% CKD; 10.1% COVID-19 positive) in Cohort 1 and 50 060 patients (mean±sd age 63±20 years; 62.0% women; 16.4% CKD; 9.1% COVID-19 positive) in Cohort 2. In CKD patients, COVID-19 increased the risk of cardiovascular death by more than two-fold within 30 days (cause-specific hazard ratio (csHR) meta-estimate 2.34, 95% CI 1.83-2.99) and by 57% at the end of study follow-up (csHR meta-estimate 1.57, 95% CI 1.31-1.89). Similarly, the risk of all-cause death in COVID-19 positive versus negative CKD patients was greatest within 30 days (HR 4.53, 95% CI 3.97-5.16). Compared with patients without CKD, those with CKD had a higher risk of testing positive (11.5% versus 9.3%). Following a positive test, CKD patients had higher rates of cardiovascular death (11.1% versus 2.7%), cardiovascular complications and cardiovascular hospitalisations (7.1% versus 3.3%) than those without CKD. CONCLUSIONS: COVID-19 increases the risk of cardiovascular and all-cause death in CKD patients, especially in the short-term. CKD patients with COVID-19 are also at a disproportionate risk of cardiovascular complications than those without CKD.


Asunto(s)
COVID-19 , Insuficiencia Renal Crónica , Humanos , Femenino , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Masculino , SARS-CoV-2 , Estudios Retrospectivos , Insuficiencia Renal Crónica/complicaciones , Hospitalización , Factores de Riesgo
11.
Rheumatology (Oxford) ; 61(5): 1966-1974, 2022 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-34505902

RESUMEN

OBJECTIVES: ANCA-associated vasculitis (AAV) is a rare autoimmune disorder that commonly involves the kidney. Early identification of kidney involvement, assessing treatment-response and predicting outcome are important clinical challenges. Here, we assessed the potential utility of interval kidney biopsy in AAV. METHODS: In a tertiary referral centre with a dedicated vasculitis service, we identified patients with AAV who had undergone interval kidney biopsy, defined as a repeat kidney biopsy (following an initial biopsy showing active AAV) undertaken to determine the histological response in the kidney following induction immunosuppression. We analysed biochemical, histological and outcome data, including times to kidney failure and death for all patients. RESULTS: We identified 57 patients with AAV who underwent at least one interval kidney biopsy (59 interval biopsies in total; median time to interval biopsy ∼130 days). Of the 59 interval biopsies performed, 24 (41%) patients had clinically suspected active disease at time of biopsy which was confirmed histologically in only 42% of cases; 35 (59%) patients were in clinical disease-remission, and this was correct in 97% of cases. The clinician's impression was incorrect in one in four patients. Hematuria at interval biopsy did not correlate with histological activity. Interval biopsy showed fewer acute lesions and more chronic damage compared with initial biopsy and led to immunosuppressive treatment-change in 75% (44/59) of patients. Clinical risk prediction tools tended to operate better using interval biopsy data. CONCLUSION: Interval kidney biopsy is useful for determining treatment-response and subsequent disease management in AAV. It may provide better prognostic information than initial kidney biopsy and should be considered for inclusion into future clinical trials and treatment protocols for patients with AAV.


Asunto(s)
Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos , Fallo Renal Crónico , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/complicaciones , Anticuerpos Anticitoplasma de Neutrófilos , Biopsia/métodos , Femenino , Humanos , Inmunosupresores/uso terapéutico , Riñón/patología , Masculino , Estudios Retrospectivos
12.
J Neurooncol ; 160(1): 221-231, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36203027

RESUMEN

PURPOSE: Systemic chemotherapy including monotherapy with temozolomide (TMZ) or bevacizumab (BEV); two-drug combinations, such as irinotecan (IRI) and BEV, TMZ and BEV and a three-drug combination with TMZ, IRI and BEV (TIB) have been used in treating patients with progressive high-grade gliomas including glioblastoma (GBM). Most patients tolerated these regimens well with known side effects of hypertension, proteinuria, and reversible clinical myelosuppression (CM). However, organ- or system- specific toxicities from chemotherapy agents have never been examined by postmortem study. This is the largest cohort used to address this issue in glioma patients. METHODS: Postmortem tissues (from all major systems and organs) were prospectively collected and examined by standard institution autopsy and neuropathological procedures from 76 subjects, including gliomas (N = 68, 44/M, and 24/F) and brain metastases (N = 8, 5/M, and 3/F) between 2009 and 2019. Standard hematoxylin and eosin (H&E) were performed on all major organs including brain specimens. Electronic microscopic (EM) study was carried out on 14 selected subject's kidney samples per standard EM protocol. Medical records were reviewed with adverse events (AEs) analyzed and graded according to the Common Terminology Criteria for Adverse Events (CTCAE), version 4.03. A swimmer plot was utilized to visualize the timelines of patient history by treatment group. The binary logistic regression models were performed to explore any associations between treatment strategies and incident myelosuppression. RESULTS: Twenty-four glioma subjects were treated with TIB [median: 5.5 (range: 1-25) cycles] at tumor recurrence. Exposure to IRI significantly increased the frequency of CM (p = 0.05). No unexpected adverse events clinically, or permanent end-organ damage during postmortem examination was identified in glioma subjects who had received standard or prolonged duration of BEV, TMZ or TIB regimen-based chemotherapies except rare events of bone marrow suppression. The most common causes of death (COD) were tumor progression (63.2%, N = 43) followed by aspiration pneumonia (48.5%, N = 33) in glioma subjects. No COD was attributed to acute toxicity from TIB. The study also demonstrated that postmortem kidney specimen is unsuitable for studying renal ultrastructural pathological changes due to autolysis. CONCLUSION: There is no organ or system toxicity by postmortem examinations among glioma subjects who received BEV, TMZ or TIB regimen-based chemotherapies regardless of durations except for occasional bone marrow suppression and reversible myelosuppression clinically. IRI, but not the extended use of TMZ, significantly increased CM in recurrent glioma patients. COD most commonly resulted from glioma tumor progression with infiltration to brain stem and aspiration pneumonia.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Glioma , Neumonía por Aspiración , Humanos , Temozolomida/uso terapéutico , Glioblastoma/terapia , Bevacizumab/uso terapéutico , Irinotecán/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Recurrencia Local de Neoplasia/tratamiento farmacológico , Neoplasias Encefálicas/terapia , Glioma/tratamiento farmacológico
13.
Inorg Chem ; 61(18): 6742-6749, 2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35471920

RESUMEN

Iron nitride (Fe3N) and iron carbide (Fe3C) nanoparticles can be prepared via sol-gel synthesis. While sol-gel methods are simple, it can be difficult to control the crystalline composition, i.e., to achieve a Rietveld-pure product. In a previous in situ synchrotron study of the sol-gel synthesis of Fe3N/Fe3C, we showed that the reaction proceeds as follows: Fe3O4 → FeOx → Fe3N → Fe3C. There was considerable overlap between the different phases, but we were unable to ascertain whether this was due to the experimental setup (side-on heating of a quartz capillary which could lead to thermal gradients) or whether individual particle reactions proceed at different rates. In this paper, we use in situ wide- and small-angle X-ray scattering (wide-angle X-ray scattering (WAXS) and small-angle X-ray scattering (SAXS)) to demonstrate that the overlapping phases are indeed due to variable reaction rates. While the initial oxide nanoparticles have a small range of diameters, the size range expands considerably and very rapidly during the oxide-nitride transition. This has implications for the isolation of Rietveld-pure Fe3N, and in an extensive laboratory study, we were indeed unable to isolate phase-pure Fe3N. However, we made the surprising discovery that Rietveld-pure Fe3C nanoparticles can be produced at 500 °C with a sufficient furnace dwell time. This is considerably lower than the previous reports of the sol-gel synthesis of Fe3C nanoparticles.

14.
Am J Respir Crit Care Med ; 204(5): 583-595, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34015247

RESUMEN

Rationale: Our current understanding of tuberculosis (TB) pathophysiology is limited by a reliance on animal models, the paucity of human TB lung tissue, and traditional histopathological analysis, a destructive two-dimensional approach that provides limited spatial insight. Determining the three-dimensional (3D) structure of the necrotic granuloma, a characteristic feature of TB, will more accurately inform preventive TB strategies.Objectives: To ascertain the 3D shape of the human tuberculous granuloma and its spatial relationship with airways and vasculature within large lung tissues.Methods: We characterized the 3D microanatomical environment of human tuberculous lungs by using micro computed tomography, histopathology, and immunohistochemistry. By using 3D segmentation software, we accurately reconstructed TB granulomas, vasculature, and airways in three dimensions and confirmed our findings by using histopathology and immunohistochemistry.Measurements and Main Results: We observed marked heterogeneity in the morphology, volume, and number of TB granulomas in human lung sections. Unlike depictions of granulomas as simple spherical structures, human necrotic granulomas exhibit complex, cylindrical, branched morphologies that are connected to the airways and shaped by the bronchi. The use of 3D imaging of human TB lung sections provides unanticipated insight into the spatial organization of TB granulomas in relation to the airways and vasculature.Conclusions: Our findings highlight the likelihood that a single, structurally complex lesion could be mistakenly viewed as multiple independent lesions when evaluated in two dimensions. In addition, the lack of vascularization within obstructed bronchi establishes a paradigm for antimycobacterial drug tolerance. Lastly, our results suggest that bronchogenic spread of Mycobacterium tuberculosis reseeds the lung.


Asunto(s)
Granuloma/diagnóstico por imagen , Pulmón/diagnóstico por imagen , Pulmón/patología , Pulmón/ultraestructura , Tuberculosis Pulmonar/diagnóstico por imagen , Tuberculosis Pulmonar/microbiología , Tuberculosis Pulmonar/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Imagenología Tridimensional/métodos , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/patogenicidad , Sudáfrica , Microtomografía por Rayos X/métodos
15.
Inhal Toxicol ; 34(3-4): 51-67, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35294311

RESUMEN

Humans will set foot on the Moon again soon. The lunar dust (LD) is potentially reactive and could pose an inhalation hazard to lunar explorers. We elucidated LD toxicity and investigated the toxicological impact of particle surface reactivity (SR) using three LDs, quartz, and TiO2. We first isolated the respirable-size-fraction of an Apollo-14 regolith and ground two coarser samples to produce fine LDs with increased SR. SR measurements of these five respirable-sized dusts, determined by their in-vitro ability to generate hydroxyl radicals (•OH), showed that ground LDs > unground LD ≥ TiO2 ≥ quartz. Rats were each intratracheally instilled with 0, 1, 2.5, or 7.5 mg of a test dust. Toxicity biomarkers and histopathology were assessed up to 13 weeks after the bolus instillation. All dusts caused dose-dependent-increases in pulmonary lesions and toxicity biomarkers. The three LDs, which possessed mineral compositions/properties similar to Arizona volcanic ash, were moderately toxic. Despite a 14-fold •OH difference among these three LDs, their toxicities were indistinguishable. Quartz produced the lowest •OH amount but showed the greatest toxicity. Our results showed no correlation between the toxicity of mineral dusts and their ability to generate free radicals. We also showed that the amounts of oxidants per neutrophil increased with doses, time and the cytotoxicity of the dusts in the lung, which supports our postulation that dust-elicited neutrophilia is the major persistent source of oxidative stress. These results and the discussion of the crucial roles of the short-lived, continuously replenished neutrophils in dust-induced pathogenesis are presented.


Asunto(s)
Polvo , Enfermedades Pulmonares , Animales , Biomarcadores , Polvo/análisis , Enfermedades Pulmonares/inducido químicamente , Luna , Oxidantes/toxicidad , Cuarzo/toxicidad , Ratas , Dióxido de Silicio/toxicidad , Titanio
16.
Am J Pathol ; 190(2): 286-294, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31734231

RESUMEN

Murine models of Mycobacterium tuberculosis (Mtb) infection demonstrate progression of M1-like (proinflammatory) and M2-like (anti-inflammatory) macrophage morphology following primary granuloma formation. The Mtb cell wall cording factor, trehalose 6,6'-dimycolate (TDM), is a physiologically relevant and useful molecule for modeling early macrophage-mediated events during establishment of the tuberculosis-induced granuloma pathogenesis. Here, it is shown that TDM is a major driver of the early M1-like macrophage response as seen during initiation of the granulomas of primary pathology. Proinflammatory cytokines tumor necrosis factor-α, IL-1ß, IL-6, and IL-12p40 are produced in lung tissue after administration of TDM to mice. Furthermore, CD11b+CD45+ macrophages with a high surface expression of the M1-like markers CD38 and CD86 were found present in regions of pathology in lungs of mice at 7 days post-TDM introduction. Conversely, only low phenotypic marker expression of M2-like markers CD206 and EGR-2 were present on macrophages. These findings suggest that TDM plays a role in establishment of the M1-like shift in the microenvironment during primary tuberculosis.


Asunto(s)
Adyuvantes Inmunológicos/toxicidad , Factores Cordón/toxicidad , Granuloma/patología , Mediadores de Inflamación/metabolismo , Macrófagos/patología , Mycobacterium/metabolismo , Neumonía/patología , Animales , Femenino , Granuloma/inducido químicamente , Granuloma/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Ratones Endogámicos C57BL , Neumonía/inducido químicamente , Neumonía/metabolismo
17.
J Med Internet Res ; 23(6): e25868, 2021 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-36260374

RESUMEN

BACKGROUND: Health care professionals (HCPs) routinely have questions concerning the medications they are recommending. There are numerous resources available; however, each has its own advantages and disadvantages. OBJECTIVE: The purpose of this survey was to gain knowledge of the preferred methods and sources HCPs use to obtain information concerning medications. METHODS: A total of 511 HCPs (202 physicians, 105 pharmacists, 100 advance practice nurses, 53 registered nurses, and 51 physician assistants) were surveyed through a third-party market research firm. All participants were practicing in the United States. Individuals working for a pharmaceutical company were excluded. The survey collected demographics, frequency of searching medical information, types of questions searched, sources of medical information, and rationale for preferred and nonpreferred sources of medical information. Use of medical information resources were rated on a 5-point ordinal scale. Data were analyzed with descriptive statistics. RESULTS: Of the 511 respondents, 88.5% (452/511) searched for medical information either daily or several times per week. The most common questions involved dosing and administration, drug-drug interactions, adverse events and safety, clinical practice guidelines, and disease state information. The main rationale for using specific medical websites or apps and general online search engines frequently or very frequently was ease of use (medical websites or apps: 269/356, 75.6%; general online search engines: 248/284, 87.3%). Accuracy was the main rationale for frequent or very frequent use of medical literature search databases (163/245, 66.5%), prescribing labels or information (122/213, 57.3%), and professional literature (120/195, 61.5%). The main reason for rarely or never using specific medical websites or apps and medical literature search databases was unfamiliarity (medical websites or apps: 16/48, 33%; medical literature search databases: 35/78, 45%); for general online search engines, inaccuracy (34/54, 63%); and for prescribing labels or information and professional literature, excessive time (prescribing labels or information : 54/102, 52.9%; professional literature: 66/106, 62.3%). The pharmaceutical company was sometimes used as a resource for medical information. When the medical information department was used, the call center and the website were considered thorough and complete (call center: 14/25, 56%; website: 33/55, 60%). However, the rationale for not using the call center was the time required (199/346, 57.5%) and the website being unfamiliar (129/267, 48.3%). CONCLUSIONS: The driving forces in the selection of resources are accuracy and ease of use. There is an opportunity to increase awareness of all the appropriate resources for HCPs which may aid in their daily clinical decisions. Specifically, pharmaceutical company medical information departments can help fulfill this need by addressing two major challenges with use of the pharmaceutical company: lack of awareness of medical information services and the speed at which responses are disseminated. Overall, there is lack of understanding or appreciation of the range of pathways to obtain published information and knowledge from pharmaceutical company medical information services. Among the many challenges resource champions will face are the ability to effectively make resources and their platforms accessible, known, and useful to the scientific community.


Asunto(s)
Personal de Salud , Médicos , Humanos , Encuestas y Cuestionarios , Acceso a la Información , Preparaciones Farmacéuticas , Internet
18.
J Appl Clin Med Phys ; 22(8): 6-15, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34318570

RESUMEN

PURPOSE: Medical physics staffing models require periodic review due to the rapid evolution of technology and clinical techniques in radiation oncology. We present an update to a grid-based physics staffing algorithm for radiation oncology (originally published in 2012) that has been widely used in Canada over the last decade. MATERIALS AND METHODS: The physics staffing algorithm structure was modified to improve the clarity and consistency of input data. We collected information on clinical procedures, equipment inventory, and teaching activities from 15 radiation treatment centers in the province of Ontario from April 1, 2018, to March 31, 2019. Using these data sets, the algorithm's weighting parameters were adjusted to align the prediction of full-time equivalent (FTE) personnel with actual staffing levels in Ontario. The algorithm computes FTE estimates for medical physicists, physics assistants, engineering (electrical and mechanical), and information technology (IT) support. The performance of the algorithm was also tested in eight Canadian cancer centers outside of Ontario. RESULTS: The mean difference between the algorithm and actual staffing for the 23 Canadian cancer centers did not exceed 0.5 FTE for any staffing group. The results were slightly better in Ontario than in other provinces, as expected since the algorithm was optimized using Ontario data. There was a linear correlation between the algorithm predictions and the number of annual-treated cases for physicists, and physicists plus physics assistants. For other staff categories, the algorithm weighting parameters were not significantly altered, except for a reduction in mechanical engineering staff. Comparison with other published models suggests that the updated algorithm should be considered as a minimum recommended staffing level for the clinical support of radiation oncology programs. CONCLUSIONS: We support the use of grid-based physics staffing algorithms that account for clinical workload with flexibility to adapt to local conditions with variable academic and research demands.


Asunto(s)
Oncología por Radiación , Algoritmos , Canadá , Física Sanitaria , Humanos , Física , Recursos Humanos
19.
J Vet Pharmacol Ther ; 44(4): 619-627, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33206406

RESUMEN

In the United States, a generic Type A medicated article (premix) product can gain government approval by demonstrating in vivo bioequivalence (BE) to the pioneer product in a blood level, pharmacodynamic, or clinical BE study. A biowaiver can be granted based on several criteria including solubility or a dose adjusted method. Monensin is practically insoluble in H2 O per the USP definition. A comparison was conducted of monensin dissolution profiles from the pioneer product and four generic products using biorelevant media. Dissolution profiles were obtained in both Bovine Simulated Rumen Fluids - High Forage and High Grain diets. Data from twelve vessels (6 vessels per dissolution run × 2) were collected across 8 hrs for each lot and media. Data are reported as % dissolved, based upon the corresponding lot potency (mg/g). With demonstrated acceptable intra-lot variability, data were analyzed using f1 (difference factor) and f2 (similarity factor) procedures. The generic monensin products did not demonstrate similar in vitro dissolution profiles to the pioneer product in these USP biorelevant media. Differences in physical parameters (particle size, flow characteristics, and physical composition) were observed between the pioneer and generic products, but these differences had no apparent impact on biorelevant dissolution.


Asunto(s)
Monensina , Animales , Bovinos , Solubilidad , Equivalencia Terapéutica
20.
Rheumatology (Oxford) ; 59(5): 1076-1083, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-31794032

RESUMEN

OBJECTIVE: ANCA-associated vasculitis (AAV) is a small vessel vasculitis that commonly presents in the elderly. However, there are few long-term outcome data for these patients. Here, we assessed long-term outcomes in a single-centre cohort of elderly patients with AAV. Additionally, we tested whether a pre-morbid frailty score could aid prognosis. METHODS: Using a prospectively-compiled dataset, we investigated patients over the age of 65 who presented with AAV between 2005 and 2017 to a regional vasculitis centre. We used a Cox model to determine the factors associated with mortality. We also compared outcomes in pre-specified subgroups stratified by baseline frailty score, ANCA serotype and induction immunosuppression (with cyclophosphamide, rituximab or mycophenolate mofetil used as the main glucocorticoid-sparing agent). RESULTS: 83 patients were included in the study and were followed for a median of 1203 days. Median age was 74 years (range 65-92). Two- and five-year survival in the overall cohort were 83% (95% CI 75, 92%) and 75% (95% CI 65, 86%), respectively. The median cumulative dose of oral prednisolone was 2030 mg during the first three months. Only one patient received intravenous glucocorticoids. Age, frailty score and CRP at presentation were independently associated with mortality; all deaths occurred in patients aged over 75 at presentation. Patients treated with a cyclophosphamide-based induction regimen tended to be younger than those treated with rituximab or mycophenolate mofetil. Survival was better in the cyclophosphamide-treated group. CONCLUSION: In the contemporary era, the overall prognosis of AAV in elderly patients is good. Baseline frailty associates with disease outcomes including mortality. A low-dose glucocorticoid regimen (avoiding intravenous methylprednisolone) can be used to treat AAV effectively in elderly patients.


Asunto(s)
Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/tratamiento farmacológico , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/mortalidad , Evaluación Geriátrica , Inmunosupresores/uso terapéutico , Prednisolona/uso terapéutico , Administración Oral , Anciano , Anciano de 80 o más Años , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/diagnóstico , Bases de Datos Factuales , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Quimioterapia Combinada , Femenino , Fragilidad , Humanos , Masculino , Ácido Micofenólico/uso terapéutico , Estudios Retrospectivos , Medición de Riesgo , Índice de Severidad de la Enfermedad , Análisis de Supervivencia , Tiempo
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