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1.
Artículo en Inglés | MEDLINE | ID: mdl-39171752

RESUMEN

The global obesity epidemic, with its associated comorbidities and increased risk of early mortality, underscores the urgent need for enhancing our understanding of the origins of this complex disease. It is increasingly clear that metabolism is programmed early in life and that metabolic programming can have life-long health consequences. As a critical metabolic organ sensitive to early-life stimuli, proper development of adipose tissue (AT) is crucial for life-long energy homeostasis. Early-life nutrients, especially fatty acids (FA), significantly influence the programming of AT and shape its function and metabolism. Of growing interest are the dynamic responses during pre- and postnatal development to proinflammatory omega-6 (n6) and anti-inflammatory omega-3 (n3) FA exposures in AT. In the US maternal diet, the ratio of 'pro-inflammatory' n6- to 'anti-inflammatory' n3-FA has grown dramatically due to the greater prevalence of n6-FA. Notably, AT macrophages (ATM) form a significant population within adipose stromal cells, playing not only an instrumental role in AT formation and maintenance, but also acting as key mediators of cell-to-cell lipid and cytokine signaling. Despite rapid advances in ATM and immunometabolism fields, research has focused on responses to obesogenic diets and during adulthood. Consequently, there is a significant gap in identifying the mechanisms contributing metabolic health, especially regarding lipid exposures during the establishment of ATM physiology. Our review highlights the current understanding of ATM diversity, their critical role in AT, and their potential role in early-life metabolic programming, as well as the broader implications for metabolism and health.

2.
Mol Pharm ; 21(2): 822-830, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38173242

RESUMEN

Titanium-45 (45Ti) is a radionuclide with excellent physical characteristics for use in positron emission tomography (PET) imaging, including a moderate half-life (3.08 h), decay by positron emission (85%), and a low mean positron energy of 0.439 MeV. However, challenges associated with titanium chemistry have led to the underdevelopment of this radionuclide for incorporation into radiopharmaceuticals. Expanding on our recent studies, which showed promising results for the complexation of 45Ti with the tris hydroxypyridinone (THPMe) chelator, the current work aimed to optimize the chemistry and imaging attributes of [45Ti]Ti-THP-PSMA as a new PET radiopharmaceutical. Methods. Radiolabeling of THP-PSMA was optimized with [45Ti]Ti-citrate at varying pHs and masses of the precursor. The stability of the radiolabeled complex was assessed in mouse serum for up to 6 h. The affinity of [45Ti]Ti-THP-PSMA for prostate-specific membrane antigen (PSMA) was assessed using LNCaP (PSMA +) and PC3 (PSMA -) cell lines. In vivo imaging and biodistribution analysis were performed in tumor-bearing xenograft mouse models to confirm the specificity of the tumor uptake. Results. > 95% of radiolabeling was achieved with a high specific activity of 5.6 MBq/nmol under mild conditions. In vitro cell binding studies showed significant binding of the radiolabeled complex with the PSMA-expressing LNCaP cell line (11.9 ± 1.5%/mg protein-bound activity) compared to that with the nonexpressing PC3 cells (1.9 ± 0.4%/mg protein-bound activity). In vivo imaging and biodistribution studies confirmed specific uptake in LNCaP tumors (1.6 ± 0.27% ID/g) compared to that in PC3 tumors (0.39 ± 0.2% ID/g). Conclusion. This study showed a simple one-step radiolabeling method for 45Ti with THP-PSMA under mild conditions (pH 8 and 37 °C). In vitro cell studies showed promise, but in vivo tumor xenograft studies indicated low tumor uptake. Overall, this study shows the need for more chelators for 45Ti for the development of a PET radiopharmaceutical for cancer imaging.


Asunto(s)
Tomografía Computarizada por Tomografía de Emisión de Positrones , Neoplasias de la Próstata , Masculino , Humanos , Animales , Ratones , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Radiofármacos , Neoplasias de la Próstata/metabolismo , Radioquímica , Distribución Tisular , Titanio , Glutamato Carboxipeptidasa II/metabolismo , Antígenos de Superficie/metabolismo , Tomografía de Emisión de Positrones , Radioisótopos , Quelantes , Línea Celular Tumoral
3.
Int J Mol Sci ; 25(12)2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38928386

RESUMEN

Adipose tissue, a central player in energy balance, exhibits significant metabolic flexibility that is often compromised in obesity and type 2 diabetes (T2D). Mitochondrial dysfunction within adipocytes leads to inefficient lipid handling and increased oxidative stress, which together promote systemic metabolic disruptions central to obesity and its complications. This review explores the pivotal role that mitochondria play in altering the metabolic functions of the primary adipocyte types, white, brown, and beige, within the context of obesity and T2D. Specifically, in white adipocytes, these dysfunctions contribute to impaired lipid processing and an increased burden of oxidative stress, worsening metabolic disturbances. Conversely, compromised mitochondrial function undermines their thermogenic capabilities, reducing the capacity for optimal energy expenditure in brown adipocytes. Beige adipocytes uniquely combine the functional properties of white and brown adipocytes, maintaining morphological similarities to white adipocytes while possessing the capability to transform into mitochondria-rich, energy-burning cells under appropriate stimuli. Each type of adipocyte displays unique metabolic characteristics, governed by the mitochondrial dynamics specific to each cell type. These distinct mitochondrial metabolic phenotypes are regulated by specialized networks comprising transcription factors, co-activators, and enzymes, which together ensure the precise control of cellular energy processes. Strong evidence has shown impaired adipocyte mitochondrial metabolism and faulty upstream regulators in a causal relationship with obesity-induced T2D. Targeted interventions aimed at improving mitochondrial function in adipocytes offer a promising therapeutic avenue for enhancing systemic macronutrient oxidation, thereby potentially mitigating obesity. Advances in understanding mitochondrial function within adipocytes underscore a pivotal shift in approach to combating obesity and associated comorbidities. Reigniting the burning of calories in adipose tissues, and other important metabolic organs such as the muscle and liver, is crucial given the extensive role of adipose tissue in energy storage and release.


Asunto(s)
Diabetes Mellitus Tipo 2 , Metabolismo Energético , Mitocondrias , Obesidad , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patología , Humanos , Obesidad/metabolismo , Obesidad/patología , Mitocondrias/metabolismo , Animales , Adipocitos/metabolismo , Tejido Adiposo/metabolismo , Estrés Oxidativo , Termogénesis
4.
Can J Urol ; 30(4): 11639-11643, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37633294

RESUMEN

Percutaneous nephrolithotomy (PCNL) is the gold-standard treatment for large and complex renal stones. Though associated with higher stone-free rates compared to other minimally invasive stone procedures, this comes at the expense of increased morbidity including postoperative pain and discomfort. We describe our enhanced recovery after surgery (ERAS) protocol for PCNL with emphasis on the use of erector spinae plane blocks to improve patient satisfaction and reduce postoperative opioid use and bother.


Asunto(s)
Recuperación Mejorada Después de la Cirugía , Cálculos Renales , Nefrolitotomía Percutánea , Bloqueo Nervioso , Humanos , Cálculos Renales/cirugía , Dolor Postoperatorio/etiología , Dolor Postoperatorio/prevención & control
5.
Proc Natl Acad Sci U S A ; 117(1): 656-667, 2020 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-31754030

RESUMEN

A major challenge facing the genetics of autism spectrum disorders (ASDs) is the large and growing number of candidate risk genes and gene variants of unknown functional significance. Here, we used Caenorhabditis elegans to systematically functionally characterize ASD-associated genes in vivo. Using our custom machine vision system, we quantified 26 phenotypes spanning morphology, locomotion, tactile sensitivity, and habituation learning in 135 strains each carrying a mutation in an ortholog of an ASD-associated gene. We identified hundreds of genotype-phenotype relationships ranging from severe developmental delays and uncoordinated movement to subtle deficits in sensory and learning behaviors. We clustered genes by similarity in phenomic profiles and used epistasis analysis to discover parallel networks centered on CHD8•chd-7 and NLGN3•nlg-1 that underlie mechanosensory hyperresponsivity and impaired habituation learning. We then leveraged our data for in vivo functional assays to gauge missense variant effect. Expression of wild-type NLG-1 in nlg-1 mutant C. elegans rescued their sensory and learning impairments. Testing the rescuing ability of conserved ASD-associated neuroligin variants revealed varied partial loss of function despite proper subcellular localization. Finally, we used CRISPR-Cas9 auxin-inducible degradation to determine that phenotypic abnormalities caused by developmental loss of NLG-1 can be reversed by adult expression. This work charts the phenotypic landscape of ASD-associated genes, offers in vivo variant functional assays, and potential therapeutic targets for ASD.


Asunto(s)
Trastorno del Espectro Autista/genética , Moléculas de Adhesión Celular Neuronal/genética , Habituación Psicofisiológica/genética , Fenómica/métodos , Animales , Animales Modificados Genéticamente , Trastorno del Espectro Autista/fisiopatología , Técnicas de Observación Conductual/métodos , Conducta Animal/fisiología , Caenorhabditis elegans , Proteínas de Unión al ADN/genética , Modelos Animales de Enfermedad , Epistasis Genética , Humanos , Inmunoglobulinas/genética , Locomoción/genética , Proteínas de la Membrana/genética , Mutación Missense , Fenotipo , Factores de Transcripción/genética
6.
Bioconjug Chem ; 32(7): 1242-1254, 2021 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-33241692

RESUMEN

Hexahistidine tags (His-tags), incorporated into recombinant proteins to facilitate purification using metal-affinity chromatography, are useful binding sites for radiolabeling with [99mTc(CO)3]+ and [188Re(CO)3]+ for molecular imaging and radionuclide therapy. Labeling efficiencies vary unpredictably, and the method is therefore not universally useful. To overcome this, we have made quantitative comparisons of radiolabeling of a bespoke Celluspots array library of 382 His-tag-containing peptide sequences with [99mTc(CO)3]+ and [188Re(CO)3]+ to identify key features that enhance labeling. A selected sequence with 10-fold enhanced labeling efficiency compared to the most effective literature-reported sequences was incorporated into an exemplar protein and compared biologically with non-optimized analogues, in vitro and in vivo. Optimal labeling with either [99mTc(CO)3]+ or [188Re(CO)3]+ required six consecutive His residues in the protein sequence, surrounded by several positively charged residues (Arg or Lys), and the presence of phosphate in the buffer. Cys or Met residues in the sequence were beneficial, to a lesser extent. Negatively charged residues were deleterious to labeling. His-tags with adjacent positively charged residues could be labeled as much as 40 times more efficiently than those with adjacent negatively charged residues. 31P NMR of [Re(CO)3(H2O)3]+ and electrophoresis of solutions of [99mTc(CO)3(H2O)3]+ suggest that phosphate bridges form between cationic residues and the cationic metal synthon during labeling. The trial optimized protein, a scFv targeted to the PSMA antigen expressed in prostate cancer, was readily labeled in >95% radiochemical yield, without the need for subsequent purification. Labeling occurred more quickly and to higher specific activity than comparable non-optimized proteins, while retaining specific binding to PSMA and prostate cancer in vivo. Thus, optimized His-tags greatly simplify radiolabeling of recombinant proteins making them potentially more widely and economically available for imaging and treating patients.


Asunto(s)
Histidina/química , Compuestos de Organotecnecio/química , Péptidos/química , Proteínas/química , Radiofármacos/química , Renio/química
7.
Curr Urol Rep ; 22(1): 5, 2021 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-33411109

RESUMEN

PURPOSE OF REVIEW: To review the efficacy and safety of mirabegron in men with overactive bladder (OAB) and benign prostatic hyperplasia (BPH). RECENT FINDINGS: Numerous studies have shown mirabegron to be efficacious and safe in treating symptoms of OAB. More recent studies evaluating the use of mirabegron in men with OAB and BPH have also shown the medication to be effective with few adverse side effects when used as monotherapy or in combination therapy. Mirabegron is an effective and safe treatment for men with OAB and BPH.


Asunto(s)
Acetanilidas/uso terapéutico , Agonistas de Receptores Adrenérgicos beta 3/uso terapéutico , Síntomas del Sistema Urinario Inferior/tratamiento farmacológico , Hiperplasia Prostática/tratamiento farmacológico , Tiazoles/uso terapéutico , Vejiga Urinaria Hiperactiva/tratamiento farmacológico , Agentes Urológicos/uso terapéutico , Anciano , Humanos , Síntomas del Sistema Urinario Inferior/etiología , Masculino , Hiperplasia Prostática/complicaciones , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento , Vejiga Urinaria Hiperactiva/complicaciones
8.
J Cosmet Laser Ther ; 21(3): 127-131, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-29883233

RESUMEN

PURPOSE: To examine the outcomes of sexual function in postmenopausal women and women with a history of breast cancer treated with endocrine therapy who were experiencing the symptoms of GSM for which they were treated with fractional microablative CO2 laser. MATERIALS AND METHODS: From July 2015 to October 2016, a retrospective chart review of women who underwent fractional microablative CO2 laser therapy (MonaLisa Touch, DEKA) for GSM was conducted. Several validated questionnaires were used to assess changes in symptoms and sexual function including the Female Sexual Function Index (FSFI), the Wong-Baker Faces Scale (WBFS), and the Female Sexual Distress Scale-Revised (FSDSR). Comparisons of mean symptom scores were described at baseline and six weeks after each treatment. RESULTS: There was a statistically significant improvement in every domain of FSFI, WBFS, and FSDS-R when comparing baseline symptom scores to after treatment three symptom scores for all patients. The secondary outcome was to evaluate the differences, if any, in outcomes of sexual function between postmenopausal women and women with a history of breast cancer treated with endocrine therapy. Both groups had statistically significant improvements in many domains studied. CONCLUSIONS: Fractional microablative CO2 laser therapy (MonaLisa Touch, DEKA) is an effective modality in treating the symptoms of GSM in postmenopausal women and women with a history of breast cancer treated with endocrine therapy.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Supervivientes de Cáncer , Enfermedades Urogenitales Femeninas/cirugía , Terapia por Láser/efectos adversos , Láseres de Gas/uso terapéutico , Posmenopausia/fisiología , Disfunciones Sexuales Fisiológicas/rehabilitación , Vagina/cirugía , Antineoplásicos Hormonales/uso terapéutico , Femenino , Proteínas del Choque Térmico HSP47/metabolismo , Humanos , Persona de Mediana Edad , Membrana Mucosa/metabolismo , Membrana Mucosa/cirugía , Estudios Retrospectivos , Encuestas y Cuestionarios , Factor de Crecimiento Transformador beta/metabolismo , Resultado del Tratamiento
9.
Bioconjug Chem ; 27(2): 319-28, 2016 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-26172432

RESUMEN

Multimodal nanoparticulate materials are described, offering magnetic, radionuclide, and fluorescent imaging capabilities to exploit the complementary advantages of magnetic resonance imaging (MRI), positron emission tomography/single-photon emission commuted tomography (PET/SPECT), and optical imaging. They comprise Fe3O4@NaYF4 core/shell nanoparticles (NPs) with different cation dopants in the shell or core, including Co0.16Fe2.84O4@NaYF4(Yb, Er) and Fe3O4@NaYF4(Yb, Tm). These NPs are stabilized by bisphosphonate polyethylene glycol conjugates (BP-PEG), and then show a high transverse relaxivity (r2) up to 326 mM(-1) s(-1) at 3T, a high affinity to [(18)F]-fluoride or radiometal-bisphosphonate conjugates (e.g., (64)Cu and (99m)Tc), and fluorescent emissions from 500 to 800 nm under excitation at 980 nm. The biodistribution of intravenously administered particles determined by PET/MR imaging suggests that negatively charged Co0.16Fe2.84O4@NaYF4(Yb, Er)-BP-PEG (10K) NPs cleared from the blood pool more slowly than positively charged NPs Fe3O4@NaYF4(Yb, Tm)-BP-PEG (2K). Preliminary results in sentinel lymph node imaging in mice indicate the advantages of multimodal imaging.


Asunto(s)
Óxido Ferrosoférrico/química , Fluoruros/química , Imagen por Resonancia Magnética/métodos , Nanopartículas/química , Imagen Óptica/métodos , Tomografía de Emisión de Positrones/métodos , Itrio/química , Animales , Difosfonatos/química , Difosfonatos/farmacocinética , Óxido Ferrosoférrico/farmacocinética , Fluoruros/farmacocinética , Masculino , Ratones Endogámicos C57BL , Ratones Desnudos , Imagen Multimodal/métodos , Polietilenglicoles/química , Polietilenglicoles/farmacocinética , Tomografía Computarizada de Emisión de Fotón Único/métodos , Itrio/farmacocinética
10.
Eur J Immunol ; 44(7): 2188-91, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24643793

RESUMEN

DC vaccines have been used to induce tumour-specific cytotoxic T cells . However, this approach to cancer immunotherapy has had limited success. To be successful, injected DCs need to migrate to the LNs where they can stimulate effector T cells . We and others have previously demonstrated by MRI that tumour antigen-pulsed-DCs labelled ex vivo with superparamagnetic iron oxide nanoparticles migrated to the draining LNs and are capable of activating antigen-specific T cells . The results from our study demonstrated that ex vivo superparamagnetic iron oxide nanoparticles-labelled and OVA-pulsed DCs prime cytotoxic CD8(+) T-cell responses to protect against a B16-OVA tumour challenge. In the clinic, a possible noninvasive surrogate marker for efficacy of DC vaccination is to image the specific migration and accumulation of T cells following DC vaccination.


Asunto(s)
Células Dendríticas/inmunología , Linfocitos T Citotóxicos/inmunología , Exametazima de Tecnecio Tc 99m , Vacunación , Animales , Ratones , Ratones Endogámicos BALB C , Tomografía Computarizada de Emisión de Fotón Único , Tomografía Computarizada por Rayos X
11.
Eur J Nucl Med Mol Imaging ; 42(2): 278-87, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25359636

RESUMEN

PURPOSE: (111)In (typically as [(111)In]oxinate3) is a gold standard radiolabel for cell tracking in humans by scintigraphy. A long half-life positron-emitting radiolabel to serve the same purpose using positron emission tomography (PET) has long been sought. We aimed to develop an (89)Zr PET tracer for cell labelling and compare it with [(111)In]oxinate3 single photon emission computed tomography (SPECT). METHODS: [(89)Zr]Oxinate4 was synthesised and its uptake and efflux were measured in vitro in three cell lines and in human leukocytes. The in vivo biodistribution of eGFP-5T33 murine myeloma cells labelled using [(89)Zr]oxinate4 or [(111)In]oxinate3 was monitored for up to 14 days. (89)Zr retention by living radiolabelled eGFP-positive cells in vivo was monitored by FACS sorting of liver, spleen and bone marrow cells followed by gamma counting. RESULTS: Zr labelling was effective in all cell types with yields comparable with (111)In labelling. Retention of (89)Zr in cells in vitro after 24 h was significantly better (range 71 to >90%) than (111)In (43-52%). eGFP-5T33 cells in vivo showed the same early biodistribution whether labelled with (111)In or (89)Zr (initial pulmonary accumulation followed by migration to liver, spleen and bone marrow), but later translocation of radioactivity to kidneys was much greater for (111)In. In liver, spleen and bone marrow at least 92% of (89)Zr remained associated with eGFP-positive cells after 7 days in vivo. CONCLUSION: [(89)Zr]Oxinate4 offers a potential solution to the emerging need for a long half-life PET tracer for cell tracking in vivo and deserves further evaluation of its effects on survival and behaviour of different cell types.


Asunto(s)
Compuestos Organometálicos/farmacocinética , Oxiquinolina/análogos & derivados , Radiofármacos/farmacocinética , Tomografía Computarizada de Emisión de Fotón Único , Circonio/farmacocinética , Animales , Línea Celular Tumoral , Humanos , Ratones , Ratones Endogámicos C57BL , Compuestos Organometálicos/efectos adversos , Oxiquinolina/efectos adversos , Oxiquinolina/farmacocinética , Radiofármacos/efectos adversos , Distribución Tisular , Circonio/efectos adversos
12.
Phys Chem Chem Phys ; 17(6): 4730-8, 2015 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-25588689

RESUMEN

Gold catalysts display high activity and good selectivity for partial oxidation of a number of alcohol species. In this work, we discuss the effects of oxygen adatoms and surface hydroxyls on the selectivity for oxidation of allylic alcohols (allyl alcohol and crotyl alcohol) on gold surfaces. Utilizing temperature programmed desorption (TPD), reactive molecular beam scattering (RMBS), and density functional theory (DFT) techniques, we provide evidence to suggest that the selectivity displayed towards partial oxidation versus combustion pathways is dependent on the type of oxidant species present on the gold surface. TPD and RMBS results suggest that surface hydroxyls promote partial oxidation of allylic alcohols to their corresponding aldehydes with very high selectivity, while oxygen adatoms promote both partial oxidation and combustion pathways. DFT calculations indicate that oxygen adatoms can react with acrolein to promote the formation of a bidentate surface intermediate, similar to structures that have been shown to decompose to generate combustion products over other transition metal surfaces. Surface hydroxyls do not readily promote such a process. Our results help explain phenomena observed in previous studies and may prove useful in the design of future catalysts for partial oxidation of alcohols.

13.
Phys Chem Chem Phys ; 17(32): 20588-96, 2015 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-26200213

RESUMEN

It has been reported that Pd-Au bimetallic catalysts display improved catalytic performance after adequate calcination. In this study, a model catalyst study was conducted to investigate the effects of annealing in oxygen on the surface structures of Pd-Au alloys by comparing the physicochemical properties of Pd/Au(111) surfaces that were annealed in ultrahigh vacuum (UHV) versus in an oxygen ambient. Auger electron spectroscopy (AES) and Basin hopping simulations reveal that the presence of oxygen can inhibit the diffusion of surface Pd atoms into the subsurface of the Au(111) sample. Reflection-absorption infrared spectroscopy using CO as a probe molecule (CO-RAIRS) and King-Wells measurements of O2 uptake suggest that surfaces annealed in an oxygen ambient possess more contiguous Pd sites than surfaces annealed under UHV conditions. The oxygen-annealed Pd/Au(111) surface exhibited a higher activity for CO oxidation in reactive molecular beam scattering (RMBS) experiments. This enhanced activity likely results from the higher oxygen uptake and relatively facile dissociation of oxygen admolecules due to stronger adsorbate-surface interactions as suggested by temperature-programmed desorption (TPD) measurements. These observations provide fundamental insights into the surface phenomena of Pd-Au alloys, which may prove beneficial in the design of future Pd-Au catalysts.

14.
J Allergy Clin Immunol ; 133(1): 233-9.e1, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23953710

RESUMEN

BACKGROUND: Hitherto, in vivo studies of human granulocyte migration have been based on indiscriminate labeling of total granulocyte populations. We hypothesized that the kinetics of isolated human neutrophil and eosinophil migration through major organs in vivo are fundamentally different, with the corollary that studying unseparated populations distorts measurement of both. METHODS: Blood neutrophils and eosinophils were isolated on 2 separate occasions from human volunteers by using Current Good Manufacturing Practice CD16 CliniMACS isolation, labeled with technetium 99m-hexamethylpropyleneamine oxime, and then reinfused intravenously. The kinetics of cellular efflux were imaged over 4 hours. RESULTS: Neutrophils and eosinophils were isolated to a mean purity of greater than 97% and greater than 95%, respectively. Activation of neutrophils measured as an increase in their CD11b mean fluorescence intensity in whole blood and after isolation and radiolabeling was 25.98 ± 7.59 and 51.82 ± 17.44, respectively, and was not significant (P = .052), but the mean fluorescence intensity of CD69 increased significantly on eosinophils. Analysis of the scintigraphic profile of lung efflux revealed exponential clearance of eosinophils, with a mean half-life of 4.16 ± 0.11 minutes. Neutrophil efflux was at a significantly slower half-life of 13.72 ± 4.14 minutes (P = .009). The migration of neutrophils and eosinophils was significantly different in the spleen at all time points (P = .014), in the liver at 15 minutes (P = .001), and in the bone marrow at 4 hours (P = .003). CONCLUSIONS: The kinetics of migration of neutrophils and eosinophils through the lung, spleen, and bone marrow of human volunteers are significantly different. Study of mixed populations might be misleading.


Asunto(s)
Médula Ósea/inmunología , Eosinófilos/inmunología , Hígado/inmunología , Neutrófilos/inmunología , Bazo/inmunología , Adulto , Movimiento Celular , Rastreo Celular/métodos , Femenino , Humanos , Separación Inmunomagnética , Masculino , Oximas , Receptores de IgG/metabolismo , Tecnecio
15.
J Am Chem Soc ; 136(31): 11070-8, 2014 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-25019609

RESUMEN

Pd-Au catalysts have shown exceptional performance for selective hydrogen production via HCOOH decomposition, a promising alternative to solve issues associated with hydrogen storage and distribution. In this study, we utilized temperature-programmed desorption (TPD) and reactive molecular beam scattering (RMBS) in an attempt to unravel the factors governing the catalytic properties of Pd-Au bimetallic surfaces for HCOOH decomposition. Our results show that Pd atoms at the Pd-Au surface are responsible for activating HCOOH molecules; however, the selectivity of the reaction is dictated by the identity of the surface metal atoms adjacent to the Pd atoms. Pd atoms that reside at Pd-Au interface sites tend to favor dehydrogenation of HCOOH, whereas Pd atoms in Pd(111)-like sites, which lack neighboring Au atoms, favor dehydration of HCOOH. These observations suggest that the reactivity and selectivity of HCOOH decomposition on Pd-Au catalysts can be tailored by controlling the arrangement of surface Pd and Au atoms. The findings in this study may prove informative for rational design of Pd-Au catalysts for associated reactions including selective HCOOH decomposition for hydrogen production and electro-oxidation of HCOOH in the direct formic acid fuel cell.

16.
J Am Chem Soc ; 136(17): 6489-98, 2014 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-24702503

RESUMEN

Partial oxidation of alcohols is a topic of great interest in the field of gold catalysis. In this work, we provide evidence that the partial oxidation of allyl alcohol to its corresponding aldehyde, acrolein, over oxygen-precovered gold surfaces occurs via multiple reaction pathways. Utilizing temperature-programmed desorption (TPD) with isotopically labeled water and oxygen species, reactive molecular beam scattering, and density functional theory (DFT) calculations, we demonstrate that the reaction mechanism for allyl alcohol oxidation is influenced by the relative proportions of atomic oxygen and hydroxyl species on the gold surface. Both atomic oxygen and hydroxyl species are shown to be active for allyl alcohol oxidation, but each displays a different pathway of oxidation, as indicated by TPD measurements and DFT calculations. The hydroxyl hydrogen of allyl alcohol is readily abstracted by either oxygen adatoms or adsorbed hydroxyl species on the gold surface to generate a surface-bound allyloxide intermediate, which then undergoes α-dehydrogenation via interaction with an oxygen adatom or surface hydroxyl species to generate acrolein. Mediation of a second allyloxide with the hydroxyl species lowers the activation barrier for the α-dehydrogenation process. A third pathway exists in which two hydroxyl species recombine to generate water and an oxygen adatom, which subsequently dehydrogenates allyloxide. This work may aid in the understanding of oxidative catalysis over gold and the effect of water therein.

17.
Immunology ; 138(3): 198-207, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23181380

RESUMEN

Sialoadhesin (Sn, also known as Siglec-1 and CD169) is a macrophage-restricted cell surface receptor that is conserved across mammals. Sn is a member of the sialic acid-binding IgG-like lectin (Siglec) family of proteins characterized by affinity to specifically sialylated ligands, and under normal conditions is expressed on subsets of macrophages in secondary lymphoid tissues, such as lymph node and spleen. However, Sn-positive macrophages can also be found in a variety of pathological conditions, including (autoimmune) inflammatory infiltrates and tumours. Sn has been shown to contribute to sialylated pathogen uptake, antigen presentation and lymphocyte proliferation, and to influence both immunity and tolerance. This review presents Sn as a macrophage-specific marker of inflammation and immunoregulation with the potential to becoming an important biomarker for immunologically active macrophages and a target for therapy.


Asunto(s)
Inflamación/inmunología , Inflamación/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Lectina 1 Similar a Ig de Unión al Ácido Siálico/metabolismo , Animales , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/metabolismo , Biomarcadores/metabolismo , Regulación de la Expresión Génica , Humanos , Inflamación/genética , Ácido N-Acetilneuramínico/metabolismo , Neoplasias/inmunología , Neoplasias/metabolismo , Lectina 1 Similar a Ig de Unión al Ácido Siálico/genética
18.
J Endourol ; 37(10): 1075-1080, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37578113

RESUMEN

Introduction and Objective: Postoperative infection and sepsis account for the most common complications following percutaneous nephrolithotomy (PCNL), as high as 14% in low-risk patients. Although the American Urological Association (AUA) recommends perioperative antibiotics for 24 hours or less for PCNL, practice patterns vary regarding duration of antibiotic therapy. We aimed to compare the efficacy of 24-hour antibiotic coverage vs short-course protocol of antibiotic prophylaxis for PCNL. Materials and Methods: Low-risk patients with a sterile preoperative urine culture undergoing PCNL were prospectively randomized to antibiotics for up to 24 hours after procedure (24Hr) or continued until external urinary catheters were removed (CR) study groups. Patients were given a first generation cephalosporin, or ciprofloxacin in patients with penicillin allergy. Exclusion criteria included age <18 years, receiving antibiotics immediately before the procedure, history of urosepsis, presence of indwelling catheter >1 week, multistage procedure, immunosuppression, pregnancy, multiple antibiotic allergies, and patients who are breastfeeding. Results: Ninety-eight patients were randomized to either 24Hr (n = 49) or CR (n = 49). Mean duration of antibiotic administration was 20.6 and 34.0 hours in the 24Hr and CR groups (p = 0.04), respectively. Age, comorbidities, stone size, operative time, number of punctures, dilations, and proportion of "tubeless" procedures were similar between groups. There were no differences in febrile episodes, rates of systemic inflammatory response syndrome, bacteremia, or culture-proven postoperative urinary tract infection between the 24Hr and CR groups. Overall complication rates were similar between groups. In a subgroup analysis which excluded "tubeless" patients (24 and 29 patients in 24Hr and CR groups, respectively), no differences were seen in postoperative outcomes. Conclusions: In a randomized, prospective study, we found that a 24-hour protocol for antibiotic prophylaxis is not associated with increased risk of infection-related events compared to giving antibiotics until external catheters are removed in patients with low infectious risk undergoing PCNL. Clinicaltrials.gov: NCT02579161.

19.
RSC Chem Biol ; 4(1): 65-73, 2023 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-36685254

RESUMEN

Cell labelling agents that enable longitudinal in vivo tracking of administered cells will support the clinical development of cell-based therapies. Radionuclide imaging with gamma and positron-emitting radioisotopes can provide quantitative and longitudinal mapping of cells in vivo. To make this widely accessible and adaptable to a range of cell types, new, versatile and simple methods for directly radiolabelling cells are required. We have developed [111In]In-DTPA-CTP, the first example of a radiolabelled peptide that binds to the extracellular membrane of cells, for tracking cell distribution in vivo using Single Photon Emission Computed Tomography (SPECT). [111In]In-DTPA-CTP consists of (i) myristoyl groups for insertion into the phospholipid bilayer, (ii) positively charged lysine residues for electrostatic association with negatively charged phospholipid groups at the cell surface and (iii) a diethylenetriamine pentaacetate derivative that coordinates the γ-emitting radiometal, [111In]In3+. [111In]In-DTPA-CTP binds to 5T33 murine myeloma cells, enabling qualitative SPECT tracking of myeloma cells' accumulation in lungs immediately after intravenous administration. This is the first report of a radiolabelled cell-membrane binding peptide for use in cell tracking.

20.
iScience ; 26(1): 105750, 2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36590177

RESUMEN

Establishing metabolic programming begins during fetal and postnatal development, and early-life lipid exposures play a critical role during neonatal adipogenesis. We define how neonatal consumption of a low omega-6 to -3 fatty acid ratio (n6/n3 FA ratio) establishes FA oxidation in adipocyte precursor cells (APCs) before they become adipocytes. In vivo, APCs isolated from mouse pups exposed to the low n6/n3 FA ratio had superior FA oxidation capacity, elevated beige adipocyte mRNAs Ppargc1α, Ucp2, and Runx1, and increased nuclear receptor NR2F2 protein. In vitro, APC treatment with NR2F2 ligand-induced beige adipocyte mRNAs and increased mitochondrial potential but not mass. Single-cell RNA-sequencing analysis revealed low n6/n3 FA ratio yielded more mitochondrial-high APCs and linked APC NR2F2 levels with beige adipocyte signatures and FA oxidation. Establishing beige adipogenesis is of clinical relevance, because fat depots with energetically active, smaller, and more numerous adipocytes improve metabolism and delay metabolic dysfunction.

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