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1.
Opt Express ; 31(9): 14196-14211, 2023 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-37157289

RESUMEN

Chiral properties of plasmonic metasurfaces, especially related to different absorption of left and right circularly polarized light leading to circular dichroism (CD), are a research hot topic in nanophotonics. There is often a need to understand the physical origin of CD for different chiral metasurfaces, and to get guidelines for the design of structures with optimized and robust CD. In this work, we numerically study CD at normal incidence in square arrays of elliptic nanoholes etched in thin metallic layers (Ag, Au, Al) on a glass substrate and tilted with respect to the symmetry axes. Strong CD arises in absorption spectra at the same wavelength region of extraordinary optical transmission, indicating highly resonant coupling between light and surface plasmon polaritons at the metal/glass and metal/air interfaces. We elucidate the physical origin of absorption CD by a careful comparison of optical spectra for different polarizations (linear and circular), with the aid of static and dynamic simulations of local enhancement of the electric field. Furthermore, we optimize the CD as a function of the ellipse parameters (diameters and tilt), the thickness of the metallic layer, and the lattice constant. We find that silver and gold metasurfaces are most useful for CD resonances above 600 nm, while aluminum metasurfaces are convenient for achieving strong CD resonances in the short-wavelength range of the visible regime and in the near UV. The results give a full picture of chiral optical effects at normal incidence in this simple nanohole array, and suggest interesting applications for chiral biomolecules sensing in such plasmonic geometries.

2.
Clin Sci (Lond) ; 137(14): 1013-1025, 2023 07 31.
Artículo en Inglés | MEDLINE | ID: mdl-37431800

RESUMEN

Ovarian cancer G protein-coupled receptor 1 (OGR1) (Gpr68) and G protein-coupled receptor 4 (GPR4) (Gpr4) are proton-activated G protein-coupled receptors that are stimulated upon increased extracellular acidity. These receptors have various physiological and pathophysiological roles in renal acid-base physiology, tissue inflammation, and fibrosis among others. Their function in injured renal tissue, however, remains mostly unclear. To address this, we investigated their role in crystalline nephropathy by increasing the oxalate intake of GPR4 KO and OGR1 KO mice. After 10 days of high-oxalate intake and 4 days of recovery, renal crystal content, histopathology, filtration function, and inflammation were assessed. While GPR4 deficiency did not show major alterations in disease progression, OGR1 KO mice had higher urinary calcium levels and exacerbated crystal accumulation accompanied by decreased creatinine clearance and urea excretion and a decreased presence of regulatory T (Treg) cells in kidney tissue. When lowering the severity of the kidney injury, OGR1 KO mice were more prone to develop crystalline nephropathy. In this setting, OGR1 KO mice displayed an increased activation of the immune system and a higher production of proinflammatory cytokines by T cells and macrophages. Taken together, in the acute setting of oxalate-induced nephropathy, the lack of the proton-activated G protein-coupled receptor (GPCR) GPR4 does not influence disease. OGR1 deficiency, however, increases crystal deposition leading to impaired kidney function. Thus, OGR1 may be important to limit kidney crystal deposition, which might subsequently be relevant for the pathophysiology of oxalate kidney stones or other crystallopathies.


Asunto(s)
Neoplasias Ováricas , Protones , Femenino , Animales , Ratones , Humanos , Receptores Acoplados a Proteínas G , Riñón , Inflamación , Oxalatos
3.
J Transl Med ; 20(1): 77, 2022 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-35123510

RESUMEN

BACKGROUND: Cardiovascular impairment contributes to increased mortality in preterm infants with chronic lung disease. Macitentan, an endothelin-1 receptor antagonist, has the potential to attenuate pulmonary and cardiovascular remodelling. METHODS: In a prospective randomized placebo-controlled intervention trial, Sprague-Dawley rats were exposed to 0.21 or 1.0 fraction of inspired oxygen (FiO2) for 19 postnatal days. Rats were treated via gavage with placebo or macitentan from days of life 5 to 19. Alveoli, pulmonary vessels, α-smooth muscle actin content in pulmonary arterioles, size of cardiomyocytes, right to left ventricular wall diameter ratio, and endothelin-1 plasma concentrations were assessed. RESULTS: FiO2 1.0 induced typical features of chronic lung disease with significant alveolar enlargement (p = 0.012), alveolar (p = 0.048) and pulmonary vessel rarefaction (p = 0.024), higher α-smooth muscle actin content in pulmonary arterioles (p = 0.009), higher right to left ventricular wall diameter ratio (p = 0.02), and larger cardiomyocyte cross-sectional area (p < 0.001). Macitentan treatment significantly increased pulmonary vessel count (p = 0.004) and decreased right to left ventricular wall diameter ratios (p = 0.002). Endothelin-1 plasma concentrations were higher compared to placebo (p = 0.015). Alveolar number and size, α-smooth muscle actin, and the cardiomyocyte cross-sectional area remained unchanged (all p > 0.05). CONCLUSION: The endothelin-1 receptor antagonist macitentan attenuated cardiovascular remodelling in an infant rat model for preterm chronic lung disease. This study underscores the potential of macitentan to reduce cardiovascular morbidity in preterm infants with chronic lung disease.


Asunto(s)
Hipertensión Pulmonar , Animales , Humanos , Recién Nacido , Recien Nacido Prematuro , Miocitos Cardíacos , Estudios Prospectivos , Pirimidinas , Ratas , Ratas Sprague-Dawley , Sulfonamidas
4.
FASEB J ; 35(12): e22039, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34793600

RESUMEN

OTUB1 is one of the most highly expressed deubiquitinases, counter-regulating the two most abundant ubiquitin chain types. OTUB1 expression is linked to the development and progression of lung cancer and idiopathic pulmonary fibrosis in humans. However, the physiological function of OTUB1 is unknown. Here, we show that constitutive whole-body Otub1 deletion in mice leads to perinatal lethality by asphyxiation. Analysis of (single-cell) RNA sequencing and proteome data demonstrated that OTUB1 is expressed in all lung cell types with a particularly high expression during late-stage lung development (E16.5, E18.5). At E18.5, the lungs of animals with Otub1 deletion presented with increased cell proliferation that decreased saccular air space and prevented inhalation. Flow cytometry-based analysis of E18.5 lung tissue revealed that Otub1 deletion increased proliferation of major lung parenchymal and mesenchymal/other non-hematopoietic cell types. Adult mice with conditional whole-body Otub1 deletion (wbOtub1del/del ) also displayed increased lung cell proliferation in addition to hyperventilation and failure to adapt the respiratory pattern to hypoxia. On the molecular level, Otub1 deletion enhanced mTOR signaling in embryonic and adult lung tissues. Based on these results, we propose that OTUB1 is a negative regulator of mTOR signaling with essential functions for lung cell proliferation, lung development, adult lung tissue homeostasis, and respiratory regulation.


Asunto(s)
Proliferación Celular , Cisteína Endopeptidasas/fisiología , Homeostasis , Hiperventilación/patología , Enfermedades Pulmonares/patología , Insuficiencia Respiratoria/patología , Serina-Treonina Quinasas TOR/metabolismo , Animales , Femenino , Hiperventilación/etiología , Enfermedades Pulmonares/etiología , Enfermedades Pulmonares/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Insuficiencia Respiratoria/etiología , Serina-Treonina Quinasas TOR/genética
5.
Liver Int ; 41(2): 321-332, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33091218

RESUMEN

BACKGROUND AND AIMS: The proprotein convertase subtilisin/kexin type 9 (PCSK9) plays a key role in cholesterol homeostasis, and its inhibition represents an effective therapy to lower low-density lipoprotein cholesterol (LDL-C) levels. In this study, we examined the impact of the PCSK9 rs11591147 loss-of-function (LOF) variant on liver damage in a multicenter collection of patients at risk of nonalcoholic steatohepatitis (NASH), in clinical samples and experimental models. METHODS: We considered 1874 consecutive individuals at risk of NASH as determined by histology. The SNP rs11591147, encoding for the p.R46L variant of PCSK9, was genotyped by TaqMan assays. We also evaluated 1) PCSK9 mRNA hepatic expression in human liver, and 2) the impact of a NASH-inducing diet in mice with hepatic overexpression of human PCSK9. RESULTS: Carriers of PCSK9 rs11591147 had lower circulating LDL-C levels and were protected against nonalcoholic fatty liver disease (NAFLD) (OR: 0.42; 95% CI: 0.22-0.81; P = .01), NASH (OR: 0.48; 95% CI: 0.26-0.87; P = .01) and more severe fibrosis (OR: 0.55; 95% CI: 0.32-0.94; P = .03) independently of clinical, metabolic and genetic confounding factors. PCSK9 hepatic expression was directly correlated with liver steatosis (P = .03). Finally, liver-specific overexpression of human PCSK9 in male mice drives NAFLD and fibrosis upon a dietary challenge. CONCLUSIONS: In individuals at risk of NASH, PCSK9 was induced with hepatic fat accumulation and PCSK9 rs11591147 LOF variant was protective against liver steatosis, NASH and fibrosis, suggesting that PCSK9 inhibition may be a new therapeutic strategy to treat NASH.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Proproteína Convertasa 9 , Animales , LDL-Colesterol , Humanos , Hígado , Masculino , Ratones , Enfermedad del Hígado Graso no Alcohólico/genética , Proproteína Convertasa 9/genética
6.
Nanotechnology ; 32(29)2021 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-33831854

RESUMEN

SERS tags are a class of nanoparticles with great potential in advanced imaging experiments. The preparation of SERS tags however is complex, as they suffer from the high variability of the SERS signals observed even at the slightest sign of aggregation. Here, we developed a method for the preparation of SERS tags based on the use of gold nanostars conjugated with neutravidin. The SERS tags here obtained are extremely stable in all biological buffers commonly employed and can be prepared at a relatively large scale in very mild conditions. The obtained SERS tags have been used to monitor the expression of fibroblast activation protein alpha (FAP) on the membrane of primary fibroblasts obtained from patients affected by Crohn's disease. The SERS tags allowed the unambiguous identification of FAP on the surface of cells thus suggesting the feasibility of semi-quantitative analysis of the target protein. Moreover, the use of the neutravidin-biotin system allows to apply the SERS tags for any other marker detection, for example, different cancer cell types, simply by changing the biotinylated antibody chosen in the analysis.


Asunto(s)
Endopeptidasas/genética , Proteínas de la Membrana/genética , Nanopartículas del Metal/química , Miofibroblastos/metabolismo , Octoxinol/química , Espectrometría Raman/métodos , Avidina/química , Biotina/química , Enfermedad de Crohn/genética , Enfermedad de Crohn/metabolismo , Enfermedad de Crohn/patología , Endopeptidasas/análisis , Endopeptidasas/metabolismo , Expresión Génica , Oro/química , Humanos , Íleon/metabolismo , Íleon/patología , Proteínas de la Membrana/análisis , Proteínas de la Membrana/metabolismo , Nanopartículas del Metal/ultraestructura , Miofibroblastos/patología , Polietilenglicoles/química , Cultivo Primario de Células , Coloración y Etiquetado
7.
Vet Pathol ; 58(1): 161-180, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32901581

RESUMEN

Immunodeficient mice engrafted with human immune cells represent an innovative tool to improve translatability of animal models for the study of human diseases. Immunophenotyping in these mice focuses on engraftment rates and cellular differentiation in blood and secondary lymphoid organs, and is predominantly carried out by FACS (fluorescent activated cell sorting) analysis; information on the morphological aspects of engraftment and the prevalence of histologic lesions is limited. We histologically examined 3- to 6-month-old NSG mice, naïve or engrafted with CD34+ human hemopoietic stem cells (HSC), and employed a quantitative immunohistochemical approach to identify human and murine cell compartments, comparing the results with the FACS data. NSG mice mainly exhibited incidental findings in lungs, kidneys, testes, and adrenal glands. A 6-month-old NSG mouse had a mediastinal lymphoblastic lymphoma. The lymphoid organs of NSG mice lacked typical lymphoid tissue architecture but frequently exhibited small periarteriolar leukocyte clusters in the spleen. Mice engrafted with human HSC frequently showed nephropathy, ovarian atrophy, cataract, and abnormal retinal development, lesions considered secondary to irradiation. In addition, 20% exhibited multisystemic granulomatous inflammatory infiltrates, dominated by human macrophages and T cells, leading to the observed 7% mortality and morbidity. Immunophenotypic data revealed variable repopulation of lymphoid organs with hCD45+ human cells, which did not always parallel the engraftment levels measured via FACS. The study describes the most common pathological features in young NSG mice after human HSC engraftment. As some of these lesions contribute to morbidity, morphological assessment of the engraftment at tissue level might help improve immunophenotypic evaluations of this animal model.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Células Madre Hematopoyéticas , Animales , Trasplante de Células Madre Hematopoyéticas/veterinaria , Humanos , Inmunofenotipificación/veterinaria , Ratones , Ratones Endogámicos NOD , Ratones SCID , Linfocitos T
8.
Am J Physiol Renal Physiol ; 318(3): F763-F771, 2020 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-31961715

RESUMEN

There is a need for improved animal models that better translate to human kidney disease to predict outcome of pharmacological effects in the patient. The diabetic BTBRob/ob mouse model mimics key features of early diabetic nephropathy in humans, but with chronic injury limited to glomeruli. To explore if we could induce an accelerated and more advanced disease phenotype that closer translates to human disease, we challenged BTBRob/ob mice with a high-protein diet (HPD; 30%) and followed the progression of metabolic and renal changes up to 20 wk of age. Animals on the HPD showed enhanced metabolic derangements, evidenced by further increased levels of glucose, HbA1C, cholesterol, and alanine aminotransferase. The urinary albumin-to-creatinine ratio was markedly increased with a 53-fold change compared with lean controls, whereas BTBRob/ob mice on the standard diet only presented an 8-fold change. HPD resulted in more advanced mesangial expansion already at 14 wk of age compared with BTBRob/ob mice on the standard diet and also aggravated glomerular pathology as well as interstitial fibrosis. Gene expression analysis revealed that HPD triggered expression of markers of fibrosis and inflammation in the kidney and increased oxidative stress markers in urine. This study showed that HPD significantly aggravated renal injury in BTBRob/ob mice by further advancing albuminuria, glomerular, and tubulointerstitial pathology by 20 wk of age. This mouse model offers closer translation to humans and enables exploration of new end points for pharmacological efficacy studies that also holds promise to shorten study length.


Asunto(s)
Diabetes Mellitus Tipo 2/patología , Dieta Rica en Proteínas/efectos adversos , Enfermedades Renales/patología , Animales , Glucemia , Nefropatías Diabéticas/metabolismo , Progresión de la Enfermedad , Femenino , Regulación de la Expresión Génica , Ratones , Ratones Endogámicos
9.
Int J Cancer ; 146(9): 2518-2530, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-31374124

RESUMEN

We describe the cloning and characterization of a novel fusion protein (termed L19-mIL12), consisting of murine interleukin-12 in single-chain format, sequentially fused to the L19 antibody in tandem diabody format. The fusion protein bound avidly to the cognate antigen (the alternatively spliced EDB domain of fibronectin), retained the activity of the parental cytokine and was able to selectively localize to murine tumors in vivo, as shown by quantitative biodistribution analysis. L19-mIL12 exhibited a potent antitumor activity in immunocompetent mice bearing CT26 carcinomas and WEHI-164 sarcomas, which could be boosted by combination with checkpoint blockade, leading to durable cancer eradication. L19-mIL12 also inhibited tumor growth in mice with Lewis lung carcinoma (LLC), but in this case, cancer cures could not be obtained, both in monotherapy and in combination. A microscopic analysis and a depletion experiment of tumor-infiltrating leukocytes illustrated the contribution of NK cells and CD8+ T cells for the anticancer activity observed in both tumor models. Upon L19-mIL12 treatment, the density of regulatory T cells (Tregs) was strongly increased in LLC, but not in CT26 tumors. A FACS analysis also revealed that the majority of CD8+ T cells in CT26 tumors were specific to the retroviral AH1 antigen.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Antineoplásicos Inmunológicos/farmacología , Linfocitos T CD8-positivos/inmunología , Neoplasias del Colon/inmunología , Sinergismo Farmacológico , Interleucina-12/administración & dosificación , Células Asesinas Naturales/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Apoptosis , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/patología , Carcinoma Pulmonar de Lewis/tratamiento farmacológico , Carcinoma Pulmonar de Lewis/inmunología , Carcinoma Pulmonar de Lewis/patología , Proliferación Celular , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/patología , Femenino , Fibronectinas/inmunología , Humanos , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/patología , Activación de Linfocitos , Linfocitos Infiltrantes de Tumor/efectos de los fármacos , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/patología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Sarcoma/tratamiento farmacológico , Sarcoma/inmunología , Sarcoma/patología , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
10.
Toxicol Pathol ; 48(6): 725-737, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32815462

RESUMEN

Thiourea-based molecules cause pulmonary edema when administered to rats at relatively low doses. However, rats survive normally lethal doses after prior exposure to a lower, nonlethal dose; this phenomenon is known as tolerance. The present study investigated the morphological and functional aspects of acute lung injury (ALI) induced by methylphenylthiourea (MPTU) in the Wistar rat and the pulmonary response involved in prevention of the injury. We identified pulmonary endothelial cells as the main target of acute MPTU injury; they exhibited ultrastructural alterations that can result in increased vascular permeability. In tolerant rats, the lungs showed only transient endothelial changes, at 24-hour post dosing, and mild type II pneumocyte hyperplasia on day 7 post dosing. They exhibited glutathione levels similar to the controls and increased expression of flavin-containing monooxygenase 1 (FMO1), the enzyme responsible for bioactivation of small thioureas in the laboratory rat. Incubation of rat pulmonary microsomal preparations with MPTU inhibited FMO activity, indicating that tolerance is related to irreversible inhibition of FMOs. The rat model of thiourea-induced pulmonary toxicity and tolerance represents an interesting approach to investigate certain aspects of the pathogenesis of ALI and therapeutic approaches to lung diseases, such as acute respiratory distress syndrome.


Asunto(s)
Lesión Pulmonar Aguda , Tiourea , Lesión Pulmonar Aguda/inducido químicamente , Animales , Células Endoteliales , Pulmón , Ratas , Ratas Wistar , Tiourea/toxicidad
11.
Toxicol Pathol ; 48(2): 302-316, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31847725

RESUMEN

Significant advances in immunotherapies have resulted in the increasing need of predictive preclinical models to improve immunotherapeutic drug development, treatment combination, and to prevent or minimize toxicity in clinical trials. Immunodeficient mice reconstituted with human immune system (HIS), termed humanized mice or HIS mice, permit detailed analysis of human immune biology, development, and function. Although this model constitutes a great translational model, some aspects need to be improved as the incomplete engraftment of immune cells, graft versus host disease and the lack of human cytokines and growth factors. In this review, we discuss current HIS platforms, their pathology, and recent advances in their development to improve the quality of human immune cell reconstitution. We also highlight new technologies that can be used to better understand these models and how improved characterization is needed for their application in immuno-oncology safety, efficacy, and new modalities therapy development.


Asunto(s)
Modelos Animales de Enfermedad , Sistema Inmunológico , Técnicas Inmunológicas , Oncología Médica/métodos , Alergia e Inmunología , Animales , Humanos , Factores Inmunológicos/farmacología , Ratones
12.
Nano Lett ; 19(10): 7013-7020, 2019 10 09.
Artículo en Inglés | MEDLINE | ID: mdl-31461291

RESUMEN

The optimization of nonlinear optical processes on the nanoscale is a crucial step for the integration of complex functionalities into compact photonic devices and metasurfaces. In such systems, photon upconversion can be achieved with higher efficiencies via third-order processes, such as third-harmonic generation (THG), thanks to the resonantly enhanced volume currents. Conversely, second-order processes, such as second-harmonic generation (SHG), are often inhibited by the symmetry of metal lattices and of common nanoantenna geometries. SHG and THG processes in plasmonic nanostructures are generally treated independently because they typically represent small perturbations in the light-matter interaction mechanisms. In this work, we demonstrate that this paradigm does not hold for plasmon-enhanced nonlinear optics by providing evidence of a sum-frequency generation (SFG) process seeded by SHG, which sizably contributes to the overall THG yield. We address this mechanism by unveiling a characteristic fingerprint in the polarization state of the THG emission from gold noncentrosymmetric nanoantennas, which directly reflects the asymmetric distribution of second-harmonic fields within the structure and does not depend on the model one employs to describe photon upconversion. We suggest that such cascaded processes may also appear for structures that exhibit only moderate SHG yields. The presence of this peculiar mechanism in THG from plasmonic nanoantennas at telecommunication wavelengths allows us to gain further insight into the physics of plasmon-enhanced nonlinear optical processes. This could be crucial in the realization of nanoscale elements for photon conversion and manipulation operating at room temperature.

13.
Int J Obes (Lond) ; 43(12): 2394-2406, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31270430

RESUMEN

BACKGROUND/OBJECTIVES: The incidence of obesity and metabolic syndrome (MetS) has rapidly increased worldwide. Roux-en-Y gastric bypass (RYGB) achieves long-term weight loss and improves MetS-associated comorbidities. Using a mouse model with a humanized lipoprotein metabolism, we elucidated whether improvements in lipid and glucose metabolism after RYGB surgery are body weight loss-dependent or not. SUBJECTS/METHODS: Male ApoE*3Leiden.CETP (ApoE3L.CETP) mice fed Western type diet for 6 weeks underwent RYGB or Sham surgery. Sham groups were either fed ad libitum or were body weight-matched (BWm) to the RYGB mice to discriminate surgical effects from body weight loss-associated effects. Before and after surgery, plasma was collected to assess the metabolic profile, and glucose tolerance and insulin sensitivity were tested. Twenty days after surgery, mice were sacrificed, and liver was collected to assess metabolic, histological and global gene expression changes after surgery. RESULTS: RYGB induced a marked reduction in body weight, which was also achieved by severe food restriction in BWm mice, and total fat mass compared to Sham ad libitum mice (Sham AL). Total cholesterol, non-high-density lipoprotein cholesterol (non-HDL-C) and ceramide were strongly reduced 20 days after surgery in RYGB compared to BWm mice. Glucose tolerance and insulin sensitivity improved 13 days after surgery similarly in RYGB and BWm mice. Liver histology confirmed lipid reduction in RYGB and BWm mice while the transcriptomics data indicated altered genes expression in lipid metabolism. CONCLUSIONS: RYGB surgery improves glucose metabolism and greatly ameliorates lipid metabolism in part in a body weight-dependent manner. Given that ApoE3L.CETP mice were extensively studied to describe the MetS, and given that RYGB improved ceramide after surgery, our data confirmed the usefulness of ApoE3L.CETP mice after RYGB in deciphering the metabolic improvements to treat the MetS.


Asunto(s)
Peso Corporal/fisiología , Derivación Gástrica , Metabolismo de los Lípidos/fisiología , Pérdida de Peso/fisiología , Animales , Apolipoproteínas E/genética , Glucemia/metabolismo , Modelos Animales de Enfermedad , Ingestión de Alimentos/fisiología , Hígado/química , Hígado/fisiología , Masculino , Síndrome Metabólico/fisiopatología , Ratones , Ratones Transgénicos
14.
J Transl Med ; 17(1): 91, 2019 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-30885241

RESUMEN

BACKGROUND: Hyperoxia-induced bronchopulmonary dysplasia (BPD) models are essential for better understanding and impacting on long-term pulmonary, cardiovascular, and neurological sequelae of this chronic disease. Only few experimental studies have systematically compared structural alterations with lung function measurements. METHODS: In three separate and consecutive series, Sprague-Dawley infant rats were exposed from day of life (DOL) 1 to 19 to either room air (0.21; controls) or to fractions of inspired oxygen (FiO2) of 0.6, 0.8, and 1.0. Our primary outcome parameters were histopathologic analyses of heart, lungs, and respiratory system mechanics, assessed via image analysis tools and the forced oscillation technique, respectively. RESULTS: Exposure to FiO2 of 0.8 and 1.0 resulted in significantly lower body weights and elevated coefficients of lung tissue damping (G) and elastance (H) when compared with controls. Hysteresivity (η) was lower due to a more pronounced increase of H when compared with G. A positive structure-function relation was demonstrated between H and the lung parenchymal content of α-smooth muscle actin (α-SMA) under hyperoxic conditions. Moreover, histology and morphometric analyses revealed alveolar simplification, fewer pulmonary arterioles, increased α-SMA content in pulmonary vessels, and right heart hypertrophy following hyperoxia. Also, in comparison to controls, hyperoxia resulted in significantly lower plasma levels of vascular endothelial growth factor (VEGF). Lastly, rats in hyperoxia showed hyperactive and a more explorative behaviour. CONCLUSIONS: Our in vivo infant rat model mimics clinical key features of BPD. To the best of our knowledge, this is the first BPD rat model demonstrating an association between lung structure and function. Moreover, we provide additional evidence that infant rats subjected to hyperoxia develop rarefaction of pulmonary vessels, augmented vascular α-SMA, and adaptive cardiac hypertrophy. Thus, our model provides a clinically relevant tool to further investigate diseases related to O2 toxicity and to evaluate novel pharmacological treatment strategies.


Asunto(s)
Cardiomegalia/etiología , Cardiomegalia/fisiopatología , Hiperoxia/complicaciones , Hiperoxia/fisiopatología , Pulmón/patología , Pulmón/fisiopatología , Rarefacción Microvascular/etiología , Rarefacción Microvascular/fisiopatología , Animales , Animales Recién Nacidos , Conducta Animal , Biomarcadores/metabolismo , Cardiomegalia/sangre , Endotelina-1/sangre , Femenino , Humanos , Hiperoxia/sangre , Pulmón/irrigación sanguínea , Rarefacción Microvascular/sangre , Miocardio/patología , Ratas Sprague-Dawley , Mecánica Respiratoria , Conducta Social , Análisis de Supervivencia , Factor A de Crecimiento Endotelial Vascular/sangre , Aumento de Peso
15.
Eur J Nucl Med Mol Imaging ; 46(9): 1919-1930, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31134301

RESUMEN

PURPOSE: The prostate-specific membrane antigen (PSMA) has emerged as an interesting target for radionuclide therapy of metastasized castration-resistant prostate cancer (mCRPC). The aim of this study was to investigate 161Tb (T1/2 = 6.89 days; Eß͞av = 154 keV) in combination with PSMA-617 as a potentially more effective therapeutic alternative to 177Lu-PSMA-617, due to the abundant co-emission of conversion and Auger electrons, resulting in an improved absorbed dose profile. METHODS: 161Tb was used for the radiolabeling of PSMA-617 at high specific activities up to 100 MBq/nmol. 161Tb-PSMA-617 was tested in vitro and in tumor-bearing mice to confirm equal properties, as previously determined for 177Lu-PSMA-617. The effects of 161Tb-PSMA-617 and 177Lu-PSMA-617 on cell viability (MTT assay) and survival (clonogenic assay) were compared in vitro using PSMA-positive PC-3 PIP tumor cells. 161Tb-PSMA-617 was further investigated in therapy studies using PC-3 PIP tumor-bearing mice. RESULTS: 161Tb-PSMA-617 and 177Lu-PSMA-617 displayed equal in-vitro properties and tissue distribution profiles in tumor-bearing mice. The viability and survival of PC-3 PIP tumor cells were more reduced when exposed to 161Tb-PSMA-617 as compared to the effect obtained with the same activities of 177Lu-PSMA-617 over the whole investigated concentration range. Treatment of mice with 161Tb-PSMA-617 (5.0 MBq/mouse and 10 MBq/mouse, respectively) resulted in an activity-dependent increase of the median survival (36 vs 65 days) compared to untreated control animals (19 days). Therapy studies to compare the effects of 161Tb-PSMA-617 and 177Lu-PSMA-617 indicated the anticipated superiority of 161Tb over 177Lu. CONCLUSION: 161Tb-PSMA-617 showed superior in-vitro and in-vivo results as compared to 177Lu-PSMA-617, confirming theoretical dose calculations that indicate an additive therapeutic effect of conversion and Auger electrons in the case of 161Tb. These data warrant more preclinical research for in-depth investigations of the proposed concept, and present a basis for future clinical translation of 161Tb-PSMA-617 for the treatment of mCRPC.


Asunto(s)
Dipéptidos/uso terapéutico , Compuestos Heterocíclicos con 1 Anillo/uso terapéutico , Neoplasias de la Próstata Resistentes a la Castración/radioterapia , Radioisótopos/uso terapéutico , Terbio/uso terapéutico , Animales , Proliferación Celular/efectos de la radiación , Supervivencia Celular/efectos de la radiación , Dipéptidos/farmacocinética , Compuestos Heterocíclicos con 1 Anillo/farmacocinética , Humanos , Masculino , Ratones , Células PC-3 , Antígeno Prostático Específico , Neoplasias de la Próstata Resistentes a la Castración/diagnóstico por imagen , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/patología , Tomografía Computarizada por Tomografía Computarizada de Emisión de Fotón Único , Distribución Tisular
16.
Vet Pathol ; 56(2): 248-258, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30355149

RESUMEN

Bovine abortion is a worldwide problem, but despite extensive histopathologic and molecular investigations, the cause of abortion remains unclear in about 70% of cases. Cellular debris is a commonly observed histopathologic finding in the fetal placenta and is often interpreted as necrosis. In this study, the nature of this cellular debris was characterized, and histologic changes in the normal fetal placenta during pregnancy and after delivery were assessed. In addition, the presence of the most common abortifacient pathogens in Switzerland ( Chlamydiaceae, Coxiella burnetii, Neospora caninum) was tested by polymerase chain reaction. We collected 51 placentomes and 235 cotyledons from 41 and from 50 cows, respectively. In total, cellular debris was present in 48 of 51 (94%) placentomes and in 225 of 235 (96%) cotyledons, inflammation occurred in 1 of 51 (2%) placentomes and in 46 of 235 (20%) cotyledons, vasculitis was seen in 1 of 51 (2%) placentomes and 46 of 235 (20%) cotyledons, and 18 of 51 (35%) placentomes and 181 of 235 (77%) cotyledons had mineralization. The amount of cellular debris correlated with areas of positive signals for cleaved caspase 3 and lamin A. Therefore, this finding was interpreted as an apoptotic process. In total, 10 of 50 cotyledons (20%) were positive for C. burnetii DNA, most likely representing subclinical infections. The results of our study indicate that histologic features in the fetal placenta such as cellular debris, inflammation, vasculitis, and mineralization must be considered physiological processes during pregnancy and after delivery. Therefore, their presence in placentae of aborted fetuses must be interpreted with caution and might not be necessarily linked to an infectious cause of abortion.


Asunto(s)
Placenta/anatomía & histología , Animales , Caspasa 3/metabolismo , Bovinos , Chlamydiaceae , Coxiella burnetii , Femenino , Lamina Tipo A/metabolismo , Neospora , Placenta/microbiología , Placenta/ultraestructura , Periodo Posparto , Embarazo , Reacción en Cadena en Tiempo Real de la Polimerasa
17.
Am J Physiol Gastrointest Liver Physiol ; 315(4): G602-G617, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-29975550

RESUMEN

The metabolic syndrome (MetS) is a major health issue worldwide and is associated with obesity, insulin resistance, and hypercholesterolemia. Several animal models were used to describe the MetS; however, many of them do not mimic well the MetS pathophysiology in humans. The ApoE*3Leiden.CETP mouse model overcomes part of this limitation, since they have a humanised lipoprotein metabolism and a heterogeneous response to MetS, similar to humans. The reported heterogeneity among them and their common classification refer to responder (R) and nonresponder (NR) mice; R mice show increased body weight, cholesterol, and triglycerides levels, whereas NR mice do not show this expected phenotype when fed a Western type diet. To define better the differences between R and NR mice, we focused on feeding behavior, body weight gain, glucose tolerance, and lipid parameters, and on an extensive pathological examination along with liver histology analysis. Our data confirmed that R mice resemble the pathological features of the human MetS: obesity, dysplipidemia, and glucose intolerance. NR mice do not develop the full dysmetabolic phenotype because of a severe inflammatory hepatic condition, which may heavily affect liver function. We conclude that R and NR mice are metabolically different and that NR mice have indications of severely impaired liver function. Hence, it is critical to identify and separate the respective mice to decrease data heterogeneity. Clinical chemistry and histological analysis should be used to confirm retrospectively the animals' classification. Moreover, we point out that NR mice may not be an appropriate control for studies involving ApoE*3Leiden.CETP R mice. NEW & NOTEWORTHY When compared with some other animal models, ApoE*3Leiden.CETP mice are better models to describe the metabolic syndrome. However, there is phenotypic heterogeneity between "responder" and "nonresponder" mice, the latter showing some evidence of hepatic pathology. A full phenotypic characterization and eventually postmortem analysis of the liver are warranted.


Asunto(s)
Apolipoproteínas E/genética , Variación Biológica Poblacional , Proteínas de Transferencia de Ésteres de Colesterol/genética , Modelos Animales de Enfermedad , Síndrome Metabólico/genética , Animales , Células Cultivadas , Conducta Alimentaria , Glucosa/metabolismo , Hígado/metabolismo , Masculino , Síndrome Metabólico/metabolismo , Síndrome Metabólico/fisiopatología , Ratones
18.
BMC Cancer ; 18(1): 922, 2018 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-30253737

RESUMEN

BACKGROUND: Protein kinase inhibitors (PKIs) are currently tested in clinical studies (phase I-III) as an alternative strategy against (recurrent) ovarian cancer. Besides their anti-tumour efficacy, several PKIs have also shown radiosensitizing effects when combined with external beam radiation. Based on these results we asked if the addition of PKIs offers a therapeutic opportunity to improve radioimmunotherapy (RIT) against ovarian cancer. Five PKIs (alisertib, MK1775, MK2206, saracatinib, temsirolimus) were chosen for cytotoxicity screenings based on their current clinical trials in the treatment of ovarian cancer and their influence on cell cycle regulation and DNA damage repair pathways. We combined selected PKIs with 177Lu-labelled anti-L1CAM monoclonal antibody chCE7 for our investigations. METHODS: PKIs cytotoxicity was determined via cell colony-forming assays. Biomarker of DNA double-strand breaks (DSBs, γH2A.X) was analysed by western blot and fluorescence microscopy. Flow cytometric measurements were performed to evaluate levels of apoptosis based on mono- or combination treatments. The best combination was used for in vivo combination therapy studies in nude mice with SKOV3ip and IGROV1 human ovarian cancer xenografts. Bonferroni correction was used to determine statistical significance for multiple comparisons. RESULTS: The highest cytotoxicity against both cell lines was observed for MK1775 and alisertib. Combinations including 177Lu-labelled mAb chCE7 and MK1775 decreased 177Lu-DOTA-chCE7 IC60-values 14-fold, compared to 6-fold, when the radioimmunoconjugate was combined with alisertib. The most effective PKI MK1775 was further evaluated and demonstrated synergistic effects in combination with 177Lu-DOTA-chCE7 against IGROV1 cells. Significantly higher amounts of DSBs were detected in IGROV1 cells after combination (91%) compared to either treatment alone (MK1775: 52%; radioimmunoconjugate: 72%; p < 0.0125). Early-apoptosis was significantly enhanced in IGROV1 cells correlating with induced DSBs (177Lu-DOTA-chCE7: 8%, MK1775: 28%, 177Lu-DOTA-chCE7 + MK1775: 40%, p < 0.0125). Immunohistochemistry analysis of γH2A.X expression levels after therapy in SKOV3ip xenografts revealed a high sensitivity of the tumour cells to MK1775 and a high radioresistance. A prominent effect of tumour growth inhibition of the RIT and of the combination therapy was observed in vivo in a late stage IGROV1 xenograft model. CONCLUSIONS: Our results warrant further evaluation of combination of MK1775 and radioimmunotherapy.


Asunto(s)
Antineoplásicos Inmunológicos/farmacología , Inmunoconjugados/farmacología , Lutecio , Molécula L1 de Adhesión de Célula Nerviosa/antagonistas & inhibidores , Pirazoles/farmacología , Pirimidinas/farmacología , Radioisótopos , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Roturas del ADN de Doble Cadena/efectos de los fármacos , Modelos Animales de Enfermedad , Femenino , Humanos , Ratones , Inhibidores de Proteínas Quinasas/farmacología , Pirimidinonas , Radioinmunoterapia , Ensayos Antitumor por Modelo de Xenoinjerto
19.
Chirality ; 30(7): 883-889, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29782670

RESUMEN

We study the chiroptical properties of one-dimensional photonic crystals supporting superchiral surface waves by introducing a simple formalism based on the Fresnel reflection matrix. We show that the proposed framework provides useful insights on the behavior of all the relevant chiroptical quantities, allowing for a deeper understanding of surface-enhanced chiral sensing platforms based on one-dimensional photonic crystals. Finally, we analyze and discuss the limitations of such platforms as the surface concentration of the target chiral analytes is gradually increased.

20.
Int J Cancer ; 140(7): 1680-1692, 2017 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-27943293

RESUMEN

Current osteosarcoma therapies cause severe treatment-related side effects and chemoresistance, and have low success rates. Consequently, alternative treatment options are urgently needed. Photodynamic therapy (PDT) is a minimally invasive, local therapy with proven clinical efficacy for a variety of tumor types. PDT is cytotoxic, provokes anti-vascular effects and stimulates tumor cell targeting mechanisms of the immune system and, consequently, has potential as a novel therapy for osteosarcoma patients. This study investigated the uptake and the dark- and phototoxicity and cytotoxic mechanisms of the photosensitizer (PS) 5,10,15,20-tetrakis(meta-hydroxyphenyl) chlorine (mTHPC, Foscan) and a liposomal mTHPC formulation (Foslip) in the human 143B and a mouse K7M2-derived osteosaroma cell line (K7M2L2) in vitro. Second, the tumor- and metastasis-suppressive efficacies of mTHPC formulations based PDT and associated mechanisms in intratibial, metastasizing osteosarcoma mouse models (143B/SCID and syngeneic K7M2L2/BALB/c) were studied. The uptake of Foscan and Foslip in vitro was time- and dose-dependent and resulted in mTHPC and light dose-dependent phototoxicity associated with apoptosis. In vivo, the uptake of both i.v. administered mTHPC formulations was higher in tumor than in healthy control tissue. PDT caused significant (Foscan p < 0.05, Foslip p < 0.001) tumor growth inhibition in both models. A significant (Foscan p < 0.001, Foslip p < 0.001) immune system-dependent suppression of lung metastasis was only observed in the K7M2L2/BALB/c model and was associated with a marked infiltration of T-lymphocytes at the primary tumor site. In conclusion, mTHPC-based PDT is effective in clinically relevant experimental osteosarcoma and suppresses lung metastasis in immunocompetent mice with beneficial effects of the liposomal mTHPC formulation Foslip.


Asunto(s)
Neoplasias Óseas/tratamiento farmacológico , Mesoporfirinas/uso terapéutico , Osteosarcoma/tratamiento farmacológico , Fotoquimioterapia , Animales , Apoptosis , Neoplasias Óseas/metabolismo , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Sistema Inmunológico , Liposomas/química , Ratones , Ratones Endogámicos BALB C , Ratones SCID , Microscopía Confocal , Metástasis de la Neoplasia , Trasplante de Neoplasias , Osteosarcoma/metabolismo , Fármacos Fotosensibilizantes/uso terapéutico , Tibia/patología
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