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1.
Acta Cir Bras ; 35(1): e202000104, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32159588

RESUMEN

PURPOSE: Glutamine, as an essential part of enteral nutrition and parenteral nutrition agent, has been widely recognized to be a kind of important intestinal mucosa protectant in clinical practice and experimental research. However, the mechanisms of its protective effects are still not fully understand. Consequently, this study aimed to explore the potential mechanism of glutamine on ischemia-reperfusion (I/R) injury induced endoplasmic reticulum (ER) stress in intestine. METHODS: An experimental model of intestinal I/R in rats was established by 1 hour occlusion of the superior mesenteric artery followed by 3 hours of reperfusion. Morphologic changes of intestinal mucosa, apoptosis of epithelial cells, and expression of intestinal Grp78, Gadd153, Caspase-12, ATF4, PERK phosphorylation (P-PERK) and elF2αphosphorylation(P-elF2α) were determined. RESULTS: After I/R, the apoptotic index of intestinal mucosa epithelial cells observably increased with notable necrosis of intestinal mucosa, and the expressions of Grp78, Gadd153, Caspase-12, ATF4, P-PERK and P-elF2αall were increased. However, treatment with glutamine could significantly relieve intestinal I/R injury and apoptosis index. Moreover, glutamine could clearly up-regulate the expression of Grp78, restrain P-PERK and P-elF2α, and reduce ATF4, Gadd153 and Caspase-12 expressions. CONCLUSION: Glutamine may be involved in alleviating ER stress induced intestinal mucosa cells apoptosis.


Asunto(s)
Apoptosis/efectos de los fármacos , Estrés del Retículo Endoplásmico/efectos de los fármacos , Glutamina/farmacología , Mucosa Intestinal/efectos de los fármacos , Sustancias Protectoras/farmacología , Daño por Reperfusión/prevención & control , Factor de Transcripción Activador 4/efectos de los fármacos , Animales , Caspasa 12/efectos de los fármacos , Proteínas de Choque Térmico/efectos de los fármacos , Mucosa Intestinal/patología , Mucosa Intestinal/ultraestructura , Masculino , Arteria Mesentérica Superior/lesiones , Modelos Animales , ARN Mensajero/efectos de los fármacos , Ratas Sprague-Dawley , Factor de Transcripción CHOP/efectos de los fármacos , eIF-2 Quinasa/efectos de los fármacos
2.
Braz J Med Biol Res ; 53(3): e8761, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32159612

RESUMEN

Nitric oxide (NO) inhibition by high-dose NG-nitro-L-arginine methyl ester (L-NAME) is associated with several detrimental effects on the cardiovascular system. However, low-dose L-NAME increases NO synthesis, which in turn induces physiological cardiovascular benefits, probably by activating a protective negative feedback mechanism. Aerobic exercise, likewise, improves several cardiovascular functions in healthy hearts, but its effects are not known when chronically associated with low-dose L-NAME. Thus, we tested whether the association between low-dose L-NAME administration and chronic aerobic exercise promotes beneficial effects to the cardiovascular system, evaluating the cardiac remodeling process. Male Wistar rats were randomly assigned to control (C), L-NAME (L), chronic aerobic exercise (Ex), and chronic aerobic exercise associated to L-NAME (ExL). Aerobic training was performed with progressive intensity for 12 weeks; L-NAME (1.5 mg·kg-1·day-1) was administered by orogastric gavage. Low-dose L-NAME alone did not change systolic blood pressure (SBP), but ExL significantly increased SBP at week 8 with normalization after 12 weeks. Furthermore, ExL promoted the elevation of left ventricle (LV) end-diastolic pressure without the presence of cardiac hypertrophy and fibrosis. Time to 50% shortening and relaxation were reduced in ExL, suggesting a cardiomyocyte contractile improvement. In addition, the time to 50% Ca2+ peak was increased without alterations in Ca2+ amplitude and time to 50% Ca2+ decay. In conclusion, the association of chronic aerobic exercise and low-dose L-NAME prevented cardiac pathological remodeling and induced cardiomyocyte contractile function improvement; however, it did not alter myocyte affinity and sensitivity to intracellular Ca2+ handling.


Asunto(s)
Calcio/análisis , Inhibidores Enzimáticos/farmacología , Contracción Miocárdica/efectos de los fármacos , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico Sintasa/efectos de los fármacos , Condicionamiento Físico Animal/fisiología , Adiposidad , Animales , Peso Corporal/fisiología , Inhibidores Enzimáticos/administración & dosificación , Hemodinámica , Masculino , Modelos Animales , Actividad Motora/fisiología , Miocardio/patología , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/fisiología , NG-Nitroarginina Metil Éster/administración & dosificación , Óxido Nítrico Sintasa/metabolismo , Ratas Wistar , Presión Ventricular/efectos de los fármacos
3.
Phys Rev Lett ; 124(9): 098102, 2020 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-32202882

RESUMEN

Wavelike patterns driving transport are ubiquitous in life. Peristaltic pumps are a paradigm of efficient mass transport by contraction driven flows-often limited by energetic constraints. We show that a cost-efficient increase in pumping performance can be achieved by modulating the phase difference between harmonics to increase occlusion. In experiments we find a phase difference shift in the living peristalsis model P. polycephalum as dynamic response to forced mass transport. Our findings provide a novel metric for wavelike patterns and demonstrate the crucial role of nonlinearities in life.


Asunto(s)
Modelos Biológicos , Peristaltismo/fisiología , Physarum polycephalum/fisiología , Animales , Relojes Biológicos , Modelos Animales
5.
Zoolog Sci ; 37(1): 61-69, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32068375

RESUMEN

Iron is an essential element for hemoglobin synthesis during erythropoiesis. Iron overload, in contrast, adversely affects erythropoiesis and causes organ dysfunction. Research using various animal models may help to elucidate pathophysiological mechanisms induced by excess iron. In the present study, we evaluated the relationship between iron metabolism and erythropoietic activity in the African clawed frog, Xenopus laevis. In X. laevis, both erythropoiesis and iron metabolism occur in the liver. First, we developed a method to quantify iron levels in the liver and plasma using 2-nitroso-5-[N-n-propyl-N-(3-sulfopropyl) amino] phenol (Nitroso-PSAP). We then measured iron levels and analyzed hematopoietic parameters in frogs that were orally administered sodium ferrous citrate (SFC). The hepatic iron level increased in the SFC group, but the number of erythrocytes, hematocrit, and hemoglobin concentration did not change, suggesting that the regulation of the production and release of mature erythrocytes in the liver was not directly affected by dietary iron. At four days after administration of 2 mg/kg SFC, the number of immature erythrocytes decreased in the liver. Interestingly, atypical blood cells with hyper-segmented nuclei were observed, identified by acridine orange cell staining; these atypical blood cells were hardly detectable under the steady state. Compared with previously reported results in mice, the increase in the hepatic iron levels was small, but our results indicate that SFC affects hematopoietic activity. These results establish a novel model for iron metabolism and provide new insights into the relationship between iron metabolism and erythropoiesis in vertebrates.


Asunto(s)
Eritropoyesis/fisiología , Sobrecarga de Hierro/fisiopatología , Hígado/fisiopatología , Xenopus laevis/fisiología , Animales , Eritropoyesis/efectos de los fármacos , Compuestos Ferrosos/farmacología , Hierro/análisis , Hierro/sangre , Hierro/metabolismo , Hígado/citología , Hígado/metabolismo , Masculino , Modelos Animales , Xenopus laevis/metabolismo
6.
Nature ; 579(7798): 291-296, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32103174

RESUMEN

The DNA-dependent protein kinase (DNA-PK), which comprises the KU heterodimer and a catalytic subunit (DNA-PKcs), is a classical non-homologous end-joining (cNHEJ) factor1. KU binds to DNA ends, initiates cNHEJ, and recruits and activates DNA-PKcs. KU also binds to RNA, but the relevance of this interaction in mammals is unclear. Here we use mouse models to show that DNA-PK has an unexpected role in the biogenesis of ribosomal RNA (rRNA) and in haematopoiesis. The expression of kinase-dead DNA-PKcs abrogates cNHEJ2. However, most mice that both expressed kinase-dead DNA-PKcs and lacked the tumour suppressor TP53 developed myeloid disease, whereas all other previously characterized mice deficient in both cNHEJ and TP53 expression succumbed to pro-B cell lymphoma3. DNA-PK autophosphorylates DNA-PKcs, which is its best characterized substrate. Blocking the phosphorylation of DNA-PKcs at the T2609 cluster, but not the S2056 cluster, led to KU-dependent defects in 18S rRNA processing, compromised global protein synthesis in haematopoietic cells and caused bone marrow failure in mice. KU drives the assembly of DNA-PKcs on a wide range of cellular RNAs, including the U3 small nucleolar RNA, which is essential for processing of 18S rRNA4. U3 activates purified DNA-PK and triggers phosphorylation of DNA-PKcs at T2609. DNA-PK, but not other cNHEJ factors, resides in nucleoli in an rRNA-dependent manner and is co-purified with the small subunit processome. Together our data show that DNA-PK has RNA-dependent, cNHEJ-independent functions during ribosome biogenesis that require the kinase activity of DNA-PKcs and its phosphorylation at the T2609 cluster.


Asunto(s)
Proteínas de Unión al Calcio/metabolismo , Hematopoyesis/genética , Autoantígeno Ku/metabolismo , Linfoma/enzimología , Linfoma/fisiopatología , ARN Ribosómico 18S/metabolismo , Proteínas de Unión al Calcio/genética , Dominio Catalítico/fisiología , Reparación del ADN/genética , Activación Enzimática/genética , Células HeLa , Humanos , Linfoma/genética , Modelos Animales , Mutación , Fosforilación , Unión Proteica , Biosíntesis de Proteínas/genética , ARN Ribosómico 18S/genética , ARN Nucleolar Pequeño/metabolismo
7.
Int J Artif Organs ; 43(1): 3-9, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31900096

RESUMEN

Ex vivo testing is a fundamental step in the development of new medical devices; indeed without it, it is impossible to proceed with in vivo tests. At the University of Florence, a robotic tool for microwave thermal ablation is under development. Up to now, the thermoablation tests for the validation of the tool were carried out on non-perfused ex vivo livers, providing results that inevitably differ from those obtainable with an in vivo liver. The aim is to design, and consequently create, a compact and transportable system which allows to perfuse a swine liver with physiological solution and heparin. This device should also allow the organ to be transported from the explantation place to the laboratory, keeping it under normothermal condition. The perfusor was designed to simulate the physiological flow within the liver in the most realistic way possible. The design, construction, and optimization of the perfusor have been addressed using the physiological values of hepatic flow and pressure identified in the literature, neglecting in the first instance any load losses. Therefore, open circuit tests were conducted, validated through perfusion tests on freshly explanted pig liver; during these tests, the surface temperature of the organ was recorded using an infrared camera, and the fluid temperature was verified using an immersion probe. The perfusion test showed a good alignment with the open circuit tests, demonstrating the validity of the simplifications adopted to treat the complex vascular structure of the liver.


Asunto(s)
Hígado/fisiología , Preservación de Órganos/instrumentación , Perfusión/instrumentación , Animales , Diseño de Equipo , Trasplante de Hígado , Modelos Animales , Preservación de Órganos/métodos , Porcinos , Temperatura Ambiental
8.
Arch Oral Biol ; 111: 104665, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31951846

RESUMEN

OBJECTIVE: The objective was to systematically-review the effect of statin drugs on orthodontic-tooth-movement (OTM). DESIGN: The focused-question was "Does statin therapy affect OTM?" PubMed, Ovid Medline, Cochrane Library, Scopus, EMBASE and Web of Science databases were searched without time and language restrictions using different key words. Studies assessing the effect of adjunctive statin administration on OTM compared with orthodontic treatment alone were included. The search was performed up to and including December 2018. Data regarding the study design/grouping, subjects, age/gender, duration of follow-up, outcome variables and parameters related to OTM and statins administration were evaluated. RESULTS: Nine studies (1 clinical and 8 studies performed in animal-models) were included. Six studies used Simvastatin, whereas three studies used Atorvastatin. Six experimental studies and one clinical study reported reduction in OTM upon statin administration. Two experimental studies reported no effect of statin administration on OTM. In 90 % of the studies, the risk-of-bias was high. CONCLUSION: Based upon the high risk-of-bias and methodological inconsistencies among the included studies, the influence of statin delivery on OTM remains debatable.


Asunto(s)
Diente , Animales , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Modelos Animales , Simvastatina , Técnicas de Movimiento Dental
9.
Plast Reconstr Surg ; 145(2): 409-418, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31985633

RESUMEN

BACKGROUND: Irradiated allogeneic costal cartilage is an alternative option of cartilage graft in patients with insufficient autologous cartilage. However, complications can occur during long-term follow-up. This study investigated whether Tutoplast-processed cartilage, one of the irradiated allogeneic costal cartilages, acts as a scaffold for adipose-derived stem cells and chondrogenesis. METHODS: In vitro setting, human adipose-derived stem cells seeded onto Tutoplast-processed cartilage were cultured in chondrogenic medium and observed using a scanning electron microscope. Next, 3 types of irradiated cartilage-including Tutoplast-processed cartilage, undifferentiated stem cells on Tutoplast-processed cartilage (undifferentiated group), and chondrogenic differentiated stem cells on Tutoplast-processed cartilage (chondrogenic group)-were implanted subcutaneously into nude mice. Gross, histologic, and gene expression analyses of Tutoplast-processed cartilages were performed at postoperative weeks 2 and 4. RESULTS: Human adipose-derived stem cells subjected to in vitro three-dimensional culture differentiated into chondrocytes and expressed cartilage-specificgenes. Adipose-derived stem cells seeded onto Tutoplast-processed cartilage were differentiated into chondrocytes in chondrogenic medium. In the chondrogenic group, the chondrogenic-differentiated cells attached to the surface of the Tutoplast-processed cartilage were maintained during the follow-up and were distinct from the existing Tutoplast-processed cartilage. Moreover, the chondrogenic group had higher expression of cartilage-specific genes compared with the undifferentiated group. CONCLUSIONS: Adipose-derived stem cells seeded onto Tutoplast-processed cartilage underwent chondrogenic differentiation, generating new cartilage, which was maintained after implantation without critical complications. The findings are clinically valuable in terms of overcoming the limitations of irradiated allogeneic costal cartilage, and broaden the surgical options for treatments requiring cartilage.


Asunto(s)
Cartílago/fisiología , Condrogénesis/fisiología , Células Madre Mesenquimatosas/fisiología , Agrecanos/metabolismo , Animales , Biomarcadores/metabolismo , Cartílago/efectos de la radiación , Diferenciación Celular/fisiología , Células Cultivadas , Colágeno Tipo X/metabolismo , Femenino , Humanos , Técnicas In Vitro , Inyecciones Subcutáneas , Músculos Intercostales , Trasplante de Células Madre Mesenquimatosas/métodos , Ratones Desnudos , Microscopía Electrónica de Rastreo , Persona de Mediana Edad , Modelos Animales , Reacción en Cadena en Tiempo Real de la Polimerasa , Trasplante Heterólogo , Trasplante Homólogo
10.
Genes Dev ; 34(3-4): 239-249, 2020 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31919193

RESUMEN

Addressing the complexity of organogenesis at a system-wide level requires a complete understanding of adult cell types, their origin, and precursor relationships. The Drosophila ovary has been a model to study how coordinated stem cell units, germline, and somatic follicle stem cells maintain and renew an organ. However, lack of cell type-specific tools have limited our ability to study the origin of individual cell types and stem cell units. Here, we used a single-cell RNA sequencing approach to uncover all known cell types of the developing ovary, reveal transcriptional signatures, and identify cell type-specific markers for lineage tracing. Our study identifies a novel cell type corresponding to the elusive follicle stem cell precursors and predicts subtypes of known cell types. Altogether, we reveal a previously unanticipated complexity of the developing ovary and provide a comprehensive resource for the systematic analysis of ovary morphogenesis.


Asunto(s)
Drosophila/citología , Folículo Ovárico/citología , Células Madre/citología , Animales , Drosophila/genética , Drosophila/metabolismo , Femenino , Modelos Animales , Ovario/citología , Análisis de Secuencia de ARN , Análisis de la Célula Individual , Transcripción Genética
11.
Braz J Med Biol Res ; 53(1): e9144, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31939600

RESUMEN

Wound scarring remains a major challenge for plastic surgeons. Transforming growth factor (TGF)-ß plays a key role in the process of scar formation. Previous studies have demonstrated that truncated TGF-ß type II receptor (t-TGF-ßRII) is unable to continue signal transduction but is still capable of binding to TGF-ß, thereby blocking the TGF-ß signaling pathway. Hepatocyte growth factor (HGF) is a multifunctional growth factor that promotes tissue regeneration and wound healing. Theoretically, the combination of HGF and t-TGF-ßRII would be expected to exert a synergistic effect on promoting wound healing and reducing collagen formation. In the present study, lentivirus-mediated transfection of the two genes (t-TGF-ßRII/HGF) into fibroblasts in vitro and in a rat model in vivo was used. The results demonstrated that the expression of t-TGF-ßRII and HGF in NIH-3T3 cells was successfully induced. The expression of both molecules significantly reduced collagen I and III expression, and also inhibited fibroblast proliferation. Furthermore, histological examination and scar quantification revealed less scarring in the experimental wound in a rat model. Moreover, on macroscopic inspection, the experimental wound exhibited less visible scarring compared with the control. Therefore, the present study demonstrated that the combination gene therapy of t-TGF-ßRII and HGF promoted wound healing, with less scarring and more epithelial tissue formation, not only by suppressing the overgrowth of collagen due to its antifibrotic effect, but also by promoting tissue regeneration.


Asunto(s)
Cicatriz/metabolismo , Colágeno/metabolismo , Factor de Crecimiento de Hepatocito/metabolismo , Transfección , Factor de Crecimiento Transformador beta2/metabolismo , Animales , Proliferación Celular , Cicatriz/patología , Ratones , Modelos Animales , Ratas , Ratas Sprague-Dawley
12.
Forensic Sci Int ; 307: 110123, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31951950

RESUMEN

Forensic investigators commonly interpret bone fracture patterns to estimate the force required to generate that trauma. Unfortunately, these estimates are limited to qualitative values such as "mild", "moderate" or "extreme" force. This work presents a new experimental forensic device developed to simulate blunt- and sharp-force trauma injuries, while recording the forces and velocities involved, so that a more quantitative relationship between force and trauma can be established. The machine design is described in some detail, its capabilities are outlined, and the results of the commissioning and validation tests are presented. Preliminary results for both blunt- and sharp-force testing of porcine ribs, conducted at 3.8m/s, indicate the average peak force (733±95N versus 392±73N), average force (334±49N versus 101±24N), and work (2.34±0.26J versus 0.68±0.09J) are significantly higher in the blunt case. The experimental data generated by this instrumented device will allow forensic investigators to create a better quantitative link between incident conditions (velocity, force, work) and the resulting fracture patterns.


Asunto(s)
Antropología Forense/instrumentación , Costillas/lesiones , Heridas no Penetrantes/patología , Heridas Penetrantes/patología , Animales , Diseño de Equipo , Humanos , Modelos Animales , Costillas/patología , Porcinos
13.
Life Sci ; 244: 117281, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31926249

RESUMEN

AIMS: Mast cells play a crucial role in gastrointestinal physiology and pathophysiology. This study was conducted to investigate the role of mast cells (MCs) in the protective effect of Lactobacillus casei ATCC 393 (L. casei ATCC 393) on intestinal barrier function. MAIN METHODS: The regulatory effect of L. casei ATCC 393 on intestinal barrier dysfunction and MCs activation induced by Enterotoxigenic Escherichia coli K88 (ETEC K88) were evaluated by porcine mucosal mast cells (PMMCs)-porcine jejunal epithelial cells (IPEC-J2)-L. casei ATCC 393 co-culture experiments in vitro and MCs stabilizer drug experiment in vivo. KEY FINDINGS: Results showed that L. casei ATCC 393 pretreatment effectively alleviated the reduction of cell viability and increase of permeability in ETEC K88-infected IPEC-J2 cells. L. casei ATCC 393 pretreatment inhibited the increase of proinflammatory cytokines and some other MCs mediators, and decrease of anti-inflammatory cytokines in ETEC K88-infected PMMCs. Cromolyn sodium or L. casei ATCC 393 prevented ETEC K88-induced increase of intestinal epithelial cell permeability in IPEC-J2 cells when co-cultivation with PMMCs. Furthermore, cromolyn sodium or L. casei ATCC 393 pretreatment attenuated ETEC K88-induced increase of MCs mediators, mast cell proteases (MCPs) and carboxypeptidase A3 (CPA3) mRNA levels, and down-regulation of tight junction proteins, Toll-like receptor 2 and 4 (TLR2 and TLR4) expression levels in mice challenged by ETEC K88. SIGNIFICANCE: These results indicated that intestinal barrier dysfunction caused by ETEC K88 was mediated by intestinal mast cell activation which can be prevented by L. casei ATCC 393 via TLRs signaling pathway.


Asunto(s)
Mucosa Intestinal/metabolismo , Lactobacillus casei/metabolismo , Mastocitos/fisiología , Animales , Línea Celular , Supervivencia Celular , Escherichia coli Enterotoxigénica/metabolismo , Escherichia coli Enterotoxigénica/patogenicidad , Células Epiteliales/metabolismo , Infecciones por Escherichia coli/metabolismo , Enfermedades Gastrointestinales/metabolismo , Enfermedades Intestinales/metabolismo , Intestinos/fisiología , Masculino , Mastocitos/metabolismo , Ratones , Ratones Endogámicos C57BL , Modelos Animales , Porcinos , Receptores Toll-Like/metabolismo
14.
J Oral Sci ; 62(1): 62-66, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31996525

RESUMEN

This study was performed to develop a new rat model of reduced masticatory activity in order to assess the effect of this reduction on the morphology of the temporomandibular joint (TMJ) over time. Female rats were used, and ovariectomy was performed to simulate aged/postmenopausal status. Twenty-four SD rats aged 6 weeks were divided into four groups: ovariectomy/sham procedure (Ov/S); ovariectomy/reduced masticatory activity (Ov/RMA); non-Ov/S (NO/S); and non-Ov/RMA (NO/RMA). The RMA procedure involved grinding down the edges of the upper and mandibular incisors by about 3 mm and supplying the rats with a powdered diet. The bilateral TMJ was examined by micro-computed tomography at 0, 1, 2, 4, 6, and 8 weeks after the start of RMA. Condylar width was greater in the NO/S group than in the Ov/S group after the 2nd week, showing that ovariectomy reduced the width of the condyle. After the 2nd week, significant differences in condylar width were apparent between the NO/S and NO/RMA groups, and between the Ov/S and Ov/RMA groups. This RMA procedure appeared to provide a good model of reduced masticatory activity. The present findings in female rats suggest that reduction of appropriate mastication activity in the growth period results in poor growth of the mandibular condyle and immediately induces atrophy of the mandibular condyle under conditions simulating aged/postmenopausal status.


Asunto(s)
Cóndilo Mandibular , Masticación , Animales , Atrofia , Femenino , Modelos Animales , Ratas , Ratas Sprague-Dawley , Microtomografía por Rayos X
16.
Nat Commun ; 11(1): 175, 2020 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-31924752

RESUMEN

Challenges in drug development of neurological diseases remain mainly ascribed to the blood-brain barrier (BBB). Despite the valuable contribution of animal models to drug discovery, it remains difficult to conduct mechanistic studies on the barrier function and interactions with drugs at molecular and cellular levels. Here we present a microphysiological platform that recapitulates the key structure and function of the human BBB and enables 3D mapping of nanoparticle distributions in the vascular and perivascular regions. We demonstrate on-chip mimicry of the BBB structure and function by cellular interactions, key gene expressions, low permeability, and 3D astrocytic network with reduced reactive gliosis and polarized aquaporin-4 (AQP4) distribution. Moreover, our model precisely captures 3D nanoparticle distributions at cellular levels and demonstrates the distinct cellular uptakes and BBB penetrations through receptor-mediated transcytosis. Our BBB platform may present a complementary in vitro model to animal models for prescreening drug candidates for the treatment of neurological diseases.


Asunto(s)
Transporte Biológico/fisiología , Ingeniería Biomédica/métodos , Barrera Hematoencefálica/metabolismo , Dispositivos Laboratorio en un Chip , Nanopartículas/química , Nanotecnología/métodos , Animales , Acuaporina 4/metabolismo , Astrocitos/metabolismo , Ingeniería Biomédica/instrumentación , Técnicas de Cultivo de Célula/métodos , Sistemas de Liberación de Medicamentos , Descubrimiento de Drogas , Citometría de Flujo , Expresión Génica , Gliosis , Humanos , Modelos Animales , Nanotecnología/instrumentación , Permeabilidad , Transcitosis
17.
Pharm Res ; 37(3): 40, 2020 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-31970499

RESUMEN

PURPOSES: Senescence is an inevitable and irreversible process, which may lead to loss in muscle and bone density, decline in brain volume and loss in renal clearance. Although aging is a well-known process, few studies on the consumption of nanodrugs by elderly people were performed. METHODS: We evaluated three different nanosystems: i) carbon based nanosystem (Graphene Quantum Dots, GQD), ii) polymeric nanoparticles and mesoporous silica (magnetic core mesoporous silica, MMSN). In previous studies, our group has already characterized GQD and MMSN nanoparticles by dynamic light scattering analysis, atomic force microscopy, transmission electron microscopy, X-ray diffraction, Raman analysis, fluorescence and absorbance. The polymeric nanoparticle has been characterized by AFM and DLS. All the nanosystems were radiolabeled with 99 m-Tc by. The in vivo biodistribution/tissue deposition analysis evaluation was done using elder (PN270) and young (PN90) mice injected with radioactive nanosystems. RESULTS: The nanosystems used in this study were well-formed as the radiolabeling processes were stable. Biodistribution analysis showed that there is a decrease in the uptake of the nanoparticles in elder mice when compared to young mice, showing that is necessary to increase the initial dose in elder people to achieve the same concentration when compared to young animals. CONCLUSION: The discrepancy on tissue distribution of nanosystems between young and elder individuals must be monitored, as the therapeutic effect will be different in the groups. Noteworthy, this data is an alarm that some specific conditions must be evaluated before commercialization of nano-drugs. Graphical Abstract Changes between younger and elderly individuals are undoubtedly, especially in drug tissue deposition, biodistribution and pharmacokinetics. The same thought should be applied to nanoparticles. A comprehensive analysis on how age discrepancy change the biological behavior of nanoparticles has been performed.


Asunto(s)
Grafito/química , Nanopartículas/química , Nanopartículas/metabolismo , Poliésteres/química , Dióxido de Silicio/química , Factores de Edad , Animales , Marcaje Isotópico , Nanopartículas de Magnetita/química , Ratones , Modelos Animales , Nanopartículas/administración & dosificación , Tamaño de la Partícula , Porosidad , Propiedades de Superficie , Tecnecio/química , Distribución Tisular
18.
Adv Exp Med Biol ; 1217: 147-171, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31898227

RESUMEN

The CRL1 complex, also known as the SCF complex, is a ubiquitin ligase that in mammals consists of an adaptor protein (SKP1), a scaffold protein (CUL1), a RING finger protein (RBX1, also known as ROC1), and one of about 70 F-box proteins. Given that the F-box proteins determine the substrate specificity of the CRL1 complex, the variety of these proteins allows the generation of a large number of ubiquitin ligases that promote the degradation or regulate the function of many substrate proteins and thereby control numerous key cellular processes. The physiological and pathological functions of these many CRL1 ubiquitin ligases have been studied by the generation and characterization of knockout mouse models that lack specific CRL1 components. In this chapter, we provide a comprehensive overview of these mouse models and discuss the role of each CRL1 component in mouse physiology and pathology.


Asunto(s)
Proteínas Cullin/metabolismo , Proteínas Ligasas SKP Cullina F-box/metabolismo , Animales , Proteínas Cullin/química , Ratones , Ratones Noqueados , Modelos Animales , Complejos Multiproteicos/química , Complejos Multiproteicos/metabolismo , Proteínas Ligasas SKP Cullina F-box/química
19.
Int J Radiat Oncol Biol Phys ; 106(3): 612-620, 2020 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-31738948

RESUMEN

PURPOSE: The cone-beam computed tomography (CBCT)-guided small animal radiation research platform (SARRP) has provided unique opportunities to test radiobiologic hypotheses. However, CBCT is less adept to localize soft tissue targets growing in a low imaging contrast environment. Three-dimensional bioluminescence tomography (BLT) provides strong image contrast and thus offers an attractive solution. We introduced a novel and efficient BLT-guided conformal radiation therapy and demonstrated it in an orthotopic glioblastoma (GBM) model. METHODS AND MATERIALS: A multispectral BLT system was integrated with SARRP for radiation therapy (RT) guidance. GBM growth curve was first established by contrast CBCT/magnetic resonance imaging (MRI) to derive equivalent sphere as approximated gross target volume (aGTV). For BLT, mice were subject to multispectral bioluminescence imaging, followed by SARRP CBCT imaging and optical reconstruction. The CBCT image was acquired to generate anatomic mesh for the reconstruction and RT planning. To ensure high accuracy of the BLT-reconstructed center of mass (CoM) for target localization, we optimized the optical absorption coefficients µa by minimizing the distance between the CoMs of BLT reconstruction and contrast CBCT/MRI-delineated GBM volume. The aGTV combined with the uncertainties of BLT CoM localization and target volume determination was used to generate estimated target volume (ETV). For conformal irradiation procedure, the GBM was first localized by the predetermined ETV centered at BLT-reconstructed CoM, followed by SARRP radiation. The irradiation accuracy was qualitatively confirmed by pathologic staining. RESULTS: Deviation between CoMs of BLT reconstruction and contrast CBCT/MRI-imaged GBM is approximately 1 mm. Our derived ETV centered at BLT-reconstructed CoM covers >95% of the tumor volume. Using the second-week GBM as an example, the ETV-based BLT-guided irradiation can cover 95.4% ± 4.7% tumor volume at prescribed dose. The pathologic staining demonstrated the BLT-guided irradiated area overlapped well with the GBM location. CONCLUSIONS: The BLT-guided RT enables 3-dimensional conformal radiation for important orthotopic tumor models, which provides investigators a new preclinical research capability.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Mediciones Luminiscentes , Imagen Multimodal/métodos , Radioterapia Conformacional , Radioterapia Guiada por Imagen , Animales , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/radioterapia , Tomografía Computarizada de Haz Cónico/métodos , Medios de Contraste , Glioblastoma/diagnóstico por imagen , Glioblastoma/patología , Glioblastoma/radioterapia , Procesamiento de Imagen Asistida por Computador , Imagen Tridimensional/métodos , Mediciones Luminiscentes/instrumentación , Mediciones Luminiscentes/métodos , Imagen por Resonancia Magnética/métodos , Ratones , Ratones Endogámicos C57BL , Modelos Animales , Radioterapia Conformacional/instrumentación , Radioterapia Conformacional/métodos , Radioterapia Guiada por Imagen/instrumentación , Radioterapia Guiada por Imagen/métodos , Carga Tumoral
20.
J Trauma Acute Care Surg ; 88(2): 305-309, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31804421

RESUMEN

BACKGROUND: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a viable resuscitation approach for a subdiaphragmatic injury that can regulate arterial blood flow. On the other hand, the evaluation of venous or portal venous blood flow during REBOA remains insufficient because invasive cannulation or exposure of the vessel may affect the blood flow, and Doppler echography is highly operator-dependent. However, phase contrast magnetic resonance imaging has enabled accurate evaluation and noninvasive measurement. This study aimed to investigate the change of venous and portal venous blood flow during REBOA in a porcine model. METHODS: Seven pigs were anesthetized, and a REBOA catheter was placed. The blood flows of the inferior vena cava (IVC), hepatic vein (HV), portal vein (PV), and superior vena cava (SVC) were measured using phase contrast magnetic resonance imaging, in both the balloon deflated (no-REBOA) and fully balloon inflated (REBOA) states. Mean arterial pressure (MAP), central venous pressure, cardiac index, and systemic vascular resistance index were measured. RESULTS: The blood flows of the suprahepatic, infrahepatic, and distal IVC, HV, and PV in the no-REBOA state were 1.40 ± 0.36 L·min, 0.94 ± 0.16 L·min, 0.50 ± 0.19 L·min, 0.060 ± 0.018 L·min, and 0.32 ± 0.091 L·min, respectively. The blood flow of each section in the REBOA condition was significantly decreased at 0.41 ± 0.078 (33% of baseline), 0.15 ± 0.13 (15%), 0.043 ± 0.034 (9%), 0.029 ± 0.017 (37%), and 0.070 ± 0.034 L·min (21%), respectively. The blood flow of the SVC increased significantly in the REBOA condition (1.4 ± 0.63 L·min vs. 0.53 ± 0.14 L·min [257%]). Mean arterial pressure, central venous pressure, cardiac index, and systemic vascular resistance index were significantly increased after REBOA inflation. CONCLUSION: Resuscitative endovascular balloon occlusion of the aorta decreased blood flows of the IVC, HV, and PV and increased blood flow of the SVC. This result could be explained by the collateral flow from the lower body to the SVC. A better understanding of the effect of REBOA on the venous and portal venous systems may help control liver injury.


Asunto(s)
Oclusión con Balón/efectos adversos , Procedimientos Endovasculares/efectos adversos , Sistema Porta/fisiología , Flujo Sanguíneo Regional/fisiología , Resucitación/efectos adversos , Animales , Aorta/cirugía , Oclusión con Balón/métodos , Procedimientos Endovasculares/métodos , Femenino , Humanos , Hígado/irrigación sanguínea , Hígado/diagnóstico por imagen , Hígado/lesiones , Imagen por Resonancia Magnética , Masculino , Modelos Animales , Sistema Porta/diagnóstico por imagen , Resucitación/métodos , Choque Hemorrágico/etiología , Choque Hemorrágico/terapia , Porcinos , Porcinos Enanos
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