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1.
Plant Dis ; : PDIS12212666PDN, 2022 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-34978876
2.
Surg Innov ; 28(6): 679-687, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33745358

RESUMEN

Background. Incorporation of a poly-ε-caprolactone (PCL) scaffold in circular stapled anastomoses has been shown to increase the anastomotic tensile strength on postoperative day (POD) 5 in a pig model. The aim of this study was to investigate the effects of incorporation of a PCL scaffold in a circular stapled end-to-end small intestine anastomosis, with stricture formation and anastomotic histology as primary outcomes in a 30-day observation period. Methods. A total of 15 piglets were included. In each piglet, three circular stapled end-to-end anastomoses were made in the small intestines. Two were interventional and one was a control. On POD 10, 20, or 30, the anastomoses were subjected to in vivo intraluminal contrast study, and the index for anastomotic lumen was calculated. The anastomotic segment was resected and subjected to a tensile strength test and histological examination. Results. At POD 10, the mean ± SD value for anastomotic index was .749 ± .065 in control anastomoses and .637 ± .051 in interventional anastomosis (P = .0046), at POD 20, .541 ± .150 and .724 ± .07 (P = .051), and at POD 30, .645 ± .103 and .686 ± .057 (P = .341), respectively. No significant difference was observed in maximum tensile strength and histology at POD 30. Conclusions. The incorporation of a PCL scaffold in a circular stapled end-to-end small intestine anastomosis does not increase the risk of stricture or impair wound healing after 30 days.


Asunto(s)
Caproatos , Lactonas , Anastomosis Quirúrgica/efectos adversos , Animales , Intestino Delgado/cirugía , Grapado Quirúrgico/efectos adversos , Técnicas de Sutura , Porcinos
3.
Fungal Syst Evol ; 6: 243-252, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32904240

RESUMEN

Acacia mangium plantations account for more than 50 % of the exotic plantations in Vietnam. A new black butt symptom was discovered in 2012, followed by the wilting sign in Acacia seedlings in Tuyen Quang Province. Isolations recovered two Phytophthora species, the well-known Acacia pathogen P. cinnamomi, and an unknown species. The new species is described here as Phytophthora acaciivora sp. nov. Phylogenetically this species resides in clade 2d and is most closely related to P. frigida. Phytophthora acaciivora is a heterothallic species, oospores are aplerotic and antheridia are amphigynous. It produces predominantly elongated ovoid, semi papillate, persistent sporangia, no hyphal swellings and no chlamydospores. Optimum temperature for the growth is 25-30 °C and the maximum temperature is over 37.5 °C. Studies are underway to determine the impact of this new species on Acacia plantations in Vietnam.

4.
Am J Hum Genet ; 104(5): 847-860, 2019 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-31051113

RESUMEN

Collagen type IV alpha 1 and alpha 2 chains form heterotrimers ([α1(IV)]2α2(IV)) that represent a fundamental basement membrane constituent. Dominant COL4A1 and COL4A2 mutations cause a multisystem disorder that is marked by clinical heterogeneity and variable expressivity and that is generally characterized by the presence of cerebrovascular disease with ocular, renal, and muscular involvement. Despite the fact that muscle pathology is reported in up to one-third of individuals with COL4A1 and COL4A2 mutations and in animal models with mutations in COL4A1 and COL4A2 orthologs, the pathophysiological mechanisms underlying COL4A1-related myopathy are unknown. In general, mutations are thought to impair [α1(IV)]2α2(IV) secretion. Whether pathogenesis results from intracellular retention, extracellular deficiency, or the presence of mutant proteins in basement membranes represents an important gap in knowledge and a major obstacle for developing targeted interventions. We report that Col4a1 mutant mice develop progressive neuromuscular pathology that models human disease. We demonstrate that independent muscular, neural, and vascular insults contribute to neuromyopathy and that there is mechanistic heterogeneity among tissues. Importantly, we provide evidence of a COL4A1 functional subdomain with disproportionate significance for tissue-specific pathology and demonstrate that a potential therapeutic strategy aimed at promoting [α1(IV)]2α2(IV) secretion can ameliorate or exacerbate myopathy in a mutation-dependent manner. These data have important translational implications for prediction of clinical outcomes based on genotype, development of mechanism-based interventions, and genetic stratification for clinical trials. Collectively, our data underscore the importance of the [α1(IV)]2α2(IV) network as a multifunctional signaling platform and show that allelic and tissue-specific mechanistic heterogeneities contribute to the variable expressivity of COL4A1 and COL4A2 mutations.


Asunto(s)
Colágeno Tipo IV/genética , Enfermedades Musculares/etiología , Mutación , Enfermedades Neuromusculares/etiología , Animales , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Enfermedades Musculares/patología , Enfermedades Neuromusculares/patología , Especificidad de Órganos , Fenotipo
5.
Mol Ther ; 26(2): 593-605, 2018 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-29331291

RESUMEN

Bone remodeling and regeneration are highly regulated multistep processes involving posttranscriptional regulation by microRNAs (miRNAs). Here, we performed a global profiling of differentially expressed miRNAs in bone-marrow-derived skeletal cells (BMSCs; also known as stromal or mesenchymal stem cells) during in vitro osteoblast differentiation. We functionally validated the regulatory effects of several miRNAs on osteoblast differentiation and identified 15 miRNAs, most significantly miR-222 and miR-423, as regulators of osteoblastogenesis. In addition, we tested the possible targeting of miRNAs for enhancing bone tissue regeneration. Scaffolds functionalized with miRNA nano-carriers enhanced osteoblastogenesis in 3D culture and retained this ability at least 2 weeks after storage. Additionally, anti-miR-222 enhanced in vivo ectopic bone formation through targeting the cell-cycle inhibitor CDKN1B (cyclin-dependent kinase inhibitor 1B). A number of additional miRNAs exerted additive osteoinductive effects on BMSC differentiation, suggesting that pools of miRNAs delivered locally from an implanted scaffold can provide a promising approach for enhanced bone regeneration.


Asunto(s)
Regeneración Ósea/genética , Perfilación de la Expresión Génica , Células Madre Mesenquimatosas/metabolismo , MicroARNs/genética , Transcriptoma , Regiones no Traducidas 3' , Antagomirs/genética , Biomarcadores , Ciclo Celular/genética , Diferenciación Celular/genética , Línea Celular , Biología Computacional/métodos , Expresión Génica Ectópica , Regulación de la Expresión Génica , Técnicas de Transferencia de Gen , Humanos , Osteogénesis/genética
6.
Brain ; 141(1): 85-98, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29244098

RESUMEN

Hypoxia can injure brain white matter tracts, comprised of axons and myelinating oligodendrocytes, leading to cerebral palsy in neonates and delayed post-hypoxic leukoencephalopathy (DPHL) in adults. In these conditions, white matter injury can be followed by myelin regeneration, but myelination often fails and is a significant contributor to fixed demyelinated lesions, with ensuing permanent neurological injury. Non-myelinating oligodendrocyte precursor cells are often found in lesions in plentiful numbers, but fail to mature, suggesting oligodendrocyte precursor cell differentiation arrest as a critical contributor to failed myelination in hypoxia. We report a case of an adult patient who developed the rare condition DPHL and made a nearly complete recovery in the setting of treatment with clemastine, a widely available antihistamine that in preclinical models promotes oligodendrocyte precursor cell differentiation. This suggested possible therapeutic benefit in the more clinically prevalent hypoxic injury of newborns, and we demonstrate in murine neonatal hypoxic injury that clemastine dramatically promotes oligodendrocyte precursor cell differentiation, myelination, and improves functional recovery. We show that its effect in hypoxia is oligodendroglial specific via an effect on the M1 muscarinic receptor on oligodendrocyte precursor cells. We propose clemastine as a potential therapy for hypoxic brain injuries associated with white matter injury and oligodendrocyte precursor cell maturation arrest.


Asunto(s)
Clemastina/uso terapéutico , Enfermedades Desmielinizantes/tratamiento farmacológico , Enfermedades Desmielinizantes/etiología , Antagonistas de los Receptores Histamínicos H1/uso terapéutico , Hipoxia Encefálica/complicaciones , Recuperación de la Función/efectos de los fármacos , Potenciales de Acción/efectos de los fármacos , Animales , Animales Recién Nacidos , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Cerebelo/efectos de los fármacos , Cerebelo/metabolismo , Cerebelo/ultraestructura , Enfermedades Desmielinizantes/diagnóstico por imagen , Enfermedades Desmielinizantes/patología , Modelos Animales de Enfermedad , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Humanos , Hipoxia Encefálica/diagnóstico por imagen , Masculino , Ratones , Ratones Noqueados , Persona de Mediana Edad , Vaina de Mielina/efectos de los fármacos , Vaina de Mielina/ultraestructura , Células Precursoras de Oligodendrocitos/efectos de los fármacos , Nervio Óptico/fisiopatología , Oxígeno/farmacología , Receptor Muscarínico M1/genética , Receptor Muscarínico M1/metabolismo
7.
Cell Rep ; 21(10): 2678-2687, 2017 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-29212016

RESUMEN

A deletion or duplication in the 16p11.2 region is associated with neurodevelopmental disorders, including autism spectrum disorder and schizophrenia. In addition to clinical characteristics, carriers of the 16p11.2 copy-number variant (CNV) manifest opposing neuroanatomical phenotypes-e.g., macrocephaly in deletion carriers (16pdel) and microcephaly in duplication carriers (16pdup). Using fibroblasts obtained from 16pdel and 16pdup carriers, we generated induced pluripotent stem cells (iPSCs) and differentiated them into neurons to identify causal cellular mechanisms underlying neurobiological phenotypes. Our study revealed increased soma size and dendrite length in 16pdel neurons and reduced neuronal size and dendrite length in 16pdup neurons. The functional properties of iPSC-derived neurons corroborated aspects of these contrasting morphological differences that may underlie brain size. Interestingly, both 16pdel and 16pdup neurons displayed reduced synaptic density, suggesting that distinct mechanisms may underlie brain size and neuronal connectivity at this locus.


Asunto(s)
Trastorno del Espectro Autista/metabolismo , Trastorno Autístico/metabolismo , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/metabolismo , Neuronas/citología , Neuronas/metabolismo , Trastorno del Espectro Autista/genética , Trastorno Autístico/genética , Diferenciación Celular/genética , Diferenciación Celular/fisiología , Deleción Cromosómica , Duplicación Cromosómica/genética , Cromosomas Humanos Par 16/genética , Variaciones en el Número de Copia de ADN/genética , Humanos , Megalencefalia/genética , Megalencefalia/metabolismo , Microcefalia/genética , Microcefalia/metabolismo , Modelos Genéticos
8.
Neoplasma ; 64(4): 518-525, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28485157

RESUMEN

The study aimed to explore the effect of Saikosaponin-d (SSd) and its underlying mechanism on cell growth inhibition as well as induction of apoptosis and cell cycle arrest in renal cell carcinoma (RCC). MTT assay and colony formation assay were employed in this study, with the results indicating that RCC cells proliferation was inhibited by SSd at different doses. Analysis by flow cytometry revealed that RCC cell proliferation inhibitory effect of SSd was achieved by inducing apoptosis and cell cycle arrest at G0/G1 phase via up-regulation of p53. As compared to the control group, SSd can significantly inhibit the growth of 769-P and 786-O cell lines and induce apoptosis and cell cycle arrest. The mechanism exploration demonstrated that inhibiting the activation of EGFR/p38 signaling pathways was the molecular basis of SSd's biological effects such as inducing apoptotic death, inhibiting cell growth as well as up-regulating p53 expression in human RCC cells. In conclusion, our data suggest that SSd may serve as a promising intervention for chemopreventive or chemotherapeutic treatment for patients with RCC.


Asunto(s)
Carcinoma de Células Renales/patología , Neoplasias Renales/patología , Sistema de Señalización de MAP Quinasas , Ácido Oleanólico/análogos & derivados , Saponinas/farmacología , Apoptosis , Carcinoma de Células Renales/tratamiento farmacológico , Puntos de Control del Ciclo Celular , Línea Celular Tumoral , Proliferación Celular , Receptores ErbB/metabolismo , Humanos , Neoplasias Renales/tratamiento farmacológico , Ácido Oleanólico/farmacología , Proteína p53 Supresora de Tumor/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
9.
J Biomed Mater Res A ; 104(12): 3073-3081, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27490738

RESUMEN

Cells constantly sense and receive chemical and physical signals from neighboring cells, interstitial fluid, and extracellular matrix, which they integrate and translate into intracellular responses. Thus, the nature of the surface on which cells are cultured in vitro plays an important role for cell adhesion, proliferation, and differentiation. Autologs chondrocyte implantation is considered the treatment of choice for larger cartilage defects in the knee. To obtain a sufficient number of chondrocytes for implantation multiple passaging is often needed, which raises concerns about the changes in the chondrogenic phenotype. In the present study, we analyzed the effect at cellular and molecular level of precipitant induced porosity augmentation (PIPA) of polystyrene surfaces on proliferation and differentiation of human chondrocytes. Human chondrocytes were isolated from healthy patients undergoing anterior cruciate ligament reconstruction and cultured on PIPA modified polystyrene surfaces. Microscopical analysis revealed topographically arranged porosity with micron pores and nanometer pits. Chondrocytes cultured on PIPA surfaces revealed no difference in cell viability and proliferation, but gene- and protein expressions of collagen type II were pronounced in the first passage of chondrocytes when compared to chondrocytes cultured on control surfaces. Additionally, an analysis of 40 kinases revealed that chondrocytes expanded on PIPA caused upregulated PI3K/mTOR pathway activation and inhibition of mTORC1 resulted in reduced sGAG synthesis. These findings indicate that PIPA modified polystyrene preserved the chondrogenicity of expanded human chondrocytes at gene and protein levels, which clinically may be attractive for the next generation of cell-culture surfaces for ex vivo cell growth. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 3073-3081, 2016.


Asunto(s)
Materiales Biocompatibles/química , Precipitación Química , Condrocitos/citología , Condrogénesis , Dioxanos/química , Poliestirenos/química , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Condrocitos/metabolismo , Regulación de la Expresión Génica , Humanos , Porosidad , Proteínas Quinasas/metabolismo , Propiedades de Superficie
10.
J Neurosci ; 36(26): 6937-48, 2016 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-27358452

RESUMEN

UNLABELLED: Myelin controls the time required for an action potential to travel from the neuronal soma to the axon terminal, defining the temporal manner in which information is processed within the CNS. The presence of myelin, the internodal length, and the thickness of the myelin sheath are powerful structural factors that control the velocity and fidelity of action potential transmission. Emerging evidence indicates that myelination is sensitive to environmental experience and neuronal activity. Activity-dependent modulation of myelination can dynamically alter action potential conduction properties but direct functional in vivo evidence and characterization of the underlying myelin changes is lacking. We demonstrate that in mice long-term monocular deprivation increases oligodendrogenesis in the retinogeniculate pathway but shortens myelin internode lengths without affecting other structural properties of myelinated fibers. We also demonstrate that genetically attenuating synaptic glutamate neurotransmission from retinal ganglion cells phenocopies the changes observed after monocular deprivation, suggesting that glutamate may constitute a signal for myelin length regulation. Importantly, we demonstrate that visual deprivation and shortened internodes are associated with a significant reduction in nerve conduction velocity in the optic nerve. Our results reveal the importance of sensory input in the building of myelinated fibers and suggest that this activity-dependent alteration of myelination is important for modifying the conductive properties of brain circuits in response to environmental experience. SIGNIFICANCE STATEMENT: Oligodendrocyte precursor cells differentiate into mature oligodendrocytes and are capable of ensheathing axons with myelin without molecular cues from neurons. However, this default myelination process can be modulated by changes in neuronal activity. Here, we show, for the first time, that experience-dependent activity modifies the length of myelin internodes along axons altering action potential conduction velocity. Such a mechanism would allow for variations in conduction velocities that provide a degree of plasticity in accordance to environmental needs. It will be important in future work to investigate how these changes in myelination and conduction velocity contribute to signal integration in postsynaptic neurons and circuit function.


Asunto(s)
Fibras Nerviosas Mielínicas/fisiología , Conducción Nerviosa/fisiología , Nervio Óptico/fisiología , Visión Monocular/fisiología , Vías Visuales/fisiología , Potenciales de Acción/fisiología , Factores de Edad , Animales , Animales Recién Nacidos , Antígenos/genética , Antígenos/metabolismo , Toxina del Cólera/metabolismo , Cuerpos Geniculados/citología , Cuerpos Geniculados/fisiología , Cuerpos Geniculados/ultraestructura , Proteínas con Homeodominio LIM/genética , Proteínas con Homeodominio LIM/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Vaina de Mielina/metabolismo , Vaina de Mielina/ultraestructura , Fibras Nerviosas Mielínicas/ultraestructura , Conducción Nerviosa/genética , Nervio Óptico/ultraestructura , Organogénesis/genética , Organogénesis/fisiología , Estimulación Luminosa , Proteoglicanos/genética , Proteoglicanos/metabolismo , Células Ganglionares de la Retina/metabolismo , Transmisión Sináptica/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteína 2 de Transporte Vesicular de Glutamato/genética , Proteína 2 de Transporte Vesicular de Glutamato/metabolismo , Vías Visuales/ultraestructura
11.
Biores Open Access ; 4(1): 363-73, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26487981

RESUMEN

Bone tissue engineering requires a well-designed scaffold that can be biodegradable, biocompatible, and support the stem cells to osteogenic differentiation. Porous polycaprolactone (PCL) scaffold prepared by fused deposition modeling is an attractive biomaterial that has been used in clinic. However, PCL scaffolds lack biological function and osteoinductivity. In this study, we functionalized the PCL scaffolds by embedding them with a matrix of hyaluronic acid/ß-tricalcium phosphate (HA/TCP). Human mesenchymal stem cells (MSCs) were cultured on scaffolds with and without coating to investigate proliferation and osteogenic differentiation. The DNA amount was significantly higher in the HA/TCP-coated scaffold on day 21. At the gene expression level, HA/TCP coating significantly increased the expression of ALP and COLI on day 4. These data correlated with the ALP activity peaking on day 7 in the HA/TCP-coated scaffold. Scanning electron microscope and histological analysis revealed that the cell matrix and calcium deposition were distributed more uniformly in the coated scaffolds compared to scaffolds without coating. In conclusion, the HA/TCP coating improved cellular proliferation, osteogenic differentiation, and uniform distribution of the cellular matrix in vitro. The HA/TCP-PCL scaffold holds great promise to accommodate human bone marrow-derived MSCs for bone reconstruction purposes, which warrants future in vivo studies.

12.
Placenta ; 36(9): 1059-61, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26238804

RESUMEN

Arterioarterial (AA) and venovenous (VV) anastomoses in monochorionic (MC) placentas lie on the placental surface and are termed as superficial anastomoses. The purpose of this study is to report the occurrence of an atypical form of superficial anastomoses which are partially hidden. Partially-hidden superficial anastomoses were defined as vascular anastomoses without visible direct connection on placental surface but with clear mixing of dye after colored dye injection. With analyzing 270 MC placentas, we found a prevalence of partially-hidden AA and VV anastomose of 3% and 5%, respectively. In conclusion, partially-hidden superficial anastomose are not infrequent in MC placentas.


Asunto(s)
Placenta/irrigación sanguínea , Embarazo Gemelar , Gemelos Monocigóticos , Fístula Arterio-Arterial/patología , Femenino , Humanos , Placenta/patología , Embarazo
13.
Nat Commun ; 5: 4991, 2014 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-25255972

RESUMEN

The Schwann cell (SC)-axon interface represents a membrane specialization that integrates axonal signals to coordinate cytoskeletal dynamics resulting in myelination. Here we show that LKB1/Par-4 is asymmetrically localized to the SC-axon interface and co-localizes with the polarity protein Par-3. Using purified SCs and myelinating cocultures, we demonstrate that localization is dependent on the phosphorylation of LKB1 at serine-431. SC-specific deletion of LKB1 significantly attenuates developmental myelination, delaying the initiation and altering the myelin extent into adulthood, resulting in a 30% reduction in the conduction velocity along the adult sciatic nerves. Phosphorylation of LKB1 by protein kinase A is essential to establish the asymmetric localization of LKB1 and Par-3 and rescues the delay in myelination observed in the SC-specific knockout of LKB1. Our findings suggest that SC polarity may coordinate multiple signalling complexes that couple SC-axon contact to the redistribution of specific membrane components necessary to initiate and control myelin extent.


Asunto(s)
Polaridad Celular , Vaina de Mielina/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Células de Schwann/citología , Células de Schwann/enzimología , Proteínas Quinasas Activadas por AMP , Proteínas Adaptadoras Transductoras de Señales , Secuencias de Aminoácidos , Animales , Moléculas de Adhesión Celular/genética , Moléculas de Adhesión Celular/metabolismo , Proteínas de Ciclo Celular , Células Cultivadas , Ratones , Ratones Noqueados , Fosforilación , Proteínas Serina-Treonina Quinasas/química , Proteínas Serina-Treonina Quinasas/genética , Ratas , Células de Schwann/metabolismo
14.
J Neurosci ; 34(12): 4273-84, 2014 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-24647947

RESUMEN

The medial habenula (MHb) densely expresses nicotinic acetylcholine receptors (nAChRs) and participates in nicotine-related behaviors such as nicotine withdrawal and regulating nicotine intake. Although specific nAChR subunits are identified as being involved in withdrawal behavior, the cellular mechanisms through which nicotine acts to cause this aversive experience is unclear. Here, we demonstrate an interaction between the nicotinic and neurokinin signaling systems that may form the basis for some symptoms experienced during nicotine withdrawal. Using patch-clamp electrophysiology in mouse brain slices, we show that nicotine (1 µm) increases intrinsic excitability in MHb neurons. This nicotine-induced phenomenon requires α5-containing nAChRs and depends on intact neurokinin signaling. The effect is blocked by preincubation with neurokinin 1 (NK1; L-732138, 10 µm) and NK3 (SB222200, 2 µm) antagonists and mimicked by NK1 (substance P, 100 nm) and NK3 (neurokinin B [NKB], 100 nm) agonists. Microinjections (1 µl) of L-732138 (50 nm) and SB222200 (100 nm) into the MHb induces withdrawal behavior in chronic nicotine-treated (8.4 mg/kg/d, 2 weeks) mice. Conversely, withdrawal behavior is absent with analogous microinjections into the lateral habenula of nicotine-treated mice or in mice chronically treated with a vehicle solution. Further, chronic nicotine reduces nicotine's acute modulation of intrinsic excitability while sparing modulation by NKB. Our work elucidates the interplay between two neuromodulatory signaling systems in the brain through which nicotine acts to influence intrinsic excitability. More importantly, we document a neuroadaptation of this mechanism to chronic nicotine exposure and implicate these mechanisms collectively in the emergence of nicotine withdrawal behavior.


Asunto(s)
Habénula/efectos de los fármacos , Neuronas/efectos de los fármacos , Nicotina/farmacología , Receptores de Neuroquinina-1/metabolismo , Receptores de Neuroquinina-3/metabolismo , Transducción de Señal/efectos de los fármacos , Potenciales de Acción/efectos de los fármacos , Animales , Femenino , Habénula/citología , Habénula/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Neuroquinina B/farmacología , Antagonistas del Receptor de Neuroquinina-1/farmacología , Neuronas/citología , Neuronas/metabolismo , Receptores de Neuroquinina-3/antagonistas & inhibidores , Receptores Nicotínicos/metabolismo , Sustancia P/farmacología , Síndrome de Abstinencia a Sustancias/metabolismo
15.
Sci Rep ; 3: 2243, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23873182

RESUMEN

We describe a simple method for bone engineering using biodegradable scaffolds with mesenchymal stem cells derived from human induced-pluripotent stem cells (hiPS-MSCs). The hiPS-MSCs expressed mesenchymal markers (CD90, CD73, and CD105), possessed multipotency characterized by tri-lineages differentiation: osteogenic, adipogenic, and chondrogenic, and lost pluripotency - as seen with the loss of markers OCT3/4 and TRA-1-81 - and tumorigenicity. However, these iPS-MSCs are still positive for marker NANOG. We further explored the osteogenic potential of the hiPS-MSCs in synthetic polymer polycaprolactone (PCL) scaffolds or PCL scaffolds functionalized with natural polymer hyaluronan and ceramic TCP (PHT) both in vitro and in vivo. Our results showed that these iPS-MSCs are functionally compatible with the two 3D scaffolds tested and formed typically calcified structure in the scaffolds. Overall, our results suggest the iPS-MSCs derived by this simple method retain fully osteogenic function and provide a new solution towards personalized orthopedic therapy in the future.


Asunto(s)
Células Madre Mesenquimatosas/metabolismo , Osteogénesis/fisiología , Andamios del Tejido , Animales , Calcificación Fisiológica , Técnicas de Cultivo de Célula , Diferenciación Celular , Linaje de la Célula , Fibroblastos/citología , Regulación de la Expresión Génica , Humanos , Inmunofenotipificación , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/metabolismo , Cariotipo , Células Madre Mesenquimatosas/citología , Ratones , Osteoblastos/citología , Osteoblastos/metabolismo , Fenotipo , ARN Mensajero/genética , Factores de Tiempo
16.
Br J Pharmacol ; 169(3): 493-511, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23488589

RESUMEN

High-density lipoproteins (HDLs) represent a family of particles characterized by the presence of apolipoprotein A-I (apoA-I) and by their ability to transport cholesterol from peripheral tissues back to the liver. In addition to this function, HDLs display pleiotropic effects including antioxidant, anti-apoptotic, anti-inflammatory, anti-thrombotic or anti-proteolytic properties that account for their protective action on endothelial cells. Vasodilatation via production of nitric oxide is also a hallmark of HDL action on endothelial cells. Endothelial cells express receptors for apoA-I and HDLs that mediate intracellular signalling and potentially participate in the internalization of these particles. In this review, we will detail the different effects of HDLs on the endothelium in normal and pathological conditions with a particular focus on the potential use of HDL therapy to restore endothelial function and integrity.


Asunto(s)
Endotelio Vascular/metabolismo , Lipoproteínas HDL/metabolismo , Modelos Biológicos , Receptores de Lipoproteína/metabolismo , Vasculitis/metabolismo , Animales , Apoptosis , Transporte Biológico , Barrera Hematoencefálica/metabolismo , Angiopatías Diabéticas/inmunología , Angiopatías Diabéticas/metabolismo , Angiopatías Diabéticas/fisiopatología , Angiopatías Diabéticas/terapia , Sistemas de Liberación de Medicamentos , Endotelio Vascular/inmunología , Endotelio Vascular/fisiopatología , Humanos , Lipoproteínas HDL/sangre , Lipoproteínas HDL/uso terapéutico , Lisofosfolípidos , Esfingosina/análogos & derivados , Vasculitis/inmunología , Vasculitis/fisiopatología , Vasculitis/terapia
17.
Int J Pharm ; 448(1): 214-20, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23538094

RESUMEN

Little is known about the interaction between antineoplastic drugs and implants in bone cancer patients. We investigated the interaction between commercially available porous tantalum (Ta) implants and the chemotherapeutic drug, Doxorubicin (DOX). DOX solutions were prepared in the presence of Ta implant. The changes in fluorescence intensity of the DOX chromophore were measured by spectrofluorometry and the efficacy of DOX was evaluated by viability of rabbit rectal tumor cells (VX2). After 5 min interaction of the DOX solution (5 µg/ml) with the Ta implant, the fluorescent intensity of the DOX solution was 85% degraded, and only 20% the drug efficacy to kill VX2 cells was retained. However, after adding a reducing agent, Dithiothreitol (DTT, 10 µg/ml), 80% of the original fluorescence and 50% of the drug efficacy were restored while UV irradiation enhanced drug degradation in the presence of Ta implant. The action of DTT and UV irradiation indicated that reactive oxygen species (ROS) were involved in the drug degradation mechanism. We detected that Ta implants in aqueous medium produced hydroxyl radicals. Cells showed higher intracellular ROS activity when culture medium was incubated with the Ta implant prior to cell culture. It is concluded that the porous Ta implant antagonizes the cytotoxicity of DOX via ROS generation of the porous Ta implant.


Asunto(s)
Antibióticos Antineoplásicos/química , Doxorrubicina/química , Prótesis e Implantes , Especies Reactivas de Oxígeno/química , Tantalio/química , Animales , Antibióticos Antineoplásicos/farmacología , Antibióticos Antineoplásicos/efectos de la radiación , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ditiotreitol/farmacología , Doxorrubicina/farmacología , Doxorrubicina/efectos de la radiación , Conejos , Especies Reactivas de Oxígeno/metabolismo , Rayos Ultravioleta
18.
Int J Nanomedicine ; 7: 4285-97, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22904634

RESUMEN

Bone tissue engineering implants with sustained local drug delivery provide an opportunity for better postoperative care for bone tumor patients because these implants offer sustained drug release at the tumor site and reduce systemic side effects. A rapid prototyped macroporous polycaprolactone scaffold was embedded with a porous matrix composed of chitosan, nanoclay, and ß-tricalcium phosphate by freeze-drying. This composite scaffold was evaluated on its ability to deliver an anthracycline antibiotic and to promote formation of mineralized matrix in vitro. Scanning electronic microscopy, confocal imaging, and DNA quantification confirmed that immortalized human bone marrow-derived mesenchymal stem cells (hMSC-TERT) cultured in the scaffold showed high cell viability and growth, and good cell infiltration to the pores of the scaffold. Alkaline phosphatase activity and osteocalcin staining showed that the scaffold was osteoinductive. The drug-release kinetics was investigated by loading doxorubicin into the scaffold. The scaffolds comprising nanoclay released up to 45% of the drug for up to 2 months, while the scaffold without nanoclay released 95% of the drug within 4 days. Therefore, this scaffold can fulfill the requirements for both bone tissue engineering and local sustained release of an anticancer drug in vitro. These results suggest that the scaffold can be used clinically in reconstructive surgery after bone tumor resection. Moreover, by changing the composition and amount of individual components, the scaffold can find application in other tissue engineering areas that need local sustained release of drug.


Asunto(s)
Sistemas de Liberación de Medicamentos/instrumentación , Sistemas de Liberación de Medicamentos/métodos , Nanoestructuras/química , Ingeniería de Tejidos/instrumentación , Ingeniería de Tejidos/métodos , Andamios del Tejido , Fosfatasa Alcalina/química , Silicatos de Aluminio/química , Análisis de Varianza , Materiales Biocompatibles/química , Regeneración Ósea , Calcio/química , Fosfatos de Calcio/química , Línea Celular Transformada , Fenómenos Fisiológicos Celulares , Quitosano/química , Arcilla , Preparaciones de Acción Retardada , Histocitoquímica , Humanos , Células Madre Mesenquimatosas/citología , Osteogénesis , Poliésteres/química
19.
Mucosal Immunol ; 5(6): 646-57, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22643849

RESUMEN

Human immunodeficiency virus (HIV) and Simian immunodeficiency virus (SIV) disease progression is associated with multifocal damage to the gastrointestinal tract epithelial barrier that correlates with microbial translocation and persistent pathological immune activation, but the underlying mechanisms remain unclear. Investigating alterations in mucosal immunity during SIV infection, we found that damage to the colonic epithelial barrier was associated with loss of multiple lineages of interleukin (IL)-17-producing lymphocytes, cells that microarray analysis showed expressed genes important for enterocyte homeostasis, including IL-22. IL-22-producing lymphocytes were also lost after SIV infection. Potentially explaining coordinate loss of these distinct populations, we also observed loss of CD103+ dendritic cells (DCs) after SIV infection, which associated with the loss of IL-17- and IL-22-producing lymphocytes. CD103+ DCs expressed genes associated with promotion of IL-17/IL-22+ cells, and coculture of CD103+ DCs and naïve T cells led to increased IL17A and RORc expression in differentiating T cells. These results reveal complex interactions between mucosal immune cell subsets providing potential mechanistic insights into mechanisms of mucosal immune dysregulation during HIV/SIV infection, and offer hints for development of novel therapeutic strategies to address this aspect of AIDS virus pathogenesis.


Asunto(s)
Colon/inmunología , Células Dendríticas/inmunología , Enterocitos/inmunología , Inmunidad Mucosa , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Virus de la Inmunodeficiencia de los Simios/fisiología , Células Th17/inmunología , Animales , Antígenos CD/inmunología , Diferenciación Celular , Linaje de la Célula , Técnicas de Cocultivo , Colon/patología , Colon/virología , Células Dendríticas/patología , Células Dendríticas/virología , Enterocitos/patología , Enterocitos/virología , Regulación de la Expresión Génica , Cadenas alfa de Integrinas/deficiencia , Cadenas alfa de Integrinas/inmunología , Interleucina-17/deficiencia , Interleucina-17/genética , Interleucina-17/inmunología , Interleucinas/deficiencia , Interleucinas/genética , Interleucinas/inmunología , Macaca mulatta , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/patología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Células Th17/patología , Células Th17/virología , Interleucina-22
20.
Comput Aided Surg ; 16(3): 135-42, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21381889

RESUMEN

INTRODUCTION: Advances in surgical navigation have opened new possibilities for lumbosacral interbody fusion procedures. We have designed a novel navigated surgical method, Navigated Percutaneous Lumbosacral Interbody Fusion (NPLSIF), that enables lumbosacral discectomy and bone grafting to be performed percutaneously and safely. METHODS: To prove that NPLSIF is feasible from an anatomical perspective, it was simulated on 3D models of the lumbosacral spine created using CT data from 60 patients. Feasibility would be verified if both the working corridor and the S1 pedicle screw could be accommodated in the sacral ala without overlapping and without penetrating either the spinal canal or the anterior or upper sacral wall. In addition, the discectomy that could be achieved using NPLSIF was evaluated, and a surgical experiment was performed using a plastic torso model. RESULTS: The 3D modeling and surgical simulation were successfully completed in all cases. The feasibility of the NPLSIF approach was verified in every case, i.e., both the working corridor and the S1 pedicle screw were accommodated in the sacral ala without overlapping and without penetrating either the spinal canal or the anterior or upper sacral wall. The mean ratio of the area of discectomy that could be achieved by NPLSIF to the total area of the lumbosacral disc was 0.721 ± 0.065 (range: 0.57-0.894), 0.956 ± 0.045 (range: 0.8-1.0) and 0.945 ± 0.058 (range: 0.813-1.0) in the axial, coronal and sagittal planes, respectively. NPLSIF was also successfully executed on the plastic torso model. Preoperative planning on the navigation workstation took 5 minutes and each intraoperative CT scan took 30 seconds. Locating the entry point of the working corridor according to the preoperative plan took 3 minutes. Postoperative CT images and direct viewing of the plastic model revealed no penetration of the spinal canal or sacral wall. CONCLUSION: The feasibility of Navigated Percutaneous Lumbosacral Interbody Fusion (NPLSIF) was verified from an anatomical perspective. We also demonstrated that an adequate discectomy can be achieved using the procedure. Cadaveric experiments and clinical trials are needed to further evaluate the efficacy and efficiency of NPLSIF.


Asunto(s)
Discectomía Percutánea/instrumentación , Vértebras Lumbares/cirugía , Sacro/cirugía , Fusión Vertebral/instrumentación , Cirugía Asistida por Computador/instrumentación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Tornillos Óseos , Trasplante Óseo/instrumentación , Trasplante Óseo/métodos , Discectomía Percutánea/métodos , Estudios de Factibilidad , Femenino , Humanos , Imagenología Tridimensional , Vértebras Lumbares/patología , Masculino , Persona de Mediana Edad , Sacro/patología , Fusión Vertebral/métodos , Cirugía Asistida por Computador/métodos , Adulto Joven
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