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1.
Proc Natl Acad Sci U S A ; 119(3)2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-35027452

RESUMEN

Alzheimer's disease (AD) is characterized by complex, multifactorial neuropathology, suggesting that small molecules targeting multiple neuropathological factors are likely required to successfully impact clinical progression. Acid sphingomyelinase (ASM) activation has been recognized as an important contributor to these neuropathological features in AD, leading to the concept of using ASM inhibitors for the treatment of this disorder. Here we report the identification of KARI 201, a direct ASM inhibitor evaluated for AD treatment. KARI 201 exhibits highly selective inhibition effects on ASM, with excellent pharmacokinetic properties, especially with regard to brain distribution. Unexpectedly, we found another role of KARI 201 as a ghrelin receptor agonist, which also has therapeutic potential for AD treatment. This dual role of KARI 201 in neurons efficiently rescued neuropathological features in AD mice, including amyloid beta deposition, autophagy dysfunction, neuroinflammation, synaptic loss, and decreased hippocampal neurogenesis and synaptic plasticity, leading to an improvement in memory function. Our data highlight the possibility of potential clinical application of KARI 201 as an innovative and multifaceted drug for AD treatment.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Neuropatología/métodos , Animales , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Hipocampo/metabolismo , Hipocampo/patología , Memoria , Ratones , Plasticidad Neuronal , Neuronas/metabolismo , Receptores de Ghrelina/metabolismo , Esfingomielina Fosfodiesterasa/genética , Esfingomielina Fosfodiesterasa/metabolismo
2.
Proc Natl Acad Sci U S A ; 116(47): 23426-23436, 2019 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-31685616

RESUMEN

As a central feature of neuroinflammation, microglial dysfunction has been increasingly considered a causative factor of neurodegeneration implicating an intertwined pathology with amyloidogenic proteins. Herein, we report the smallest synthetic molecule (N,N'-diacetyl-p-phenylenediamine [DAPPD]), simply composed of a benzene ring with 2 acetamide groups at the para position, known to date as a chemical reagent that is able to promote the phagocytic aptitude of microglia and subsequently ameliorate cognitive defects. Based on our mechanistic investigations in vitro and in vivo, 1) the capability of DAPPD to restore microglial phagocytosis is responsible for diminishing the accumulation of amyloid-ß (Aß) species and significantly improving cognitive function in the brains of 2 types of Alzheimer's disease (AD) transgenic mice, and 2) the rectification of microglial function by DAPPD is a result of its ability to suppress the expression of NLRP3 inflammasome-associated proteins through its impact on the NF-κB pathway. Overall, our in vitro and in vivo investigations on efficacies and molecular-level mechanisms demonstrate the ability of DAPPD to regulate microglial function, suppress neuroinflammation, foster cerebral Aß clearance, and attenuate cognitive deficits in AD transgenic mouse models. Discovery of such antineuroinflammatory compounds signifies the potential in discovering effective therapeutic molecules against AD-associated neurodegeneration.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Antiinflamatorios/farmacología , Cognición/efectos de los fármacos , Microglía/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Fagocitosis/efectos de los fármacos , Fenilendiaminas/farmacología , Enfermedad de Alzheimer/psicología , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animales , Antiinflamatorios/uso terapéutico , Evaluación Preclínica de Medicamentos , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Inflamasomas/efectos de los fármacos , Inflamasomas/genética , Aprendizaje por Laberinto , Ratones , Ratones Transgénicos , Microglía/fisiología , Estructura Molecular , Proteínas del Tejido Nervioso/biosíntesis , Proteínas del Tejido Nervioso/genética , Fármacos Neuroprotectores/uso terapéutico , Fragmentos de Péptidos/genética , Fenilendiaminas/química , Fenilendiaminas/uso terapéutico , Presenilina-1/genética , Memoria Espacial/efectos de los fármacos
3.
Biochem Biophys Res Commun ; 569: 29-34, 2021 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-34225077

RESUMEN

Xenopus laevis is highly suitable as a toxicology animal model owing to its advantages in embryogenesis research. For toxicological studies, a large number of embryos must be handled simultaneously because they very rapidly develop into the target stages within a short period of time. To efficiently handle the embryos, a convenient embryo housing device is essential for fast and reliable assessment and statistical evaluation of malformation caused by toxicants. Here, we suggest 3D fabrication of single-egg trapping devices in which Xenopus eggs are fertilized in vitro, and the embryos are cultured. We used manual pipetting to insert the Xenopus eggs inside the trapping sites of the chip. By introducing a liquid circulating system, we connected a sperm-mixed solution with the chip to induce in vitro fertilization of the eggs. After the eggs were fertilized, we observed embryo development involving the formation of egg cleavage, blastula, gastrula, and tadpole. After the tadpoles grew inside the chip, we saved their lives by enabling their escape from the chip through reverse flow of the culture medium. The Xenopus chip can serve as an incubator to induce fertilization and monitor normal and abnormal development of the Xenopus from egg to tadpole.


Asunto(s)
Embrión no Mamífero/embriología , Fertilización In Vitro/métodos , Oocitos/citología , Xenopus laevis/embriología , Animales , Blástula/citología , Blástula/embriología , Blástula/fisiología , División Celular/fisiología , Embrión no Mamífero/citología , Embrión no Mamífero/fisiología , Femenino , Fertilización In Vitro/instrumentación , Gástrula/citología , Gástrula/embriología , Gástrula/fisiología , Larva/citología , Larva/crecimiento & desarrollo , Larva/fisiología , Locomoción/fisiología , Masculino , Oocitos/fisiología , Xenopus laevis/fisiología
4.
Mol Pharm ; 18(1): 101-112, 2021 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-33241681

RESUMEN

We report a prodrug, Glu-DAPPD, to overcome the shortcomings of an anti-neuroinflammatory molecule, N,N'-diacetyl-p-phenylenediamine (DAPPD), in biological applicability for potential therapeutic applications. We suspect that Glu-DAPPD can release DAPPD through endogenous enzymatic bioconversion. Consequently, Glu-DAPPD exhibits in vivo efficacies in alleviating neuroinflammation, reducing amyloid-ß aggregate accumulation, and improving cognitive function in Alzheimer's disease transgenic mice. Our studies demonstrate that the prodrug approach is suitable and effective toward developing drug candidates against neurodegeneration.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Cognición/efectos de los fármacos , Disfunción Cognitiva/tratamiento farmacológico , Inflamación/tratamiento farmacológico , Neuronas/efectos de los fármacos , Profármacos/farmacología , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Animales , Línea Celular Tumoral , Disfunción Cognitiva/metabolismo , Modelos Animales de Enfermedad , Humanos , Inflamación/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Microglía/efectos de los fármacos , Microglía/metabolismo , Neuronas/metabolismo , Fenilendiaminas/farmacología
5.
J Med Genet ; 57(2): 124-131, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31649052

RESUMEN

BACKGROUND: Ambroxol (ABX) has been suggested as an augmentative pharmacological agent for neuronopathic Gaucher disease (nGD). This study assessed the long-term safety and efficacy of combined therapy with high-dose ABX and enzyme replacement therapy (ERT) in nGD. METHODS: ABX+ERT therapy was administered for 4.5 years in four patients with nGD. ABX was initiated at a dose of 1.5 mg/kg/day, and the dose was escalated up to 27 mg/kg/day. The target plasma level was 10 µmol/L or less. The changes in glucocerebrosidase activity, biochemical, safety and neurocognitive findings were assessed. RESULTS: Enhanced residual GCcase activity was observed in all patients, as evidenced in both in vitro and in vivo studies. During the first 2 years of study with ABX (up to 21 mg/kg/day), mean seizure frequencies and neurocognitive function worsened. After ABX dosage was increased up to 27 mg/kg/day of ABX, its trough plasma concentration was 3.2-8.8 µmol/L. Drug-to-drug interaction, especially with antiepileptic drug significantly affected the pharmacokinetic parameters of ABX. Importantly, at 27 mg/kg/day of ABX, the seizure frequencies markedly decreased from the baseline, and the neurocognitive function was improved. In addition, Lyso-Gb1, a biomarker for the severity and progression of GD, was normalised in all patients. High-dose ABX was well-tolerated with no severe adverse events. CONCLUSIONS: Long-term treatment with high-dose ABX+ERT was safe and might help to arrest the progression of the neurological manifestations in GD.


Asunto(s)
Ambroxol/administración & dosificación , Terapia de Reemplazo Enzimático , Epilepsias Mioclónicas/tratamiento farmacológico , Enfermedad de Gaucher/tratamiento farmacológico , Adolescente , Biomarcadores/sangre , Niño , Relación Dosis-Respuesta a Droga , Epilepsias Mioclónicas/sangre , Epilepsias Mioclónicas/patología , Femenino , Enfermedad de Gaucher/sangre , Enfermedad de Gaucher/patología , Glucosilceramidasa/sangre , Humanos , Masculino
6.
Int J Mol Sci ; 22(14)2021 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-34298977

RESUMEN

For decades, lipids were confined to the field of structural biology and energetics as they were considered only structural constituents of cellular membranes and efficient sources of energy production. However, with advances in our understanding in lipidomics and improvements in the technological approaches, astounding discoveries have been made in exploring the role of lipids as signaling molecules, termed bioactive lipids. Among these bioactive lipids, sphingolipids have emerged as distinctive mediators of various cellular processes, ranging from cell growth and proliferation to cellular apoptosis, executing immune responses to regulating inflammation. Recent studies have made it clear that sphingolipids, their metabolic intermediates (ceramide, sphingosine-1-phosphate, and N-acetyl sphingosine), and enzyme systems (cyclooxygenases, sphingosine kinases, and sphingomyelinase) harbor diverse yet interconnected signaling pathways in the central nervous system (CNS), orchestrate CNS physiological processes, and participate in a plethora of neuroinflammatory and neurodegenerative disorders. Considering the unequivocal importance of sphingolipids in CNS, we review the recent discoveries detailing the major enzymes involved in sphingolipid metabolism (particularly sphingosine kinase 1), novel metabolic intermediates (N-acetyl sphingosine), and their complex interactions in CNS physiology, disruption of their functionality in neurodegenerative disorders, and therapeutic strategies targeting sphingolipids for improved drug approaches.


Asunto(s)
Sistema Nervioso Central/fisiopatología , Inflamación/fisiopatología , Lípidos de la Membrana/fisiología , Modelos Biológicos , Degeneración Nerviosa/fisiopatología , Enfermedades Neurodegenerativas/fisiopatología , Esfingolípidos/fisiología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/fisiopatología , Ceramidas/fisiología , Eicosanoides/fisiología , Predicción , Homeostasis , Humanos , Inflamación/patología , Lipooxigenasa/fisiología , Lisofosfolípidos/fisiología , Degeneración Nerviosa/patología , Enfermedades Neurodegenerativas/patología , Neuroglía/metabolismo , Neuronas/metabolismo , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/fisiopatología , Fosfotransferasas (Aceptor de Grupo Alcohol)/fisiología , Prostaglandina-Endoperóxido Sintasas/fisiología , Esfingosina/análogos & derivados , Esfingosina/fisiología
7.
Mol Ther ; 27(8): 1507-1526, 2019 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-31138511

RESUMEN

Gliosis in Niemann-Pick type C (NP-C) disease is characterized by marked changes in microglia and astrocytes. However, the gliosis onset and progression in NP-C has not been systematically studied, nor has the mechanism underlying this finding. Here, we found early gliosis in the subventricular zone (SVZ) of NP-C mice. Neural progenitor damage by Npc1 mutation suppressed vascular endothelial growth factor (VEGF) expression and further induced microglia activation followed by astrogliosis. Interestingly, excessive astrogliosis in the SVZ induced neural progenitor retention and/or migration into thalamus via astrocyte-derived VEGF, resulting in acceleration of thalamic and cortical gliosis through thalamo-cortical pathways. Transplantation of VEGF-overexpressing neural stem cells into the SVZ improved whole-brain pathology of NP-C mice. Overall, our data provide a new pathological perspective on NP-C neural pathology, revealing abnormalities in the subventricular-thalamo-cortical circuit of NP-C mouse brain and highlighting the importance of the SVZ microenvironment as a therapeutic target for NP-C disease.


Asunto(s)
Corteza Cerebral/metabolismo , Ventrículos Laterales/metabolismo , Enfermedad de Niemann-Pick Tipo C/metabolismo , Transducción de Señal , Tálamo/metabolismo , Animales , Astrocitos/metabolismo , Biomarcadores , Movimiento Celular , Modelos Animales de Enfermedad , Gliosis/etiología , Gliosis/metabolismo , Gliosis/patología , Ratones , Microglía/metabolismo , Células-Madre Neurales/metabolismo , Enfermedad de Niemann-Pick Tipo C/etiología , Enfermedad de Niemann-Pick Tipo C/patología , Enfermedad de Niemann-Pick Tipo C/terapia , Factor A de Crecimiento Endotelial Vascular/metabolismo
8.
EMBO J ; 34(12): 1648-60, 2015 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-25916827

RESUMEN

Many reports have revealed the importance of the sympathetic nervous system (SNS) in the control of the bone marrow environment. However, the specific role of neuropeptide Y (NPY) in this process has not been systematically studied. Here we show that NPY-deficient mice have significantly reduced hematopoietic stem cell (HSC) numbers and impaired regeneration in bone marrow due to apoptotic destruction of SNS fibers and/or endothelial cells. Furthermore, pharmacological elevation of NPY prevented bone marrow impairments in a mouse model of chemotherapy-induced SNS injury, while NPY injection into conditional knockout mice lacking the Y1 receptor in macrophages did not relieve bone marrow dysfunction. These results indicate that NPY promotes neuroprotection and restores bone marrow dysfunction from chemotherapy-induced SNS injury through the Y1 receptor in macrophages. They also reveal a new role of NPY as a regulator of the bone marrow microenvironment and highlight the potential therapeutic value of this neuropeptide.


Asunto(s)
Células de la Médula Ósea/metabolismo , Médula Ósea/fisiología , Microambiente Celular/fisiología , Células Madre Hematopoyéticas/fisiología , Fibras Nerviosas Mielínicas/metabolismo , Neuropéptido Y/metabolismo , Análisis de Varianza , Animales , Apoptosis/fisiología , Células Endoteliales/fisiología , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Células Madre Hematopoyéticas/metabolismo , Ratones , Ratones Noqueados , Neuropéptido Y/deficiencia , Sistema Nervioso Simpático/citología
9.
Aesthetic Plast Surg ; 43(2): 498-513, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30635686

RESUMEN

BACKGROUND: To overcome unpredictable fat graft resorption, cell-assisted lipotransfer using stromal vascular fraction (SVF) has been introduced. However, its effect on cancer growth stimulation and its oncological safety are debatable. We investigated the effect of SVF on adjacent breast cancer and transplanted fat in a mouse model. METHODS: A breast cancer xenograft model was constructed by injecting 2 × 106 MDA-MB-231-luc breast cancer cells into the right lower back of 40 NOD/SCID mice. Two weeks later, cancer size was sorted according to signal density using an in vivo optical imaging system, and 36 mice were included. Human fat was extracted from the abdomen, and SVFs were isolated using a component isolator. The mice were divided into four groups: A, controls; B, injected with 30 µl SVF; C, injected with 0.5 ml fat and 30 µl saline; group D, injected with 0.5 ml fat and 30 µl SVF. Magnetic resonance imaging and three-dimensional micro-computed tomography volumetric analysis were performed at 4 and 8 weeks. RESULTS: Tumor volume was 43.6, 42.3, 48.7, and 42.4 mm3 at the initial time point and 6780, 5940, 6080, and 5570 mm3 at 8 weeks in groups A, B, C, and D, respectively. Fat graft survival volume after 8 weeks was 49.32% and 62.03% in groups C and D, respectively. At 2-month follow-up after fat grafting in the xenograft model, SVF injection showed an increased fat survival rate and did not increase the adjacent tumor growth significantly. CONCLUSION: Fat grafting with SVF yields satisfactory outcome in patients who undergo breast reconstruction surgery. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.


Asunto(s)
Tejido Adiposo/trasplante , Neoplasias de la Mama/patología , Animales , Modelos Animales de Enfermedad , Femenino , Humanos , Ratones , Ratones Endogámicos NOD , Ratones SCID
10.
Neurochem Res ; 43(12): 2362-2371, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30327995

RESUMEN

Neuroinflammation is an important pathological feature in neurodegenerative diseases. Accumulating evidence has suggested that neuroinflammation is mainly aggravated by activated microglia, which are macrophage like cells in the central nervous system. Therefore, the inhibition of microglial activation may be considered for treating neuroinflammatory diseases. p38 mitogen-activated protein kinase (MAPK) has been identified as a crucial enzyme with inflammatory roles in several immune cells, and its activation also relates to neuroinflammation. Considering the proinflammatory roles of p38 MAPK, its inhibitors can be potential therapeutic agents for neurodegenerative diseases relating to neuroinflammation initiated by microglia activation. This study was designed to evaluate whether NJK14047, a recently identified novel and selective p38 MAPK inhibitor, could modulate microglia-mediated neuroinflammation by utilizing lipopolysaccharide (LPS)-stimulated BV2 cells and an LPS-injected mice model. Our results showed that NJK14047 markedly reduced the production of nitric oxide and prostaglandin E2 by downregulating the expression of various proinflammatory mediators such as nitric oxide synthase, cyclooxygenase-2, tumor necrosis factor-α and interleukin-1ß in LPS-induced BV2 microglia. Moreover, NJK14047 significantly reduced microglial activation in the brains of LPS-injected mice. Overall, these results suggest that NJK14047 significantly reduces neuroinflammation in cellular/vivo model and would be a therapeutic candidate for various neuroinflammatory diseases.


Asunto(s)
Mediadores de Inflamación/metabolismo , Lipopolisacáridos/toxicidad , Microglía/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Animales , Línea Celular , Relación Dosis-Respuesta a Droga , Imidazoles/farmacología , Imidazoles/uso terapéutico , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Mediadores de Inflamación/antagonistas & inhibidores , Masculino , Ratones , Ratones Endogámicos C57BL , Microglía/efectos de los fármacos , Inhibidores de Proteínas Quinasas/uso terapéutico , Piridinas/farmacología , Piridinas/uso terapéutico
11.
J Pharmacol Sci ; 137(2): 195-201, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29970291

RESUMEN

Inflammatory processes in the central nervous system are feature among biological reactions to harmful stimuli such as pathogens and damaged cells. In resting conditions, microglia are involved in immune surveillance and brain homeostasis. However, the activation of abnormal microglia can be detrimental to neurons, even resulting in neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease and Huntington's disease. Therefore, normalization of microglial activation is considered a promising strategy for developing drugs that can treat or prevent inflammation-related brain diseases. In the present study, we investigated the effects of piperlongumine, an active component of Piper longum, on lipopolysaccharide (LPS)-induced neuroinflammation using BV2 microglial cells. We found that piperlongumine significantly inhibited the production of nitric oxide and prostaglandin E2 induced by LPS. Piperlongumine also reduced the expression of inducible nitric oxide synthase and cyclooxygenase-2 as well as proinflammatory cytokines such as tumor necrosis factor-α and interleukin-6. Piperlongumine exerted its anti-neuroinflammatory effects by suppressing the nuclear factor kappa B signaling pathway. These findings suggest that piperlongumine could be a candidate agent for the treatment of inflammation-related neurodegenerative diseases.


Asunto(s)
Antiinflamatorios , Dioxolanos/farmacología , Lipopolisacáridos/efectos adversos , Microglía/metabolismo , FN-kappa B/metabolismo , Transducción de Señal/efectos de los fármacos , Animales , Ciclooxigenasa 2/metabolismo , Depresión Química , Dinoprostona/metabolismo , Mediadores de Inflamación/metabolismo , Interleucina-6/metabolismo , Ratones , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Piper/química , Factor de Necrosis Tumoral alfa/metabolismo
12.
Stem Cells ; 34(8): 2145-56, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27090492

RESUMEN

Hematopoietic stem/progenitor cell (HSPC) mobilization is an essential homeostatic process regulated by the interaction of cellular and molecular components in bone marrow niches. It has been shown by others that neurotransmitters released from the sympathetic nervous system regulate HSPC egress from bone marrow to peripheral blood. In this study, we investigate the functional role of neuropeptide Y (NPY) on this process. NPY deficient mice had significantly impaired HSPC mobilization due to increased expression of HSPC maintenance factors by reduction of matrix metalloproteinase-9 (MMP-9) activity in bone marrow. Pharmacological or endogenous elevation of NPY led to decrease of HSPC maintenance factors expression by activating MMP-9 in osteoblasts, resulting in HSPC mobilization. Mice in which the Y1 receptor was deleted in osteoblasts did not exhibit HSPC mobilization by NPY. Furthermore, NPY treatment in ovariectomized mice caused reduction of bone loss due to HSPC mobilization. These results suggest a new role of NPY on HSPC mobilization, as well as the potential therapeutic application of this neuropeptide for stem cell-based therapy. Stem Cells 2016;34:2145-2156.


Asunto(s)
Movilización de Célula Madre Hematopoyética , Metaloproteinasa 9 de la Matriz/metabolismo , Neuropéptido Y/metabolismo , Osteoblastos/metabolismo , Receptores de Neuropéptido Y/metabolismo , Animales , Huesos/metabolismo , Quimiotaxis , Femenino , Homeostasis , Ratones Endogámicos C57BL , Neuropéptido Y/deficiencia , Osteoblastos/citología , Osteoblastos/enzimología , Receptores CXCR4/metabolismo
13.
Opt Express ; 24(5): 5411-5422, 2016 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-29092364

RESUMEN

In this study, an online refocusing algorithm is proposed for a satellite camera performing an Earth observation mission. Satellite cameras are vulnerable to misalignment in orbit because of their severe launching environments and the thermal vacuum environment in space. The proposed online refocusing algorithm is able to guarantee high quality images by aligning the satellite camera in real time. This alignment is achieved by precisely adjusting the movement mechanism of the secondary mirror (M2) and the focal plane. The target optical system used in this study was originally designed for the purposes of algorithm development. The system uses a Schmidt-Cassegrain-type satellite camera with a 200-mm diameter primary mirror (M1). The ground sampling distance (GSD) is 3.8 m from an altitude of 700 km. A fourth-order equation model is derived for the modulation transfer function (MTF) variation tendency for M2 de-spacing. Following this, the proposed online refocusing algorithm for the target optical system is developed. The algorithm is able to assess the de-space position from the MTF measurements using stellar sources. It is determined from the simulation that any misaligned satellite camera can be refocused within a ± 0.5µm M2 de-space error by applying the proposed refocusing algorithm in real time.

14.
J Korean Med Sci ; 31(7): 1168-72, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27366019

RESUMEN

Niemann-Pick disease, type C (NP-C), is caused by NPC1 or NPC2 gene mutations. Progressive neurological, psychiatric, and visceral symptoms are characteristic. Here, we present cases of a brother (Case 1) and sister (Case 2) in their mid-20s with gait disturbance and psychosis. For the Case 1, neurological examination revealed dystonia, ataxia, vertical supranuclear-gaze palsy (VSGP), and global cognitive impairment. Case 2 showed milder, but similar symptoms, with cortical atrophy. Abdominal computed tomography showed hepatosplenomegaly in both cases. NPC1 gene sequencing revealed compound heterozygote for exon 9 (c.1552C>T [R518W]) and exon 18 (c.2780C>T [A927V]). Filipin-staining tests were also positive. When a young patient with ataxia or dystonia shows VSGP, NP-C should be considered.


Asunto(s)
Enfermedad de Niemann-Pick Tipo C/diagnóstico , Abdomen/diagnóstico por imagen , Pueblo Asiatico/genética , Proteínas Portadoras/genética , Análisis Mutacional de ADN , Exones , Femenino , Trastornos Neurológicos de la Marcha/etiología , Humanos , Péptidos y Proteínas de Señalización Intracelular , Masculino , Glicoproteínas de Membrana/genética , Proteína Niemann-Pick C1 , Enfermedad de Niemann-Pick Tipo C/genética , Trastornos Psicóticos/etiología , República de Corea , Hermanos , Tomografía Computarizada por Rayos X , Adulto Joven
15.
Angew Chem Int Ed Engl ; 55(4): 1318-23, 2016 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-26663348

RESUMEN

We demonstrate the synthesis of a microporous covalent-network membrane derived from co-continuous blends of a porogenic urea network and a polyimide (PI). We show that the urea networks in the PI matrix may be thermally rearranged while selectively expelling small molecular fragments, thereby forming a new network bearing reticular microporous molecular pathways. The porous structures enable reverse-selective gas separation, efficiently blocking carbon dioxide to which most polymeric membranes exhibit selective permeability. The proposed method for fabricating microporous organic membranes with highly tunable porosities using a variety of chemical structures and processing parameters is facile and shows promise for the creation of new membrane-based molecular-separation techniques.

16.
Angew Chem Int Ed Engl ; 55(38): 11495-8, 2016 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-27513827

RESUMEN

The preparation of bicontinuous nanoporous covalent frameworks, which are promising for caging active enzymes, is demonstrated. The frameworks have three- dimensionally continuous, hydrophilic pores with widths varying between 5 and 30 nm. Enzymes were infiltrated into the bicontinuous pore by applying a pressured enzyme solution. The new materials and methods allowed the amount of caged proteins to be controlled precisely. The resulting enzyme-loaded framework films could be recycled many times with nearly no loss of catalytic activity. Entropic trapping of proteins by a bicontinuous pore with the right size distribution is an unprecedented strategy toward facile in vitro utilization of biocatalysts.


Asunto(s)
Enzimas/química , Nanoporos , Biocatálisis , Enzimas/metabolismo , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Interacciones Hidrofóbicas e Hidrofílicas , Lipasa/química , Lipasa/metabolismo , Ácido Oléico/metabolismo , Polietilenglicoles/química , Factores de Tiempo
17.
Anal Biochem ; 469: 65-70, 2015 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-25277814

RESUMEN

The quantification of apoptotic cells is an integral component of many cell-based assays in biological studies. However, current methods for quantifying apoptotic cells using conventional random cultures have shown great limitations, especially for the quantification of primary neurons. Randomly distributed neurons under primary culture conditions can lead to biased estimates, and vastly different estimates of cell numbers can be produced within the same experiment. In this study, we developed a simple, accurate, and reliable technique for quantifying apoptotic neurons by means of micropatterned cell cultures. A polydimethylsiloxane (PDMS) microstencil was used as a physical mask for micropatterning cell cultures, and primary granular neurons (GNs) were successfully cultured within the micropattern-confined regions and homogeneously distributed over the entire field of each pattern. As compared with the conventional method based on random cultures, the micropatterned culture method allowed for highly reproducible quantification of apoptotic cells. These results were also confirmed by using GNs derived from mice with neurodegeneration. We hope that this micropatterning method based on the use of a PDMS microstencil can overcome the technical obstacles existing in current biological studies and will serve as a powerful tool for facilitating the study of apoptosis-involved diseases.


Asunto(s)
Apoptosis , Neuronas/citología , Animales , Células de la Médula Ósea/citología , Células Cultivadas , Dimetilpolisiloxanos/química , Células Madre Mesenquimatosas/citología , Ratones , Ratones Endogámicos BALB C , Enfermedades Neurodegenerativas/metabolismo , Enfermedades Neurodegenerativas/patología , Neuronas/metabolismo
18.
BJU Int ; 114(5): 770-83, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24841807

RESUMEN

OBJECTIVE: To investigate whether a triple combination of early-differentiated cells derived from human amniotic fluid stem cells (hAFSCs) would show synergistic effects in urethral sphincter regeneration. MATERIALS AND METHODS: We early-differentiated hAFSCs into muscle, neuron and endothelial progenitor cells and then injected them into the urethral sphincter region of pudendal neurectomized ICR mice, as single-cell, double-cell or triple-cell combinations. Urodynamic studies and histological, immunohistochemical and molecular analyses were performed. RESULTS: Urodynamic study showed significantly improved leak point pressure in the triple-cell-combination group compared with the single-cell- or double-cell-combination groups. These functional results were confirmed by histological and immunohistochemical analyses, as evidenced by the formation of new striated muscle fibres and neuromuscular junctions at the cell injection site. Molecular analysis showed higher target marker expression in the retrieved urethral tissue of the triple-cell-combination group. The injection of early-differentiated hAFSCs suppressed in vivo host CD8 lymphocyte aggregations and did not form teratoma. The nanoparticle-labelled early-differentiated hAFSCs could be tracked in vivo with optical imaging for up to 14 days after injection. CONCLUSION: Our novel concept of triple-combined early-differentiated cell therapy for the damaged sphincter may provide a viable option for incontinence treatment.


Asunto(s)
Líquido Amniótico/citología , Trasplante de Células Madre/métodos , Células Madre/citología , Vejiga Urinaria/citología , Incontinencia Urinaria/terapia , Animales , Diferenciación Celular/fisiología , Rastreo Celular , Femenino , Humanos , Ratones , Ratones Endogámicos ICR
19.
Exp Mol Med ; 56(2): 301-310, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38337058

RESUMEN

Over the past decade, numerous studies have highlighted the importance of acid sphingomyelinase (ASM) in disease treatment in humans. This enzyme functions primarily to generate ceramide, maintain the cellular membrane, and regulate cellular function. However, in the blood and brain of patients with neurological disorders, including major depression, ischemic stroke, amyotrophic lateral sclerosis, multiple sclerosis, and Alzheimer's disease (AD), elevated ASM levels significantly suggest disease onset or progression. In these diseases, increased ASM is profoundly involved in neuronal death, abnormal autophagy, neuroinflammation, blood-brain barrier disruption, hippocampal neurogenesis loss, and immune cell dysfunction. Moreover, genetic and pharmacological inhibition of ASM can prevent or ameliorate various diseases. The therapeutic effects of ASM inhibition have prompted the urgent need to develop ASM inhibitors, and several ASM inhibitors have been identified. In this review, we summarize the current knowledge on the critical roles and mechanisms of ASM in brain cells and blood that are associated with different neuropathological features, especially those observed in AD. Furthermore, we elucidate the potential possibility and limitations of existing ASM-targeting drugs according to experimental studies in neurological disorder mouse models.


Asunto(s)
Enfermedad de Alzheimer , Esclerosis Múltiple , Enfermedades del Sistema Nervioso , Animales , Humanos , Ratones , Enfermedad de Alzheimer/tratamiento farmacológico , Encéfalo , Esfingomielina Fosfodiesterasa/genética
20.
Research (Wash D C) ; 7: 0365, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38654733

RESUMEN

Neutrophils are primed for neutrophil extracellular trap (NET) formation during diabetes, and excessive NET formation from primed neutrophils compromises wound healing in patients with diabetes. Here, we demonstrate that trained immunity mediates diabetes-induced NET priming in neutrophils. Under diabetic conditions, neutrophils exhibit robust metabolic reprogramming comprising enhanced glycolysis via the pentose phosphate pathway and fatty acid oxidation, which result in the accumulation of acetyl-coenzyme A. Adenosine 5'-triphosphate-citrate lyase-mediated accumulation of acetyl-coenzyme A and histone acetyltransferases further induce the acetylation of lysine residues on histone 3 (AcH3K9, AcH3K14, and AcH3K27) and histone 4 (AcH4K8). The pharmacological inhibition of adenosine 5'-triphosphate-citrate lyase and histone acetyltransferases completely inhibited high-glucose-induced NET priming. The trained immunity of neutrophils was further confirmed in neutrophils isolated from patients with diabetes. Our findings suggest that trained immunity mediates functional changes in neutrophils in diabetic environments, and targeting neutrophil-trained immunity may be a potential therapeutic target for controlling inflammatory complications of diabetes.

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