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1.
Geophys Res Lett ; 48(20): e2021GL093796, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34924636

RESUMEN

Aerosols emitted in densely populated and industrialized Indo-Gangetic Plain, one of the most polluted regions in the world, modulate regional climate, monsoon, and Himalayan glacier retreat. Thus, this region is important for understanding aerosol perturbations and their resulting impacts on atmospheric changes during COVID-19 lockdown period, a natural experimental condition created by the pandemic. By analyzing 5 years (2016-2020) data of aerosols and performing a radiative transfer calculation, we found that columnar and near-surface aerosol loadings decreased, leading to reductions in radiative cooling at the surface and top of the atmosphere and atmospheric warming during lockdown period. Further, satellite data analyses showed increases in cloud optical thickness and cloud-particle effective radius and decrease in lower tropospheric air temperature during lockdown period. These results indicate critical influences of COVID-19 lockdown on regional climate and water cycle over Indo-Gangetic Plain, emphasizing need for further studies from modeling perspectives.

2.
Eur J Vasc Endovasc Surg ; 40(5): 657-63, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20817502

RESUMEN

BACKGROUND: The lipid metabolism of varicose veins (VVs) remains unknown. To elucidate the pathogenesis of VV, we utilized the novel technique of imaging mass spectrometry (IMS). MATERIALS AND METHODS: We obtained VV tissues from 10 limbs of 10 VV patients who underwent great saphenous vein stripping. As control vein samples, we harvested segmental vein tissues from 6 limbs of 6 patients with peripheral artery occlusive disease who underwent infra-inguinal bypass with reversed saphenous vein grafting. To identify the localisation of lipid molecules in the VV tissues, we performed matrix-assisted laser desorption/ionization IMS (MALDI-IMS). We also performed MS/MS analyses to identify the structure of each molecule. RESULTS: We obtained mass spectra directly from control vein tissues and VV tissues and found a unique localisation of lipid molecules in the VV tissues. We localised lysophosphatidylcholine (LPC) (1-acyl 16:0), phosphatidylcholine (PC) (1-acyl 36:4) and sphingomyelin (SM) (d18:1/16:0) at the site of the VV valve. CONCLUSION: MALDI-IMS revealed the distribution of various lipid molecules in normal veins and VVs both. Accumulation of LPC (1-acyl 16:0), PC (1-acyl 36:4) and SM (d18:1/16:0) in the VV tissues suggested that inflammation associated with abnormal lipid metabolism may contribute to the development of VV.


Asunto(s)
Lípidos , Vena Safena/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Várices/metabolismo , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Metabolismo de los Lípidos/fisiología , Masculino , Espectrometría de Masas , Persona de Mediana Edad , Vena Safena/fisiopatología , Várices/fisiopatología
3.
Technol Health Care ; 17(2): 121-31, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19564677

RESUMEN

An effective way for preventing injuries and diseases among the elderly is to monitor their daily lives. In this regard, we propose the use of a "Hyper Hospital Network", which is an information support system for elderly people and patients. In the current study, we developed a wearable system for monitoring electromyography (EMG) and acceleration using the Hyper Hospital Network plan. The current system is an upgraded version of our previous system for gait analysis (Yoshida et al. [13], Telemedicine and e-Health 13 703-714), and lets us monitor decreases in exercise and the presence of a hemiplegic gait more accurately. To clarify the capabilities and reliability of the system, we performed three experimental evaluations: one to verify the performance of the wearable system, a second to detect a hemiplegic gait, and a third to monitor EMG and accelerations simultaneously. Our system successfully detected a lack of exercise by monitoring the iEMG in healthy volunteers. Moreover, by using EMG and acceleration signals simultaneously, the reliability of the Hampering Index (HI) for detecting hemiplegia walking was improved significantly. The present study provides useful knowledge for the development of a wearable computer designed to monitor the physical conditions of older persons and patients.


Asunto(s)
Ejercicio Físico , Marcha , Internet , Monitoreo Ambulatorio/instrumentación , Monitoreo Ambulatorio/métodos , Electromiografía , Humanos , Evaluación de la Tecnología Biomédica
4.
Phytopathology ; 98(9): 1038-44, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18943742

RESUMEN

To test the hypothesis that silicon (Si) confers resistance against appressorial penetration of the rice blast fungus, the proportion of appressorial penetration into the leaf epidermis to total appressoria formed was compared among rice plants amended with various rates of silica gel to those plants nonamended. The amounts of Si in the youngest leaves were consistent with the amounts of silica gel applied to the rice plants. Relative Si levels on the adaxial surface of leaves as detected by energy dispersive X-ray analysis also increased with the amounts of silica gel applied. Based on light microscopic observation of the adaxial surface of rice leaves, the proportion of appressorial penetration was reduced by increasing amounts of silica gel applied and increased with the length of period after spray inoculation. Consequently, these results strongly support the hypothesis and suggest that Si in the leaf epidermis may confer resistance against appressorial penetration. Meanwhile, the number of lesions per leaf also decreased with the amount of Si applied, while only a certain part of penetrated appressoria could become sporulating susceptible lesions. This suggests that Si also confers physiological resistance against blast infection after the penetration.


Asunto(s)
Oryza/microbiología , Enfermedades de las Plantas/microbiología , Silicio/uso terapéutico , Hongos/efectos de los fármacos , Hongos/patogenicidad , Microscopía Electrónica de Rastreo , Oryza/efectos de los fármacos , Oryza/crecimiento & desarrollo , Oryza/ultraestructura , Fotosíntesis/efectos de los fármacos , Hojas de la Planta/microbiología , Hojas de la Planta/ultraestructura
5.
J Geophys Res Atmos ; 122(20): 11022-11044, 2017 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-32818127

RESUMEN

We developed a method for classifying hydrometeor particle types, including cloud and precipitation phase and ice crystal habit, by a synergistic use of CloudSat/Cloud Profiling Radar (CPR) and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO)/Cloud-Aerosol LIdar with Orthogonal Polarization (CALIOP). We investigated how the cloud phase and ice crystal habit characterized by CALIOP globally relate with radar reflectivity and temperature. The global relationship thus identified was employed to develop an algorithm for hydrometeor type classification with CPR alone. The CPR-based type classification was then combined with CALIPSO-based type characterization to give CPR-CALIOP synergy classification. A unique aspect of this algorithm is to exploit and combine the lidar's sensitivity to thin ice clouds and the radar's ability to penetrate light precipitation to offer more complete picture of vertically resolved hydrometeor type classification than has been provided by previous studies. Given the complementary nature of radar and lidar detections of hydrometeors, our algorithm delivers thirteen hydrometeor types: warm water, supercooled water, randomly-oriented ice crystal (3D-ice), horizontally-oriented plate (2D-plate), 3D-ice+2D-plate, liquid drizzle, mixed-phase drizzle, rain, snow, mixed-phase cloud, water+liquid drizzle, water+rain and unknown. The global statistics of three-dimensional occurrence frequency of each hydrometeor type revealed that 3D-ice contributes the most to the total cloud occurrence frequency (53.8%), followed by supercooled water (14.3%), 2D-plate (9.2%), rain (5.9%), warm water (5.7%), snow (4.8%), mixed-phase drizzle (2.3%), and the remaining types (4.0%). This hydrometeor type classification provides useful observation-based information for climate model diagnostics in representation of cloud phase and their microphysical characteristics.

6.
Neuroscience ; 322: 66-77, 2016 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-26873001

RESUMEN

BACKGROUND AND PURPOSE: The initial steps in the cascade leading to cell death are still unknown because of the limitations of the existing methodology, strategy, and modalities used. METHODS: Imaging mass spectrometry (IMS) was used to measure dynamic molecular changes of phosphatidylcholine (PC) species in the rat hippocampus after transient global ischemia (TGI) for 6min. Fresh frozen sections were obtained after euthanizing the rats on Days 1, 2, 4, 7, 10, 14, and 21. Histopathology and IMS of adjacent sections compared morphological and molecular changes, respectively. RESULTS: Histopathological changes were absent immediately after TGI (at Day 1, superacute phase). At Days 2-21 after TGI (from subacute to chronic phases), histopathology revealed neuronal death associated with gliosis, inflammation, and accumulation of activated microglia in CA1. IMS detected significant molecular changes after TGI in the same CA1 domain: increase of PC (diacyl-16:0/22:6) in the superacute phase and increase of PC (diacyl-16:0/18:1) in the subacute to chronic phases. CONCLUSIONS: Histopathology and IMS can provide comprehensive and complementary information on cell death mechanisms in the hippocampal CA1 after global ischemia. IMS provided novel data on molecular changes in phospholipids immediately after TGI. Increased level of PC (diacyl-16:0/22:6) in the pyramidal cell layer of hippocampal CA1 prior to the histopathological change may represent an early step in delayed neuronal death mechanisms.


Asunto(s)
Región CA1 Hipocampal/metabolismo , Ataque Isquémico Transitorio/metabolismo , Espectrometría de Masas/métodos , Fosfatidilcolinas/metabolismo , Enfermedad Aguda , Animales , Astrocitos/metabolismo , Astrocitos/patología , Región CA1 Hipocampal/patología , Muerte Celular/fisiología , Enfermedad Crónica , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Gliosis/metabolismo , Gliosis/patología , Inmunohistoquímica , Ataque Isquémico Transitorio/patología , Masculino , Microglía/metabolismo , Microglía/patología , Ratas Sprague-Dawley , Factores de Tiempo
7.
Technol Health Care ; 13(4): 293-300, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16055977

RESUMEN

We previously developed a network-based medical care support system called the Hyper Hospital, a computer network with an interface that is dedicated to patient care. In this study, we developed a wearable information system that is designed so that a caregiver can obtain information and control various support devices within the home-care environment. In our system, the wearable computer itself consists of a computer network built into a jacket. Each required function is implemented by a dedicated small computer connected to the in-jacket network. A new function may easily be added to the system by connecting additional computers. A network comprising such a set of single-function computers becomes a highly efficient information system when applied to health care support.


Asunto(s)
Cuidadores , Servicios de Atención de Salud a Domicilio , Microcomputadores , Interfaz Usuario-Computador , Procesamiento Automatizado de Datos/instrumentación , Humanos , Monitoreo Fisiológico
8.
Neuroscience ; 297: 127-36, 2015 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-25841322

RESUMEN

In this study, we analyzed the spatiotemporal alterations of phospholipid composition in the spinal cord of an amyotrophic lateral sclerosis (ALS) mouse model (G93A-mutated human superoxide dismutase 1 transgenic mice [SOD1(G93A) mice]) using imaging mass spectrometry (IMS), a powerful method to visualize spatial distributions of various types of molecules in situ. Using this technique, we deciphered the phospholipid distribution in the pre-symptomatic stage, early stage after disease onset, and terminal stages of disease in female SOD1(G93A) mouse spinal cords. These experiments revealed a significant decrease in levels of docosahexaenoic acid (DHA)-containing phosphatidylcholines (PCs), such as PC (diacyl-16:0/22:6), PC (diacyl-18:0/22:6), and PC (diacyl-18:1/22:6) in the L5 anterior horns of terminal stage (22-week-old) SOD1(G93A) mice. The reduction in PC (diacyl-16:0/22:6) level could be reflecting the loss of motor neurons themselves in the anterior horn of the spinal cord in ALS model mice. In contrast, other PCs, such as PC (diacyl-16:0/16:0), were observed specifically in the L5 dorsal horn gray matter, and their levels did not vary between ALS model mice and controls. Thus, our study showed a significant decrease in DHA-containing PCs, but not other PCs, in the terminal stage of ALS in model mice, which is likely to be a reflection of neuronal loss in the anterior horns of the spinal cords. Given its enrichment in dorsal sensory regions, the preservation of PC (diacyl-16:0/16:0) may be the result of spinal sensory neurons being unaffected in ALS. Taken together, these findings suggest that ALS spinal cords show significant alterations in PC metabolism only at the terminal stage of the disease, and that these changes are confined to specific anatomical regions and cell types.


Asunto(s)
Esclerosis Amiotrófica Lateral/metabolismo , Esclerosis Amiotrófica Lateral/patología , Células del Asta Anterior/metabolismo , Ácidos Docosahexaenoicos/metabolismo , Fosfatidilcolinas/metabolismo , Médula Espinal/patología , Análisis de Varianza , Animales , Modelos Animales de Enfermedad , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Superóxido Dismutasa/genética
9.
Neural Netw ; 14(10): 1419-29, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11771721

RESUMEN

In neural network regression problems, often referred to as additive noise models, NIC (Network Information Criterion) has been proposed as a general model selection criterion to determine the optimal network size with high generalization performance. Although NIC has been derived using asymptotic expansion, it has been pointed out that this technique cannot be applied under the assumption that a target function is in a family of assumed networks and the family is not minimal for representing the target true function, i.e. the overrealizable case, in which NIC reduces to the well-known AIC (Akaike Information Criterion) and others depending on a loss function. Because NIC is the unbiased estimator of generalization error based on training error, it is required to derive the expectations of errors for neural networks for such cases. This paper gives upper bounds of the expectations of training errors with respect to the distribution of training data, which we call the expected training error, for some types of networks under the squared error loss. In the overrealizable case, because the errors are determined by fitting properties of networks to noise components, including in data, the target set of data is taken to be a Gaussian noise sequence. For radial basis function networks and 3-layered neural networks with bell shaped activation function in the hidden layer, the expected training error is bounded above by sigma2* - 2nsigma2*logT/T, where sigma2* is the variance of noise, n is the number of basis functions or the number of hidden units and T is the number of data. Furthermore, for 3-layered neural networks with sigmoidal activation function in the hidden layer, we obtained the upper bound of sigma2* - O(log T/T) when n > 2. If the number of data is large enough, these bounds of the expected training error are smaller than sigma2* - N(n)sigma2*/T as evaluated in NIC, where N(n) is the number of all network parameters.


Asunto(s)
Redes Neurales de la Computación , Distribución Normal , Análisis de Varianza , Funciones de Verosimilitud , Análisis de Regresión , Proyectos de Investigación
10.
Intern Med ; 31(7): 955-9, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1450510

RESUMEN

A patient with allergic granulomatous angiitis accompanied by increases in serum interleukin-2 receptor (IL-2R) and interferon-alpha (IFN-alpha) levels is reported. Laboratory findings revealed leukocytosis with eosinophilia and increased serum IgE and IgG. The serum IL-2R and IFN-alpha were increased. The serum immune complex, interferon-beta, -gamma and complements remained at normal levels. The serum IgE, IgG, IL-2R and IFN-alpha correlated with disease activity. Immunofluorescent studies using frozen sections obtained from the dermal lesion showed no immunoglobulin or complement deposits on vascular walls. Measurements of serum IL-2R and IFN-alpha might be considered reliable serologic indicators of disease activity.


Asunto(s)
Síndrome de Churg-Strauss/sangre , Interferón-alfa/sangre , Receptores de Interleucina-2/análisis , Adulto , Síndrome de Churg-Strauss/diagnóstico , Síndrome de Churg-Strauss/tratamiento farmacológico , Proteínas del Sistema Complemento/análisis , Femenino , Humanos , Inmunoglobulinas/análisis , Prednisolona/uso terapéutico
11.
Hokkaido Igaku Zasshi ; 57(6): 688-95, 1982 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-6134659

RESUMEN

A comparative immunopathological and electron microscopic study of vasculitis and glomerulonephritis in autoimmune mice (B/W F1, SL/Ni, MRL/1) was performed. The pathogenesis of vasculitis in B/W F1 mice is due to the deposition of circulating murine leukemia virus (MuLV) gp70-immune complexes in the subendothelial space of vascular walls. Whereas, the vasculitis in SL/Ni mice is mediated by the budding of MuLV particles from vascular smooth muscle cells and the humoral immune response (Gross natural antibody) to virions and MuLV related cell surface antigens of vascular smooth muscle cells. The vasculitis in MRL/1 mice seems to be mediated mainly by the deposition of gp 70-immune complexes in vascular walls. However, the perivascular infiltration of thy1 . 2 antigen positive T-lymphocytes in an early stage of vasculitis suggests that the cellular immune response is, at least in part, important for the initiation of vasculitis in MRL/1 mice. The collective evidence suggests that several immunologic mechanisms are at works in the production of naturally occurring vasculitides in B/W F1, SL/Ni, and MRL/1 mice. The common pathogenesis of glomerulonephritis in B/W F1, SL/Ni and MRL/1 mice is the deposition of circulating gp70-immune complexes in the glomeruli. In addition, in the case of SL/Ni mice, glomerulonephritis is in some part initiated by local formations of the immune complex in the mesangium. The occurrence of vasculitis in MRL/1 mice is markedly accelerated by the treatment of methoxamine hydrochloride (Mexan), as was shown previously in SL/Ni mice.


Asunto(s)
Antígenos Virales/análisis , Glomerulonefritis/etiología , Virus de la Leucemia Murina/inmunología , Poliarteritis Nudosa/etiología , Animales , Glomerulonefritis/inmunología , Glomerulonefritis/patología , Inmunoglobulina G/análisis , Inmunoglobulina M/análisis , Ratones , Ratones Endogámicos NZB , Ratones Endogámicos , Poliarteritis Nudosa/inmunología , Poliarteritis Nudosa/patología , Arteria Renal/análisis
12.
Rinsho Hoshasen ; 34(12): 1497-500, 1989 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-2593298

RESUMEN

Three cases, two peritoneal lymphomatosis and one tuberculous peritonitis, which showed diffuse abdominal uptake of 67Ga-citrate, were reported. 67Ga scan should be indicated for patients suspected of malignancy or inflammation with a lack of localized symptoms and signs in the abdomen. 67Ga-citrate scan also can give notable information on the evaluation of therapeutic response in those patients.


Asunto(s)
Citratos , Radioisótopos de Galio , Linfoma no Hodgkin/diagnóstico por imagen , Neoplasias Peritoneales/diagnóstico por imagen , Peritonitis Tuberculosa/diagnóstico por imagen , Adulto , Ácido Cítrico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cintigrafía
13.
Neuroscience ; 269: 1-10, 2014 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-24657456

RESUMEN

The interleukin (IL)-6 pathway plays an important role in recovery after spinal cord injury (SCI). The anti-IL-6 receptor antibody MR16-1 has been shown to suppress inflammation after SCI and promote recovery of motor function. The purpose of this study was to analyze the effects of MR16-1 on the expression patterns of phospholipids in the spinal cord in a mouse model of SCI. Eight-week-old C57BL/6JJmsSlc mice were used in this study. Laminectomy was performed at the ninth and tenth thoracic levels (T9-T10), and contusion injury of the spinal cord was induced at level T10. Immediately after SCI, mice were intraperitoneally injected with a single dose of MR16-1 (MR16-1 group) or a single dose of phosphate-buffered saline of the same volume (control group). Imaging mass spectrometry was performed to visualize phosphatidylcholine (PC) expression in the spinal cord 7 days after SCI. We found that MR16-1 treatment suppressed the infiltration of immune cells after SCI, and was able to increase the locomotor function post-injury. Phospholipid imaging revealed that the MR16-1 was able to prevent the reduction of docosahexaenoic acid (DHA)-containing PC in comparison with the control group. We also observed high levels of glial fibrillary acidic protein (GFAP) at the site of DHA-containing PC expression in the MR16-1 group. These results suggest that MR16-1 treatment influences the DHA-containing PC composition of GFAP-positive cells at the injury site as early as 7 days post-SCI.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Ácidos Docosahexaenoicos/metabolismo , Interleucina-6/metabolismo , Fármacos Neuroprotectores/farmacología , Fosfatidilcolinas/metabolismo , Traumatismos de la Médula Espinal/tratamiento farmacológico , Traumatismos de la Médula Espinal/fisiopatología , Animales , Modelos Animales de Enfermedad , Femenino , Proteína Ácida Fibrilar de la Glía , Miembro Posterior/efectos de los fármacos , Miembro Posterior/fisiopatología , Locomoción/efectos de los fármacos , Locomoción/fisiología , Macrófagos/efectos de los fármacos , Macrófagos/fisiología , Ratones Endogámicos C57BL , Microglía/efectos de los fármacos , Microglía/fisiología , Proteínas del Tejido Nervioso/metabolismo , Distribución Aleatoria , Recuperación de la Función/efectos de los fármacos , Recuperación de la Función/fisiología , Transducción de Señal/efectos de los fármacos , Médula Espinal/efectos de los fármacos , Médula Espinal/patología , Médula Espinal/fisiopatología , Traumatismos de la Médula Espinal/patología , Vértebras Torácicas
14.
Cell Death Dis ; 4: e919, 2013 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-24232095

RESUMEN

Genetic and epidemiologic evidence suggests that cellular energy homeostasis is critically associated with Parkinson's disease (PD) pathogenesis. Here we demonstrated that genetic deletion of Poly (ADP-ribose) polymerase 1 completely blocked 6-hydroxydopamine-induced dopaminergic neurodegeneration and related PD-like symptoms. Hyperactivation of PARP-1 depleted ATP pools in dopaminergic (DA) neurons, thereby activating AMP-activated protein kinase (AMPK). Further, blockade of AMPK activation by viral infection with dominant-negative AMPK strongly inhibited DA neuronal atrophy with moderate suppression of nuclear translocation of apoptosis-inhibiting factor (AIF), whereas overactivation of AMPK conversely strengthened the 6-OHDA-induced DA neuronal degeneration. Collectively, these results suggest that manipulation of PARP-1 and AMPK signaling is an effective therapeutic approach to prevent PD-related DA neurodegeneration.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Dopamina/metabolismo , Neuronas/citología , Enfermedad de Parkinson/enzimología , Enfermedad de Parkinson/patología , Proteínas Quinasas Activadas por AMP/genética , Animales , Western Blotting , Cromatografía Líquida de Alta Presión , Modelos Animales de Enfermedad , Masculino , Espectrometría de Masas , Ratones , Ratones Noqueados , Neuronas/metabolismo , Enfermedad de Parkinson/metabolismo , Poli(ADP-Ribosa) Polimerasas/genética , Poli(ADP-Ribosa) Polimerasas/metabolismo
15.
Placenta ; 31(3): 245-8, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20116095

RESUMEN

Placental villi play pivotal roles in the feto-maternal transportation and phospholipids constitute major part of villous membrane. However, the functional contributions as well as pathological roles of placental phospholipids are yet to be fully clarified, because tissue distribution of phospholipids in the placental villi has not been identified. Recently, we have been developing and optimizing an imaging system based on a matrix-assisted laser desorption ionization (MALDI)-based mass spectrometer, which provides clear two-dimensional molecular identification with highly sensitive mass spectrometry from mixtures of ions generated on tissue surfaces. In the present study, we applied this technology to the molecular identification of phospholipids in the human term placenta and found that sphingomyelin (d18:1/16:0) and phosphatidylcholine (16:0/20:4) were distributed differently between stem and terminal villi. This methodology detected a distinct tissue distribution of phosphatidylcholine (16:0/20:4) of terminal villi, coupling with arachidonic acid (AA), which might be a clue leading to the future investigation of the possible involvement the synthetic cascade of eicosanoids in the physiology as well as pathological development of terminal villi, such as fetal growth restriction and/or fetal hypoxia, since terminal villi plays the central roles for nutrient and oxygen supply from maternal to fetal circulation.


Asunto(s)
Vellosidades Coriónicas/metabolismo , Fosfolípidos/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Espectrometría de Masas en Tándem/métodos , Vellosidades Coriónicas/química , Vellosidades Coriónicas/ultraestructura , Femenino , Humanos , Fosfolípidos/química , Embarazo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/instrumentación , Espectrometría de Masas en Tándem/instrumentación
16.
Neuroscience ; 168(1): 219-25, 2010 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-20362643

RESUMEN

To develop an effective neuroprotective strategy against ischemic injury, it is important to identify the key molecules involved in the progression of injury. Direct molecular analysis of tissue using mass spectrometry (MS) is a subject of much interest in the field of metabolomics. Most notably, imaging mass spectrometry (IMS) allows visualization of molecular distributions on the tissue surface. To understand lipid dynamics during ischemic injury, we performed IMS analysis on rat brain tissue sections with focal cerebral ischemia. Sprague-Dawley rats were sacrificed at 24 h after middle cerebral artery occlusion, and brain sections were prepared. IMS analyses were conducted using matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MALDI-TOF MS) in positive ion mode. To determine the molecular structures, the detected ions were subjected to tandem MS. The intensity counts of the ion signals of m/z 798.5 and m/z 760.5 that are revealed to be a phosphatidylcholine, PC (16:0/18:1) are reduced in the area of focal cerebral ischemia as compared to the normal cerebral area. In contrast, the signal of m/z 496.3, identified as a lyso-phosphatidylcholine, LPC (16:0), was clearly increased in the area of focal cerebral ischemia. In IMS analyses, changes of PC (16:0/18:1) and LPC (16:0) are observed beyond the border of the injured area. Together with previous reports--that PCs are hydrolyzed by phospholipase A(2) (PLA(2)) and produce LPCs,--our present results suggest that LPC (16:0) is generated during the injury process after cerebral ischemia, presumably via PLA(2) activation, and that PC (16:0/18:1) is one of its precursor molecules.


Asunto(s)
Encéfalo/metabolismo , Ataque Isquémico Transitorio/metabolismo , Lisofosfatidilcolinas/biosíntesis , Animales , Infarto de la Arteria Cerebral Media/complicaciones , Ataque Isquémico Transitorio/etiología , Espectrometría de Masas , Ratas , Ratas Sprague-Dawley
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