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1.
Case Rep Emerg Med ; 2023: 8829652, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37691692

RESUMEN

Background. A large thrombus entrapped in the patent foramen ovale (PFO) is an extremely rare condition. Moreover, it is considered even rarer after temporary inferior vena cava filter (TIVCF) placement for the prevention of fatal pulmonary embolism due to venous thromboembolism (VTE). Case Report. A 58-year-old man presented with syncope following chest pain and dyspnea due to PE exacerbation during TIVCF protection, which then led to cardiogenic shock. Echocardiography revealed a large thrombus entrapped in the PFO, and computed tomography (CT) showed a bilateral pulmonary artery embolism. The patient was treated with open surgical embolectomy for a pulmonary artery thrombus and PFO thrombus with simultaneous closure of the PFO. The patient's postoperative course was uneventful. Results and Conclusion. Surgical embolectomy was useful with respect to the feasibility of resection of both intracardiac thrombus and pulmonary artery thrombus performed simultaneously, contributing to the prevention of systemic embolisms, and echocardiography plays an important role for early diagnosis.

2.
Opt Lett ; 47(14): 3383-3386, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35838685

RESUMEN

This Letter presents the first, to the best of our knowledge, demonstration of noncritically birefringent-phase-matched parametric downconversion, which is associated with stimulated emission via vibronic transition in a laser gain medium. The so-called self-difference frequency generation is realized along the a-axis of a Cr:CdSe single crystal pumped by a Tm:YAG laser pulse at 2.013 µm, directly producing an infrared spectrum centered at 9 µm with the maximized effective nonlinearity. The light source, which benefits from the broad vibronic spectroscopic properties together with the wide transparency range of the host material, is expected to generate noncritically phase-matched, mid-infrared spectra beyond 20 µm along with birefringence engineering in the solid solution Cr:CdSxSe1-x.

3.
J Nucl Cardiol ; 29(6): 2920-2933, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-34704218

RESUMEN

BACKGROUND: Immunoglobulin G4-related disease (IgG4-RD) is characterized by the infiltration of IgG4-positive plasma cells and fibrosclerotic inflammation in multiple organs. Although vascular complications are present in some patients with IgG4-RD, vascular and/or perivascular inflammatory activity compared to control subjects remains unknown. This study sought to investigate vascular/perivascular inflammation in IgG4-RD patients compared to control subjects using 18F-fluorodeoxyglucose-positron emission tomography combined with computed tomography (FDG-PET/CT). METHODS: We examined 37 consecutive patients diagnosed as IgG4-RD (29 males, mean age of 64.3 ± 8.3 years old), who underwent FDG-PET/CT. Thirty-seven age- and gender-matched subjects without IgG4-RD were employed as controls. Vascular/perivascular inflammation was quantified by blood-normalized standardized uptake value, known as a target-to-background ratio (TBR). RESULTS: All IgG4-RD patients presented with multiple region involvements. Twelve (32.4%) of the IgG4-RD patients had vascular complications, all of which appeared in the abdominal aorta. IgG4-RD patients had significantly higher TBR values in the descending aorta, abdominal aorta, and common iliac artery than control subjects. Also, IgG4-RD patients with vascular complication exhibited higher TBR values in the infra-renal aorta and common iliac artery than those without vascular complication. CONCLUSIONS: We found that vascular FDG activity is significantly elevated in IgG4-RD patients regardless of vascular complication than control subjects. FDG-PET/CT is a useful modality for assessing vascular/perivascular inflammation, which may contribute vascular complication in IgG4-RD patients.


Asunto(s)
Enfermedad Relacionada con Inmunoglobulina G4 , Vasculitis , Masculino , Humanos , Persona de Mediana Edad , Anciano , Enfermedad Relacionada con Inmunoglobulina G4/complicaciones , Enfermedad Relacionada con Inmunoglobulina G4/diagnóstico por imagen , Fluorodesoxiglucosa F18 , Tomografía Computarizada por Tomografía de Emisión de Positrones , Vasculitis/diagnóstico por imagen , Tomografía de Emisión de Positrones/métodos , Inflamación/diagnóstico por imagen , Radiofármacos
7.
J Med Ultrason (2001) ; 44(2): 211-214, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27858229

RESUMEN

Felt strips are widely used for reinforcement of the aortic stump in surgery for aortic dissection (AD). Postoperative hemolytic anemia (HA) due to an inverted internal felt strip at the aortic stump fixation for AD is extremely rare. A 70-year-old woman underwent ascending aorta replacement for acute type A AD, where both proximal and distal anastomotic sites were reinforced with Teflon felt strips. A week later, macroscopic hematuria and HA emerged. Three-dimensional transesophageal echocardiography (3D-TEE) demonstrated that the proximal inner felt strip turned up and protruded into the aortic inner lumen. At redo surgery, which was performed 2 weeks after the initial surgery, the findings of 3D-TEE were confirmed, and the inverted internal felt strip was replaced with a bovine pericardial strip. The findings of HA disappeared immediately after the second surgery. 3D-TEE is a very informative, valuable modality for accurate diagnosis that leads to a safe surgery.


Asunto(s)
Anemia Hemolítica/diagnóstico por imagen , Aneurisma de la Aorta/cirugía , Disección Aórtica/cirugía , Prótesis Vascular/efectos adversos , Ecocardiografía Tridimensional , Ecocardiografía Transesofágica , Anciano , Anemia Hemolítica/etiología , Disección Aórtica/diagnóstico por imagen , Aneurisma de la Aorta/diagnóstico por imagen , Ecocardiografía Tridimensional/métodos , Ecocardiografía Transesofágica/métodos , Femenino , Humanos , Reoperación
8.
Cell Biol Int ; 40(3): 269-76, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26514426

RESUMEN

Increased A disintegrin and metalloprotease 17 (ADAM17) expression in vascular smooth muscle cells (VSMC) is implicated in the development of cardiovascular diseases including atherosclerosis and hypertension. Although cilostazol, type III phosphodiesterase (PDE III) inhibitor, has recently been found to inhibit VSMC proliferation, the mechanisms remain largely unclear. Here, we hypothesized that cilostazol regulates the ADAM17 expression in VSMC. In cultured VSMC, interleukin (IL)-1α and IL-1ß significantly increased ADAM17 expression. MEK inhibitor U0126, NF-κB inhibitor BAY-11-7085, and siRNA targeting p65/RelA significantly inhibited IL-1α or IL-ß-induced ADAM17 expression. Cilostazol significantly inhibited IL-1α or IL-1ß-induced extracellular signal-regulated kinase (ERK) phosphorylation and ADAM17 expression. Unexpectedly, cilostamide, dibutryl cAMP, and forskolin did not affect IL-1-induced ADAM17 expression. Our results clearly demonstrated that IL-1 induces ADAM17 expression through ERK/NF-κB activation in VSMCs. Moreover, the inhibitory effects of cilostazol on IL-1-induced ADAM17 expression may be independent of the cAMP signaling pathway in VSMC. These novel findings may provide important clues to understanding the expression mechanisms of ADAM17 and the inhibitory mechanisms of cilostazol in VSMC proliferation.


Asunto(s)
Proteína ADAM17/metabolismo , AMP Cíclico/metabolismo , Interleucina-1/farmacología , Transducción de Señal/efectos de los fármacos , Tetrazoles/farmacología , Animales , Células Cultivadas , Cilostazol , Quinasas MAP Reguladas por Señal Extracelular , Masculino , Músculo Liso Vascular/citología , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/metabolismo , Fosforilación/efectos de los fármacos , Biosíntesis de Proteínas/efectos de los fármacos , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Ratas , Ratas Sprague-Dawley , Factor de Transcripción ReIA/antagonistas & inhibidores , Factor de Transcripción ReIA/genética , Factor de Transcripción ReIA/metabolismo
9.
J Orthop Sci ; 19(5): 809-19, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24859177

RESUMEN

BACKGROUND: Proteomics is recognized as a useful tool in the dynamic screening of plasma protein expression. This study aimed to identify increased expressions of novel plasma proteins in ovariectomized mice (ovx) using selective reaction monitoring (SRM) validation in combination with electrospray ionized-quadrupole time-of-flight mass spectrometry (ESI-Q-TOF-MS) screening. MATERIALS AND METHODS: Twenty-week-old female C57BL/6 mice were ovariectomized or subjected to surgical exposure of the ovaries alone (sham). Blood plasma protein at 4 weeks after these operations was pooled for the ovx and sham group each and separated on SDS-PAGE, and then digested by peptides, which were first differentially displayed by ESI-Q-TOF-MS analysis. Mass spectra of peptides upregulated more than twofold in ovx compared to sham mice were selected for protein identification by ESI-Q-TOF-MS. The selected peptides were further validated in independent samples by SRM using electrospray ionized-triple quadrupole-linear ion trap mass spectrometry (ESI-QqLIT-MS). Optimum transitions for SRM were manually chosen for their high specificity in identifying peptides derived from the candidate proteins. RESULTS: Differential analysis of peptides revealed 1,108 upregulated peptides in ovx compared with sham control mice. Among the upregulated peptides, 231 nonredundant proteins were identified. Validation analysis for the potential use of these proteins as markers of bone turnover was performed using ESI-QqLIT-MS. The four proteins from the plasma samples, namely mannose-binding lectin-C, major urinary protein 2, type I collagen alpha 2 chain, and tetranectin, were evaluated in a blinded manner. A statistically significant elevation of all four proteins in the plasma of ovx mice was confirmed by SRM. Of the four upregulated plasma proteins, tetranectin increased by almost 50 times in the ovx mice compared with the sham mice. CONCLUSIONS: On the basis of proteomics analysis, this study demonstrated that four plasma proteins were significantly elevated in the ovx mice; of these, tetranectin was markedly upregulated by almost 50 times compared with the sham mice.


Asunto(s)
Lectinas Tipo C/sangre , Osteoporosis Posmenopáusica/sangre , Ovariectomía , Proteómica , Animales , Biomarcadores/sangre , Colágeno Tipo I/sangre , Modelos Animales de Enfermedad , Electroforesis en Gel de Poliacrilamida , Femenino , Humanos , Lectina de Unión a Manosa/sangre , Ratones , Ratones Endogámicos C57BL , Osteoporosis Posmenopáusica/etiología , Proteínas/metabolismo , Reproducibilidad de los Resultados , Espectrometría de Masa por Ionización de Electrospray
10.
Front Aging Neurosci ; 5: 15, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23576984

RESUMEN

BACKGROUND: Alzheimer's disease (AD) differs from other forms of dementia in its relation to amyloid beta peptide (Aß42). Using a cell culture model we previously identified annexin A5, a Ca(2+), and phospholipid binding protein, as an AD biomarker. Plasma level of annexin A5 was significantly higher in AD patients compared to that in a control group. On the other hand, AD has been identified to share a number of clinical and pathological features with Dementia with Lewy bodies (DLB). The present study was done to examine whether or not plasma annexin A5 is a specific marker for AD, when being compared with the levels of DLB patients. As Apolipoprotein E (ApoE) gene subtype ε4 (ApoE-ε4) has been noticed as the probable genetic factor for AD, we also examined and compared ApoE genotype in both AD and DLB. METHODS: Blood samples were obtained from 150 patients with AD (aged 77.6 ± 6.5 years), 50 patients of DLB (79.4 ± 5.0) and 279 community-dwelling healthy elderly individuals of comparable age and sex (75.6 ± 8.1). All AD patients met NINCDS-ADRDA criteria and all DLB patients were diagnosed as probable DLB according to the latest consensus diagnostic criteria. Quantification was done using the Chemiluminescent Enzyme Immunoassay (CLEIA) Technique (SphereLight assay) using the monoclonal antibodies against annexin A5. DNA genotyping of ApoE was performed by distinguishing unique combinations of Hha1 fragments of PCR-amplified genomic DNA products. RESULTS: The plasma level of annexin A5 was significantly higher in AD patients than in the healthy individuals (control) (P < 0.0001). The plasma annexin A5 level was also significantly higher in DLB patients than in the control group (P < 0.0001). From the ROC curves with plasma annexin A5 concentrations, the mean areas under the curve were 0.863 and 0.838 for the AD/control and DLB/control, respectively. The rate of ApoE4 carrier status and the frequency of the ε4 allele were significantly higher in AD or DLB than in control and there was no significant difference between AD and DLB. CONCLUSIONS: These results suggest that both annexin A5 and ApoE4 are common markers for AD and DLB.

11.
Anal Sci ; 28(9): 833-6, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22975909

RESUMEN

The magnetic-force quartz crystal microbalance (QCM) method was attempted for the dynamic evaluation of chemical interactions. Thiol-modified magnetic particles bound to a QCM gold electrode of less than three layers were pulled by a magnetic force, and the dissociation dynamics of the magnetic particles was measured based on the change in the weight as a function of time under different temperatures. From an analysis of the dissociated layers and the activation energy for the dissociation, the chemical interactions between particles were evaluated.

12.
Pain ; 153(3): 532-539, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22249007

RESUMEN

Complex regional pain syndrome (CRPS) is characterized by persistent and severe pain after trauma or surgery; however, its molecular mechanisms in the peripheral nervous system are poorly understood. Using proteomics, we investigated whether injured peripheral nerves of CRPS patients have altered protein profiles compared with control nerves. We obtained nerve samples from 3 patients with CRPS-2 who underwent resection of part of an injured peripheral nerve. Sural nerves from fresh cadavers with no history of trauma or neuropathic pain served as controls. Proteomic analysis showed that the number and functional distribution of proteins expressed in CRPS and control nerves was similar. Interestingly, metallothionein was absent in the injured nerves of CRPS-2, although it was readily detected in control nerves. Western blotting further confirmed the absence of metallothionein in CRPS-2 nerves, and immunohistochemistry corroborated the deficiency of metallothionein expression in injured nerves from 5 of 5 CRPS patients and 2 of 2 patients with painful neuromas. In contrast, all control nerves, including 5 sural nerves from fresh cadavers and 41 nerves obtained from surgically resected tumors, expressed MT. Furthermore, expression of S100 as a marker for Schwann cells, and neurofilament M as a marker of axons was comparable in both CRPS-2 and controls. Metallothioneins are zinc-binding proteins that are probably involved in protection against injury and subsequent regeneration after CNS damage. Their absence from the injured peripheral nerves of patients with CRPS-2 suggests a potential pathogenic role in generating pain in the damaged peripheral nerves.


Asunto(s)
Causalgia/complicaciones , Metalotioneína/deficiencia , Traumatismos de los Nervios Periféricos/etiología , Traumatismos de los Nervios Periféricos/metabolismo , Proteómica/métodos , Nervio Sural/patología , Adulto , Anciano , Femenino , Humanos , Masculino , Espectrometría de Masas , Persona de Mediana Edad , Proteínas de Neurofilamentos/metabolismo , Proteínas S100/metabolismo , Nervio Sural/metabolismo
13.
Exp Hematol ; 39(11): 1101-12, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21782767

RESUMEN

OBJECTIVE: To elucidate the significance of early expression of CC-chemokine ligand motif 8 (CCL8) in mice with graft-vs.-host disease (GVHD), we investigated its induction mechanisms and correlation with overall survival rate in GVHD mice. Plasma CCL8 increases on day 5 of allogeneic transplantation, when signs of GVHD are barely detectable. Increase of allogeneic splenocytes in grafts exacerbates GVHD and leads to upregulation of plasma CCL8 on day 5. Overall survival is the gold standard in determining the severity of acute GVHD in mice, but the absence of clinical and/or pathological manifestations in the early phase make it difficult to estimate vital outcomes at this stage of allogeneic marrow transplantation. MATERIALS AND METHODS: After lethal irradiation, BALB/c mice received bone marrow transplantation from C57BL/6 mice. Survival rate was monitored and clinical and pathological scores of GVHD were examined. Coculture of BALB/c-derived dendritic cells and C57BL/6-derived splenocytes was performed. CCL8 was measured by immunoassay. RESULTS: The plasma CCL8 level at day 5 of transplantation was closely correlated with survival rate and clinical/pathological scores on day 14. In vitro study revealed that the BALB/c-derived dendritic cells expressed CCL8 upon stimulation of C57BL/6 CD4(+) T cells by cell interactions through major histocompatibility complex class II molecules. CONCLUSIONS: These investigations indicate that early and preclinical expression of CCL8 in plasma predicts overall survival of GVHD mice. Together with an involvement of allo-recognition in CCL8 expression, it suggests that CCL8 plays an important role in GVHD pathology.


Asunto(s)
Quimiocina CCL8/biosíntesis , Quimiocina CCL8/sangre , Enfermedad Injerto contra Huésped/mortalidad , Enfermedad Aguda , Animales , Trasplante de Médula Ósea/efectos adversos , Trasplante de Médula Ósea/mortalidad , Comunicación Celular/inmunología , Células Dendríticas/química , Células Dendríticas/inmunología , Ratones , Modelos Animales , Pronóstico , Tasa de Supervivencia , Linfocitos T/inmunología , Factores de Tiempo , Activación Transcripcional , Trasplante Homólogo
14.
J Neurosci Res ; 88(12): 2682-92, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20648654

RESUMEN

Alzheimer's disease (AD) differs from other forms of dementia in its relation to amyloid beta peptide (Abeta). Abeta, a proteolytic product of amyloid precursor proteins (APP), has a toxic effect on neuronal cells, which involves perturbation of their Ca(2+) homeostasis. This effect implies that changes of protein expression in neuronal cells with calcium stress should provide a molecular marker for this disease. In the present study, we used the supernatant from a neuronal cell culture after incubation with or without Abeta and isolated a Ca(2+)-dependent acidic phospholipid binding fraction to perform a proteomic study. Several unique proteins were identified after incubation with Abeta. We focused on annexin A5, among these proteins, because it binds both Ca(2+) and lipids likely to be involved in calcium homeostasis. Tg2576 transgenic mice (AD model) overexpressing mutant human APP showed a significant increase of annexin A5 in the brain cortex but not in other organs, including liver, kidney, lung, and intestine. In human plasma samples, the level of annexin A5 was significantly increased in a proportion of AD patients compared with a control group (P < 0.0001 in the logistic regression analysis). From the receiver operating characteristic (ROC) curve with plasma annexin A5 concentrations, the mean area under the curve (AUC 0.898) suggests that annexin A5 is a favorable marker for AD.


Asunto(s)
Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/diagnóstico , Anexina A5/biosíntesis , Corteza Cerebral/metabolismo , Modelos Animales de Enfermedad , Neuronas/metabolismo , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/patología , Precursor de Proteína beta-Amiloide/biosíntesis , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/fisiología , Animales , Anexina A5/sangre , Biomarcadores/sangre , Señalización del Calcio/fisiología , Técnicas de Cultivo de Célula/métodos , Células Cultivadas , Corteza Cerebral/patología , Femenino , Regulación de la Expresión Génica/fisiología , Homeostasis/genética , Homeostasis/fisiología , Humanos , Masculino , Ratones , Ratones Endogámicos ICR , Ratones Transgénicos , Neuronas/citología , Neuronas/patología , Especificidad de Órganos/genética , Especificidad de Órganos/fisiología
15.
FEBS Lett ; 583(19): 3265-8, 2009 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-19751727

RESUMEN

We recently reported that diacylglycerol kinase (DGK) alpha enhanced tumor necrosis factor-alpha (TNF-alpha)-induced activation of nuclear factor-kappaB (NF-kappaB). However, the signaling pathway between DGKalpha and NF-kappaB remains unclear. Here, we found that small interfering RNA-mediated knockdown of DGKalpha strongly attenuated protein kinase C (PKC) zeta-dependent phosphorylation of a large subunit of NF-kappaB, p65/RelA, at Ser311 but not PKCzeta-independent phosphorylation at Ser468 or Ser536. Moreover, knockdown and overexpression of PKCzeta suppressed and synergistically enhanced DGKalpha-mediated NF-kappaB activation, respectively. These results strongly suggest that DGKalpha positively regulates TNF-alpha-dependent NF-kappaB activation via the PKCzeta-mediated Ser311 phosphorylation of p65/RelA.


Asunto(s)
Diacilglicerol Quinasa/metabolismo , Proteína Quinasa C/metabolismo , Serina/metabolismo , Factor de Transcripción ReIA/metabolismo , Diacilglicerol Quinasa/genética , Humanos , Proteínas I-kappa B/metabolismo , Fosforilación , Interferencia de ARN
16.
J Biol Chem ; 284(43): 29559-70, 2009 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-19710016

RESUMEN

The Ras/B-Raf/C-Raf/MEK/ERK signaling cascade is critical for the control of many fundamental cellular processes, including proliferation, survival, and differentiation. This study demonstrated that small interfering RNA-dependent knockdown of diacylglycerol kinase eta (DGKeta) impaired the Ras/B-Raf/C-Raf/MEK/ERK pathway activated by epidermal growth factor (EGF) in HeLa cells. Conversely, the overexpression of DGKeta1 could activate the Ras/B-Raf/C-Raf/MEK/ERK pathway in a DGK activity-independent manner, suggesting that DGKeta serves as a scaffold/adaptor protein. By determining the activity of all the components of the pathway in DGKeta-silenced HeLa cells, this study revealed that DGKeta activated C-Raf but not B-Raf. Moreover, this study demonstrated that DGKeta enhanced EGF-induced heterodimerization of C-Raf with B-Raf, which transmits the signal to C-Raf. DGKeta physically interacted with B-Raf and C-Raf, regulating EGF-induced recruitment of B-Raf and C-Raf from the cytosol to membranes. The DGKeta-dependent activation of C-Raf occurred downstream or independently of the already known C-Raf modifications, such as dephosphorylation at Ser-259, phosphorylation at Ser-338, and interaction with 14-3-3 protein. Taken together, the results obtained strongly support that DGKeta acts as a novel critical regulatory component of the Ras/B-Raf/C-Raf/MEK/ERK signaling cascade via a previously unidentified mechanism.


Asunto(s)
Diacilglicerol Quinasa/metabolismo , Sistema de Señalización de MAP Quinasas/fisiología , Proteínas Proto-Oncogénicas B-raf/metabolismo , Proteínas Proto-Oncogénicas c-raf/metabolismo , Animales , Células COS , Membrana Celular/enzimología , Membrana Celular/genética , Chlorocebus aethiops , Citoplasma/enzimología , Citoplasma/genética , Diacilglicerol Quinasa/antagonistas & inhibidores , Diacilglicerol Quinasa/genética , Dimerización , Técnicas de Silenciamiento del Gen , Células HeLa , Humanos , Fosforilación/fisiología , Unión Proteica/fisiología , Procesamiento Proteico-Postraduccional/fisiología , Transporte de Proteínas/fisiología , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas c-raf/genética , ARN Interferente Pequeño/genética
17.
Biochim Biophys Acta ; 1791(4): 246-53, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19416640

RESUMEN

The delta-isozyme (type II) of diacylglycerol kinase (DGK) is known to positively regulate growth factor receptor signaling. DGKdelta, which is distributed to clathrin-coated vesicles, interacts with DGKdelta itself, protein kinase C and AP2alpha. To search for additional DGKdelta-interacting proteins, we screened a yeast two-hybrid cDNA library from HepG2 cells using aa 896-1097 of DGKdelta as a bait. We identified aa 184-317 (WD40 repeats 5-7) of receptor for activated C kinase 1 (RACK1), which interacts with various important signaling molecules, as a novel binding partner of DGKdelta. Co-immunoprecipitation analysis, using COS-7 cells co-expressing RACK1 and DGKdelta, revealed that RACK1 selectively interacted with DGKdelta, but not with type I DGKs, in mammalian cells. The interaction was dynamically regulated by phorbol ester. Intriguingly, DGKdelta appeared to recruit RACK1 to clathrin-coated vesicles and co-localized with RACK1. These results suggest that DGKdelta serves as an adaptor protein to regulate the localization of the versatile scaffold protein, RACK1.


Asunto(s)
Vesículas Cubiertas por Clatrina/metabolismo , Diacilglicerol Quinasa/metabolismo , Proteínas de Unión al GTP/metabolismo , Proteínas de Neoplasias/metabolismo , Receptores de Superficie Celular/metabolismo , Animales , Western Blotting , Células COS , Células Cultivadas , Chlorocebus aethiops , Diacilglicerol Quinasa/genética , Proteínas de Unión al GTP/genética , Humanos , Inmunoprecipitación , Riñón/citología , Riñón/enzimología , Microscopía Fluorescente , Proteínas de Neoplasias/genética , Receptores de Cinasa C Activada , Receptores de Superficie Celular/genética , Técnicas del Sistema de Dos Híbridos
18.
Appl Opt ; 48(9): 1668-74, 2009 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-19305464

RESUMEN

A high-pulse-repetition-frequency (PRF) pulsed light source in the deep ultraviolet region has been realized by a multiple wavelength conversion technique using a hybrid fiber/bulk amplifier system. Output of 199 nm with a power of 50 mW was achieved at 2.4 MHz PRF. The 1 microm amplifier consisted of a Yb-doped fiber amplifier and a Nd-doped YVO(4) amplifier. A 1.5 microm fiber master-oscillator power amplifier was employed as the other fundamental source. The amplifiers exhibited good amplification properties in pulse energy, polarization extinction ratio, and spectrum for nonlinear wavelength conversion.

19.
Curr Drug Targets ; 9(8): 626-40, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18691010

RESUMEN

Diacylglycerol (DAG) kinase (DGK) modulates the balance between the two signaling lipids, DAG and phosphatidic acid (PA), by phosphorylating (consuming) DAG to yield PA. Ten mammalian DGK isozymes have been identified to date. In addition to two or three cysteine-rich C1 domains (protein kinase C-like zinc finger structures) commonly conserved in all DGKs, these isoforms possess a variety of regulatory domains of known and/or predicted functions, such as a pair of EF-hand motifs, a pleckstrin homology domain, a sterile alpha motif domain, a MARCKS (myristoylated alanine-rich C kinase substrate) phosphorylation site domain and ankyrin repeats. Recent studies have revealed that DGK isozymes play pivotal roles in a wide variety of mammalian signal transduction pathways conducting growth factor/cytokine-dependent cell proliferation and motility, seizure activity, immune responses, cardiovascular responses and insulin receptor-mediated glucose metabolism. It is suggested that several DGK isozymes can serve as potential drug targets for cancer, epilepsy, autoimmunity, cardiac hypertrophy, hypertension and type II diabetes. Unfortunately, there are no DGK isozyme-specific inhibitors/activators at present. Development of these compounds is eagerly awaited for the development of novel drugs targeting DGKs.


Asunto(s)
Diacilglicerol Quinasa/efectos de los fármacos , Sistemas de Liberación de Medicamentos , Transducción de Señal , Animales , Diacilglicerol Quinasa/metabolismo , Diseño de Fármacos , Humanos , Isoenzimas/metabolismo , Ácidos Fosfatidicos/metabolismo , Fosforilación
20.
Structure ; 16(3): 380-7, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18334213

RESUMEN

The diacylglycerol kinase (DGK) enzymes function as regulators of intracellular signaling by altering the levels of the second messengers, diacylglycerol and phosphatidic acid. The DGK delta and eta isozymes possess a common protein-protein interaction module known as a sterile alpha-motif (SAM) domain. In DGK delta, SAM domain self-association inhibits the translocation of DGK delta to the plasma membrane. Here we show that DGK delta SAM forms a polymer and map the polymeric interface by a genetic selection for soluble mutants. A crystal structure reveals that DGKSAM forms helical polymers through a head-to-tail interaction similar to other SAM domain polymers. Disrupting polymerization by polymer interface mutations constitutively localizes DGK delta to the plasma membrane. Thus, polymerization of DGK delta regulates the activity of the enzyme by sequestering DGK delta in an inactive cellular location. Regulation by dynamic polymerization is an emerging theme in signal transduction.


Asunto(s)
Diacilglicerol Quinasa/química , Diacilglicerol Quinasa/metabolismo , Polímeros/metabolismo , Cristalografía por Rayos X , Dimerización , Activación Enzimática , Humanos , Modelos Biológicos , Modelos Moleculares , Peso Molecular , Estructura Terciaria de Proteína/fisiología , Transporte de Proteínas , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/metabolismo , Solubilidad , Distribución Tisular/fisiología
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