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1.
J Refract Surg ; 39(1): 48-55, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36630430

RESUMEN

PURPOSE: To investigate refractive prediction accuracy with the OA-2000 (Tomey), Anterion (Heidelberg Engineering), and IOLMaster 500 (Carl Zeiss Meditec AG) in patients with cataract. METHODS: Patients with cataract referred for phacoemulsification were enrolled and scanned with the OA-2000, Anterion, and IOLMaster 500 in random order. The success rate of axial length (AL) measurements per device was calculated and a chi-square test was used to identify the differences in acquisition rate between the three devices. The Bland-Altman method was used to appraise the agreement of biometric parameters between the three devices. Four different formulas (Barrett Universal II [BUII], Haigis, Holladay 1, and SRK/T) were included in the study. The parameters of refractive prediction accuracy comprised predictive error (PE), absolute PE (AE), and percentages of eyes with a PE within ±0.50, ±0.75, and ±1.00 diopters (D). RESULTS: The acquisition rates of AL measurements with the OA-2000 and Anterion were 97.35% and 94.70%, respectively (chi-square = 3.82, P > .05). A significantly lower acquisition rate of 84.82% was obtained with the IOLMaster 500 compared with the other two devices (P < .05). Bland-Altman analysis identified good agreement between the three biometers with narrow 95% limits of agreement for flat and steep keratometry (K1 and K2), anterior chamber depth (ACD), and AL. For PE, only the differences between the Anterion and IOLMaster 500 with the Barrett UII and Haigis formulas were statistically significant (P < .05). The three devices revealed no statistically significant differences in MAE, MedAE, and the proportion of eyes with a PE within ±0.50, ±0.75, and ±1.00 D (P > .05). CONCLUSIONS: The OA-2000 and Anterion showed a similarly higher acquisition rate of AL measurements than the IOLMaster 500 in patients with cataract. Good agreement for K1, K2, ACD, and AL was found between the three biometers. Regarding refractive prediction accuracy, the Anterion did not significantly outperform both the OA-2000 and IOLMaster 500. [J Refract Surg. 2023;39(1):48-55.].


Asunto(s)
Extracción de Catarata , Catarata , Lentes Intraoculares , Dispositivos Ópticos , Facoemulsificación , Humanos , Refracción Ocular , Catarata/diagnóstico , Facoemulsificación/métodos , Biometría/métodos , Óptica y Fotónica , Longitud Axial del Ojo , Estudios Retrospectivos
2.
J Glaucoma ; 31(7): 602-608, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35763682

RESUMEN

PURPOSE: The aim was to evaluate the repeatability and agreement of two swept-source optical coherence tomographers for anterior segment parameters in healthy subjects. PATIENTS AND METHODS: Automated mark of scleral spur and angle recess for the CASIA2 and manual mark of scleral spur and angle recess for the Anterion were performed, and then the measurement values of the related parameters were automatically generated. Subjects with pupil diameter (PD) differing by <15% between the 2 devices were included. PD, lens vault (LV), anterior chamber depth (ACD), angle to angle distance (ATA), anterior chamber width (ACW), anterior chamber angle (ACA), angle opening distance (AOD), and trabecular iris space area (TISA) were measured in the horizontal images with both CASIA2 and Anterion. Intraclass correlation coefficient (ICC) was used to evaluate intradevice repeatability. Bland-Altman plots were performed to assess the agreement between the 2 devices. RESULTS: Thirty-five right eyes of 35 subjects were included with a mean age of 25.60±3.00 years. The CASIA2 showed moderate to good intradevice repeatability (ICCs ranged from 0.786 to 0.989) whereas the Anterion showed good intradevice repeatability (ICCs ranged from 0.921 to 0.998) for anterior segment parameters. Compared with the CASIA2, the Anterion offered larger values of ACA500/750, AOD500/750, and TISA500/750 but smaller values of PD, LV, ACD, ATA, and ACW. Good agreement for PD, ACD, ATA, and ACW was detected with 95% limits of agreement of -1.02 to 1.02 mm, -0.11 to 0.14 mm, -0.17 to 0.19 mm, -0.13 to 0.28 mm, respectively. Poor agreement for LV, ACA500/750, AOD500/750, and TISA500/750 was achieved with the 2 devices. CONCLUSIONS: Anterion outperformed CASIA2 on intradevice repeatability. While agreement was noted for some parameters using manual Anterion and automated CASIA2 approaches, poor agreement of LV and angle parameters indicates that measurements from these optical coherence tomography devices should not be considered interchangeable.


Asunto(s)
Segmento Anterior del Ojo , Presión Intraocular , Adulto , Cámara Anterior/diagnóstico por imagen , Segmento Anterior del Ojo/diagnóstico por imagen , Humanos , Iris/diagnóstico por imagen , Tomografía de Coherencia Óptica/métodos , Adulto Joven
3.
Graefes Arch Clin Exp Ophthalmol ; 260(9): 2905-2911, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35488908

RESUMEN

PURPOSE: To assess the acquisition rate and agreement of axial length (AL) measurements with the OA-2000, Anterion, and IOLMaster 500 in cataractous patients. METHODS: In total, 298 eyes of 191 cataractous patients were enrolled and scanned with the three devices in random order. The success rate of AL measurements per device was calculated and a chi-square test was utilized to identify the differences in acquisition rate between the three devices. Logistic regression analysis was applied to evaluate the association of different cataract types and severity with the AL measurement acquisition rate. Bland-Altman plots were mapped to appraise the agreement of AL values. RESULTS: AL measurements were successfully achieved in 288 eyes (96.64%) with the OA-2000, in 282 eyes (94.30%) with the Anteiron, and in 246 eyes (82.55%) with the IOLMaster 500. Significant differences in the acquisition rate were found between either of the SS-OCT devices and IOLMaster 500 by chi-square analysis (P < 0.001). No significant difference was noted between OA-2000 and Anterion. Increasing severity of posterior subcapsular cataract was associated with a higher failure rate with the IOLMaster 500. Bland-Altman analysis identified good agreement between the three biometers with narrow 95% limits of agreement. CONCLUSIONS: The OA-2000 and Anterion showed similarly higher acquisition rate of AL measurements than IOLMaster 500 in cataractous patients. Good agreement for AL values was found between the three biometers in cataractous patients.


Asunto(s)
Longitud Axial del Ojo , Catarata , Cámara Anterior , Biometría , Humanos , Interferometría , Estudios Prospectivos , Reproducibilidad de los Resultados , Tomografía de Coherencia Óptica
4.
Graefes Arch Clin Exp Ophthalmol ; 260(7): 2271-2281, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35171331

RESUMEN

PURPOSE: To investigate the repeatability of Anterion and compare the agreement of ocular biometric measurements and predicted intraocular lens (IOL) powers with other three optical biometers. METHODS: Flat keratometry (Kf), steep keratometry (Ks), J0 and 45 vectors, central cornea thickness (CCT), anterior chamber depth (ACD), and axial length (AL) from the Anterion, IOLMaster 700, Lenstar LS 900, and OA-2000 were recorded. The IOL powers were calculated with the Hoffer Q, Holladay 1, SRK/T, and Haigis formulas. The repeatability was evaluated using the within-subject standard deviation (Sw), repeatability coefficient (RC), coefficient of variation (COV), and intraclass correlation coefficient (ICC). Inter-device agreement between the four biometers was assessed with the 95% limits of agreement. RESULTS: In total, 101 right eyes of 101 participants were enrolled. The Anterion showed good repeatability for all the included biometric parameters with all the CoV ≤ 0.30% and ICC ≥ 0.930 except for J45 with moderate repeatability (ICC was 0.849). Good agreement was found among the four devices for Kf, Ks, J0, J45, ACD, and AL. Generally, wide 95% LoA was found for the predicted IOL powers with the four IOL calculation formulas between the four devices. CONCLUSIONS: The Anterion showed good repeatability of biometric measurements for most parameters. Good agreement among the four optical biometers was achieved for all the parameters except for CCT and the predicted IOL power. The AL values exhibited the best repeatability with Anterion and the best agreement among the biometers in our study.


Asunto(s)
Longitud Axial del Ojo , Lentes Intraoculares , Cámara Anterior/anatomía & histología , Cámara Anterior/diagnóstico por imagen , Longitud Axial del Ojo/anatomía & histología , Biometría , Córnea/diagnóstico por imagen , Humanos , Estudios Prospectivos , Reproducibilidad de los Resultados , Tomografía de Coherencia Óptica
5.
J Refract Surg ; 37(10): 707-714, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34661478

RESUMEN

PURPOSE: To evaluate the differences in efficacy, predictability, safety, and visual quality between topography-guided customized ablation treatment (TCAT) and wavefront-optimized (WFO) laser in situ keratomileusis (LASIK) for the treatment of myopia with and without astigmatism. METHODS: A comprehensive literature search of PubMed, Embase, the Cochrane library, Web of Science, and ClinicalTrials was used to identify randomized controlled trials (RCTs) comparing TCAT-LASIK with WFO-LASIK for myopia with and without astigmatism up to September 2020. The references of all searched literature were checked as supplements. Literature was screened according to the inclusion and exclusion criteria and relative data were extracted. RevMan software version 5.3.0 (Cochrane Collaboration) was used for meta-analysis. RESULTS: A total of seven RCTs (1,168 eyes) were included. There were no statistically significant differences in the ratio of uncorrected distance visual acuity of 20/20 or better (relative risk [RR] = 1.01, 95% CI [0.97 to 1.06], P = .64) and 20/16 or better (RR = 0.96, 95% CI [0.80 to 1.16], P = .69). Compared with WFO-LASIK, TCAT-LASIK achieved a higher proportion of postoperative manifest refractive spherical equivalent within ±0.50 diopters of the target (RR = 1.06, 95% CI [1.02 to 1.11], P = .003) and less surgically induced higher order aberrations (weighted mean difference [WMD] = -0.11, 95% CI [-0.15 to -0.0], P < .00001), spherical aberrations (WMD = -0.04, 95% CI [-0.05 to -0.03], P < .00001), and coma (WMD = -0.15, 95% CI [-0.28 to -0.01], P = .03). No patient lost two or more lines of distance-corrected visual acuity postoperatively in the two groups. CONCLUSIONS: This meta-analysis suggests that both TCATLASIK and WFO-LASIK show excellent efficacy, predictability, and safety for myopia. TCAT-LASIK exhibited more accurate postoperative refraction predictability and less surgically induced higher order aberrations, spherical aberrations, and coma. More randomized, prospective, and large sample-sized studies are needed to confirm these conclusions in the long term. [J Refract Surg. 2021;37(10):707-714.].


Asunto(s)
Astigmatismo , Aberración de Frente de Onda Corneal , Queratomileusis por Láser In Situ , Miopía , Astigmatismo/cirugía , Humanos , Láseres de Excímeros/uso terapéutico , Miopía/cirugía , Estudios Prospectivos , Resultado del Tratamiento
6.
Huan Jing Ke Xue ; 40(2): 885-892, 2019 Feb 08.
Artículo en Chino | MEDLINE | ID: mdl-30628357

RESUMEN

Annual nitrous oxide (N2O) and nitric oxide (NO) emissions were measured within a 27 year fertilization experiment in Guanzhong Plain. Gas samples were collected using static chambers from June 2017 to June 2018. The primary objectives of this study were to quantify the variations in N2O and NO emissions and evaluate the effect of manure amendment on gas losses. Three treatments were set up in the field using a completely random block design. The control treatment (CK) remained unfertilized throughout the year. The synthetic fertilizers (NPK) and NPK plus dairy manure (NPKM) treatments received an annual nitrogen (N) input at a rate of 353 kg·hm-2. In the summer maize season, the NPK and NPKM treatments received urea as a N source at 188 kg·hm-2. In the winter wheat season, the NPK treatments received urea at 165 kg·hm-2. The NPKM treatment received the same amount of N as the NPK treatment but with 30% from urea and 70% from dairy manure. The results showed that N2O and NO emissions from the CK treatment were consistently low during the experimental period. Large emission peaks were captured in the NPK and NPKM treatments, mostly responding to fertilizer application and irrigation. The largest N2O and NO peaks were up to 103.0 g·(hm2·d)-1 and 71.0 g·(hm2·d)-1, respectively, and both occurred in the NPKM treatment during the summer maize season. The NO/N2O ratio was negatively related to soil water-filled pore space (P<0.01) at soil temperatures above 20℃ for the NPK and NPKM treatments, indicating the regulatory effect of soil temperature and water content on gas fluxes. Annual N2O emissions from the CK, NPK, and NPKM treatments were 0.21 kg·hm-2, 2.32 kg·hm-2, and 2.15 kg·hm-2, respectively, with a non-significant difference between the NPK and NPKM treatments (P=0.74). Annual NO emissions from the CK, NPK, and NPKM treatments were 0.23 kg·hm-2, 0.80 kg·hm-2, and 1.46 kg·hm-2, respectively, with a significant difference between the NPK and NPKM treatments (P<0.05). We concluded that long-term dairy manure amendment did not influence N2O emissions but increased NO emissions.


Asunto(s)
Fertilizantes , Estiércol , Óxido Nítrico/análisis , Óxido Nitroso/análisis , Triticum/crecimiento & desarrollo , Zea mays/crecimiento & desarrollo , Agricultura , Nitrógeno , Estaciones del Año , Suelo
7.
Cancer Commun (Lond) ; 38(1): 4, 2018 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-29784063

RESUMEN

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is the predominant subtype of esophageal carcinoma in China. This study was to develop a staging model to predict outcomes of patients with ESCC. METHODS: Using Cox regression analysis, principal component analysis (PCA), partitioning clustering, Kaplan-Meier analysis, receiver operating characteristic (ROC) curve analysis, and classification and regression tree (CART) analysis, we mined the Gene Expression Omnibus database to determine the expression profiles of genes in 179 patients with ESCC from GSE63624 and GSE63622 dataset. RESULTS: Univariate cox regression analysis of the GSE63624 dataset revealed that 2404 protein-coding genes (PCGs) and 635 long non-coding RNAs (lncRNAs) were associated with the survival of patients with ESCC. PCA categorized these PCGs and lncRNAs into three principal components (PCs), which were used to cluster the patients into three groups. ROC analysis demonstrated that the predictive ability of PCG-lncRNA PCs when applied to new patients was better than that of the tumor-node-metastasis staging (area under ROC curve [AUC]: 0.69 vs. 0.65, P < 0.05). Accordingly, we constructed a molecular disaggregated model comprising one lncRNA and two PCGs, which we designated as the LSB staging model using CART analysis in the GSE63624 dataset. This LSB staging model classified the GSE63622 dataset of patients into three different groups, and its effectiveness was validated by analysis of another cohort of 105 patients. CONCLUSIONS: The LSB staging model has clinical significance for the prognosis prediction of patients with ESCC and may serve as a three-gene staging microarray.


Asunto(s)
Biomarcadores de Tumor/genética , Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/genética , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , ARN Largo no Codificante/genética , Carcinoma de Células Escamosas/patología , Neoplasias Esofágicas/patología , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Análisis de Componente Principal , Pronóstico
8.
Cell Mol Life Sci ; 75(14): 2643-2661, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29428966

RESUMEN

The human riboflavin transporter-3 (encoded by SLC52A3) plays a prominent role in riboflavin absorption. Interestingly, abnormal expression patterns of SLC52A3 in multiple types of human cancers have been recently noted. However, the molecular mechanisms underlying its dysregulation remain unclear. In this study, we find that SLC52A3 has two transcript variants that differ in the transcriptional start site, and encode different proteins: SLC52A3a and SLC52A3b. Importantly, aberrant expressions of SLC52A3 are associated with stepwise development of esophageal squamous cell carcinoma (ESCC) as well as the survival rates of ESCC patients. Functionally, SLC52A3a, but not SLC52A3b, strongly promotes the proliferation and colony formation of ESCC cells. Furthermore, SLC52A3 5'-flanking regions contain NF-κB p65/Rel-B-binding sites, which are crucial for mediating SLC52A3 transcriptional activity in ESCC cells. Chromatin immunoprecipitation and electrophoretic mobility shift assay reveal that p65/Rel-B bind to 5'-flanking regions of SLC52A3. Accordingly, NF-κB signaling upregulates SLC52A3 transcription upon TNFα stimulation. Taken together, these results elucidate the mechanisms underlying SLC52A3 overexpression in ESCC. More importantly, our findings identify SLC52A3 as both a predictive and prognostic biomarker for this deadly cancer.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Factor de Transcripción ReIA/metabolismo , Factor de Transcripción ReIB/metabolismo , Región de Flanqueo 5'/genética , Adulto , Anciano , Secuencia de Bases , Sitios de Unión/genética , Biomarcadores de Tumor/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patología , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Proteínas de Transporte de Membrana/genética , Persona de Mediana Edad , Pronóstico , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Análisis de Supervivencia
9.
Sci Rep ; 7(1): 7883, 2017 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-28801574

RESUMEN

Plasma oxytocin (OT) originates from secretion from the pituitary gland into the circulation and from absorption of OT in mother's milk into the blood via intestinal permeability. However, the molecular mechanism underlying the absorption of OT remains unclear. Here, we report that plasma OT concentrations increased within 10 min after oral delivery in postnatal day 1-7 mice. However, in Receptors for Advanced Glycation End Products (RAGE) knockout mice after postnatal day 3, an identical OT increase was not observed. In adult mice, plasma OT was also increased in a RAGE-dependent manner after oral delivery or direct administration into the intestinal tract. Mass spectrometry evaluated that OT was absorbed intact. RAGE was abundant in the intestinal epithelial cells in both suckling pups and adults. These data highlight that OT is transmitted via a receptor-mediated process with RAGE and suggest that oral OT supplementation may be advantageous in OT drug development.


Asunto(s)
Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Oxitocina/metabolismo , Receptor para Productos Finales de Glicación Avanzada/metabolismo , Animales , Animales Recién Nacidos , Femenino , Lactancia , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Oxitocina/administración & dosificación , Oxitocina/sangre , Permeabilidad , Receptor para Productos Finales de Glicación Avanzada/genética
10.
ScientificWorldJournal ; 2014: 702561, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24701184

RESUMEN

In order to calculate the ground movement induced by displacement piles driven into horizontal layered strata, an axisymmetric model was built and then the vertical and horizontal ground movement functions were deduced using stochastic medium theory. Results show that the vertical ground movement obeys normal distribution function, while the horizontal ground movement is an exponential function. Utilizing field measured data, parameters of these functions can be obtained by back analysis, and an example was employed to verify this model. Result shows that stochastic medium theory is suitable for calculating the ground movement in pile driving, and there is no need to consider the constitutive model of soil or contact between pile and soil. This method is applicable in practice.


Asunto(s)
Modelos Teóricos , Procesos Estocásticos
11.
Dalton Trans ; 42(48): 16762-72, 2013 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-24077612

RESUMEN

New bis(N,N-trimethylsilylarylamidinate) zirconium dichloride complexes with various carbon substituents were prepared, and their solid as well as solution state structures were studied. In the polymerization of propylene, after activation by MAO, these catalysts provided two fractions. Ether soluble polymers were obtained at a low activity as sticky polymers with lower molecular weights, except with the o-OMe substituted complex. The solid fractions were composed of a highly isotactic polymer and a moderately syndiotactic polymer. An interesting linear correlation was found between the rates of the 2,1 and 3,1 insertions for the ether soluble fractions.

12.
Zhonghua Yu Fang Yi Xue Za Zhi ; 45(2): 143-5, 2011 Feb.
Artículo en Chino | MEDLINE | ID: mdl-21426794

RESUMEN

OBJECTIVE: To investigate the sanitary status of urban secondary water supply facilities in Haidian district of Beijing. METHODS: Adopting the quantitative classification table drafted by the Bureau for Sanitation Inspection and Supervision of Haidian district, we carried quantitative classification (A, B, C grade) on all 1725 secondary water supply facilities in Haidian district for two times. At the same time, we collected 20 residential areas with stratified random sampling method. As the public points in the first quantitative classification, the effect of level publicity on changing the sanitary grade of the secondary water supply facilities were observed. RESULTS: In the first two times of quantitative classification, A-level and B-level secondary water supply facilities took up 81.04% (1398/1725) and 89.04% (1536/1725) of all secondary water supply facilities respectively; the ratio of effective sanitary permits achieved 86.14% (1486/1725) and 92.35% (1593/1725) respectively; and the ratio of effective water quality test reports achieved 86.60% (1494/1725) and 97.10% (1675/1725) respectively. There were 52 secondary water supply facilities in 20 collected areas, including 8 A-level, 27 B-level and 17 C-level secondary water supply facilities before level publicity, and 19, 29 and 4 after level publicity. The impact of level publicity on changing the sanitary grade of the secondary water supply facilities was statistically significant (χ(2) = 12.60, P = 0.002). CONCLUSION: The city secondary water supply facilities in Haidian district are overall in good sanitary conditions. Quantitative classification and level publicity can effectively improve the sanitary status of secondary water supply facilities.


Asunto(s)
Saneamiento , Salud Urbana , Abastecimiento de Agua , China
13.
Dalton Trans ; (1): 111-8, 2009 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-19081978

RESUMEN

The 16-electron half-sandwich complexes Cp*M[S(2)C(2)(B(10)H(10))] (M = Ir (1), Rh (2), Co (3)) react with [Ru(COD)Cl(2)](x) under basic conditions at 35-40 degrees C to give different hetero-dinuclear clusters {Cp*M[S(2)C(2)(B(9)H(10))]}Ru(COD) (M = Ir (1a), Rh (2a), Co (3a)) and {Cp*M[S(2)C(2)(B(9)H(9))]}Ru(COD)(OCH(3)) (M = Ir (1b), Rh (2b), Co (3b)) with open carborane cages. Moreover, B-H-->Ru bridge bonds were observed in complexes 1a, 2a,3a . In reaction a, minor products trinuclear complex {Cp*Ir[S(2)C(2)(B(10)H(10))]}(2)Ru (1c) and methoxyl-disubstituted complex Cp*Ir[S(2)C(2)(B(10)H(8))(OCH(3))(2)] (1d) were successfully isolated. However, when the reaction temperature decreased to 0-10 degrees C, the kinetically-controlled products, mono-substituted complex Cp*Ir[S(2)C(2)(B(10)H(9))(OCH(3))] (1e) and disubstituted complex Cp*Ir[S(2)C(2)(B(10)H(8))(OCH(3))(2)] (1d), were isolated as the main products; nevertheless, the thermodynamically-controlled products, open-carborane complexes 1a and 1b , were isolated as the minor products. In complex Cp*Co[S(2)C(2)(B(9)H(10))]Ru(C(7)H(8)) (3c), one COD coordinated to ruthenium has been replaced by toluene. The reactions demonstrate that different types of products can be obtained by controlling the reaction conditions. All these new complexes have been characterized by IR, (1)H NMR, (11)B NMR and elemental analyses. The molecular structures of 1a, 1b, 1c, 1d, 1e, 2a and 3a have also been determined by single-crystal X-ray diffraction analyses.

14.
Neurosci Res ; 57(3): 339-46, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17173996

RESUMEN

The role of cyclic ADP-ribose (cADPR) and its synthetic enzyme, CD38, as a downstream signal of muscarinic acetylcholine receptors (mAChRs) was examined in neuroblastoma cells expressing M1 mAChRs (NGM1). NGM1 cells were further transformed with both wild-type and mutant (C119K/C201E) human CD38. The dual transformed cells exhibited higher cADPR formation than ADPR production and elevated intracellular free Ca(2+) concentrations ([Ca(2+)](i)) in response to ACh. These phenotypes were analyzed in detail in a representative CD38 clone. The intracellular cADPR concentration by ACh application was significantly increased by CD38 overexpression. Digital image analysis by a confocal microscopy revealed that topographical distribution of the sites of Ca(2+) release was unchanged between control and overexpressed cells. These results indicate that cADPR is an intracellular messenger of Ca(2+) signalling, suggesting that CD38 can contribute to mAChR-cADPR signalling.


Asunto(s)
ADP-Ribosil Ciclasa 1/metabolismo , ADP-Ribosil Ciclasa/metabolismo , Acetilcolina/metabolismo , Señalización del Calcio/fisiología , ADP-Ribosa Cíclica/metabolismo , Receptores Muscarínicos/metabolismo , ADP-Ribosil Ciclasa 1/genética , Acetilcolina/farmacología , Animales , Calcio/metabolismo , Señalización del Calcio/efectos de los fármacos , Línea Celular Tumoral , Células Clonales/efectos de los fármacos , Células Clonales/metabolismo , Humanos , Ratones , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Fenotipo , Ratas , Receptores Muscarínicos/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/fisiología
15.
FEBS Lett ; 580(20): 4857-60, 2006 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-16905135

RESUMEN

ADP-ribosyl cyclase activity in the crude membrane fraction of neuroblastomaxglioma NGPM1-27 hybrid cells was measured by monitoring [(3)H] cyclic ADP-ribose (cADPR) formation from [(3)H] NAD(+). Bradykinin (BK) at 100nM increased ADP-ribosyl cyclase activity by about 2.5-fold. Application of 300nM BK to living NGPM1-27 cells decreased NAD(+) to 78% of the prestimulation level at 30s. In contrast, intracellular cADPR concentrations were increased by 2-3-fold during the period from 30 to 120s after the same treatment. Our results suggest that cADPR is one of the second messengers downstream of B(2) BK receptors.


Asunto(s)
ADP-Ribosil Ciclasa/metabolismo , Bradiquinina/farmacología , Línea Celular Tumoral/efectos de los fármacos , ADP-Ribosa Cíclica/metabolismo , NAD/metabolismo , Vasodilatadores/farmacología , Animales , Membrana Celular/química , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Células Híbridas/citología , Células Híbridas/efectos de los fármacos , Ratones , Neuroblastoma , Ratas , Sistemas de Mensajero Secundario/fisiología
16.
Biochem Biophys Res Commun ; 335(3): 920-4, 2005 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-16105661

RESUMEN

The role of cyclic ADP-ribose (cADPR) as the downstream signal of neuronal muscarinic acetylcholine receptors (mAChRs) and the enzyme responsible for its synthesis, ADP-ribosyl cyclase, were examined in the rat superior cervical ganglion (SCG). Application of acetylcholine or other mAChR agonists increased the ADP-ribosyl cyclase activity by about 250-300% in crude membrane fractions from the SCG of 14-day-old rats. This effect was inhibited by atropine or by the M1-mAChR antagonist, pirenzepine, and was mimicked by GTP. These results indicate that the M1 mAChRs couple to the membrane-bound form of ADP-ribosyl cyclase and suggest that cADPR is a second messenger of M1 mAChR signaling in nervous tissue.


Asunto(s)
Acetilcolina/farmacología , ADP-Ribosa Cíclica/biosíntesis , Ganglios/efectos de los fármacos , Receptor Muscarínico M1/metabolismo , Animales , Femenino , Ganglios/metabolismo , Masculino , Ratas , Ratas Wistar
17.
Neurosci Res ; 51(3): 231-4, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15710486

RESUMEN

The second messenger for closure of M/KCNQ potassium channels in post-ganglionic neurons and central neurons had remained as a 'mystery in the neuroscience field' for over 25 years. However, recently the details of the pathway leading from muscarinic acetylcholine receptor (mAChR)-stimulation to suppression of the M/KCNQ-current were discovered. A key molecule is A-kinase anchoring protein (AKAP; AKAP79 in human, or its rat homolog, AKAP150) which forms a trimeric complex with protein kinase C (PKC) and KCNQ channels. AKAP79 or 150 serves as an adapter that brings the anchored C-kinase to the substrate KCNQ channel to permit the rapid and 'definitive' phosphorylation of serine residues, resulting in avoidance of signal dispersion. Thus, these findings suggest that mAChR-induced short-term modulation (or memory) does occur within the already well-integrated molecular complex, without accompanying Hebbian synapse plasticity. However, before this identity is confirmed, many other modulators which affect M-currents remain to be addressed as intriguing issues.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/fisiología , Canales de Potasio con Entrada de Voltaje/fisiología , Proteína Quinasa C/fisiología , Receptores Muscarínicos/fisiología , Proteínas de Anclaje a la Quinasa A , Animales , Canales de Potasio KCNQ , Modelos Biológicos
18.
J Neurochem ; 85(5): 1148-58, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12753074

RESUMEN

Cyclic ADP-ribose (cADP-ribose) is a putative second messenger or modulator. However, the role of cADP-ribose in the downstream signals of the metabotropic glutamate receptors (mGluRs) is unclear. Here, we show that glutamate stimulates ADP-ribosyl cyclase activity in rat or mouse crude membranes of retina via group III mGluRs or in superior cervical ganglion via group I mGluRs. The retina of mGluR6-deficient mice showed no increase in the ADP-ribosyl cyclase level in response to glutamate. GTP enhanced the initial rate of basal and glutamate-stimulated cyclase activity. GTP-gamma-S also stimulated basal activity. To determine whether the coupling mode of mGluRs to ADP-ribosyl cyclase is a feature common to individual cloned mGluRs, we expressed each mGluR subtype in NG108-15 neuroblastoma x glioma hybrid cells. The glutamate-induced stimulation of the cyclase occurs preferentially in NG108-15 cells over-expressing mGluRs1, 3, 5, and 6. Cells expressing mGluR2 or mGluRs4 and 7 exhibit inhibition or no coupling, respectively. Glutamate-induced activation or inhibition of the cyclase activity was eliminated after pre-treatment with cholera or pertussis toxin, respectively. Thus, the subtype-specific coupling of mGluRs to ADP-ribosyl cyclase via G proteins suggests that some glutamate-evoked neuronal functions are mediated by cADP-ribose.


Asunto(s)
ADP-Ribosil Ciclasa/metabolismo , Glioma/metabolismo , Neuroblastoma/metabolismo , Neuronas/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Retina/metabolismo , Ganglio Cervical Superior/metabolismo , ADP-Ribosil Ciclasa/química , ADP-Ribosil Ciclasa/efectos de los fármacos , Adenosina Difosfato Ribosa/biosíntesis , Animales , Membrana Celular/enzimología , Células Cultivadas , Toxina del Cólera/farmacología , Activación Enzimática/efectos de los fármacos , Glioma/química , Ácido Glutámico/farmacología , Guanosina Trifosfato/análogos & derivados , Guanosina Trifosfato/farmacología , Ratones , Ratones Noqueados , Neuroblastoma/química , Neuronas/química , Neuronas/citología , Ratas , Ratas Wistar , Retina/química , Retina/citología , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Ganglio Cervical Superior/química , Ganglio Cervical Superior/citología
19.
Nat Neurosci ; 6(6): 564-71, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12754513

RESUMEN

M-type (KCNQ2/3) potassium channels are suppressed by activation of G(q/11)-coupled receptors, thereby increasing neuronal excitability. We show here that rat KCNQ2 can bind directly to the multivalent A-kinase-anchoring protein AKAP150. Peptides that block AKAP150 binding to the KCNQ2 channel complex antagonize the muscarinic inhibition of the currents. A mutant form of AKAP150, AKAP(DeltaA), which is unable to bind protein kinase C (PKC), also attenuates the agonist-induced current suppression. Analysis of recombinant KCNQ2 channels suggests that targeting of PKC through association with AKAP150 is important for the inhibition. Phosphorylation of KCNQ2 channels was increased by muscarinic stimulation; this was prevented either by coexpression with AKAP(DeltaA) or pretreatment with PKC inhibitors that compete with diacylglycerol. These inhibitors also reduced muscarinic inhibition of M-current. Our data indicate that AKAP150-bound PKC participates in receptor-induced inhibition of the M-current.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Proteínas Portadoras/metabolismo , Membrana Celular/metabolismo , Inhibición Neural/fisiología , Neuronas/metabolismo , Canales de Potasio/metabolismo , Proteínas de Anclaje a la Quinasa A , Animales , Proteínas Portadoras/efectos de los fármacos , Proteínas Portadoras/genética , Membrana Celular/efectos de los fármacos , Células Cultivadas , Diglicéridos/antagonistas & inhibidores , Diglicéridos/metabolismo , Inhibidores Enzimáticos/farmacología , Ganglios Simpáticos/efectos de los fármacos , Ganglios Simpáticos/metabolismo , Canal de Potasio KCNQ2 , Sustancias Macromoleculares , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/fisiología , Agonistas Muscarínicos/farmacología , Mutación/genética , Inhibición Neural/efectos de los fármacos , Neuronas/efectos de los fármacos , Fragmentos de Péptidos/farmacología , Fosforilación/efectos de los fármacos , Canales de Potasio/efectos de los fármacos , Canales de Potasio con Entrada de Voltaje , Unión Proteica/efectos de los fármacos , Unión Proteica/fisiología , Isoformas de Proteínas/genética , Isoformas de Proteínas/farmacología , Proteína Quinasa C/antagonistas & inhibidores , Proteína Quinasa C/metabolismo , Ratas , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología
20.
Autoimmunity ; 35(3): 191-9, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12389644

RESUMEN

Experimental autoimmune encephalomyelitis (EAE) is an animal model of human multiple sclerosis that requires the activation of autoreactive T cells for the expression of pathology. EAE has been most frequently studied in the Lewis rat model as well as in several murine models of EAE including the PLJ and B10PL strains. In the present study we describe a novel model of EAE induced in the Wistar rat strain by immunization with guinea pig spinal cord antigens and pertussis toxin (PT). T cell responses were induced to myelin basic protein. Autoreactive T cells could be totally blocked by the in vitro treatment with CTLA4Ig, a protein that blocks the costimulation of autoreactive T cells. The addition of IL-2 could reverse the inhibition seen in vitro with CTLA4Ig. The effects of inhibition of B7 costimulation were also examined by an analysis of cytokine responses and IL-2 receptor on T cells. CTLA4Ig treatment in vitro reduced the expression of IL-2 receptor on T cells, enhanced T cell apoptosis and decreased the synthesis of IL-2, IFN-gamma and TNF-alpha. CTLA4Ig treatment had no effect on IL-10 synthesis by T cells, a cytokine implicated in the functions of regulatory T cell subsets. Overall, our studies support the rationale of B7 blocking therapies as a potential treatment for models of multiple sclerosis. The induction of EAE in the Wistar rat provides yet another novel model in which to examine the regulation of T cell autoimmunity.


Asunto(s)
Antígeno B7-1/fisiología , Encefalomielitis Autoinmune Experimental/etiología , Inmunoconjugados , Proteína Básica de Mielina/inmunología , Linfocitos T/inmunología , Abatacept , Animales , Antígenos CD , Antígenos de Diferenciación/farmacología , Apoptosis , Autoanticuerpos/sangre , Encéfalo/patología , Antígeno CTLA-4 , Citocinas/biosíntesis , Encefalomielitis Autoinmune Experimental/inmunología , Encefalomielitis Autoinmune Experimental/patología , Ensayo de Inmunoadsorción Enzimática , Activación de Linfocitos , Ratas , Ratas Wistar , Receptores de Interleucina-2
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