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1.
Med Sci Monit ; 24: 687-697, 2018 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-29396390

RESUMEN

BACKGROUND This study analyzed the macular 3D-OCT images of Vogt-Koyanagi-Harada disease (VKH) in uveitis, explored the characteristics of 3D-OCT images of the macular region of VKH, and assessed which characteristics contribute most to VKH diagnosis. MATERIAL AND METHODS The 3D-OCT examination of 25 cases of VKH was performed on the macular area, and the image characteristics were analyzed. RESULTS Our study included a total of 50 eyes from 25 cases of VKH patients, 10 males and 15 females, aged 17 to 64 years, mean (39.44±11.60) years old. According to OCT B-scan images, 49 (98%) eyes had ERD, 49 (98%) eyes had nerve retinal edema, 36 (72%) eyes had endometrium-like structure (including cysts), 5 (10%) eyes had RPE folds, 35 (70%) eyes had changes in the internal septum, 49 (98%) eyes had RPE monolayer structure outside the ERD region. In ILM-RPE thickness, 49 (98%) eyes had retinal irregular thickening and 31 (62%) eyes had radial stripe changes. In ILM contour figure, 50 eyes (100%) showed exceptional uplift, 5 (10%) eyes had small focal uplift for PED on the RPE surface, and 48 (96%) eyes had wavy ups and downs. CONCLUSIONS In OCT B-scan imaging, the ERT, retinal edema of the retina, and the RPE monolayer structure outside the range are most likely to occur in VKH. The ILM-RPE thickness chart in 3D reconstruction showed irregular thickening of the retina. The ILM contour graph showed abnormal uplift, and RPE surface wavy ups and downs in VKH most likely to occur.


Asunto(s)
Imagenología Tridimensional , Tomografía de Coherencia Óptica , Uveítis/complicaciones , Uveítis/diagnóstico , Síndrome Uveomeningoencefálico/complicaciones , Síndrome Uveomeningoencefálico/diagnóstico , Adolescente , Adulto , Demografía , Femenino , Fondo de Ojo , Humanos , Mácula Lútea/patología , Masculino , Persona de Mediana Edad , Uveítis/fisiopatología , Síndrome Uveomeningoencefálico/fisiopatología , Agudeza Visual , Adulto Joven
2.
Curr Med Imaging ; 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37537936

RESUMEN

BACKGROUND: Spectral-Domain Optical Coherence Tomography (SD-OCT) provides non-invasive, high-speed, high-resolution, three-dimensional cross-section imaging of the macula. OBJECTIVES: This study aimed to investigate the diagnostic value of the multimodal imaging technique of three-dimension (3D) optical coherence tomography (OCT) (3D-OCT) for the diagnosis and characterization of acute central serous chorioretinopathy (CSC). METHODS: In this prospective clinical study 3D-OCT examinations of 82 cases with acute CSC were performed on the macular area, and the image characteristics were analyzed. Our study included a total of 87 eyes from 82 cases of CSC patients, 67 males and 15 females (mean age ± standard deviation (SD): 42.89 ±7.80 years old; age range: 27 to 56 years old. The 3D-OCT images were evaluated for the presence of subretinal fluid, subretinal space, fluctuation of the internal limiting membrane (ILM), folds of retinal pigment epithelial (RPE), retinal pigment epithelium detachment (PED), and flat irregular PED. The foveal thickness was measured using the manual caliper of OCT software. RESULTS: The OCT B-scan images showed 87 (100%) eyes had exudative retinal detachment (ERD), 38 (44%) had flat irregular PED, 36 (41%) had PED, 8 (9%) had subretinal turbidity structure, 2 (2%) had subretinal dot-like precipitates, 1 (1%) had focal choroidal excavation (FCE), and 1 (1%) eye had fluctuation of internal limiting membrane (FI). In the ILM-RPE thickness map, all eyes had a round or round like regular uniform domes. Fifty-seven (66%) domes were limited in the examination area and 30 (44%) domes were beyond the scope of this examination and only a partial section of the dome could be observed. In the en-face image, all eyes had a round or round-like black figure that corresponded with domes in the ILM-RPE thickness map. In RPE surface, 76 (87%) eyes had a shallow plate depression, 71(82%) had small focal uplift, and 1 (1%) eye had a focal concave feature. CONCLUSIONS: In the OCT ILM-RPE thickness, en-face image, and RPE surface maps, acute CSC exhibited specific imaging characteristics that can be helpful for reliable diagnosis and differential diagnosis of CSC.

3.
Chemistry ; 17(28): 7904-17, 2011 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-21611987

RESUMEN

The development, scope, and application of the highly enantioselective organocatalytic aziridination of α,ß-unsaturated aldehydes is presented. The aminocatalytic azirdination of α,ß-unsaturated aldehydes enables the asymmetric formation of ß-formyl aziridines with up to >19:1 d.r. and 99% ee. The aminocatalytic aziridination of α-monosubstituted enals gives access to terminal α-substituted-α-formyl aziridines in high yields and up to 99% ee. In the case of the organocatalytic aziridination of disubstituted α,ß-unsaturated aldehydes, the transformations were highly diastereo- and enantioselective and give nearly enantiomerically pure ß-formyl-functionalized aziridine products (99% ee). A highly enantioselective one-pot cascade sequence based on the combination of asymmetric amine and N-heterocyclic carbene catalysis (AHCC) is also disclosed. This one-pot three-component co-catalytic transformation between α,ß-unsaturated aldehydes, hydroxylamine derivatives, and alcohols gives the corresponding N-tert-butoxycarbonyl and N-carbobenzyloxy-protected ß-amino acid esters with ee values ranging from 92-99%. The mechanisms and stereochemistry of all these catalytic transformations are also discussed.

4.
Chemistry ; 16(5): 1585-91, 2010 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-20039352

RESUMEN

The first examples of one-pot highly chemo- and enantioselective dynamic kinetic asymmetric transformations (DYKATs) involving alpha,beta-unsaturated aldehydes and propargylated carbon acids are presented. These DYKATs, which proceed by a combination of catalytic iminium activation, enamine activation, and Pd(0)-catalyzed enyne cycloisomerization, give access to functionalized cyclopentenes with up to 99 % ee and can be used for the generation of all-carbon quaternary stereocenters.


Asunto(s)
Aminas/química , Ciclopentanos/síntesis química , Paladio/química , Elementos de Transición/síntesis química , Catálisis , Ciclización , Ciclopentanos/química , Cinética , Simulación de Dinámica Molecular , Estructura Molecular , Estereoisomerismo , Elementos de Transición/química
5.
Macromol Rapid Commun ; 31(8): 740-4, 2010 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-21590965

RESUMEN

A simple and direct method for derivatization of solid polysaccharides is presented. The novel methodology is based on the combination of organic acid-catalyzed esterification or etherification and photochemical thiol-ene click derivatization of a heterogeneous polysaccharide. The solid cellulose was "organoclick" modified with aryl, alkyl and polyester groups, respectively. The modification allows for a highly modular and metal free surface modification of solid polysaccharides.

6.
Chemistry ; 14(32): 10007-11, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18830983

RESUMEN

A highly enantioselective organocatalytic one-pot synthesis of nitro-, formyl-, and ester-functionalized cyclopentanes with four stereocenters is presented. The cyclopentanes were formed as a predominant diasteroisomer and isolated in high yields with 97-99 % ee.

7.
J Integr Plant Biol ; 50(9): 1130-9, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18844781

RESUMEN

The conserved domains of reverse transcriptase (RT) genes of Ty1-copia and Ty3-gypsy groups of long terminal repeat (LTR) retrotransposons were isolated from the Malus domestica genome using degenerate oligonucleotide primers. Sequence analysis showed that 45% of Ty1-copia and 63% of Ty3-gypsy RT sequences contained premature stop codons and/or indels disrupting the reading frame. High heterogeneity among RT sequences of both Ty1-copia and Ty3-gypsy group retrotransposons was observed, but Ty3-gypsy group retrotransposons in the apple genome are less heterogeneous than Ty1-copia elements. Retrotransposon copy number was estimated by dot blot hybridizations for Ty1-copia (approximately 5,000) and Ty3-gypsy (approximately 26,000). All elements of the two types of LTR retrotransposons comprise approximately 38% of the M. domestica genome, with the Ty3-gypsy group contribution being higher (33.5%) than the Ty1-copia one (4.6%). Transcription was not detected by reverse transcription-polymerase chain reaction for either Ty1-copia or Ty3-gypsy retrotransposons in the leaves of plants in vitro or in leaf explants cultured on medium supplemented with high concentration benzylaminopurine. This research reveals the differences in heterogeneity and copy number between Ty1-copia and Ty3-gypsy retrotransposons in the apple genome. Ty1-copia retrotransposon has higher heterogeneity than Ty3-gypsy retrotransposon, but the latter has a higher copy number, which implies that Ty3-gypsy retrotransposons may play a more important role in the apple genome evolution.


Asunto(s)
Dosificación de Gen , Genoma de Planta/genética , Malus/genética , Retroelementos/genética , Secuencias Repetidas Terminales/genética , Secuencia de Aminoácidos , Secuencia de Bases , ADN de Plantas/genética , ADN de Plantas/aislamiento & purificación , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Alineación de Secuencia , Transcripción Genética
8.
Chem Commun (Camb) ; (8): 849-51, 2007 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-17308652

RESUMEN

The highly chemo- and enantioselective organocatalytic tandem reaction between N-protected hydroxyl amines and alpha,beta-unsaturated aldehydes is presented; the reaction provides access to 5-hydroxyisoxazolidines and beta-amino acids in high yields and with 90-99% ee.


Asunto(s)
Aminoácidos/síntesis química , Oxazoles/química , Aldehídos/química , Catálisis , Cromatografía Líquida de Alta Presión , Indicadores y Reactivos , Conformación Molecular , Oxidación-Reducción , Estereoisomerismo
9.
Chem Commun (Camb) ; (7): 734-5, 2007 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-17392966

RESUMEN

The highly enantioselective direct organocatalytic conjugate addition of aldehydes to maleimides is presented.


Asunto(s)
Aldehídos/química , Maleimidas/química , Catálisis , Conformación Molecular , Estereoisomerismo , Succinimidas/síntesis química
13.
Org Lett ; 7(20): 4527-30, 2005 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-16178575

RESUMEN

[reaction: see text] DBU-catalyzed reactions of salicylic aldehydes with 3-methylpenta-3,4-dien-2-one, 3-benzylpenta-3,4-dien-2-one, or ethyl 2-methylbuta-2,3-dienoate gave the corresponding functionalized 2H-1-chromenes in good to excellent yields and good diastereoselectivities in some cases in DMSO, respectively.


Asunto(s)
Aldehídos/química , Benzopiranos/química , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Ésteres/química , Cetonas/química , Benzopiranos/síntesis química , Catálisis , Cristalografía por Rayos X , Modelos Moleculares , Estructura Molecular
14.
Free Radic Biol Med ; 37(6): 823-38, 2004 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-15384203

RESUMEN

Transiently local release of Ca(2+) from the sarcoplasmic reticulum (SR) activates nearby Ca(2+)-activated K(+) channels to produce spontaneous transient outward currents (STOCs) in smooth muscle cells. The purpose of the present study was to investigate the possible effect of peroxynitrite (ONOO(-)) on STOCs in mesenteric arteriolar smooth muscle cells (ASMCs) and decide whether Ca(2+) mobilization was involved in STOCs alteration by ONOO(-). STOCs were recorded and characterized using the perforated whole-cell patch-clamp configuration. The results demonstrated that STOCs activity was greatly suppressed by removal of extracellular Ca(2+); by addition of nifedipine, a specific inhibitor of L-type voltage-gated Ca(2+) channels (VGCCs); or by addition of ryanodine, a SR ryanodine receptors (RyRs) blocker. In contrast, both caffeine, a RyR activator, and 2-aminoethoxydiphenylborate (2-APB), a membrane-permeable inositol 1,4,5-trisphosphate receptors, (IP3R) antagonist, increased STOCs activity. 3-morpholinosydnonimine (SIN-1), an ONOO(-) donor, at concentrations of 20-200 microM, induced a dose-dependent enhancement of STOCs in ASMCs and led to conspicuous increases in STOCs frequency and amplitude, which were prevented by prior exposure to low external Ca(2+) (200 nM), ryanodine (10 microM), or nifedipine (10 microM). In contrast, caffeine (0.5 mM) did not further stimulate STOCs in ASMCs preincubated with SIN-1, and pretreatment with 2-APB (50 microM) had little effect on ONOO(-) -induced STOCs activation. These findings suggest that complex Ca(2+)-mobilizing pathways, including external Ca2+ influx through VGCCs activation and subsequent internal Ca(2+) release through RyRs but not IP3Rs, are involved in ONOO(-)mediated STOCs enhancement in ASMCs.


Asunto(s)
Calcio/metabolismo , Molsidomina/análogos & derivados , Miocitos del Músculo Liso/metabolismo , Ácido Peroxinitroso/farmacología , Animales , Compuestos de Boro/farmacología , Cafeína/farmacología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Electrofisiología , Femenino , Masculino , Potenciales de la Membrana , Modelos Biológicos , Molsidomina/farmacología , Músculo Liso/citología , Miocitos del Músculo Liso/citología , Nifedipino/farmacología , Técnicas de Placa-Clamp , Ácido Peroxinitroso/química , Potasio/química , Ratas , Ratas Wistar , Rianodina/metabolismo , Rianodina/farmacología , Transducción de Señal , Factores de Tiempo
16.
Org Lett ; 5(24): 4737-9, 2003 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-14627428

RESUMEN

[reaction: see text] The attempted aza-Baylis-Hillman reaction of N-tosylated imines with ethyl 2,3-butadienoate or penta-3,4-dien-2-one gave azetidine derivatives in the presence of DABCO. In the case of the aza-Baylis-Hillman reaction of N-tosylated imines with ethyl 2,3-butandieonate catalyzed by DMAP, novel dihydropyridine derivatives were formed.

17.
Life Sci ; 74(10): 1199-210, 2004 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-14697404

RESUMEN

Peroxynitrite (ONOO-) has been recently known to act as a potent cytotoxin during pathogenesis of various diseases. This study aimed to investigate the possible effect of ONOO- on the cremaster muscle arteriolar reactivity in response to noradrenaline and subsequently determined whether membrane hyperpolarization and potassium channel activation were involved in ONOO(-)-induced alteration of arteriolar reactivity. The results demonstrated that 1) ONOO- could decrease arteriolar reactivity in a time- and concentration-dependent manner with no significant alteration of arteriolar diameter; 2) Superfusion with 20 microM ONOO- over 40 minutes showed slight but not significant influence on the resting potential (Em) of arteriolar smooth muscle cells (ASMCs). However, ASMCs subjected to 50 or 100 microM ONOO- administration were significantly hyperpolarized. As control, treatment with 50 microM decomposed ONOO- or Kreb's solution had little effect on the Em of ASMCs; 3) ONOO(-)-induced arteriolar hyporeactivity could be greatly reversed by co-administration of KCl and partially by TEA. The above results indicated that membrane hyperpolarization and potassium channel activation were preferentially responsible for the reduction of cremaster muscle arteriolar reactivity after exposure to ONOO-.


Asunto(s)
Músculo Liso Vascular/efectos de los fármacos , Ácido Peroxinitroso/farmacología , Animales , Arteriolas/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Membrana Celular/fisiología , Colorantes , Técnicas In Vitro , Indicadores y Reactivos , Masculino , Potenciales de la Membrana/efectos de los fármacos , Músculo Liso Vascular/citología , Oxidación-Reducción , Cloruro de Potasio/farmacología , Ratas , Ratas Sprague-Dawley , Tetraetilamonio/farmacología
18.
Redox Rep ; 9(1): 49-55, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15035827

RESUMEN

The present study was designed to investigate the possible effects of peroxynitrite (ONOO(-)) on the intracellular calcium concentration ([Ca(2+)](i)) of mesenteric arteriolar smooth muscle cells (ASMCs), and to reveal the underlying mechanisms by using fluorescence imaging analysis. The results showed that ONOO(-) could exert a concentration- and time-dependent but also a dual effect on [Ca(2+)](i). Bolus administration with a low concentration of ONOO(-) (25 microM) decreased [Ca(2+)](i), whereas higher concentrations (50 or 100 microM) increased [Ca(2+)](i) persistently. Further experiments demonstrated that pretreatment of ASMCs with calcium-free medium completely abolished [Ca(2+)](i) increase by 100 microM ONOO(-). Additionally, nifedipine, an antagonist of selective L-type voltage-gated calcium channels (VGCCs), delayed the [Ca(2+)](i) response to ONOO(-), and ryanodine, an inhibitor of intracellular calcium release from the sarcoplasmic reticulum, effectively antagonized [Ca(2+)](i) increase during the late stage of ONOO(-) exposure. Furthermore, [Ca(2+)](i) alteration by ONOO(-) appeared to be intimately associated with the subsequent membrane potential changes. Although the mechanisms by which ONOO(-) alters [Ca(2+)](i) are complex, we conclude that a series of variables such as external calcium influx, activation of VGCCs, intracellular calcium release, and membrane potential changes are involved. The decrease of [Ca(2+)](i) in ASMCs by a low concentration of ONOO(-) may participate in the pathogenesis of low vasoreactivity in shock, and the increase of [Ca(2+)](i) by high concentrations of ONOO(-) may lead to calcium overload with cellular injury.


Asunto(s)
Arteriolas/citología , Calcio/metabolismo , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/metabolismo , Ácido Peroxinitroso/farmacología , Animales , Calcio/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Nifedipino/farmacología , Ácido Peroxinitroso/agonistas , Ácido Peroxinitroso/antagonistas & inhibidores , Ratas , Ratas Wistar , Rianodina/farmacología , Factores de Tiempo
19.
Di Yi Jun Yi Da Xue Xue Bao ; 24(2): 144-7, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14965811

RESUMEN

OBJECTIVE: To investigate the effect of SOD and NaHCO3 on the vascular hyporeactivity after severe hemorrhagic shock in rats. METHODS: Twenty eight Sprague-Dawley rats were divided randomly into 4 groups of 7 each: SOD-treated group, NaHCO3-treated group, SOD+NaHCO3-treated group and normal saline-treated control group. The responses of arterioles to norepinephrine (NE), the effects of dopamine on blood pressure, blood flow velocity in arterioles, the mean arterial pressure (MAP), and the survival time within 24 h were measured. RESULTS: Two hours after shock, the arteriolar vasoreactivity was significantly reduced and threshold concentration of NE was increased by 24 to 27 folds. After beting treated separately with SOD, NaHCO3 and SOD+NaHCO3, arteriolar vasoreactivity was restored to some extent, among which the SOD+NaHCO3 group obtained a most significant effect with decreased threshold concentration of NE to 21% of its normal level. In SOD+NaHCO3-treated group, injection of dopamine indicated a most significant effect on MAP with 1.9 times more than that in control group, and the enhanced MAP was maintained at a level of more than 13.33 kPa after reinfusion of shed blood. The blood flow in arteriole was 2.54-fold higher than that in control group after 2 h resuscitation. The average survival time in SOD+NaHCO3- treated group was 2.9 times longer than that in control group. CONCLUSIONS: SOD and NaHCO3 could both recover the lower vasoreactivity and increase the enhancing effect of dopamine on blood pressure of rats in severe hemorrhagic shock, suggesting that coadministration of SOD and NaHCO3 could be a new approach to the treatment of severe hemorrhagic shock.


Asunto(s)
Choque Hemorrágico/tratamiento farmacológico , Bicarbonato de Sodio/farmacología , Superóxido Dismutasa/farmacología , Animales , Presión Sanguínea/efectos de los fármacos , Dopamina/farmacología , Quimioterapia Combinada , Ratas , Ratas Sprague-Dawley , Flujo Sanguíneo Regional/efectos de los fármacos , Choque Hemorrágico/fisiopatología , Bicarbonato de Sodio/administración & dosificación , Superóxido Dismutasa/administración & dosificación
20.
Di Yi Jun Yi Da Xue Xue Bao ; 23(8): 786-90, 2003 Aug.
Artículo en Zh | MEDLINE | ID: mdl-12919898

RESUMEN

OBJECTIVE: To investigate the electrophysiological properties of large-conductance calcium-activated potassium channel (BKCa) in mesenteric arteriole smooth muscle cells of rat. METHOD: Mesenteric arteriolar smooth muscle cells from rats were isolated and inside-out patch clamp technique was used to study BKCa. RESULTS: The single channel conductance of BKCa recorded was 221+/-6 pS and the reversal potential was -0.12 mV in the presence of high potassium in the bathing and pipette solutions. The open probability (NPo) of the channel was both voltage- and intracellular calcium dependent, whereas the amplitude of the channel was not calcium-dependent. Prolonged closed state could be observed at intracellular calcium concentrations of 1 micromol/L or above, known as calcium-dependent inactivation. CONCLUSION: BKCa in rat mesenteric arterial smooth muscle cells has the properties of large conductance, high potassium selectivity, steep voltage dependence and high calcium sensitivity. The high sensitivity to calcium of BKCa may be related to the compensatory regulation of the smooth muscles in pathophysiological conditions.


Asunto(s)
Arterias Mesentéricas/metabolismo , Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/metabolismo , Canales de Potasio Calcio-Activados/fisiología , Animales , Femenino , Masculino , Potenciales de la Membrana , Arterias Mesentéricas/citología , Músculo Liso Vascular/citología , Ratas , Ratas Wistar
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