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1.
Biochim Biophys Acta ; 1850(7): 1389-96, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25857772

RESUMEN

BACKGROUND: Melanogenesis, a process producing the pigment melanin in human skin, eyes and hair, is a major physiological response against various environmental stresses, in particular exposure to ultraviolet radiation, and its pathway is regulated by a key enzyme, tyrosinase. In this study, we evaluated the effects of ephedrannins A and B, which are polyphenols from the roots of Ephedra sinica, commonly used in herbalism in oriental countries, on mushroom tyrosinase and melanogenesis in B16F10 melanoma cells. METHODS: Their effects on mushroom tyrosinase were determined via kinetic studies using a spectrophotometric analysis and those on melanin and tyrosinase production in melanoma cells treated with α-MSH (melanin stimulating hormone) were examined using PCR and ELISA. RESULTS: Both ephedrannins A and B exhibited concentration-dependent inhibitory effects on L-tyrosine oxidation by mushroom tyrosinase, and the inhibition mechanism was competitive and reversible with L-tyrosine as the substrate. In addition, melanin production in melanoma cells was also suppressed in a concentration-dependent manner by ephedrannins A and B without significant effects on cell proliferation at the concentrations tested. Both compounds showed inhibitory effects on melanin production by suppressing the transcription of tyrosinase in the cells. CONCLUSION: Both compounds exhibited significant inhibitory effects, but the inhibition by ephedrannin B was much more effective than that by ephedrannin A. Both ephedrannins A and B may be good candidates for a whitening agent for skin. GENERAL SIGNIFICANCE: This is the first report that describes effective inhibition of melanin production by ephedrannins A and B isolated from Ephedra roots.


Asunto(s)
Ephedra sinica/química , Melaninas/biosíntesis , Monofenol Monooxigenasa/metabolismo , Raíces de Plantas/química , Proantocianidinas/farmacología , Animales , Biocatálisis/efectos de los fármacos , Western Blotting , Línea Celular , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Humanos , Queratinocitos/citología , Queratinocitos/efectos de los fármacos , Cinética , Ratones , Estructura Molecular , Monofenol Monooxigenasa/genética , Extractos Vegetales/farmacología , Proantocianidinas/química , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Especificidad por Sustrato , Tirosina/metabolismo
2.
PLoS Pathog ; 9(10): e1003646, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24098117

RESUMEN

Thioredoxin-interacting protein (TXNIP) has multiple functions, including tumor suppression and involvement in cell proliferation and apoptosis. However, its role in the inflammatory process remains unclear. In this report, we demonstrate that Txnip⁻/⁻ mice are significantly more susceptible to lipopolysaccharide (LPS)-induced endotoxic shock. In response to LPS, Txnip⁻/⁻ macrophages produced significantly higher levels of nitric oxide (NO) and inducible nitric oxide synthase (iNOS), and an iNOS inhibitor rescued Txnip⁻/⁻ mice from endotoxic shock-induced death, demonstrating that NO is a major factor in TXNIP-mediated endotoxic shock. This susceptibility phenotype of Txnip⁻/⁻ mice occurred despite reduced IL-1ß secretion due to increased S-nitrosylation of NLRP3 compared to wild-type controls. Taken together, these data demonstrate that TXNIP is a novel molecule that links NO synthesis and NLRP3 inflammasome activation during endotoxic shock.


Asunto(s)
Proteínas Portadoras/metabolismo , Inflamasomas/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Óxido Nítrico/metabolismo , Choque Séptico/metabolismo , Tiorredoxinas/metabolismo , Animales , Proteínas Portadoras/genética , Inflamasomas/genética , Lipopolisacáridos/toxicidad , Ratones , Ratones Noqueados , Proteína con Dominio Pirina 3 de la Familia NLR , Óxido Nítrico/genética , Óxido Nítrico Sintasa de Tipo II/genética , Choque Séptico/inducido químicamente , Choque Séptico/genética , Tiorredoxinas/genética
3.
Biochim Biophys Acta ; 1800(11): 1164-72, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20655986

RESUMEN

BACKGROUND: Dienelactone hydrolases catalyze the hydrolysis of dienelactone to maleylacetate, which play a key role for the microbial degradation of chloroaromatics via chlorocatechols. Here, a thermostable dienelactone hydrolase from thermoacidophilic archaeon Sulfolobus solfataricus P1 was the first purified and characterized and then expressed in Escherichia coli. METHODS: The enzyme was purified by using several column chromatographys and characterized by determining the enzyme activity using p-nitrophenyl caprylate and dienelactones. In addition, the amino acids related to the catalytic mechanism were examined by site-directed mutagenesis using the identified gene. RESULTS: The enzyme, approximately 29 kDa monomeric, showed the maximal activity at 74 degrees C and pH 5.0, respectively. The enzyme displayed remarkable thermostability: it retained approximately 50% of its activity after 50 h of incubation at 90 degrees C, and showed high stability against denaturing agents, including various detergents, urea, and organic solvents. The enzyme displayed substrate specificities toward trans-dienelactone, not cis-isomer, and also carboxylesterase activity toward p-nitrophenyl esters ranging from butyrate (C4) to laurate (C12). The k(cat)/K(m) ratios for trans-dienelactone and p-nitrophenyl caprylate (C8), the best substrate, were 92.5 and 54.7 s⁻¹ µM⁻¹, respectively. CONCLUSIONS: The enzyme is a typical dienelactone hydrolase belonging to alpha/beta hydrolase family and containing a catalytic triad composed of Cys151, Asp198, and His229 in the active site. GENERAL SIGNIFICANCE: The enzyme is the first characterized archaeal dienelactone hydrolase.


Asunto(s)
Hidrolasas de Éster Carboxílico/aislamiento & purificación , Hidrolasas de Éster Carboxílico/metabolismo , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Sulfolobus solfataricus/enzimología , Secuencia de Aminoácidos , Hidrolasas de Éster Carboxílico/genética , Catálisis , Clonación Molecular , Cinética , Datos de Secuencia Molecular , Peso Molecular , Mutagénesis Sitio-Dirigida , Proteínas Recombinantes/genética , Sulfolobus solfataricus/genética , Temperatura
4.
J Bacteriol ; 190(24): 8086-95, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18931117

RESUMEN

A novel thermostable arylesterase, a 35-kDa monomeric enzyme, was purified from the thermoacidophilic archaeon Sulfolobus solfataricus P1. The optimum temperature and pH were 94 degrees C and 7.0, respectively. The enzyme displayed remarkable thermostability: it retained 52% of its activity after 50 h of incubation at 90 degrees C. In addition, the purified enzyme showed high stability against denaturing agents, including various detergents, urea, and organic solvents. The enzyme has broad substrate specificity besides showing an arylesterase activity toward aromatic esters: it exhibits not only carboxylesterase activity toward tributyrin and p-nitrophenyl esters containing unsubstituted fatty acids from butyrate (C(4)) to palmitate (C(16)), but also paraoxonase activity toward organophosphates such as p-nitrophenylphosphate, paraoxon, and methylparaoxon. The k(cat)/K(m) ratios of the enzyme for phenyl acetate and paraoxon, the two most preferable substrates among all tested, were 30.6 and 119.4 s(-1) microM(-1), respectively. The arylesterase gene consists of 918 bp corresponding to 306 amino acid residues. The deduced amino acid sequence shares 34% identity with that of arylesterase from Acinetobacter sp. strain ADP1. Furthermore, we successfully expressed active recombinant S. solfataricus arylesterase in Escherichia coli. Together, our results show that the enzyme is a serine esterase belonging to the A-esterases and contains a catalytic triad composed of Ser156, Asp251, and His281 in the active site.


Asunto(s)
Proteínas Arqueales/metabolismo , Hidrolasas de Éster Carboxílico/metabolismo , Sulfolobus solfataricus/enzimología , Secuencia de Aminoácidos , Proteínas Arqueales/genética , Proteínas Arqueales/aislamiento & purificación , Hidrolasas de Éster Carboxílico/genética , Hidrolasas de Éster Carboxílico/aislamiento & purificación , Clonación Molecular , ADN de Archaea/genética , Estabilidad de Enzimas , Genes Arqueales , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Peso Molecular , Alineación de Secuencia , Especificidad por Sustrato , Sulfolobus solfataricus/genética , Temperatura
5.
J Org Chem ; 73(20): 8106-8, 2008 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-18808183

RESUMEN

Careful examination of nucleophilicity, basicity, and leaving group ability led us to discover the nucleophilic fluorination of triflates by weakly basic tetrabutylammonium bifluoride, which provides excellent yields with minimal formation of elimination-derived side products. Primary hydroxyl groups as well as secondary hydroxyl groups in acyclic chains or in five-membered rings are excellent substrates, whereas benzylic and aldol-type secondary hydroxyl groups give poor yields as a result of the instability of their triflates.


Asunto(s)
Compuestos de Amonio Cuaternario/química , Química Orgánica/métodos , Flúor/química , Halogenación
6.
Biochim Biophys Acta ; 1760(5): 820-8, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16574328

RESUMEN

The carboxylesterase, a 34 kDa monomeric enzyme, was purified from the thermoacidophilic archaeon Sulfolobus solfataricus P1. The optimum temperature and pH were 85 degrees C and 8.0, respectively. The enzyme showed remarkable thermostability: 41% of its activity remained after 5 days of incubation at 80 degrees C. In addition, the purified enzyme exhibited stability against denaturing agents, including various detergents, urea, and organic solvents. The enzyme has broad substrate specificity towards various PNP esters and short acyl chain triacylglycerols such as tributyrin (C4:0). Among the PNP esters tested, the best substrate was PNP-caprylate (C8) with Km and kcat values of 71 microM and 14,700 s(-1), respectively. The carboxylesterase gene consisted of 915 bp corresponding to 305 amino acid residues. We demonstrated that active recombinant S. solfataricus carboxylesterase could be expressed in Escherichia coli. The enzyme was identified as a serine esterase belonging to mammalian hormone-sensitive lipases (HSL) family and contained a catalytic triad composed of serine, histidine, and aspartic acid in the active site.


Asunto(s)
Proteínas Arqueales/química , Carboxilesterasa/química , Calor , Sulfolobus solfataricus/enzimología , Secuencia de Aminoácidos , Proteínas Arqueales/biosíntesis , Proteínas Arqueales/aislamiento & purificación , Secuencia de Bases , Carboxilesterasa/biosíntesis , Carboxilesterasa/aislamiento & purificación , Catálisis , Clonación Molecular , Estabilidad de Enzimas , Escherichia coli/enzimología , Escherichia coli/genética , Datos de Secuencia Molecular , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación , Especificidad por Sustrato
7.
J Biochem Mol Biol ; 39(1): 46-54, 2006 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-16466637

RESUMEN

The coenzyme A-acylating 2-oxoacid:ferredoxin oxidoreductase and ferredoxin (an effective electron acceptor) were purified from the hyperthermophilic archaeon, Sulfolobus solfataricus P1 (DSM1616). The purified ferredoxin is a monomeric protein with an apparent molecular mass of approximately 11 kDa by SDS-PAGE and of 11,180+/-50 Da by MALDI-TOF mass spectrometry. Ferredoxin was identified to be a dicluster, [3Fe-4S][4Fe-4S], type ferredoxin by spectrophotometric and EPR studies, and appeared to be zinc-containing based on the shared homology of its N-terminal sequence with those of known zinc-containing ferredoxins. On the other hand, the purified 2-oxoacid: ferredoxin oxidoreductase was found to be a heterodimeric enzyme consisting of 69 kDa alpha and 34 kDa beta subunits by SDS-PAGE and MALDI-TOF mass spectrometry. The purified enzyme showed a specific activity of 52.6 units/mg for the reduction of cytochrome c with 2-oxoglutarate as substrate at 55 degrees C, pH 7.0. Maximum activity was observed at 70 degrees C and the optimum pH for enzymatic activity was 7.0 -8.0. The enzyme displays broad substrate specificity toward 2-oxoacids, such as pyruvate, 2-oxobutyrate, and 2-oxoglutarate. Among the 2-oxoacids tested (pyruvate, 2-oxobutyrate, and 2-oxoglutarate), 2-oxoglutarate was found to be the best substrate with Km and kcat values of 163 microM and 452 min(-1), respectively. These results provide useful information for structural studies on these two proteins and for studies on the mechanism of electron transfer between the two.


Asunto(s)
Proteínas Arqueales , Ferredoxinas , Piruvato-Sintasa , Sulfolobus solfataricus , Secuencia de Aminoácidos , Proteínas Arqueales/química , Proteínas Arqueales/genética , Proteínas Arqueales/aislamiento & purificación , Proteínas Arqueales/metabolismo , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Peso Molecular , Piruvato-Sintasa/química , Piruvato-Sintasa/genética , Piruvato-Sintasa/aislamiento & purificación , Piruvato-Sintasa/metabolismo , Homología de Secuencia de Aminoácido , Especificidad por Sustrato , Sulfolobus solfataricus/química , Sulfolobus solfataricus/enzimología , Temperatura
8.
BMB Rep ; 49(6): 349-54, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27222124

RESUMEN

The archaeon Sulfolobus solfataricus P1 carboxylesterase is a thermostable enzyme with a molecular mass of 33.5 kDa belonging to the mammalian hormone-sensitive lipase (HSL) family. In our previous study, we purified the enzyme and suggested the expected amino acids related to its catalysis by chemical modification and a sequence homology search. For further validating these amino acids in this study, we modified them using site-directed mutagenesis and examined the activity of the mutant enzymes using spectrophotometric analysis and then estimated by homology modeling and fluorescence analysis. As a result, it was identified that Ser151, Asp244, and His274 consist of a catalytic triad, and Gly80, Gly81, and Ala152 compose an oxyanion hole of the enzyme. In addition, it was also determined that the cysteine residues are located near the active site or at the positions inducing any conformational changes of the enzyme by their replacement with serine residues. [BMB Reports 2016; 49(6): 349-354].


Asunto(s)
Aminoácidos/metabolismo , Biocatálisis , Carboxilesterasa/química , Carboxilesterasa/metabolismo , Modelos Moleculares , Mutagénesis Sitio-Dirigida , Sulfolobus solfataricus/enzimología , Secuencia de Aminoácidos , Carboxilesterasa/genética , Cisteína/metabolismo , Fluorescencia , Proteínas Mutantes/química , Proteínas Mutantes/aislamiento & purificación , Mutación/genética , Plásmidos/metabolismo , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Homología Estructural de Proteína , Relación Estructura-Actividad
9.
J Dermatol ; 39(3): 295-300, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22035317

RESUMEN

People with sensitive skin (SS) are those who state their skin is more sensitive than that of average persons. The stratum corneum is responsible for maintaining skin barrier function. Ceramides, major constituents of stratum corneum lipids, have been shown to predominantly contribute to the role. It has been suggested that barrier function in SS is decreased. However, we could find very few reports about stratum corneum ceramides in SS. This study was done to find out differences in stratum corneum ceramides between SS and non-SS groups. Fifty individuals (20 with SS and 30 with non-SS) were recruited. Lactic acid sting test (LAST) was performed on the left cheek. On six sites including the right cheek, arm, thigh, leg, back and palm, transepidermal water loss (TEWL) and erythema index (EI) were measured. On the above six sites, stratum corneum sheets were obtained by stripping with cyanoacrylate resin and stratum corneum lipids were extracted, then, analyzed by high-performance liquid chromatography electrospray ionization mass spectrometry. LAST scores were higher in the SS group, but not statistically significant. There were no differences in TEWL and EI values between the two groups. The mean value of the quantity of stratum corneum ceramides on the face was significantly lower in the SS group. On other sites, mean values were also lower in the SS group, but not statistically significant. The quantity of ceramides was significantly decreased in the face of the SS group compared to that of the non-SS group. These results suggest that the decrease in stratum corneum ceramides on facial skin could be related to SS development.


Asunto(s)
Ceramidas/análisis , Piel/química , Adulto , Dorso , Eritema/inducido químicamente , Cara , Femenino , Antebrazo , Mano , Humanos , Ácido Láctico , Pierna , Masculino , Dolor/inducido químicamente , Muslo , Pérdida Insensible de Agua , Adulto Joven
10.
Ann Dermatol ; 23 Suppl 1: S116-8, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22028556

RESUMEN

Subepidermal calcified nodule is an uncommon form of calcinosis cutis, which most commonly occurs in children. It usually presents as an asymptomatic, solitary verrucous nodule on the head and neck region, but occasionally as multiple lesions. Serum calcium and phosphorus levels are usually normal. Histopathology shows well-formed homogeneous eosinophilic material and granules in the upper dermis. Material in the dermis stained with von Kossa was positive. We report on an unusual case of a subepidermal calcified nodule occurring on the sole. A 21-month-old male presented with an oval-shaped, whitish, hard nodule measuring 5×5 mm on the left sole, without any previous history of trauma.

11.
Ann Dermatol ; 23 Suppl 1: S91-5, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22028584

RESUMEN

Atopic dermatitis (AD) has numerous trigger factors. The question of whether foods can aggravate AD remains open to debate. Although a number of published papers have detailed the relationship between food allergies and AD, little research has examined the question of how food intolerance affects AD. For the purposes of this study, a six-year-old Korean boy with AD was admitted to the hospital for evaluation of the possibility of food, particularly pork, as a triggering factor in his skin disease. He had a history of worsening of symptoms when eating pork. Total serum IgE concentration was 157 IU/ml. House dust was class 2.2 (1.5 IU/ml) in MAST. All other MAST items were negative. In an oral food challenge test, he showed a positive result after eating 200 g of pork, but did not show a positive result after eating 60 g of pork. After discharge, we attempted to keep him on a balanced diet that included various types of food and prohibited him from eating food that contains a high level of histamine. After keeping the patient on a balanced and low-histamine dietary regimen, his AD symptoms showed improvement and have not worsened for more than seven months. A low-histamine, balanced diet could be helpful for AD patients having symptoms that resemble histamine intolerance in which their AD symptoms worsened after intake of histamine-rich foods, but in which food allergy tests are negative.

12.
Int Immunopharmacol ; 10(12): 1616-25, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20939997

RESUMEN

Ephedra sinica is a traditional Chinese medicinal herb and has pharmacological functions including anti-inflammatory effects. However, the active ingredients from Ephedra roots have not been characterized. Here, two active constituents were isolated and their structures and mechanisms of action were defined. Active constituents from Ephedra roots were isolated by continuous solvent-extractions and column chromatography. Their structures were determined by use of multiple types of spectrometry. The mechanisms of action were examined using lipopolysaccharide (LPS)-stimulated RAW 264.7 cells through PCR, ELISA, electrophoretic mobility shift assays, and immunocytochemistry. Two active constituents, ephedrannin A and B, belonging to the A-type proanthocyanidin family were identified. Both ephedrannin A and B effectively suppressed the transcription of tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß). These compounds exerted their anti-inflammatory actions on LPS-stimulated macrophages by suppressing the translocation of nuclear factor-kappa B (NF-κB) and the phosphorylation of p38 mitogen-activated protein (MAP) kinase. Ephedrannin A and B both exhibited strong anti-inflammatory effects, however, the optimal dose of ephedrannin B was 10 times lower than that of ephedrannin A. This is the first report describing effective anti-inflammatory activity for ephedrannin A and B isolated from Ephedra roots. Ephedrannin B may be a good candidate for delaying the progression of human inflammatory diseases and warrants further studies.


Asunto(s)
Antiinflamatorios/farmacología , Ephedra sinica/química , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , FN-kappa B/antagonistas & inhibidores , Proantocianidinas/farmacología , Animales , Antiinflamatorios/aislamiento & purificación , Western Blotting , Línea Celular , Ensayo de Cambio de Movilidad Electroforética , Expresión Génica/efectos de los fármacos , Inmunohistoquímica , Interleucina-1/antagonistas & inhibidores , Macrófagos/metabolismo , Ratones , Estructura Molecular , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico Sintasa de Tipo II/antagonistas & inhibidores , Óxido Nítrico Sintasa de Tipo II/genética , Raíces de Plantas/química , Proantocianidinas/aislamiento & purificación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de Transcripción ReIA/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores
13.
Ann Dermatol ; 21(1): 66-70, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20548861

RESUMEN

Congenital leukemia is a rare disease that develops from birth to 6 weeks of life. Leukemia cutis involves cutaneous infiltration by leukemic cells and is an unusual manifestation of leukemia, and has been documented in 25~30% of patients with congenital leukemia. The authors report a case of congenital leukemia cutis. A newborn male presented with widespread firm dusky red papules and nodules on almost his entire body surface. Skin biopsy specimens confirmed the presence of leukemic infiltrations, and bone marrow cytology was consistent with acute myeloid leukemia of the FAB M5 type.

14.
Ann Dermatol ; 21(2): 203-5, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-20523788

RESUMEN

Food-dependent, exercise-induced anaphylaxis (FDEIA) is the triggering of anaphylaxis after ingestion of certain foods when followed by physical exercise. Symptoms vary from the typical generalized urticaria to severe allergic reactions. We report the case of a 20-year-old woman who had a 7-year history of recurrent wheals and dyspnea after ingesting several kinds of food (wheat, pork, and beef) along with physical exercise. Based on a provocation test, she was diagnosed with wheat-dependent, exercise-induced anaphylaxis. She was instructed to take 2 mg of ketotifen 2 hours before ingestion of wheat to prevent the symptoms, and subsequently the provocation test did not elicit wheals. We therefore prescribed ketotifen (1 mg twice a day). She has not had recurrent wheals or dyspnea for 6 months. We herein report an interesting case of wheat-dependent, exercise-induced anaphylaxis with successful prevention by ketotifen.

15.
Ann Dermatol ; 21(2): 213-6, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-20523791

RESUMEN

Churg-Strauss syndrome (CSS) or allergic granulomatosis angiitis is a rare primary vasculitic disease. CSS can be diagnosed by the presence of any four or more of the six criteria, which include asthma, eosinophilia greater than 10%, paranasal sinusitis, pulmonary infiltration, histological proof of vasculitis and mono- or poly-neuropathy. We report here on a 45-year-old male who developed erythematous macules, papules and hemorrhagic vesicles on both right extremities along with a tingling sensation and sacral pain. He has been suffering from recurrent allergic rhinitis and bronchial asthma for 6 months. The laboratory findings showed severe eosinophilia (22.3%), hyper-IgE and positivity for p-ANCA. On the histological examination of the hemorrhagic vesicle on the right lower leg, leukocytoclsatic vasulitis and many neutrophils and eosinophils around the cutaneous vessels were observed in the dermis.

16.
Ann Dermatol ; 21(4): 447-9, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20523846

RESUMEN

Foods are recognized as a common cause of urticaria; however, the role of food is considered to be more important in acute not chronic urticaria. Wheat is a basic ingredient found in many common foods. Food allergy to wheat is primarily described in children in the form of atopic dermatitis. It is rare in adults; where it is mainly reported in exercise-induced anaphylaxis. We report a case of wheat dependent exercise-induced anaphylaxis that occurred in a 54-year-old Korean woman.

17.
Bioresour Technol ; 100(23): 6107-13, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19608415

RESUMEN

Recent studies suggest that olive leaf is a significant source of bioactive phenolic compounds comparable to olive oil and fruits. Identifying appropriate extraction methods is thus an important step to increase the yield of such bioactive components from olive leaf, which is otherwise agricultural waste. The present study evaluates phenolic contents and compositions of olive leaf extracted by several solvent methods and to further establish their antioxidant activities using various radical scavenging systems. Total flavonoid and phenolic contents were significantly higher in the 80% ethanol extract, butanol, and ethylacetate fractions than hexane, chloroform and water fractions (p<0.05). Oleuropein was identified as a major phenolic compound with considerable contents in these major three fractions and the extract that correlated with their higher antioxidant and radical scavenging. These results indicate that olive leaf contains significant amounts of oleuropein and phenolics, important factors for antioxidant capacity, which can be substantially modified by different extraction methods.


Asunto(s)
Antioxidantes/metabolismo , Olea/metabolismo , Fenoles/química , Extractos Vegetales/farmacología , Agricultura/métodos , Antioxidantes/química , Cloroformo/química , Depuradores de Radicales Libres , Hexanos/química , Residuos Industriales , Glucósidos Iridoides , Iridoides , Ácido Linoleico/química , Oxígeno/química , Peróxidos/química , Fenol , Piranos/química , Agua/química
18.
J Org Chem ; 72(26): 10261-3, 2007 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-18047371

RESUMEN

Reaction of aryl nitriles with potassium ethyl malonate in the presence of zinc chloride and a catalytic amount of Hünig's base provided beta-amino acrylates in moderate to good yield. Compared to the classical Blaise reaction, this reaction is safer (endothermic), devoid of lacrimatory reagent, and is possible with 0.5-1.0 equiv of zinc chloride.


Asunto(s)
Acrilatos/síntesis química , Nitrilos/química , Acrilatos/química , Catálisis , Cloruros/química , Descarboxilación , Malonatos/química , Estructura Molecular , Potasio/química , Solventes/química , Compuestos de Zinc/química
19.
J Org Chem ; 68(6): 2205-8, 2003 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-12636382

RESUMEN

Starting with the tricyclic core 2b, annulation to form the 13-membered western ring of sarain A has been achieved to afford the macrocycle 30a by initial construction of the sterically congested quaternary center at C-3, followed by elaboration of the C-3 side-chain and ring-closing olefin metathesis. Also included is a parallel conversion of tricycle 2c to macrocycle 30b containing a functionalized side-chain at N-1 suitable for attachment of the eastern macrocyclic ring.


Asunto(s)
Alcaloides/síntesis química , Hidrocarburos Aromáticos con Puentes/síntesis química , Hidrocarburos Policíclicos Aromáticos/síntesis química , Animales , Catálisis , Ciclización , Indicadores y Reactivos , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Poríferos/química , Relación Estructura-Actividad
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