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1.
Am J Ophthalmol ; 264: 205-215, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-38522724

RESUMEN

PURPOSE: To describe the clinical and genetic features, and explore the natural history of retinopathy associated with IQCB1 variants in children and adults with retinopathy. DESIGN: Retrospective cohort study at a single tertiary care referral center. METHODS: The study recruited 19 patients with retinopathy, harboring likely disease-causing variants in IQCB1. Demographic data and clinical presentation, best corrected visual acuity (BCVA), fundus appearance, optical coherence tomography (OCT) and autofluorescence features, electroretinography (ERG) and molecular genetics are reported. RESULTS: Ten patients had best corrected visual acuity better than 1.0 LogMAR, and BCVA remained stable till the last review. Seven patients had a vision of hand movements or worse in at least one eye at presentation. There was no correlation found between age of onset and severity of vision loss. Nine patients (47.4%) had a diagnosis of end-stage renal failure at presentation. The other 10 patients (52.6%) had a diagnosis of non-syndromic IQCB1-retinopathy and maintained normal renal function until the last follow-up. The mean age at diagnosis of renal failure was 26.3 ±19.8 years. OCT showed ellipsoid zone (EZ) disruption with foveal sparing in 8/13 patients. All patients had stable OCT findings. Full-field ERGs in four adults revealed a severe cone-rod dystrophy and three children had extinguished ERGs. We identified 17 IQCB1 variants, all predicted to cause loss of function. CONCLUSION: IQCB1-retinopathy is a severe early-onset cone-rod dystrophy. The dissociation between severely decreased retinal function and relative preservation of retinal structure over a wide age window makes the disease a candidate for gene therapy.


Asunto(s)
Electrorretinografía , Angiografía con Fluoresceína , Tomografía de Coherencia Óptica , Agudeza Visual , Humanos , Masculino , Femenino , Tomografía de Coherencia Óptica/métodos , Estudios Retrospectivos , Agudeza Visual/fisiología , Adulto , Adolescente , Niño , Adulto Joven , Persona de Mediana Edad , Angiografía con Fluoresceína/métodos , Preescolar , Mutación , Enfermedades de la Retina/genética , Enfermedades de la Retina/diagnóstico , Enfermedades de la Retina/fisiopatología , Análisis Mutacional de ADN , Proteínas de Unión a Calmodulina
3.
J Viral Hepat ; 21(2): 78-89, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24383921

RESUMEN

In 1978, the first case of hepatitis E was identified as non-A, non-B hepatitis. Hepatitis E virus (HEV) infection is believed to be one of the common causes of enterically transmitted acute hepatitis in developing countries and is rare in developed countries, except in patients with a history of travel. However, an increasing number of chronic HEV infection cases have recently been reported in developed countries. In these countries, immunosuppressed patients with HEV infection, such as organ transplant recipients, human immunodeficiency virus (HIV)-infected patients or patients with haematological malignancies, could develop chronic hepatitis E (CHE) infection. Approximately 60% of HEV infections in immunocompromised patients after solid organ transplantation evolve to CHE without antiviral treatment. Clinical manifestations of CHE are often nonspecific symptoms. Many patients with CHE infection are asymptomatic, but some have jaundice, fatigue, abdominal pain, fever and asthenia. Several extrahepatic manifestations have also been reported. Although chronic HEV infection can result in progressive severe liver failure and cirrhosis, diagnosis is often controversial because of the lack of specific diagnostic criteria. Many CHE cases are diagnosed by HEV RNA-positive serum or stool for >6 months. Immunosuppressive drugs, interferon-alpha and ribavirin have been used for treatment. Diagnostic reverse-transcription polymerase chain reaction is useful for estimating treatment efficacy. Preventive measures for HEV infection have been discussed, while systematic guidelines have not yet been reported.


Asunto(s)
Hepatitis E/epidemiología , Hepatitis E/patología , Hepatitis Crónica/epidemiología , Hepatitis Crónica/patología , Salud Global , Hepatitis E/diagnóstico , Hepatitis E/prevención & control , Hepatitis Crónica/diagnóstico , Hepatitis Crónica/prevención & control , Humanos , Huésped Inmunocomprometido
4.
Anticancer Res ; 21(4A): 2265-72, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11724281

RESUMEN

The in vivo gene delivery of E. coli cytosine deaminase (cd) cDNA and systemic 5-fluorocytosine (5-FC) administration have been studied extensively because of their clinical relevance to cancer gene therapy. This approach has the potent advantage of a stronger bystander effect compared to the previous thymidine kinase suicide gene system of the herpes simplex virus. However, 5-fluorouracil (5-FU), an active metabolite in cd with 5-FC therapy, is not always effective for every type of tumor since the enzymes responsible for further drug metabolism vary significantly in each tissue. In this study, we aimed to increase the sensitivity of 5-FU by transduction of thymidine phosphorylase (dThdPase) cDNA into brain tumor cells. After retroviral transfer of the cDNA, we obtained 9L murine gliosarcoma cells showing stable expression of the target enzyme (9L-dThdPase). The growth of the cells was identical to wild type (9L-WT) or control-vector transfected (9L-Neo) cells in vitro. Sensitivity to 5-FU was increased in 9L-dThdPase cells. After the adenoviral delivery of cytosine deaminase gene into these cells, 9L-dThdPase cells also demonstrated an increased sensitivity to 5-FC. Moreover, we showed that transduction of dThdPase cDNA prolongs the survival of animals bearing intracerebral tumors after experimental in vivo cytosine deaminase gene therapy. These results suggest that transduction of thymidine phosphorylase may be a beneficial approach to increasing the efficacy of cd/5-FC suicide gene therapy in certain types of tumor.


Asunto(s)
Antimetabolitos Antineoplásicos/farmacología , Neoplasias Encefálicas/terapia , ADN Complementario/genética , Flucitosina/farmacología , Terapia Genética/métodos , Gliosarcoma/terapia , Nucleósido Desaminasas/genética , Timidina Fosforilasa/genética , Adenoviridae/genética , Animales , Antimetabolitos Antineoplásicos/farmacocinética , Neoplasias Encefálicas/enzimología , Neoplasias Encefálicas/genética , Citosina Desaminasa , ADN Complementario/administración & dosificación , Flucitosina/farmacocinética , Fluorouracilo/farmacocinética , Fluorouracilo/farmacología , Vectores Genéticos/genética , Gliosarcoma/enzimología , Gliosarcoma/genética , Masculino , Nucleósido Desaminasas/metabolismo , Ratas , Ratas Endogámicas F344 , Timidina Quinasa/genética , Timidina Quinasa/metabolismo , Timidina Fosforilasa/biosíntesis , Timidina Fosforilasa/metabolismo , Transducción Genética
5.
Masui ; 50(1): 76-9, 2001 Jan.
Artículo en Japonés | MEDLINE | ID: mdl-11211759

RESUMEN

We evaluated the effectiveness of transtracheal heating and humidification system in maintaining body temperature during general anesthesia with low flow gases in 12 gastric cancer patients. Patients were divided into two group; Control group A in which a hot-water circulating system was used and group B in which a transtracheal heating and humidification system by ANAMED HUMITUBE was used, during gastric cancer operation. Compared to the hot-water circulating system, the transtracheal heating and humidification system is more effective for maintaining body temperature and humidification after abdominal lavage by warm saline water. But there was no difference between the two groups about awakening from general anesthesia. We concluded that transtracheal heating and humidification system by ANAMED HUMITUBE is effective in maintaining body temperature under general anesthesia with low flow gases.


Asunto(s)
Anestesia General/instrumentación , Temperatura Corporal , Hipertermia Inducida/instrumentación , Tráquea , Anciano , Humanos , Persona de Mediana Edad , Monitoreo Intraoperatorio , Neoplasias Gástricas/cirugía , Tráquea/fisiología
6.
Plant Cell Physiol ; 41(1): 110-3, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10750715

RESUMEN

A stress-induced substance(s) (factor C) incubated with norepinephrine (NE) has strong flower-inducing activity in Lemna paucicostata. We isolated an essential component (FIF) of factor C, and clarified its chemical structure as 9-hydroxy-10-oxo-12(Z),15(Z)-octadecadienoic acid, an alpha-ketol derivative of linolenic acid, which is formed via 9-hydroperoxy linolenic acid. Synthesized FIF showed flower-inducing activity after incubation with NE (factor C activity) equivalent to that formed in the stressed Lemna. Jasmonic acid and 13-hydroxy-12-oxo-9(Z),15(Z)-octadecadienoic acid (12,13-alpha-ketol linolenic acid), both of which are formed via 13-hydroperoxide of linolenic acid and all other derivatives of FIF synthesized by chemical and enzymatic processes failed to show the factor C activity. These results suggest that the molecular structure of FIF is very specific for the factor C activity.


Asunto(s)
Ácidos Grasos Insaturados/metabolismo , Magnoliopsida/crecimiento & desarrollo , Estructuras de las Plantas/crecimiento & desarrollo , Ácido alfa-Linolénico/análogos & derivados , Ácido alfa-Linolénico/metabolismo , Ácidos Grasos Insaturados/química , Ácidos Grasos Insaturados/farmacología , Calor , Magnoliopsida/efectos de los fármacos , Norepinefrina/química , Norepinefrina/farmacología , Presión Osmótica , Estructuras de las Plantas/efectos de los fármacos , Relación Estructura-Actividad , Agua/fisiología , Ácido alfa-Linolénico/química , Ácido alfa-Linolénico/farmacología
7.
J Neurol Sci ; 173(2): 109-12, 2000 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-10675653

RESUMEN

Cranial magnetic resonance images (MRI) of the cerebral areas of 40 patients with multiple system atrophy (MSA) and of 61 age-matched controls were analyzed. The cerebral area of MSA patients was 131. 95+/-15.89 cm(2) (mean+/-S.D.), which was significantly smaller than that of normal controls at 149.01+/-10.93 cm(2) (P<0.0001). All 23 MSA cases subjected to the MRI study over a 1-year period showed progressive cerebral atrophy, and the atrophy rate was 2.46+/-1. 66%/year. There were no significant differences within the MSA subtypes or between gender. The progression of cerebral atrophy in MSA correlated more with duration (r=-0.634) than age (r=-0.421). We conclude that MRI findings throughout the course of MSA suggest progressive cerebral atrophy, which is common in all subtypes and reflects duration of the disease rather than age.


Asunto(s)
Encéfalo/patología , Imagen por Resonancia Magnética , Atrofia de Múltiples Sistemas/patología , Anciano , Atrofia , Trastornos del Conocimiento/etiología , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Atrofia de Múltiples Sistemas/diagnóstico , Atrofia de Múltiples Sistemas/psicología
8.
Int J Cancer ; 83(5): 620-4, 1999 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-10521797

RESUMEN

Our purpose was to determine the environmental risks in the development of esophageal cancer in Ci-Xian, which has one of the highest incidences of esophageal cancer in China. The subjects included 404, 352 and 400 inhabitants living in high-, medium-, and low-incidence areas of esophageal cancer, as well as 301 esophageal cancer patients. A food intake-frequency survey using a 7-day weighted inventory questionnaire was conducted on these individuals. Questions on occupation, working conditions, income per year, family disease history, medical complaints, and demographic features were also included in the questionnaire. The levels of nitrogen compounds in selected samples of well water were also measured in each of the 3 areas. Clear-cut differences in food intake were seen among inhabitants living in the 3 different areas, suggesting that regional differences in nutritional styles do exist. In both males and females, the intake of potatoes, fruit, vegetables, and meat were significantly lower in inhabitants living in the high-incidence area than in the other inhabitants, much the same as that of cancer patients. A low intake of carotene, and vitamins A and C was also seen in populations living in the high-incidence area of esophageal cancer. The well water polluted with nitrogen compounds was significantly related to the high incidence of esophageal cancer. In contrast, tobacco, alcohol consumption, and the intake of pickled vegetables and moldy foods did not relate to the different incidence rates. Our results suggest that low intake of fruit, vegetables, potatoes and meat, and the quality of well water may be important factors in the development of esophageal cancer in Ci-Xian.


Asunto(s)
Neoplasias Esofágicas/etiología , Estado Nutricional , Abastecimiento de Agua , Adulto , Factores de Edad , Consumo de Bebidas Alcohólicas/epidemiología , China/epidemiología , Neoplasias Esofágicas/epidemiología , Conducta Alimentaria , Femenino , Humanos , Incidencia , Masculino , Encuestas Nutricionales , Factores de Riesgo , Factores Sexuales , Fumar/epidemiología , Factores Socioeconómicos , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua/análisis
9.
J Pept Sci ; 5(7): 313-22, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10442767

RESUMEN

The design and synthesis of cyclic mimetics of VCAM-1 protein that reproduce the integrin-binding domain are presented. The unprotected peptide precursor 37-43, Thr-Gln-Ile-Asp-Ser-Pro-Leu, was grafted onto functional templates of type naphthalene, biphenyl and benzyl through the chemoselective formation of C- and N-terminal oximes resulting in a mixture of four isomeric forms due to syn-anti isomerism of the oxime bonds. Some isomers could be monitored by HPLC and identified by NMR. The molecule containing a naphthalene-derived template was found to inhibit the VCAM-1/VLA-4 interaction more efficiently than previously reported for sulfur-bridged cyclic peptides containing similar sequences. The finding confirms the importance of incorporating conformational constraints between the terminal ends of the peptide loop 37-43 in the design of synthetic inhibitors of the VCAM-1/integrin interaction.


Asunto(s)
Imitación Molecular , Molécula 1 de Adhesión Celular Vascular/química , Secuencia de Aminoácidos , Animales , Línea Celular , Cromatografía Líquida de Alta Presión , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Ratones , Oligopéptidos/química , Oligopéptidos/metabolismo , Unión Proteica , Conformación Proteica , Molécula 1 de Adhesión Celular Vascular/metabolismo
10.
Nihon Koshu Eisei Zasshi ; 46(2): 103-12, 1999 Feb.
Artículo en Japonés | MEDLINE | ID: mdl-10331295

RESUMEN

The purpose of this study is to develop a Japanese version of a self efficacy scale for health promotion activities by the elderly. In September to October 1997, we asked all of 1758 persons aged 65 and over who were living in a village in Nagano Prefecture to answer a questionnaire. The questionnaire included 15 self efficacy items for health promotion, Activities of Daily Living (ADL), general self efficacy, health behavior, and community activities. The present study examined reliability and validity of the scale by investigating the correlation to other factors. 1173 of the subjects completed the answer sheet by themselves. The mean age of the subjects was 72.9 +/- 6.1, and 54.7% were female, the education level of 52.2% was middle school, 54.0% worked as a laborers, and 41 persons (3.5%) needed help in instrumental ADL. Almost half of the subjects participated in various community activities. When applied to the 1173 subjects, the first principal component accounted for 53.9% of variance. We considered a self efficacy scale for health promotion by using the sum of 15 items. Alpha coefficient of the scale was 0.93 and test-retest reliability was 0.68, showing the reliability of the scale. Criterion-related validity was demonstrated by the significant relationship between the self efficacy scale and general self efficacy (r = 0.42). The score of the 15-item version did not correlate with age and sex but ADL and health behavior (r = 0.29, 0.21, p < 0.001). High self efficacy was found among those who had high self rated health, and participated in health counseling, health screening, golden-age community center activity, and volunteer activities. This scale can be used to measure personal belief for health promotion as well as the effects of interventions to alter health behaviors. To standardize the scale, further study of urban dwelling elderly and the disabled elderly is necessary.


Asunto(s)
Anciano/psicología , Promoción de la Salud , Autoeficacia , Actividades Cotidianas , Anciano de 80 o más Años , Femenino , Humanos , Japón , Masculino , Encuestas y Cuestionarios
12.
Cancer Biochem Biophys ; 15(4): 257-61, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9224561

RESUMEN

The effect of high pressure on the viability of Ehrlich ascites tumor cells was examined. The tumor cells were subjected to various pressures (0.1-150 MPa) for 30 min at 37 degrees C. The viability of pressure-treated cells was examined by the dye exclusion method. The number of stained cells increased significantly at pressures above 130 MPa. In addition, the pressure-treated cells were intraperitoneally inoculated into the mice. The tumor cells which were subjected to pressures below 110 MPa proliferated in the peritoneal cavity of the mice, so that the mice died. In contrast, the mice, which were inoculated with the tumor cells treated at pressures above 130 MPa, remained alive. These results suggest that the destruction of the tumor cells begins to occur at about 130 MPa.


Asunto(s)
Carcinoma de Ehrlich/patología , Presión Hidrostática , Animales , Carcinoma de Ehrlich/metabolismo , División Celular/fisiología , Ratones , Ratones Endogámicos , Azul de Tripano/farmacocinética
13.
J Dermatol Sci ; 14(3): 199-206, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9138477

RESUMEN

We examined how and to what extent the constitution of melanin and the expression, as well as the activity, of melanosomal proteins influence the production of melanin pigment by human black and light brown melanocytes, Mel (b) cells and Mel (l) cells, respectively. Melanin pigment in Mel (b) and Mel (l) cells consisted of a mixture of eumelanin and pheomelanin, and Mel (b) cells contained a larger amount. The signal intensity ratio of eumelanin to pheomelanin was similar in both cell types, though the two cell types differed in appearance. Tyrosinase activity and the amount of tyrosinase-related protein (TRP-1) of Mel (b) cells were higher than those of Mel (l) cells. Dopachrome tautomerase (DCT) activity and the amount of 6H5MICA were reduced in Mel (b) cells in comparison with Mel (l) cells. No significant difference in DHICA-converting activity or catechol-O-methyltransferase activity was found between Mel (b) and Mel (l) cells. There was no correlation between DHICA-converting activity and amount of TRP-1. These results suggest that the difference in the pigmentation of the two human melanocyte cell lines, Mel (b) and Mel (l), is derived from differences in the activity and expression of tyrosinase, TRP-1 and DCT, which affect the content and constitution of melanin polymers.


Asunto(s)
Pueblo Asiatico/genética , Población Negra/genética , Oxidorreductasas Intramoleculares , Melaninas/metabolismo , Melanocitos/metabolismo , Glicoproteínas de Membrana , Pigmentación de la Piel/genética , Población Blanca/genética , Northern Blotting , Catecol O-Metiltransferasa/análisis , Catecol O-Metiltransferasa/genética , Catecol O-Metiltransferasa/metabolismo , Células Cultivadas , Cromatografía Líquida de Alta Presión , Espectroscopía de Resonancia por Spin del Electrón , Citometría de Flujo , Regulación de la Expresión Génica , Humanos , Recién Nacido , Isomerasas/análisis , Isomerasas/genética , Isomerasas/metabolismo , Masculino , Melaninas/análisis , Melaninas/genética , Melanocitos/química , Melanocitos/citología , Monofenol Monooxigenasa/análisis , Monofenol Monooxigenasa/genética , Monofenol Monooxigenasa/metabolismo , Oxidorreductasas/análisis , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Proteínas/análisis , Proteínas/genética , Proteínas/metabolismo , ARN Mensajero/análisis , ARN Mensajero/genética , ARN Mensajero/metabolismo , Pigmentación de la Piel/fisiología
14.
Eur J Biochem ; 241(1): 77-82, 1996 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-8898891

RESUMEN

A secretory proteinase inhibitor was isolated from the latex of green fruits of papaya (Carica papaya). The protein exhibited stoichiometric inhibition of bovine trypsin and alpha-chymotrypsin by the same site or overlapping binding sites. The complete covalent structure consisting of 184 amino acids and two disulfide bonds was determined by protein analysis. During the structural analysis, a procedure was established to separate very hydrophilic peptides by reverse-phase HPLC. The result revealed that the latex protein belongs to an extensively diverse plant protein family that includes inhibitors of serine, cysteine and aspartic proteases, a taste-modifying protein, wound responsive proteins, storage proteins, amylase inhibitors and even an oxidoreductase. In this superfamily, the latex proteinase inhibitor is most similar to the curious protein, miraculin, which makes sour food taste sweet. Two carbohydrate chains, each probably composed of (mannose)5, (xylose)1, (fucose)0-2, and (N-acetylglucosamine)2 residues, were attached to asparagine 84 and 90. Mass-spectrometric and compositional analysis suggested that they may represent a new class of plant xylose-containing carbohydrate chains with five mannose residues.


Asunto(s)
Glicoproteínas/metabolismo , Inhibidores de Proteasas/química , Secuencia de Aminoácidos , Secuencia de Bases , Cromatografía en Gel , Cromatografía Líquida de Alta Presión , Quimotripsina/metabolismo , Bromuro de Cianógeno/metabolismo , Disulfuros/química , Frutas/química , Glicoproteínas/química , Espectrometría de Masas , Datos de Secuencia Molecular , Peso Molecular , Monosacáridos/análisis , Fragmentos de Péptidos/química , Polisacáridos/química , Inhibidores de Proteasas/aislamiento & purificación , Análisis de Secuencia , Homología de Secuencia de Aminoácido , Especificidad por Sustrato , Tripsina/metabolismo
15.
Chem Pharm Bull (Tokyo) ; 44(9): 1680-92, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8855362

RESUMEN

Five new resin-glycosides, named merremosides a (1), b (2), c (3), d (4), and e (5), were isolated from the tuber of Merremia mammosa (LOUR.) HALLIER f. (Convolvulaceae), an Indonesian medicinal plant. The structures of 1, 2, 3, 4, and 5 have been elucidated on the basis of chemical and physiochemical evidence, including syntheses of (11S)-(+)- and (11R)-(--)-jalapinolic acid (16b and 18b) and the glycosidic acid designated as merremoside i (6).


Asunto(s)
Glicósidos/química , Oligosacáridos/química , Plantas Medicinales/química , Secuencia de Carbohidratos , Glicósidos/aislamiento & purificación , Datos de Secuencia Molecular , Estructura Molecular , Oligosacáridos/aislamiento & purificación , Resinas de Plantas/química
16.
Chem Pharm Bull (Tokyo) ; 44(9): 1693-9, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8855363

RESUMEN

Four new resin-glycosides named merremosides f (6), g (7), h1 (8), and h2 (9) were isolated from the tuber of Merremia mammosa (Lour.) Hallier f. (Convolvulaceae), an Indonesian medicinal plant. Their chemical structures have been elucidated on the bases of their chemical and physicochemical properties.


Asunto(s)
Glicósidos/química , Oligosacáridos/química , Plantas Medicinales/química , Secuencia de Carbohidratos , Glicósidos/aislamiento & purificación , Datos de Secuencia Molecular , Estructura Molecular , Oligosacáridos/aislamiento & purificación , Resinas de Plantas/química
17.
Chem Pharm Bull (Tokyo) ; 43(10): 1647-53, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8536338

RESUMEN

Nine myriocin analogs, 2-epi-myriocin, 14-deoxomyriocin, Z-14-deoxomyriocin, and nor-deoxomyriocins, were synthesized from 2-deoxy-D-glucose via common intermediates used in previous myriocin and Z-myriocin syntheses. Immunosuppressive activities of those myriocin analogs on mouse allogeneic mixed lymphocyte reaction were examined, and Z-14-deoxomyriocin was found to show the most potent activity among them. The structure-activity relationships are discussed.


Asunto(s)
Inmunosupresores/síntesis química , Animales , Ácidos Grasos Monoinsaturados/síntesis química , Ácidos Grasos Monoinsaturados/farmacología , Inmunosupresores/química , Inmunosupresores/farmacología , Prueba de Cultivo Mixto de Linfocitos , Espectroscopía de Resonancia Magnética , Ratones , Fotoquímica , Espectrometría de Masa Bombardeada por Átomos Veloces , Relación Estructura-Actividad
18.
J Nat Prod ; 58(5): 739-43, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7623048

RESUMEN

Bioassay-guided fractionation monitored by mushroom tyrosinase (EC 1.14.18.1) activity, afforded six inhibitors from three Bolivian medicinal plants, Buddleia coriacea, Gnaphalium cheiranthifolium, and Scheelea princeps. These inhibitors, which are all known phenolic compounds, inhibited the oxidation of L-3,4-dihydroxyphenylalanine (L-DOPA) mediated by a mushroom tyrosinase.


Asunto(s)
Monofenol Monooxigenasa/antagonistas & inhibidores , Plantas Medicinales/química , Basidiomycota/enzimología , Bolivia
19.
Chem Pharm Bull (Tokyo) ; 42(12): 2662-4, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7697780

RESUMEN

Eight new myriocin analogs, 2-epi-myriocin, Z-14-deoxomyriocin, and nor-deoxomyriocins, and a known myriocin derivative, 14-deoxomyriocin, were synthesized from 2-deoxy-D-glucose via common intermediates in previous myriocin and Z-myriocin syntheses. The immunosuppressive activities of new myriocin analogs and Z-myriocin on mouse allogeneic mixed lymphocyte reaction were examined, and, by comparing with those of myriocin and 14-deoxomyriocin, some structure-activity relationships have been found.


Asunto(s)
Inmunosupresores/síntesis química , Animales , Desoxiglucosa/química , Ácidos Grasos Monoinsaturados/síntesis química , Ácidos Grasos Monoinsaturados/farmacología , Inmunosupresores/farmacología , Prueba de Cultivo Mixto de Linfocitos , Ratones , Relación Estructura-Actividad
20.
J Nat Prod ; 57(4): 545-51, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8021657

RESUMEN

Anacardic acids, 2-methylcardols, and cardols isolated from various parts of the cashew [Anacardium occidentale] (Anacardiaceae) fruit have been found to exhibit tyrosinase inhibitory activity. Kinetic studies with the two principal active compounds, 6-[8(Z),11(Z),14-pentadecatrienyl]salicylic acid and 5-[8(Z),11(Z),14-pentadecatrienyl]resorcinol, have indicated that both of these phenolic compounds exhibit characteristic competitive inhibition of the oxidation of L-3,4-dihydroxyphenylalanine (L-DOPA) by mushroom tyrosinase.


Asunto(s)
Ácidos Anacárdicos , Monofenol Monooxigenasa/antagonistas & inhibidores , Nueces/química , Resorcinoles/aislamiento & purificación , Salicilatos/aislamiento & purificación , Basidiomycota/enzimología , Cinética , Levodopa/metabolismo , Monofenol Monooxigenasa/metabolismo , Oxidación-Reducción , Resorcinoles/farmacología , Salicilatos/farmacología , Relación Estructura-Actividad
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