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1.
Arch Womens Ment Health ; 24(3): 455-461, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33009578

RESUMEN

To evaluate changes in concentrations of selected biomarkers, neurotrophic factors, and growth factors in the cerebrospinal fluid during pregnancy. A prospective observational study was conducted in 32 pregnant women undergoing gynecological and obstetrical surgery under spinal anesthesia in a university hospital. Beta-amyloid(1-42) and beta-amyloid(1-40) peptides, brain-derived neurotrophic factor, glial cell line-derived neurotrophic factor, and vascular endothelial growth factor were analyzed in cerebrospinal fluid using an enzyme-linked immunosorbent assay. Eight women in second trimester pregnancy who underwent spinal anesthesia for gynecological or obstetrical surgery were compared with 24 matched women in third trimester pregnancies. CSF concentrations of beta-amyloid(1-42) were significantly higher in third trimester pregnancies (p = 0.025). During third trimester, the beta-amyloid ratio correlated with the vascular endothelial growth factor (rs = 0.657; p = 0.008). Higher concentrations of beta-amyloid(1-42) in cerebrospinal fluid of third trimester pregnancies and correlations between the beta-amyloid ratio and the vascular endothelial growth factor support the hypothesis that beta-amyloid peptides are involved in complex adaptive brain alterations during pregnancy.


Asunto(s)
Péptidos beta-Amiloides/líquido cefalorraquídeo , Fragmentos de Péptidos/líquido cefalorraquídeo , Embarazo/líquido cefalorraquídeo , Biomarcadores , Factor Neurotrófico Derivado del Encéfalo/líquido cefalorraquídeo , Femenino , Factor Neurotrófico Derivado de la Línea Celular Glial/líquido cefalorraquídeo , Humanos , Segundo Trimestre del Embarazo , Estudios Prospectivos , Factor A de Crecimiento Endotelial Vascular/líquido cefalorraquídeo
2.
Toxicol Sci ; 61(1): 128-34, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11294983

RESUMEN

Sperm analyses are often incorporated into reproductive toxicity studies in rats. Due to the relative ease of collecting multiple samples throughout a study, semen analysis in non-rodents such as dogs offers the opportunity to assess potential development of functional effects of compounds on male reproduction over time. In the present study, semen parameters were evaluated in beagle dogs during and at termination of a chronic toxicity study with the 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor, atorvastatin. Male dogs received 0, 10, 40, or 120 mg/kg orally in gelatin capsules for up to 104 weeks (n = 10/group). After 52 weeks of dosing, 3 dogs/group were euthanized, and 2/group were withdrawn from treatment for a 12-week reversal period and euthanized at Week 64. The remaining 5/group continued treatment until Week 104. Semen was collected from all animals for 3 consecutive weeks prior to termination of the 52-week animals (Weeks 50, 51, 52) for analysis of sperm parameters, using manual methods of evaluation. Semen was collected from the remaining animals at Weeks 64, 78, 91, and 104, and was analyzed. At necropsy, testes, epididymides, and prostates were weighed and evaluated histologically, and epididymal sperm counts were determined. Serum cholesterol was decreased 25--60% at all doses during the study. There were no drug-related differences in semen volume and color, total sperm count, and sperm concentration, morphology, progressiveness, and percent motility during treatment with atorvastatin. There were also no effects on reproductive organ weights or histopathology, and no effects on epididymal sperm count. Thus, incorporation of semen analyses into this study allowed the evaluation of potential male reproductive effects in dogs at multiple time points during the study. Statistical power calculations demonstrated acceptable statistical power (> 80%) for semen sperm count, concentration, morphology, and motility with group sizes of 8--10 animals, and for semen sperm count and concentration or epididymal sperm count with group sizes of 3--5 animals, using the methodology described in this paper.


Asunto(s)
Acilcoenzima A/antagonistas & inhibidores , Acilcoenzima A/efectos de los fármacos , Colesterol/análisis , Epidídimo/efectos de los fármacos , Ácidos Heptanoicos/análisis , Ácidos Heptanoicos/farmacología , Tamaño de los Órganos/efectos de los fármacos , Próstata/efectos de los fármacos , Pirroles/análisis , Pirroles/farmacología , Semen/citología , Semen/efectos de los fármacos , Motilidad Espermática/efectos de los fármacos , Espermatozoides/anomalías , Espermatozoides/citología , Espermatozoides/efectos de los fármacos , Testículo/efectos de los fármacos , Animales , Atorvastatina , Colesterol/sangre , Perros , Eyaculación , Epidídimo/crecimiento & desarrollo , Epidídimo/patología , Ácidos Heptanoicos/sangre , Masculino , Próstata/crecimiento & desarrollo , Próstata/patología , Pirroles/sangre , Recuento de Espermatozoides , Testículo/crecimiento & desarrollo , Testículo/patología , Factores de Tiempo
3.
Org Lett ; 2(19): 2921-2, 2000 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-10986072

RESUMEN

A short formal synthesis of squalamine is described, utilizing the biotransformation product 2, which is available in one step from commercially available 3-keto-23,24-bisnorchol-4-en-22-ol (1). Regioselective C-22 oxidation and C-24 sulfation of the corresponding alcohols in the presence of a free C-7 alcohol make for an efficient preparation of squalamine intermediate 11.


Asunto(s)
Inhibidores de la Angiogénesis/síntesis química , Colestanoles/síntesis química , Hidroxilación , Hongos Mitospóricos/metabolismo , Noresteroides/química , Noresteroides/metabolismo
4.
Lipids ; 32(1): 79-84, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9075197

RESUMEN

Streptomyces catenulae catalyzed the oxidation of alpha-tocopherol to alpha-tocopherolquinone. Nitrotocopherols isolated from S. catenulae grown in defined culture medium containing delta- and gamma-tocopherols are formed by a combination of enzymatic nitrate reduction to nitrite, and subsequent nonenzymatic acid-catalyzed nitration. The incorporation of 15N18O3-into nitrated tocopherols confirmed the origin of the nitrating species. Structures of chromatographically purified products obtained from S. catenulae transformations of tocopherols were deduced by spectral (mass spectrometry, 1H-, and 13C-nuclear magnetic resonance) analyses.


Asunto(s)
Streptomyces/metabolismo , Vitamina E/metabolismo , Biotransformación , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Estructura Molecular , Nitratos/metabolismo , Nitritos/metabolismo , Nitrocompuestos/metabolismo , Vitamina E/aislamiento & purificación
5.
Fundam Appl Toxicol ; 32(2): 285-92, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8921332

RESUMEN

Fertility and reproduction studies were conducted in rats with the 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor, atorvastatin. Male rats received vehicle (0.5% methylcellulose) or atorvastatin at 20, 100, or 175 mg/kg by oral gavage for 11 weeks prior to mating with untreated females; treatment continued throughout mating and until necropsy on Day 115. An untreated control group of males was also included in the same procedures. Dose-related body weight gain suppressions of 17 and 25%, and food consumption suppressions of 7 and 16%, occurred during the 11-week premating treatment period at 100 and 175 mg/kg, respectively, compared with vehicle controls. There were no treatment-related effects on testes, epididymides, or accessory organs weights, testicular or epididymal sperm counts, sperm motility, or sperm morphology during Week 15 of treatment. Plasma drug concentrations during Week 15 increased with dose to a Cmax of 1820 +/- 1020 ng eq/ml at 175 mg/kg. There were no effects on copulation or fertility indices, number of days to mating, or female reproductive parameters (number of implants, live fetuses, or pre- and postimplantation loss). In the female fertility study, female rats received vehicle (0.5% methylcellulose) or atorvastatin at 20, 100, or 225 mg/kg by oral gavage for 2 weeks prior to mating with untreated males; treatment continued throughout mating and until Gestation Day 7. Sperm-positive females were sacrificed on presumed Gestation Day 13 to 15 for evaluation of reproductive parameters. Body weight gain in atorvastatin groups was comparable to controls during the premating period, but was suppressed by 35% at 225 mg/kg during the treatment period of gestation (Days 0-8), and was significantly increased at 225 mg/ kg during the posttreatment period of gestation (Days 8-13). Plasma drug concentrations on premating treatment Day 14 increased with dose to a Cmax of 7030 +/- 3680 ng eq/ml at 225 mg/ kg. The mean number of estrous cycles, copulation and fertility indices, number of days to mating, and number of viable litters were comparable between groups. In addition, term sacrifice parameters (number of corpora lutea, implants, live fetuses, pre- and postimplantation loss) were not significantly different between groups. Thus, these studies demonstrate no adverse effects of atorvastatin on fertility and reproduction in rats at doses up to 175 and 225 mg/kg in males and females, respectively, and 20 mg/kg was a no-effect dose.


Asunto(s)
Anticolesterolemiantes/farmacología , Inhibidores Enzimáticos/farmacología , Fertilidad/efectos de los fármacos , Ácidos Heptanoicos/farmacología , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Pirroles/farmacología , Reproducción/efectos de los fármacos , Animales , Anticolesterolemiantes/farmacocinética , Atorvastatina , Inhibidores Enzimáticos/farmacocinética , Femenino , Ácidos Heptanoicos/farmacocinética , Masculino , Pirroles/farmacocinética , Ratas , Ratas Sprague-Dawley
6.
Reprod Toxicol ; 10(3): 231-5, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8738561

RESUMEN

Motion parameters were compared in rat sperm isolated from the distal vas deferens and the cauda epididymidis. Motion parameters were also compared in 20 microns and 50 microns deep muCellTM chambers using vas deferens sperm. Video recorded samples were analyzed manually for motility, and analyzed by a computer automated sperm analysis (CASA) system for motility, curvilinear velocity, linearity, mean and maximum amplitude of lateral head displacement (ALH), and beat/cross frequency using two versions of CellSoftTM (Series 3,000 and Series 4,000). Motility, linearity, and beat/cross frequency were not significantly different between sperm from vas deferens and cauda epididymidis, while velocity and ALH values were slightly greater in sperm from vas deferens than from cauda epididymidis. Sperm motility and linearity were not significantly different when analyzed in 20 microns and 50 microns mu CellTM chambers. Velocity and ALH values were slightly greater in 20 microns than in 50 microns chambers, and beat/cross frequency was slightly lower in 20 microns than in 50 microns chambers. Sperm motility was significantly greater when determined manually than when determined with the Series 3,000 but manually determined sperm motility was only slightly greater than motility determined with the Series 4,000. Several sperm motion parameters differed significantly between the Series 3,000 and Series 4,000 (curvilinear velocity, mean and maximum ALH, linearity, and beat/cross frequency) but the relative variability of the systems was comparable. Compared with manual determinations, the Series 3,000 overestimated and the Series 4,000 underestimated the number of cells analyzed for motility. Therefore, differences existed between manual and CellSoft (Series 3,000 and 4,000) analysis of sperm motility and number of cells, and between CellSoft systems in the analysis of sperm motion parameters. However, only minimal differences in sperm motion parameters were observed between the vas deferens and cauda epididymidis, and between 20 microns and 50 microns deep muCell chambers.


Asunto(s)
Epidídimo/fisiología , Motilidad Espermática/fisiología , Conducto Deferente/fisiología , Análisis de Varianza , Animales , Recuento de Células , Diseño de Equipo , Procesamiento de Imagen Asistido por Computador , Masculino , Microscopía por Video , Ratas , Ratas Wistar , Espermatozoides/fisiología
7.
Reprod Toxicol ; 10(3): 237-44, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8738562

RESUMEN

Reproductive toxicity studies are increasingly including assessments of sperm parameters including motility, morphology, and counts. While these assessments can provide valuable information for the determination of potential reproductive toxicity, the methods for conducting the assessments have not been well developed in all laboratories and are continually evolving. The use of different methods in different laboratories makes comparison of data among laboratories difficult. To address the differences in methods, a working group was convened to discuss methods currently in use, share data, and try to reach consensus about optimal methods for assessing sperm parameters in rats, rabbits, and dogs. This article presents the consensus report, as well as future research needs, with the hope that optimized common methods will aid in the detection of reproductive effects and enhance interlaboratory comparisons.


Asunto(s)
Recolección de Datos/métodos , Recuento de Espermatozoides/métodos , Motilidad Espermática/fisiología , Espermatozoides/citología , Animales , Perros , Agencias Gubernamentales , Masculino , Conejos , Ratas , Sociedades Científicas , Especificidad de la Especie , Estados Unidos
8.
J Ind Microbiol ; 15(6): 457-71, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8821508

RESUMEN

In this review we examine the fascinating array of microbial and enzymatic transformations of ferulic acid. Ferulic acid is an extremely abundant, preformed phenolic aromatic chemical found widely in nature. Ferulic acid is viewed as a commodity scale, renewable chemical feedstock for biocatalytic conversion to other useful aromatic chemicals. Most attention is focused on bioconversions of ferulic acid itself. Topics covered include cinnamoyl side-chain cleavage; nonoxidative decarboxylation; mechanistic details of styrene formation; purification and characterization of ferulic acid decarboxylase; conversion of ferulic acid to vanillin; O-demethylation; and reduction reactions. Biotransformations of vinylguaiacol are discussed, and selected biotransformations of vanillic acid including oxidative and nonoxidative decarboxylation are surveyed. Finally, enzymatic oxidative dimerization and polymerization reactions are reviewed.


Asunto(s)
Ácidos Cumáricos/metabolismo , Secuencia de Aminoácidos , Biodegradación Ambiental , Datos de Secuencia Molecular
9.
Teratology ; 51(1): 11-9, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7597653

RESUMEN

The developmental toxicity of the anticonvulsant compound, ralitoline, was investigated in Sprague-Dawley rats administered oral doses of 0, 15, 60, 120, 180, or 240 mg/kg on days 6 through 15 of gestation. An untreated control group and a vehicle control group pair-fed to the high dose group were included. Maternal and fetal parameters were evaluated on day 21 of gestation. Fetuses were examined for external, visceral, and skeletal malformations and variations. Maternal death occurred at 180 and 240 mg/kg. Dose-dependent decreases in body weight, food consumption, and water consumption were observed at 60 mg/kg and above. Body weight gain during treatment was similar in the pair-fed and 240 mg/kg groups. Dose-related CNS signs (hypoactivity, ataxia, prostration, and/or convulsions) were observed at 60 mg/kg and above. Decreased numbers of live fetuses and increased postimplantation loss were observed in a dose-related manner at 120, 180, and 240 mg/kg while no changes occurred in pair-fed controls. Fetal body weights and placental weights were decreased in pair-fed controls and in the 120, 180, and 240 mg/kg groups. The percent fetuses per litter, and the percent litters with external/visceral malformations, were significantly increased at 120, 180, and 240 mg/kg compared with vehicle and pair-fed controls. Dose-related increases in cardiovascular malformations, specifically of the aortic arch (interrupted, stenotic, extra vessel), were apparent at 120 mg/kg and above. The incidence of skeletal variations was increased at 120 mg/kg and above.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Anomalías Inducidas por Medicamentos/etiología , Anticonvulsivantes/toxicidad , Aorta Torácica/anomalías , Tiazoles/toxicidad , Animales , Anorexia/inducido químicamente , Ataxia/inducido químicamente , Huesos/anomalías , Relación Dosis-Respuesta a Droga , Femenino , Retardo del Crecimiento Fetal/inducido químicamente , Reabsorción del Feto/inducido químicamente , Dosificación Letal Mediana , Embarazo , Complicaciones del Embarazo/inducido químicamente , Ratas , Ratas Sprague-Dawley , Convulsiones/inducido químicamente , Aumento de Peso/efectos de los fármacos
10.
Teratology ; 50(6): 387-94, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7778043

RESUMEN

The developmental toxicity of the 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor, atorvastatin, was investigated in pregnant rats and rabbits given daily oral doses during organogenesis. Rats received 0, 10, 100, or 300 mg/kg on days 6-15 of gestation, and rabbits received 0, 10, 50, or 100 mg/kg on days 6-18 of gestation. Maternal and fetal parameters were evaluated on day 20 (rats) or 29 (rabbits) of gestation. Live fetuses were examined for external, visceral, and skeletal malformations and variations. At 300 mg/kg in rats, 1 treatment-related death occurred on day 12 of gestation, and maternal body weight gain and food consumption were decreased during treatment (43% and 23%, respectively). In addition, 1 animal at 300 mg/kg had total litter resorption. Increased postimplantation loss (not statistically significant) and slightly decreased fetal body weight (statistically significant only in males) were also observed at 300 mg/kg. There were no significant differences between treated and control groups in the incidence of fetal malformations or variations. No maternal or developmental toxicity was observed in rats at 10 or 100 mg/kg. In rabbits, marked maternal toxicity (7 deaths, body weight loss during and after treatment, and decreased food consumption) and abortion occurred at 100 mg/kg. At 50 mg/kg, maternal toxicity (2 deaths and 72% body weight gain suppression) and abortion also occurred. There were no treatment-related effects on live litter size or sex ratio. At 50 and 100 mg/kg, nonstatistically significant increases in postimplantation loss and decreases in gravid uterine weight were observed, and at 100 mg/kg, decreases in fetal body weight were observed relative to controls.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Anticolesterolemiantes/toxicidad , Desarrollo Embrionario y Fetal/efectos de los fármacos , Ácidos Heptanoicos/toxicidad , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Pirroles/toxicidad , Pruebas de Toxicidad , Anomalías Inducidas por Medicamentos/etiología , Animales , Atorvastatina , Peso Corporal/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Femenino , Masculino , Embarazo , Conejos , Ratas , Ratas Sprague-Dawley
11.
Toxicol Lett ; 74(2): 99-119, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7940600

RESUMEN

In recent years, concern about possible female reproductive and developmental toxicity due to environmental contaminants, such as PCBs, has been growing. Because this area of toxicology had not been emphasized prior to this time, there are many gaps in current knowledge about female developmental and reproductive toxicology and only a limited number of validated tests to assay effects of toxicants on various parts of the reproductive and developmental cycle. This article reviews the current state of knowledge on this topic and also explores a variety of techniques for assessing female reproductive and developmental toxicity. These include an assay of the state of intercellular communication among the embryo, fetus and placenta; protocols for assessing toxicity in early pregnancy; and techniques for evaluating the role of glutathione in protecting the conceptus from xenobiotics.


Asunto(s)
Sustancias Peligrosas/efectos adversos , Exposición Materna/efectos adversos , Reproducción/efectos de los fármacos , Proyectos de Investigación , Desarrollo Embrionario y Fetal/efectos de los fármacos , Femenino , Uniones Comunicantes/efectos de los fármacos , Uniones Comunicantes/ultraestructura , Glutatión/fisiología , Humanos , Lactancia/efectos de los fármacos , Lactancia/fisiología , Masculino , Exposición Paterna , Placenta/efectos de los fármacos , Placenta/embriología , Embarazo , Reproducción/fisiología
12.
J Bacteriol ; 176(19): 5912-8, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7928951

RESUMEN

A ferulic acid decarboxylase enzyme which catalyzes the decarboxylation of ferulic acid to 4-hydroxy-3-methoxystyrene was purified from Pseudomonas fluorescens UI 670. The enzyme requires no cofactors and contains no prosthetic groups. Gel filtration estimated an apparent molecular mass of 40.4 (+/- 6%) kDa, whereas sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed a molecular mass of 20.4 kDa, indicating that ferulic acid decarboxylase is a homodimer in solution. The purified enzyme displayed an optimum temperature range of 27 to 30 degrees C, exhibited an optimum pH of 7.3 in potassium phosphate buffer, and had a Km of 7.9 mM for ferulic acid. This enzyme also decarboxylated 4-hydroxycinnamic acid but not 2- or 3-hydroxycinnamic acid, indicating that a hydroxy group para to the carboxylic acid-containing side chain is required for the enzymatic reaction. The enzyme was inactivated by Hg2+, Cu2+, p-chloromercuribenzoic acid, and N-ethylmaleimide, suggesting that sulfhydryl groups are necessary for enzyme activity. Diethyl pyrocarbonate, a histidine-specific inhibitor, did not affect enzyme activity.


Asunto(s)
Carboxiliasas/aislamiento & purificación , Ácidos Cumáricos/metabolismo , Guayacol/análogos & derivados , Pseudomonas fluorescens/enzimología , Secuencia de Aminoácidos , Tampones (Química) , Carboxiliasas/efectos de los fármacos , Carboxiliasas/metabolismo , Guayacol/metabolismo , Calor , Concentración de Iones de Hidrógeno , Metales/farmacología , Datos de Secuencia Molecular , Espectrofotometría , Especificidad por Sustrato
13.
J Biol Chem ; 268(32): 23954-8, 1993 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-8226936

RESUMEN

Resting cells of Rhodotorula rubra converted transferulic acid (1) to vanillic acid (2), then to guaiacol (3) and protocatechuic acid (4), under aerobic conditions. In an argon atmosphere, R. rubra transformed ferulic acid to vanillic acid and 4-hydroxy-3-methoxystyrene (5). Metabolites were isolated by solid-phase extraction and characterized by mass spectrometry, 1H, and 13C-nuclear magnetic resonance spectroscopy (NMR). The biotransformation of ferulic acid to vanillic acid by R. rubra cell-free extracts required CoA, ATP, and NAD+. Mass spectrometry and 13C-NMR were used to demonstrate the incorporation of oxygen from H2(18)O during the conversion of ferulic acid to vanillic acid. The results suggest a parallel between this bioconversion reaction and the beta-oxidation of fatty acids. Proton-carbon correlation NMR spectroscopy was used to demonstrate the specific incorporation of deuterium from D2O into guaiacol obtained from vanillic acid. The incorporation of deuterium implicates the involvement of a quinoid vanillic acid tautomer as an intermediate in the decarboxylation reaction.


Asunto(s)
Ácidos Cumáricos/metabolismo , Guayacol/metabolismo , Rhodotorula/metabolismo , Ácido Vanílico/metabolismo , Sistema Libre de Células , Cromatografía Líquida de Alta Presión , Cromatografía en Capa Delgada , Espectroscopía de Resonancia Magnética , Espectrometría de Masas
14.
J Nat Prod ; 56(11): 1993-4, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8289067

RESUMEN

The CHCl3 extract of Pseudomonas aeruginosa UI 29791 cultures afforded a novel fluorescent compound, aeruginol [1]. The structure of 1 was elucidated by spectroscopic methods, including uv, eims, cims, hreims, and 1H nmr. Aeruginol appears to be biosynthetically related to aeruginoic acid.


Asunto(s)
Fenoles/aislamiento & purificación , Pseudomonas aeruginosa/metabolismo , Tiazoles/aislamiento & purificación
15.
Appl Environ Microbiol ; 59(7): 2244-50, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8395165

RESUMEN

Saccharomyces cerevisiae (dry baker's yeast) and Pseudomonas fluorescens were used to convert trans-ferulic acid into 4-hydroxy-3-methoxystyrene in 96 and 89% yields, respectively. The metabolites were isolated by solid-phase extraction and analyzed by thin-layer chromatography and high-performance liquid chromatography. The identities of the metabolites were determined by 1H- and 13C-nuclear magnetic resonance spectroscopy and by mass spectrometry. The mechanism of the decarboxylation of ferulic acid was investigated by measuring the degree and position of deuterium incorporated into the styrene derivative from D2O by mass spectrometry and by both proton and deuterium nuclear magnetic resonance spectroscopies. Resting cells of baker's yeast reduced ferulic acid to 4-hydroxy-3-methoxyphenylpropionic acid in 54% yield when incubations were under an argon atmosphere.


Asunto(s)
Ácidos Cumáricos/metabolismo , Guayacol/análogos & derivados , Pseudomonas fluorescens/metabolismo , Saccharomyces cerevisiae/metabolismo , Biotransformación , Medios de Cultivo/química , Deuterio , Óxido de Deuterio , Guayacol/metabolismo , Agua
16.
Appl Environ Microbiol ; 59(3): 725-8, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8480999

RESUMEN

The fatty acid and positional specificities of Saccharomyces cerevisiae (UI-SACCH) and Schizosaccharomyces octosporus (NRRL Y-854) in the hydrolysis of lard were studied by using gas-liquid chromatography. Synthetic triglycerides were used to determine the positional specificities of the lipases of both organisms. Palmitic acid is specifically cleaved from all three triglyceride ester positions by S. cerevisiae, while S. octosporus was able to cleave stearic acid at either position 1 or position 3 of the glycerol moiety. Preparative scale fermentation with 200 g of lard per liter yielded 48.4 g of palmitic acid per liter with S. cerevisiae and 42 g of stearic acid per liter with S. octosporus. The free fatty acids produced by microbial transformation of lard were characterized spectrally (1H and C nuclear magnetic resonance and mass spectrometry) and chromatographically (thin-layer and gas chromatographies).


Asunto(s)
Grasas de la Dieta/metabolismo , Saccharomyces cerevisiae/metabolismo , Schizosaccharomyces/metabolismo , Cromatografía de Gases , Cromatografía en Capa Delgada , Ácidos Grasos/análisis , Fermentación/fisiología , Hidrólisis , Lipasa/metabolismo , Ácido Palmítico , Ácidos Palmíticos/metabolismo , Ácidos Esteáricos/metabolismo , Especificidad por Sustrato
17.
Appl Environ Microbiol ; 59(1): 281-4, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16348853

RESUMEN

We recently described a simple method for ascertaining the stereochemical purities of hydroxy fatty acids (S. H. El-Sharkawy, W. Yang, L. Dostal, and J. P. N. Rosazza, Appl. Environ. Microbiol. 58:2116-2122, 1992) based on the H-nuclear magnetic resonance spectral analysis of diastereomeric S-(+)-O-acetylmandelate esters of hydroxystearates. This report describes the stereochemistries of microbial hydrations of oleic acid to 10-hydroxystearic acid by Nocardia aurantia (also known as Rhodococcus rhodochrous) ATCC 12674, Nocardia restrictus ATCC 14887, Mycobacterium fortuitum UI-53387, Pseudomonas species strain NRRL-2994, Pseudomonas species strain NRRL B-3266, and baker's yeast. 10(R)-hydroxystearic acid isolated from Pseudomonas species strain NRRL-2994 was the standard for use in the H-nuclear magnetic resonance spectral technique to permit simple assignments of the absolute configurations of 10-hydroxystearic acid produced by different microorganisms. While the R. rhodochrous ATCC 12674-mediated hydration of oleic acid gave mixtures of enantiomers 10(R)-hydroxystearic acid and 10(S)-hydroxystearic acid, Pseudomonas species strain NRRL-B-3266 produced optically pure 10(R)-hydroxystearic acid. The remaining microorganisms stereoselectively hydrated oleic acid to 10(R)-hydroxystearic acid containing between 2 and 18% of the contaminating 10(S)-hydroxystearic acid.

18.
Appl Environ Microbiol ; 58(7): 2116-22, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1637152

RESUMEN

Resting cells of Saccharomyces cerevisiae (baker's yeast, type II; Sigma) were used to convert oleic acid into 10-hydroxyoctadecanoic acid with a 45% yield. Nocardia aurantia (ATCC 12674), Nocardia sp. (NRRL 5646), and Mycobacterium fortuitum (UI 53378) all converted oleic acid into 10-oxo-octadecanoic acid with 65, 55, and 80% yields, respectively. Structures of all metabolites were suggested by 1H and 13C nuclear magnetic resonance and by infrared and mass spectrometry. Structures of isomeric hydroxystearate and oxostearate derivatives and the stereochemical purity of hydroxystearates are difficult to prove unambiguously unless authentic standard compounds are available for spectral comparison. We describe the use of the chemical Baeyer-Villiger oxidation technique with 10-oxo-octadecanoic acid followed by mass spectral analysis of neutral extracts as a simple method to confirm the position of oxo-functional groups in the structures of fatty acid ketones. We further introduce a simple method based on 1H nuclear magnetic resonance analysis of diastereomeric S-(+)-O-acetylmandelate esters of hydroxystearates as a means of ascertaining stereochemical purities of hydroxy fatty acids.


Asunto(s)
Bacterias/metabolismo , Hongos/metabolismo , Ácidos Oléicos/metabolismo , Biotransformación , Esterificación , Espectroscopía de Resonancia Magnética , Mycobacterium/metabolismo , Nocardia/metabolismo , Ácido Oléico , Ácidos Oléicos/farmacocinética , Oxidación-Reducción , Saccharomyces cerevisiae/metabolismo , Ácidos Esteáricos/química , Ácidos Esteáricos/metabolismo
19.
Fundam Appl Toxicol ; 17(4): 684-95, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1778358

RESUMEN

Quinapril, an inhibitor of angiotensin-converting enzyme (ACE) and an antihypertensive agent, was evaluated in rats for effects on fertility, reproduction, and perinatal and postnatal development. In a fertility study, male rats were treated by gavage for 60 days prior to and during mating and female rats were treated by gavage for 14 days prior to mating, during mating and gestation, and during lactation with doses of 0, 10, 50, or 100 mg quinapril/kg body wt. There were no significant effects on body weight, food consumption, fertility indices, fetal development, or neonatal growth, survival, development, behavior, or reproduction. In a perinatal/postnatal study, administration of quinapril to females at doses of 25, 75, or 150 mg/kg during late gestation and lactation had no effects on parturition, lactation, or postnatal development, but a significant decrease in neonatal body weight during the suckling period was observed at all doses. In a subsequent study, female rats were given 150 mg/kg during late gestation, lactation, or late gestation and lactation. No adverse effects were seen in the dams or the offspring, and no reduction in neonatal body weight was observed. Kidneys from pups whose mothers received quinapril during gestation and/or lactation had minimal juxtaglomerular cell hypertrophy, characteristic of treatment with ACE inhibitors. Low levels of quinaprilat (the major and pharmacologically active metabolite of quinapril) were detected in fetal blood and in neonatal blood, indicating offspring exposure to quinapril. Milk quinaprilat concentrations were 3-5% of the plasma concentrations 3-5 hr after dosing. These studies demonstrate no adverse effects of quinapril on fertility, reproduction, or perinatal and postnatal development.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/toxicidad , Desarrollo Embrionario y Fetal/efectos de los fármacos , Fertilidad/efectos de los fármacos , Crecimiento/efectos de los fármacos , Isoquinolinas/toxicidad , Tetrahidroisoquinolinas , Inhibidores de la Enzima Convertidora de Angiotensina/farmacocinética , Animales , Animales Recién Nacidos/fisiología , Peso Corporal/efectos de los fármacos , Ingestión de Alimentos/efectos de los fármacos , Femenino , Isoquinolinas/farmacocinética , Riñón/patología , Lactancia/efectos de los fármacos , Masculino , Intercambio Materno-Fetal , Leche/metabolismo , Embarazo , Quinapril , Ratas , Ratas Endogámicas , Reflejo/efectos de los fármacos , Reproducción/efectos de los fármacos
20.
J Acoust Soc Am ; 90(3): 1355-70, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1939900

RESUMEN

Free-field release from masking was studied as a function of the spatial separation of a signal and masker in a two-interval, forced-choice (2IFC) adaptive paradigm. The signal was a 250-ms train of clicks (100/s) generated by filtering 50-microseconds pulses with a TDH-49 speaker (0.9 to 9.0 kHz). The masker was continuous broadband (0.7 to 11 kHz) white noise presented at a level of 44 dBA measured at the position of the subject's head. In experiment I, masked and absolute thresholds were measured for 36 signal source locations (10 degree increments) along the horizontal plane as a function of seven masking source locations (30 degree increments). In experiment II, both absolute and masked thresholds were measured for seven signal locations along three vertical planes located at azimuthal rotations of 0 degrees (median vertical plane), 45 degrees, and 90 degrees. In experiment III, monaural absolute and masked thresholds were measured for various signal-masker configurations. Masking-level differences (MLDs) were computed relative to the condition where the signal and mask were in front of the subjects after using absolute thresholds to account for differences in the signal's sound-pressure level (SPL) due to direction. Maximum MLDs were 15 dB along the horizontal plane, 8 dB along the vertical, and 9 dB under monaural conditions.


Asunto(s)
Atención , Dominancia Cerebral , Enmascaramiento Perceptual , Discriminación de la Altura Tonal , Adulto , Umbral Auditivo , Pruebas de Audición Dicótica , Femenino , Humanos , Masculino , Psicoacústica
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