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2.
Int J Impot Res ; 35(7): 672-678, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37179421

ABSTRACT

Surgical implantation of an inflatable penile prosthesis (IPP) remains the gold-standard treatment for severe erectile dysfunction. The ideal surgical technique requires a thorough understanding of the relevant anatomy. This includes anatomic considerations related to, but not limited to, dissection and exposure of penoscrotal fasciae and tissues, corporal configuration, and abdominal structures. Insights obtained from pre-dissected anatomic specimens can obviate urethral injury, nerve damage, corporal perforation, inappropriate sizing, crossover, or implant malposition. We present penile implant-specific anatomic dissections and topographic landmarks identified over the last decade in the course of surgical training programs provided for IPP implantation.


Subject(s)
Erectile Dysfunction , Penile Implantation , Penile Prosthesis , Male , Humans , Penile Implantation/methods , Erectile Dysfunction/surgery
4.
RSC Adv ; 8(7): 3646-3656, 2018 Jan 16.
Article in English | MEDLINE | ID: mdl-35542939

ABSTRACT

Small, spherical silver nanoclusters were synthesised on the surface of paper as a model cellulosic fibre substrate by a standard chemical reduction method. The concentration of the silver nanoclusters on the substrate surface is roughly proportional to the initial silver salt concentration. However, there is a noticeable degree of nanocluster aggregation to larger agglomerates. The addition of small amounts of α-cellulose, carboxymethyl cellulose or aminocellulose during the synthesis of the silver/cellulose nanocomposites suppresses this aggregation and significantly increases the concentration of the silver nanoclusters on the surface of the fibres of cellulose. These small, surface-stabilised silver nanoclusters, with the desired size and morphology, deposited from aqueous solutions on the surface of cellulosic cotton fibres, show enhanced antibacterial activity against MRSA compared to that of the corresponding silver/cotton nanocomposites prepared in the absence of a cellulosic surface stabiliser.

5.
Carbohydr Polym ; 89(3): 768-76, 2012 Jul 01.
Article in English | MEDLINE | ID: mdl-24750860

ABSTRACT

Xylan was isolated from birch wood chips by using pressurized hot water extraction (PHWE). The extracted xylan was chemically modified yielding three different xylan derivatives (XDs): xylan sulfate (XS), carboxymethyl xylan (CMX) and xylan-4-[N,N,N-trimethylammonium]butyrate chloride (XTMAB). The structure and molecular weight of XDs was determined by using NMR spectroscopy and size exclusion chromatography (SEC). The potential utilization of xylan polyelectrolytes for modifying fibre surfaces was assessed by sorption experiments using bleached pine Kraft pulp as substrate. Polyelectrolyte titration method was chosen for estimating the amount of sorbed XDs onto the fibres. The cationic xylan derivative XTMAB had a strong interaction with fibres while the anionic derivatives did not show any sorption. X-ray photoelectron spectroscopy (XPS) and time of flight secondary ion mass spectrometry (ToF-SIMS) were selected as advanced surface analyses for studying the amount of surface anionic groups and the surface distribution of the XTMAB. XPS and polyelectrolyte titration results suggested that the XTMAB is sorbed onto the fibre surfaces. ToF-SIMS imaging showed that XTMAB was evenly distributed on fibre surfaces.

6.
Protein Pept Lett ; 17(5): 578-84, 2010 May.
Article in English | MEDLINE | ID: mdl-19663804

ABSTRACT

Although cytoplasmic azoreductases have been purified and characterized from various bacteria, little evidence demonstrating that these azoreductases are directly involved in azo dye reduction in vivo is known. In order to evaluate the contribution of the enzyme to azo dye reduction in vivo, experiments were conducted to determine the effect of a recombinant cytoplasmic azoreductase (AzoA) from Enterococcus faecalis expressed in Escherichia coli on the rate of metabolism of Methyl Red, Ponceau BS and Orange II. The intact cells that contained IPTG induced AzoA had a higher rate of dye reduction with increases of 2 (Methyl Red), 4 (Ponceau BS) and 2.6 (Orange II)-fold compared to noninduced cells, respectively. Metabolites of Methyl Red isolated from induced cultures were identified as N,N-dimethyl-p-phenylenediamine and 2-aminobenzoic acid through liquid chromatography electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) analyses. In conclusion, our data demonstrate that AzoA from Ent. faecalis is capable of increasing the reduction of azo dyes in intact E. coli cells and that cytoplasmic azoreductase is involved in bacterial dye degradation in vivo.


Subject(s)
Azo Compounds/metabolism , Enterococcus faecalis/enzymology , Escherichia coli/metabolism , NADH, NADPH Oxidoreductases/biosynthesis , Anaerobiosis , Chromatography, Liquid , Enterococcus faecalis/genetics , Escherichia coli/enzymology , Escherichia coli/genetics , Isopropyl Thiogalactoside/metabolism , NAD/metabolism , NADH, NADPH Oxidoreductases/chemistry , NADH, NADPH Oxidoreductases/genetics , NADH, NADPH Oxidoreductases/metabolism , Nitroreductases , Spectrometry, Mass, Electrospray Ionization
7.
J Appl Microbiol ; 106(2): 564-71, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19200322

ABSTRACT

AIMS: To isolate environmental bacteria capable of transforming fluoroquinolones to inactive molecules. METHODS AND RESULTS: Bacteria were isolated from the aerobic liquor of a wastewater treatment plant on a medium containing norfloxacin (100 mg l(-1)). Twenty-two isolates were highly resistant (minimal inhibitory concentration: 6.25-200 microg ml(-1)) to five fluoroquinolones and six of them were positive by PCR amplification for the aminoglycoside resistance gene aac(6')-Ib. Of these, only Escherichia coli strain LR09 had the ciprofloxacin-acetylating variant gene aac(6')-Ib-cr; HPLC and mass spectrometry showed that this strain transformed both ciprofloxacin and norfloxacin by N-acetylation. This bacterium also had mutations in the quinolone-resistance determining regions of the gyrA and parC genes. CONCLUSIONS: An E. coli isolate from wastewater, which possessed at least two distinct fluoroquinolone resistance mechanisms, inactivated ciprofloxacin and norfloxacin by N-acetylation. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report of N-acetylation of fluoroquinolones by an aac(6')-Ib-cr-containing bacterium from an environmental source.


Subject(s)
Anti-Bacterial Agents/metabolism , Escherichia coli/isolation & purification , Fluoroquinolones/metabolism , Acetylation , Ciprofloxacin/pharmacology , Drug Resistance, Multiple, Bacterial , Escherichia coli/genetics , Escherichia coli/metabolism , Genes, Bacterial , Microbial Sensitivity Tests , Mutation , Norfloxacin/pharmacology , Waste Disposal, Fluid
8.
J Food Sci ; 72(2): C120-5, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17995826

ABSTRACT

Kava (Piper methysticum) extract products have been implicated in a number of severe hepatotoxicity cases. However, systematic toxicological studies regarding kava consumption have not been reported. In this study, 6 major kavalactones and different solvent fractions of kava roots, leaves, and stem peelings were evaluated for their mutagenic potential. None of the kavalactones was found to be positive in the experimental concentration ranges tested by the umu test (a sensitive test for point mutations). However, among the different solvent fractions, the n-butanol fraction of kava leaves was positive. Further investigations using bioassay-directed isolation and analysis indicated that 2 C-glycoside flavonoid compounds accounted for the positive mutagenic results. Two isolated compounds were identified as 2''-O-rhamnosylvitexin and schaftoside by NMR and MS techniques.


Subject(s)
Flavonoids/toxicity , Kava/chemistry , Monosaccharides/toxicity , Mutagenicity Tests , Plant Extracts/toxicity , Animals , Biological Assay , Chemical and Drug Induced Liver Injury , Flavonoids/isolation & purification , Glycosides , Monosaccharides/isolation & purification , Plant Leaves/chemistry , Plant Roots/chemistry , Plant Stems/chemistry , Point Mutation , Rats , Rats, Sprague-Dawley , Salmonella typhimurium/drug effects
9.
J Ind Microbiol Biotechnol ; 34(3): 219-24, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17186210

ABSTRACT

Mycobacterium sp. 7E1B1W and seven other mycobacterial strains known to degrade hydrocarbons were investigated to determine their ability to metabolize the piperazine ring, a substructure found in many drugs. Cultures were grown at 30 degrees C in tryptic soy broth and dosed with 3.1 mM N-phenylpiperazine hydrochloride; samples were removed at intervals and extracted with ethyl acetate. Two metabolites were purified from each of the extracts by high-performance liquid chromatography; they were identified by mass spectrometry and (1)H nuclear magnetic resonance spectroscopy as N-(2-anilinoethyl)acetamide and N-acetyl-N'-phenylpiperazine. The results show that mycobacteria have the ability to acetylate piperazine rings and cleave carbon-nitrogen bonds.


Subject(s)
Mycobacterium/metabolism , Piperazines/metabolism , Magnetic Resonance Spectroscopy , Spectrometry, Mass, Electrospray Ionization
10.
Magn Reson Chem ; 44(6): 594-605, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16568499

ABSTRACT

The processes of radical formation in N-methylmorpholine-N-oxide monohydrate (NMMO) and cellulose/NMMO solutions were studied by ESR at 77 K under high-power UV (lambda = 248 nm) excimer laser flash photolysis. Radicals mainly generated were attributed to the nitroxide type radicals -CH2-NO*-CH2- and -CH2-NO*-CH3 at the first step and methyl *CH3 and formyl *CHO radicals at the second step of the photoreaction. Kinetic studies of these radicals revealed that formation and recombination rates of the radicals depend on the cellulose concentration in cellulose/NMMO solutions and the concentration of additional ingredients, e.g. Fe(II) and propyl gallate. Even at frozen state temperature, acceleration or quenching of radical reaction processes was found. The proposed scheme of UV light-induced NMMO degradation during irradiation based on ESR data correlates well with independently obtained results based on high-performance liquid chromatography (HPLC). The analysis of degradation products by HPLC, e.g. aminoethanol and acetaldehyde, supports the assumption concerning a radical-initiated ring opening of NMMO.

11.
Z Geburtshilfe Neonatol ; 208(6): 226-31, 2004 Dec.
Article in German | MEDLINE | ID: mdl-15647986

ABSTRACT

INTRODUCTION: Maternal hyperglycemia during gestational diabetes leads to fetal hyperinsulinemia, which is associated with increased perinatal morbidity and mortality. Amniotic fluid insulin levels are therefore considered by some researchers to be ideal parameters to use in diagnosing gestational diabetes and making decisions about correct therapy. There are various recommendations about determining gestational diabetes early in pregnancy (< 24 weeks) by measuring amniotic fluid insulin. This study tests this association -- taking additional risk factors into account -- in a group of pregnant women who had genetic indications requesting for amniocentesis (AC). MATERIALS AND METHODS: All pregnant women who came to our clinic for genetically-determined amniocentesis from April 10, 1995 - Jan. 31, 2000 and who were between 12 and 24 weeks were included in our study. After a sample of amniotic fluid was taken, the laboratory performed a competitive radio-immuno-assay to determine the insulin concentration. O'Sullivan's cut-off values were used in diagnosing gestational diabetes. Since not all pregnant woman in our clinic were screened for gestational diabetes, we gathered our data retrospectively by checking all birth records; these were available in our clinic's data archive. RESULTS: A total of 483 pregnant women were included in our study. 22 (4.6 %) of them were classified as gestational diabetics. The average value for amniotic fluid insulin was 1.21 mU/L +/- 0.89. The insulin values for the entire study population exhibited a weekly increase of 0.1 mU/L from the 12th through the 24th week. The insulin concentrations for the 22 gestational diabetics were not significantly higher than those of the non-diabetics (1.05 mU/L vs. 1.0 mU/L; p = 0.34). In the 90 (th) percentile and above of the amniotic fluid insulin levels (2.2 mU/L) for the entire study population, the rate of gestational diabetics was at 11.8 % three times that of the non-diabetics, at 3.7 % (p = 0.021). Among the risk factors for gestational diabetes, an increased body mass index (BMI) value correlated significantly with increased insulin concentration (p < 0.001). The patients at and above the 90th percentile also had significantly higher BMI values (p = 0.002). In the multivariate analysis, the following influences were determined to be significant: maternal body mass index (p < 0.001) and the gestational age (p < 0,001), not the mere diagnosis of "gestational diabetes". A significant association was not found between elevated insulin values in amniotic fluid and the child's birth weight, APGAR values, pH-levels and blood glucose values. However, a significant association was found regarding fetal malformations and chromosome abnormalities. CONCLUSION: Even very low concentrations of insulin can be identified in amniotic fluid early in the pregnancy. The values increase during the course of the pregnancy. There is a positive correlation between maternal weight (BMI) and insulin levels in the amniotic fluid. Pregnant women with gestational diabetes have higher insulin levels in their amniotic fluid. The multivariant analysis shows, however, that this association can be traced to the maternal BMI and the time point during the pregnancy when the AC was performed. Malformations, especially those with a neural tube defect, are an additional cause for elevated insulin values in amniotic fluid.


Subject(s)
Amniotic Fluid/metabolism , Congenital Abnormalities/diagnosis , Congenital Abnormalities/epidemiology , Diabetes, Gestational/diagnosis , Diabetes, Gestational/epidemiology , Insulin/metabolism , Risk Assessment/methods , Adult , Comorbidity , Diabetes, Gestational/metabolism , Female , Germany/epidemiology , Glucose Tolerance Test/methods , Glucose Tolerance Test/statistics & numerical data , Humans , Pregnancy , Pregnancy Trimester, Second , Reproducibility of Results , Retrospective Studies , Risk Factors , Sensitivity and Specificity , Statistics as Topic
12.
Diabet Med ; 20(5): 349-54, 2003 May.
Article in English | MEDLINE | ID: mdl-12752482

ABSTRACT

AIMS: Fetal hyperinsulinism is a strong predictor for excessive growth and fetopathy in pregnancies complicated by diabetes. We examined (i). the relationship between measurements of amniotic fluid insulin (AF insulin) and fetal abdominal circumference (AC) at the time of amniocentesis, and (ii). whether there is a threshold for fetal AC percentiles which can identify low vs. high-risk levels of AF insulin without performing an amniocentesis. METHODS: In a retrospective study, AF insulin from 121 pregnant diabetic women (32 pregestational; 89 gestational) was measured during the 3rd trimester as part of a diabetes management protocol. AC measurements were transformed into a continuous variable of percentile growth for gestational age (Hadlock). Division of the cohort according to deciles or quartiles of AC percentiles was performed to identify a threshold AC with a significant increase in elevated AF insulin, previously defined as AF insulin >or= 7 microU/ml. A receiver operator characteristic (ROC) curve was created and the negative predictive value (NPV) of the determined threshold was calculated. RESULTS: AF insulin levels were significantly correlated with the AC percentiles (r = 0.3, P = 0.0005) by linear regression. No AC threshold could reliably identify a moderate elevated AF insulin >or= 7 microU/ml (NPV 77.2%), but an AC threshold >or= 75th percentile could identify with fetal hyperinsulinism with an AF insulin >or= 16 microU/ml. All 10 cases of AF insulin >or= 16 microU/ml were identified with a NPV of 100% (74/74). CONCLUSIONS: Our data indicate that an AC >or= 75th percentile determined by a 3rd trimester ultrasound examination may discriminate between pregnancies at low vs. high risk for AF insulin >or= 16 microU/ml. This AF insulin concentration corresponds to a level of hyperinsulinism reported to be associated with considerable neonatal and long term morbidity.


Subject(s)
Amniotic Fluid/metabolism , Hyperinsulinism/metabolism , Insulin/metabolism , Pregnancy in Diabetics/metabolism , Adult , Amniocentesis/methods , Body Weights and Measures , Cross-Sectional Studies , Female , Fetal Macrosomia/prevention & control , Gestational Age , Glucose Tolerance Test , Humans , Hyperinsulinism/mortality , Pregnancy , Pregnancy in Diabetics/diagnostic imaging , Retrospective Studies , Ultrasonography
13.
Z Geburtshilfe Neonatol ; 207(1): 12-6, 2003.
Article in German | MEDLINE | ID: mdl-12649781

ABSTRACT

BACKGROUND: Iodised salt was introduced in Germany in the early 1980s. A nation-wide study in 1996 showed that iodine levels among the population had improved since the introduction of the supplementation. The study did not separately investigate the iodine status of pregnant women. In our prospective study, we used three parameters to assess the iodine levels among pregnant women. PATIENTS AND METHODS: Between October 1999 and February 2000, we asked 109 German-speaking patients seeking prenatal care in our clinic to participate. Following informed consent, we measured goiter volume by ultrasound and collected venous blood (serum) and urine samples. We asked patients about any history of thyroid gland illnesses and about iodine supplementation which is generally given to pregnant patients in Germany. The blood and urine samples were stored at -18 degrees C until measurement. We used the iodine-creatinine-ratio to measure ioduria. Iodine was measured using the Cer-Arsenite-method (Dade-Behring). The thyroglobulin concentration in serum was measured using RIA. RESULTS: The mean iodine-creatinine ratio was 181 +/- 109 microg/g, 20.4 % of the patients had a ratio between 50 and 100 microg/g which is defined as iodine deficiency I degrees (WHO). 8.7 % of the patients had thyreoglobulin levels above the cut-off value of 50 ng/ml. 12.6 % of the patients had a goiter (volume > 18 ml). 58 % of the patients were taking iodine supplements. These patients had significantly higher iodine-creatinine ratio levels (204 microg/g vs. 148 microg/g, P = 0.007) and lower serum thyroglobulin levels (38.4 vs. 34.1 pmol/l, P = 0.06) than non-supplemented patients. CONCLUSIONS: The prevalence of goiter reflects an extended period of iodine deficiency. Using laboratory methods, up to 20.4 % of pregnant women were identified as having an iodine deficiency which indicates the need for a general iodine supplementation during pregnancy.


Subject(s)
Goiter, Endemic/epidemiology , Iodine/deficiency , Pregnancy Complications/epidemiology , Adult , Berlin/epidemiology , Cross-Sectional Studies , Female , Goiter, Endemic/etiology , Goiter, Endemic/prevention & control , Humans , Infant, Newborn , Iodine/administration & dosage , Nutrition Surveys , Nutritional Requirements , Pregnancy , Pregnancy Complications/etiology , Pregnancy Complications/prevention & control , Prospective Studies , Risk , Sodium Chloride, Dietary/administration & dosage
14.
Appl Microbiol Biotechnol ; 56(3-4): 474-7, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11549022

ABSTRACT

The metabolism of the fluoroquinolone drugs ciprofloxacin and norfloxacin by Pestalotiopsis guepini strain P-8 was investigated. Cultures were grown at 28 degrees C in sucrose/peptone broth for 18 days after dosing with ciprofloxacin (300 microM) or norfloxacin (313 microM). Four major metabolites were produced from each drug; and these were purified by high-performance liquid chromatography and identified by mass spectrometry and proton nuclear magnetic resonance spectroscopy. Ciprofloxacin metabolites included N-acetylciprofloxacin (52.0%), desethylene-N-acetylciprofloxacin (9.2%), N-formylciprofloxacin (4.2%), and 7-amino-1-cyclopropyl-6-fluoro-4-oxo-1,4-dihydroquinoline-3-carboxylic acid (2.3%). Norfloxacin metabolites included N-acetylnorfloxacin (55.4%), desethylene-N-acetylnorfloxacin (8.8%), N-formylnorfloxacin (3.6%), and 7-amino-1-ethyl-6-fluoro4-oxo-1,4-dihydroquinoline-3-carboxylic acid (2.1%). N-Formylciprofloxacin and the four transformation products from norfloxacin are all known to be mammalian metabolites.


Subject(s)
Anti-Infective Agents/metabolism , Ciprofloxacin/metabolism , Fungi/growth & development , Norfloxacin/metabolism , Biodegradation, Environmental , Chromatography, High Pressure Liquid , Culture Media, Conditioned/chemistry , Fungi/metabolism , Magnetic Resonance Spectroscopy
16.
Xenobiotica ; 31(11): 799-809, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11765142

ABSTRACT

1. To determine the ability of fungi to metabolize sulphur- and oxygen-containing azaarenes, Cunninghamella elegans ATCC 9245 was grown in 125-ml flasks containing fluid Sabouraud medium. The cultures and controls were incubated at 28 degrees C with shaking and dosed with 16.7 mM phenothiazine or phenoxazine. After incubation for 72h, the mycelia and filtrates were extracted with ethyl acetate and the combined residues analysed by high-performance liquid chromatography. Residual phenothiazine and phenoxazine were 21 and 22%, respectively, of the total UV absorbance at 254 nm. 2. The metabolites were identified by mass spectrometry and proton nuclear magnetic resonance spectroscopy. The fungus oxidized phenothiazine to phenothiazine sulphoxide, 3-hydroxyphenothiazine sulphoxide, phenothiazin-3-one, and 3-hydroxyphenothiazine and oxidized phenoxazine to phenoxazin-3-one. 3. Three of the four compounds produced by C. elegans from phenothiazine were identical to those produced by mammals, supporting the use of the fungus as a microbial model for drug metabolism.


Subject(s)
Cunninghamella/metabolism , Oxazines/metabolism , Phenothiazines/metabolism , Chromatography, High Pressure Liquid , Oxidation-Reduction , Spectrophotometry, Ultraviolet , Sulfoxides/metabolism
17.
Biomacromolecules ; 2(4): 1124-32, 2001.
Article in English | MEDLINE | ID: mdl-11777383

ABSTRACT

A variety of new cellulose solvents was investigated toward their potential as media for the functionalization of the polyglucane. Thus, mixtures of dimethyl sulfoxide (DMSO)/tetrabutylammonium fluoride trihydrate (TBAF), N-methylmorpholine-N-oxide (NMMNO)/DMSO, melts of LiClO(4).3H(2)O, and aqueous solutions of Ni(tren)(OH)(2) [tren = tris(2-aminoethyl)amine] were applied as reaction media. In case of the new solvent, DMSO/TBAF its usefulness for derivatization reactions including the etherification with sodium monochloroacetate and the acylation with vinyl esters of carbonic acids was studied. The structural features of the products were analyzed by means of (1)H NMR spectroscopy (after depolymerization or peresterification), (13)C NMR spectroscopy, and HPLC after complete hydrolytic chain degradation. The results were compared with those obtained from derivatives prepared using the solvent N,N-dimethylacetamide (DMAc)/LiCl and conventional, heterogeneous synthesis. It can be shown that in case of carboxymethylation reactions the reaction medium applied has a drastic influence both on the course of reaction and on the structural features of the products. A highly efficient tool was found to be atomic force microscopy (AFM), showing remarkable differences in the superstructures of the differentially synthesized derivatives.


Subject(s)
Carboxymethylcellulose Sodium/chemical synthesis , Cellulose/analogs & derivatives , Cellulose/chemical synthesis , Acetylation , Carbohydrate Conformation/drug effects , Carboxymethylcellulose Sodium/chemistry , Cellulose/chemistry , Dimethyl Sulfoxide/chemistry , Microscopy, Atomic Force , Quaternary Ammonium Compounds/chemistry , Solvents/pharmacology
18.
J Chromatogr A ; 888(1-2): 85-92, 2000 Aug 04.
Article in English | MEDLINE | ID: mdl-10949475

ABSTRACT

A RP-HPLC method with photodiode array detection and LC-electrospray ionization (ESI) MS confirmation was established for the determination of major active components in St. John's Wort dietary supplement capsules. The samples alternatively were extracted with ethanol-acetone (2:3) using a 55 degrees C water-bath shaker or an ambient temperature ultrasonic bath. Extracts were separated by RP-C18 chromatography using a 95-min water-methanol-acetonitrile-trifluoroacetic acid gradient. The major components were identified by photodiode array detection and then confirmed by LC-ESI-MS. The quantification of components was performed using an internal standard (luteolin). This method may serve as a valuable tool for the quality evaluation of St. John's Wort dietary supplement products.


Subject(s)
Chromatography, High Pressure Liquid/methods , Dietary Supplements/analysis , Hypericum/chemistry , Plants, Medicinal , Calibration , Reproducibility of Results , Spectrometry, Mass, Electrospray Ionization , Spectrophotometry, Ultraviolet
19.
Appl Environ Microbiol ; 66(8): 3646-9, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10919836

ABSTRACT

We examined Cunninghamella elegans to determine its ability to transform amoxapine, a tricyclic antidepressant belonging to the dibenzoxazepine class of drugs. Approximately 57% of the exogenous amoxapine was metabolized to three metabolites that were isolated by high-performance liquid chromatography and were identified by nuclear magnetic resonance and mass spectrometry as 7-hydroxyamoxapine (48%), N-formyl-7-hydroxyamoxapine (31%), and N-formylamoxapine (21%). 7-Hydroxyamoxapine, a mammalian metabolite with biological activity, now can be produced in milligram quantities for toxicological evaluation.


Subject(s)
Amoxapine/metabolism , Antidepressive Agents, Second-Generation/metabolism , Cunninghamella/metabolism , Biotransformation , Chromatography, High Pressure Liquid , Cunninghamella/growth & development , Magnetic Resonance Spectroscopy , Mass Spectrometry
20.
Rapid Commun Mass Spectrom ; 14(10): 911-7, 2000.
Article in English | MEDLINE | ID: mdl-10825256

ABSTRACT

Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectra of bacterial proteins were obtained from water, lettuce and cloth samples contaminated with Shigella flexneri, Escherichia coli, and Aeromonas hydrophila. Spectra were obtained using proteins directly isolated from water (or water used for rinsing samples) without culturing the bacteria. For S. flexneri and E. coli, two marker ions for specific proteins associated with a virulence-related property (acid resistance) were easily detected. For A. hydrophila, ions from two specifically selected marker proteins, as well as ions from the larger group of proteins isolated from pure cultures, all matched spectra from a contaminated water sample, providing strong evidence that A. hydrophila was the bacterial contaminant. Rinse water from contaminated lettuce and cloth samples showed the same marker ions as the contaminated water samples.


Subject(s)
Bacterial Proteins/analysis , Food Microbiology , Gossypium/microbiology , Lactuca/microbiology , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Water Microbiology , Aeromonas hydrophila/isolation & purification , Biomarkers/analysis , Escherichia coli/isolation & purification , Ions , Lasers , Shigella flexneri/isolation & purification
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