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M A Pisano

Publications and source records attributed to M A Pisano.

At least 19 recordsLinked to original sources
PubMed1995

Validation of a bacteremia prediction model.

OBJECTIVE: To validate a previously published model for predicting bacteremia in hospitalized patients. DESIGN: Application of a published bacteremia prediction model to a prospective validation cohort of patients and comparison of its predictability to that found in the derivation cohort. SETTING: Urban, university-affiliated, 550-bed public hospital. PATIENTS: The validation cohort consisted of 342 patients with 559 blood culture episodes between October 14, 1992, and December 5, 1992. Each blood culture episode was scored based on the presence or absence of seven predictors of bacteremia and the findings compared with published results (derivation cohort). INTERVENTIONS: None. RESULTS: Application of the bacteremia prediction model to the validation cohort identified episodes with a low risk (3%) and a high risk (17%) for true bacteremia, similar to the findings in the derivation cohort (1% and 16%, respectively). Comparison of the predictions of the model in the two cohorts by receiver operator characteristic curve analysis revealed that the overall predictability of the model in the validation cohort was not as good as in the derivation cohort. CONCLUSIONS: Although the bacteremia prediction model did not perform as well overall in the validation cohort, the model still was able to clearly define two extreme groups: those with a low risk and those with a high risk for true bacteremia. This predictive capability may aid physicians in prescribing empiric antimicrobial therapy and also may be useful to hospital epidemiologists in assessing quality of care.

Adolescent↗
PubMed1988

Gas-liquid chromatographic analysis of fatty acid methyl esters of Aeromonas hydrophila, Aeromonas sobria, and Aeromonas caviae.

Clinical isolates of Aeromonas hydrophila, A. sobria, and A. caviae whose fatty acid content had been analyzed by gas-liquid chromatography (GLC) displayed the following qualitatively similar GLC profiles: 12:0, 14:0, 15:0, 16:0, 17:0, 18:0, 16:1, 18:1, a-15:0, a-17:0, and 3-OH 14:0. The 16:0/17:0 area-percentage ratio separated the clinical aeromonads in accordance with their species designations. Aeromonads treated with subminimal inhibitory concentrations of the antibiotic cerulenin displayed the following altered qualitative fatty acid GLC profiles: 12:0, 14:0, 16:0, 18:0, 16:1, 18:1, and 3-OH 14:0. Cerulenin-treated cells failed to reproducibly display detectable levels of all odd-numbered-carbon-chain-length fatty acids observed in untreated cells. Cerulenin-treated cells also exhibited overall increases in 14:0 and 3-OH 14:0 and a decrease in total unsaturated fatty acid content.

Aeromonas↗
PubMed1986

Enzyme-linked immunosorbent assay for detection of streptolysin O antibodies.

An enzyme-linked immumosorbent assay (ELISA), based upon the detection of streptolysin O antibodies in human sera, was developed. Disposable polystyrene tubes, sensitized with streptolysin O antigen, were used as the test vehicles. Corresponding antibodies, present in test sera, were detected by binding of the antibodies to goat anti-human immunoglobulin G conjugated to horseradish peroxidase. Demonstration of bound conjugate was accomplished by monitoring peroxidase activity spectrophotometrically at 450 nm, using 5-aminosalicylic acid as the indicator. A total of 97 human sera, previously analyzed by means of the anti-streptolysin O titration technique, were evaluated with the ELISA procedure. A direct quantitative relationship, found to be statistically significant, was demonstrated between Todd units and absorbance values obtained with ELISA.

Antibodies, Bacterial↗
PubMed1984

Changes in the lipid composition of Paecilomyces persicinus P-10 M1 during growth and cephalosporin C production.

The lipid composition of the fungus Paecilomyces persicinus P-10 M1 was monitored daily for 6 days to detect any changes during growth and cephalosporin C production. Total lipid yields and cephalosporin C production were maximal after 72 h of incubation. Analysis of the total lipids revealed that the neutral lipid fraction was elevated at this time, whereas polar lipids were depressed. Phosphatidylethanolamine and phosphatidylcholine represented the major phospholipids detected. Phosphatidylethanolamine levels were descending when cephalosporin C was detected at its highest concentration. Increases in phosphatidylcholine levels paralleled those of cephalosporin C but reached a maximum at 48 h after the latter. Diphosphatidylglycerol, phosphatidic acid, and phosphatidylserine were also detected. Fatty acids present in the total lipid fraction ranged in carbon length from C12 to C24. The major acids were C16 (palmitic), C18:1 (oleic), and C18:2 (linoleic). All fatty acids exhibited minor variations in concentration during the 6-day period, and none displayed a direct correlation with cephalosporin C yields.

Cephalosporins↗
PubMed1983

Partial characterization of Yersinia intermedia bacteriocin.

Yersinia intermedia produces a temperature-dependent (25 degrees C) bactericidal substance that is active against other Yersinia species. Crude preparations of the inhibitory substance were inactivated by chymotrypsin, trypsin, pronase, and heating but were not affected by lipolytic enzymes, chloroform, or other organic solvents. These data suggest that the active molecule is a bacteriocin of a proteinaceous nature. The molecular weight of the bacteriocin was estimated to be greater than 14,000. Exposure of agar fragments containing the active component to a pH range of 3 to 11 did not affect bactericidal activity. Bactericidal activity against the Y. frederiksenii indicator strain was shown by simultaneous and deferred antagonism and by the associative culture technique. The liquor from cell-free macerated agar fragments and broth cultures, however, were devoid of antibacterial activity.

Bacteriocins↗
PubMed1983

Temperature-related variations in the lipid composition of methicillin-resistant and methicillin-susceptible Staphylococcus aureus strains.

Growth of methicillin-susceptible and -resistant strains of Staphylococcus aureus at 28 and 37 degrees C led to changes in the relative amounts of phospholipids recovered. The major phospholipids present in these strains were phosphatidylglycerol, lysophosphatidylglycerol, and diphosphatidylglycerol. Phosphatidylglycerol tended to occur in lower amounts in the resistant strains, but it was the major phospholipid in both methicillin-susceptible and -resistant S. aureus strains. Growth patterns and total lipid concentrations were similar in all strains.

Methicillin↗
PubMed1982

Synthesis and antimicrobial activity of triorganotin 5-nitro-2-furoates.

Five triorganotin 5-nitro-2-furoates were synthesized by reacting 5-nitro-2-furoic acid with either the corresponding bis(triorganotin) oxide or the corresponding triorganotin hydroxide. The IR spectrum of each compound was obtained over the 4000--200-cm-1 range, and some of the bands were assigned. One compound, tri-n-butyltin 5-nitro-2-furoate, was an excellent antifungal agent, completely inhibiting the growth of six of ten test fungi at a concentration of 1 microgram/ml. The new compounds were also investigated for antibacterial activity and were especially inhibitory toward Gram-positive species. Two of the compounds completely inhibited the Gram-negative bacterium Escherichia coli at a concentration of 100 microgram/ml.

Bacteria↗
PubMed1982

Changes in cell wall carbohydrate composition of Paecilomyces persicinus P-10 M1 during growth and cephalosporin C production.

The carbohydrate composition of the cell walls of Paecilomyces persicinus P-10 M1 was monitored daily for 6 days to detect any changes during growth and cephalosporin C production. Walls were isolated after mechanical breakage, sonication, and exposure to detergent. Major quantitative changes in cell wall carbohydrate composition accompanied a decrease in both cell weight and antibiotic production. Glucosamine content remained relatively constant in the 24- to 96-h cell walls and increased markedly in the 120- and 144-h preparations. The non-nitrogenous carbohydrate cell wall component, however, decreased significantly in the 48- and 120-h cell walls. Gas-liquid chromatographic analysis of the non-nitrogenous carbohydrate cell well fraction revealed the presence of glucose, the major component, mannose, galactose, and minute quantities of arabinose. Except for glucose, which was found to decrease moderately in the 120- and 144-h cell walls, the neutral sugars did not vary significantly with time.

Carbohydrates↗
PubMed1982

Isolation and characterization of Phycomyces blakesleeanus ferritin.

Ferritin was isolated from the fungus Phycomyces blakesleeanus and compared biochemically and immunologically with horse spleen ferritin. Phycomyces and horse spleen ferritins were shown to exhibit similar electrophoretic patterns on polyacrylamide gels. Both preparations yielded an identical single band on sodium dodecyl sulfate-containing polyacrylamide gels. Tryptic digests of Phycomyces ferritin yielded 17 ninhydrin-positive spots as compared to 26 for horse spleen ferritin tryptic digests. Phycomyces ferritin was immunologically unrelated to horse spleen ferritin.

Animals↗
PubMed1980

Antimicrobial activity of N-substituted N-(triphenylstannyl)cyanamides and triethylammonium (organocyanoamino)chlorotriphenylstannates.

N-Substituted N-(triphenylstannyl)cyanamides were studied and found to be better antifungal agents than the previously tested N-substituted N'-cyano-S-(triphenylstannyl)isothioureas and N-substituted N'-cyano-O-(triphenylstannyl)isoureas. They were similar in activity to the previously tested ethyl N-aryl-S-(triphenylstannyl)-isothiocarbamates. The antifungal activity of triethylammonium (organocyanoamino)chlorotriphenylstannates, which are the triethylammonium chloride complexes of N-substituted N-(triphenylstannyl)-cyanamides, was similar to or better than that of the N-substituted N-(triphenylstannyl)cyanamides. Triethylammonium (acetylcyanoamino)chlorotriphenylstannate and triethylammonium dichlorotriphenylstannate were highly inhibitory toward Gram-positive bacteria.

Anti-Bacterial Agents↗
PubMed1979

Isolation and nature of intracellular alpha-aminoadipic acid-containing peptides from Paecilomyces persicinus P-10.

Small intracellular peptides containing alpha-aminoadipic acid, cysteine, and a valine moiety were obtained from mycelia of Paecilomyces persicinus P-10 by ethanol or trichloroacetic acid extraction. After performic acid oxidation and ion-exchange chromatography, analysis of the peptide fractions by two-dimensional thin-layer electrophoresis and chromatography revealed the presence of three related peptides, as sulfonic acid derivatives, each containing alpha-aminoadipic acid. Each peptide was isolated in chromatographically pure form by semipreparative thin-layer electrophoresis and chromatography. The purified peptides were subjected to differential hydrolysis, dansylation, and combined dansylation-phenylisothiocyanate sequence analysis. Based on these studies, the structures of the isolated peptides were determined to be (i) glycl-delta-(alpha-aminoadipyl)-cysteinyl-beta-hydroxyvaline, (ii) glycyl-delta-(alpha-aminoadipyl)-cysteinylvaline, and (iii) delta-(alpha-aminoadipyl)-cysteinylvaline. The peptides isolated from Paecilomyces are similar to the alpha-aminoadipic acid-cysteine-valine moiety complex peptides isolated from Cephalosporium.

2-Aminoadipic Acid↗
PubMed1979

Purification and characterization of an extracellular beta-n-acetylhexosaminidase from Paecilomyces persicinus.

Both beta-N-acetylglucosaminidase nad beta-N-acetylgalactosaminidase activities were detected in the culture fluids of Paecilomyces persicinus P-10 after growth in a soybean meal-corn meal medium. The active material was purified by means of protamine sulfate fractionation and ultrafiltration, followed by ion exchange and gel chromatography. The ratio of the two activities remained constant throughout the purification, and the final product was shown to migrate as a single band by using gel isoelectric focusing, disc electrophoresis, and detergent gel electrophoresis. Temperature, pH, inhibition, and kinetic studies were performed to characterize both activities. The molecular weight of the enzyme was estimated to be about 100,000 by high-resolution gel chromatography. Based on the data obtained, it is suggested that both beta-N-acetylglucosaminidase and beta-N-acetylgalactosaminidase activities reside in the same protein.

Acetylglucosaminidase↗
PubMed1979

Yersinia intermedia: temperature-dependent bacteriocin production.

Yersinia enterocolitica and related Yersinia species share many temperature-dependent biological attributes. The present report documents temperature-dependent production of a bacteriocin-like substance only among Yersinia strains which ferment L-rhamnose, raffinose, and melibiose and which have been tentatively designed Y. intermedia. When tested by the "lawn-spotting" technique at 25 and 37 degrees C, 7 of 15 Y. intermedia strains produced a bacteriocin only at 25 degrees C with a uniform spectrum of activity against 2 strains of Y. enterocolitica, 1 rhamnose-positive, raffinose-negative, melibiose-negative strain tentatively designated Y. frederiksenii, 8 Y. intermedia, and 3 sucrose- and acetylmethylcarbinol-negative yersinial isolates tested. Bacteriocin-like activity was not detected among the Y. enterocolitica, Y. frederiksenii, or sucrose-negative yersinial strains tested. The exclusive activity of the Y. intermedia antibacterial substance only against yersiniae and not against other representative Enterobacteriaceae tested supports the placement of these microorganisms within the genus Yersinia and further establishes the singularity of Y. intermedia.

Bacteriocins↗
PubMed1978

Synthesis and antimicrobial activity of ethyl N-aryl-S-(triphenylstannyl)isothiocarbamates.

Five ethyl N-aryl-S-(triphenylstannyl)isothiocarbamates were synthesized by the reaction of triphenyltin iodide with the appropriate ethyl N-arylthiocarbamate in the presence of triethylamine. The IR spectrum of each compound was obtained over the 4000--200-cm--1 range, and some bands were assigned. These new compounds were found to be generally better antifungal agents than the previously tested N-substituted N'-cyano-S-(triphenylstannyl)isothioureas. The new compounds were also investigated for antibacterial activity and were especially inhibitory toward Gram-positive species. Except for their lower activity toward Bacillus subtilis, their antibacterial activity was identical to the previously tested N-phenyl-N'-cyano-S-(triphenylstannyl)isothiourea.

Anti-Bacterial Agents↗
PubMed1977

The effect of temperature on the fatty acid and phospholipid composition of Cephalosporium falciforme and Cephalosporium kiliense.

The effect of temperature on the lipid composition of Cephalosporium falciforme and Cephalosporium kiliense, causative agents of maduromycosis, was investigated. The fungi were grown at 28.5 C and 37 C in a chemically defined medium. The lipids were solvent extracted, purified on Sephadex, and separated into their component classes by silicic acid column chromatography. Five lipid classes were found: (a) sterol esters, (b) triacylglycerides, (c) free fatty acids, (d) sterols, and (e) phospholipids. Fatty acids were analyzed by gas liquid chromatography. Temperature induced changes of varying degrees occurred in both the fatty acid and phospholipid fractions of each organism.

Acremonium↗
PubMed1976

A chemically defined medium for cephalosporin C production by Paecilomyces persicinus.

A chemically defined medium was developed for the biosynthesis of cephalosporin C by Paecilomyces persicinus Nicot strain P-10. Glucose served as the major carbon source and nitrogen was supplied by five amino acids, L-arginine, L-aspartic acid, L-glutamic acid, glycine and DL-methionine. Omission of any of the first four diminished or prevented production of cephalosporin C; omission of methionine did not. Methionine is not critical for the production of cephalosporin C in this defined medium. Production of the antibiotic was affected by the concentrations of inorganic salts employed. Biotin was required for growth and cephalosporin C synthesis. The addition of L-lysine precursors to the medium did not influence cephalosporin C levels and L-lysine itself inhibited antibiotic production. Known precursors of beta-lactam antibiotics as well as oleic acid did not affect biosynthesis of cephalosporin C. Chemical changes occurring in the defined medium revealed that glucose was efficiently utilized after 96 hours incubation whereas total soluble nitrogen levels increased following an initial sharp decrease. Mycelial weight and cephalosporin C production were both maximal after 96 hours incubation. Mycelial nitrogen was highest after 48 hours incubation whereas mycelial lipid levels were greatest after 72 hours.

Arginine↗