Search Results - (Author, Cooperation:Shriniwas)

1573-7284

Pseudomonas aeruginosa ; Protease ; Elastase ; Aeruginocine typing

Springer Online Journal Archives 1860-2000

Medicine

Abstract Sixty six consecutive P. aeruginosa isolates from heterogeneous clinical specimens were subjected to aeruginocine (pyocine) typing and assayed for in vitro protease and elastase production by a simple and reproducible qualitative test. The 45.4% of the clinical isolates were found to be both protease and elastase (P + E +) producers; 40.9% were only protease producers (P + E −) and 13.6% were non producers (P− E t-). Aeruginocine code 7777 strains were found to be predominant among P + E + and P+ E− types, as 48.2% and 51.7% isolates belonged to the types, respectively, suggesting thereby the virulence of this aeruginocine type in P. aeruginosa infections and the possible association of protease and elastase production with aeruginocine production.

Electronic Resource

1573-2630

aeruginocin typing ; experimental keratitis ; bacterial corneal ulcers ; Pseudomonas aeruginosa ; corneal pathogenicity

Springer Online Journal Archives 1860-2000

Medicine

Abstract Fifty strains of Pseudomonas aeruginosa isolated from human eyes were aeruginocin typed by the method of Shriniwas (1974) using ten indicator strains. These belonged to types A1 (3), B (2), F1 (1) and 14 (1). Fifteen (30.0%) were nontypable and 28 (56.0%) were unclassifiable presenting twenty inhibition patterns. The strains showed a wide range of antibiotic sensitivities. The highest number of insensitive strains were those obtained from corneal ulcers. Experimental keratitis produced by strains of pseudomonas was either mild, moderate or severe and was unrelated to their source. Mild keratitis was produced by types UC 7-, UC 79- and 14 isolated from pre-operative, corneal ulcer and post-operative patients. Lesions of moderate severity were produced by types 189#x002B; & A1 whereas the severest pathology was produced by UC 23478-, B and UC 810- types. The fact that strain 23478- always produced severest pathology irrespective of whether originated from group I, II, or IV strongly suggests relationship of pathogenicity with aeruginocin type.

Electronic Resource

1573-0832

Barley ; Deoxynivalenol ; Fusarium graminearum ; Mycotoxins ; Trichothecenes ; Zearalenone

Springer Online Journal Archives 1860-2000

Biology

Medicine

Abstract Twelve isolates ofFusarium graminearum were obtained from barley grains collected from different Uruguayan regions (harvest 1993–94). This was the predominant fungal species contaminating the crop due to a particular humid and warm season with cold nights conducive to toxin production The isolates were grown on moist, sterile rice, extracted with aqueous methanol, and examined for mycotoxin production. Zearalenone (ZEA) and the trichothecenes deoxynivalenol (DON), 3- and 15-acetyl-DON (AcDON), nivalenol (NIV), fusarenon-X (FX) and T-2 toxin (T-2) were analyzed by thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC) and confirmed by gas chromatography-mass spectrometry (GC-MS). Eleven of the 12 strains were DON and/or ZEA producers and 9 were AcDON positive. No NIV, or FX were detected. One strain produced T-2. The predominant acetyl-DON isomer was 15-AcDON. Mass-spectral analysis yielded detectable levels of other mycotoxins, 13-OH-apotrichothecenes, 11-epiapotrichothecenes, culmorin, sambucinol, and isotrichodermol being the most numerous. From the metabolic profiles it is suggested that UruguayanF. graminearum strains belong to the chemotype IB (DON/15-AcDON). The predominance of this chemotype is in accordance with data from Canada, United States, Mexico and Argentina which have similar climatic conditions that would favorF. graminearum growth and mycotoxin production.

Electronic Resource

0001-1541

Chemistry ; Chemical Engineering

Wiley InterScience Backfile Collection 1832-2000

Chemistry and Pharmacology

Process Engineering, Biotechnology, Nutrition Technology

A modified CaCO3 sorbent with an open internal pore structure is prepared and its sulfation characteristics are investigated in an entrained flow reactor at high temperatures (900-1,100°C) and short contact times (20-600 ms) using small particle sizes (〈 5 μm). The most distinguishing feature of this modified carbonate (MC) is its 70-75% sulfation conversion within 0.5 s, which is substantially higher than any other sorbents published. The MC is prepared by carbonation-precipitation from a calcium hydroxide suspension by optimizing the operating parameters to generate carbonate particles of the desired pore structural properties. The high initial surface area combined with its open pore structure and pore-size distribution of its calcine contribute to its high reactivity. The calcined MC possesses a significant portion of its pore volume in the 50-200 Å range. This size range represents an optimum pore size for sulfation since it provides a reasonably high surface area and is less susceptible than 〈 50 Å pore sizes, to pore filling, or pore-mouth plugging due to the formation of higher molar volume CaSO4. Investigation with other carbonates reveals that a much higher portion of their calcines' porosity lies in the smaller pores, which leads to premature termination of sulfation. Results show the impact of internal pore structure on initial reactivity and ultimate sorbent conversion.

17 Ill.

Electronic Resource

2018-01-12

Wiley-Blackwell

1097-4652

Biology

Medicine