When Victor Hensen deployed the first true plankton net in 1887, he and his colleagues were attempting to answer three fundamental questions: What planktonic organisms are present in the ocean? How many of each type are present? How does the plankton’s composition change over time? Although answering these questions has remained a central goal of oceanographers, the sophisticated tools availabl...

The growing threat of biological agents, new diseases, and food-borne pathogens has created an increasing need for rapid and sensitive detection before the target population becomes infected. The incident of the anthrax letters in October 2001, the emergence of Severe Acute Respiratory Syndrome (SARS) and the West Nile virus, and repeated occurrences of food-borne pathogens illustrate how neces...

During a 2-month period, 62 strains of Haemophilus ducreyi were isolated from 168 genital lesions and 2 lymph node aspirates. Of these strains, 22 were found on both chocolate agar and fetal bovine serum agar supplemented with vancomycin, 29 were found only on chocolate agar, and 9 were found only on fetal bovine serum agar. Two additional strains were isolated on sheep blood agar. All of these...

Mono-specific antisera against Vibrio cholera Ogawa NIH-43 and Vibrio cholera Inaba 35-A3 were prepared from rabbit hyperimmune sera by absorbing against a heterologous strain. Using ammonium sulphate precipitation procedure, gamma globulins were purified and concentrated. To visualize antigen-antibody reaction, gamma globulins were conjugated to Staphylococcus aureus cowan-l (NCTC: 8325) ...

In a clinical trial a new pyrrolidonyl-β-naphthylamide (PYR) hydrolysis test was compared with the bacitracin disk susceptibility test for accuracy in the presumptive identification of group A streptococci (GAS). Among 128 isolates of beta-hemolytic streptococci 93 group A isolates were found. The sensitivity of the PYR and bacitracin tests were similar (98.9%), but the bacitracin test had ...

Rapid microbiologic tests provide opportunities for antimicrobial stewardship programs to improve antimicrobial use and clinical and economic outcomes. Standard techniques for identification of organisms require at least 48-72 hours for final results, compared with rapid diagnostic tests that provide final organism identification within hours of growth. Importantly, rapid microbiologic tests ar...

A total of 706 yeast isolates were evaluated in parallel by the Candida albicans Screen (CAS; Carr-Scarborough Microbiologicals, Inc., Stone Mountain, Ga.) test and the germ tube (GT) test in comparison with the API 20C Yeast Identification System. The CAS and GT tests correctly identified 419 of the 422 isolates of C. albicans (99.3%). Two of the false-negative reactions occurring with the CAS...

We describe a new approach for infectious disease surveillance that facilitates rapid identification of known and emerging pathogens. The process uses broad-range polymerase chain reaction (PCR) to amplify nucleic acid targets from large groupings of organisms, electrospray ionization mass spectrometry for accurate mass measurements of PCR products, and base composition signature analysis to id...

The fatty acid constituents of 14 species of Mycobacterium (14 isolates) and one isolate each of Corynebacterium xerosis, Nocardia asteroides, and Streptomyces albus were examined with the purpose of distinguishing Mycobacterium tuberculosis from other acid-fast bacilli. Combined thin-layer chromatography (TLC) of methyl mycolates and gas-liquid chromatography (GLC) of shorter-chain fatty acid ...