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L F Freundlich

Publications and source records attributed to L F Freundlich.

At least 19 recordsLinked to original sources
PubMed1994

Restriction fragment length polymorphism analysis of Cryptococcus neoformans isolates from environmental (pigeon excreta) and clinical sources in New York City.

Restriction fragment length polymorphism analysis of environmental (pigeon excreta) and clinical Cryptococcus neoformans var. neoformans isolates in a limited geographic area distinguished 6 strains among 8 environmental isolates and 12 strains among 17 clinical isolates. Clusters of patients with three strains types accounted for 47% of clinical isolates. Despite this diversity, two strains were shared by environmental and clinical isolates.

AIDS-Related Opportunistic Infections↗
PubMed1993

Persistence of initial infection in recurrent Cryptococcus neoformans meningitis.

Patients with cryptococcal meningitis tend to have recurrences of infection. Although the original strain of Cryptococcus neoformans is assumed to persist in recurrent infections, this assumption has not been tested. Southern blot hybridisation with two genomic DNA probes and pulsed-field electrophoresis of intact chromosomes were used to investigate the genetic relation between initial and relapse isolates of C neoformans from patients with recurrent cryptococcal meningitis. Eleven isolates were obtained from four patients (three with AIDS, one with leukaemia). Isolates from each patient could be distinguished from those of the other patients; however, each patient's initial and recurrence isolates were clonally related. Our results provide strong evidence that clinical recurrences of cryptococcal meningitis result from persistence of the original infecting strain.

Acquired Immunodeficiency Syndrome↗
PubMed1993

False-negative cerebrospinal fluid cryptococcal latex agglutination tests for patients with culture-positive cryptococcal meningitis.

Three cases of false-negative cerebrospinal fluid latex agglutination test results for patients with culture-positive cryptococcal meningitis are reported. False-negative results occurred in settings of low cryptococcal antigen concentrations in cerebrospinal fluid and were dependent on the latex agglutination test kit used. Investigation of each case revealed that prozone phenomena or interference from bound antibody or protein could not account for the false-negative results.

Adult↗
PubMed1992

Prevention of growth of Yersinia enterocolitica in blood by polyester fiber filtration.

The ability of polyester white cell-reduction blood filters to prevent the growth of Yersinia enterocolitica in units of donated blood was studied. Sixteen units of freshly drawn blood were inoculated with 10, 50, 100, or 150 colony-forming units (CFU) per mL of a clinical isolate of Y. enterocolitica (serotype O:3). The units were subsequently fractionated into red cell concentrate and resuspended in AS-1 or AS-3 solution. One-half of the red cell concentrates in each solution were filtered within 15 hours of phlebotomy and stored for 42 days. The remaining units served as unfiltered controls. Bacterial growth was monitored by weekly cultures and, on the last storage day, by the presence of endotoxin and the formation of methemoglobin. One hundred twelve primary cultures (560 plates) were performed. Units collected in AS-1 and filtered remained sterile when initially inoculated with 50 CFU or less. Filtered units spiked with 100 CFU or less and collected in AS-3 remained sterile throughout their shelf life. All unfiltered units supported bacterial growth and the formation of endotoxin and methemoglobin. The filtration of freshly donated blood proves to limit the growth of Y. enterocolitica in red cell components.

Blood Gas Analysis↗
PubMed1992

Extensive allelic variation in Cryptococcus neoformans.

The orotidine monophosphate pyrophosphorylase (OMPPase) gene locus of the DNA of 13 Cryptococcus neoformans var. neoformans strains, including 10 recent clinical isolates, was studied by using restriction fragment length polymorphisms and nucleotide sequence analysis. The OMPPase locus (URA5) is highly polymorphic, and at least six alleles were identified. The nucleotide sequences of some alleles differed by up to 5%. The majority of the nucleotide polymorphisms in the protein-coding region occurred at the third codon position and were silent. The low frequency of replacement nucleotide substitutions relative to silent nucleotide substitutions implied that there is strong selection against amino acid changes in OMPPase. The allelic variation suggested that there is extensive genomic diversity among C. neoformans clinical isolates from one geographic area. The various alleles are potentially useful markers in the study of the population structure, epidemiology, and pathogenesis of C. neoformans strains.

Alleles↗
PubMed1982

Comparison of methods for the immunological identification of Neisseria gonorrhoeae in clinical specimens using commercially-obtained reagents.

Neither an immunofluorescent nor a co-agglutination method was adequately sensitive for the detection of Neisseria gonorrhoeae when commercially-obtained reagents were used to test oxidase positive organisms taken directly from Transgrow medium. The sensitivity of co-agglutination, the better of the two methods, was improved from 83% to 96% when organisms were subcultured for colony isolation prior to identification. False positive results were obtained with both methods.

Agglutination Tests↗
PubMed1980

Piperacillin: evaluation against inpatient and gentamicin-resistant bacteria.

When species-matched collections, each consisting of 128 bacterial strains, were compared, inpatient organisms were found to be significantly more resistant to piperacillin than outpatient organisms. A collection of 143 gentamicin-resistant gram-negative bacilli was significantly more resistant to piperacillin than a species-matched collection of gentamicin-sensitive organisms. Piperacillin resistance was transferred by conjugation from isolates of 8 different Enterobacteriaceae species to a recipient Escherichia coli strain. In each of 67 mating experiments in which transfer of carbenicillin resistance by conjugation occurred, resistance to ticarcillin, azlocillin and piperacillin was also transferred. As in previous studies, piperacillin was found to be markedly more active against non-fastidious gram-negative bacilli than carbenicillin, ticarcillin or azlocillin. Nevertheless, piperacillin resistance, apparently plasmid mediated, was detected in multiple species.

Bacteria↗
PubMed1979

Sensitivity of gentamicin-resistant Enterobacteriaceae to cefamandole and cefoxitin.

A collection of gentamicin-resistant Enterobacteriaceae strains was significantly more resistant to cefamandole than a species-matched collection of gentamicin-sensitive organisms. Cefamandole and gentamicin resistance could be simultaneously transferred by conjugation from four different species, Citrobacter freundii, Escherichia coli, Klebsiella pneumoniae and Serratia marcescens, to a recipient E. coli strain. Plasmids specifying linked resistance to cefamandole and gentamicin are thus commonly present in the environment of our medical center despite the fact that cefamandole has never been used here. Gentamicin-resistant organisms were not more resistant to cefoxitin than gentamicin-sensitive isolates. Conjugal transfer of cefoxitin resistance could not be demonstrated. Relative resistance to cefoxitin was nevertheless common among Enterobacter and Serratia isolates.

Cefamandole↗
PubMed1979

Susceptibility of streptococci to newer tetracyclines and cephalosporins and to other antimicrobial agents.

Two hundred and thirty-nine strains of Streptococcus including 71 strains of Group A, 81 strains of Group B, 69 strains of enterococci, and 18 strains of S. pneumoniae were tested against 12 antimicrobial agents using an agar dilution method. Cefamandole was the most active cephalosporin tested. Doxycycline and minocycline were more active than tetracycline, although the tetracyclines were considerably less inhibitory than the cephalosporins. Regression line analysis of zones of inhibition versus minimal inhibitory concentration values for tetracycline and minocycline showed the tetracycline disc to be unacceptable for predicting the susceptibility of the Group A Streptococcus to minocycline. Minimal inhibitory concentrations for clindamycin, erythromycin, chloramphenicol, nitrofurantoin, and spectinomycin are also given.

Cefamandole↗
PubMed1978

Laboratory evaluation of a multitest system for identification of gram-negative organisms.

Seventy-two oxidase-positive or nonfermentative organisms, or both, all of which could be identified with reasonable certainty by alternative means, were used to challenge the OXI/FERM tube. There was 91% concurrence of identification between the two methods. Three observers, working independently, agreed upon the interpretation of each of the tests in the OXI/FERM system from 91% to 100% of the time. Duplicate OXI/FERM tubes inoculated with the same strain yielded identical interpretations 95% of the time for all tests except citrate utilization (89%). The OXI/FERM tube thus appeared to be an accurate identification method and yielded test results that were easily interpreted and adequately reproducible.

Bacteria↗
PubMed1978

In vitro antibiotic sensitivity of Moraxella species.

Minimal inhibitory concentrations of 17 antibacterial agents for 34 Moraxella strains were determined using a plate dilution method. A strain of Moraxella nonliquefaciens was found which produced beta-lactamase and was resistant to ampicillin and carbenicillin but not to cephalothin. Several strains were relatively resistant to erythromycin and sulfisoxazole. Disk sensitivity tests could be used to reliably predict penicillin and erythromycin resistance but not sulfisoxazole resistance.

Anti-Bacterial Agents↗
PubMed1977

The clinical significance of Acinetobacter species.

Of 50 consecutive patients from whom Acinetobacter species were isolated, only one had an infection due to the organism which required antibiotic therapy. Fourteen of the isolates were associated with minor body surface infections and the remainder occurred as the result of either colonization without infection or culture contamination. The taxonomy, natural occurrence and antibiotic sensitivity of Acinetobacter species and their differentiation from more pathogenic organisms are reviewed.

Acinetobacter↗
PubMed1976

Room temperature incubation of dipslide urine cultures.

Two hundred and fifty urine specimens selected at random were cultured simultaneously by routine methods and on dipslides containing MacConkey agar and cystine-lactose electrolyte deficient agar with colistin (CLED-colistin agar) at room temperature incubation. There were six major and five minor differences between the two methods in interpretation of results. Many of these differences were due to the fact that CLED-colistin agar fails to support the growth of many gram-positive species, and that the dipslide tended to overestimate the colony count. Nevertheless there was sufficient agreement between the two methods to suggest that dipslides can be used effectively in office or clinic without the need for an incubator.

Bacteria↗