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Biomedical subjects

J M Fox

Publications and source records attributed to J M Fox.

At least 91 records · Page 5Linked to original sources
PubMed1982

Broth microdilution testing of Pseudomonas aeruginosa and aminoglycosides: need for employing dilutions differing by small arithmetic increments.

The use of dilutions differing by small arithmetic increments was studied as a means for improving the definition and measurement of minimum inhibitory concentrations and precision parameters for testing Pseudomonas aeruginosa versus the aminoglycosides by the broth microdilution test. For five strains of P. aeruginosa versus gentamicin, tobramycin, and amikacin, comparisons were made of minimum inhibitory concentrations which were replicated in parallel by using three microdilution systems: small increment panels prepared by us, modified twofold dilution panels prepared by us, and similar modified twofold dilution panels obtained commercially. The small increment dilutions were prepared to differ by concentrations of 1.0 microgram/ml for gentamicin and tobramycin and by 2.0 micrograms/ml for amikacin. Use of the small increment dilutions resulted in the ability to measure minimum inhibitory concentrations at more closely spaced intervals than those dictated by modified twofold dilution schemes, and confidence limits were significantly improved. The average coefficient of variation for the small increment microdilution test results was 9.5%, with 99.5% of minimum inhibitory concentrations falling within +/- 2 small increment dilutions from their modal values.

Aminoglycosides↗
PubMed1982

A series of ten discoid medial menisci.

In a retrospective study, 14,731 menisci were examined to determine the incidence of discoid medial and lateral menisci. Of 8040 medial menisci, ten (0.12%) were discoid. Of 6691 lateral menisci, 102 (1.5%) were discoid. Only 22 discoid medial menisci have been reported in the medical literature. The previously reported cases were analyzed as one series and compared with the present series of ten cases as another. The incidence rate of symptoms in patients older than 18 years of age was 62% in the present series and 65% in the other series. The male to female ratio was three to one in both series. In 38% of the patients in this series trauma preceded meniscal symptoms, as compared with 66% in the literature series. Radiographic abnormalities had been reported in two of the patients reported in the literature, but none were noticed in our series. In both series, all patients recovered following meniscectomy, with the exception of one patient in our series, who developed chondromalacia patella from an unrelated patellar abnormality.

Adolescent↗
PubMed1982

Thomas B. Quigley, M.D., and the meniscus.

Utilizing material from a registry of knee surgery, subsequent operations relating to meniscectomy were reviewed. The overall reoperation rate for the entire series was 30%; 6% of the patients eventually had at least the other meniscus removed. One out of ten had subsequent anterior stabilization with or without removal of the meniscus. Only 4% had an osteotomy, knee replacement or arthrodesis at a later date. Further and expanded studies may aid in further understanding the ultimate fate of meniscectomized knees. Longer follow-up examinations are required to evaluate the long term results following removal of the meniscus through the operative arthroscope.

Arthrodesis↗
PubMed1982

Arthroscopic treatment of postoperative knee fibroarthrosis.

Twenty-four patients with severely limited knee motion following open knee surgery were treated by percutaneous release of adhesions under arthroscopic control. The mean interval between the last open surgical procedure and our treatment was 2.75 years (range, 3 months-27 years). The mean follow-up interval was eight months (range, 1 month-4 1/2 years). The mean passive flexion was increased from 70 degrees preoperation to 115 degrees at final evaluation after all arthroscopic procedures, a 45 degrees mean increase in flexion. Morbidity was low, complications were infrequent and mild, and the duration of hospitalization was brief.

Adult↗
PubMed1981

Quantitative determination of nefopam in human plasma, saliva and cerebrospinal fluid by gas-liquid chromatography using a nitrogen-selective detector.

A sensitive and selective gas-liquid chromatographic method for the determination of nefopam in human plasma, saliva and cerebrospinal fluid has been developed. The method includes the selective extraction of nefopam and the internal standard, orphenadrine, from biological fluids by a double extraction procedure. The extracted nefopam and internal standard are analyzed by a gas chromatograph equipped with a 3% OV-17 glass column and a nitrogen-phosphorus flame ionization detector (NPFID) operated in the nitrogen mode. The detector provides the needed high sensitivity and also selectivity due to the inherent characteristics of NPFID to discriminate against non-nitrogen containing materials. Five nanograms nefopam per ml plasma or saliva are routinely quantitated with a 1-ml sample or as little as 2 ng per ml cerebrospinal fluid with a 3-ml sample. The intra-day reproducibilities, expressed as the relative standard deviation, are 5, 2 and 3% at 10, 35 and 75 ng/ml plasma levels, respectively. The accuracies expressed by relative error at these levels are 12, -4 and -2%, respectively. The inter-day reproducibility is demonstrated by the small relative standard, deviation, 2%, of the slopes from ten plasma standard curves run on ten different days. In various clinical studies in humans the method has been successfully applied to the study of single-dose pharmacokinetics of nefopam and the monitoring of nefopam concentrations in saliva and cerebrospinal fluids.

Gas Chromatography-Mass Spectrometry↗
PubMed1981

Comparison of minimum inhibitory concentration values determined by three antimicrobic dilution methods for Pseudomonas aeruginosa.

This investigation compares minimum inhibitory concentration measurements by three antimicrobic dilution methods for Pseudomonas aeruginosa versus seven antimicrobics. Minimum inhibitory concentrations were measured for 650 P. aeruginosa clinical isolates and for repeated tests with P. aeruginosa ATCC 27853 versus gentamicin, tobramycin, amikacin, netilmicin, sisomicin, carbenicillin, and ticarcillin, using the macro-broth, micro-broth, and agar dilution methods. For all antimicrobics, it was found that the micro-broth and agar dilution methods produced comparable minimum inhibitory concentration measurements, which were found to lie 1 to 2 double dilution steps below those determined by the macro-broth method. Acceptably replicability was found for both the macro-broth and the agar dilution methods. The micro-broth method showed less replicability, with 4.7% of minimum inhibitory concentration values lying +/- 2 or more double dilution steps from the modal value. It is important to recognize such differences if micro-broth or agar dilution methods are substituted for the macro-broth method.

Aminoglycosides↗
PubMed1981

Inability of the API-20E system to speciate the fluorescent group of pseudomonads.

One thousand randomly selected clinical isolates of the fluorescent group of Pseudomonas were speciated in parallel by the API-20E system and by a classic microbiologic 17-test battery. The classic battery identified the isolates as 993 Pseudomonas aeruginosa, five Pseudomonas putida, and two Pseudomonas fluorescens. To augment the P. putida and P. fluorescens data, 52 reference isolates were also tested in parallel. API-20E was found to identify 99% of P. aeruginosa as P. aeruginosa. However, the 59 P. putida and P. fluorescens isolates were not accurately identified and were designated 58% P. aeruginosa, 24% P. stutzeri, 16% ambiguous categories, and only 2% in agreement with the classic designation. These findings indicated that the API-20E system does not accurately identify the non-P. aeruginosa fluorescent pseudomonads and that errors in P. aeruginosa designations will increase as the percentages of P. putida and P. fluorescens increase in the population sample.

Bacteriological Techniques↗
PubMed1981

An evaluation of burn wound quantitative microbiology. I. Quantitative eschar cultures.

The reliability of quantitative data from burn wound biopsy cultures was investigated. This was done by comparing the recovery of microorganisms from a series of burn wound eschar biopsy specimens that were each divided into two approximately equal portions and cultured in parallel. The results indicate that a microorganism present in the burn wound site in any quantity has at least a 25% chance of being missed by a single quantitative eschar culture. For recovery levels corresponding to quantitative breakpoints that have been proposed to be predictive of burn wound sepsis, only 38% of paired quantitative results agreed within the same log10 unit, and 44% differed by +/- 2 log10 units or more. These findings indicate that quantitative results derived from burn wound biopsy cultures are unreliable and may be significantly misleading when used for decision-making relative to patient care.

Bacteria↗
PubMed1981

An analysis of error rates for disc agar-diffusion testing of Pseudomonas aeruginosa versus aminoglycosides.

Five hundred thirty-five recent clinical isolates of Pseudomonas aeruginosa were tested in parallel by the standardized disc agar-diffusion test and a micro-broth dilution test to evaluate the error rates associated with the use of both fixed indeterminate-zone breakpoints and floating indeterminate-zone breakpoints for assessing susceptibility to amikacin, gentamicin, and tobramycin. Error rate-bound analysis showed that unacceptably high rates of error were associated with the use of all fixed breakpoints. Error rates were improved when the floating indeterminate-zone principle was used, but rates still remained unacceptably high. These findings indicate the disc agar-diffusion test should not be used for testing the susceptibility of P. aeruginosa to the aminoglycosides.

Amikacin↗
PubMed1981

Evaluation of the repliscan system for Enterobacteriaceae identification.

A total of 1,013 isolates of Enterobacteriaceae were identified in parallel by the Repliscan (Cathra International, Ontario, Canada) and API 20E (Analytab Products, Plainview, N.Y.) systems. There was a 62% agreement at the genus level between the two systems. Of the 38% discrepant results, Repliscan classified 22% as "biochemical pattern not on file," 8% as a multiple-genus group which included the API 20E identification, and 8% as a genus other than that designated by API 20E. Relative to the various genera, Repliscan agreed with API 20E as follows: Escherichia coli, 80%; Klebsiella spp., 76%; Citrobacter spp., 75%; Proteus spp., 69%; Providencia spp., 54%; Serratia spp., 49%; Enterobacter spp., 25%; Shigella spp., 4%; and Salmonella spp., 0%. Repliscan identified 35% of Enterobacter spp. isolates as Citrobacter spp., 91% of Shigella spp. isolates as a multiple-choice-genus group, and 67% of Salmonella spp. isolates as "biochemical pattern not on file." Repliscan agreed with API 20E at the species level as follows: E. coli, 80%; Klebsiella spp., 56%; Citrobacter spp., 66%; Proteus spp., 55%; Providencia spp., 46%; Serratia spp., 39%; Enterobacter spp., 18%; Shigella spp., 4%; and Salmonella spp., 0%. These findings indicate that the Repliscan system in its present stage of development does not reliably identify the Enterobacteriaceae.

Bacteriological Techniques↗
PubMed1981

Evaluation of the Repliscan II System for identification of Enterobacteriaceae.

In a precious report (Woolfrey et al., J Clin. Microbiol. 13:58-61, 1981), we indicated that the Repliscan system did not reliably identify Enterobacteriaceae. Recent improvements in the system prompted us to evaluate Repliscan II (Cathra International, Inc., St. Paul, Minn.) by using representative isolates of the population sample previously used to test the system. Isolates (692) representing eight genera were identified in parallel by the Repliscan II and API 20E (Analytab Products, Plainview, N.Y.) systems. Isolates given different identifications by the two systems were assigned reference identifications by using classical microbiological methods. Repliscan II identified 95.2% correctly, 4.0% incorrectly, and 0.7% as unknown. API 20E identified 99.4% correctly, 0.6% incorrectly, and none as unknown. Repliscan II correctly identified Salmonella and Shigella spp. to the genus level and isolates of six other genera to the species level as follows: Salmonella spp., 100%; Shigella spp., 97.7%; Escherichia spp., 95.2%; Citrobacter spp., 82.1%; Enterobacter spp., 85.2%; Klebsiella spp., 98.6%; Proteus spp., 97.2%; and Serratia spp., 97.9%. These findings indicate that Repliscan II is a significantly improved system and provides acceptable identification of Enterobacteriaceae.

Bacteriological Techniques↗
PubMed1980

Does the Silastic Eustachian Tube prosthesis improve eustachian tube function?

This clinical study attempts to evaluate the effectiveness of Eustachian tube function in 30 ears, 11-29 months after insertion of the Silastic Eustachian tube prosthesis (SETP). Indications for the SETP were limited to persistent Eustachian tube dysfunction. Preoperatively, 13 patients had intact tympanic membranes with persistent serous otitis media. Seventeen patients underwent tympanoplasty and demonstrated persistent serous otitis media in the opposite ear. Postoperatively, aeration of the middle ear was evaluated by tympanometry, microscopic examination, and myringostomy. Microphotographs demonstrate the state of the middle ear. Histology of the middle ear mucosa was obtained in a few cases. Ninety-six percent of the ears with an SETP demonstrated confirmed persistent Eustachinan tube dysfunction beginning an average of six months after insertion. Complications were common.

Adult↗
PubMed1980

Functional evaluation of the pes anserinus transfer by electromyography and gait analysis.

The effectiveness of the pes anserinus transfer, proposed by Slocum and Larson to control anteromedial rotatory instability of the knee, depends on the pes anserinus muscles contracting at times when the instability threatens the patient's function. To examine the activity of the transferred pes anserinus muscles, quantitated dynamic electromyography, isometric testing of muscle strength, and gait-analysis techniques were employed. Seven normal subjects and nine patients who had undergone pes anserinus transfer for anteromedial rotatory instability were tested. In contrast to the normal subjects, who demonstrated pes anserinus muscle activity primarily during swing phase, the patients displayed conspicuous activity of the semitendinosus, gracilis, and sartorius tendons during stance phase. Quantitated electromyography indicated that the pes anserinus muscles worked harder in the patients than in the normal subjects, and more effort was required from the muscles of patients with poor results than from those of patients with good results. All of the patients also demonstrated reduction of single-limb support time, as well as a shorter stride length and reduced gait velocity. We concluded that the pes anserinus transfer is kinetically sound. Since instability of the knee is a functional defect that is present during stance, the finding of marked activity of the pes anserinus muscles during stance phase in the patients but not in the normal subjects suggests that these muscles were being used to control the instability.

Adolescent↗
PubMed1979

Patellofemoral replacement.

From an analysis of the clinical evaluation of 85 cases and subsequent revisionary procedures, patients for isolated patellofemoral joint replacements should be carefully selected. At the present time, the primary indications are distortion or severe degeneration of the femoral groove.

Adult↗