Biomedical subjects
Publications and source records attributed to J A Jacobs.
The need for rapid laboratory results has marked the application of bronchoalveolar lavage (BAL) fluid cytology as a valuable tool in the assessment of infectious lung conditions. The techniques of BAL fluid processing presented here can be performed in a microbiological laboratory. The diagnostic value of BAL fluid cytology for the prediction of ventilator-associated pneumonia is discussed.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Antigenic and nucleotide sequence analyses have shown that two distinct biotypes of rabies virus are circulating in South Africa. One of these typically infects members of the family Canidae, while the other comprises a heterogeneous group of apparently indigenous viruses, infecting members of the Viverridae family. In recent times, it has become evident that a considerable amount of cross-infection may occur and the manifestation of viverrid rabies in non-viverrid animals in particular appears to have become more commonplace. Consequently, the need to rapidly distinguish between rabies virus biotypes has become increasingly important in efforts to monitor the epidemiology of rabies in the southern African region. In this study, a nested polymerase chain reaction (PCR) assay was developed to distinguish between these two groups of rabies viruses. Consensus oligonucleotides were used to amplify the cytoplasmic domain of the rabies virus glycoprotein and the adjacent intergenic region. The resultant amplicon was subsequently used as template in second round heminested PCR in the presence of type-specific primers, thereby successfully generating amplicons of characteristic size for each biotype.
Four case histories are reported in which the initial signs and symptoms were those of pulmonary infiltration and in which subsequently a diagnosis of myelodysplasia was made. The analysis of bronchoalveolar lavage fluid--demonstrating predominantly neutrophils and lymphocytes, and, occasionally blast cells as well as plasma cells--indicated that the pulmonary infiltration was related to the myelodysplastic process. As no other causes of pulmonary infiltration could be found, it seems that a pulmonary infiltrate can be the presenting symptom of a myelodysplastic syndrome. Although pleuropulmonary infiltrates most often are caused by infections, these cases illustrate that myelodysplasia related infiltrates should also be considered.
Organic solvents are widely used in industrial processes and found in many common household products. Exposures to solvents are common in both idustrialized and industrializing countries. While organic solvents exposure is well known to produce central nervous system toxicity, hepatic, renal and dermatologic injury, the respiratory effects of solvent exposure are poorly documented. Several recent population-based epidemiologic studies have found an independent association of occupational solvent exposure with respiratory symptoms, impaired pulmonary function or respiratory disease, but interpretation of these studies is limited by self-reported exposure data. Animal studies have demonstrated adverse effects in both the conducting and the respiratory airways, although often at very high exposure levels. Human chamber studies have most consistently reported irritation of the eyes, nose and throat without evidence of airway hyper-responsiveness. Case series have observed obstructive and restrictive effects in patients with high level inhalational exposures to solvents, particularly formaldehyde, but occupational epidemiologic studies have not consistently demonstrated changes in pulmonary function. Finally, mortality studied have not found increased mortality rates from respiratory disease in occupations associated with solvent use. In general, solvents have been demonstrated to cause mucosal irritation of the eyes and upper airways, but studies of pulmonary impairment following exposure have been limited and inconsistent. Solvent-mediated respiratory toxicity is biologically plausible, but further research is needed to better characterize exposures and to elucidate the specific mechanisms associated with injury.
A collection of 423 clinical "Streptococcus milleri' strains was speciated and tested for susceptibilities to twelve antibiotics. Only 1.4% of the strains were of intermediate susceptibility to penicillin. None of the strains exhibited high-level resistance to gentamicin. Strains resistant to erythromycin, roxithromycin and clindamycin were found with a frequency of 2.6%, 2.4% and 2.4% respectively. Doxycycline resistance was found in 5.7% of the strains and occurred most frequently in Streptococcus anginosus. All the strains were susceptible to cefotaxime, vancomycin and teicoplanin. The results of this study do not indicate changing antibiotic resistance in strains of the "S. milleri' group, but local differences in antibiotic susceptibilities may occur.
A collection of 399 "Streptococcus milleri" strains were identified to the species level by the use of a line blot assay. Their PCR-amplified partial 16S rRNA gene sequences were hybridized with species-specific 5'-biotinylated oligonucleotide probes homologous to the bp 213 to 231 regions of the 16S rRNA gene sequences of the type strains Streptococcus anginosus ATCC 33397, Streptococcus constellatus ATCC 27823, and Streptococcus intermedius ATCC 27335. The hybridization results were compared with the reference phenotypic identification method data (R. A. Whiley, H. Fraser, J. M. Hardie, and D. Beighton, J. Clin. Microbiol. 28:1497-1501, 1990). Most strains (357 of 399 [89.5%]) reacted unambiguously with only one probe. However, 42 of the 399 strains (10.5%) reacted with both the S. constellatus- and S. intermedius-specific probes; 41 of them were phenotypically identified as S. constellatus. These dually reactive strains hybridized with a 5'-biotinylated probe based on the bp 213 to 231 region of the 16S rRNA gene sequence of one of two species. Analysis of the 5' ends of the 16S rRNA gene sequences (487 bp) demonstrated that the dually reactive strains represent a distinct rRNA population sharing 98.1% sequence similarity with S. constellatus. Phenotypic consistency between the dually reactive strains and the S. constellatus strains was not demonstrated. Line blot hybridization proved to be a simple and inexpensive method to screen large numbers of strains for genetic relatedness, and it allowed the detection of a distinct 16S rRNA type within the "S. milleri" group.
A 30 year old man developed lipoid pneumonia after an injection of lamp oil. In addition to "foamy" alveolar macrophages, bronchoalveolar lavage (BAL) fluid analysis showed an increased number of neutrophils. Moreover, lactate dehydrogenase (LDH) and alkaline phosphatase activities were elevated. The increase seen in LDH activity both in serum and BAL fluid was accompanied by shifts in the isoenzyme pattern in similar directions for both fluids. These findings suggest a pulmonary source for the temporary serum as well as BAL fluid LDH increase. This case indicates the usefulness of bronchoalveolar lavage fluid analysis as a probe to detect pulmonary injury caused by a pneumotoxicant and, probably, to monitor recovery or deterioration.
A collection of 518 'Streptococcus milleri' strains was tested for the presence of hydrolytic enzymes, and the results were related to the clinical significance of the strains. Ribonuclease activity was equally distributed among the three species while hyaluronidase activity was linked to Streptococcus intermedius and Streptococcus constellatus. Both enzymes were not significantly associated with infection-related strains. Deoxyribonuclease and chondroitin sulfatase activity tended to be present more frequently in Streptococcus intermedius and Streptococcus constellatus and was associated with infection-related strains (p < 0.001).
Explore the source record for details and available documents.
Thirty-one isolates of Stomatococcus mucilaginosus were cultured from the blood (n = 6), throat (n = 23) and sputum (n = 2) of 18 hospitalized patients, 13 of whom were neutropaneic and five of whom were non-neutropaneic. Antibiotic susceptibility testing, performed by means of a broth microdilution method, showed that the minimal inhibitory concentrations (MICs) of ciprofloxacin were > or = 4 mg/l for the isolates collected from neutropaenic patients. All these patients received ciprofloxacin as part of their prophylactic regimen. In contrast, the MICs for four of five isolates collected from non-neutropaenic patients, none of whom were receiving ciprofloxacin, were < or = 2 mg/l. In addition, 14 of the 31 isolates were cultured from seven neutropaenic patients, admitted to the same ward over a 12-week period. To evaluate possible cross-acquisition of strains between patients, cluster analysis of all 31 isolates was performed using phenotypic characteristics, MIC values and acid production from carbohydrates (API 50 CH). Overall, 22 isolate clusters were distinguished. In five of 18 patients, two or more isolates were cultured which belonged to different clusters. In only one patient, identical isolates were cultured from blood and from the throat. All six isolates of cluster 7 were cultured within the aforementioned 12-week period from three neutropaenic patients. These data support the possibility of cross-acquisition of strains between patients although its frequency seems to be low.
Over a 4-year-period, 104 isolates belonging to the viridans streptococci were recovered from the blood and identified to the species according to Beighton and co-workers. Streptococcus oralis was the species most frequently recovered from patients in the hematology unit [29 of 39 (74%)]. Streptococcus mitis ranked second [seven of 39 (18%)]. Both species were associated with oromucositis. Isolates presently identified as S. oralis are mainly those previously identified as S. mitis or Streptococcus sanguis II. Streptococcus milleri was most frequently isolated in the patients from the general hospital population [28 of 65 (43%) isolates]: Streptococcus anginosus (n = 20), Streptococcus constellatus (n = 4), and Streptococcus intermedius (n = 4). In 14 episodes from the general hospital population, clinical significance was judged questionable. From this part of the laboratory, clinical significance could not be predicted from the number of blood cultures grown, nor from the delay of growth detection. The Rapid ID 32 Strep system agreed well with the identifications according to the scheme of Beighton et al., whereas the API 20 Strep system did not.
A collection of 518 "Streptococcus milleri" isolates recovered from clinical specimens was identified to the species level according to recently established criteria. Streptococcus anginosus was the most frequently isolated species (59.3%), followed by S constellatus (30.3%) and S intermedius (10.4%). One third (34%) of all isolates were beta-hemolytic. The majority of S anginosus isolates were nonhemolytic, carried Lancefield group F, or were nongroupable. Most of the S constellatus isolates were beta-hemolytic, as well as 16.6% of S intermedius strains. Streptococcus anginosus was recovered more often from the genital and urinary tracts and S constellatus was recovered from the thorax. Streptococcus intermedius was mostly found in the head and neck area, but was also isolated from the abdomen and the skin, bone, and soft tissue. Streptococcus intermedius and nonhemolytic isolates were recovered most often from abscess-related specimens.
Major change is always costly, but when maintaining the status quo is even more expensive, a strategic imperative for change has been created. The process of managing change is not focused on what to change, but how change decisions can be implemented successfully. Successful organizations achieve their change objectives (human and technical) on time and within budget. Unsuccessful organizations either never accomplish what they plan or do so only after consuming a great deal more time and money than they anticipated. This article introduces an abbreviated review of the ten best practices associated with change management. The reader will recognize the multitude of variables that can be relevant to any change effort and begin to assess the matrix relationship between these interdependent variables.