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S H Gillespie

Publications and source records attributed to S H Gillespie.

At least 55 records · Page 3Linked to original sources
PubMed1997

IS6110 homologs are present in multiple copies in mycobacteria other than tuberculosis-causing mycobacteria.

We have previously demonstrated homology between a 181-bp fragment of IS6110 and DNA from mycobacteria other than tuberculosis-causing mycobacteria (MOTT). Genomic DNA from 14 strains of MOTT was digested with PvuII and was hybridized with a probe derived from the 181-bp fragment and the INS1/INS2 international standard probe at high stringency. Multiple banding patterns were obtained from isolates of M. avium-M. intracellulare, M. fortuitum, M. kansasii, and M. malmoense. Differences in the banding patterns between and within species were obtained. This suggests that mycobacteria possess a family of IS3-like elements. The species of isolates suspected of being M. tuberculosis must be carefully determined before IS6110 restriction fragment length polymorphism analysis, and caution must be used in designing and evaluating diagnostic PCR tests based on this element.

DNA Transposable Elements↗
PubMed1997

An outbreak of penicillin resistant Streptococcus pneumoniae investigated by a polymerase chain reaction based genotyping method.

AIMS: To characterise the genotypes of penicillin resistant Streptococcus pneumoniae infecting patients in a care of the elderly ward and to study its transmission in a hospital environment. METHODS: Isolates of S pneumoniae were cultured from specimens obtained from patients who had been admitted to a care of the elderly ward where an outbreak had occurred. Penicillin resistant S pneumoniae were also obtained from a series of surveillance throat swabs taken from patients in the same ward. In addition, all penicillin resistant S pneumoniae isolated from specimens submitted for culture at the time of the outbreak were included. Four sensitive strains isolated from a routine microbiology laboratory were included as controls. A simple polymerase chain reaction (PCR) based genotyping method for the penicillin binding protein (PBP) genes 1a, 2x, and 2b was used to characterise the genotypes. RESULTS: Nine patients were infected with serotype 9 S pneumoniae. Four of these patients died; two deaths were directly attributable to the infection. Tested against a battery of haemolytic streptococci and other organisms found in the respiratory tract, only two false positive reactions for PBP 2x were found among S mitis. The method demonstrated that the outbreak strain had altered PBP 1a, 2b, and 2x genes, a pattern clearly distinguishable from other penicillin resistant strains isolated at the same time. CONCLUSIONS: This method is simple to perform and would enable many laboratories to characterise the genotype of penicillin resistant S pneumoniae and investigate transmission in their hospitals.

Aged↗
PubMed1996

Investigation of a choline phosphate synthesis pathway in Streptococcus pneumoniae: evidence for choline phosphate cytidylyltransferase activity.

In this study we have demonstrated the activity of a choline phosphate cytidylyltransferase in cell free extracts of Streptococcus pneumoniae. Southern blot analysis of restricted S. pneumoniae genomic DNA probed with the gene coding for the choline phosphate cytidylyltransferase of Saccharomyces cerevisiae demonstrated that there is homology between the S. cerevisiae cct gene and genomic DNA of S. pneumoniae. We believe that this enzyme is involved in the biosynthesis of the choline containing cell wall antigens, teichoic acid and lipoteichoic acid, catalysing the activation of choline phosphate to CDP-choline which is then incorporated into the polysaccharide moiety.

Animals↗
PubMed1996

Incorporation of choline into Streptococcus pneumoniae cell wall antigens: evidence for choline kinase activity.

The choline-containing teichoic and lipoteichoic acids play an important part in cell wall metabolism of Streptococcus pneumoniae. We propose that a choline kinase enzyme has a role in the synthesis of these antigens. The presence of this enzyme was demonstrated in cell free extracts of S. pneumoniae by measuring the fall in ATP concentration due to phosphorylation of choline. Genomic DNA of S. pneumoniae hybridised with a probe consisting of an internal fragment of the choline kinase gene of Saccharomyces cerevisiae and one consisting of the choline binding domain of lytA.

Antigens, Bacterial↗
PubMed1996

Evaluation of the safety and efficacy of micronized halofantrine in the treatment of semi-immune patients with acute, Plasmodium falciparum malaria.

The efficacy of the standard formulation of halofantrine hydrochloride has been compromised by the formulation's irregular bio-availability. A micronized preparation of the drug has now been evaluated in the treatment of malaria in northern Tanzania. Overall, 100 patients with mild to moderate Plasmodium falciparum malaria were recruited and treated with the preparation over 18 h. Those weighing > 40 kg were each given three, 500-mg doses and those weighing less were given roughly equivalent doses/kg. The 95 evaluable patients were all successfully treated, with a mean fever-clearance time of 22.5 h (range 4-76 h) and a mean parasite-clearance time of 35.6 h (range 15-66 h). There were no relapses. Abdominal pain was the commonest adverse event reported (22 cases). A single patient died suddenly in the recovery phase; the cause of this event was not determined. Further studies are required to evaluate the pharmacokinetics of the halofantrine formulation under field conditions.

Adolescent↗
PubMed1996

Randomized controlled trial of a drug regimen that includes ciprofloxacin for the treatment of pulmonary tuberculosis.

The fluoroquinolones are promising new antituberculous agents. A randomized controlled trial of 200 adult patients with sputum smear-positive pulmonary tuberculosis was conducted in Tanzania. Patients received either a trial regimen (HRC) consisting of isoniazid (300 mg), rifampin (600 mg), and ciprofloxacin (750 mg) or a control regimen (HRZE) consisting of isoniazid (300 mg), rifampin (600 mg), pyrazinamide (25 mg/kg), and ethambutol (15 mg/kg). The 168 evaluable patients all had negative smears and cultures by month 6, but the time to conversion to negativity was longer for the HRC group than for the HRZE group because of the poor response of patients infected with human immunodeficiency virus (HIV) to the HRC regimen. Relapse was more frequent in the HRC group. The sterilizing activity of ciprofloxacin does not appear to be equal to that of the combination of pyrazinamide and ethambutol, but the difference in outcome was significant only among HIV-infected patients.

AIDS-Related Opportunistic Infections↗
PubMed1996

Phosphorylcholine-containing antigens in bacteria from the mouth and respiratory tract.

Phosphorylcholine (PC)-containing antigens were sought in 269 bacterial isolates from the mouth and respiratory tract by an enzyme immunoassay method. Only 41 (15%) isolates were PC-positive and of these 29 (70%) were strains of Haemophilus influenzae. Other species that produced positive results included two of five isolates of Gemella haemolysans, two of five isolates of Micrococcus spp., and a single strain each of Bacillus sp., Corynebacterium jeikeium, Lactococcus sp. and H. parainfluenzae. The presence of PC-containing antigens in H. influenzae may be an important source of cross-reaction in antigen detection techniques that detect the C-polysaccharide antigen of Streptococcus pneumoniae in respiratory specimens and would result in false positive results.

Antigens, Bacterial↗
PubMed1995

Meningitis due to oral streptococci following percutaneous glycerol rhizotomy of the trigeminal ganglion.

Percutaneous rhizotomy of the trigeminal ganglion is an established technique in the management of trigeminal neuralgia. Meningitis has been reported as a complication of radiofrequency rhizotomy. We report two cases in which percutaneous glycerol injection of the trigeminal ganglion was followed by meningitis due to oral streptococci. While initial laboratory features might be considered consistent with meningitis due to Streptococcus pneumoniae, optimal therapy is likely to differ as a consequence of current antimicrobial susceptibility patterns.

Glycerol↗
PubMed1995

Demonstration of homology between IS6110 of Mycobacterium tuberculosis and DNAs of other Mycobacterium spp.?

The insertion sequence IS6110 has an important role in diagnostic PCR and typing of Mycobacterium tuberculosis. We have evaluated a one-tube nested PCR which detects IS6110. Positive results were obtained with DNAs from four of four M. tuberculosis isolates, seven of eight M. fortuitum isolates, seven of seven M. avium-M. intracellulare complex isolates, four of five M. kansasii isolates, four of five M. xenopi isolates, two of four M. malmoense isolates, and one of two M. chelonei isolates. These results were confirmed by hybridization of genomic DNA from bp 505 to 685 of the IS6110 from M. tuberculosis H37Rv. Dot blot hybridization of genomic DNAs from these isolates with the same probe cinfirmed the presence of a homologous sequence in these mycobacterial species. These data suggest that false-positive results may be obtained for clinical samples when some methods based on IS6110 are used [corrected].

Base Sequence↗
PubMed1995

Detection of C-polysaccharide in serum of patients with Streptococcus pneumoniae bacteraemia.

AIM: To investigate the fate of Streptococcus pneumoniae C-polysaccharide antigen in serum in patients with S pneumoniae bacteraemia. METHOD: In vitro dissociation experiments were performed to demonstrate that C-polysaccharide was masked by ligands in normal and acute phase serum. Serum samples from 22 patients with S pneumoniae bacteraemia were treated to dissociate immune complexes and then tested for C-polysaccharide by enzyme linked immunosorbent assay (ELISA). RESULTS: C-polysaccharide antigen was masked in normal and acute phase serum but could be released by EDTA treatment and detected by ELISA. Antigen was found in six patients ranging in concentration from 2.5 to 200 ng/ml. Patients with detectable antigen were more likely to die than those in whom antigen was not detected. CONCLUSION: This study demonstrates that C-polysaccharide antigen commonly circulates in patients with S pneumoniae bacteraemia but its presence is masked by ligands present in serum.

Acute Disease↗
PubMed1995

Anti-tuberculosis medication and the liver: dangers and recommendations in management.

In the light of three deaths due to liver failure secondary to anti-tuberculosis therapy at the Royal Free Hospital, we have reviewed the current literature, and asked--How common is liver dysfunction with anti-tuberculosis medications and how might it be prevented? Anti-tuberculosis chemotherapy is associated with abnormalities in liver function tests in 10-25% of patients. Clinical hepatitis develops in about 3%, though estimates vary, and in these patients there is likely to be significant morbidity and mortality. On the basis of reported cases of tuberculosis, 160 patients in England and Wales can be expected to develop drug-induced hepatitis due to anti-tuberculosis therapy each year. There are published guidelines from the British and American Thoracic Societies regarding the choice of drug therapy for tuberculosis. Current recommendations with regard to monitoring liver function, and what to do when these tests become abnormal, vary considerably. We suggest a protocol for using liver function tests to monitor for liver damage, and give recommendations on what action to take when these become abnormal.

Antitubercular Agents↗
PubMed1994

Polymerase chain reaction for assessing treatment response in patients with pulmonary tuberculosis.

The use of the polymerase chain reaction (PCR) for assessing treatment response in tuberculosis was investigated. Serial sputum samples were analyzed from 10 Tanzanian patients treated for smear-positive pulmonary tuberculosis, including 4 who relapsed after initially successful treatment. A one-tube nested PCR with a colorimetric detection system was compared with microscopy and culture. Samples were found to be negative by microscopy before they were by PCR or culture, often remaining positive 1-2 months longer by PCR than by culture. For the 76 samples available for both culture and PCR, there was a 76% (58/76) agreement between the methods. Nine samples were negative by culture but positive by PCR; 7 were either negative (5) or equivocal (2) by PCR despite being positive by culture. Two of the 4 relapse cases were detected earlier by PCR than by culture. These results demonstrate that PCR is a promising method for assessing treatment response in pulmonary tuberculosis.

Antitubercular Agents↗
PubMed1994

A multicentre study of the in-vitro activity of cefotaxime, cefuroxime, ceftazidime, ofloxacin and ciprofloxacin against blood and urinary pathogens.

The in-vitro susceptibilities of aerobic bacteria isolated from 1804 blood and 4529 urine specimens collected at nine hospitals in the UK were examined. An agar dilution method was used to determine the MICs of each isolate to three cephalosporins, cefotaxime, cefuroxime and ceftazidime, and to two fluoroquinolones, ofloxacin and ciprofloxacin. Sensitivities were then calculated using British Society for Antimicrobial Chemotherapy recommended breakpoints. Of the cephalosporins tested cefotaxime was the most active against the Enterobacteriaceae. All the systemic staphylococcus isolates collected were sensitive to both cefotaxime and cefuroxime. As expected, ceftazidime was the only cephalosporin active against the Pseudomonas isolates. Both quinolones were highly active against the Enterobacteriaceae and Pseudomonas spp. They also demonstrated good Gram-positive activity, particularly against Staphylococcus aureus and Enterococcus spp.

Anti-Infective Agents↗