Antimicrobial susceptibility to levofloxacin and other antibacterial agents among common respiratory pathogens-a Brazilian perspective from the GLOBAL Surveillance Initiative 2001-2002.

The GLOBAL (Global Landscape On Bactericidal Activity of Levofloxacin) Surveillance programme monitored antimicrobial susceptibility patterns of the key respiratory tract pathogens Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis collected in Brazil during 1997-1998, 1999-2000 and 2001-2002. Penicillin and azithromycin resistance among S. pneumoniae strains increased from 1997-1998, reaching 7.9% and 9.5%, respectively, in 2001-2002. Although decreasing by 4.9% since the previous study, trimethoprim-sulphamethoxazole resistance remained high at 33.7%. Concurrent resistance to penicillin, azithromycin and trimethoprim-sulphamethoxazole was seen in 2.9% of the S. pneumoniae isolates collected. Levofloxacin remained extremely active against S. pneumoniae, with 0.3% resistance reported in 1997-1998 and 0% resistance in 1999-2000 and 2001-2002. beta-Lactamase production in H. influenzae was > 10% in all three studies, with correspondingly high rates of ampicillin resistance. Trimethoprim-sulphamethoxazole was the least active agent tested against H. influenzae, with resistance rates of > 40% recorded in all three studies. All H. influenzae isolates were susceptible to cefuroxime, ceftriaxone, azithromycin and levofloxacin. Of the M. catarrhalis isolates, 98.0% in 1997-1998, 98.0% in 1999-2000 and 81.8% in 2001-2002 were beta-lactamase-positive. The continued high prevalence of antimicrobial resistance in Brazil underscores the importance of current surveillance initiatives. Levofloxacin, a fluoroquinolone prescribed widely for respiratory tract infections, continued to show potent activity against key respiratory pathogens.

In vitro susceptibility of Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis: a European multicenter study during 2000-2001.

OBJECTIVE: To assess the current (2001) activity of respiratory fluoroquinolones and comparator agents against respiratory pathogens isolated in European countries. METHODS: During 2000-2001, we prospectively collected 1995 isolates of Haemophilus influenzae, 1870 isolates of Streptococcus pneumoniae and 649 isolates of Moraxella catarrhalis from hospital laboratories in France, Germany, Greece, Italy, Spain and the UK. National Committee for Clinical Laboratory Standards (NCCLS)-approved broth microdilution antimicrobial susceptibility testing methods and interpretive criteria were used throughout. RESULTS: Of the S. pneumoniae isolates, 99.6% were susceptible to moxifloxacin, gatifloxacin and levofloxacin; the corresponding figure for H. influenzae was 100%. All M. catarrhalis isolates had moxifloxacin MICs

Multiple N-acyl homoserine lactone signals of Rhizobium leguminosarum are synthesized in a distinct temporal pattern.

A common form of bacterial quorum sensing involves the production and release of acyl homoserine lactone (AHL) signal metabolites. The nitrogen-fixing symbiont Rhizobium leguminosarum reportedly produces at least six different AHLs, but little is known about the regulation of biosynthesis of these molecules. We used a radiolabeling protocol to quantify the relative amounts of AHLs synthesized over time by R. leguminosarum cells with and without the symbiosis plasmid pRL1JI. Cells containing pRL1JI were found to produce three predominant signals. In decreasing order of abundance, these were N-(3-oxo)octanoyl homoserine lactone [(3-O)C(8)HSL], N-octanoyl homoserine lactone, and N-hexanoyl homoserine lactone. Cells without pRL1JI produced only two major signals, N-(3-hydroxy-7-cis)tetradecanoyl homoserine lactone [(3-OH)C(14:1)HSL] and (3-O)C(8)HSL. Each AHL exhibited a distinct temporal pattern of synthesis, suggesting that each AHL is subject to unique regulatory mechanisms. While (3-O)C(8)HSL was produced in both cultures, the patterns of synthesis were different in cells with and without pRL1JI, possibly as a result of redundant gene functions that are present on both the chromosome and the symbiosis plasmid. None of the AHLs appeared to regulate its own biosynthesis, although exogenous (3-OH)C(14:1)HSL did activate synthesis of the three AHLs made by cells containing pRL1JI. These results indicate that the synthesis of multiple AHLs in R. leguminosarum is regulated by complex mechanisms that operate independently of quorum sensing itself but that (3-OH)C(14:1)HSL can supersede these controls in pRL1JI-containing cells. This work provides an important global perspective for AHL regulation that both complements and contrasts with the results of previous studies performed with isolated gene systems.

Anti-hypertensive therapy in the elderly and its effects on cerebral function.

Seventeen patients ranging in age from 67 to 86 years were entered into a double-blind, crossover study of Moducren and placebo. Psychometric testing using the Clifton Assessment Procedure for the Elderly was performed at the start of the study and at the end of each 4-week test period. The total length of the study was 18 weeks. Apart from effectively reducing blood pressure in elderly hypertensives without causing a high incidence of side effects, plasma potassium, blood urea and cerebral function were all unaffected by Moducren.

Related age changes in the elastase and lipid contents of normal and hemiplegic subjects of various ages.

Elastase and lipid levels of the plasmas of subjects and of those who have suffered a stroke have been measured, and it has been shown that the normal age related fall in elastase content is mirrored more closely by the fall in high density lipoprotein cholesterol than by changes in total cholesterol. After a stroke a peak level of the elastase concentration is reached later than the peak of the total cholesterol, but before the peak for the HDL-cholesterol is attained. Highest levels of the ratio of these two (a major risk factor in vascular disease) appear to precede both the stroke and the elevation of the elastase level at ages below 76 whereas at higher ages than this the elevation of elastase precedes the lipid changes. It is therefore deduced that the whole question of elastolytic activity in the plasma is intimately bound up with the lipid content of the plasma and with the age of the subject as mirrored in the status of the elastic tissue in the vessel wall.

Serum elastase levels following a stroke in elderly subjects.

The elastase content of the serum of stroke patients is appreciably higher immediately after the cerebral incident and, in the case of those destined to survive, falls subsequently back to the normal level for their age group. The degree of elevation of the elastase content, the period which elapses before it is attained and the rate at which the level returns to normal are all age related. Those patients who die within 1 week of their initial stroke suffer a dramatic rise in serum elastase content immediately prior to death.

Magnapen treatment of infections in the elderly.

Magnapen is a combination of two well-proven semi-snythetic penicillins which together offer the theoretical advantages of a broad spectrum of activity, good bioavailability and a low incidence of side-effects. It is of particular value in treating infections in the elderly. In this study the theory is borne out in practice in a population presenting special problems for which this combination seems particularly appropriate. Ninety-six patients have been treated with a course of Magnapen syrup. Of the total entered into the study, 73% of patients were clinically cured following therapy, with a further 19% improved. Clinical failure occurred in 8% of patients. Fifty-two patients were bacteriologically assessable, forty-seven of whom (90%) had infecting organisms cleared by therapy. Side-effects occurred in four patients (4%), one of whom had to discontinue therapy.

Temazepam (Euhypnos) and chlormethiazole: a comparative study in geriatric patients.

The sleep-inducing properties and tolerance of temazepam formulated in solution in soft gelatine capsules were compared with chlormethiazole syrup in two groups of geriatric in-patients. Both compounds appeared to be safe, effective and well-tolerated, but significant differences in favour of temazepam were observed in quality and duration of sleep, ease of awakening and carry-over effects. This formulation of temazepam (Euhypnos) would appear to be an ideal sleep-inducer for geriatric patients.

A nutritional survey in the elderly: blood and urine vitamin levels.

In this survey of vitamin levels in 93 acute geriatric admissions to hospital, none had a completely normal nutritional profile. Twenty-two patients had over 50% of test abnormal and for all patients the average % of abnormal tests was 29%. The most common abnormalities were albumin, leucocyte vitamin C, vitamin E, carotene and nicotinic acid where over 50% of patients had abnormal results. Transferrin and vitamin A levels were abnormal in over 30% of patients while there was little evidence for riboflavin or thiamine malnutrition. It is postulated that an inadequate dietary intake, due to disease or to physical and mental deterioration was the most likely cause of these multiple nutritional abnormalities.