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Staphylococcus epidermidis is an important cause of catheter-associated infections, which are attributed to its ability to form a multilayered biofilm on polymeric surfaces. This ability depends, in part, on the activity of the icaADBC locus and the icaR gene, which are involved in the production of the polysaccharide intercellular adhesin (PIA) that is functionally necessary for cell-to-cell adhesion and biofilm accumulation. The present study determined: (1) the prevalence of the icaADBC operon in S. epidermidis isolates from catheter-related and other nosocomial infections; (2) the correlation between the presence of this operon, biofilm production and resistance to antibiotics; (3) the expression of ica genes and biofilm production; and (4) the genetic relatedness of the isolates. The results showed that icaRADBC was present in 45% of the isolates included in the study, and that such isolates were significantly more resistant to the main antibiotics tested than were ica-negative isolates. The presence of the entire cluster did not always correlate with biofilm production, determined under different culture conditions, but there was evidence to suggest a correlation when at least two genes (icaAD) were co-transcribed. Eight of 18 ica-positive isolates had the entire operon in the same restriction fragment after pulsed-field gel electrophoresis, but the isolates were not clonal. Estimation of genetic relatedness indicated that ica-positive S. epidermidis isolates belonged to different lineages, distributed in only one of two major clusters, with a genetic distance of c. 0.12.

The activity of linezolid, a new oxazolidinone, was tested against 862 Gram-positive cocci isolated in Italy and compared with the activities of 12 antibiotics. Overall, MIC 90 s for linezolid (2–4 mg/L) indicated an in vitro activity comparable to that of vancomycin in methicillin-resistant Staphylococcus aureus (4 mg/L), S. epidermidis (2 mg/L) and methicillin-susceptible strains. Enterococcus faecalis strains were susceptible to linezolid (MIC 90 2–4 mg/L), glycopeptides and β-lactams. In E. faecium , only glycopeptides (MIC 90 2 mg/L) and linezolid (MIC 90 2 mg/L) were active. Linezolid was the only drug active against two strains of Enterococcus showing a VanA phenotype. Owing to its antibacterial profile, linezolid represents a promising drug for the treatment of Gram-positive infections.

A demographic simulation model is used to examine the effects of impending demographic changes particularly demographic aging in Japan the Federal Republic of Germany Sweden and the United States. "The simulation results indicate that these changes will have a major impact on rates of national saving real wage rate and current accounts. One of this papers fundamental lessons is that allowing for general equilibrium adjustments reduces the adverse welfare effects of increasing dependency ratios. Nevertheless the welfare costs and particularly their distributions across cohorts pose serious challenges for policy makers in some cases." (EXCERPT)

In recent years there has been a gradual increase in the number of infections caused by Klebsiella, Enterobacter and Serratia and non-fermentative bacilli such as Pseudomonas, Alcaligenes and Acinetobacter. The object of this investigation was to evaluate the antibacterial properties of the cephalosporins cefoxitin, cefoperazone, cefotaxime and of gentamicin, in comparison with cefotetan, a new cephamycin with a high degree of stability to beta-lactamases. The cefotetan MIC was not affected either by size of the bacterial inoculum, or the culture medium and the serum protein binding of cefotetan was 85%. Cefotetan showed only moderate antibacterial activity, similar to that of the other cephalosporins tested, against the Gram-positive cocci, whereas it was very active against fermentative and non-fermentative Gram-negative bacilli, except for Pseudomonas aeruginosa. The remarkable activity of cefotetan against Klebsiella, Enterobacter and Serratia is of particular interest.

This paper examines the empirical basis for the debt-neutrality hypothesis in an international cross-section of eight major OECD countries over the period 1961-85. The analysis uses a dynamic demand system for durable and non-durable goods derived from individual optimizing behaviour. The model nests three specifications corresponding to different degrees of consumer rationality: the traditional life-cycle consumption model, the case of inflation-adjustment of disposable income (no money illusion) and the case of full "tax discounting" (no fiscal illusion). In addition, the model incorporates explicitly the role of a variable interest rate and substitution between public and private consumption. The model is estimated using three different consumption aggregates at the single-country level and over the pooled data set. Estimates of the inflation-adjustment and fiscal illusion parameters are provided and specification tests opposing the three versions of the model are performed. The ...

Recent swings in fertility rates, combined with anticipated increases in life expectancy, are expected to result in a significant increase in the number and proportion of elderly persons in the first half of the next century. This "ageing" of OECD populations is expected to have widespread impacts, affecting labour markets, the composition and level of consumption and output, national rates of saving and the rate of capital accumulation, etc. A widely recognized effect of ageing will be the pressures it will place on public sector finances as the share of future output transferred to a large dependent population rises. This paper discusses some of the potential economic impacts of ageing. It also presents an analysis of its impacts on public pension financing requirements, with particular emphasis on selected OECD countries -- Germany, Japan, Sweden and the United States. It is shown that, where desirable, future increases in retirement age and benefit reductions could help reduce ...

Demographic changes, such as those anticipated in most OECD countries, have many economic effects that impinge on a country's fiscal viability. Evaluation of the effects of associated changes in capital-labour ratios and the welfare and behaviour of different generations requires the use of a dynamic general equilibrium model. This paper uses an overlapping generations demographic simulation model, which incorporates bequest behaviour, technological change, the possibility that the economy is open to international trade, and government consumption expenditures that depend on the age composition of the population. The model has been further adapted to study the effects of anticipated demographic changes in Japan, the Federal Republic of Germany, Sweden and the United States. The simulation results indicate that these changes could have a major impact on rates of national saving, real wage rate and current accounts. One of this paper's fundamental lessons is that allowing for general ...

Demographic changes, such as those anticipated in most OECD countries, have many economics effects that impinge on a country's fiscal viability. Evaluation of the effects of associated changes in capital-labor ratios and the welfare and behavior of different generations requires the use of a dynamic general equilibrium model. The 75 generations - 250 year demographic simulation model, presented in Auerbach and Kotlikoff (1987, Chapter 11), has been modified to incorporate bequest behavior, technological change, the possibility that the economy is open to international trade, and government consumption expenditures that depend on the age composition of the population. The model has been further adapted to study the effects of impending demographic changes in Japan, the Federal Republic of Germany, Sweden and the United States. The simulation results indicate that these changes will have a major impact on rates of national saving, real wage rate and current accounts. One of this paper's fundamental lessons is that allowing for general equilibrium adjustments reduces the adverse welfare effects of increasing dependency ratios. Nevertheless, the welfare costs, and particularly their distributions across cohorts, pose serious challenges for policy makers in some cases.

In the present study we tested the susceptibility to cefodizime on 1,985 selected nosocomial pathogens isolated in five laboratories. Moreover, we evaluated the epidemiology of the resistance of the tested strains to cefodizime and to other antibiotics clinically available in Italy. The susceptibility to cefodizime was determined with both MIC (microdilution method) and the agar diffusion method (Kirby-Bauer). The Kirby-Bauer method was used to compare the antibiotics. Cefodizime was equivalent in activity to ceftazidime and ceftriaxone and was more active than piperacillin and amoxicillin + clavulanic acid. The activity of gentamicin (where tested) was generally comparable to that of cefodizime; ciprofloxacin had lower percentages of resistance against some species of Enterobacteriaceae and staphylococci.

This is a report of our nontraumatic technique using a tubal cytobrush for epithelial tubal cell recovery during laparoscopy diagnosis of C. trachomatis salpingitis. We performed a three-way laparoscopy in 95 women and inserted a long flexible fallopian tube brush through one of the trocars. This technique showed that it is possible to reach the infection site avoiding vaginal contamination and that sufficient tubal cells can be obtained for isolation of intracellular pathogens. The technique also allowed rapid antigen detection directly on tubal cells by IFA and C. trachomatis isolation on cell culture. Tubal scraping did not cause bleeding or adhesions as later observed in a matched group of women who underwent further laparoscopy during GIFT.

Oxidative stress has been implicated as a major contributor to selective neuronal death in Parkinson's disease (PD). Vitamin E is an antioxidant that may protect the brain from free radical-induced oxidative damage. It is, therefore, reasonable to hypothesize that low levels of vitamin E concentrations may increase the risk of developing PD. To elucidate the possible role of vitamin E in the pathogenesis of PD, we assessed the plasma levels of vitamin E, measured by high-performance liquid chromatography (HPLC), in 54 patients with PD. Vitamin E concentrations were also assessed in 93 age and sex matched normal individuals. The mean plasma levels of vitamin E did not differ significantly between these two groups (22.5±8.15 μmol/l for PD patients and 21.0±7.9 μmol/l for controls). The results of our study suggest that plasma vitamin E concentrations do not play a major role in the pathogenesis of PD.

Objective: To investigate whether polymorphisms in the genes for dopamine receptors D 1 and D 2 are associated with the risk of developing peak-dose dyskinesias in PD. Background: Peak-dose dyskinesias are the most common side effects of levodopa therapy for PD. The identified predictors may only partially account for the risk of developing peak-dose dyskinesias because a substantial proportion of patients never develop peak-dose dyskinesias. Genetic factors could play a role in determining the occurrence of peak-dose dyskinesias. Methods: A case-control study of 136 subjects with sporadic PD and 224 population control subjects. We studied three polymorphisms involving the dopamine receptor D 1 gene and one intronic short tandem repeat polymorphism of the dopamine receptor D 2 gene. Results: The polymorphisms of the dopamine receptor D 1 gene were not associated with the risk of developing PD or peak-dose dyskinesias. The 15 allele of the polymorphism of the dopamine receptor D 2 gene was more frequent in parkinsonian subjects than in control subjects. More important, the frequency of both the 13 allele and the 14 allele of the dopamine receptor D 2 gene polymorphism was higher in nondyskinetic than in the dyskinetic PD subjects. The risk reduction of developing peak-dose dyskinesias for PD subjects carrying at least 1 of the 13 or 14 alleles was 72% with respect to the PD subjects who did not carry these alleles. Conclusions: Certain alleles of the short tandem repeat polymorphism of the dopamine receptor D 2 gene reduce the risk of developing peak-dose dyskinesias and could contribute to varying susceptibility to develop peak-dose dyskinesias during levodopa therapy.

The authors evaluated the in-vitro antibacterial activity of piperacillin alone and of piperacillin combined with tazobactam, a new beta-lactamase inhibitor, on 398 clinical isolates, both Gram-positive and Gram-negative. The piperacillin/tazobactam combination was evaluated in the fixed ratio 8:1. The vast majority of the microorganisms tested had reduced susceptibility to piperacillin (minimum inhibitory concentration (MIC) range 0.12- greater than 256 mg/l) due to beta-lactamase production. The following results were obtained: against Haemophilus influenzae, tazobactam was effective in reducing the MICs of piperacillin by 512 fold. The activity of piperacillin/tazobactam was lower against Pseudomonas sp., while some activity was demonstrated against some strains of Klebsiella. Good activity was seen not only against methicillin-susceptible (MS) staphylococci but also against some methicillin-resistant (MR) strains. In the latter, the combination of piperacillin/tazobactam was active only if the strains showed beta-lactamase production. These findings are interesting above all in regard to the synergistic effect demonstrated against MR beta-lactamase producing staphylococci and the Klebsiella-Enterobacter-Serratia (KES) group.

The study was carried out to clarify the correlation between Chlamydia pneumoniae infection and peripheral arterial disease (PAD). The level of specific antibodies of the 133 consecutive patients suffering from PAD at 2nd stage of Leriche's classification were compared with 60 healthy controls by using a commercial Micro-IF Test.A higher incidence of serological evidence of C. pneumoniae infection was found in the patients (106/133) than in controls (6/60).These results are in agreement with other findings that measured the infection in atheromasic plaques. A strong cause-effect relationship between bacterial infection and peripheral arterial disease was not found, but the raised seropositivity level could be considered as a target for medical therapy of PAD.

The in vitro activity of flurithromycin, a 14-membered macrolide drug, was found to be similar to that of erythromycin against 41 strains of Mycoplasma spp. and 100 strains of Ureaplasma urealyticum. All 28 strains of Mycoplasma hominis were uniformly resistant to both macrolides with MICs > 256 mg/L, U. urealyticum showed intermediate resistance with MIC50s of 0.5 and 1 mg/L for erythromycin and flurithromycin, respectively, whereas the ten strains of Mycoplasma pneumonia were susceptible to < or = 0.03 mg/L of both macrolides.

The time-kill method was used to determine the bactericidal activity of cefditoren compared with oral cephalosporins, amoxicillin, amoxicillin/clavulanate and levofloxacin against a randomly selected group of strains isolated from community-acquired respiratory tract infections (CARTIs). Cefditoren was the only agent showing significant bactericidal activity (≥3 log10 reduction of viable cells) within 4 h against all Streptococcus pneumoniae strains, both penicillin-susceptible (PEN S) or -resistant (PEN R), as well as against Streptococcus pyogenes, and Moraxella catarrhalis. Against? β-lactamase positive strains of Haemophilus influenzae, cefditoren was comparable to the quinolone and more active than other cephalosporins at 24 h. Cefditoren showed the best killing kinetic profiles and this observation may be important when choosing an oral third-generation cephalosporin as initial or sequential therapy.

Most members of the Enterobacteriaceae and Pseudomonas aeruginosa possess an inducible chromosomal class I beta-lactamase. Bacterial strains which produce high levels of beta-lactamase constitutively can be isolated from infections; these derepressed mutants are responsible for resistance to third-generation cephalosporins and ureidopenicillins. Minimum inhibitory concentrations of cefpirome, a fourth-generation cephalosporin, and other beta-lactam antibiotics were determined for a series of mutants of Citrobacter freundii, Enterobacter cloacae, Morganella morganii, Proteus vulgaris and Serratia marcescens with inducible stably derepressed or basal expression of chromosomal class I beta-lactamases. All the antibiotics tested were almost equally active against beta-lactamase-inducible organisms and their basal mutants. Imipenem and cefpirome showed better activity against derepressed mutants than third-generation cephalosporins and ureidopenicillins.

The proper and coordinated response of the host immune system to bacterial infections is known to play a central role in the eradication of an infection. Therefore, the impact of antibiotics on both innate and acquired host immunity may be involved in the therapeutic outcome. The aim of this study was to evaluate the effects of the widely used cephalosporin cefaclor on some parameters of the immune system in ex vivo conditions. The results demonstrated that short-term (3 to 6 days) treatment with this antibiotic induced pleiotropic modification of rat spleen cells upon ex vivo stimulation with the polyclonal mitogen PHA, entailing increased lymphoproliferative responses, augmented IFN-gamma, IL-2 and IL-10 synthesis and decreased production of IL-4 and IL-6 in comparison to spleen cells from control rats. The mononuclear spleen cells of healthy rats released larger amounts of IFN-gamma and IL-2 in culture supernatants in response to polyclonal mitogenic stimulation with PHA compared to the spleens of the control rats receiving vehicle only. Simultaneously, the treatment with cefaclor augmented PHA-induced lymphoproliferative responses and reduced the synthesis of IL-4 and IL-6. These data depict a type 1 cytokine inducing and immunostimulatory pharmacological profile that, by activating the innate and acquired immune system, would be synergistic with cefaclor antibacterial activity.

SummaryOne hundred eighty-four sputum specimens from the same number of patients with lower respiratory tract infections were examined to determine the bacterial count and the relationship between the microorganisms isolated and the presumptive pathology. The sputa were subdivided into three groups; “high probability”, “low probability”, and “contaminated sputa”, following the criteria of the microscopic readings: sputum with more than 25 white cells and low numbers of squamous epithelial cells represents true lower respiratory tract infections (high probability); those with fewer than 25 white cells represent non-bacterial infections or non-infected sputa (low probability) while sputa with more than 25 squamous cells per field represent contaminated specimens (contaminated sputa).Statistical analysis was carried out to correlate these data. Haemophilus influenzae, Haemophilus parainfluenzae, Streptococcus pneumoniae, and Streptococcus pyogenes showed significant differences in the three groups considered.

This study presents the results of the italian "Severe infections project" involving bacteria that can be considered rare causes of disease. we isolated 30 uncommon human pathogens from a total of 60 strains (1.2% of all the isolates). The most frequent sources of uncommon human pathogens were primary bloodstream infections (48.3%) and pneumonia (20%). Species such as Comamonas testosteroni, Enterococcus hirae, Kluyvera ascorbata, Kluyvera cryocrescens, Leclercia adecarboxylata and Ochrobactrum anthropi were recovered from bacteremia patients. Clinically useful antimicrobial agents were tested against each isolate. Resistance to 4 or more antibiotics tested was found in Achromobacter xylosoxidans, O. anthropi, Pseudomonas stutzeri, Citrobacter braakii, Enterobacter sakazakii, K. ascorbata, Proteus penneri and Serratia plymuthica. About 16% of the Gram-negative species were resistant to third-generation cephalosporins and 28.6% of the staphylococci were oxacillin-resistant. the results from this study offer indications for empirical therapy for severe infections from uncommon human pathogens.

Introduction We describe the case of a 79-year-old Caucasian Italian woman with a transient basilar occlusion monitored by transcranial Doppler, with subsequent recanalization and clinical shrinking deficit. This is the first case of transient basilar occlusive disease diagnosed and monitored by transcranial Doppler. This case is important and needs to be reported because transient basilar occlusion may be easily diagnosed if transcranial Doppler is performed. Case presentation A 79-year-old woman affected by chronic atrial fibrillation and not treated with oral anticoagulants, cardioverted to sinus rhythm during a gastric endoscopy. She then showed a sudden-onset loss of consciousness, horizontal and vertical gaze palsy, tetraparesis and bilateral miosis and coma. Two hours later, the symptoms resolved quickly, leaving no residual neurologic deficits. Transcranial Doppler examination showed a dampened flow in the basilar artery in the emergency examination and a restored flow when the symptoms resolved. Conclusion This is the first case of transient basilar occlusive disease diagnosed and monitored by transcranial Doppler. We believe that transcranial Doppler should be performed in all cases of unexplained acute loss of consciousness, in particular, if associated with signs of brainstem dysfunctions.

tetracycline (96.4%) and gentamicin (99.3%). Staphylococci included MRSA (35.7%) and MR-CoNS (68.4%); and MRSA isolates were resistant to levofloxacin (96%) and erythromycin (74%). All clindamycin-susceptible SA had inducible resistance. Dalbavancin (MIC90; 0.047mg/L) was 10-fold more potent than vancomycin (MIC90; 0.5mg/L) against BHS. Erythromycin susceptibility was 82% with a 25% inducible clindamycin resistance. Conclusions: The DECIDE study demonstrated in UK and Ireland that dalbavancin has excellent activity and was more potent when directly compared to vancomycin. Dalbavancin was active against all MRSA, although the current susceptibility profiles for other antimicrobial classes tested were of great concern, particularly inducible clindamycin resistance (100%). Monitoring dalbavancin activity should be continued as this newer long-acting agent is introduced into EU clinical practice.