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Biomedical subjects

Asko Järvinen

Publications and source records attributed to Asko Järvinen.

12 recordsLinked to original sources

Clinical manifestations and outcome in Staphylococcus aureus endocarditis among injection drug users and nonaddicts: a prospective study of 74 patients.

BACKGROUND: Endocarditis is a common complication in Staphylococcus aureus bacteremia (SAB). We compared risk factors, clinical manifestations, and outcome in a large, prospective cohort of patients with S. aureus endocarditis in injection drug users (IDUs) and in nonaddicts. METHODS: Four hundred and thirty consecutive adult patients with SAB were prospectively followed up for 3 months. Definite or possible endocarditis by modified Duke criteria was found in 74 patients: 20 patients were IDUs and 54 nonaddicts. RESULTS: Endocarditis was more common in SAB among drug abusers (46%) than in nonaddicts (14%) (odds ratio [OR], 5.12; 95% confidence interval [CI], 2.65-9.91; P < 0.001). IDUs were significantly younger (27 +/- 15 vs 65 +/- 15 years, P < 0.001), had less ultimately or rapidly fatal underlying diseases (0% vs 37%, P < 0.001) or predisposing heart diseases (20% vs 50%, P = 0.03), and their SAB was more often community-acquired (95% vs 39%, P < 0.001). Right-sided endocarditis was observed in 60% of IDUs whereas 93% of nonaddicts had left-sided involvement (P < 0.001). An extracardiac deep infection was found in 85% of IDUs and in 89% of nonaddicts (P = 0.70). Arterial thromboembolic events and severe sepsis were also equally common in both groups. There was no difference in mortality between the groups at 7 days, but at 3 months it was lower among IDUs (10%) compared with nonaddicts (39%) (OR, 5.73; 95% CI, 1.20-27.25; P = 0.02). CONCLUSION: S. aureus endocarditis in IDUs was associated with as high complication rates including extracardiac deep infections, thromboembolic events, or severe sepsis as in nonaddicts. Injection drug abuse in accordance with younger age and lack of underlying diseases were associated with lower mortality, but after adjusting by age and underlying diseases injection drug abuse was not significantly associated with mortality.

Adult↗

Pharmacokinetics of estradiol valerate and medroxyprogesterone acetate in different age groups of postmenopausal women.

OBJECTIVES: To study whether ageing affects the pharmacokinetics of estradiol valerate (E2V) or medroxyprogesterone acetate (MPA) in postmenopausal women. METHODS: Forty-six postmenopausal women from two essentially similar pharmacokinetic studies were divided into three age categories: under 60 years (n = 15), between 60 and 65 years (n = 18) and over 65 years (n = 13). They all were treated for 12 days or 14 days with four galenically identical tablets containing combinations of 1 mg or 2 mg E2V and 2.5 mg or 5 mg MPA. The studies followed an open, randomised cross-over design with no washout between the periods. Serum estradiol and MPA concentrations were measured at steady state on study day 12 or 14 of each period. RESULTS: No statistically significant differences were observed in the peak concentration (Cmax), time to peak (t(max)), AUC or elimination half-life for estradiol or MPA between the different age groups. In spite of the lack of statistical significance the AUC was on an average 1.6-fold and Cmax 1.40-fold higher in the oldest group of women than in the youngest group and age was found significant as a continuous variable for AUC and Cmax for MPA but not for estradiol. CONCLUSIONS: The results suggest that there would be no significant changes in the pharmacokinetics of estradiol between women under 60 and over 65 years of age. However, a significant trend towards higher MPA concentrations and bioavailability was observed with increasing age. The results suggest that from the pharmacokinetic point of view the relationship between estradiol and MPA dose to be used in elderly could be different from that in younger postmenopausal women, while no pharmacokinetic reasons to use lower estradiol doses in the elderly were observed.

Age Factors↗

Monitoring leukocyte traffic in vivo into human delayed-type hypersensitivity reaction.

Leukocyte traffic from blood to sites of inflammation has been elaborately studied in animal models and in vitro. However, to date, little understanding has accumulated on the process in humans in vivo. A noninvasive light confocal microscopy technique has enabled us to image leukocyte rolling, arrest and transmigrated cells in vivo in human tissues. In the current study, a delayed-type hypersensitivity (DTH) reaction was elicited in the lower lip of healthy, Bacille Calmette-Guerin (BCG)-vaccinated volunteers by injection of respective purified protein derivate (PPD), mimicking the classic cutaneous Mantoux reaction. Subjects were imaged with real-time confocal microscopy at baseline and 2, 4, 24 and 48 h after the injection. The number of rolling leukocytes did not increase significantly until at 48 h. Even then, rolling cells were seen in only a minority (23%) of blood vessels. The frequency of engaged blood vessels was, nevertheless, significantly greater than at baseline. As the inflammation generated with this challenge was mild, transmigrated leukocytes could be detected in the confocal microscopy only occasionally. Histology of biopsies taken immediately after imaging at 48 h showed a T cell-dominated leukocyte population at the site of the DTH reaction. We have thus developed a method to monitor noninvasively leukocyte traffic in vivo in human subjects during the classic inflammatory model of delayed-type hypersensitivity reaction.

BCG Vaccine↗

Lactobacillus bacteremia, clinical significance, and patient outcome, with special focus on probiotic L. rhamnosus GG.

Lactobacillus bacteremia is a rare entity, and its clinical significance is poorly defined. We have reviewed the risk factors and outcome for 89 case patients with Lactobacillus bacteremia. Species characterization was done in 53% of the cases, revealing 25 L. rhamnosus strains and 22 other Lactobacillus species. In 11 cases, the strain was identical with the probiotic L. rhamnosus GG. In 82% of the cases, the patients had severe or fatal comorbidities. Predisposing factors to bacteremia were immunosuppression, prior prolonged hospitalization, and prior surgical interventions. No significant differences were observed in these predisposing factors or clinical features between patients with cases associated with the various Lactobacillus species, other than higher C-reactive protein values in patients with L. rhamnosus bacteremia. Mortality was 26% at 1 month and was 48% at 1 year. In multivariate analysis, severe underlying diseases were a significant predictor for mortality (odds ratio [OR], 15.8), whereas treatment with antimicrobials effective in vitro was associated with lower mortality (OR, 0.22). We conclude that lactobacilli in blood cultures are of clinical significance and that their susceptibility should guide decisions about antimicrobial treatment.

Anti-Bacterial Agents↗

The common cold.

Despite great advances in medicine, the common cold continues to be a great burden on society in terms of human suffering and economic losses. Of the several viruses that cause the disease, the role of rhinoviruses is most prominent. About a quarter of all colds are still without proven cause, and the recent discovery of human metapneumovirus suggests that other viruses could remain undiscovered. Research into the inflammatory mechanisms of the common cold has elucidated the complexity of the virus-host relation. Increasing evidence is also available for the central role of viruses in predisposing to complications. New antivirals for the treatment of colds are being developed, but optimum use of these agents would require rapid detection of the specific virus causing the infection. Although vaccines against many respiratory viruses could also become available, the ultimate prevention of the common cold seems to remain a distant aim.

Adult↗

Genome diversification in Staphylococcus aureus: Molecular evolution of a highly variable chromosomal region encoding the Staphylococcal exotoxin-like family of proteins.

Recent genomic studies have revealed extensive variation in natural populations of many pathogenic bacteria. However, the evolutionary processes which contribute to much of this variation remain unclear. A previous whole-genome DNA microarray study identified variation at a large chromosomal region (RD13) of Staphylococcus aureus which encodes a family of proteins with homology to staphylococcal and streptococcal superantigens, designated staphylococcal exotoxin-like (SET) proteins. In the present study, RD13 was found in all 63 S. aureus isolates of divergent clonal, geographic, and disease origins but contained a high level of variation in gene content in different strains. A central variable region which contained from 6 to 10 different set genes, depending on the strain, was identified, and DNA sequence analysis suggests that horizontal gene transfer and recombination have contributed to the diversification of RD13. Phylogenetic analysis based on the RD13 DNA sequence of 18 strains suggested that loss of various set genes has occurred independently several times, in separate lineages of pathogenic S. aureus, providing a model to explain the molecular variation of RD13 in extant strains. In spite of multiple episodes of set deletion, analysis of the ratio of silent substitutions in set genes to amino acid replacements in their products suggests that purifying selection (selective constraint) is acting to maintain SET function. Further, concurrent transcription in vitro of six of the seven set genes in strain COL was detected, indicating that the expression of set genes has been maintained in contemporary strains, and Western immunoblot analysis indicated that multiple SET proteins are expressed during the course of human infections. Overall, we have shown that the chromosomal region RD13 has diversified extensively through episodes of gene deletion and recombination. The coexpression of many set genes and the production of multiple SET proteins during human infection suggests an important role in host-pathogen interactions.

Animals↗

Rosiglitazone in the treatment of HAART-associated lipodystrophy--a randomized double-blind placebo-controlled study.

Highly active antiretroviral therapy (HAART) is associated with metabolic adverse events such as insulin resistance and lipodystrophy, that is, atrophy of subcutaneous fat and accumulation of intra-abdominal fat. Currently, there is no pharmacological treatment for lipoatrophy. Glitazones, a novel class of insulin-sensitizing anti-diabetic agents, increase subcutaneous fat in patients with type 2 diabetes. There are no controlled studies of glitazones in patients with HAART-associated lipodystrophy (HAL). In this randomized, double-blind, placebo-controlled study, 30 patients with HAL received either rosiglitazone (8 mg daily) or placebo for 24 weeks. Baseline characteristics were compared to a group of 30 age-, sex- and weight-matched HIV-negative controls. At baseline, patients with HAL had 1.8-fold (P<0.001) more intra-abdominal and 2.4-fold (P<0.05) more liver fat than HIV-negative controls, who had 1.8-fold (P<0.001) more subcutaneous fat than the patients. After 24 weeks of treatment, rosiglitazone had no effect on body weight, subcutaneous or intra-abdominal fat (magnetic resonance imaging), total body fat (bioimpedance analysis), anthropometric measurements or serum leptin concentrations (a circulating marker of adipose tissue mass). However, rosiglitazone decreased % liver fat (spectroscopy) and serum insulin concentrations, and normalized liver function tests. During the first 12 weeks of rosiglitazone treatment, serum triglycerides increased from 3.5 +/- 0.5 to 6.5 +/- 2.0 mmol/l (from 310 +/- 44 to 575 +/- 177 mg/dl) (P<0.05) and serum cholesterol from 6.0 +/- 0.4 to 7.8 +/- 0.7 mmol/l (from 232 +/- 15 to 301 +/- 27 mg/dl) (P<0.01). Contrary to data in other patient groups, rosiglitazone did not increase subcutaneous fat in patients with HAL after 24 weeks of treatment. Rosiglitazone seemed to ameliorate insulin resistance judged by the decreased serum insulin concentrations and % liver fat. Rosiglitazone unexpectedly caused significant increases in serum triglyceride and cholesterol concentrations, which must be carefully monitored if glitazones are used in these patients.

Adult↗

High rate of monoclonal gammopathy among immunocompetent subjects with primary cytomegalovirus infection.

Serum samples from immunocompetent adults with primary cytomegalovirus (CMV) or Epstein-Barr virus (EBV) infection and from solid-organ or bone marrow transplant recipients with primary CMV infection were examined for paraproteins. Several immunocompetent patients with CMV infection but none with EBV infection presented with an M component, which implies that the M component connects CMV infection to a risk of B cell malignancy.

Adolescent↗

Increased fat accumulation in the liver in HIV-infected patients with antiretroviral therapy-associated lipodystrophy.

OBJECTIVE: To determine liver fat content in patients with highly active antiretroviral therapy (HAART)-associated lipodystrophy. BACKGROUND: Lipodystrophy in several animal models is associated with fat accumulation in insulin-sensitive tissues, such as the liver. This causes hyperinsulinaemia, dyslipidaemia and other features of insulin resistance. DESIGN: A cross-sectional study. SUBJECTS AND METHODS: Three age- and weight-matched groups were compared: 25 HIV-positive men with HAART-associated lipodystrophy (HAART+LD+), nine HIV-positive men receiving HAART, but without lipodystrophy (HAART+LD-), and 35 HIV-negative healthy men (HIV-). Liver fat content was measured using proton spectroscopy. Intra-abdominal and subcutaneous fat were determined using magnetic resonance imaging. RESULTS: Liver fat content was significantly higher in the HAART+LD+ (8 +/- 10%) than the HIV- (5 +/- 7%; P < 0.05) or the HAART+LD- (3 +/- 5%; P < 0.01) group. Liver fat content correlated with serum fasting insulin in the HAART+LD+ (r = 0.47; P < 0.05) and HIV- groups (r = 0.65; < 0.001), but not with the amount of intra-abdominal fat. Within the HAART+LD+ group, serum insulin did not correlate with the amount of intra-abdominal fat. The HAART+LD+ group had a lower serum leptin concentration when compared to the two other groups. Features of insulin resistance, including hepatic fat accumulation, were not found in HAART+LD-group. CONCLUSIONS: The severity of the insulin resistance syndrome in patients with HAART-associated lipodystrophy is related to the extent of fat accumulation in the liver rather than in the intra-abdominal region. Fat accumulation in the liver may therefore play a causative role in the development of insulin resistance in these patients.

Adipose Tissue↗

Lactobacillus bacteremia during a rapid increase in probiotic use of Lactobacillus rhamnosus GG in Finland.

Lactobacilli supposedly have low pathogenicity; they are seldom detected in blood culture. Lactobacillus rhamnosus GG, which originates indigenously in the human intestine, became available for use as a probiotic in 1990 in Finland. We evaluated the possible effects of the increased probiotic use of L. rhamnosus GG on the occurrence of bacteremia due to lactobacilli. Lactobacilli were isolated in 0.02% of all blood cultures and 0.2% of all blood cultures with positive results in Helsinki University Central Hospital and in Finland as a whole, and no trends were seen that suggested an increase in Lactobacillus bacteremia. The average incidence was 0.3 cases/100,000 inhabitants/year in 1995-2000 in Finland. Identification to the species level was done for 66 cases of Lactobacillus bacteremia, and 48 isolates were confirmed to be Lactobacillus strains. Twenty-six of these strains were L. rhamnosus, and 11 isolates were identical to L. rhamnosus GG. The results indicate that increased probiotic use of L. rhamnosus GG has not led to an increase in Lactobacillus bacteremia.

Bacteremia↗

The efficacy and safety of probiotic Lactobacillus rhamnosus GG on prolonged, noninfectious diarrhea in HIV Patients on antiretroviral therapy: a randomized, placebo-controlled, crossover study.

PURPOSE: The aim of this placebo-controlled, crossover study was to evaluate the efficacy and safety of probiotic Lactobacillus rhamnosus GG (LGG) in ameliorating gastrointestinal symptoms in HIV-infected patients on antiretroviral therapy. METHOD: Infectious causes for diarrhea (bacteria, ova, parasites, and viruses including cryptosporidium, microsporidia, and cyclospora) were excluded with fecal samples before the study. HIV-infected patients with diarrhea for more than 1 month received in randomized order probiotic LGG preparation (containing viable LGG 1-5 x 1010 cfu/dose) and placebo twice a day for 2 weeks. Gastrointestinal symptoms were assessed daily and included the daily number of bowel movements, classification of stool consistency (watery, semi-watery, loose, firm, or foaming), and Visual Analog Scale (VAS) of gastrointestinal symptoms (flatulence, stomach pain, bloating disorders, general well-being). RESULTS: Seventeen HIV-infected patients completed the study. There were no significant differences between the treatment groups in the frequency or the consistency of diarrhea. In the VAS assessments of gastrointestinal symptoms, no difference between LGG and placebo could be detected. No adverse events were reported. The number of HIV RNA copies in the blood and CD4 cell counts remained stable during the study. CONCLUSION: Probiotic LGG preparation was well-tolerated in HIV infected patients. No significant differences in noninfectious diarrhea or gastrointestinal symptoms compared to placebo could be observed in this crossover study.

Adult↗