Showing papers by "Swedish Institute published in 2001"
TL;DR: The weaker H. pylori-cancer relationships in studies based on IgG ELISA rather than CagA may be caused by misclassification of relevant exposure, and a much stronger relationship emerges with more accurate exposure classification.
442 citations
TL;DR: Measurements of the mutation frequency to rifampicin resistance in Helicobacter pylori strains isolated from dyspeptic patients showed that ≈1/4 of the isolates had higher mutation frequencies than Enterobacteriaceae mismatch-repair defective mutants, indicating that compensation is a clinically relevant phenomenon that could act to stabilize resistant bacteria in a population.
Abstract: Among the several factors that affect the appearance and spread of acquired antibiotic resistance, the mutation frequency and the biological cost of resistance are of special importance. Measurements of the mutation frequency to rifampicin resistance in Helicobacter pylori strains isolated from dyspeptic patients showed that approximately 1/4 of the isolates had higher mutation frequencies than Enterobacteriaceae mismatch-repair defective mutants. This high mutation frequency could explain why resistance is so frequently acquired during antibiotic treatment of H. pylori infections. Inactivation of the mutS gene had no substantial effect on the mutation frequency, suggesting that MutS-dependent mismatch repair is absent in this bacterium. Furthermore, clarithromycin resistance conferred a biological cost, as measured by a decreased competitive ability of the resistant mutants in mice. In clinical isolates this cost could be reduced, indicating that compensation is a clinically relevant phenomenon that could act to stabilize resistant bacteria in a population.
390 citations
TL;DR: An intensified prevention strategy including patient education, foot care and footwear is cost-effective if the risk for foot ulcers and lower extremity amputations can be reduced by 25 %.
Abstract: We analysed the cost-effectiveness of intensified prevention in diabetic patients with different risks for foot ulcers and lower extremity amputations. Specifically, we examined whether the additional prevention costs associated with present recommendations would be offset by reduced costs of future foot ulcers and amputations. Markov-based 5-year cost-utility simulations of current versus optimal prevention were done for hypothetical cohorts of diabetic patients older than 24 years. The model included eight possible health states for four risk groups. A population of 1677 diabetes patients provided data on present foot ulcer prevention and general mortality. Optimal prevention was defined according to the International Consensus on the Diabetic Foot. Model assumptions, transition probabilities and other data included in the model were based on published literature. The main outcome measures were cumulative incidences of foot ulcers, amputations and deaths, costs, cost-effectiveness, and quality-adjusted life years. An intensified prevention strategy including patient education, foot care and footwear is cost-effective if the risk for foot ulcers and lower extremity amputations can be reduced by 25 %. This is valid for all patients with diabetes except those with no specific risk factors. Providing all diabetic patients at risk or high risk for foot ulcers and amputations with adequate prevention would be a cost-effective or even cost-saving strategy. [Diabetologia (2001) 44: 2077–2087]
209 citations
TL;DR: The host interactions of the viruses, including the rodent reservoirs, the clinical outcome of human infections as well as the pathogenesis and laboratory diagnosis of infections are covered.
206 citations
TL;DR: Restriction fragment length polymorphism (RFLP) analysis of 209Mycobacterium tuberculosis clinical isolates obtained from newly detected pulmonary tuberculosis patients in Estonia during 1994 showed that 61 isolates belonged to a genetically closely related group of isolates, family A, with a predominant IS6110 banding pattern.
Abstract: Restriction fragment length polymorphism (RFLP) analysis of 209 Mycobacterium tuberculosis clinical isolates obtained from newly detected pulmonary tuberculosis patients (151 male and 58 female; mean age, 41 years) in Estonia during 1994 showed that 61 isolates (29%) belonged to a genetically closely related group of isolates, family A, with a predominant IS6110 banding pattern. These strains shared the majority of their IS6110 DNA-containing restriction fragments, representing a predominant banding pattern (similarity, >65%). This family A comprised 12 clusters of identical isolates, and the largest cluster comprised 10 strains. The majority (87.5%) of all multidrug-resistant (MDR) isolates, 67.2% of all isolates with any drug resistance, but only 12% of the fully susceptible isolates of M. tuberculosis belonged to family A. These strains were confirmed by spoligotyping as members of the Beijing genotype family. The spread of Beijing genotype MDR M. tuberculosis strains was also frequently seen in 1997 to 1999. The members of this homogenous group of drug-resistant M. tuberculosis strains have contributed substantially to the continual emergence of drug-resistant tuberculosis all over Estonia.
189 citations
TL;DR: The influence of processing conditions during melt extrusion on the degradation of poly(L-lactide) (PLLA) has been investigated in this article, where a double screw extruder at 210 and 240°C was used.
Abstract: The influence of processing conditions during melt extrusion on the degradation of poly(L-lactide) (PLLA) has been investigated. PLLA polymer was processed by melt extrusion in a double screw extruder at 210 and 240°C. For each extrusion temperature, two screw rotation speeds, 20 and 120 rpm, were used. To investigate the influence of moisture on the thermal degradation during processing, the PLLA granules were dried at 100°C for 5 h and then either extruded directly or conditioned at 65% RH, 20°C for 24 h prior to extrusion. The results show that a decrease in molecular weight measured as number-average (Mn) molecular weight occurs for all combinations of process parameters used. At processing temperature of 210°C, the change in molecular weight for the dry granules was shown to be dependent on the residence time (i.e., screw rotation speed) in the melt. By changing the screw rotation speed from 120 to 20 rpm at 210°C, Mn decreased from 33,600 to 30,200 g/mol. When the processing temperature was increased to 240°C, the dry granules showed an Mn of 25,600 and 13,600 g/mol when extruded at 120 and 20 rpm, respectively. Mn for the conditioned specimens extruded at 210°C was 18,400 g/mol when processed at 120 rpm and 12,300 g/mol at 20 rpm. When processed at 240°C, 20 rpm, Mn is independent of whether the granules were dry or moist prior to extrusion. It is probably due to the fact that the degradation at 240°C is so extensive that the presence of moisture in the polymer does not contribute further to the degradation process. The stress and strain at break decreased due to degradation and were dependent on the molecular weight of the samples. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 79: 2128–2135, 2001
168 citations
TL;DR: Lowering aw seems to protect both E. coli and S. cerevisiae from PEF processing, and a synergy of low pH values, high temperatures andPEF processing was observed.
Abstract: The aim of this study was to examine the influence of pH, water activity (aw) and temperature on the killing effect of pulsed electric fields (PEF). Escherichia coli and Saccharomyces cerevisiae suspended in a model media were subjected to 20 pulses with 4 μs duration in a continuous PEF system, during which the effects of pH (4.0–7.0), aw (1.00–0.94) and inlet temperature (10°C and 30°C) could easily be studied. Electrical field strengths were set to 25 kV/cm for S. cerevisiae and 30 kV/cm for E. coli and the highest outlet temperature was monitored to 44°C. A synergy of low pH values, high temperatures and PEF processing was observed. A drop in pH value from 7.0 to 4.0 resulted in the reduction of E. coli by four additional log units, whereas for S. cerevisiae, the pH effect was less pronounced. Lowering aw seems to protect both E. coli and S. cerevisiae from PEF processing.
161 citations
TL;DR: Observations suggest that PEF treatments have profound direct or indirect effects on the intracellular organisation of microorganisms.
Abstract: This study examines the killing effect of pulsed electric fields (PEF) on four organisms suspended in a model medium Escherichia coli , Listeria innocua , Leuconostoc mesenteroides and Saccharomyces cerevisiae differ in size, shape and cell wall construction The electric field strength, pulse duration and number of pulses were varied in the ranges of 25–35 kV/cm, 2–4 μs and 20–40 pulses, respectively The results showed that S cerevisiae was the most sensitive organism with a 6-log reduction, followed by E coli with a 54-log reduction, when they were exposed to 30 kV/cm, and 20 pulses with 4 μs duration The most resistant organisms were L innocua and L mesenteroides with only a 3-log reduction, however, by increasing the parameters to 35 kV/cm and 40 pulses with 4 μs pulse duration; marked viability reductions of 8 and 7 log, respectively, were observed Heat, which is generated during the process, has limited killing effect on the cells, hence the observed reduction can be ascribed to the PEF treatment Although transmission electron microscopy of PEF treated cells did not confirm membrane damage, observations suggest that PEF treatments have profound direct or indirect effects on the intracellular organisation of microorganisms
156 citations
TL;DR: Two methods, a catch-up ELISA and a dipstick test based on the detection in urine of lipoarabinomannan, may prove valuable for rapid and simple diagnosis of TB in particular in developing countries lacking biosafety level 3 (BSL3) facilities.
144 citations
TL;DR: The results reveal that the H. pyloripopulation infecting one individual can undergo significant divergence, creating stable subclones with substantial genotypic and phenotypic differences.
Abstract: Helicobacter pylori has a very plastic genome, reflecting its high rate of recombination and point mutation. This plasticity promotes divergence of the population by the development of subclones and presumably enhances adaptation to host niches. We have investigated the genotypic and phenotypic characteristics of two such subclones isolated from one patient as well as the genetic evolution of these isolates during experimental infection. Whole-genome genotyping of the isolates using DNA microarrays revealed that they were more similar to each other than to a panel of other genotyped strains recovered from different hosts. Nonetheless, they still showed significant differences. For example, one isolate (67:21) contained the entire Cag pathogenicity island (PAI), whereas the other (67:20) had excised the PAI. Phenotypic studies disclosed that both isolates expressed adhesins that recognized human histo-blood group Lewisb glycan receptors produced by gastric pit and surface mucus cells. In addition, both isolates were able to colonize, to equivalent density and with similar efficiency, germ-free transgenic mice genetically engineered to synthesize Lewisb glycans in their pit cells (12 to 14 mice/isolate). Remarkably, the Cag PAI-negative isolate was unable to colonize conventionally raised Lewisb transgenic mice harboring a normal gastric microflora, whereas the Cag PAI-positive isolate colonized 74% of the animals (39 to 40 mice/isolate). The genomic evolution of both isolates during the infection of conventionally raised and germ-free mice was monitored over the course of 3 months. The Cag PAI-positive isolate was also surveyed after a 10 month colonization of conventionally raised transgenic animals (n = 9 mice). Microarray analysis of the Cag PAI and sequence analysis of the cagA, recA, and 16S rRNA genes disclosed no changes in recovered isolates. Together, these results reveal that the H. pylori population infecting one individual can undergo significant divergence, creating stable subclones with substantial genotypic and phenotypic differences.
130 citations
TL;DR: The ECLM European Urinalysis Guidelines discuss the complete process of clinical urine analysis and introduce guidelines to European clinical microbiologists that are designed to give the true value of themeasurand(analyzedcomponent).
TL;DR: Results show both similarities and differences in attitudes among young and old patient groups, and differences could be explained by a combination of life-cycle effects, cohort effects and expectations ensuing from the need for future health care contacts.
TL;DR: It is proved that all three TBEV subtypes are co‐circulating in Latvia and indicated that the genetic diversity of TBEv within certain geographical areas is much more complex than previously believed.
Abstract: Viruses of the tick-borne encephalitis (TBE) antigenic complex within the family Flaviviridae cause a variety of diseases, including uncomplicated febrile illness, meningoencephalitis, and hemorrhagic fever. Different domesticated animals or wildlife species often act as reservoir hosts and ixodid ticks serve as vectors. Although TBE is a serious problem in Latvia, the knowledge concerning TBE virus (TBEV) strains circulating in the country is most limited. Only two strains (Latvia-1-96 isolated from a TBE patient, and RK1424 originating from an Ixodes persulcatus tick), which belonged to the Siberian and the Far Eastern subtypes of TBEV, respectively, have previously been characterized. In the present study, we concentrated on the western and central regions of Latvia, with predominantly Ixodes ricinus ticks. Five virus strains were isolated from serum samples of patients with clinical symptoms of an acute TBE infection. Nucleotide sequences encoding the envelope (E) protein of TBEV, which were recovered from the five TBEV isolates, showed the highest level of identity to the corresponding sequences of the prototype strain Neudoerfl and other European strains of the Western TBEV subtype characterized previously. Accordingly, phylogenetic analysis placed the new Latvian isolates within the Western genetic lineage of TBEV. Taken together with earlier observations, the results proved that all three TBEV subtypes are co-circulating in Latvia and indicated that the genetic diversity of TBEV within certain geographical areas is much more complex than previously believed.
TL;DR: In this paper, the influence of carbide distribution, inclusion contents and the surface machining process on the fatigue properties of tool steels and high speed steels was investigated, and the staircase method was used to determine the fatigue strength corresponding to a life of two million cycles.
TL;DR: WD was reproduced in ser onegative lactating cows and the cows showed a more severe general diseases than seronegative calves infected concurrently, suggesting that the same strains of BCV cause natural outbreaks of calf diarrhoea and WD.
TL;DR: Linezolid is the first of a truly new class of antibiotics, the oxazolidinones, which acts as an inhibitor of bacterial protein synthesis by blocking the formation of the 70S ribosomal initiation complex and is a weak and reversible monoamine oxidase (MAO) inhibitor.
Abstract: Linezolid is the first of a truly new class of antibiotics, the oxazolidinones. It acts as an inhibitor of bacterial protein synthesis by blocking the formation of the 70S ribosomal initiation complex. Its activity is bacteriostatic against some species (e.g., enterococci) and bactericidal against others (e.g., pneumococci). The antibacterial spectrum of linezolid includes Gram-positive pathogens and some Gram-negative anaerobic species but not Gram-negative aerobes. Importantly, multi-drug resistant organisms such as methicillin-resistant staphylococci, staphylococci with reduced susceptibility to vancomycin, penicillin- and macrolide-resistant pneumococci and vancomycin-resistant enterococci are fully susceptible to linezolid. Linezolid has almost 100% bioavailability and the area under the plasma concentration curve is identical after oral and iv. administration. This enables initial oral administration of linezolid in those patients who can absorb the drug normally and also an early step-down therapy from iv. to oral. Controlled, randomised clinical studies have documented efficacy and safety of linezolid in hospital- and community-acquired pneumonia, uncomplicated and complicated skin and soft tissue infections and infections caused by vancomycin-resistant enterococci. The safety and tolerability of linezolid are advantageous. Linezolid is a weak and reversible monoamine oxidase (MAO) inhibitor and although no increased frequency of adrenergic or serotonergic adverse events has been reported, it is recommended that linezolid is used with caution in patients treated with other MAO inhibitors.
TL;DR: In this article, the selective dissolution of duplex stainless steel 2205 in acidic chloride solutions was studied in situ by electrochemical scanning tunnelling microscopy (STM) in 005 M H2SO4 + 1 M NaCl, no degradation was observed.
TL;DR: Observations suggest that antimicrobial peptides may play an important role in host defence against MDR M. tuberculosis.
Abstract: We have investigated the in vitro activity of antimicrobial peptides against Mycobacterium tuberculosis using a radiometric method and cfu determinations. PR-39, a proline-arginine-rich antibacterial peptide from porcine leucocytes, was found to be active against drug-susceptible as well as multi-drug-resistant (MDR) clinical isolates of M. tuberculosis. The activity of PR-39 was concentration dependent, with 80% growth inhibition of M. tuberculosis H37Rv at 50 mg/L. The MDR M. tuberculosis strains E1380/94 and P34/95 were less susceptible to PR-39, with 39 and 49% growth inhibition at 50 mg/L peptide, respectively, suggesting a lower susceptibility than strain H37Rv and drug-susceptible clinical isolates. Reduction of counts of M. tuberculosis H37Rv and the MDR M. tuberculosis strain E1380/94 by PR-39 indicated that the growth inhibition seen in the radiometric assay is due to a mycobactericidal effect of the peptide. These observations suggest that antimicrobial peptides may play an important role in host defence against MDR M. tuberculosis.
TL;DR: Meat, meat products, and mixed dishes were the most implicated food categories and Calicivirus, Campylobacter spp.
Abstract: Surveillance was enhanced and a retrospective interview study performed in 1998-99 to determine incidence, causes, and costs of foodborne illnesses in Uppsala, Sweden. Sixty-eight percent of the detected foodborne illness incidents were single cases, and 32% were outbreaks. Most (85%) of the incidents came to the attention of the municipal authorities through telephone calls from affected persons. Calicivirus, Campylobacter spp., and Staphyloccocus aureus were the most common etiological agents; meat, meat products, and mixed dishes were the most implicated food categories. The incidence of foodborne illness was estimated to be 38 cases per 1,000 inhabitants per year. The estimated average costs per illness were 2,164 Swedish Krona (SEK) ($246) to society and 500 SEK ($57) to the patient. The annual cost of foodborne illnesses in Sweden was estimated to be 1,082 million SEK ($123 million).
TL;DR: A prime-boost strategy that efficiently induces both humoral and cellular immune responses is demonstrated, and monkeys who first received SFV-SIVmac twice and then were boosted with MVA-Sivmac showed increased antibody responses as well as high T-cell proliferative responses.
TL;DR: In this article, the residual stresses at the surface layer of induction hardened cylindrical specimens were investigated and two microstructures, quenched-tempered and normalised, were investigated.
TL;DR: In this article, case-based reasoning (CBR) is used as a tool for selection of the material and heat treatment process from a database containing material properties of a number of steels.
TL;DR: The results showed that external oblique and erector spinae had significantly different activation patterns depending on twisting direction, which implies that work in twisted trunk postures might be a risk factor for low-back pain.
TL;DR: Stool parasites such as Blastocystis hominis, hookworm and Strongyloides stercoralis were observed both among HIV-positive and HIV-negative patients, and all three parasites were seen only in HIV- positive patients.
TL;DR: In this paper, the effect of different head coverings on air-borne transmission of bacteria and particles in the surgical area was studied during 30 strictly standardized sham operations performed in a horizontal laminar air flow (LAF) unit.
TL;DR: 2 studies have shown correlates between measurable anti-pertactin, anti-fimbriae, and anti-PT antibody levels at exposure and individual protection against pertussis, and it is suggested that postvaccination response rates may be used as surrogate markers of protection.
Abstract: Studies on serologic correlates to protection in pertussis were reviewed. Trials in the 1950s showed that agglutinogen titers correlated to protection of whole-cell vaccines, but postvaccination antibodies against pertussis toxin (PT) and against filamentous hemagglutinin did not in a later trial of acellular vaccines. However, in household studies nested in 2 recent trials, preexposure antibody levels against pertactin and against fimbriae correlated with protection against typical and mild pertussis, and anti-PT correlated only with protection against typical pertussis. These findings could be used by regulatory agencies to license pertussis vaccines. A reference laboratory for pertussis should distribute panels to control interlaboratory variation in recommended assays, and a minimal response should be set for each pertussis antigen. We conclude that 2 studies have shown correlates between measurable anti-pertactin, anti-fimbriae, and anti-PT antibody levels at exposure and individual protection against pertussis. We suggest that postvaccination response rates may be used as surrogate markers of protection.
TL;DR: Becaplermin may be a cost-effective treatment for neuropathic diabetic foot ulcers in a wide range of European settings and may even be cost saving in Sweden, Switzerland and the UK.
Abstract: Objective: The primary objective of this study was to estimate the cost effectiveness of treating diabetic foot ulcers with becaplermin (Regranex®) plus good wound care (GWC) compared with GWC alone in a variety of European healthcare settings. A secondary objective was to analyse the effect of different treatment practices on the economics of caring for diabetic foot ulcers. Design and setting: Markov-based simulation study from the perspective of a national health system. Methods: A 12-month Markov computer simulation model was used to assess the cost effectiveness in 4 European countries of treating diabetic foot ulcers with becaplermin plus GWC versus GWC alone. Transition probabilities were taken from a prospective study of 183 patients and becaplermin efficacy was based on 20-week healing rates in a recent meta-analysis of clinical trials involving 449 patients. Country-specific treatment cost data were collected in collaboration with local economic consultations and combined with the disease model to estimate the incremental cost per ulcer-free month gained. The model was then run using hypothetical low- and high-intensity resource usage profiles to investigate the economics of caring for diabetic foot ulcers. Results: Over the course of 1 year, individuals who received becaplermin plus GWC were, on average, predicted to spend an additional 0.81 months (24% longer) free of ulcers and to experience a 9% lower risk of undergoing a lower extremity amputation than individuals who received GWC alone. Consequently, becaplermin plus GWC was estimated to be net cost saving in Sweden, Switzerland and the UK. In France, the addition of becaplermin was estimated to add $US19 (1999 values) for each additional ulcer-free month gained. There were substantial intercountry differences in treatment practices and the costs of treating diabetic foot ulcers. Conclusions: Becaplermin may be a cost-effective treatment for neuropathic diabetic foot ulcers in a wide range of European settings. In Sweden, Switzerland and the UK, becaplermin may even be cost saving. Substantial intercountry differences in resource patterns appear, at least partly, to be the logical outcome of differences in unit costs.
TL;DR: A protocol for chemiluminescence detection of hantaviral antigens in infected cell foci is described, which enables reduction of incubation time of virus-infected cells and amount of needed antibody for antigen detection in foci.
TL;DR: This paper reviews research on deaf-blind individuals, primarily from behavioral and communicative points of view and some suggestions regarding learning of alphabetic codes and sign acquisition are proposed.
Abstract: This paper reviews research on deaf-blind individuals, primarily from behavioral and communicative points of view. Inclusion in the population of deaf-blind is qualified by describing a variety of ...
TL;DR: Analysis of a panel of serial patient sera showed that as the immunity matured, IgG antibodies against the recombinant glycoproteins appeared and the titers increased in the course of time, while antibodies againstThe recombinant N were present already in the acute phase in high titers.
Abstract: Puumala hantavirus (PUUV) glycoproteins G1 and G2 and nucleocapsid protein (N) were expressed in BHK-21 cells by transfection of a plasmid producing a recombinant alphavirus replicon. Coexpression of G1 and G2 from separate constructs seemed to be important for the optimal folding of the glycoproteins, as evaluated by a panel of MAbs detecting conformational epitopes. To evaluate the human antibody response against recombinant G1, G2 and N, several panels of sera were tested by immunofluorescence assay (IFA). Also human sera showed the best reactivity towards G1 and G2 coexpressed from separate transcripts (G1 + G2). Notably, only 2% of the acute sera (total number = 133) contained IgG antibodies against G1 + G2, whereas of old-immunity sera (total number = 100) 87% were G1 + G2 positive. Analysis of a panel of serial patient sera showed that as the immunity matured, IgG antibodies against the recombinant glycoproteins appeared and the titers increased in the course of time, while antibodies against the recombinant N were present already in the acute phase in high titers. The granular fluorescence pattern in PUUV IgG-IFA, associated with the acute phase of immunity, was linked to the presence of antibodies against N, whereas the diffuse fluorescence pattern associated with old-immunity, was linked to the development of antibodies against G1 + G2. The granular fluorescence pattern in PUUV IgG-IFA had a predictive value of 100% for acute PUUV infection. Weak cross-reaction with PUUV glycoproteins was observed in 36% of old-immunity DOBV-specific human sera. J. Med. Virol. 65:605–613, 2001. © 2001 Wiley-Liss, Inc.