Mikrobiologicky Ustav

Prague, Czech Republic

Mikrobiologicky Ustav

Prague, Czech Republic
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Marcos-Garcia M.,University of Salamanca | Marcos-Garcia M.,Instituto Hispano Luso Of Investigaciones Agrarias Ciale | Garcia-Fraile P.,Mikrobiologicky ustav | Filipova A.,Mikrobiologicky ustav | And 9 more authors.
Environmental Science and Pollution Research | Year: 2017

Polyhydroxyalkanoic acids (PHAs) are natural polyesters that can be used to produce bioplastics which are biodegradable. Numerous microorganisms accumulate PHAs as energy reserves. Combinations of different PHAs monomers lead to the production of bioplastics with very different properties. In the present work, we show the capability of strains belonging to various phylogenetic lineages within the genus Mesorhizobium, isolated from Lotus corniculatus nodules, to produce different PHA monomers. Among our strains, we found the production of 3-hydroxybutyrate, 3-hydroxyvalerate, 3-hydroxydodecanoate, and 3-hydroxyhexadecanoate. Most of the PHA-positive strains were phylogenetically related to the species M. jarvisii. However, our findings suggest that the ability to produce different monomers forming PHAs is strain-dependent. © 2017 Springer-Verlag Berlin Heidelberg

Objective: This study aimed to obtain recent epidemiological data on hospital-acquired pneumonia (HAP) in intensive care patients and to determine adequate empirical antimicrobial therapy. Setting: Department of Anaesthesiology, Resuscitation and Intensive Care Medicine. Patients and methods: The prospective, multicenter, observational study assessed the spectrum of detected bacterial pathogens and their resistance to antimicrobial agents. It was compared with a reference approach to initial antibiotic therapy in early- and late-onset HAP. Results: Total 317 patients were included in the study. The final patient sample comprised 201 subjects (159 males and 42 females) with a mean age of 59.9 years. Total 260 valid samples of lower respiratory tract secretions were obtained. Early- and late-onset HAP was detected in 26 (12.9%) and 175 (87.1%) patients, respectively. A total of 22 bacterial species were identified as etiological agents, with detection rates higher that 5% being noted in only 6 of them (Klebsiella pneumoniae 20.4%, Pseudomonas aeruginosa 20.0%, Escherichia coli 10.8%, Enterobacter spp. 8.1%, Staphylococcus aureus 6.2% and Burkholderia cepacia complex 5.8%). Gram-negative bacteria were most prevalent (86.1%). Patients with early-onset HAP had considerably higher prevalence of strains of Staphylococcus aureus (26.9%) and Haemophilus influenzae (15.4%). In late-onset HAP, most dominant were the strains of Pseudomonas aeruginosa (21.8%) and Klebsiella pneumoniae (21.4%). Most pathogens causing HAP (74.0%) were shown to have a unique restriction profile. Adequate initial empirical antibiotic therapy was noted in 59.7% of patients. Conclusion: The reference approach to initial empirical antibiotic therapy of early- and late-onset HAP was consistent with the spectrum of bacterial pathogens and their susceptibility to antimicrobial agents.

Skalsky I.,Klinika Kardiovaskularni Chirurgie | Szarszoi O.,Klinika Kardiovaskularni Chirurgie | Filova E.,Fyziologicky Ustav | Parizek M.,Fyziologicky Ustav | And 15 more authors.
Cor et Vasa | Year: 2011

Aim: Autologous venous grafts such as coronary artery bypass grafts often develop intimal hyperplasia resulting in stenoses and occlusions. The aim of our study was to prevent the development of intimal hyperplasia using a novel perivascular system allowing for long-term release of sirolimus. Method: The controlled-release system comprises a polyester mesh coated with a sirolimus-eluting copolymer of L lactic acid and ε-caprolactone system designed to be wrapped around an autologous venous graft during its implantation. In vitro sirolimus release and its effects on smooth muscle and endothelial cells were assessed. The sirolimus controlled-release mesh was implanted into the common carotid arteries of rabbits with subsequent assessment of venous graft neointimal hyperplasia at 3 and 6 weeks. Results: In vitro, the copolymer-coated polyester mesh released sirolimus over a period of 6 weeks. Mesh-eluted sirolimus inhibited the growth of smooth muscle and endothelial cells in seven-day in vitro experiments. After seven days of sirolimus release from the mesh, smooth muscle and endothelial cell counts decreased by 29% and 75%, respectively, with the cells maintaining high viability. Implantation of the sirolimus-release mesh to rabbits resulted in a decrease in intimal thickness by 47% and 56% at 3 and 6 weeks, respectively, compared with the venous intima. After implantation of a sirolimus-free mesh, intimal thickness declined by 35% and 46% at 3 and 6 weeks, respectively. Conclusion: A sirolimus controlled-release system intended for periadventitial use in autologous venous grafts inhibited the growth of smooth muscle cells in vitro and precluded the development of neointimal hyperplasia in vivo in rabbits. Hence, the perivascular sirolimus-eluting mesh holds promise for preventing the development of stenoses and occlusions in autologous vascular grafts. © 2008-2010 Medical Tribune Cz, s. r. o.

Klusackova P.,Klinika Pracovniho Lekarstvi 1. LF UK A VFN | Lebedova J.,Klinika Pracovniho Lekarstvi 1. LF UK A VFN | Fenclova Z.,Klinika Pracovniho Lekarstvi 1. LF UK A VFN | Vlckova S.,Klinika Pracovniho Lekarstvi 1. LF UK A VFN | And 5 more authors.
Alergie | Year: 2013

Diagnostics of occupational asthma is based on positive results of bronchoprovocation tests (BPT) with occupational allergens. It is necessary to look for new methods which could make the diagnostics more precise. Twenty persons were tested with suspicion on occupational asthma. Except standard tests also leukotrienes (LT) B4, C4, D4, E 4, 8-isoprostane, malondialdehyde and 4-hydroxy-trans-2-nonenal in breath condensate, plasma and urine were analyzed. Examination was performed before BPT, after the non-specific bronchoprovocation test (nBPT) with methacholine and after specific bronchoprovocation tests with occupational allergens (sBPT). Specific bronchoprovocation tests were positive in 10 persons. In the group of patients with positive results of sBPT more frequently nBPT was positive (p = 0.002). Significant difference was found between groups with negative and positive results of sBPT in pH of breath condensate (p = 0.012). Within the group with positive sBPT significant decrease of 8-isoprostane was found in plasma after nBPT and sBPT (p = 0.006 a 0.049) compared to the basal value and significant increase of LTE4 in plasma after sBPT compared to the value after nBPT (p = 0.037).

Bazovska S.,Ustav epidemiologie | Durovska J.,I. neurologicka klinika | Pancak J.,I. neurologicka klinika | Zaborska M.,Mikrobiologicky ustav | Derdakova M.,Parazitologicky ustav SAV v Kosiciach
Epidemiologie, Mikrobiologie, Imunologie | Year: 2011

A case report is presented of a 55-year-old patient diagnosed with a demyelinating disease of unclear etiology. The patient had Lyme borreliosis in 2004. Specific IgG antibodies against B. burgdorferi s. l. were detected in the serum. Intrathecal antibodies were not found in the cerebrospinal fluid, but the presence of B. garinii DNA was confirmed by PCR analysis. It can be hypothesized that the borrelial persistence in the body may have been one of the triggers of the autoimmune process resulting in demyelination of the central nervous system (CNS).

Ballay R.,I. ortopedicka klinika | Landor I.,I. ortopedicka klinika | Ruzicka F.,Mikrobiologicky ustav | Melichercik P.,I. ortopedicka klinika | And 2 more authors.
Acta Chirurgiae Orthopaedicae et Traumatologiae Cechoslovaca | Year: 2016

PURPOSE OF THE STUDY: The alloplastic materials currently used for protective surface layers on implants were tested in vitro under microbiological laboratory conditions by contamination with microbial agents most frequently found in deep infection of total joint replacements. The objective was to find out how the resistance to bacterial colonisation was related to different surface finishes. MATERIAL AND METHODS: Each of 14 samples of alloplastic material currently used in the manufacture of orthopaedic implants was inoculated with each of the group of microorganisms most frequently infecting joint replacements; these were Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Enterococcus faecalis and Escherichia coli. At 24 hours of incubation, biofilms produced on sample surfaces were collected, stained with crystalline violet and assessed by spectrophotometry. The average value of biofilm absorbances (AV595) for the group of microorganism tested was taken as a basic characteristic of each material sample indicating its sensitivity to bacterial. RESULTS: Of the metal materials with smooth surface finish, Vitalium (AV595, 0.368) showed the lowest affinity to microbial colonisation; next was titanium (AV595, 0.459) and steel (AV595, 0.505). A significant increase in sensitivity to bacterial colonisation was recorded in all types of surface finish of steel (AV595, 0.571) and in titanium alloy with a rough surface texture (AV595, 0.737 to 1.676); p < 0.05. Porous titanium surfaces significantly increased material affinity to colonisation. DISCUSSION: Our study had certain limitations concerning in vitro evaluation of porous surfaces that have high affinity to bacterial colonisation. Porous titanium, and its hydroxyapatite layer in particular, considerably promotes osteoblast colonisation of the surface as well as implant osseointegration in the bone bed. Microorganisms therefore have no room for surface colonisation. Problematic may remain the surface parts outside contact with bone that keep their affinity to bacterial colonisation. CONCLUSIONS: The material of choice for cemented implants is Vitalium which, of all metal surfaces, has the lowest sensitivity to bacterial colonisation. The materials of choice for cementless implants are titanium alloys. However, an osteoactive surface not in contact with bone remains a problem. On the one hand, its roughness and porosity are crucial to good osseointegration, on the other hand, its affinity to bacterial colonisation is high. © 2016. Galen s.r.o. All rights reserved.

Cernohorska L.,Mikrobiologicky ustav
Epidemiologie, mikrobiologie, imunologie : casopis Spolecnosti pro epidemiologii a mikrobiologii Ceské lékarské spolecnosti J.E. Purkyne | Year: 2010

Altogether 118 Pseudomonas aeruginosa strains isolated from urine of patients with urinary tract infection were tested by the disk diffusion method for susceptibility to ciprofloxacin, ofloxacin, gentamicin, amikacin, colistin, meropenem, imipenem, piperacillin/tazobactam and ceftazidime. All strains were also screened for biofilm formation using a modified Christensen method. Eighty-eight, i.e., 74.6%, of the tested strains were resistant to ofloxacin, 86 (72.9%) to ciprofloxacin and 70 (59.3%) to gentamicin. Forty strains (33.9%) were resistant to imipenem, 42 strains (35.6%) to meropenem, 14 strains (11.9%) to amikacin, 2 strains (1.7%) to colistin, 35 strains (29.7%) to piperacillin/tazobactam and 41 strains (34.7%) to ceftazidime. Co-resistance to ofloxacin, ciprofloxacin and gentamicin was detected in 67 strains (56.8%) while 12 strains (10.2%) were resistant to most tested antibiotics, with the exception of amikacin and colistin. Biofilm formation was found in 41 strains (34.7%), more precisely in 23 of 46 inpatient strains and 18 of 72 outpatient strains. Eight (66.6%) of 12 polyresistant strains were biofilm producers.

Nosocomial infections associated with biofilm formation have been a serious problem in recent years. Up to 32% of them are urinary tract infections in patients with long-dwelling catheters. Catheters represent an ideal surface for bacterial adhesion, facilitating easier colonization of the urinary tract. Important pathogens causing these infections are bacteria of the genus Proteus that colonize catheters not only by biofilm formation but also using other virulence factors. Those were developed for survival in the host organism and are also used by bacteria to infect the host or fight the defence mechanisms. The study focused on the following selected virulence factors: swimming, swarming and twitching motility, swarming motility across various types of urinary catheters, biofilm formation in various media, formation of biofilm on catheters, haemolysin and urease production. A total of 102 strains isolated from urinary catheters and 50 strains isolated from stools were analyzed. In twitching motility, a difference between strains isolated from catheters and stools was statistically significant (p = 0.012). In swimming and swarming motility, the difference was not significant (p = 0.074 and p = 0.809, respectively). In motility across various catheter types, a statistically significant difference was found in strains isolated from both catheters and stools (p ≪ 0.01 in both cases). For biofilm formation analyses, BHI and BHI with 4% glucose were used. In BHI, biofilm was produced by all strains, with 65% of catheter strains and 88% of strains from stools being strong producers. Similarly, all strains produced biofilm in BHI with 4% glucose, with strong producers in 94% and 92% of strains isolated from catheters and stools, respectively. In formation of biofilm on catheters, there was a statistical difference between strains from catheters and stools (p = 0.00008). All strains isolated from both catheters and stools produced urease; no difference in urease production was statistically significant (p = 0.653). On agar with washed sheep erythrocytes, haemolysin production was not detected in any of the isolated strains. The quantitative method using horse erythrocytes revealed haemolysis production in three strains isolated from catheters.

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