Host-specific Cryptosporidium, Giardia and Enterocytozoon bieneusi in shelter dogs from central Europe

Cryptosporidium spp., Giardia intestinalis and microsporidia are unicellular opportunistic pathogens that can cause gastrointestinal infections in both animals and humans. Since companion animals may serve as a source of infection, the aim of the present screening study was to analyse the prevalence of these intestinal protists in fecal samples collected from dogs living in 10 animal shelters in central Europe (101 dogs from Poland and 86 from the Czech Republic), combined with molecular subtyping of the detected organisms in order to assess their genetic diversity. Genus-specific polymerase chain reactions were performed to detect DNA of the tested species and to conduct molecular subtyping in collected samples, followed by statistical evaluation of the data obtained (using χ2 or Fisher's tests). The observed prevalence was 15.5, 10.2, 1 and 1% for G. intestinalis, Enterocytozoon bieneusi, Cryptosporidium spp. and Encephalitozoon cuniculi, respectively. Molecular evaluation has revealed the predominance of dog-specific genotypes (Cryptosporidium canis XXe1 subtype; G. intestinalis assemblages C and D; E. cuniculi genotype II; E. bieneusi genotypes D and PtEbIX), suggesting that shelter dogs do not pose a high risk of human transmission. Interestingly, the percentage distribution of the detected pathogens differed between both countries and individual shelters, suggesting that the risk of infection may be associated with conditions typical of a given location.

Genetic diversity of Cryptosporidium spp., Encephalitozoon spp. and Enterocytozoon bieneusi in feral and captive pigeons in Central Europe

Cryptosporidium spp., Enterocytozoon bieneusi and Encephalitozoon spp. are the most common protistan parasites of vertebrates. The results show that pigeon populations in Central Europe are parasitised by different species of Cryptosporidium and genotypes of microsporidia of the genera Enterocytozoon and Encephalitozoon. A total of 634 and 306 faecal samples of captive and feral pigeons (Columba livia f. domestica) from 44 locations in the Czech Republic, Slovakia and Poland were analysed for the presence of parasites by microscopy and PCR/sequence analysis of small subunit ribosomal RNA (18S rDNA), 60 kDa glycoprotein (gp60) and internal transcribed spacer (ITS) of SSU rDNA. Phylogenetic analyses revealed the presence of C. meleagridis, C. baileyi, C. parvum, C. andersoni, C. muris, C. galli and C. ornithophilus, E. hellem genotype 1A and 2B, E. cuniculi genotype I and II and E. bieneusi genotype Peru 6, CHN-F1, D, Peru 8, Type IV, ZY37, E, CHN4, SCF2 and WR4. Captive pigeons were significantly more frequently parasitised with screened parasite than feral pigeons. Cryptosporidium meleagridis IIIa and a new subtype IIIl have been described, the oocysts of which are not infectious to immunodeficient mice, whereas chickens are susceptible. This investigation demonstrates that pigeons can be hosts to numerous species, genotypes and subtypes of the studied parasites. Consequently, they represent a potential source of infection for both livestock and humans.

Microsporidia (Encephalitozoon cuniculi) in Patients with Degenerative Hip and Knee Disease, Czech Republic

Total joint arthroplasty is a commonly used surgical procedure in orthopedics. Revision surgeries are required in >10% of patients mainly because of prosthetic joint infection caused by bacteria or aseptic implant loosening caused by chronic inflammation. Encephalitozoon cuniculi is a microsporidium, an obligate intracellular parasite, capable of exploiting migrating proinflammatory immune cells for dissemination within the host. We used molecular detection methods to evaluate the incidence of E. cuniculi among patients who had total hip or knee arthroplasty revision. Out of 49 patients, E. cuniculi genotypes I, II, or III were confirmed in joint samples from 3 men and 2 women who had implant loosening. Understanding the risks associated with the presence of microsporidia in periprosthetic joint infections is essential for proper management of arthroplasty. Furthermore, E. cuniculi should be considered a potential contributing cause of joint inflammation and arthrosis.

Horse-Specific Cryptosporidium Genotype in Human with Crohn's Disease and Arthritis

We identified an unusual subtype of a Cryptosporidium sp. horse genotype as the cause of cryptosporidiosis in a 13-year-old girl in Poland who was undergoing immunosuppressive treatment for juvenile rheumatoid arthritis and Crohn’s disease. The same subtype was identified in a horse the girl had ridden.

Pneumocystis jirovecii Colonization in Preterm Newborns With Respiratory Distress Syndrome

We describe the prevalence of Pneumocystis jirovecii in mother-infant pairs of very low birth weight newborns <32 weeks gestation. Molecular and microscopic methods were used for detection of P. jirovecii in patients' specimens. Pneumocystis DNA was detected in 8 nasopharyngeal aspirates (14%) of 56 newborns and in 7 oral washes (21%) of 34 mothers. Pneumocystis detection immediately after birth suggests the possibility of its transplacental transmission. Compared to noncolonized infants, more frequent occurrence of bronchopulmonary dysplasia was seen in colonized infants (P = .02), suggesting a potential clinical importance of this pathogen in abnormal lung development.

Encephalitozoon cuniculi and Extraintestinal Microsporidiosis in Bird Owners

We identified Encephalitozoon cuniculi genotype II parasites as a cause of extraintestinal microsporidiosis in 2 owners of birds also infected with E. cuniculi. Patients experienced long-lasting nonspecific symptoms; the disease course was more progressive in a patient with diabetes. Our findings suggest direct bird-to-human transmission of this pathogen.

Enterocytozoon Bieneusi Infects Children With Inflammatory Bowel Disease Undergoing Immunosuppressive Treatment

Objectives: Patients with inflammatory bowel disease (IBD) are susceptible to intestinal opportunistic infections due to both defective mucosal immunity and altered immune response resulting from immunosuppressive treatment. Microsporidia infecting the gastrointestinal tract and causing diarrhoea can potentially affect the course of IBD.

Methods: Stool samples (90 IBD children and 121 healthy age-matched controls) were screened for Encephalitozoon spp. and Enterocytozoon bieneusi by microscopy and polymerase chain reaction followed by sequencing.

Results:E. bieneusi genotype D was found in seven out of 90 (7.8%) IBD children. No children from the control group were infected, making the pathogen prevalence in the IBD group significant (P = 0.002). Furthermore, infection was confirmed only in patients receiving immunosuppressive treatment (P = 0.013).

Conclusions: Children with IBD are at risk of intestinal E. bieneusi infection, especially when receiving immunosuppressive treatment. Therefore, microsporidia should be considered as a significant infectious agent in this group of patients.

Cryptosporidium baileyi Pulmonary Infection in Immunocompetent Woman with Benign Neoplasm

Cryptosporidium baileyi, a bird-specific parasite, infects gastrointestinal, pulmonary, and urinary tracts of its host. We report on a C. baileyi infection associated with pulmonary hamartoma in an immunocompetent patient in Poland. Further work is needed to investigate the association between Cryptosporidium infections and tumors.

Raw Goat's Milk, Fresh and Soft Cheeses as a Potential Source of Encephalitozoon cuniculi

The aim of this work was to evaluate the effect of pasteurization and coagulation during goat cheese production on the infectivity of Encephalitozoon cuniculi spores for immunodeficient (SCID, CD4^-/-, and CD8^-/-) and immunocompetent (BALB/c and C57BL/6) mice. Goat milk and fecal samples were screened for the presence and quantity of microsporidial DNA using molecular methods. Experimentally produced cheese from E. cuniculi-enriched goat milk or goat cheese purchased from retail producers was fed with experimental mice susceptible to E. cuniculi infection. The mice were sacrificed in the presumed acute phase of infection and samples of their tissues were subject to molecular detection of specific E. cuniculi DNA. Specific DNA of E. cuniculi genotype II was detected in feces and milk of three out of 99 goats kept on 6 farms in the Czech Republic. Under experimental conditions, spores of E. cuniculi genotype II remained viable in artificially enriched fresh cheese and were able to cause infection in laboratory mice. E. cuniculi genotype I and II DNA were detected in eight of the nine goat cheeses purchased from various producers/breeders in the Czech Republic and these cheeses were able to develop infection in both immunodeficient and immunocompetent mice. The results of these experiments showed that spores of E. cuniculi genotype I and II are able to remain viable after cheese processing and thus fresh and soft cheeses should be considered a potential source of microsporidia.

Occurrence and genetic diversity of Cryptosporidium spp. in wild foxes, wolves, jackals, and bears in central Europe

Parasites of the genus Cryptosporidium Tyzzer, 1910 are one of the most common protistan parasites of vertebrates. Faecal samples from 179 red foxes (Vulpes vulpes [Linnaeus]), 100 grey wolves (Canis lupus Linnaeus), 11 golden jackals (Canis aureus Linnaeus), and 63 brown bears (Ursus arctos Linnaeus) were collected in the Czech Republic, Poland and Slovakia. Samples were examined for the presence of Cryptosporidium spp. using microscopy and PCR/sequence analysis. Phylogenetic analysis based on the small subunit ribosomal RNA (SSU), actin and 60-kDa glycoprotein (gp60) genes using the maximum likelihood method revealed the presence of Cryptosporidium tyzzeri Ren, Zhao, Zhang, Ning, Jian et al., 2012 (n = 1) and C. andersoni Lindsay, Upton, Owens, Morgan, Mead et Blackburn, 2000 (n = 2) in red foxes, C. canis Fayer, Trout, Xiao, Morgan, Lai et Dubey, 2001 (n = 2) and C. ubiquitum Fayer, Santín et Macarisin, 2010 (n = 2) in grey wolves, and C. galli Pavlásek, 1999 in brown bears (n = 1) and red foxes (n = 1). Subtyping of isolates of C. ubiquitum and C. tyzzeri based on sequence analysis of gp60 showed that they belong to the XIId and IXa families, respectively. The presence of specific DNA of C. tyzzeri, C. andersoni and C. galli, which primarily infect the prey of carnivores, is probably the result of their passage through the gastrointestinal tract of the carnivores. Finding C. ubiquitum XIId in wolves may mean broadening the host spectrum of this subtype, but it remains possible this is the result of infected prey passing through the wolf - in this case deer, which is a common host of this parasite. The dog genotype of C. canis was reported for the first time in wolves.

Encephalitozoon cuniculi Genotype II Concentrates in Inflammation Foci

Background

Microsporidia of the genus Encephalitozoon are generally connected with severe infections with lethal outcome in immunodeficient hosts. In immunocompetent hosts, microsporidiosis typically establishes a balanced host–parasite relationship that produces minimal clinically overt disease. Although the alimentary tract represents one of the main primary target tissues, the mechanisms of reaching other tissues during systemic microsporidian infections remain unclear.

Methods

In the present study, we tested the relation between inflammation induction in immunocompetent and immunodeficient mice and the presence of spores of E. cuniculi genotype II in selected organs and in fecal specimens by using molecular and histology methods.

Results

We reported the positive connection between inflammation induction and the significant increase of E. cuniculi genotype II occurrence in inflammation foci in both immunocompetent BALB/c and immunodeficient severe combined immunodeficient (SCID) mice in the acute phase of infection and the re-activation of latent microsporidial infection following inflammation induction in immunocompetent mice.

Conclusion

The results imply possible involvement of immune cells serving as vehicles transporting E. cuniculi genotype II purposefully across the whole host body towards inflammation. With increasing number of records of infections, it is necessary to reconsider microsporidia as agents responsible for various pathologies. The elucidation of possible connection with pro-inflammatory immune responses represents an important challenge with consequences for human health and development of therapeutic strategies.

The First Evidence of Cryptosporidium meleagridis Infection in a Colon Adenocarcinoma From an Immunocompetent Patient

Objectives: The potential linkage between Cryptosporidium spp. infection and colorectal human cancer was suggested by limited reports showing higher prevalence of C. parvum and C. hominis in patients with colon cancer. Here we conducted research concerning presence of Cryptosporidium spp. in malignant tissue collected from patients with colorectal cancer.

Methods: Cancerous colon tissue samples collected from 145 non-HIV infected patients with colorectal cancer were screened for Cryptosporidium spp. by immunofluorescence antibody test and genus-specific nested polymerase chain reaction followed by sequencing.

Results: Screened pathogen was found in cancerous tissue originating from immunocompetent man with colon adenocarcinoma. Genotyping revealed presence of Cryptosporidium meleagridis. The presence of Cryptosporidium life cycle stages (oocysts and endogenous stages) in colon carcinoma tissue was confirmed by genus-specific FITC-labeling.

Conclusions: Herein, we report on a C. meleagridis infection of a colon adenocarcinoma in an immunocompetent patient. This is the first report of C. meleagridis infection in the human colon and first evidence of active development of this species in cancer tissue.

Diversity of Cryptosporidium spp. in Apodemus spp. in Europe

The genetic diversity of Cryptosporidium spp. in Apodemus spp. (striped field mouse, yellow-necked mouse and wood mouse) from 16 European countries was examined by PCR/sequencing of isolates from 437 animals. Overall, 13.7% (60/437) of animals were positive for Cryptosporidium by PCR. Phylogenetic analysis of small-subunit rRNA, Cryptosporidium oocyst wall protein and actin gene sequences showed the presence of Cryptosporidium ditrichi (22/60), Cryptosporidium apodemi (13/60), Cryptosporidium apodemus genotype I (8/60), Cryptosporidium apodemus genotype II (9/60), Cryptosporidium parvum (2/60), Cryptosporidium microti (2/60), Cryptosporidium muris (2/60) and Cryptosporidium tyzzeri (2/60). At the gp60 locus, novel gp60 families XVIIa and XVIIIa were identified in Cryptosporidium apodemus genotype I and II, respectively, subtype IIaA16G1R1b was identified in C. parvum, and subtypes IXaA8 and IXcA6 in C. tyzzeri. Only animals infected with C. ditrichi, C. apodemi, and Cryptosporidium apodemus genotypes shed oocysts that were detectable by microscopy, with the infection intensity ranging from 2000 to 52,000 oocysts per gram of faeces. None of the faecal samples was diarrheic in the time of the sampling.

Dual infection of urinary tract with Enterocytozoon bieneusi and Encephalitozoon cuniculi in HIV/AIDS patients

Microsporidia are emerging pathogens which cause an opportunistic infections in immunocompromised patients, especially those with AIDS. Intestinal microsporidiosis is the most recognized infection, whereas urinary tract infections caused by microsporidia are rarely paid attention to either due to their subclinical course or diagnostic difficulties. In this report dual microsporidial infection of urinary tract, caused by Enterocytozoon bieneusi and Encephalitozoon cuniculi was described in HIV/AIDS patients under cART therapy. Since microsporidiosis can cause severe complications or even death in immunosuppressed patients, our results suggest that microsporidial infection should be included in routine investigation of HIV-positive patients, even asymptomatic.

Prevalence and genotyping of Pneumocystis jirovecii in renal transplant recipients-preliminary report

Pneumocystis jirovecii is an opportunistic fungus occurring in human lungs. The group at highest risk consists of HIV-infected and non-HIV-infected immunosuppressed individuals. In these patients, P. jirovecii infection may lead to Pneumocystis pneumonia; it may, however, persist also in an asymptomatic form. This study aimed to determine the prevalence of P. jirovecii and potential risk factors for infection in a group of renal transplant recipients and to characterize the genetic diversity of this fungus in the studied population. Sputum specimens from 72 patients were tested for presence of P. jirovecii using immunofluorescence microscopy, as well as nested PCR targeting the mtLSU rRNA gene. Genotyping involving analysis of four loci—mtLSU rRNA, CYB, DHPS, and SOD—was used to characterize the diversity of the detected organisms. Pneumocystis DNA was detected in eight (11.11%) patients. It has been shown that low eosinophil count and dual immunosuppressive treatment combining prednisone and calcineurin inhibitors are potential risk factors for colonization. Analysis of genotype distribution showed an association of the wild-type genotype of mtLSU rRNA with lower average age of patients and shorter time after kidney transplantation. Furthermore, CYB 2 genotype was detected only in patients with the ongoing prophylaxis regimen. In conclusion, renal transplant recipients are at risk of Pneumocystis colonization even a long time after transplantation. The present preliminary study identifies specific polymorphisms that appear to be correlated with certain patient characteristics and highlights the need for deeper investigation of these associations in renal transplant recipients.

Symptomatic respiratory Encephalitozoon cuniculi infection in renal transplant recipients

OBJECTIVES

Encephalitozoon spp. and Enterocytozoon bieneusi are intracellular parasitic fungi from the phylum Microsporidia, which initially localize to the intestine. As opportunistic pathogens, Encephalitozoon spp. in particular can disseminate to the respiratory tract, among other locations. Patients on life-long immunosuppression are at higher risk of such infections, mostly symptomatic.

METHODS

Sputum samples and bronchial washings from 72 renal transplant recipients and 105 patients with various respiratory diseases were screened for Encephalitozoon spp. and E. bieneusi by microscopic examination and genus-specific nested PCR followed by genotyping.

RESULTS

A total of 8.3% (6/72) of immunosuppressed renal transplant recipients and 1.9% (2/105) of patients with various respiratory diseases, both immunocompetent and immunosuppressed, were positive for respiratory microsporidial infection. All six transplant recipients were Encephalitozoon cuniculi-positive by PCR/sequencing and five of them suffered from respiratory symptoms. The presence of microsporidial spores was also confirmed microscopically in three of the transplant recipients. Of the two immunocompetent patients with various respiratory diseases, one had an E. cuniculi infection, while the second had an E. bieneusi infection.

CONCLUSIONS

Life-long immunosuppression in renal transplant recipients increases the risk of respiratory infection by E. cuniculi. Microsporidia should be screened in respiratory samples of these patients, particularly when they have respiratory symptoms.

Concurrent Infection of a Young Tourist by Hookworm and Strongyloides Stercoralis During Low Budget Travel in Southeast Asia

Strongyloidiasis and hookworm infections are neglected helminth diseases widespread in tropical and subtropical areas. In humans, particularly in immunocompromised patients infections potentially may lead to the life-threatening clinical conditions involving the respiratory as well as gastrointestinal systems. The increased number of tourists travelling to tropical regions is associated with more frequent infection with parasites such as Strongyloides and hookworm. The infection takes place when filariform larvae penetrate the skin exposed to soil, than migrate through the lungs and finally reach the intestine. Travelers are often not aware of how they could get infected. Physicians may suspect strongyloidiasis and hookworm infections in tourists with diarrhea returning from endemic areas, especially when an elevated eosinophilia is observed. In the literature there are many reports about the presence of parasites in indigenous communities, but very few are available regarding travelers. This paper describes a dual infection with hookworm and Strongyloides stercoralis in a young female tourist returning from Southeast Asia. To our knowledge, this is the first report of hookworm and Strongyloides stercoralis infection in a tourist from Europe, acquired in an endemic area.

Zoonotic microsporidia in dogs and cats in Poland

This study investigated the prevalence, genetic diversity, and zoonotic concerns of microsporidia in household dogs and cats in Poland. A total of 126 (82 dogs and 44 cats) fecal specimens were analyzed for the presence of specific DNA of Enterocytozoon bieneusi and Encephalitozoon spp. using a nested PCR protocol amplifying the internal transcribed spacer region of the rRNA gene. Microsporidia were found in 10 (7.9%) out of the 126 examined stool samples. Of the 82 dogs, 4 (4.9%) and 2 (2.4%) were positive for E. bieneusi (genotypes D and PtEbIX) and Encephalitozoon cuniculi genotype II, respectively. Of the 44 cats, 4 (9.1%) were positive for E. bieneusi (genotypes PtEbIX and eb52). Additionally, one cat (2.3%) was concurrently infected with E. bieneusi (PtEbIX) and E. cuniculi (genotype II). Considering that all detected microsporidia in dogs and cats have been previously associated with human microsporidiosis, companion animals may be a potential source of microsporidia infections in humans.

Anti-enterococcal activities of pentacyclic triterpenes

BACKGROUND

Asiatic (AA) and ursolic (UA) acids are widely studied phytochemicals, but their antimicrobial properties are still poorly understood. Therefore our research has focused on their activity against uropathogenic Enterococcus faecalis strains.

OBJECTIVES

The aim of this research was to determine the influence of AA and UA on the growth, cell morphology, virulence factors and biofilm formation by E. faecalis strains.

MATERIAL AND METHODS

AA and UA were purchased from Sigma-Aldrich. E. faecalis strains were isolated from the urine samples of patients with urinary tract infections. The strains were checked for the presence of virulence genes using the PCR method. Their antimicrobial susceptibility was performed using the disc diffusion method. The MICs of triterpenes were determined using the broth microdilution method. The hydrophobicity of cells was established by salt aggregation test. Lipase and lecithinase activities were determined by using an agar medium containing egg yolk emulsion. DNase agar was used for the detection of DNase synthesis. Hemolytic activity was established using a sheep-blood agar. Todd-Hewitt agar medium containing gelatin was used for determination of gelatinase activity. The anti-biofilm activity of asiatic acid and ursolic acid was tested on polystyrene microtiter plates. It was examined using time-kill and biofilm assays.

RESULTS

Reduction of growth and enzyme synthesis after exposure of E. faecalis to the acids was observed. None of the acids changed the hydrophobicity of bacteria. Stronger anti-biofilm activity was observed when the bacteria were incubated with AA. Thus, reduction of both the survival and the virulence factors will make bacteria less infectious.

CONCLUSIONS

Based on the results obtained, we can assume that the triterpenes investigated should be considered natural components of a human diet rather than as antibacterial agents used on their own.

Survey for Zoonotic Microsporidian Pathogens in Wild Living Urban Rooks (Corvus frugilegus)

Microsporidia are opportunistic pathogens in nature infecting all animal phyla. There is a potential risk of microsporidian spores transmission from urban rooks inhabiting some metropolitan cities to people through casual interactions. The aim of this study was to identify microsporidia species in the droppings of rooks in Wroclaw, Poland. A total of 15 collective sets of droppings were examined using nested-PCR method. Amplification of ITS rRNA gene revealed the presence of Enterocytozoon bieneusi D, Peru 6, and Encephalitozoon hellem 1A genotypes. This study indicates that excreta of urban rooks can be an important source of human infection with these pathogens.

Cryptosporidium meleagridis infection: the first report in Poland of its occurrence in an HIV-positive woman

Cryptosporidium is an opportunistic protozoan parasite that can cause severe diarrhoea in immunocompromised patients. The transmission of this pathogen in humans and animals is not fully understood. C. meleagridis, originally described in birds, is the only Cryptosporidium species known to naturally infect mammalian and avian species. This study documents the first detection of C. meleagridis in an HIV-infected woman in Poland.

Study of the impact of cranberry extract on the virulence factors and biofilm formation by Enterococcus faecalis strains isolated from urinary tract infections

Drinking of cranberry fruit juice and application of commercial preparations containing the cranberry extracts are recommended in the prevention and treatment of urinary tract infections (UTIs), especially in women with recurrent UTIs. Many studies focus on the activity of cranberries against uropathogenic Escherichia coli (E. coli) strains. However, the knowledge of the cranberry effect on Gram-positive Enterococcus faecalis (E. faecalis) is limited. Therefore, the aim of our study was to establish the activity of commercial concentrated cranberry extract on the growth, virulence factors and biofilm formation of E. faecalis strains isolated from urine. Minimal inhibitory concentrations (MICs) of cranberry extract were determined by the broth microdilution method. Disc diffusion method was used to determine antimicrobial susceptibility. The impact of cranberry extract on bacterial survival, hydrophobicity, synthesis of lipase, lecithinase, DNase, hemolysin, gelatinase and biofilm mass was determined. Results show that cranberry extract inhibits the growth, enzymatic activities of bacteria and limits biofilm formation. The antibacterial activities of the studied cranberry extract confirm that it could be successfully used in prevention of UTIs caused by E. faecalis.

Pentacyclic triterpenes combined with ciprofloxacin help to eradicate the biofilm formed in vitro by Escherichia coli

BACKGROUND & OBJECTIVES

Ciprofloxacin is commonly used in clinical practice for the treatment of recurrent urinary tract infections caused by Escherichia coli. However, very often these recurrent infections are due to a failure in a complete eradication of the microorganisms colonizing the urinary tract, especially in catheterized patients. To enhance the bactericidal activity of ciprofloxacin against biofilm-forming uropathogenic E. coli (UPECs), we examined its effect in combination with two pentacyclic triterpenes - asiatic and ursolic acids.

METHODS

The anti-biofilm activity of ciprofloxacin and pentacyclic triterpenes - asiatic acid (AA) and ursolic acid (UA), as well as their synergistic effect were tested on two types of surfaces - polystyrene microtiter plates and silicone catheters. It was investigated using the time-killing and biofilm assays.

RESULTS

a0 nti-biofilm activity of ciprofloxacin was not observed on microtiter plates or on the catheters. Ciprofloxacin combined with ursolic acid inhibited the biofilm formation on microtitre plates. This mixture, however, did not express such a strong activity against the synthesis of biofilm on the surface of catheters. Ciprofloxacin combined with asiatic acid had very weak inhibiting effect on the synthesis of biofilm mass on microtitre plates as well as on the catheters. Despite this, both mixtures - ciprofloxacin and asiatic acid, as well as ciprofloxacin and ursolic acid, exhibited strong and significant impact on the eradication of mature biofilm (P < 0.05).

INTERPRETATION & CONCLUSIONS

Although ciprofloxacin is recommended in the treatment of urinary tract infections caused by UPECs, but its efficacy is arguable. Subinhibitory concentrations of ciprofloxacin did not inhibit the formation of biofilm. Pentacyclic triterpenes used in combination with ciprofloxacin enhanced its anti-biofilm effectiveness. However, this anti-biofilm activity was found to depend on the type of surface on which biofilm was formed.

Medicinal plants extracts affect virulence factors expression and biofilm formation by the uropathogenic Escherichia coli

Medicinal plants are an important source for the therapeutic remedies of various diseases including urinary tract infections. This prompted us to perform research in this area. We decided to focus on medicinal plants species used in urinary tract infections prevention. The aim of our study was to determine the influence of Betula pendula, Equisetum arvense, Herniaria glabra, Galium odoratum, Urtica dioica, and Vaccinium vitis-idaea extracts on bacterial survival and virulence factors involved in tissue colonization and biofilm formation of the uropathogenic Escherichia coli rods. Qualitative and quantitative analysis of plant extracts were performed. Antimicrobial assay relied on the estimation of the colony forming unit number. Hydrophobicity of cells was established by salt aggregation test. Using motility agar, the ability of bacteria to move was examined. The erythrocyte hemagglutination test was used for fimbriae P screening. Curli expression was determined using YESCA agar supplemented with congo red. Quantification of biofilm formation was carried out using a microtiter plate assay and a spectrophotometric method. The results of the study indicate significant differences between investigated extracts in their antimicrobial activities. The extracts of H. glabra and V. vitis-idaea showed the highest growth-inhibitory effects (p < 0.05). Surface hydrophobicity of autoaggregating E. coli strain changed after exposure to all plant extracts, except V. vitis-idaea (p > 0.05). The B. pendula and U. dioica extracts significantly reduced the motility of the E. coli rods (p < 0.05). All the extracts exhibited the anti-biofilm activity.

Comparison of the effects of subinhibitory concentrations of ciprofloxacin and colistin on the morphology of cardiolipin domains in Escherichia coli membranes

Membrane domains characterized by unique protein and lipid composition allow for compartmentalization and regulation of various biological processes. In Escherichia coli cardiolipin domains play a key role in the dynamic organization of bacterial membranes, and their distribution depends on the stage of the cell cycle. We studied the influence of subinhibitory concentrations of ciprofloxacin and colistin on the morphology and distribution of E. coli cardiolipin domains. Using the fluorescent dye 10-N-nonyl acridine orange we found that exposure of bacteria to ciprofloxacin significantly increased the percentage of filamentous cells with altered morphology of the cardiolipin domains, while colistin did not induce any significant changes. These results allow us to conclude that inhibition of DNA gyrase causes effects even at the bacterial membrane level and those changes can be easily visualized using 10-N-nonyl acridine orange.

Mitochondrial protease AtFtsH4 protects ageing Arabidopsis rosettes against oxidative damage under short-day photoperiod

Mitochondrial atftsh4 protease, whose catalytic site is exposed to the intermembrane space, is one of four inner membrane-bound ftsh proteases in arabidopsis. we found that the loss of atftsh4 altered arabidopsis leaf morphology at the late stage of rosette growth under short-day photoperiod, while such changes were not observed in ftsh4 mutants grown under long days. these morphological changes were correlated with elevated levels of both reactive oxygen species (ros) and carbonylated proteins, which strongly suggested that ageing ftsh4 plants experienced oxidative stress. this view was supported by the accumulation of electron-dense material, presumably containing aggregated oxidized proteins, in mitochondria of ftsh4 plants with the most strongly malformed leaf blades. taken together, our data published in the may issue of plant journal suggest a link between the lack of AtFtsH4 protease, oxidative stress and altered leaf morphology at the late rosette stage under short days. Here, we present evidence that the onset of altered leaf morphology in ftsh4 correlates with an increase in the abundance of AtFtsH4 transcript observed in wildtype Arabidopsis growing under the same conditions. We also discuss how the lack of AtFtsH4 may cause oxidative stress towards the end of the vegetative growth in short days.

The lack of mitochondrial AtFtsH4 protease alters Arabidopsis leaf morphology at the late stage of rosette development under short-day photoperiod

AtFtsH4 is one of four inner membrane-bound mitochondrial ATP-dependent metalloproteases in Arabidopsis thaliana, called AAA proteases, whose catalytic site is exposed to the intermembrane space. In the present study, we used a reverse-genetic approach to investigate the physiological role of the AtFtsH4 protease. We found that loss of AtFtsH4 did not significantly affect Arabidopsis growth under optimal conditions (long days); however, severe morphological and developmental abnormalities in late rosette development occurred under short-day conditions. The asymmetric shape and irregular serration of expanding leaf blades were the most striking features of the ftsh4 mutant phenotype. The severe abnormal morphology of the leaf blades was accompanied by ultrastructural changes in mitochondria and chloroplasts. These abnormalities correlated with elevated levels of reactive oxygen species and carbonylated mitochondrial proteins. We found that two classes of molecular chaperones, Hsp70 and prohibitins, were over-expressed in ftsh4 mutants during late vegetative growth under both short- and long-day conditions. Taken together, our data indicate that lack of AtFtsH4 results in impairment of organelle development and Arabidopsis leaf morphology under short-day conditions.