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1.
Microorganisms ; 11(5)2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37317148

RESUMO

BACKGROUND: Amoebae of the genus Acanthamoeba cause a sight-threatening infection called Acanthamoeba keratitis. It is considered a rare disease in humans but poses an increasing threat to public health worldwide, including in Poland. We present successive isolates from serious keratitis preliminary examined in terms of the identification and monitoring of, among others, the in vitro dynamics of the detected strains. METHODS: Clinical and combined laboratory methods were applied; causative agents of the keratitis were identified at the cellular and molecular levels; isolates were cultivated in an axenic liquid medium and regularly monitored. RESULTS: In a phase-contrast microscope, Acanthamoeba sp. cysts and live trophozoites from corneal samples and in vitro cultures were assessed on the cellular level. Some isolates that were tested at the molecular level were found to correspond to A. mauritanensis, A. culbertsoni, A. castellanii, genotype T4. There was variability in the amoebic strain dynamics; high viability was expressed as trofozoites' long duration ability to intense multiply. CONCLUSIONS: Some strains from keratitis under diagnosis verification and dynamics assessment showed enough adaptive capability to grow in an axenic medium, allowing them to exhibit significant thermal tolerance. In vitro monitoring that was suitable for verifying in vivo examinations, in particular, was useful to detect the strong viability and pathogenic potential of successive Acanthamoeba strains with a long duration of high dynamics.

2.
Parasit Vectors ; 13(1): 624, 2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33353560

RESUMO

BACKGROUND: Free-living amoebae of the genus Acanthamoeba are cosmopolitan, widely distributed protozoans that cause a severe, vision-threatening corneal infection known as Acanthamoeba keratitis (AK). The majority of the increasing number of AK cases are associated with contact lens use. Appropriate eye hygiene and effective contact lens disinfection are crucial in the prevention of AK because of the lack of effective therapies against it. Currently available multipurpose contact lens disinfection systems are not fully effective against Acanthamoeba trophozoites and cysts. There is an urgent need to increase the disinfecting activity of these systems to prevent AK infections. Synthesized nanoparticles (NPs) have been recently studied and proposed as a new generation of anti-microbial agents. It is also known that some plant metabolites, including tannins, have anti-parasitic activity. The aim of this study was to evaluate the anti-amoebic activity and cytotoxicity of tannic acid-modified silver NPs (AgTANPs) conjugated with selected multipurpose contact lens solutions. METHODS: The anti-amoebic activities of pure contact lens care solutions, and NPs conjugated with contact lens care solutions, were examined in vitro by a colorimetric assay based on the oxido-reduction of alamarBlue. The cytotoxicity assays were performed using a fibroblast HS-5 (ATCC CRL-11882) cell line. The results were statistically analysed by ANOVA and Student-Newman-Keuls test using P < 0.05 as the level of statistical significance. RESULTS: We show that the NPs enhance the anti-Acanthamoeba activities of the tested contact lens solutions without increasing their cytotoxicity profiles. The activities are enhanced within the minimal disinfection time recommended by the manufacturers. CONCLUSIONS: The conjugation of the selected contact lens solutions with AgTANPs might be a novel and promising approach for the prevention of AK infections among contact lens users.


Assuntos
Ceratite por Acanthamoeba/prevenção & controle , Acanthamoeba castellanii/efeitos dos fármacos , Soluções para Lentes de Contato/farmacologia , Nanopartículas Metálicas/química , Prata/farmacologia , Taninos/farmacologia , Animais , Humanos
3.
Ann Agric Environ Med ; 26(2): 231-235, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31232051

RESUMO

INTRODUCTION AND OBJECTIVE: In recent decades the use of orthodontic appliances in Poland has increased; however, data on their influence on changes of components of the microbiome connected with oral biofilm are scarce. The objective of this study was to evaluate oral microbiota in terms of their role as risk factors for health complications. MATERIAL AND METHODS: The study included 100 patients treated with removable or fixed appliances. Oral hygiene and gingival health were determined, and periodontal swabs taken from each patient for parasitological, bacteriological and mycological microscopic and in vitro examinations. RESULTS: Oral protists and various pathogenic and opportunistic bacterial and fungal strains were identified in the superficial layer of biofilm. A higher prevalence of bacteria, Enterococcus faecalis, E. faecium, Staphylococcus aureus and Escherichia coli, and various strains of yeast-like fungi from the Candida albicans group, occurred in patients treated with the fixed appliance than in those using a removable appliance or not treated orthodontically. In some periodontal samples from patients treated with fixed appliances, cysts of the Acanthamoeba spp. were found. CONCLUSIONS: The use of orthodontic appliances alters the status of the oral cavity; it has impact on the colonization of oral biofilm by opportunistic/pathogenic strains, and increases the risk of their dissemination to various human tissues and organs. Pretreatment examination of oral microbiome, its monitoring particularly during treatment with fixed appliances, and preventive elimination of the potentially pathogenic strains to avoid health complications, are highly recommended, especially in patients with impaired immunity.


Assuntos
Biofilmes , Boca/microbiologia , Aparelhos Ortodônticos Fixos/microbiologia , Adolescente , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Fenômenos Fisiológicos Bacterianos , Criança , Feminino , Humanos , Masculino , Microbiota , Higiene Bucal , Polônia , Adulto Jovem
4.
Ann Parasitol ; 65(1): 19-25, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31095904

RESUMO

Acanthamoeba keratitis, the vision-threatening corneal disease reported with increasing frequency in Poland is difficult to treat due to extremely high resistance of the amoeba cysts to chemicals. The agents of possible anti-amoebic activity are still tested. Pathogenic Acanthamoeba samples/isolates acquired from severe cases of keratitis examined by molecular techniques to determine genotypes, compared to one another as well as to the environmental Acanthamoeba castellanii Neff strain were included in the studies. These strains were in vitro examined in terms of their sensitivity/resistance to selected chemicals and tolerance to temperature changes. Samples of the strains cultivated in vitro under bacteria-free conditions were monitored during different growth phases. Higher amoebic population dynamics was observed in both pathogenic Acanthamoeba strains during transfer to 37°C. Agents tested influenced population dynamics in different degree; they showed amoebostatic or amoebicidal effects, however a tendency toward induction of encystment also appeared. Because activation of the dormant cysts can lead to repeated development of amoebae, very important is cysticidal efficacy of chemicals. Further in vitro investigations on various Acanthamoeba strains with different chemicals are still necessary.


Assuntos
Acanthamoeba , Amebicidas , Temperatura , Acanthamoeba/efeitos dos fármacos , Acanthamoeba/genética , Ceratite por Acanthamoeba/parasitologia , Amebicidas/farmacologia , Genótipo , Humanos , Polônia , Saúde Pública
5.
Ann Agric Environ Med ; 26(1): 198-202, 2019 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-30922053

RESUMO

INTRODUCTION: Various Acanthamoeba species are free-living organisms widely distributed in the human environment. Amphizoic amoebae as facultative parasites may cause vision-threatening eye disease - Acanthamoeba keratitis, mostly among contact lens wearers. As the number of cases is increasing, and applied therapy often unsuccessful, proper hygienic measures and effective contact lenses disinfection are crucial for the prevention of this disease. Available contact lens solutions are not fully effective against amphizoic amoebae; there is a need to enhance their disinfecting activity to prevent amoebic infections. The use of developing nanotechnology methods already applied with success in the prevention, diagnostic and therapy of other infectious diseases might be helpful regarding amoebic keratitis. This study assesses the in vitro effect of selected contact lens solutions conjugated with nanoparticles against Acanthamoeba trophozoites. MATERIAL AND METHODS: Three selected contact lens solutions conjugated with silver and gold nanoparticles in concentration of 0.25-2.5 ppm were used in vitro against the axenically cultured ATCC 30010 type Acanthamoeba castellanii strain. The anti-amoebic efficacy was examined based on the oxido-reduction of AlamarBlue. The cytotoxicity tests based on the measurement of lactate dehydrogenase (LDH) activity were performed using a fibroblast HS-5 cell line. RESULTS: Enhancement of the anti-amoebic activity of contact lens solutions conjugated with selected nanoparticles expressed in the dose dependent amoebic growth inhibition with a low cytotoxicity profile was observed. CONCLUSIONS: Results of the study showed that conjugation of selected contact lens solutions with silver nanoparticles might be a promising approach to prevent Acanthamoeba keratitis among contact lens users.


Assuntos
Acanthamoeba castellanii/efeitos dos fármacos , Soluções para Lentes de Contato/farmacologia , Nanopartículas Metálicas/uso terapêutico , Ceratite por Acanthamoeba/prevenção & controle , Linhagem Celular Tumoral , Soluções para Lentes de Contato/toxicidade , Ouro/farmacologia , Ouro/toxicidade , Humanos , L-Lactato Desidrogenase/metabolismo , Nanopartículas Metálicas/toxicidade , Prata/farmacologia , Prata/toxicidade , Trofozoítos/efeitos dos fármacos
6.
Ann Agric Environ Med ; 25(4): 725-731, 2018 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-30586959

RESUMO

INTRODUCTION: Free-living amoebae, ubiquitous in outer environments, in predisposing circumstances may exist as parasites, infectious agents of Acanthamoeba keratitis. In recent decades, the vision-threatening corneal infection is a growing human health threat worldwide, including Poland. The applied therapy is often ineffective due to diagnostic mistakes, various pathogenicity of Acanthamoeba strains and high resistance of cysts to drugs; many agents with possible anti-amoebic activity are still being tested. In the presented study, selected chemicals are investigated in terms of their in vitro effect on corneal and environmental Acanthamoeba strains. MATERIAL AND METHODS: Samples of a corneal isolate from a patient with severe Acanthamoeba keratitis,of assessed on the basis of genotype associations of 18S rRNA and the type strain, Acanthamoeba castellanii Neff cultivated in bacteria-free condition, were exposed to povidone iodine, chlorhexidine digluconate or toyocamycin. In vitro population dynamics of the strains were monitored and compared to those of control cultures. RESULTS: All chemicals showed anti-amoebic effects with different degrees of effectiveness. Significant differences were observed in the in vitro population dynamics, and the morpho-physiological status of A. castellanii Neff T4 and corneal strains determined as A. polyphaga T4 genotype, exposed to povidone iodine or toyocamycin, in comparison with chlorhexidine taken as reference. CONCLUSIONS: Time-dependent amoebstatic in vitro effects were demonstrated for all agents, in particular, the results of assays with povidone iodine are promising. No significant stimulation of encystation appeared; however, as cysticidal efficacy of chemicals is expected, complementary research is needed on different Acanthamoeba strains with modified agent concentrations and method application.


Assuntos
Ceratite por Acanthamoeba/parasitologia , Acanthamoeba/efeitos dos fármacos , Antiprotozoários/farmacologia , Clorexidina/análogos & derivados , Povidona-Iodo/farmacologia , Toiocamicina/farmacologia , Acanthamoeba/classificação , Acanthamoeba/genética , Acanthamoeba/isolamento & purificação , Ceratite por Acanthamoeba/tratamento farmacológico , Ceratite por Acanthamoeba/epidemiologia , Clorexidina/farmacologia , Genótipo , Humanos , Polônia/epidemiologia
7.
Ann Parasitol ; 64(3): 229-233, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30316219

RESUMO

Small amoebae belonging to the Acanthamoeba genus complete their life cycles in different environmental niches as free-living protists however some of them are facultative parasites that can cause severe disease in humans. The sight-threatening Acanthamoeba keratitis develops in immune-competent persons, mainly in contact lens wearers; it is detected with increasing frequency along with the spread of contact lens use. The high abundance of the amoebae in the environment is important for dispersion and transmission of the infections among humans. Emerging threats for the public health generated by these amoebae is the serious medical problem worldwide. Nonspecific symptoms, similar to those occurring in the other eye diseases, diagnostic mistakes, the delay of an appropriate treatment, an exceptional high resistance of the amoebae to chemicals and drugs result in a prolonged course of the disease and often unsuccessful therapeutic management. Thus, different chemicals are still examined for their potential activity in vitro against various species, strains/isolates of Acanthamoeba. As the prolonged therapy often induces encystation subsequently leading to excystment and recurrences of amoebic keratitis, apart from anti-amoebic activity, cysticidal effect of examined agents is desirable. In the present study, results of our comparative investigations showed that cationic antiseptic chlorhexidine digluconate indicated in vitro anti-amoebic effect on environmental Acanthamoeba castellanii Neff strain and pathogenic corneal Acanthamoeba polyphaga T4 genotype. Amoebostatic effect of the disinfectant was expressed in reduced number of surviving amoebae in comparison to the respective control cultures; simultaneously, despite prolonged incubation with the agent no stimulation of encystation was noted. The corneal strain was more resistant to the tested compound than the Neff strain. The cysticidal efficacy of chemicals is very expected, thus further in vitro studies on pathogenic Acanthamoeba strains with different application chemicals pattern are needed.


Assuntos
Ceratite por Acanthamoeba , Acanthamoeba , Clorexidina , Desinfetantes , Acanthamoeba/efeitos dos fármacos , Ceratite por Acanthamoeba/tratamento farmacológico , Clorexidina/farmacologia , Doenças Transmissíveis Emergentes , Desinfetantes/farmacologia , Humanos , Polônia
8.
Ann Parasitol ; 64(4): 339-342, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30726664

RESUMO

In this study five cases of suspected alveolar echinococcosis from Poland in which surgical treatment was needed, previously diagnosed by means of imaging and serological techniques, were analyzed in terms to identify the causative agent. Samples of the parasite tissues taken perioperatively from the liver lesions were used for the histopathological and molecular examinations. The sequences of all isolates were identical to Echinococcus multilocularis; all nad1 sequences have been deposited in GenBank The histopathological examination revealed Passpositive fragments of laminated layers typical for E. multilocularis metacestode. Obtained results confirm that the use of imaging techniques only may be insufficient to diagnose alveococcosis thus the recognition of the zoonosis should base on several procedures; especially valuable are highly sensitive and specific molecular methods.


Assuntos
Equinococose , Echinococcus multilocularis , Animais , Equinococose/diagnóstico , Equinococose/parasitologia , Equinococose/cirurgia , Echinococcus multilocularis/anatomia & histologia , Echinococcus multilocularis/genética , Humanos , Fígado/parasitologia , Polônia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
9.
Ann Parasitol ; 63(3): 167-172, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29274209

RESUMO

Different Acanthamoeba species are amphizoic organisms distributed in wide range of habitats in natural and man-made environments; they are also detected on surfaces of equipment and accessories in health facilities. Some strains of the amoebae are causative agents of the vision-threatening human disease Acanthamoeba keratitis, mainly reported in contact lens wearers. An exceptional high resistance of Acanthamoeba trophozoites and particularly cysts to chemicals, disinfectants and drugs is believed as influencing difficulty resulting in unsuccessful therapeutic management. As Acanthamoeba keratitis is the serious medical problem worldwide, different chemicals with possible activity against environmental and clinical Acanthamoeba strains are tested. In our study, selected disinfectants used in health care settings and laboratories were tested and their efficacy against the corneal strains Acanthamoeba castellanii and A. polyphaga , and environmental A. castellanii Neff strain was assessed. Comparative assessment of results of the assays show that, apart from amoebistatic effects, the disinfectants indicated expected cysticidal efficacy.


Assuntos
Ceratite por Acanthamoeba/parasitologia , Acanthamoeba/efeitos dos fármacos , Amebicidas/farmacologia , Desinfetantes/farmacologia , Humanos
10.
Ann Parasitol ; 63(4): 341-346, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29420872

RESUMO

Amphizoic amoebae belonging to the genus Acanthamoeba are known as etiological agents of sight-threatening Acanthamoeba keratitis. The leading risk factor for the development of this serious human disease is contact lens wearing which popularity increases worldwide, also in Poland. The disease with active epithelial inflammations, corneal ulcers, including loss of the visual acuity is a serious medical problem as an emerging threat for the public health related to improper contact lens hygiene. The treatment of the amoebic keratitis is difficult, often unsuccessful due to delayed proper diagnosis. The clinical picture of the disease, often with severe course is nonspecific, similar to that occurring in viral, fungal or bacterial keratitis, thus clinical symptoms alone are not sufficient to identify the causative agent of the amoebic infection. Early diagnosis is decisive for the suitable therapeutic management and the treatment efficacy. In our studies, several complicated, difficult to treat Acanthamoeba keratitis incidences pertaining Polish patients using contact lenses have been retrospectively analyzed in terms of the usefulness of non-invasive methods of in vivo confocal microscopy and in vitro culture techniques applied for diagnosis. Hyper-reflective double-walled spherical Acanthamoeba cysts, with a more reflective outer wall were detected in the epithelium and anterior layers of the corneal stroma. In vivo confocal microscopy, if available, may be a valuable, sensitive tool for diagnosis in late identified severe infections mainly with strong viability strains, however confoscan may offer limited value at lowintensity amoebic infections. The microscopic visualization of amoebae in slides prepared directly from corneal scraping and laboratory examinations of specimens from in vitro cultivated corneal isolates allow to confirm or verify results of in vivo examinations, furthermore to identify directly the pathogens and to clarify previous misdiagnoses.


Assuntos
Ceratite por Acanthamoeba/patologia , Microscopia Confocal/métodos , Acanthamoeba , Ceratite por Acanthamoeba/diagnóstico , Ceratite por Acanthamoeba/parasitologia , Adulto , Lentes de Contato , Técnicas de Cultura , Feminino , Humanos , Masculino , Polônia/epidemiologia , Estudos Retrospectivos
11.
Ann Parasitol ; 62(3): 233-237, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27770763

RESUMO

In this research, a comparative analysis of results of investigations involving different human populations, in terms of a relation between the oral cavity health and the species composition of mouth microbiota is reported. The purpose of this analysis was to identify and assess microorganisms that could cause health complications in patients with neoplasm requiring dental problem-related surgical management. The patients with the oral cancer surgically treated and those without neoplasm were assessed for their oral health: status of teeth, gingiva, periodontium, and occurrence of inflammatory processes. From each patient, microorganisms isolated of periodontium, dental plaque, and dental pocket swabs were identified in wet and stained microscopic preparations; standard microbiology in vitro techniques were also applied to determine the fungal and bacterial strains. The comparative analysis of results of direct microscopic examinations and in vitro cultures assessment indicated significant differences in prevalences of fungi, parasitic oral protozoans and bacteriae in particular patient's groups. Yeast-like fungi belonging to Candida genus, mostly of C. albicans group, were identified in 93.75% patients with the oral cancer, while in 25% of individuals assessed without neoplasm. E. gingivalis amoebae were only found in 12.5% patients with the serious disease; no trichomonads were detected in all patients analyzed. Among bacteria species, potentially pathogenic Enterobacteriaceae were found in the patients with oral cancer. The pronounced shift in the microbiota species composition in the patients who needed prolonged treatment due to oral cavity cancer, compared to other generally healthy persons has been showed in this analysis.


Assuntos
Bactérias/isolamento & purificação , Candida albicans/isolamento & purificação , Entamoeba/isolamento & purificação , Boca/microbiologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças da Boca/cirurgia
12.
Ann Parasitol ; 62(1): 71-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27262961

RESUMO

The retrospective analysis of data on oral cavity clinical status in relation to microbiota species composition is presented. The research regards patients of different age, with and without congenital malformation, pretreatment assessed for occurrence of pathological changes in the masticatory system. Samples of the swabs collected from each patient (from dental plaque, periodontium and dental pockets) were used for identification of oral protozoans in wet slides and stained preparations; additionally, transmission electron microscope examination was performed. The material was used for in vitro cultures to identify bacteria strains. Clinically, intensity of tissue deteriorations was higher in patients with a congenital disease. Alive Trichomonas tenax and Entamoeba gingivalis, species with confirmed pathogenic impact on oral cavity and neighboring structures, were detected with higher prevalence in older patients. Enterococci, Staphylococcus aureus, various Enterobacteriaceae were more frequently detected in patients with somatic and mental retardations; in mouths of those patients, Klebsiella pneumonia and Pseudomonas aeruginosa opportunistic strains occurred. Masticatory system abnormalities favor colonization of oral cavity by exogenous species and dissemination of infections, especially dangerous for patients with congenital diseases. Oral microbiota assessment and preventive measures may be helpful to avoid subsequent peri-surgery complications.


Assuntos
Infecções Bacterianas/microbiologia , Doenças da Boca/microbiologia , Doenças da Boca/parasitologia , Infecções por Protozoários/parasitologia , Adulto , Animais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por Protozoários/epidemiologia
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