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1.
Artigo em Inglês | MEDLINE | ID: mdl-39148402

RESUMO

INTRODUCTION: Congenital hypofibrinogenemia (CH) and congenital dysfibrinogenemia (CD) are rare coagulation disorders caused by quantitative or qualitative defects in the fibrinogen gene. The aim of this study was to characterize the genetic background and the clinical manifestations of congenital fibrinogen disorders in the patients from Slovakia registered at the National Haemophilia Centre. MATERIALS AND METHODS: Results of genetic analysis of the fibrinogen genes FGA, FGB and FGG using polymerase chain reaction followed by direct sequencing were evaluated in 36 patients. RESULTS: Molecular-genetic analysis revealed six novel variants - FGA c.923_968dup p.(Gly324Lysfs*44) and FGG c.1105C>T p.(His369Tyr) were identified in CD patients. In CH patients, in the FGG gene c.8G>A p.(Trp3*), c.823G>T p.(Glu275*) and c.323C>A p.(Ala108Asp) variants were detected. In the FGB gene c.1427C>T p.(Ser476Leu) was identified. CONCLUSION: This study is a positive contribution towards expanding knowledge about genetic variants in patients with congenital fibrinogen disorders.

2.
Langmuir ; 39(20): 7046-7056, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37162149

RESUMO

A simple noninvasive measurement method which allows one to determine the trapped charge in a biocompatible hydroxyapatite dielectric is developed. The hydroxyapatite samples are charged by electron beam with energy 30 keV and total irradiated charge ranging from 2 × 10-9 C to 2 × 10-7 C. The value of the trapped charge is determined by analyzing the shape change of a liquid droplet hanging from a needle in proximity of the charged sample surface. The shape change of the pendant drop in the field of gravity is commonly utilized in the measurements of the surface free tension (SFT) of liquids. The external electric field leads to a further modification of the droplet shape and to an effective change of the SFT. The change of the SFT as a function of distance between the droplet and sample and the critical distance at which the droplet detaches from the needle are measured for various values of the irradiated charge. These two quantities are also derived theoretically by considering the trapped charge as a single fitting parameter. We can thus determine the trapped charge in two independent noninvasive ways. It is noteworthy that our method is easily implementable into the standard pendant drop setups. As a practical application of the method, a long-term charge stability of the charged hydroxyapatite is demonstrated, thus paving the way toward quantitative studies of its bioactivity in dependence on the value of the trapped charge.

3.
Appl Microbiol Biotechnol ; 106(5-6): 2107-2119, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35194655

RESUMO

Non-thermal plasma (NTP) represents the fourth state of matter composed of neutral molecules, atoms, ions, radicals, and electrons. It has been used by various industries for several decades, but only recently NTPs have emerged in fields such as medicine, agriculture, and the food industry. In this work, we studied the effect of NTP exposure on aflatoxin production, conidial germination and mycelial vitality, morphological and surface changes of conidia and mycelium. When compared with colonies grown from untreated conidia, the colonies from NTP-treated conidia produced significantly higher levels of aflatoxins much earlier during development than colonies from untreated conidia. However, at the end of cultivation, both types of cultures yielded similar aflatoxin concentrations. The increase in the accumulation of aflatoxins was supported by high transcription levels of aflatoxin biosynthetic genes, which indicated a possibility that NTP treatment of conidia was having a longer-lasting effect on colony development and aflatoxins accumulation. NTP generated in the air at atmospheric pressure effectively devitalized Aspergillus parasiticus in conidia and hyphae within a few minutes of treatment. To describe devitalization kinetics, we applied Weibull and Hill models on sets of data collected at different exposure times during NTP treatment. The damage caused by NTP to hyphal cell wall structures was displayed by raptures visualized by scanning electron microscopy. Fourier transform infrared spectroscopy demonstrated that changes in cell envelope correlated with shifts in characteristic chemical bonds indicating dehydration, oxidation of lipids, proteins, and polysaccharides. Key points • Non-thermal plasma increases aflatoxin production shortly after treatment. • Non-thermal plasma rapidly devitalizes Aspergillus parasiticus. • Non-thermal plasma disrupts the cell surface and oxidizes biological components.


Assuntos
Aflatoxinas , Gases em Plasma , Aspergillus/genética , Gases em Plasma/farmacologia , Esporos Fúngicos
4.
Antonie Van Leeuwenhoek ; 113(10): 1479-1488, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32766937

RESUMO

Aspergillus ochraceus is a soil fungus known to produce ochratoxin A, a harmful secondary metabolite. Prevention and control of fungal pathogens mostly rely on chemical fungicides, which is one of the contributing factors in the emergence of the fungal resistance, hence novel methods for fungal eradication have been extensively researched. The cold atmospheric pressure (CAP) plasma generated in ambient air has been recently applied in microbial decontamination. Here we used the diffuse coplanar surface barrier discharge in inactivation of a toxigenic strain A. ochraceus. The plasma-treated conidia and mycelium exhibited morphological changes such as ruptures and desiccation. Mycelium dehydration and changes in the chemical composition of hyphal surface accompanied plasma treatment. The growth of 26 h old mycelia were significantly restricted after 30 s of plasma treatment. The conidial vitality declined 4 logs after 180 s of plasma exposure leading to almost complete decontamination. After shorter plasma treatment of conidia, the ochratoxin A (OTA) production increased at the early stage of cultivation, but the overall level was significantly reduced compared to untreated samples after longer cultivation. Our results indicated that the fungal growth and the OTA production were significantly changed by plasma treatment and underscored CAP plasma as a promising method in the decontamination of A. ochraceus without a risk to generate strains with increased OTA production.


Assuntos
Aspergillus ochraceus/efeitos dos fármacos , Aspergillus ochraceus/metabolismo , Ocratoxinas/biossíntese , Gases em Plasma/farmacologia , Aspergillus ochraceus/crescimento & desenvolvimento , Aspergillus ochraceus/ultraestrutura , Relação Dose-Resposta a Droga , Viabilidade Microbiana/efeitos dos fármacos , Micélio/efeitos dos fármacos , Esporos Fúngicos/efeitos dos fármacos
5.
Neurocase ; 24(4): 227-230, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30376408

RESUMO

Phelan-McDermid syndrome (PMD) is a rare genetic condition with only a few cases describing patients diagnosed as adults. We describe a long diagnostic odyssey of a 30-year-old woman who was diagnosed with Phelan-McDermid syndrom. Array comparative genomic hybridization analysis confirmed a 22q13.33 deletion, encompassing exon 9-23 of the SHANK3 gene and exon 1 of the ACR gene. We provide an uncommon feature of the disease, where psychotic alteration is repeatedly triggered by the same physical factor in our patient - mild fever episodes.


Assuntos
Transtorno Bipolar/etiologia , Transtornos Cromossômicos/complicações , Febre/complicações , Adulto , Deleção Cromossômica , Transtornos Cromossômicos/psicologia , Cromossomos Humanos Par 22 , Feminino , Humanos
6.
Appl Microbiol Biotechnol ; 102(15): 6647-6658, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29858953

RESUMO

The cold atmospheric-pressure plasma (CAPP) has become one of the recent effective decontamination technologies, but CAPP interactions with biological material remain the subject of many studies. The CAPP generates numerous types of particles and radiations that synergistically affect cells and tissues differently depending on their structure. In this study, we investigated the effect of CAPP generated by diffuse coplanar surface barrier discharge on hyphae of Aspergillus flavus. Hyphae underwent massive structural changes after plasma treatment. Scanning electron microscopy showed drying hyphae that were forming creases on the hyphal surface. ATR-FTIR analysis demonstrated an increase of signal intensity for C=O and C-O stretching vibrations indicating chemical changes in molecular structures located on hyphal surface. The increase in membrane permeability was detected by the fluorescent dye, propidium iodide. Biomass dry weight determination and increase in permeability indicated leakage of cell content and subsequent death. Disintegration of nuclei and DNA degradation confirmed cell death after plasma treatment. Damage of plasma membrane was related to lipoperoxidation that was determined by higher levels of thiobarbituric acid reactive species after plasma treatment. The CAPP treatment led to rise of intracellular ROS levels detected by fluorescent microscopy using 2',7'-dichlorodihydrofluorescein diacetate. At the same time, antioxidant enzyme activities increased, and level of reduced glutathione decreased. The results in this study indicated that the CAPP treatment in A. flavus targeted both cell surface structures, cell wall, and plasma membrane, inflicting injury on hyphal cells which led to subsequent oxidative stress and finally cell death at higher CAPP doses.


Assuntos
Aspergillus flavus/efeitos dos fármacos , Descontaminação , Viabilidade Microbiana/efeitos dos fármacos , Gases em Plasma/farmacologia , Antioxidantes/metabolismo , Aspergillus flavus/enzimologia , Hifas/efeitos dos fármacos
7.
Food Res Int ; 106: 862-869, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29579997

RESUMO

In present study, the inhibition effect of low temperature plasma on Bacillus subtilis, Escherichia coli, Salmonella Enteritidis and B. subtilis endospores inoculated on the surface of black peppercorns was studied. Plasma was generated by Diffuse Coplanar Surface Barrier Discharge (DCSBD) at atmospheric pressure in ambient air. Plasma treatment time of 300 s led to log10 CFU/g reduction of B. subtilis from 7.36 to 2.30 and B. subtilis endospores from 4.42 to 2.39. Plasma treatment reduced the number of E. coli and Salmonella Enteritidis to below detection level (1.0 log10 CFU/g) from initial populations of 7.45 log10 CFU/g and 7.60 log10 CFU/g, respectively. The inactivation kinetics was explained by Weibull model. Decimal reduction times (D-values) for B. subtilis, E. coli, Salmonella Enteritidis, and B. subtilis endospores were determined as 43 s, 47 s, 58 s, and 142 s, respectively. The surface morphology observed by Scanning Electron Microscopy showed no significant changes after the plasma treatment. The influence of plasma on chemical bonds on the surface and inside the peppercorns was studied by Attenuated Total Reflectance - Fourier Transform Infrared Spectroscopy.


Assuntos
Microbiologia de Alimentos , Piper nigrum/microbiologia , Gases em Plasma , Bacillus subtilis/crescimento & desenvolvimento , Bacillus subtilis/isolamento & purificação , Contagem de Colônia Microbiana , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/isolamento & purificação , Contaminação de Alimentos , Conservação de Alimentos , Salmonella enteritidis/crescimento & desenvolvimento , Salmonella enteritidis/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier , Esporos Bacterianos/crescimento & desenvolvimento , Esporos Bacterianos/isolamento & purificação
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