Non-thermal plasma disinfecting procedure is harmless to delicate items of everyday use.

Non-thermal plasma (NTP) is a well-known decontamination tool applicable for a wide range of microorganisms and viruses. Since the recent COVID-19 pandemic highlighted the need to decontaminate all daily used items, it is highly desirable to address the applicability of NTP, including its possible harmful effects. To the best of our knowledge, a comprehensive characterization of NTP effects on sensitive materials is still lacking. We investigated the potential damage to common materials of daily use inflicted by air atmospheric NTP generated in Plasmatico v1.0. The materials tested were paper, various metals, and passive and active electronic components modelling sensitive parts of commonly used small electronic devices. The NTP-exposed paper remained fully usable with only slight changes in its properties, such as whitening, pH change, and degree of polymerization. NTP caused mild oxidation of copper, tinned copper, brass, and a very mild oxidation of stainless steel. However, these changes do not affect the normal functionality of these materials. No significant changes were observed for passive electronic components; active components displayed a very slight shift of the measured values observed for the humidity sensor. In conclusion, NTP can be considered a gentle tool suitable for decontamination of various sensitive materials.

Addition time plays a major role in the inhibitory effect of chitosan on the production of Pseudomonas aeruginosa virulence factors.

Pseudomonas aeruginosa is a gram-negative bacterium capable of forming persistent biofilms that are extremely difficult to eradicate. The species is most infamously known due to complications in cystic fibrosis patients. The high mortality of cystic fibrosis is caused by P. aeruginosa biofilms occurring in pathologically overly mucous lungs, which are the major cause facilitating the organ failure. Due to Pseudomonas biofilm-associated infections, remarkably high doses of antibiotics must be administered, eventually contributing to the development of antibiotic resistance. Nowadays, multidrug resistant P. aeruginosa is one of the most terrible threats in medicine, and the search for novel antimicrobial drugs is of the utmost importance. We have studied the effect of low molecular weight chitosan (LMWCH) on various stages of P. aeruginosa ATCC 10145 biofilm formation and eradication, as well as on production of other virulence factors. LMWCH is a well-known naturally occurring agent with a vast antimicrobial spectrum, which has already found application in various fields of medicine and industry. LMWCH at a concentration of 40 mg/L was able to completely prevent biofilm formation. At a concentration of 60 mg/L, this agent was capable to eradicate already formed biofilm in most studied times of addition (2-12 h of cultivation). LMWCH (50 mg/L) was also able to suppress pyocyanin production when added 2 and 4 h after cultivation. The treatment resulted in reduced formation of cell clusters. LMWCH was proved to be an effective antibiofilm agent worth further clinical research with the potential to become a novel drug for the treatment of P. aeruginosa infections.

[The possibility of using the results of the study of oral fluid and buccal epithelium in the diagnosis of Alzheimer's disease.]

The article presents the results of the first experience of comparative studies of the state of the oral fluid and buccal epithelium in 12 patients suffering from Alzheimer's disease, and in 12 individuals without any signs of cognitive impairment. In the course of the study, the correlative relationships of pro-inflammatory and anti-inflammatory factors of the oral fluid, the main cytological changes of the buccal epithelium with the results obtained during neuropsychological testing using the MMSE and ADAS-COG scales were studied. This comparative study is associated with the assumption of a common ectodermal origin of the nervous tissue and buccal epithelium, which may be due to systemic pathological changes in the tissues of a single embryonic embryo leaf. The results obtained indicate the specificity of pathological changes in the oral fluid and buccal epithelium for Alzheimer's disease, which allows us to use the study of these materials to obtain additional diagnostic markers of this disease.

Antibiofilm agent pterostilbene is able to enhance antibiotics action against Staphylococcus epidermidis.

Pterostilbene (PTE) is a naturally occurring compound originally isolated from Pterocarpus spp. It has been widely used in traditional Indian medicine and later discovered to have various beneficial pharmacological effects such as antioxidant properties, hypoglycaemic or antitumor, and antimicrobial activity. This work is focused on demonstrating PTE synergistic effect with erythromycin and tetracycline to reduce their needed effective concentration for suppression of Staphylococcus epidermidis planktonic cells growth and biofilm formation. The secondary aim is to find these combinations effect on the production of its virulence factors. PTE was found to be effective in inhibition of its planktonic cells with MIC80 values 25-37.5 mg l-1. Simultaneously, it decreased the metabolic activity of biofilm cells and was especially effective on a clinical isolate (MBIC80 = 35 mg l-1) in contrast to the conventional antibiotics. In combination, PTE helped the antibiotics to overcome the tolerance of S. epidermidis biofilm cells (5 mg l-1 of each antibiotic with 49 mg l-1 PTE caused more than 85% inhibition of metabolic activity). It permeabilized cytoplasmic membrane of S. epidermidis cells and altered their surface hydrophobicity. Therefore, PTE has a great potential to enhance antibiotics action in the treatment of infections caused by this pathogen.

Natural antioxidant pterostilbene as an effective antibiofilm agent, particularly for gram-positive cocci.

Pterostilbene (PTE), a dimethylated analogue of resveratrol, mostly contained in Vitis vinifera leaves or in other plant sources is well-known for its antioxidant activity. Due to its bioavailability, low hydrophilicity and thus ability to penetrate hydrophobic biological membranes it was found to be an antimicrobial agent. These properties of PTE offer the possibility of its use in the treatment of microbial infections. The emergence of antibiotic resistance of microorganisms is often caused by their ability to form biofilm; new substances with antibiofilm activity are therefore sought. The representatives of opportunistic pathogenic gram-positive and gram-negative bacteria as well as fungi were used for the determination of minimum inhibitory concentrations (MIC50 and MIC80), minimum biofilm inhibitory concentrations (MBIC50 and MBIC80) and minimum biofilm eradication concentrations (MBEC50 and MBEC80) of PTE and commonly used antibiotics erythromycin, polymyxin B or antimycotic amphotericin B. Total biofilm biomass was investigated by crystal violet staining, and the results were confirmed using microscopic techniques. The most significant antibiofilm action was proved for gram-positive cocci, e.g., MBEC50 of PTE for all strains of Staphylococcus epidermidis tested was 25 mg/L. By contrast, the antibiotic ERM did not exhibit antibiofilm activity in most cases. The permeabilization of cell membranes of gram-positive cocci biofilm by MBIC50 and MBEC50 of PTE was confirmed by LIVE/DEAD staining using spinning disc confocal microscopy. PTE significantly influenced the ability of gram-positive cocci to form biofilm and it effectively eradicated pre-formed biofilm in vitro; its potential for the treatment of biofilm-associated infections of Staphylococcus spp. or Enterococcus faecalis is thus apparent.

[Tumors in children with birth defects. Current data from the Czech Republic]. / Nádorová onemocnení u detí narozených s vrozenou vadou aktuální data v Ceské republice.

AIM OF STUDY: An analysis of birth defects incidences in a co-incidence with children age tumors in the Czech Republic in 1994 - 2005. Some bio-social factors (maternal age, birth weight, gestational week at birth) and their roles were studied as well. TYPE OF STUDY: Retrospective demografic-epidemiological analysis of birth defects and children age tumors incidences in children born in the Czech Republic during 1994 - 2005. MATERIAL AND METHODS: Data from the National Birth Defects Register and National Oncological Register (both run in the Institute for Health Information and Statistics) in the Czech Republic were used along with some additional data from the Register of newborns and Register of mothers at childbirth. Out of these data, a group of children with both birth defect and tumor was analyzed according to particular diagnoses and to some selected bio-social factors. Out of the total number 1707 children with tumor (934 (54.7%) boys and 773 (45.3%) girls) were 1572 children without birth defect and 135 with both tumor and birth defect. Total number of children with birth defect were 39 197 (39 059 live births and 138 stillbirths), 22 741 (58.1%) boys and 16 435 (41.9%) girls (in 21 cases the sex was not specified). In these children totally 53 539 birth defect diagnoses were registered (30 739 in boys, 22 781 in girls and 19 in children with unspecified sex). RESULTS: In 1572 children without birth defect and with tumor, a mean age at time of tumor diagnosis was 3.6 years, in 135 children with both tumor and birth defect was 2.2 years, which is significantly lower (p < 0.001, Mann-Whitney U test). No statistically significant difference was found in birthweight and birthlenght and gestational week and maternal age at time of delivery. An increased frequency of tumors in the group of children with birth defect was found in groups mesothelial tumors (C45 - C49), tumors of urinary tract (C64 - C68) and tumors of head and neck (C00 - C14, C30 - C31). On the other hand, a decreased tumor frequency in the group of children with birth defect was found in groups of lymfoid and haematopoietic tumors ((C81 - C96) and tumors of eye and brain (C69 - C72). As a risk factor of tumorigenesis in in children with birth defect was a birth defect from groups of defects of cardiovascular system, uropoietic system, chromosal aberrations and other unspecified defects. In children with both birth defect and tumor a decreased survival rate (p = 0.0437, Log-rank test) was found. A decreased survival rate was also confirmed after tumor diagnosis, although this decrease was not statistically significant (p = 0.2021, Log-rank test). There is also a highly statistically significant difference (p < 0.001, Log-rank test) in survival between groups with and without a birth defect prior to tumor diagnosis. CONCLUSIONS: A higher risk of tumorigenesis in children with birth defect (compared to children without birth defect) was confirmed. There was also a lower survival in a group of children with tumor and birth defect compared to those with tumor and without birth defects. A higher risk of tumorigenesis in some types of birt defects was also found.