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Temperature responsivity of polymer brushes may be driven by different mechanisms, from which the lower critical solution temperature (LCST) is the most famous one. The using of the grafted temperature-responsive polymer brushes based on LCST opens numerous opportunities for fabrication of “smart” or responsive surfaces. In this review, we try to join information on thermoresponsive and multi-responsive grafted polymer brushes with transitions based on LCST. The overwhelming majority of previously reported temperature-responsive grafted polymer brush coatings were based on PNIPAM and POEGMA, despite the fact that a wide range of other thermoresponsive polymers demonstrate similar properties. In this work, we not only give the detailed account for fabrication, mechanisms of action, and applications of well-known PNIPAM- and POEGMA-grafted brush coatings but also point to other types of thermoresponsive grafted brushes.

New temperature-responsive hybrid nanomaterials based on modified halloysite nanotubes (HNTs) containing grafted polymer brushes with silver nanoparticles have been successfully fabricated. We used a three steps process including synthesis of the initiating coatings onto HNTs surface, fabrication of the POEGMA – poly(oligo(ethylene glycol)ethyl ether methacrylate) grafted brushes and synthesis of the silver nanoparticles (AgNPs). The synthesis and properties of hybrid nanomaterials were studied by FT-IR, TGA and DLS methods. It is shown that the introduction of AgNPs, formed from 0.005 M AgNO3 solution leads to a significant reduction of low critical solution temperature (LCST) of the polymer layer from 29.7 to 21.6 °C. The samples fabricated from 0.05 M AgNO3 solution did not evidence a temperature-induced transition, despite of the contents of AgNPs obtained for both solutions are almost identical (≈ 4%w). The presence of AgNPs with sizes of ca. 20 nm was confirmed in the hybrids prepared from both AgNO3 concentrations by UV–vis spectroscopy, and electron microscopy. These temperature-responsive hybrid nanomaterials may be used for conservation of solid substrates, production of advanced medical facemasks, photothermal therapy against microorganisms and tumors etc.

Introduction: Vestibular schwannoma (VS) is known to be a benign tumor. It develops from the Schwann cells in the vestibular portion of the VIII nerve. The causes of tumor development are not fully defined. VS is diagnosed more often in people of active age (30-60 years), mostly in women. Aim: The aim is to study the state of vestibular and acoustic dysfunctions in patients with VS at an early stage. Materials and Methods: A total of 71 patients with MRI-verified VS at an early stage were analyzed. The 1st group consisted of 34 patients with intracanal VS, and the 2nd group included 37 patients with stage one VS. Vestibular dysfunction, including the registration of three pathological vestibular reactions vestibulo-somatic, vestibulo-sensory and vestibulo-vegetative, was studied. Acoustic dysfunction was studied using tonal, speech and suprathreshold speech audiometry, and auditory brainstem responses (ABR). Results: Unilateral or asymmetric bilateral vestibular dysfunctions have been established in all patients at the early stages of VS, which forms phantom phenomena of sensory and motor memory in the cortical structures of the brain in the form of pathological vestibulo-somatic, vestibulo-sensory and vestibulo-vegetative reactions, which are to be considered during rehabilitation. Acoustic dysfunction of different manifestations—from normal symmetrical hearing to socially adequate unilateral or asymmetric sensorineural hearing loss of degree I-II, and significant socially inadequate sensorineural hearing loss of degree III-IV, deafness, and also mixed hearing loss, was determined in these patients. ABR registration indicated unilateral or asymmetric delays of sound signals transferring in the brainstem structures at the early stages of VS with both normal hearing and socially adequately impaired hearing. Conclusion: Various manifestations of vestibular and acoustic dysfunctions with development of excitatory and inhibitory processes in the peripheral, brainstem, and cortical structures of the vestibular and acoustic systems were defined in all patients at the early stages of VS.

Bacteria, their endotoxin and mold found on pollen can be a reason of respiratory symptoms in sensitized individuals. This question concerns an anemophilous pollen more acute. In this work quantitative by dilution plating method and qualitative microbial analysis by MALDI-TOF MS Biotyper of pollen and other plants organs of Pinus sylvestris L., P. nigra Arnold, P. mugo Turra, P. armandii Franch., P. wallichiana A.B. Jacks from Nitra, Slovakia are performed which shows quantitative and species differences in mesophilic aerobic (0.00-6.27 log cfu/g) and anaerobic bacteria (0.00-3.70 log cfu/g), enterococci (0.00 log cfu/g), coliform bacteria (0.00-5.29 log cfu/g), lactobacilli (0.00-4.20 log cfu/g), microscopic fungi and yeasts (2.60-5.29 log cfu/g) content. Representatives of Pseudomonas (14), Bacillus (2), Acinetobacter (1), Arthrobacter (1), Pantoea (1), Klebsiella (1), Penicillium (6), Aspergillus (4), Cladosporium (1), Debaryomyces (1) genera were revealed on pine trees. The allergenic potential of the identified association of microorganisms on pollen has been evaluated based on published data. The results may be useful for aerobiologists, allergists and microbiologists, at least at the local level.

Quantitative microbiological analysis by dilution plating method of pollen and additional male and female catkins, leaves of Betula verrucosa Ehrh. and its two cultivars: ‘Purpurea’ and ‘Youngii’ relatively of flowering period of Betula has been realized with the aim to provide new knowledge of the microbiological quality of anemophilous pollen for processing and its further application. Qualitative microbiological analysis with MALDI-TOF MS Biotyper was used in the identification of aerobic, anaerobic mesophilic bacteria and coliforms. Mixed microbiota was determined, consisting of aerobic (4.68–4.89 log cfu/g) and anaerobic (3.30–3.48 log cfu/g) mesophilic bacteria, lactobacilli (0–3.48 log cfu/g), coliform bacteria (0–4.57 log cfu/g), fungi and yeast (3.78–3.95 log cfu/g) on the pollen grains, that indicates acceptable quality in comparison with the microbiological quality parameters for bee pollen. Pantoea agglomerans was found associated with pollen of Betula verrucosa Ehrh. Recommendations on the collection of anemophilous pollen were established.

The aim of this study is to determine and compare microbiological contamination of anemophilous pollens (Betula verrucosa Ehrh., Betula verrucosa Ehrh. 'Youngii', Pinus sylvestris L., Pinus nigra Arnold, Pinus mugo Turra, Pinus armandii Franch., Pinus wallichiana A.B. Jacks) after collection and after not long-term storage. Samples were picked by hands aseptically in the territory of the same environmental conditions in Slovakia. Colonies of mesophilic aerobic and anaerobic bacteria, lactobacilli, total coliforms, fungi and yeast were found on pollen samples by dilution plating method. It was found significant differences in content of lactobacilli for birch pollens and fungi and yeast on pine pollens, depending on the stages – collection and storage. The microbiological quality of Betula pollen is better than Pinus pollen after collection and storage. Species factor affects the microbiota of anemophilous pollen.

The aim of this study was to detect the antimicrobial activity of four plant pollen samples to pathogenic bacteria, microscopic fungi and yeasts. Pollens of dogwood common (Cornus mas), ray mountain (Secale strictum spp. strictum), pumpkin rape (Cucurbita pepo var. styriaca) and grape vine (Vitis vinifera) were collected in 2010 in Slovakia. The antimicrobial effects of the four nontraditional plant pollens were tested using the agar well diffusion method. For extraction, 70% ethanol (aqueous, v/v) was applied. Antimicrobial susceptibility of five different strains of bacteria - three gram positive (Listeria monocytogenes CCM 4699, Pseudomonas aeruginosa CCM 1960, Staphylococcus aureus CCM 3953) and gram negative (Salmonella enterica CCM 4420, Escherichia coli CCM 3988), as well as three different strains of microscopic fungi, Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, and three different strains of yeasts Candida albicans, Geotrichum candidum and Rhodotorula mucilaginosa, were examinated. L. monocytogenes was the most sensitive among bacteria to the three ethanol extracts of plant pollen after 24 hours of inoculation, A. flavus and C. albicans were the most sensitive microscopic fungi and yeast species, respectively.