Evidence of adaptation, niche separation and microevolution within the genus Polaromonas on Arctic and Antarctic glacial surfaces.

Polaromonas is one of the most abundant genera found on glacier surfaces, yet its ecology remains poorly described. Investigations made to date point towards a uniform distribution of Polaromonas phylotypes across the globe. We compared 43 Polaromonas isolates obtained from surfaces of Arctic and Antarctic glaciers to address this issue. 16S rRNA gene sequences, intergenic transcribed spacers (ITS) and metabolic fingerprinting showed great differences between hemispheres but also between neighboring glaciers. Phylogenetic distance between Arctic and Antarctic isolates indicated separate species. The Arctic group clustered similarly, when constructing dendrograms based on 16S rRNA gene and ITS sequences, as well as metabolic traits. The Antarctic strains, although almost identical considering 16S rRNA genes, diverged into 2 groups based on the ITS sequences and metabolic traits, suggesting recent niche separation. Certain phenotypic traits pointed towards cell adaptation to specific conditions on a particular glacier, like varying pH levels. Collected data suggest, that seeding of glacial surfaces with Polaromonas cells transported by various means, is of greater efficiency on local than global scales. Selection mechanisms present of glacial surfaces reduce the deposited Polaromonas diversity, causing subsequent adaptation to prevailing environmental conditions. Furthermore, interactions with other supraglacial microbiota, like algae cells may drive postselectional niche separation and microevolution within the Polaromonas genus.

[Supplementation with omega fatty acids in various diseases]. / Suplementacja kwasami omega w róznych chorobach.

For some decades, an increase in propagation of coronary heart disease, obesity, diabetes, tumors and mental disorders has been observed. Consequently, new and effective methods of treatment of these diseases using drugs and diet supplements have been developed. A promising solution is the use of polyunsaturated fatty acids in the treatment of some diseases. These compounds have broad application in prevention of many diseases and are used to support standard therapies. Their activity is connected with participation in metabolic processes regulating biochemical transformations in cells and tissues. Omega-3 fatty acids regulate production of cytokines, increased levels of which may contribute to occurrence of chronic inflammatory diseases, autoaggression of the immunological system, arteriosclerosis or tumor development. These substances exert a beneficial effect on the blood system by improvement of blood circulation and nerve signal transmission. Omega-3 fatty acids reduce the risk of irregular heartbeat, stabilize arterial pressure, and restore balance in cholesterol metabolism disorders. They also play a key role in maintaining physical and mental efficiency; thus administration of these compounds for young children is of great importance. Nevertheless, administration of omega-3 fatty acids in the diet seems to be essential. The purpose of this study is to present the structure and sources of omega-3 and - 6 fatty acids and discuss the problems concerning therapeutic use of these compounds in various disorders.

Indocyanine green angiography in chronic central serous chorioretinopathy.

BACKGROUND: Central serous chorioretinopathy (CSC) is a condition that originates from alterations of the choroidal circulation. The aim of this paper was to evaluate the use of indocyanine green angiography (ICGA) in patients with chronic CSC. MATERIAL/METHODS: The analysis included 17 patients (34 eyes) with chronic CSC in at least 1 eye. The eye examination included: distance and near visual acuity, biomicroscopy, applanation tonometry, fundus examination, colored and red-free fundus photography, evaluation of autofluorescence, optical coherence tomography, and fluorescein and indocyanine green angiography. RESULTS: In 34 eyes (100%) involved in the ICGA study the results revealed zones of transient increased choroidal vessels permeability. In 18 eyes (52.9%) choroidal changes were accompanied by a focal serous pigment epithelial detachment. In 4 eyes (11.8%) of 3 patients' the ICGA examination confirmed the presence of occult choroidal neovascularization (CNV). In the patient with bilateral diffuse retinal pigment epitheliopathy, CNV was present in 1 eye, in the patient with unilateral chronic CSC it was also present in 1 eye, and in the third patient with bilateral chronic CSC it was detected in both eyes. CONCLUSIONS: ICGA is a very useful examination that enables ophthalmologists to visualize choroidal changes due to chronic CSC, as well as to diagnose occult CNV in chronic CSC.

The C2H2 zinc finger transcription factors are likely targets for Ni(II) toxicity.

Ni(II) ions are able to hydrolyze Naa-(Ser/Thr) peptide bonds in Naa-(Ser/Thr)-Xaa-His-Zaa sequences. We found that various human transcription factors contain such nickel hydrolytic patterns within C2H2 zinc finger (ZF) domains. We demonstrated the hydrolysis on two peptide models, the 3rd ZF of the Sp1 transcription factor and the 1st ZF of the ZNF302 transcription factor. The experimentally studied reaction rates indicate that the hydrolysis reaction is likely to be an element of intracellular nickel toxicity.

[Prevalence of antibodies to Francisella tularensis in forest workers from different regions of Poland]. / Wystepowanie przeciwcial dlaantygenów Francisella tularensis u pracowników lesnych w wybranych regionach Polski.

In the present study we evaluate the prevalence of antibodies to F. tularensis in 480 serum samples obtained from healthy forest workers from different regions of Poland. The investigations were performed using the tube agglutination test and ELISA. The cut-off limit of serum antibodies was set at mean antibody titre determined in the sera of 115 blood donors exceeded by three standard deviations. In none serum samples we detected antibodies to F. tularensis by tube agglutination test. Of the 480 tested sera IgA antibodies were detected by ELISA in 4.6%, antibodies IgG in 3.8% and antibodies IgM in 2.70% serum samples. The results of our study showed that antibodies to F. tularensis were slightly, but not statistically significant, more often diagnosed in healthy forest workers than healthy blood donors.