26 research outputs found
The relationships between the isoelectric point and: length of proteins, taxonomy and ecology of organisms
<p>Abstract</p> <p>Background</p> <p>The distribution of isoelectric point (pI) of proteins in a proteome is universal for all organisms. It is bimodal dividing the proteome into two sets of acidic and basic proteins. Different species however have different abundance of acidic and basic proteins that may be correlated with taxonomy, subcellular localization, ecological niche of organisms and proteome size.</p> <p>Results</p> <p>We have analysed 1784 proteomes encoded by chromosomes of Archaea, Bacteria, Eukaryota, and also mitochondria, plastids, prokaryotic plasmids, phages and viruses. We have found significant correlation in more than 95% of proteomes between the protein length and pI in proteomes – positive for acidic proteins and negative for the basic ones. Plastids, viruses and plasmids encode more basic proteomes while chromosomes of Archaea, Bacteria, Eukaryota, mitochondria and phages more acidic ones. Mitochondrial proteomes of Viridiplantae, Protista and Fungi are more basic than Metazoa. It results from the presence of basic proteins in the former proteomes and their absence from the latter ones and is related with reduction of metazoan genomes. Significant correlation was found between the pI bias of proteomes encoded by prokaryotic chromosomes and proteomes encoded by plasmids but there is no correlation between eukaryotic nuclear-coded proteomes and proteomes encoded by organelles. Detailed analyses of prokaryotic proteomes showed significant relationships between pI distribution and habitat, relation to the host cell and salinity of the environment, but no significant correlation with oxygen and temperature requirements. The salinity is positively correlated with acidicity of proteomes. Host-associated organisms and especially intracellular species have more basic proteomes than free-living ones. The higher rate of mutations accumulation in the intracellular parasites and endosymbionts is responsible for the basicity of their tiny proteomes that explains the observed positive correlation between the decrease of genome size and the increase of basicity of proteomes. The results indicate that even conserved proteins subjected to strong selectional constraints follow the global trend in the pI distribution.</p> <p>Conclusion</p> <p>The distribution of pI of proteins in proteomes shows clear relationships with length of proteins, subcellular localization, taxonomy and ecology of organisms. The distribution is also strongly affected by mutational pressure especially in intracellular organisms.</p
Evaluation of the association between lifestyle risk factors for myopia development and the prevalence of nearsightedness among young adults
Bolesław Wicherkiewicz and his role in the development of new cataract surgery techniques in the late XIX century
Constitutive expression of cathepsin K in the human intervertebral disc: new insight into disc extracellular matrix remodeling via cathepsin K and receptor activator of nuclear factor-κB ligand
Loneliness and its social images in Stephen Daldry's films
Praca dotyczy problemu samotności w społeczeństwie. Ukazuje jej wymiar społeczny oraz psychologiczny. W kolejnych częściach pracy analizie poddana jest historia pojęcia samotności, proces ewolucji pojmowania tego pojęcia w społeczenstwie, a także zmiany dotyczące w rozumieniu tego zjawiska oraz przyczyny, z których owa samotnośc wynika. W pracy poświęcone zostały rozważania na temat powszechnego zjawiska "singlizmu". Bazując na części socjologicznej, w pracy omawiana jest twórczość brytyjskiego reżysera, Stephena Daldry, w którego filmach przedstawiany jest bohater samotny.The paper concerns the topic of loneliness; its social and psychological aspects. In following parts of the thesis I analize the history of the phenomenon of loneliness, its evolutionary process and changes of perceiving the meaning of loneliness in society, as well as the reasons of loneliness. I dedicate a part of the paper to the idea of "singles". Reffering to the sociological part of the work, I analize the filmography of the British director, Stephen Daldry, who has shown in each of his movie, a character that struggles with loneliness and being alone
The Inhibitory Effect of Selected D<sub>2</sub> Dopaminergic Receptor Agonists on VEGF-Dependent Neovascularization in Zebrafish Larvae: Potential New Therapy in Ophthalmic Diseases
Pathological angiogenesis is correlated with many ophthalmic diseases. The most common are exudative age-related macular degeneration and proliferative diabetic retinopathy. The current treatment for these diseases is based on regularly administered anti-VEGF antibodies injections. In the study, we investigated selected D2 dopaminergic receptor agonists, namely bromocriptine, cabergoline and pergolide, on hypoxia-induced neovascularization. We used the zebrafish laboratory model, specifically three-day post fertilization (dpf) Tg(fli-1: EGFP) zebrafish larvae. To induce abnormal angiogenesis of hyaloid-retinal vessels (HRVs) and intersegmental vessels (ISVs), the larvae were treated with cobalt chloride (II) (CoCl2) (a hypoxia-inducing agent) from 24 h post fertilization. The inhibitory role of D2 dopaminergic receptor agonists was investigated using confocal microscopy and qPCR. Additionally, the results were compared to those obtained in the group treated with CoCl2 followed by bevacizumab, the well-known antiangiogenic agent. Confocal microscopy analyses revealed severe deformation of vessels in the CoCl2 treated group, while co-incubation with bromocriptine, cabergoline, pergolide and bevacizumab, respectively, significantly inhibited abnormalities of angiogenesis. The qPCR analyses supported the protective role of the chosen dopaminergic agonists by demonstrating their influence on CoCl2-derived upregulation of vegfaa expression. The present results suggest that the D2 receptor agonists can be considered as a new direction in research for antiangiogenic therapy
Biomechanical testing of trachea in a multidirectional load state
Uszkodzenia tchawicy spowodowane wprowadzeniem rur umożliwiających przywrócenie wentylacji płuc. Identyfikacja parametrów mechanicznych jest konieczna w celu rozpoznania patomechanizmu zmian w tkance, związanych z nieprawidłową przebudową. Uzyskane rezultaty badań mechanicznych pozwoliły na opracowanie modelu matematycznego tchawicy w warunkach wielokierunkowego obciążenia. Umożliwi to przewidywanie nadmiernych lokalnych zaburzeń pól odkształceń i naprężeń tchawicy, występujących podczas wprowadzenia rurki intubacyjnej, które do tej pory nie zostały jeszcze dokładnie zbadane.Tracheal injury caused by the introduction of tubes to restore lung ventilation. Identification of mechanical parameters is necessary in order to identify changes in the pathomechanism of tissue associated with abnormal remodeling. The results of mechanical tests allowed us to develop a mathematical model of the trachea in a multidirectional load conditions. This will allow prediction of excessive local disturbances of the fields of strain and stress in the trachea wall occurring during the insertion of the tracheal tube, which so far have not yet been thoroughly investigated
Ocular toxoplasmosis associated with unilateral pigmentary retinopathy that may mimic retinitis pigmentosa : diagnostic dilemmas
We report a unique case of coexisting pigmentary retinopathy and ocular toxoplasmosis in a young male patient. A 23-year-old man presented with sudden visual deterioration in the left eye (LE). The fundus findings revealed bone spicule-shaped pigment deposits, a slightly pale optic disc, arteriole constriction, cystoid macular edema with an epiretinal membrane, and two small inflammatory chorioretinal scars in the right eye, with a concentric narrowing of the visual field and a nonrecordable multifocal electroretinogram (ERG). An active inflammatory lesion at the border of a pre-existing chorioretinal scar in the macula was found in the LE, with a central scotoma in the visual field. Moreover, the patient tested positive for anti-Toxoplasma gondii immunoglobulin G antibodies and showed positive results in polymerase chain reaction testing of aqueous humor. Fluorescein angiography revealed hyperfluorescence in the early phase with fluorescein leakage. A multifocal ERG of the LE showed selective loss of responses from the central 10 degrees. Genetic testing revealed heterozygosity in the RP1 and CELSR1 genes. Our case illustrates challenges in the diagnosis of unilateral pigmentary retinopathy. Based on the typical toxoplasmic lesions in the LE and two scars likely caused by inflammation, our patient was diagnosed with pigmentary retinopathy probably related to toxoplasmosis. Genetic consultation did not confirm the diagnosis of retinitis pigmentosa, but more advanced tests might be needed to definitively exclude it
How Gene Survival Depends on Their Length
Abstract. Gene survival depends on the mutational pressure acting on the gene sequences and selection pressure for the function of the gene products. While the probability of the occurrence of mutations inside genes depends roughly linearly on their length, the probability of elimination of their function does not grow linearly with the length because of the intragenic suppression effect. Furthermore, the probability of redefinition of the stop and start codons is independent of the gene length while shortening of gene sequences by generating stop codons inside gene sequences depends on gene length