Embedding graphs having Ore-degree at most five

Let $H$ and $G$ be graphs on $n$ vertices, where $n$ is sufficiently large. We prove that if $H$ has Ore-degree at most 5 and $G$ has minimum degree at least $2n/3$ then $H\subset G.$Comment: accepted for publication at SIAM J. Disc. Mat

Lectins and Tetrahymena – A review

The unicellular ciliate Tetrahymena is a complete organism, one of the most highly developed protozoans, which has specialized organelles performing each of the functions characteristic to the cells of higher ranked animals. It is also able to produce, store, and secrete hormones of higher ranked animals and also react to them. It produces lectins that can bind them and has functions, which are influenced by exogenous lectins. The review lists the observations on the relationship between lectins and Tetrahymena and try to construe them on the basis of the data, which are at our disposal. Considering the data, lectins can be used by Tetrahymena as materials for influencing conjugation, for stimulating hormone receptors, and by this, mimic the hormonal functions. Lectins can influence phagocytosis and movement of the cells as well as the cell division. As Tetrahymena can recognize both related and hostile cells by the help of lectins and surface sugars, it could be surmised a complex predator–prey system. This could determine the survival of the population as well as the nourishment conditions. When Tetrahymena is pathogenic, it can use lectins as virulence factors

The Immunoendocrine Thymus as a Pacemaker of Lifespan

The thymus develops from an endocrine area of the foregut, and retains the ancient potencies of this region. However, later it is populated by bone marrow originated lymphatic elements and forms a combined organ, which is a central part of the immune system as well as an influential element of the endocrine orchestra. Thymus produces self-hormones (thymulin, thymosin, thymopentin, and thymus humoral factor), which are participating in the regulation of immune cell transformation and selection, and also synthesizes hormones similar to that of the other endocrine glands such as melatonin, neuropeptides, and insulin, which are transported by the immune cells to the sites of requests (packed transport). Thymic (epithelial and immune) cells also have receptors for hormones which regulate them. This combined organ, which is continuously changing from birth to senescence seems to be a pacemaker of life. This function is basically regulated by the selection of self-responsive thymocytes as their complete destruction helps the development (up to puberty) and their gradual release in case of weakened control (after puberty) causes the erosion of cells and intercellular material, named aging. This means that during aging, self-destructive and non-protective immune activities are manifested under the guidance of the involuting thymus, causing the continuous irritation of cells and organs. Possibly the pineal body is the main regulator of the pacemaker, the neonatal removal of which results in atrophy of thymus and wasting disease and its later corrosion causes the insufficiency of thymus. The co-involution of pineal and thymus could determine the aging and the time of death without external intervention; however, external factors can negatively influence both of them

Biogenic amines at a low level of evolution: Production, functions and regulation in the unicellular Tetrahymena

The unicellular eukaryote Tetrahymena synthesize, store and secrete biogenic amines (histamine, serotonin, epinephrine, dopamine, melatonin) and also can take up amines from the milieu. It also has (G-protein-coupled) receptors (binding sites) for these amines as well, as second messengers. The factors infuencing the mentioned processes are shown. For certain amines the genes and the coded enzymes are demonstrated. The amines influence phagocytosis, cell division, ciliary regeneration, glucose metabolism and chemotaxis. There are interhormone actions between the amines, and between the amines and other hormones produced by Tetrahymena. The critical review discusses the role of amines in the early stages of evolution and compares this to their functions in mammals. It tries to give answer how and why biogenic amines were selected to hormones, and why new functions formed for them in higher ranked animals, preserving also the ancient ones

A fejlődési rendellenesség fogalmának átértelmezése: a hibás perinatalis imprinting jelentősége

Absztrakt A fejlődési rendellenesség klasszikus fogalma a születéskor észlelhető morfológiai rendellenességekre vonatkozott. Később a funkcionális teratogenitás is felismerésre és elfogadásra került, ami a születéssel záruló egyedfejlődés alatti ártalmak általi funkciókárosodásban nyilvánul meg és az élet bármely szakaszában jelentkezhet. Az egyedfejlődés azonban a születéssel nem zárul le, egyes szervrendszereink vagy szerveink a születés után hosszú ideig fejlődési állapotban vannak, és így különböző teratogén faktorok által befolyásolhatók. Különösen lényeges ebből a szempontból a perinatalis időszak, amikor a hormon- és receptorrendszer egymáshoz való beállítódása történik meg és létrejön a hormonális imprinting. Ha ez hibásan történik meg, életre szólóan befolyásolja a receptorok általi hormonkötést és mindazt, ami ennek következménye. A hibás hormonális imprinting tehát funkcionális teratogén és következménye egy fejlődési rendellenességgel egyenértékű zavar azzal súlyosbítva, hogy a hiba az utódgenerációkra is átöröklődik. Hibás imprintinget váltanak ki (állatkísérletekben és az emberi alkalmazáshoz arányosított dózisban is) a receptorszinten ható gyógyszerek, mint az oxitocin, a szteroidhormonok és analógjaik (terhességvédők, fogamzásgátlók, szurfaktánsok), a D- és A-vitamin, a környezetszennyező endokrin diszruptorok (benzpirén, bisphenol A, peszticidek, herbicidek) és egyes szójakomponensek stb. Ebben az értelmezésben mindezek (funkcionális) teratogének, amelyek elkerülése mind a prevenció, mind a terápia szempontjából alapvető jelentőségű. A fejlődési rendellenesség fogalmát tehát ki kell bővíteni azzal, hogy 1. keletkezése nemcsak születés előtt történhet, de perinatalisan, sőt annál később is; 2. az élet bármely időpontjában manifesztálódhat; 3. latens formában is jelen lehet, amit belső vagy külső környezeti faktorok aktiválhatnak; 4. a hibás hormonális imprinting teratogén tényező. Orv. Hetil., 2015, 156(28), 1120–1127

Aromatic hydrocarbon receptors in the immune system: Review and hypotheses

Ah-receptors (AhRs) recognize and bind foreign environmental molecules as well as some target hormones of other nuclear receptors. As ligands activate transcription factors, they transmit the information on the presence of these molecules by binding to the DNA, which in turn activate xenobiotic metabolism genes. Cross talk with other nuclear receptors or some non-nuclear receptors also activates or inhibits endocrine processes. Immune cells have AhRs by which they are activated for physiological (immunity) or non-physiological (allergy and autoimmunity) processes. They can be imprinted by hormonal or pseudo-hormonal (environmental) factors, which could provoke pathological alterations for life (by faulty perinatal hormonal imprinting). The variety and amount of human-made new environmental molecules (endocrine disruptors) are enormously growing, so the importance of AhR functions is also expanding

Hormonalis imprinting a kozponti idegrendszerben: okok es kovetkezmenyek.

The notion of the perinatal "hormonal imprinting" has been published at first in 1980 and since that time it spred expansively. The imprintig develops at the first encounter between the developing receptor and the target hormone - possibly by the alteration of the methylation pattern of DNA - and it is transmitted to the progeny generations of the cell. This is needed for the complete development of the receptor's binding capacity. However, molecules similar to the target hormone (hormone-analogues, drugs, chemicals, environmental pollutants) can also bind to the developing receptor, causing faulty imprinting with life-long consequences. This can promote pathological conditions. Later it was cleared that in other critical periods such as puberty, imprinting also can be provoked, even in any age in differentiating cells. The central nervous system (brain) also can be mistakenly imprinted, which durably influences the dopaminergic, serotonergic and noradrenergic system and this can be manifested - in animal experiments - in alterations of the sexual and social behavior. In our modern age the faulty hormonal imprintig is inavoidable because of the mass of medicaments, chemicals, the presence of hormone-like materials (e.g. soya phytosteroids) in the food, and environmental pollutants. The author especially emphasizes the danger of oxytocin, as a perinatal imprinter, as it is used very broadly and can basically influence the emotional and social spheres and the appearance of certain diseases such as auitism, schizophrenia and parkinsonism. The danger of perinatal imprinters is growing, considering their effects on the human evolution

Online Learning with Gaussian Payoffs and Side Observations

We consider a sequential learning problem with Gaussian payoffs and side information: after selecting an action $i$, the learner receives information about the payoff of every action $j$ in the form of Gaussian observations whose mean is the same as the mean payoff, but the variance depends on the pair $(i,j)$ (and may be infinite). The setup allows a more refined information transfer from one action to another than previous partial monitoring setups, including the recently introduced graph-structured feedback case. For the first time in the literature, we provide non-asymptotic problem-dependent lower bounds on the regret of any algorithm, which recover existing asymptotic problem-dependent lower bounds and finite-time minimax lower bounds available in the literature. We also provide algorithms that achieve the problem-dependent lower bound (up to some universal constant factor) or the minimax lower bounds (up to logarithmic factors)