Derivatives of the cytotoxic peptide dermaseptin S4 have recently emerged as potential antimicrobial agents. Here, we report on the antibacterial properties of three derivatives with improved toxicity profiles: a 28-residues K4K20-S4 and two shorter versions, K4-S4(1-16) and K4-S4(1-13). The range of MICs of K4K20-S4 against clinical isolates of Staphylococcus aureus, Pseudomonas aeruginosa, an...

A decomposition of λ copies of monochromatic Kv into copies of K4 such that each copy of K4 contains at most one edge from each Kv is called a proper edge coloring of a BIBD(v, 4, λ). We show that the necessary conditions are sufficient for the existence of a BIBD(v, 4, λ) which has such a proper edge coloring.

Motivated by previous results on distance constrained labelings and coloring of squares of K4-minor free graphs, we show that for every p ≥ q ≥ 1, there exists ∆0 such that every K4-minor free graph G with maximum degree ∆ ≥ ∆0 has an L(p, q)-labeling of span at most qb3∆(G)/2c. The obtained bound is the best possible.

We show that every K4-minor free graph with toughness greater than 4/7 has a 2-walk, i.e., a closed walk visiting each vertex at most twice. We also give an example of a 4/7-tough K4-minor free graph with no 2-walk.

Seymour proved that the set of odd circuits of a signed binary matroid (M; ) has the Max-Flow Min-Cut property if and only if it does not contain a minor isomorphic to (M(K4); E(K4)). We give a shorter proof of this result.

Kallikrein 4 (KLK4) is a member of the human KLK gene family of serine proteases, many of which are implicated in hormone-dependent cancers. Like other KLKs, such as KLK3/PSA and KLK2, KLK4 gene expression is also regulated by steroid hormones in hormone-dependent cancers, although the transcriptional mechanisms are ill defined. Here, we have investigated the mechanisms mediating the hormonal r...

BACKGROUND Serum lipoprotein(a) [Lp(a)] concentration is largely determined by variability at the apolipoprotein(a) gene locus. Most prominent effects relate to polymorphisms in the promoter (a pentanucleotide [PN] repeat) and coding regions (a kringle IV [K4] repeat), the latter of which also affects Lp(a) particle size. The impact of these polymorphisms on cardiovascular risk is poorly unders...

In this paper, we propose a polynomial-time algorithm to test whether a given graph contains a subdivision of K 4 as an induced subgraph.

Histone-methyl transferases (HMTs) are key enzymes that post-translationally modify histones, and serve key role in gene expression, epigenetic regulation, and as determinants of survival in malignant cells. Recent studies have shed light on the role of hSET1 which is a key element of highly conserved multi-protein HMT complex that catalyze methylation of histone H3 lysine 4 (H3K4) regulating e...