Virulence of Bacteria Colonizing Vascular Bundles in Ischemic Lower Limbs.

Background: We documented previously the presence of bacterial flora in vascular bundles, lymphatics, and lymph nodes of ischemic lower limbs amputated because of multifocal atheromatic changes that made them unsuitable for reconstructive surgery and discussed their potential role in tissue destruction. The question arose why bacterial strains inhabiting lower limb skin and considered to be saprophytes become pathogenic once they colonize deep tissues. Bacterial pathogenicity is evoked by activation of multiple virulence factors encoded by groups of genes.

Chronic lower limb wounds evoke systemic response of the lymphatic (immune) system.

Wound healing should not be considered as a process limited only to the damaged tissues. It is always accompanied by an intensive local immune response and in advanced stages, the systemic lymphatic (immune) structure. In this review we present evidence from our own studies as well as pertinent literature on the role of skin and subcutaneous tissue lymphatics at the wound site and of transport of antigens along with collecting afferent lymphatics to the lymph nodes.

Skin own bacteria may aggravate inflammatory and occlusive changes in atherosclerotic arteries of lower limbs.

Aim: Seroepidemiological studies have given rise to the hypothesis that microorganisms like Chlamydia pneumoniae (CP), Helicobacter pylori (HP), cytomegalovirus (CMV), HCV types 1 and 2, and bacteria involved in dental or other unspecified infection sites may initiate or maintain the atherosclerotic process in lower limb arteries. However, not much attention has been attached to the patient's own limb skin and deep tissues bacterial flora, activated in ischemic tissues. This flora may enhance the inflammatory and thrombotic process in the atherosclerotic arteries.

[BNIP3 as an atypical representative of the Bcl-2 protein family. Part 2: Regulation of the expression and activity of BNIP3 protein and its role in tumorigenesis].

BNIP3 belongs to the Bcl-2 protein family that regulates programmed cell death. It is the only known pro-apoptotic protein expressed during hypoxia and this effect is determined by the HIF-1 responsive element in the bnip3 promoter. However, there is evidence that hypoxia is not a sufficient factor to activate BNIP3; possible cell death dependent on this protein occurs as a result of secondary effects of oxygen deprivation, such as acidosis.

[BNIP3 as an atypical representative of the Bcl-2 protein family. Part 1: BNIP3, a regulator of non-apoptotic programmed cell death].

BNIP3 is classified as a member of the Bcl-2 protein family that regulates programmed cell death and of the BH3-only protein subfamily as it only contains one BH domain. However, the transmembrane domain of BNIP3 is involved in at least some of its pro-apoptotic functions. Although there are some similarities between BNIP3 and other BH3-only proteins, for example the ability to interact with anti-apoptotic Bcl-2 proteins and to induce cytochrome c release from mitochondria, BNIP3 is undoubtedly distinct in regard to its activity and regulatory mechanisms.