Face and body sponges: beauty aids or potential microbiological reservoir?

Small natural or synthetic sponges are commonly used in daily hygiene and in removing make-up. In our study we try to assess the role of sponges as reservoirs and vehicles in the transmission of potentially pathogenic bacterial species. We demonstrate that numerous Gram-negative and Gram-positive bacterial species are detectable in sponges after normal use by the healthy population.

Cell shape and plasma membrane alterations after static magnetic fields exposure.

The biological effects of static magnetic fields (MFs) with intensity of 6 mT were investigated in lymphocytes and U937 cells in the presence or absence of apoptosis-inducing drugs by transmission (TEM) and scanning (SEM) electron microscopy. Lectin cytochemistry of ConA-FITC conjugates was used to analyze plasma membrane structural modifications. Static MFs modified cell shape, plasma membrane and increased the level of intracellular [Ca++] which plays an antiapoptotic role in both cell types.

Kupffer cells promote lead nitrate-induced hepatocyte apoptosis via oxidative stress.

BACKGROUND: Apoptosis and its modulation are crucial factors for the maintenance of liver health, allowing hepatocytes to die without provoking a potential harmful inflammatory response through a tightly controlled and regulated process. Since Kupffer cells play a key role in the maintenance of liver function, the aim of this study was to verify whether Kupffer cells are involved in the induction of liver apoptosis after i.v.

Morphological and ultrastructural analysis of Turritopsis nutricula during life cycle reversal.

The hydrozoa life cycle is characterized, in normal conditions, by the alternation of a post-larval benthic polyp and an adult pelagic medusa; however, some species of Hydrozoa react to environmental stress by reverting their life cycle: i.e. an adult medusa goes back to the juvenile stage of polyp.

Lead nitrate and gadolinium chloride administration modify hepatocyte cell surfaces.

Modifications of hepatocyte cell surface were determined after single i.v. injection to rats of Pb(NO(3))(2) (known to induce liver hyperplasia followed by apoptosis) or GdCl(3) (known to induce proliferation of parenchymal cells and Kupffer cell depletion) or administration of GdCl(3) 24 h before Pb(NO(3))(2) injection (known to reduce hyperplasia and apoptosis induced in the parenchymal liver cells by the single Pb(NO(3))(2) injection).

Phagocytosis of apoptotic cells by liver: a morphological study.

The present review deals with the morphological features of the removal of apoptotic cells by liver. The engulfment of cells undergoing apoptosis can be considered a specialized form of phagocytosis, playing a major role in the general tissue homeostasis in physiological and pathological conditions. In fact, defects of phagocytosis of apoptotic cells might have deleterious consequences for neighboring healthy cells, i.

Synchronized onset of nuclear and cell surface modifications in U937 cells during apoptosis.

In this study we investigated the relationship between nuclear and cell surface modifications (i.e. blebbing, phosphatidylserine [PS] and sugar residues exposure) in a monocytic cell line, U937, during apoptosis induced by oxidative stress (1 mM H2O2) or inhibition of protein synthesis (10 microg/ml puromycin).

Cell shape and organelle modification in apoptotic U937 cells.

U937 cells induced to apoptosis, progressively and dramatically modified their cell shape by intense blebbing formation, leading to the production of apoptotic bodies. The blebs evolved with time; milder forms of blebbing involving only a region or just the cortical part of the cytoplasm were observed within the first hour of incubation with puromycin; blebbing involving the whole cell body with very deep constrictions is the most frequent event observed during late times of incubation. The ultrastructural analysis of apoptotic cells revealed characteristic features of nuclear fragmentation (budding and cleavage mode) and cytoplasmatic modifications.

Modulation of cell surface expression of liver carbohydrate receptors during in vivo induction of apoptosis with lead nitrate.

Cell surface expression of carbohydrate receptors (i.e. mannose and galactose receptors) and phagocytosis of apoptotic cells by sinusoidal liver cells was studied.

Hepatic sinusoidal endothelium heterogeneity with respect to the recognition of apoptotic cells.

The recognition and removal of human apoptotic peripheral lymphocytes in selected populations of periportal and perivenous endothelial cells was studied in in situ and in vitro experiments. Apoptotic peripheral blood lymphocytes once injected into the liver circulation were retained by the sinusoids showing a large heterogeneity of distribution: apoptotic cells are found in the periportal tract double the amount found in the perivenous region. Apoptotic PBL adhesion was lowered to a sixth of the control after preinjection with a sugar mixture (Mannose, N-acetylgalactosamine, N-acetylglucosamine, D-galactose), as suggested by the expression of modified surface glycoconjugates on the plasma membrane of apoptotic cells.

Relationship between cellular shape and receptor-mediated endocytosis: an ultrastructural and morphometric study in rat Kupffer cells.

The relationship between cellular shape (i.e., size, volume, presence of microvilli, pseudopodia, flat or round shape) and receptor-mediated endocytotic activities (i.