Photodynamic therapy (PDT) combining treatment with a light-excited compound and laser light induction, via cellular ROS generation, kills cancer cells by damaging organelles and impairing metabolic pathways. As the exact mechanisms underlying cancer cell death due to PDT treatment remain controversial, the influence of photosensitizer itself, protoporphyrin IX (PpIX) on cancer cells was invest...

Mitomycin C (MMC), a DNA-damaging agent, is a potent inducer of the bacterial SOS response; surprisingly, it has not been used to select resistant mutants from wild-type Escherichia coli. MMC resistance is caused by the presence of any of four distinct E. coli genes (mdfA, gyrl, rob, and sdiA) on high-copy-number vectors. mdfA encodes a membrane efflux pump whose overexpression results in broad...

Muhammad Elmussareh,MRCS, Specialist Registrar in Urology; Ahmed Mahrous, FRCS(Urol), Urology Fellow; Oliver Kayes, FRCS(Urol), Consultant Urologist, St James’s University Hospital, Leeds Around 15% of couples experience infertility, with up to 50% of these related to male factors. Oxidative stress caused by reactive oxygen species, including oxygen ions, free radicals and peroxides, has been r...

The Saccharomyces cerevisiae PNT1 gene was isolated and characterized. When present in high copy number in S. cerevisiae, PNT1 confers resistance to the anti-Pneumocystis carinii drug pentamidine. The PNT1 gene encodes a previously uncharacterized polypeptide of 409 amino acids. The predicted gene product is a very basic (pI 9.9) polypeptide with one potential membrane-associated region. PNT1 i...

Necrosis, apoptosis and autophagic cell death are the main cell death pathways in multicellular organisms, all with distinct and overlapping cellular and biochemical features. DNA damage may trigger different types of cell death in cancer cells but the molecular events governing the mode of cell death remain elusive. Here we showed that increased BH3-only protein BIK levels promoted cisplatin- ...

Polymyxin B and colistin (polymyxin E) are bactericidal pentacationic lipopeptides that act specifically on Gram-negative bacteria, first by disrupting their outermost permeability barrier, the outer membrane (OM), and then damaging the cytoplasmic membrane. Both were discovered in the mid-1950s and subsequently used in intravenous therapy, but soon largely abandoned because of nephrotoxicity. ...

Fibrillar protein aggregates (amyloids) are involved in several common pathologies, e.g., Alzheimer's disease and type II diabetes. Accumulating evidence suggests that toxicity in amyloid-related diseases originates from the deposition of protein aggregates on the cell membrane, which results in bilayer disruption and cell leakage. The molecular mechanism of damage to the membrane, however, is ...

Background: Plasma membrane of the spermatozoa interacts with and is altered by abundant seminal PDC-109 present in their immediate milieu in vivo with damaging effect in a time- and concentration- dependent manner. Therefore we hypothesized that sequestration of detrimental protein from ejaculates would be beneficial for cryopreservation of sperm cells. To this aim we evaluated the effect of s...

objective: this study investigated tissue damages induced by chronic subcutaneous administration of nano- and microparticles of manganese dioxide (mno2) on the liver, kidneys and testes of rats. methods: rats (n=210) were divided into three groups: control, mno2 nanoparticle injected and mno2 microparticle injected. the experimental groups received subcutaneous injections with either nano- or m...