Multidrug resistance in cancer is significantly limits the effectiveness of cancer chemotherapy. The main purpose of the present study is to investigate the role of autophagy induced by glucose starvation in apoptosis induction in multidrug resistant human leukemia HL60/ADR cell line. The present data indicates that glucose starvation induced autophagy as determined by the level of LC3 protein (autophagy marker), whereas serum deprivation did not induce autophagy at the same time points. The induction of autophagy by glucose starvation exerted a great effect on apoptosis induction and enhancement. It was found that glucose starvation induced caspase3 cleavage more intensive than serum deprivation. Also, glucose starvation up-regulated the pro-apoptotic BAX and down-regulated the anti-apoptotic BCL-1 proteins representation, but serum deprivation did not affect both protein levels. The lipid mediator, Ceramide was the most candidate key player in autophagy and/or apoptosis induction after glucose starvation. Accordingly, Ceramide level was determined by DGK assay, ceramide level was elevated after glucose starvation and decreased after serum deprivation. Elevation of Ceramide by glucose starvation was found to be due to down-regulation of sphingomyelin synthase and glucosyl ceramide synthase activities and up-regulation of neutral sphingomyelinase activity. The opposite case of these enzyme activities was obtained in serum deprived cells. The current data throw the light on autophagy induced by glucose starvation as a powerful tool for apoptosis induction in multidrug resistance malignancy. Abbreviations: SM; sphingomyelin, Cer; Ceramide, DG; Diethyl Glycerol, SMS; Sphingomyelin Synthase, GCS; Glucosyl ceramide Synthase, GCer; Glucosyl Ceramide, ASMase; Acid Sphingomyelinase, NSMase; Neutral Sphingomyelinase, Glu; Glucose, Ser; Serum, MDR; Multidrug Resistance.

After ligation with transferrin (Tf), transferrin receptor (TfR) is aggregated on cell surface in clathrin coated pits and then internalized into the cell. In the present work, the mechanism of (Tf/TfR) and the role of Ceramide in this mechanism were studied. After Tf/TfR ligation, Ceramide level on plasma membrane outer leaflet was temporarily elevated as clarified by immunocytochemical detection of cell surface Ceramide in human "jurkat" T lymphoma cell line. Ceramide elevation was confirmed by Diacylgelycerol kinase assay for biochemical Ceramide measurement. The fast and brief Cer elevation was the result of acid sphingomyelinase activity, and no detection of neutral sphingomyelinase activity was noticed. Sphingomyelin synthase activity was obviously decreased in the same time frame of Ceramide generation, to maintain the elevated level of Ceramide. Inhibition of Ceramide generation by Imipramine, an acid sphingomyelinase inhibitor, or neutralization of the generated Ceramide by anti-Ceramide mAb lead to miss-internalization of transferrin, instead of being clathrin mediated it becomes, most probably, raft mediated as indicated by altered Tf recycling and cell fractionation studies. Miss-internalization of transferrin leads to abrogation of cell growth and finally apoptotic cell death. Abbreviations: ASMase – Acid Sphingomyelinase; Cer – Ceramide; DGK - Diacylgelycerol kinase; NSMase – Neutral Sphingomyelinase; SM – Sphingomyelin; SMS – Sphingomyelin synthase; Tf – Transferrin; TfR – Transferrin receptor.

A simple spraying technique was employed to deposit nickel hydroxide films on glass substrates. Nickel oxide films with different crystallite size were obtained by post annealing of Ni(OH)2 films in air at 523–673 K. The structure, chemical composition, surface morphology and thickness of the as-deposited and annealed films were investigated using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The crystallite size was found to increase with increasing the annealing temperature. SEM revealed rather homogeneous films with an average thickness of about 10 m. Optical absorption study in 200 - 900 nm wavelength range reveals high absorption for wavelengths (λ) less than 400 nm in the ultraviolet (UV) and visible range. The UV absorption edge of NiO nanostructured films show shorter wavelength-shift that increases with increasing the crystallite size. NiO films exhibit optical transition by both direct and indirect allowed transitions. Direct and indirect optical energy gaps were calculated and found to decrease from 3.25 to 2.87 eV and 3.84 to 3.62 eV respectively; while the width of the localized states increases from 0.306 to 0.586 eV with decreasing the crystallite size from 23.4 to 5.7 nm. Dispersion spectra, real and imaginary parts of the dielectric constant spectra are examined at high frequencies.

A simple spraying technique was employed to deposit nickel hydroxide films on glass substrates. Nickel oxide films with different crystallite size were obtained by post annealing of Ni(OH)2 films in air at 523–673 K. The structure, chemical composition, surface morphology and thickness of the as-deposited and annealed films were investigated using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The crystallite size was found to increase with increasing the annealing temperature. SEM revealed rather homogeneous films with an average thickness of about 10 m. Optical absorption study in 200 - 900 nm wavelength range reveals high absorption for wavelengths (λ) less than 400 nm in the ultraviolet (UV) and visible range. The UV absorption edge of NiO nanostructured films show shorter wavelength-shift that increases with increasing the crystallite size. NiO films exhibit optical transition by both direct and indirect allowed transitions. Direct and indirect optical energy gaps were calculated and found to decrease from 3.25 to 2.87 eV and 3.84 to 3.62 eV respectively; while the width of the localized states increases from 0.306 to 0.586 eV with decreasing the crystallite size from 23.4 to 5.7 nm. Dispersion spectra, real and imaginary parts of the dielectric constant spectra are examined at high frequencies.

A simple spraying technique was employed to deposit nickel hydroxide films on glass substrates. Nickel oxide films with different crystallite size were obtained by post annealing of Ni(OH)2 films in air at 523–673 K. The structure, chemical composition, surface morphology and thickness of the as-deposited and annealed films were investigated using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The crystallite size was found to increase with increasing the annealing temperature. SEM revealed rather homogeneous films with an average thickness of about 10 m. Optical absorption study in 200 - 900 nm wavelength range reveals high absorption for wavelengths (λ) less than 400 nm in the ultraviolet (UV) and visible range. The UV absorption edge of NiO nanostructured films show shorter wavelength-shift that increases with increasing the crystallite size. NiO films exhibit optical transition by both direct and indirect allowed transitions. Direct and indirect optical energy gaps were calculated and found to decrease from 3.25 to 2.87 eV and 3.84 to 3.62 eV respectively; while the width of the localized states increases from 0.306 to 0.586 eV with decreasing the crystallite size from 23.4 to 5.7 nm. Dispersion spectra, real and imaginary parts of the dielectric constant spectra are examined at high frequencies.

The amount of ultraviolet radiation(UVR)reaching the Earth’s surface has been increasing as aresult of an increasingly thinner ozone layer.The UV-A component of the UVR is able to generate oxidative stress in the compound eye and haemo lymph of Procambarus clarkii when the latter was exposed for as little as 15min daily for one week to UV-A.Changes in the eye involved corneal material, crystalline cones, pigments in cones talks and retinula cells, rhabdom integrity, haemocyte in filtration,and haemal spaces. UV-A had significant impacts on haemolymph iron and glucose, where as Ca ions were unaffected.Total Protein and Cu ions showed on lyin significant changes following UV-A radiation.Involvement of lipid peroxidation and DNA fragmentation was significant with regard to the tissue damage cause by the UV-A.UV A further more induced biological effects on serum electrophoretic patterns: some fractions either increased in size or others decreased. The described change scan be used as reference guide lines in evaluations of UV-A induced stress effects in P. clarkii

The amount of ultraviolet radiation(UVR)reaching the Earth’s surface has been increasing as aresult of an increasingly thinner ozone layer.The UV-A component of the UVR is able to generate oxidative stress in the compound eye and haemo lymph of Procambarus clarkii when the latter was exposed for as little as 15min daily for one week to UV-A.Changes in the eye involved corneal material, crystalline cones, pigments in cones talks and retinula cells, rhabdom integrity, haemocyte in filtration,and haemal spaces. UV-A had significant impacts on haemolymph iron and glucose, where as Ca ions were unaffected.Total Protein and Cu ions showed on lyin significant changes following UV-A radiation.Involvement of lipid peroxidation and DNA fragmentation was significant with regard to the tissue damage cause by the UV-A.UV A further more induced biological effects on serum electrophoretic patterns: some fractions either increased in size or others decreased. The described change scan be used as reference guide lines in evaluations of UV-A induced stress effects in P. clarkii