Among royal jelly's (RJ) various biological activities, its possible antitumour activity deserves particular attention. The purpose of this study was to investigate the influence of RJ, its bioactive ...component 10-hydroxy-2-decenoic acid (10- HDA), and human interferon-alpha (HuIFN-αN3) on the proliferation of human colorectal adenocarcinoma cells (CaCo- 2), and ascertain their effect on intracellular glutathione (GSH) level and lipid peroxidation. We studied the antiproliferative (AP) activity of RJ (0.1 g/10 mL phosphate buffer saline (PBS), HuIFN-αN3 (1000 I.U. mL⁻¹), 10-HDA at 100.0 μmol L⁻¹, and their different combinations, in the ratio 1:1, 1:2, and 2:1 on CaCo-2 cells. The GSH level was measured by glutathione assay. The lipid peroxidation was measured by malondialdehyde (MDA) assay. Single RJ had a low AP activity: 2.0 (0.5 mg mL⁻¹). HuIFN-αN3 had an AP activity of 2.5 (208.33 I.U. mL⁻¹), while 10-HDA had an AP activity of 1.5 (37.5 μmol mL⁻¹). The highest AP activity of 3.8 was obtained when RJ and HuIFN-αN3 were applied at the ratio 2:1. In that combination the level of GSH was 24.9±2.4 nmol g⁻³ of proteins (vs. 70.2±3.2 nmol g⁻³ in the control) and the level of MDA was 72.3±3.1 nmol g⁻³ (vs. 23.6±9.1 nmol g⁻³ in the control). It is generally assumed that 10-HDA, an important constituent of RJ, together with HuIFN-αN3, is responsible for the inhibition of CaCo-2 cells proliferation in vitro. In our study, however, RJ and HuIFN-αN3 applied at 2:1 decreased the level of GSH the most and significantly increased lipid peroxidation via MDA in CaCo-2 cells. Future studies should show whether these GSH- and MDA-related activities of RJ, HuIFN-αN3, 10-HDA, and their combinations may decrease the tumorigenicity index and tumorigenic potential of various tumour cells in vitro.
Among royal jelly’s (RJ) various biological activities, its possible antitumour activity deserves particular attention. The purpose of this study was to investigate the influence of RJ, its bioactive ...component 10-hydroxy-2-decenoic acid (10- HDA), and human interferon-alpha (HuIFN-αN3) on the proliferation of human colorectal adenocarcinoma cells (CaCo- 2), and ascertain their effect on intracellular glutathione (GSH) level and lipid peroxidation. We studied the antiproliferative (AP) activity of RJ (0.1 g/10 mL phosphate buffer saline (PBS), HuIFN-αN3 (1000 I.U. mL-1), 10-HDA at 100.0 μmol L-1, and their different combinations, in the ratio 1:1, 1:2, and 2:1 on CaCo-2 cells. The GSH level was measured by glutathione assay. The lipid peroxidation was measured by malondialdehyde (MDA) assay. Single RJ had a low AP activity: 2.0 (0.5 mg mL-1). HuIFN-αN3 had an AP activity of 2.5 (208.33 I.U. mL-1), while 10-HDA had an AP activity of 1.5 (37.5 μmol mL-1). The highest AP activity of 3.8 was obtained when RJ and HuIFN-αN3 were applied at the ratio 2:1. In that combination the level of GSH was 24.9±2.4 nmol g-3 of proteins (vs. 70.2±3.2 nmol g-3 in the control) and the level of MDA was 72.3±3.1 nmol g-3 (vs. 23.6±9.1 nmol g-3 in the control). It is generally assumed that 10-HDA, an important constituent of RJ, together with HuIFN-αN3, is responsible for the inhibition of CaCo-2 cells proliferation in vitro. In our study, however, RJ and HuIFN-αN3 applied at 2:1 decreased the level of GSH the most and significantly increased lipid peroxidation via MDA in CaCo-2 cells. Future studies should show whether these GSH- and MDA-related activities of RJ, HuIFN-αN3, 10-HDA, and their combinations may decrease the tumorigenicity index and tumorigenic potential of various tumour cells in vitro.
Kot del biološke aktivnosti MM (Matičnega mlečka) so avtorji preučevali njegovo protitumorsko delovanje kot tudi možno interakcijo s humanim interferonom alfa (HuIFN-αN3). Cilj opravljenih poskusov je bil preučiti vpliv kombinacije med MM in HuIFN-αN3 na proliferacijo celic Humanega kolorektalnega adenokarcinoma (CaCo-2) in njun vpliv na znotrajcelični nivo glutationa (GSH) in peroksidacijo lipidov. Avtorji so preučevali AP (Antiproliferativno) delovanje MM (0.1 g/10 mL fosfatnega pufra) (PBS), HuIFN-αN3, (1000 I.U. mL-1), 10-hidroxy-2-decenoične kisline (10-HDA) (100.0 μmol L-1) in različne kombinacije med njimi (1:1, 1:2 in 2:1) na celice CaCo-2 in vitro. Njihov vpliv na znotrajcelični nivo GSH so merili s pomočjo komercialnega kita. Peroksidacijo lipidov so merili s pomočjo meritve vrednosti malondialdehida (MDA). MM sam kaže AP aktivnost 2.0 (0.5 mg mL-1 ). HuIFN-αN3 ima AP aktivnost 2.5 (208.33 I.U. mL-1) medtem ko ima 10-HDA AP aktivnost 1.5 (37.5 μmol mL-1). AP aktivnost kombinacije MM:HuIFN-αN3 (2:1) je bila 3.8. Pri tej kombinaciji je bil viden vpliv na nivo GSH: 24.9±2.4 nmol g-3 proteinov (70.2±3.2 nmol g-3 pri kontroli). Nivo MDA je bil 72.3±3.1 nmol g-3 pri kontroli). 10-HDA je glavna sestavina MM, ki v kombinaciji s HuIFN-αN3 deluje antiproliferativno na CaCo-2 celice. MM in HuIFN-αN3 v kombinaciji 2:1 pospešujeta peroksidacijo lipidov (MDA) in zmanjšujeta nivo glutationa (GSH). Nadaljni poskusi bodo pokazali ali z GSH- in MDA- povezane aktivnosti MM, HuIFN-αN3, 10-HDA in kombinacij med njimi, zmanjšujejo indeks tumorigenosti in s tem tumorigeni potencijal različnih tumorskih celic in vitro.
One considers an unbounded, anisotropic elastic body containing an elliptical hole free from external loads but loaded by shear stresses far from the hole. The anti-plane equilibrium of the ...anisotropic elastic body is determined by using the complex representation of the anti-plane elastic states and the conformal mapping technique. The solution is obtained in compact, elementary form. One verifies by direct calculus that the obtained solution satisfies all boundary conditions. When the smaller semiaxis of the elliptical hole tends to zero; i.e. the hole becomes the classical Griffith-Irwin crack; the potential obtained for the elliptic hole case tends then to that obtained for the classical crack problem by solving the corresponding Riemann-Hilbert problem.
The problem considered is the antiplane deformation in prestressed and prepolarized piezoelectric crystals in equilibrium. The representation of the general solution is derived in terms of complex ...potentials for all piezoelectric crystal classes in which an antiplane state is possible. This generalizes earlier results obtained in respect of a specific crystal class. The general formulae are specialized to find the antiplane state generated by a Mode-III crack.
In this paper, we analyze the consequences of Sih’s fracture criterion in a material which behaves according to the Cosserat-type model with free or constrained rotations. Both models are considered ...and for each of them the first and the second fracture mode is analyzed. To apply Sih’s criterion, the singular part of the stress field and of the couple stress field in the neighborhood of the crack tip are determined. The direction of the crack propagation predicted by the model with constrained rotations contradicts the experimental results for both modes of fracture. The qualitative predictions of the model allowing free rotations are in good agreement with experimental data only if the material constant newly introduced satisfies certain restrictions, which are more severe in the case of the second fracture mode. The conclusion is that the two Cosserat models do not improve significantly the predictions of the classical model of crack propagation in elastic solids.
The general complex‐variable solution to the equations of incremental antiplane piezoelectricity is used to solve the problem of crack propagation in a crystal in the presence of an initial stress ...and electric field. Remote incremental antiplane tractions are specified and an incremental traction of the same intensity is applied to the crack faces. The initial fields are shown to have a pronounced effect on the near‐tip stresses and on the displacements of the crack faces. Griffith's criterion is used to determine the combination of electromechanical parameters required for incipient crack propagation.
Griffith's notion of energy-release rate is extended to the linearized incremental theory of pre-stressed and pre-polarized piezoelectric crystals under suitable restrictions on the pre-existing ...fields.
We study piezoelectric crystals under antiplane strain in the presence of preexisting mechanical and electrical fields. The general representation of the solution is derived for the crystal class 42m ...in terms of complex potentials.
Premda hepatitis B nije česta bolest u SAD-u, EU, pa ni u Hrvatskoj, a zaraza se ne javlja kao epidemija, prema odlukama nadležnih vlasti sva se djeca trebaju cijepiti tri puta. Prvo je cijepljenje ...nakon poroda, prije otpuštanja iz rodilišta. Tu su odluku u SAD-u financijskim donacijama podržale velike farmaceutske korporacije.
U posljednje vrijeme u medicinskoj literaturi sve je više izvješća o pojavi brojnih zdravstvenih problema (kronične bolesti imunološkog i nervnog sustava) nakon cijepljenja djece i odraslih protiv hepatitisa B. Znanstvenici upozoravaju da genetski modificirano cjepivo protiv hepatitisa B sadrži polipeptidnu sekvencu mielin, koja je prisutna i u ljudskom nervnom tkivu. Mehanizmom molekalarne mimikrije ovaj polipeptid može djelovati kao autoantigen i izazvati bolesti autoimune demielinizacije mozga poput multiple skleroze i niza poteškoća u razvoju. Prema Programu cijepljenja u Hrvatskoj je obvezno cijepljenje protiv hepatitisa B uvedeno 1999., a za novorođenčad 2007. godine. Potreba za ovakvom mjerom kritički je raspravljana.
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