Cysteine Reactivity Distinguishes Redox Sensing by the Heat-Inducible and Constitutive Forms of Heat Shock Protein 70

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Highlights? The stress-inducible chaperone Hsp72, but not constitutive Hsc70, is prone to oxidation ? Specific cysteine residues in Hsp72 may be important in redox sensing ? Oxidation of Hsp72 causes degradation of its substrate, tau, in cells     

Early response of lymphocyte proteins after gamma-radiation

In radiation biology there is a recent trend of looking for suitable biological parameters to detect early radiation-induced cellular damage. The present paper mentions 29 early response proteins (ERPRO) in human lymphocytes separated by 2 D-SDS-PA gelelectrophoresis 15 minutes after γ-radiation (2 Gy). A third of these proteins including phosphoproteins were identified using Nano-HPLC-MS. Most of the proteins were structural proteins (β-actin, mutant β-actin, talin and zyxin) except phosphoglycerate kinase-1, an enzyme of the glycolysis. For a more complete and detailed picture of ERPRO, the amount of proteins per gel has to be increased in the future by using a preparative gel instead of an analytical one.     

Delay-coupled discrete maps: Synchronization, bistability, and quasiperiodicity

The synchronization transition is studied in delay-coupled logistic maps. For low coupling, in-phase and out-of-phase synchronous dynamics coexist, and with increasing coupling there is a regime of quasiperiodicity before eventual attraction to a fixed point at a critical value of coupling that depends on the nonlinearity. The presence of a region of asynchrony separating two synchronized regimes—termed anomalous behaviour—has been observed earlier in continuous systems and is shown here to occur in delay mappings as well. There are regions of in-phase, anti-phase, and out-of-phase dynamics of periodic as well as chaotic attractors.     

On zeros of functions of given proximate formal order analytic in a half-plane

We describe sequences of zeros of functionsf≢0 that are analytic in the half-plane ℂ₊={z:Rez> and satisfy the condition

Reactions of trichloro(cyclopentadienyl)titanium(IV) with 1,5-diarylthiocarbazones

Summary The synthesis and characterization of the complexes from the reactions of trichloro(cyclopentadienyl)titanium(IV) with 1,5-diarylthiocarbazones (aryl=phenyl,o-tolyl,o-chlorophenyl,p-tolyl,p-chlorophenyl, or 3,5-dimethylphenyl) are reported. They are of the types CpTi(HDz)Cl₂ and CpTi(HDz)₂Cl (Cp=cyclopentadienyl, HDz^–=the mono-anion of a 1,5-diarylthiocarbazone, H₂Dz). The compounds are nonelectrolytes in dimethylformamide (DMF). In solid state, the far i.r. spectra of CpTi(HDz)Cl₂ indicate the complexes to be dimeric, involving Cl-bridges.     

On Interpolation Sequences of One Class of Functions, Analytic in the Half-Plane

A new criterion of solvability of the interpolation problem f( _n )=b_n in the class of functions f, analytic in the right half-plane and such that there exists c ₁(0;+) such that |f(z)|c ₁exp((c₁|z|)) for all z , where is a positive increasing continuous differentiable function on [0;+), for which (t)+ as t+ and there exists c ₂(0;+) such that

A silicon stress-sensitive unijunction transistor

The performance of a silicon stress-sensitive unijunction transistor is investigated. The transistor is classed as a stress-sensitive semiconductor lateral bipolar device with an S-type input (emitter) I-V characteristic. The optimal layout of the device and its basic parameters are determined. The device can serve as a basis for designing relaxation oscillators with the physically integrated function of mechanical stress-to-signal frequency conversion at the output.     

Absorption,excitation and fluorescence spectra of thallium activated cesium bromide

Absorption, excitation and fluorescence spectra of T1⁺ doped cesium bromide have been investigated at various thallium concentrations. At very low thallium concentration two absorption bands are obtained at 225 nm and 264 nm. With rise of thallium concentration additional absorption bands are obtained at 230, 244, 258, 270 and 285 nm. A single bell-shaped fluorescence band at 357 nm in the ultraviolet region is obtained at low thallium concentration. Two additional visible fluorescence bands appear at 440 and 540 nm with rise in thallium content. The excitation spectra for ultraviolet emission band and visible emission bands are found to be different. Accordingly the ultraviolet emission band is attributed to the characteristic A emission in T1⁺ ion and the visible bands are attributed to dimer centers havingD _4h site symmetry.     

Biological effects induced by swift heavy ions of lithium on aqueous solution of plasmid pMTa4

Biological samples exposed to swift heavy ions sustain damage on different components. Damage to DNA, a critical component of a living system, has considerable biological implications. In this study aqueous solution of plasmid pMTa4 was exposed to varying fluence of swift ⁷Li ions and its different topological forms were analysed by agarose gel electrophoresis to study the induced damage. To monitor radiation labile nucleotide sequence the ⁷Li ions exposed plasmid was degraded by three different restriction endonucleases and also analysed by agarose gel electrophoresis. The results show that ⁷Li ions predominantly induced double strand breaks in the plasmid DNA in a dose-dependent manner and affected preferentially the GC-rich motifs of the DNA. The results suggest that ⁷Li ions induce premutagenic lesions at an enhanced frequency in segments of the DNA which are rich in CG content as compared to GC-poor segments.