Interpretation of living tissue's temperature oscillations by thermal wave theory

The fact that the temperature of living tissue may respond oscillatorily to externalheating has been a classical difficulty in the field of bioheat transfer for a long time.Roemer et al. have carefully discussed this in their serial articles, but experiments did notsupport their conclusions, Tharp et al. have artificially made a time-delay differential equs-tion to describe this phenomenon, but their model is short of a strict theoretical founda-

Nonlinear analysis of a non-Fourier heat conduction problem in a living tissue heated by laser source

The effect of laser, as a heat source, on a one-dimensional finite living tissue was stud- ied in this paper. The dual phase lagging （DPL） non-Fourier heat conduction model was used for thermal analysis. The thermal conductivity was assumed temperature- dependent, resulting in a nonlinear equation. The obtained equations were solved using the approximate-analytical Adomian decomposition method （ADM）. It was concluded that the nonlinear analysis was important in nomFourier heat conduction problems. Moreover, a good agreement between the present nonlinear model and experimental result was obtained.

Spatial-Temporal Quantitative Global Energy Differences between the Living and Dead Human Brain

The dynamic differences between a living human brain and a clinically dead (fixed) human brain were measured over international Quantitative Electroencephalographic (QEEG) sites for 1 Hz increments between 1 Hz and 50 Hz. Although the expected greater power (μV2•Hz–1) for the living brain was apparent, the difference was particularly obvious for theta and low beta bands. The integrated square root values over the entire band indicated the difference in intrinsic charge-based energy between the living (higher) and dead brain was ~2•10–23 J. This quantity is remarkably proximal to the Cosmic Background Microwave value and would be consistent with the Hameroff-Penrose definition of consciousness that suggests a permeating presence derived from discrete physical events. A power value obtained by multiplying this increment of energy by the frequency of the universal hydrogen line resulted in ~10–12 W•m–2 when applied to the surface area of the human cerebrum. This value is the median flux density that has been measured from human brains during cognition and defines the ultra-weak photon emissions displayed by cells, tissue, and organisms. These results suggest that modern technology may now be sufficiently precise to discern the critical parameters that differentiate the living brain from the fixed “dead” brain. This information might be useful for future designs of virtual consciousness and simulations within cerebral space.

Comparative Study on the Dielectric Properties Between Living and Non-living from Human and Animal Livers

The data of dielectric properties of human tissues mainly come from animal tissues or human corpse at present. Up to now, there has not been a report of dielectric properties of human living liver. Our objective is to study the dielectric properties of human living liver and compare the results with those of animal living liver as well as the human non-living liver. In vitro measurements of living and non-living livers from human and rabbits are shown in the 10 Hz to 100 MHz range. Analysis of the conductivity, permittivity and characteristic parameters from the data were made. The conductivity of three kinds of liver were markedly different at low frequency of 0.06 s/m (living rabbit liver), 0.13 s/m (living human liver) and 0.24 s/m (non-living human liver). The Cole parameters that best characterize the liver of human and rabbit are R0 , fc1 , R1 , and R∞ The Cole parameters that best characterize the living and nonliving liver of human are R0 , fc1 , ΔR1 , ΔR2 and R ∞ . In conclusion, we can't substitute the dielectric properties of animal or human corpse liver for the living human liver. The results suggest that the dielectric properties of living human tissues has great significance on studying.

Functionalization of in vivo tissue-engineered living biotubes enhance patency and endothelization without the requirement of systemic anticoagulant administration

Vascular regeneration and patency maintenance,without anticoagulant administration,represent key developmental trends to enhance small-diameter vascular grafts(SDVG)performance.In vivo engineered autologous biotubes have emerged as SDVG candidates with pro-regenerative properties.However,mechanical failure coupled with thrombus formation hinder translational prospects of biotubes as SDVGs.Previously fabricated poly(ε-caprolactone)skeleton-reinforced biotubes(PBs)circumvented mechanical issues and achieved vascular regeneration,but orally administered anticoagulants were required.Here,highly efficient and biocompatible functional modifications were introduced to living cells on PB lumens.The 1,2-dimyristoyl-sn-glycero-3-phosphoethanolamine-N-methoxy(DMPE)-PEG-conjugated anti-coagulant bivalirudin(DPB)and DMPE-PEG-conjugated endothelial progenitor cell(EPC)-binding TPS-peptide(DPT)modifications possessed functionality conducive to promoting vascular graft patency.Co-modification of DPB and DPT swiftly attained luminal saturation without influencing cell viability.DPB repellent of non-specific proteins,DPB inhibition of thrombus formation,and DPB protection against functional masking of DPT’s EPC-capture by blood components,which promoted patency and rapid endothelialization in rat and canine artery implantation models without anticoagulant administration.This strategy offers a safe,facile,and fast technical approach to convey additional functionalization to living cells within tissue-engineered constructs.

Ratiometric and selective two-photon fluorescent probe based on PET-ICT for imaging Zn^(2+)in living cells and tissues

A two-photon fluorescent probe TPZn was developed for specific ratiometric imaging Zn2＋ in living cells and tissues. Significant ratiometric fluorescence change was based on photoinduced electron transfer and intramolecular charge transfer. The synthetic method of TPZn was simple. It was successfully used to selectively image Zn2＋ based on the higher binding affinity for Zn2＋ than for Cd2＋. TPZn was easily loaded into the living cell and tissues with high membrane permeability in a complex biological environment. TPZn could clearly visualize endogenous Zn2＋ by TP ratiometric imaging in hippocampal slices at a depth of 120 μm. Thus, TPZn is a useful tool to image of Zn2＋ in living cells and tissues without interference from Cd2＋.

Comparative Study on the Dielectric Properties Between Living and Non-living from Human and Animal Livers

The data of d ieleclric properties of hum an tissues m ably com es from an in al tissues or hum an corpse at present U p to now, there has not been a report of dielectric properties of human living liver. This paper aims to studying the dielectric properties of hum an living liver and corn paring the results with those of an in al living liver as well as the human non-livhg liver. In vitro measurements of living and non-living livers from human and rabbitare shown in the range of 10 Hz to 100 MHz. Analysis of the conductivity, perm ittivity and characteristic param eters from the data were made. The conductivity of three kinds of liver were markedly different at low frequency： 0.06 S/m （living rabbit liver）, 0.13 S/m （living hum an liver） and 0.24 S/m （non-living hum an liver）; The Cole param eters that best characterize the liver of hum an and rabbit are RO, fc1,△R I and R ∞ ;The Cole param eters that best characterize the living and non-living liver ofhum an are RO, fc1,△R I,△R2 and R ∞. In conclusion,we can＇t substitute the dielectric properties of anin al or hum an corpse liver for the living human liver. The results suggest that the study on the dielectric properties of living hum an tissues has great sign ificance.