Can Carpobrotus edulis, heal incisional and excisional wounds on the skin?

OBJECTIVES: This study aimed to investigate the wound healing activity of liposomal Carpobrotus edulis powder extract (CEPE) formulation on incisional and excisional wounds in rat. BACKGROUND: In the event of any damage, the damaged tissue undergoes a process of regenerating itself, which is called wound healing. METHODS: Centella asiatica extract (CAE) was used as the reference molecule in the study. The wound healing process was tested by using the excisional and incisional wound model. On the 12th day of the study, maximum stress, stress, % of elongation values were evaluated in the incisional wound. Also; histological parameters and macroscopic photographic analyses were evaluated in the excisional wound. RESULTS: In the photo evaluations, the improvement was more prominent in both CAE and CEPE groups than in the control group. Histological evaluation showed that CEPE group had significant wound healing activity compared to the control and CAE groups. Axial tensile-elongation experiments in incisional wound tissue show that there was no significant difference between CAE and CEPE groups. CONCLUSION: Liposomal formulations of C.edulis extract were found to have positive effects on the healing process, both on excisional and incisional wound tissues (Tab. 2, Fig. 3, Ref. 30).

Development of a construct-based risk assessment framework for genetic engineered crops.

Experience gained in the risk assessment (RA) of genetically engineered (GE) crops since their first experimental introductions in the early nineties, has increased the level of familiarity with these breeding methodologies and has motivated several agencies and expert groups worldwide to revisit the scientific criteria underlying the RA process. Along these lines, the need to engage in a scientific discussion for the case of GE crops transformed with similar constructs was recently identified in Argentina. In response to this need, the Argentine branch of the International Life Sciences Institute (ILSI Argentina) convened a tripartite working group to discuss a science-based evaluation approach for transformation events developed with genetic constructs which are identical or similar to those used in previously evaluated or approved GE crops. This discussion considered new transformation events within the same or different species and covered both environmental and food safety aspects. A construct similarity concept was defined, considering the biological function of the introduced genes. Factors like environmental and dietary exposure, familiarity with both the crop and the trait as well as the crop biology, were identified as key to inform a construct-based RA process.

State observers and Kalman filtering for high performance vibration isolation systems.

There is a strong scientific case for the study of gravitational waves at or below the lower end of current detection bands. To take advantage of this scientific benefit, future generations of ground based gravitational wave detectors will need to expand the limit of their detection bands towards lower frequencies. Seismic motion presents a major challenge at these frequencies and vibration isolation systems will play a crucial role in achieving the desired low-frequency sensitivity. A compact vibration isolation system designed to isolate in-vacuum optical benches for Advanced Virgo will be introduced and measurements on this system are used to present its performance. All high performance isolation systems employ an active feedback control system to reduce the residual motion of their suspended payloads. The development of novel control schemes is needed to improve the performance beyond what is currently feasible. Here, we present a multi-channel feedback approach that is novel to the field. It utilizes a linear quadratic regulator in combination with a Kalman state observer and is shown to provide effective suppression of residual motion of the suspended payload. The application of state observer based feedback control for vibration isolation will be demonstrated with measurement results from the Advanced Virgo optical bench suspension system.

A state observer for the Virgo inverted pendulum.

We report an application of Kalman filtering to the inverted pendulum (IP) of the Virgo gravitational wave interferometer. Using subspace method system identification techniques, we calculated a linear mechanical model of Virgo IP from experimental transfer functions. We then developed a Kalman filter, based on the obtained state space representation, that estimates from open loop time domain data, the state variables of the system. This allows the observation (and eventually control) of every resonance mode of the IP mechanical structure independently.

Directional limits on persistent gravitational waves using LIGO S5 science data.

The gravitational-wave (GW) sky may include nearby pointlike sources as well as stochastic backgrounds. We perform two directional searches for persistent GWs using data from the LIGO S5 science run: one optimized for pointlike sources and one for arbitrary extended sources. Finding no evidence to support the detection of GWs, we present 90% confidence level (C.L.) upper-limit maps of GW strain power with typical values between 2-20×10(-50) strain(2) Hz(-1) and 5-35×10(-49) strain(2) Hz(-1) sr(-1) for pointlike and extended sources, respectively. The latter result is the first of its kind. We also set 90% C.L. limits on the narrow-band root-mean-square GW strain from interesting targets including Sco X-1, SN 1987A and the Galactic center as low as ≈7×10(-25) in the most sensitive frequency range near 160 Hz.

In-vacuum Faraday isolation remote tuning.

In-vacuum Faraday isolators (FIs) are used in gravitational wave interferometers to prevent the disturbance caused by light reflected back to the input port from the interferometer itself. The efficiency of the optical isolation is becoming more critical with the increase of laser input power. An in-vacuum FI, used in a gravitational wave experiment (Virgo), has a 20 mm clear aperture and is illuminated by an almost 20 W incoming beam, having a diameter of about 5 mm. When going in vacuum at 10(-6) mbar, a degradation of the isolation exceeding 10 dB was observed. A remotely controlled system using a motorized lambda=2 waveplate inserted between the first polarizer and the Faraday rotator has proven its capability to restore the optical isolation to a value close to the one set up in air.

An upper limit on the stochastic gravitational-wave background of cosmological origin.

A stochastic background of gravitational waves is expected to arise from a superposition of a large number of unresolved gravitational-wave sources of astrophysical and cosmological origin. It should carry unique signatures from the earliest epochs in the evolution of the Universe, inaccessible to standard astrophysical observations. Direct measurements of the amplitude of this background are therefore of fundamental importance for understanding the evolution of the Universe when it was younger than one minute. Here we report limits on the amplitude of the stochastic gravitational-wave background using the data from a two-year science run of the Laser Interferometer Gravitational-wave Observatory (LIGO). Our result constrains the energy density of the stochastic gravitational-wave background normalized by the critical energy density of the Universe, in the frequency band around 100 Hz, to be <6.9 x 10(-6) at 95% confidence. The data rule out models of early Universe evolution with relatively large equation-of-state parameter, as well as cosmic (super)string models with relatively small string tension that are favoured in some string theory models. This search for the stochastic background improves on the indirect limits from Big Bang nucleosynthesis and cosmic microwave background at 100 Hz.

[Yeast anhydrobiosis: permeability of the cytoplasmic membrane]. / Angidrobioz drozhzhei pronitsaemost' tsitoplazmaticheskoi membrany.

When studying the dehydration effect of the eukaryotic cells on the structural and functional characteristics of the cytoplasmic membrane, it was established that serious rearrangements of its molecular organization showing up in a drastic increase in the permeability properties occurred in the yeast when the range of residual humidities of the order of 20-30% was reached. These changes were linked to the beginning of losing some bound water by the cells. It was shown that these rearrangements were reparable, and the normal membrane structure could be restored in the process of slow and gradual rehydration of dehydrated cells in the water vapors.

[Effect of dehydration of heat-induced restructuring of the cytoplasm membrane of yeast cells]. / Vliianie vysushivaniia na termoindutsirovannye strukturnye perestroiki tsitoplazmaticheskoi membrany kletok drozhzhei.

The effect of dehydration on the cytoplasmic membrane of yeast cells was studied using the method of spin labels. In the course of dehydration, the thermoinduced transition of lipids from the solid to a liquid-crystalline state was found to occur at a higher temperature as compared with native membranes.

[Stability to the extreme influences and significance of internal pH of Saccharomyces cerevisiae depending on the density of cellular suspensions]. / Ustoichivost' k ékstremal'nym vozdeistviiam i znachenie vnutrennego pH Saccharomyces cerevisiae v zavisimost ot plotnosti kletochnykh suspenzii.

The resistance of a Saccharomyces cerevisiae population against gamma-irradiation (400 krd), heating (60 degrees C), repeated freezing--thawing and rehydration of dehydrated cells was shown to depend on the density of a cell suspension. The percentage of damaged cells (stained with primulin) was found to increase in a suspension with decreasing cell concentrations. The effect was also exerted in an oxygen-free medium. The percentage of undamaged cells increased in populations with a lower cell concentration when a more viscous medium (0.2% agar) was used. The intracellular pH dropped down in a denser intact yeast suspension and rose with an increase in the concentration of dehydrated-rehydrated cells.

[Distribution of trehalose between the cells and the rehydration medium in dehydrated Saccharomyces cerevisiae]. / Raspredelenie tregalozy mezhdu kletkami i sredoi regidratatsii u obezvozhennykh Saccharomyces cerevisiae.

The work was concerned with studying the balance of trehalose distribution between the rehydration medium and Saccharomyces cerevisiae cells grown in a chemically defined medium and dehydrated using the convective technique. A direct linear correlation between the viability of populations and the overall residual trehalose content in the cells and in the medium after the rehydration of dry yeast cells was shown to be most important. An inverse correlation was established between the viability of yeast cells and the amount of trehalose mobilised by the cells in the process of rehydration.

[Degradation of ribonucleic acids in yeast cells during desiccation]. / O razrushenii ribonukleinovykh kislot v drozhzhevykh kletkakh pri ikh obezvozhivanii.

From 26 to 43% of RNA undergoes degradation in yeast cells when they pass into the state of anabiosis. Most of the degradation was found to occur at the first stage of cell dehydration when free water was removed from the cells. The mechanism of RNA degradation is supposed to involve enzyme-catalysed processes which are realised in the cell at the early stages of its dehydration.

[Lipid inclusions in cells and their changes during the desiccation and reactivation of yeast organisms]. / Lipidnye vkliucheniia v kletkakh i ikh izmeneniia pri obezvozhivaniia i reaktivatsii drozhzhevykh organizmov.

The formation of lipid granules in Saccharomyces cerevisiae cells was shown to begin in the exponential phase of the culture growth and to be associated with the activity of the endoplasmic reticulum. Lipid granules can be formed (1) when the endoplasmic reticulum cisterns extend and (2) when the endoplasmic reticulum membranes separate relatively small regions of the cell cytoplasm. Yeast cells contain spherosomes which differ in their structure. Lipid granules merge together upon dehydration of yeast cells. The authors discuss possible participation of these granules in the reparation of damages of the intracellular membranes.

[Effect of saccharose and lactose on the resistance of Saccharomyces cerevisiae yeast to desiccation]. / Vliianie sakharozy i laktozy na ustoichivost' drozhzhei Saccharomyces cerevisiae k obezvozhivaniiu.

Incubation of Saccharomyces cerevisiae cells in solutions containing different sucrose or lactose concentrations (0.25 to 1.0 M) makes the organism more resistant to dehydration. The effect is increased when the cells are incubated for longer periods of time. Apparently, certain intracellular reactions making the yeast survive upon dehydration are initiated under these conditions.

[Neurosensitization in resuscitated animals and its correction with piracetam]. / Neirosensibilizatsiia u reanimirovannykh zhivotnykh i ee korrektsiia piratsetamom.

Study of the immune reactions of the humoral and cellular types in rats, which had suffered terminal condition, has demonstrated the development of sensitization. The degree of the immunological shifts was determined by clinical death duration and by the period of postresuscitation. Injection of piracetam (100 mg/kg, subcutaneously) within the first 10 days after resuscitation noticeably reduced the manifestations of neurosensitization.

[Increased permeability of the intracellular membranes in the dehydration and rehydration of Saccharomyces cerevisiae yeasts]. / O povyshenii pronitsaemosti vnutrikletochnykh membran pri obezvozhivanii-regidratatsii drozhzhei Saccharomyces cerevisiae.

A considerable quantity of potassium and magnesium ions was found to be released from Saccharomyces cerevisiae cells being in the state of anabiosis upon their rehydration. The nearly maximal (for each of the experiments) quantity of ions was released as early as when cells dehydrated to a residual humidity of ca. 20% were rehydrated. A further decrease of the residual humidity down to 8-10% did not increase the leakage of the ions when the cells were rehydrated. It was concluded that the permeability of the cytoplasmic and vacuolar membranes for the ions increased when the cells were dehydrated and that this phenomenon should be attributed to the removal of free water from the cells.

[Protein yield in the rehydration of dehydrated Saccharomyces cerevisiae yeast cells]. / O vykhode belkov pri regidratatsii obezvozhennykh kletok drozhzhei Saccharomyces cerevisiae.

The release of proteins was studied during rehydration of Saccharomyces cerevisiae cells dehydrated using two techniques which were characterized by different survival rate. A correlation was established between the loss of proteins and the survival rate of cells after dehydration and rehydration. Proteins with a molecular mass from 6000 to 70,000 daltons (low molecular weight proteins predominating) were found in the rehydration medium by the method of disc-electrophoresis in polyacrylamide gel in the presence of sodium dodecylsulfate. Moreover, the rehydration medium exhibited the activity of certain phosphohydrolases and dehydrogenases; this finding suggests that proteins with a higher molecular weight are present in the medium.