972 research outputs found
Perinatal stem cells revisited: directions and indications at the crossroads between tissue regeneration and repair.
Perinatal stem cells research attracted great interest worldwide in recent years. Foetus-associated tissues contain
various populations of stem cells, most of which are comprised within the category of mesenchymal stem cells
(MSCs). This special issue collects both reviews and original
reports on all the perinatal stem cell types which are currently under investigation. These cells have multiple promising features: differentiative capacity towards mature cell
types of all the three germ layers, hypoimmunogenicity in
vitro and in vivo, ease of sourcing, ex vivo culture and stor-
age. In particular, immune modulation is viewed as a prom-
ising feature of many MSCs populations, since these cells,
once administered therapeutically, may be able to overcome,
or at least evade, the host immune response which may lead
to acute or chronic rejection of the transplant
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A laser-scanning confocal microscopy study of carrageenan in red algae from seaweed farms near the Caribbean entrance of the Panama Canal
Kappaphycus alvarezii (Doty) Doty ex P.C. Silva, a red macroalga, is a commercial source of carrageenan, a widely used polysaccharide compound important in the food and pharmaceutical industries, in nanotechnology, and in pharmacological applications. Carrageenan is found mainly in the cell wall and in the intercellular matrix. This is the first study to propose the characterization of carrageenans in vitro, using the auto-fluorescence properties of the alga treated with different polyamines: putrescine, spermidine, and spermine. This study suggests a four-phase cultivation sequence for seaweed farmers to enhance and assess the potential carrageenan yield of their crops. In phase 1, seedlings were treated with each of the polyamines. Explants were subsequently transferred through two additional culture phases before being planted on the sea farms in phase 4 and then harvested after 60 days for analysis. Images from transverse sections of 11 representative cultured K. alvarezii samples were obtained at 561 nm excitation wavelength for both the cell center and the cell wall of each sample. Spectral data were also analyzed using the spectral phasor algorithm of SimFCS developed at the Laboratory for Fluorescence Dynamics (www.lfd.uci.edu). We report on the identification of several spectral fluorescence emission fingerprints from different auto-fluorescence compounds spatially mapped using this technique. These fingerprints have the potential to improve strain selection of explants for enhanced carrageenan yield in seaweed farming operations as well as to enable wholesale pricing to correspond with crop quality
School readiness of moderately preterm children at preschool age
The study investigates the preschool readiness of moderately preterm children and, in particular, the likely presence of learning disabilities at preschool age. Its theoretical model detects linguistic comprehension and expression; memory-related metacognition and cognition skills; orientation and motor coordination skills; premathematics and preliteracy ones. The research project involved an experimental group made up of 55 moderately preterm children (mean age = 62 months, mean gestational age = 34.6 weeks), without any clinical neonatal complications, and low birth weight (M = 2,100 g, SD = 350 g); a control group made up of 55 full-term children without pre- and perinatal complications. The children’s primary school reference teachers were given a questionnaire (Observative Questionnaire for Early Identification of Learning Disabilities), which was aimed at identifying any likely social and cognitive skill deficits at preschool age. The data, submitted to nonparametric univariate variance, show how scores of moderately preterm children in the metacognition [U (n1 e n2 = 55) = 35, p = 0.04, r = 0.49] are statistically lower, other cognitive skills (memory, orientation, and visual–motor coordination) [U (n1 e n2 = 55) = 32, p = 0.02, r = 0.45], premathematics [U (n1 e n2 = 55) = 32, p = 0.02, r = 0.44], and the total score [U (n1 e n2 = 55) = 31, p = 0.02, r = 0.12]. Such data would seem to suggest the need for hypothesizing preventive training and educational paths as a prerequisite for the development of the school abilities
Ten kilodalton heat shock protein (HSP10) is overexpressed during carcinogenesis of large bowel and uterine exocervix
In the present study, we evaluated the presence and the level of expression of HSP10 in two carcinogenetic models: the 'adenoma-carcinoma sequence' of large bowel and the 'dysplasia-carcinoma sequence' of uterine exocervix. We found HSP10 was overexpressed during the carcinogenesis of both organs. In particular, HSP10 was overexpressed early in large bowel carcinogenesis, while the expression of this protein in exocervical carcinogenesis gradually increased from normal through dysplastic to neoplastic tissues. The quantitative analysis of immunohistochemistry and the Western blotting confirmed these results. Our previous observations showed overexpression of HSP60 in the same carcinogenetic models. This report correlates the overexpression of HSP10 with that of HSP60 during carcinogenesis in vivo. These results could stimulate further studies on the pathogenetic role of these proteins during the carcinogenesis as well as their use as diagnostic and prognostic tools in oncology. \ua9 2003 Elsevier Science Ltd. All rights reserved
Dermoscopy and methyl aminolevulinate: A study for detection and evaluation of field cancerization
Actinic keratosis (AK) is a keratinocyte intraepidermal neoplasia UV light
–
induced that frequently appears in
sun-exposed areas of the skin. Although historically AK was de
fi
ned as
“
precancerous
”
, actually it is considered
as the earliest stage of squamous cell carcinoma (SCC) in situ. Since AKs can progress into invasive SCC, their
treatment isrecommended. AKsrarely developasa singlelesion;usually multiplelesions commonly affect anen-
tire area of chronically actinic damaged skin. This has led to the concept of
“
fi
eld cancerization
”
, an area chroni-
cally sun-exposed that surrounds peripherally visible lesions, in which are individualized subclinical alterations.
One of the main principles endpoint in the management of AKs is the evaluation and the treatment of
fi
eld
cancerization. In this view, in order to detect and quantify
fi
eld cancerization, we employed a method based
on the topical application of methyl aminolevulinate (MAL) and the detection of the
fl
uorescence emitted by
its metabolite Protoporphyrin IX (PpIX); then, considering the extension and the intensity of measured
fl
uores-
cence, we create a score of
fi
eld cancerization. The results show that patients underwent to daylight PDT had a
reduction of total score, from T0 to T2. Whereas in the group untreated we observed a stability of total score or
a slightly worse. So, the method and the score used allows to evaluate with a good approximation the dimension
of
fi
eld cancerization and show the modi
fi
cation of it after treatment
Free and open-source control software for 3-D motion and processing
RepRap 3-D printers and their derivatives using conventional firmware are limited by: 1) requiring technical knowledge, 2) poor resilience with unreliable hardware, and 3) poor integration in complicated systems. In this paper, a new control system called Franklin, for CNC machines in general and 3-D printers specifically, is presented that enables web-based three dimensional control of additive, subtractive and analytical tools from any Internet connected device. Franklin can be set up and controlled entirely from a web interface; it uses a custom protocol which allows it to continue printing when the connection is temporarily lost, and allows communication with scripts
Multiparametric advanced research tool for meteo satellites data interfacing with space observation of ultra high energy cosmic rays
To approach the study of the cosmic rays in the energy range
E > 1020 eV, the upper end of the spectrum observed to date, with a large statistical significance (103 events/year), and hence address the solution of several
astrophysical and cosmological problems related to their existence and behaviour, a new generation of experiments will probably have to be conceived and realised. They will be based on the observation and measurements of cosmic rays from space. The extremely low rate of these events (∼ 1 event/(century × km2 × sr)) imposes a very large effective area to be monitored, of the order of 105 km2, as an observational requirement to meet the target statistics. The Extreme Universe Space Observatory (EUSO)mission has been proposed as the precursor of this new generation of experiments. Its approach consists in fact in looking downwards to the Earth atmosphere by means of a large
field-of-view telescope accommodated aboard an orbiting satellite. The fluorescence strike produced by a cosmic ray through the atmosphere will be recorded by the detector, which will reconstruct the kinematical and dynamical features of the primary cosmic ray. The atmosphere acts therefore as an active target for the detectable event. A strategic tool for the success of EUSO as well as for all the experiments of its category will be a correct and detailed atmospheric sounding system, in order to monitor the atmospheric parameters within the field-of-view of the telescope. Beside an on-board measurement by means of dedicated devices such an infrared camera (IR)and possibly a LIDAR (LIght Detection And Ranging)coupled to the main instrument, the Atmosphere Sounding will take advantage from the continuous observation of the atmospheric parameters given by the orbiting meteorological satellites. Their databases have thus to be interfaced to the experimental data and used picking-up the relevant data according to the space and time coordinates corresponding
to each triggered event. The present work outlines a software module (MARVIN-Multiparametric Advanced Research tool for Visualisation In the Network) able to build-up such an interface, and shows a preliminary implementation
of it, using a sample of existing satellites and ISCCP meteorological data collection. It has been developed during the phase A study of the EUSO mission but is general
enough to be adapted to different missions observing the Earth atmosphere from space
Thoracoscopy in pleural effusion –two techniques: awake single-access video-assisted thoracic surgery versus 2-ports video-assisted thoracic surgery under general anesthesia
Awake single access video-assisted thoracic surgery with local anesthesia improves procedure tolerance, reduces postoperative stay and costs.
MATERIALS & METHODS: Local anesthesia was made with lidocaine and ropivacaine. We realize one 20 mm incision for the 'single-access', and two incisions for the '2-trocars technique'.
RESULTS: Mortality rate was 0% in both groups. Postoperative stay: 3dd ± 4 versus 4dd ± 5, mean operative time: 39 min versus 37 min (p < 0.05). Chest tube duration: 2dd ± 5 versus 3dd ± 6.
COMPLICATIONS: 11/95 versus 10/79.
CONCLUSION: Awake technique reduce postoperative hospital stay and chest drainage duration, similar complications and recurrence rate. The authors can say that 'awake single-access VATS' is an optimal diagnostic and therapeutic tool for the management of pleural effusions, but above extends surgical indication to high-risk patients
Determination of the photodisintegration reaction rates involving charged particles: systematical calculations and proposed measurements based on Extreme Light Infrastructure - Nuclear Physics (ELI-NP)
Photodisintegration reaction rates involving charged particles are of
relevance to the p-process nucleosynthesis that aims at explaining the
production of the stable neutron-deficient nuclides heavier than iron. In this
study, the cross sections and astrophysical rates of (g,p) and (g,a) reactions
for about 3000 target nuclei with 10<Z<100 ranging from stable to proton
dripline nuclei are computed. To study the sensitivity of the calculations to
the optical model potentials (OMPs), both the phenomenological Woods-Saxon and
the microscopic folding OMPs are taken into account. The systematic comparisons
show that the reaction rates, especially for the (g,a) reaction, are
dramatically influenced by the OMPs. Thus the better determination of the OMP
is crucial to reduce the uncertainties of the photodisintegration reaction
rates involving charged particles. Meanwhile, a gamma-beam facility at ELI-NP
is being developed, which will open new opportunities to experimentally study
the photodisintegration reactions of astrophysics interest. Considering both
the important reactions identified by the nucleosynthesis studies and the
purpose of complementing the experimental results for the reactions involving
p-nuclei, the measurements of six (g,p) and eight (g,a) reactions based on the
gamma-beam facility at ELI-NP and the ELISSA detector for the charged particles
detection are proposed, and the GEANT4 simulations are correspondingly
performed. The minimum required energies of the gamma-beam to measure these
reactions are estimated. It is shown that the direct measurements of these
photonuclear reactions within the Gamow windows at T_9=2.5 for p-process are
fairly feasible and promising at ELI-NP. The expected experimental results will
be used to constrain the OMPs of the charged particles, which can eventually
reduce the uncertainties of the reaction rates for the p-process
nucleosynthesis.Comment: 14 pages, 8 figures, Phys. Rev. C accepte
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