901 research outputs found
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
Presence of atrial natriuretic factor in normal and hyperplastic human prostate and its relationship with oxytocin localisation
In this work, we showed the presence of atrial natriuretic factor (ANF) in human prostate and compared its localisation in normal and hyperplastic conditions. ANF was localised in epithelial and stromal cells, being increased in hyperplasia, mainly in the stromal component. Moreover, we compared ANF and oxytocin positivity in the same glands, focusing on the possible relationship between the paracrine effects of these two hormones
Polychlorinated biphenyls (PCBs) alter DNA methylation and genomic integrity of sheep fetal cells in a simplified in vitro model of pregnancy exposure
Polychlorinated biphenyls (PCBs) are persistent organic pollutants ubiquitously detectable in the environment
and in the food chain. Prenatal exposure to PCBs negatively affects fetal development and produces long-term
detrimental effects on child health. The present study sought to evaluate the cytotoxic and genotoxic effects of
chronic PCB exposure on fetal cells during pregnancy. To this aim, sheep embryonic fibroblasts (SEF) and
amniocytes (SA) were cultured in vitro in the presence of low doses of PCBs for a period of 120 days, comparable
to the full term of ovine pregnancy. Cellular proliferation rates, global DNA methylation, chromosome integrity,
and markers of DNA damage were evaluated at different time points. Moreover, SEF treated with PCBs for
60 days were left untreated for one further month and then examined in order to evaluate the reversibility of
PCB-induced epigenetic defects. PCB-treated SEF were more sensitive than SA treated with PCBs, in terms of low
cell proliferation, and increased DNA damage and global DNA methylation, which were still detectable after
interruption of PCB treatment. These data indicate that chronic exposure of fetal cells to PCBs causes permanent
genomic and epigenetic instability, which may influence both prenatal and post-natal growth up to adulthood.
Our in vitro model offer a simple and controlled means of studying the effects of different contaminants on fetal
cells - one that could set the stage for targeted in vivo studies
Controlled spermatozoa–oocyte interaction improves embryo quality in sheep
The current protocols of in vitro fertilization and culture in sheep rely on paradigms established more than 25 years ago, where Metaphase II oocytes are co-incubated with capacitated spermatozoa overnight. While this approach maximizes the number of fertilized oocytes, on the other side it exposes them to high concentration of reactive oxygen species (ROS) generated by active and degenerating spermatozoa, and positively correlates with polyspermy. Here we set up to precisely define the time frame during which spermatozoa effectively penetrates and fertilizes the oocyte, in order to drastically reduce spermatozoa-oocyte interaction. To do that, in vitro matured sheep oocytes co-incubated with spermatozoa in IVF medium were sampled every 30 min (start of incubation time 0) to verify the presence of a fertilizing spermatozoon. Having defined the fertilization time frame (4 h, data from 105 oocytes), we next compared the standard IVF procedures overnight (about 16 h spermatozoa/oocyte exposure, group o/nIVF) with a short one (4 h, group shIVF). A lower polyspermic fertilization (> 2PN) was detected in shIVF (6.5%) compared to o/nIVF (17.8%), P < 0.05. The o/nIVF group resulted in a significantly lower 2-cell stage embryos, than shIVF [34.6% (81/234) vs 50.6% (122/241) respectively, P < 0.001]. Likewise, the development to blastocyst stage confirmed a better quality [29% (70/241) vs 23.5% (55/234), shIVF vs o/nIVF respectively] and an increased Total Cell Number (TCN) in shIVF embryos, compared with o/n ones. The data on ROS have confirmed that its generation is IVF time-dependent, with high levels in the o/nIVF group. Overall, the data suggest that a shorter oocyte-spermatozoa incubation results in an improved embryo production and a better embryo quality, very likely as a consequence of a shorter exposure to the free oxygen radicals and the ensuing oxidative stress imposed by overnight culture
L’ambiente marino costiero: aspetti e tutela. Progetto formativo di Alternanza Scuola Lavoro 2016‐2019 Liceo Scienze Applicate
Il percorso formativo consente di acquisire nozioni teoriche e pratiche sulle moderne tecniche (strumentali e metodologiche) di investigazione del “datum” geologico finalizzate allo studio multidisciplinare dell’ambiente marino‐costiero, con particolare riguardo alle ricerche sperimentali che l’Istituto IAMC ha condotto e conduce nel Golfo di Napoli.
Vengono trattate anche tematiche di gestione del sistema sicurezza e qualità con particolare riguardo alle attività lavorative di ricerca (acquisizione, elaborazione e restituzione del dato),nonché indicazioni di procedure gestionali di progetto finalizzate al corretto utilizzo della risorsa umana e strumentale
Wharton’s Jelly Mesenchymal Stromal Cells Support the Expansion of Cord Blood–derived CD34 + Cells Mimicking a Hematopoietic Niche in a Direct Cell–cell Contact Culture System
Wharton’s jelly mesenchymal stromal cells (WJ-MSCs) have been recently exploited as a feeder layer in coculture systems to expand umbilical cord blood–hematopoietic stem/progenitor cells (UCB-HSPCs). Here, we investigated the role of WJ-MSCs in supporting ex vivo UCB-HSPC expansion either when cultured in direct contact (DC) with WJ-MSCs or separated by a transwell system or in the presence of WJ-MSC–conditioned medium. We found, in short-term culture, a greater degree of expansion of UCB-CD34 + cells in a DC system (15.7 ± 4.1-fold increase) with respect to the other conditions. Moreover, in DC, we evidenced two different CD34 + cell populations (one floating and one adherent to WJ-MSCs) with different phenotypic and functional characteristics. Both multipotent CD34 + /CD38 − and lineage-committed CD34 + /CD38 + hematopoietic progenitors were expanded in a DC system. The former were significantly more represented in the adherent cell fraction than in the floating one (18.7 ± 11.2% vs. 9.7 ± 7.9% over the total CD34 + cells). Short-term colony forming unit (CFU) assays showed that HSPCs adherent to the stromal layer were able to generate a higher frequency of immature colonies (CFU-granulocyte/macrophage and burst-forming unit erythroid/large colonies) with respect to the floating cells. In the attempt to identify molecules that may play a role in supporting the observed ex vivo HSPC growth, we performed secretome analyses. We found a number of proteins involved in the HSPC homing, self-renewal, and differentiation in all tested conditions. It is important to note that a set of sixteen proteins, which are only in part reported to be expressed in any hematopoietic niche, were exclusively found in the DC system secretome. In conclusion, WJ-MSCs allowed a significant ex vivo expansion of multipotent as well as committed HSPCs. This may be relevant for future clinical applications
Dipolar degrees of freedom and Isospin equilibration processes in Heavy Ion collisions
Background: In heavy ion collision at the Fermi energies Isospin
equilibration processes occur- ring when nuclei with different charge/mass
asymmetries interacts have been investigated to get information on the
nucleon-nucleon Iso-vectorial effective interaction. Purpose: In this paper,
for the system 48Ca +27 Al at 40 MeV/nucleon, we investigate on this process by
means of an observable tightly linked to isospin equilibration processes and
sensitive in exclusive way to the dynamical stage of the collision. From the
comparison with dynamical model calculations we want also to obtain information
on the Iso-vectorial effective microscopic interaction. Method: The average
time derivative of the total dipole associated to the relative motion of all
emitted charged particles and fragments has been determined from the measured
charges and velocities by using the 4? multi-detector CHIMERA. The average has
been determined for semi- peripheral collisions and for different charges Zb of
the biggest produced fragment. Experimental evidences collected for the systems
27Al+48Ca and 27Al+40Ca at 40 MeV/nucleon used to support this novel method of
investigation are also discussed.Comment: Submitted for publication on Phys. Rev. C. 0n 24-oct-201
Unsuspected Involvement of Spinal Cord in Alzheimer Disease
OBJECTIVE: Brain atrophy is an established biomarker for dementia, yet spinal cord involvement has not been investigated to date. As the spinal cord is relaying sensorimotor control signals from the cortex to the peripheral nervous system and vice-versa, it is indeed a very interesting question to assess whether it is affected by atrophy due to a disease that is known for its involvement of cognitive domains first and foremost, with motor symptoms being clinically assessed too. We, therefore, hypothesize that in Alzheimer’s disease (AD), severe atrophy can affect the spinal cord too and that spinal cord atrophy is indeed an important in vivo imaging biomarker contributing to understanding neurodegeneration associated with dementia.
METHODS: 3DT1 images of 31 AD and 35 healthy control (HC) subjects were processed to calculate volume of brain structures and cross-sectional area (CSA) and volume (CSV) of the cervical cord [per vertebra as well as the C2-C3 pair (CSA23 and CSV23)]. Correlated features (ρ > 0.7) were removed, and the best subset identified for patients’ classification with the Random Forest algorithm. General linear model regression was used to find significant differences between groups (p ≤ 0.05). Linear regression was implemented to assess the explained variance of the Mini-Mental State Examination (MMSE) score as a dependent variable with the best features as predictors.
RESULTS: Spinal cord features were significantly reduced in AD, independently of brain volumes. Patients classification reached 76% accuracy when including CSA23 together with volumes of hippocampi, left amygdala, white and gray matter, with 74% sensitivity and 78% specificity. CSA23 alone explained 13% of MMSE variance.
DISCUSSION: Our findings reveal that C2-C3 spinal cord atrophy contributes to discriminate AD from HC, together with more established features. The results show that CSA23, calculated from the same 3DT1 scan as all other brain volumes (including right and left hippocampi), has a considerable weight in classification tasks warranting further investigations. Together with recent studies revealing that AD atrophy is spread beyond the temporal lobes, our result adds the spinal cord to a number of unsuspected regions involved in the disease. Interestingly, spinal cord atrophy explains also cognitive scores, which could significantly impact how we model sensorimotor control in degenerative diseases with a primary cognitive domain involvement. Prospective studies should be purposely designed to understand the mechanisms of atrophy and the role of the spinal cord in AD
IL-17 and its role in inflammatory, autoimmune, and oncological skin diseases. State of art
Recent data support the theory of the involvement of IL-17 in the pathogenesis of several chronic inflammatory skin diseases (psoriasis, atopic dermatitis, acne, hidradenitis suppurativa) and autoimmune skin diseases (alopecia areata, vitiligo, bullous diseases). Even if the role of IL-17 in inflammatory and autoimmune diseases has been reported extensively, its role in tumor is still controversial. Some reports show that Th17 cells eradicate tumors, while others reveal that they promote the initiation and early growth of tumors. Herein, we review the role of IL-17 in the involvement of some common dermatologic diseases: psoriasis, atopic dermatitis, hidradenitis suppurativa, acne, vitiligo, melanoma, and nonmelanoma skin cancers
Therapeutic options for the treatment of actinic keratosis with scalp and face localization
Actinic keratosis (AK) is a common skin disease related to ultraviolet chronic exposure, that is now considered a squamous cell carcinoma in situ. Primary skin cancer prevention strategies should be recommended for high risk patients. There is a wide spectrum of treatment options available for AKs, and several variables should be taken into account regarding the best therapeutic choice for each patient. The purpose of this article is to review the current treatment strategies for AKs localized on the face and scalp, with a focus on the practical point of view that could be useful for choosing the best therapeutic option. The two main therapeutic approaches will be distinguished first: lesion-directed and field-directed. Afterwards, the treatment based on clinical type and patient comorbidity will be discusse
- …