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1.
Materials (Basel) ; 17(8)2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38673077

RESUMEN

The laser surface texturing (LST) technique has recently been used to enhance adhesion bond strength in various coating applications and to create structures with controlled hydrophobic or superhydrophobic surfaces. The texturing processing parameters can be adjusted to tune the surface's polarity, thereby controlling the ratio between the polar and dispersed components of the surface free energy and determining its hydrophobic character. The aim of this work is to systematically select appropriate laser and scan head parameters for high-quality surface topography of metal-based materials. A correlation between texturing parameters and wetting properties was made in view of several technological applications, i.e., for the proper growth of conformal layers onto laser-textured metal surfaces. Surface analyses, carried out by scanning electron microscopy and profilometry, reveal the presence of periodic microchannels decorated with laser-induced periodic surface structures (LIPSS) in the direction parallel to the microchannels. The water contact angle varies widely from about 20° to 100°, depending on the treated material (titanium, nickel, etc.). Nowadays, reducing the wettability transition time from hydrophilicity to hydrophobicity, while also changing environmental conditions, remains a challenge. Therefore, the characteristics of environmental dust and its influence on the properties of the picosecond laser-textured surface (e.g., chemical bonding of samples) have been studied while monitoring ambient conditions.

2.
Mar Genomics ; 63: 100951, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35395504

RESUMEN

In this paper, we identify some sponge specimens collected in the Faro Lake in Sicily, and belonging to Haliclona (Halicoclona) by using morphological analysis accompanied by molecular analysis through amplification of several molecular markers (18S and 28S rRNA, CO1 and ITS). The samples are identified as. H. (Halichoclona) vansoesti de Weerdt, de Kluijver & Gómez, 1999, a species native to the Caribbean, and therefore this is the first record of an alien species of the Demospongiae class (Porifera) from the Mediterranean Sea. This presence can be ascribed as results of global change (mainly global warming) that are affecting marine environment.


Asunto(s)
Haliclona , Poríferos , Animales , Región del Caribe , Haliclona/anatomía & histología , Haliclona/genética , Especies Introducidas , Mar Mediterráneo , Poríferos/genética
3.
Entropy (Basel) ; 24(3)2022 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-35327929

RESUMEN

We reconsider model II of Orban et al. (J. Chem. Phys. 1968, 49, 1778−1783), a two-dimensional lattice-gas system featuring a crystalline phase and two distinct fluid phases (liquid and vapor). In this system, a particle prevents other particles from occupying sites up to third neighbors on the square lattice, while attracting (with decreasing strength) particles sitting at fourth- or fifth-neighbor sites. To make the model more realistic, we assume a finite repulsion at third-neighbor distance, with the result that a second crystalline phase appears at higher pressures. However, the similarity with real-world substances is only partial: Upon closer inspection, the alleged liquid−vapor transition turns out to be a continuous (albeit sharp) crossover, even near the putative triple point. Closer to the standard picture is instead the freezing transition, as we show by computing the free-energy barrier relative to crystal nucleation from the "liquid".

4.
Zootaxa ; 4790(2): zootaxa.4790.2.13, 2020 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-33055850

RESUMEN

The use of SCUBA diving for marine research in the Chilean fjords has increased the possibility of obtaining information on the sponge assemblages living in this environment. However, much work is still needed to achieve a satisfactory knowledge of the benthos of this wide region. As to sponges, just consider that seventeen new species have been recently described by several authors (Hajdu et al., 2013; Fernandez et al., 2016; Bertolino et al., 2019) with detailed information of this benthic fauna for this area. Aim of this work is the description of a new species of Acanthella (Dictyonellidae van Soest, Diaz Pomponi, 1990), Acanthella danerii sp. nov.. It was collected at "Seno Magdalena" (44°61'48.63" S 72°95'83.12" W) (Chilean fjords) by SCUBA, at 20 m depth, on hard substrates of a vertical wall ending on a rocky bottom that slopes down to 32 m during a survey in August 2016.


Asunto(s)
Poríferos , Animales , Chile , Estuarios , Océano Pacífico
5.
Zootaxa ; 4674(3): zootaxa.4674.3.9, 2019 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-31716008

RESUMEN

The use of ROVs has greatly enhanced the possibility of obtaining information on living deep sponge communities (Bertolino et al. 2015). The aim of this work is to describe a new Mediterranean species, Antho (Plocamia) sarasiri sp. nov. (Microcionidae Carter, 1875), characterized by dumbbell spicules making up the framework of the choanosomal skeleton (Van Soest et al. 2013). Samples were collected by ROV during an oceanographic survey in September 2012 on board of the R/V 'Astrea' (ISPRA) in "Secca P.ta Fetovaia" (42°43'29.54"N 10° 9'31.64"E) (Elba Island, Tyrrhenian Sea) at 70 m depth. We compared our sample with additional material collected by Sarà Siribelli (1960, 1962).


Asunto(s)
Poríferos , Animales , Islas
6.
Zootaxa ; 4623(2): zootaxa.4623.2.5, 2019 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-31716262

RESUMEN

The presence of fjords, islands and channels originating from glacial erosion and ice cap retreat, makes the Chilean benthic biodiversity difficult to explore and study. Our survey of this region allowed the identification of 29 Demospongiae species in total. Two of them are new to science and here described: Biemna lutea sp. nov., and Hamigera cleistochela sp. nov.. Two species (Clathria (Clathria) microxa and Lissodendoryx (Ectyodoryx) patagonica,) are new for the region and the Chilean fjords. Lissodendoryx (Ectyodoryx) patagonica was found for the second time after the original description by Ridley Dendy, 132 years ago. These results - considering the small number of species identified on the whole - are promising and confirm that the marine biodiversity of Chilean fjords is remarkable but not well known yet.


Asunto(s)
Poríferos , Animales , Biodiversidad , Chile , Ecosistema , Estuarios , Islas
7.
J Exp Biol ; 222(Pt 17)2019 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-31371401

RESUMEN

Tissue repair is an adaptive and widespread metazoan response. It is characterised by different cellular mechanisms and complex signalling networks that involve numerous growth factors and cytokines. In higher animals, transforming growth factor-ß (TGF-ß) signalling plays a fundamental role in wound healing. In order to evaluate the involvement of TGF superfamily members in lower invertebrate tissue regeneration, sequences for putative TGF ligands and receptors were isolated from the transcriptome of the marine sponge Chondrosia reniformis We identified seven transcripts that coded for TGF superfamily ligands and three for TGF superfamily receptors. Phylogenetically, C. reniformis TGF ligands were not grouped into any TGF superfamily clades and thus presumably evolved independently, whereas the TGF receptors clustered in the Type I receptor group. We performed gene expression profiling of these transcripts in sponge regenerating tissue explants. Data showed that three ligands (TGF1, TGF3 and TGF6) were mainly expressed during early regeneration and seemed to be involved in stem cell maintenance, whereas two others (TGF4 and TGF5) were strongly upregulated during late regeneration and thus were considered pro-differentiating factors. The presence of a strong TGF inhibitor, SB431542, blocked the restoration of the exopinacoderm layer in the sponge explants, confirming the functional involvement of the TGF pathway in tissue regeneration in these early evolved animals.


Asunto(s)
Familia de Multigenes/fisiología , Poríferos/fisiología , Regeneración/genética , Factores de Crecimiento Transformadores/genética , Animales , Perfilación de la Expresión Génica , Factores de Crecimiento Transformadores/metabolismo
8.
Mar Drugs ; 16(4)2018 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-29596370

RESUMEN

Collagen is involved in the formation of complex fibrillar networks, providing the structural integrity of tissues. Its low immunogenicity and mechanical properties make this molecule a biomaterial that is extremely suitable for tissue engineering and regenerative medicine (TERM) strategies in human health issues. Here, for the first time, we performed a thorough screening of four different methods to obtain sponge collagenous fibrillar suspensions (FSs) from C. reniformis demosponge, which were then chemically, physically, and biologically characterized, in terms of protein, collagen, and glycosaminoglycans content, viscous properties, biocompatibility, and antioxidant activity. These four FSs were then tested for their capability to generate crosslinked or not thin sponge collagenous membranes (SCMs) that are suitable for TERM purposes. Two types of FSs, of the four tested, were able to generate SCMs, either from crosslinking or not, and showed good mechanical properties, enzymatic degradation resistance, water binding capacity, antioxidant activity, and biocompatibility on both fibroblast and keratinocyte cell cultures. Finally, our results demonstrate that it is possible to adapt the extraction procedure in order to alternatively improve the mechanical properties or the antioxidant performances of the derived biomaterial, depending on the application requirements, thanks to the versatility of C. reniformis extracellular matrix extracts.


Asunto(s)
Materiales Biocompatibles , Colágeno/química , Ensayo de Materiales , Poríferos/química , Animales , Compuestos de Bifenilo , Depuradores de Radicales Libres , Membranas Artificiales , Microscopía Electrónica de Rastreo , Picratos
9.
PLoS One ; 12(5): e0177945, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28531209

RESUMEN

This paper concerns the changes occurred over both decennial and millennial spans of time in a sponge assemblage present in coralligenous biogenic build-ups growing at 15 m depth in the Ligurian Sea (Western Mediterranean). The comparison of the sponge diversity after a time interval of about 40 years (1973-2014) showed a significant reduction in species richness (about 45%). This decrease affected mainly the massive/erect sponges, and in particular the subclass Keratosa, with a species loss of 67%, while the encrusting and cavity dwelling sponges lost the 36% and 50%, respectively. The boring sponges lost only one species (25%). This changing pattern suggested that the inner habitat of the bioconstructions was less affected by the variations of the environmental conditions or by the human pressures which, on the contrary, strongly affected the species living on the surface of the biogenic build-ups. Five cores extracted from the bioherms, dating back to 3500 YBP, allowed to analyse the siliceous spicules remained trapped in them in order to obtain taxonomic information. Changes at generic level in diversity and abundance were observed at 500/250-years intervals, ranging between 19 and 33 genera. The number of genera showed a sharp decrease since 3500-3000 to 3000-2500 YBP. After this period, the genera regularly increased until 1500-1250 YBP, from when they progressively decreased until 1000-500 YBP. Tentatively, these changes could be related to the different climatic periods that followed one another in the Mediterranean area within the considered time span. The recent depletion in sponge richness recorded in the Ligurian coralligenous can be considered relevant. In fact, the analysis of the spicules indicated that the sponges living in these coralligenous habitats remained enough stable during 3000 years, but could have lost a significant part of their biodiversity in the last decades, coinciding with a series of warming episodes.


Asunto(s)
Poríferos/fisiología , Animales , Biodiversidad , Arrecifes de Coral , Monitoreo del Ambiente , Humanos , Mar Mediterráneo , Análisis Espacio-Temporal
10.
GED gastroenterol. endosc. dig ; 35(4): 162-165, out.-dez. 2016. ilus
Artículo en Portugués | LILACS | ID: biblio-832654

RESUMEN

Os tumores carcinoides gástricos são neoplasias raras, derivadas das células enterocromafins e podem associar-se a doenças inflamatórias intestinais, como a doença de Crohn. Atualmente, há aumento da incidência devido a maior realização de endoscopia digestiva alta. A abordagem depende do tipo, tamanho e número de lesões, além da presença de metástases. Este é o relato de caso de um paciente com doença de Crohn associada a tumor carcinoide gástrico.


The gastric carcinoid tumors are rare, derived from the enterochromaffin cells and may be associated with inflammatory bowel diseases such as Crohns disease. Currently, there is increased incidence due to higher performing endoscopy. The approach depends on the type, size, number of lesions and the presence of metastases. This is a case report of a patient with Crohns disease associated with gastric carcinoid tumor.


Asunto(s)
Humanos , Masculino , Adulto , Neoplasias Gástricas , Tumor Carcinoide , Enfermedad de Crohn , Tumores Neuroendocrinos , Endoscopía del Sistema Digestivo
11.
Rev. bras. ter. intensiva ; 21(1): 1-8, jan.-mar. 2009. graf, tab
Artículo en Portugués | LILACS | ID: lil-572663

RESUMEN

OBJETIVO: Os idosos constituem uma população com características próprias e freqüentes admissões em unidades de terapia intensiva. O presente estudo teve por objetivo avaliar a capacidade de predizer a sobrevida desses pacientes através dos índices APACHE II, UNICAMP II, SAPS II e SAPS 3 equações global e América Central/Sul. MÉTODOS: Foram incluídos pacientes idosos admitidos no período de 01/01/2006 a 31/12/2006, definidos como idade > 60 anos. Foram excluídos aqueles reinternados. Nos pacientes restantes, analisou-se a taxa de letalidade padronizada, a calibração e a discriminação para cada índice. O evento avaliado foi óbito ou alta hospitalar. RESULTADOS: Foram admitidos na UTI 386pacientesidosos,sendo36excluidospor reinternações, restando 350 para análise. A taxa de letalidade padronizada aproximouse da unidade em todos os índices, exceto no SAPS II (TLP=1,5455) que subestimou a letalidade. A calibração, por meio dos testes de Hosmer-Lemeshow, foi inadequada (p < 0,05), exceto para o UNICAMP II (p > 0,5). Na curva de calibração, os modelos se afastaram da linha ideal. Todos mostraram excelente discriminação por meio da área sob curva recebedora das características dos operadores ( > 0,8). CONCLUSÕES: Na população estudada, os modelos apresentaram excelente discriminação e calibração inadequada. O SAPS II subestimou a letalidade.


OBJECTIVE: The elderly constitute a population with their own features and frequent admissions in intensive care units. This study has the objective to evaluate the ability to predict the survival of these patients through the APACHE II, UNICAMP II, SAPS II and SAPS 3 indexes, global and Central America/South equations. METHODS: Elderly patients admitted from 01/01/2006 to 12/3/2006, defined as age > 60 years, were included in this study. Those who were readmitted were excluded. The rate of lethality standardized, calibration and discrimination for each index in the remaining patients were analysed. The outcome were death or hospital discharge. RESULTS: Three hundred eighty six elderly patients were included in this study, being 36 excluded by readmission, remaining 350 for analysis. The rate of lethality standardized came near to the unit in all indexes, except the SAPS II (TLP=1.5455) which underestimated the lethality. The calibration, via Hosmer-Lemeshow tests was inadequate (p < 0.05), except for the UNICAMP II (p > 0.5). On the calibration curve, the models have distanced themselves from the pattern line. All of them presented an excellent discrimination via receiver operating characteristics curves (> 0.8). CONCLUSIONS: In the studied population, the models presented an excellent discrimination and inadequate calibration. SAPS II underestimated the lethality.

12.
Rev Bras Ter Intensiva ; 21(1): 1-8, 2009 Mar.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-25303122

RESUMEN

OBJECTIVE: The elderly constitute a population with their own features and frequent admissions in intensive care units. This study has the objective to evaluate the ability to predict the survival of these patients through the APACHE II, UNICAMP II, SAPS II and SAPS 3 indexes, global and Central America/South equations. METHODS: Elderly patients admitted from 01/01/2006 to 12/3/2006, defined as age > 60 years, were included in this study. Those who were readmitted were excluded. The rate of lethality standardized, calibration and discrimination for each index in the remaining patients were analysed. The outcome were death or hospital discharge. RESULTS: Three hundred eighty six elderly patients were included in this study, being 36 excluded by readmission, remaining 350 for analysis. The rate of lethality standardized came near to the unit in all indexes, except the SAPS II (TLP=1.5455) which underestimated the lethality. The calibration, via Hosmer-Lemeshow tests was inadequate (p < 0.05), except for the UNICAMP II (p > 0.5). On the calibration curve, the models have distanced themselves from the pattern line. All of them presented an excellent discrimination via receiver operating characteristics curves (> 0.8). CONCLUSIONS: In the studied population, the models presented an excellent discrimination and inadequate calibration. SAPS II underestimated the lethality.

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