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131.
Nowadays, laser scalpels are commonly used in surgery, replacing the traditional surgical scalpels for several applications involving cutting or ablating living biological tissue. Laser scalpels are generally used to concentrate light energy in a very small‐sized area; light energy is then converted in heat by the tissues. In other cases, the fiber glass tip of the laser scalpel is heated to high temperature and used to cut the tissues. Depending on the temperature reached in the irradiated area, different effects are visible in the tissues. In this study, we report the discovery and characterization of the light emitted by soft mammalian biological tissues from seconds to hours after laser surgery application. A laser diode (with hot fiber glass tip) working at 808 nm and commercially available for medical and dentistry applications was used. The irradiated tissues (red meat, chicken breast and fat) showed light emission in the visible range, well detectable with a commercial charge coupled device (CCD) camera. The time decay of the light emission, the laser power effects and the spectral features in the range 500 to 840 nm in the different tissues are here reported.   相似文献   
132.
133.
The secondary metabolite profiles of microfungi of the genus Penicillium isolated from samples of grape berries collected in two different phases during two vegetative seasons in Slovakia is described to assess the taxonomy. Three Slovak vine regions have been selected for this study, based on their climatic differences and national economic importance. Cultures of microfungi isolated from berries were incubated on different selective media for macro and micromorphology identification. The species Penicillium brevicompactum, Penicillium crustosum, Penicillium chrysogenum, Penicillium expansum, Penicillium palitans and Penicillium polonicum were identified according to growth and morphology. The related strains were found to produce a broad spectrum of fungal metabolites, including roquefortine C, chaetoglobosin A, penitrem A, cyclopeptin, cyclopenin, viridicatin, methylviridicatin, verrucofortine, secalonic acid D, cyclopiazonic acid, fumigaclavine and mycophenolic acid. Chemotaxonomy was performed using high-performance liquid chromatography (HPLC) and mass spectrometry (MS). Dried grape berries were also analyzed allowing to assess the presence of patulin, roquefortine C and penicillic acid; this last one has been identified in dried berries but not in vitro.  相似文献   
134.

Background

Detection of molecular tumor heterogeneity has become of paramount importance with the advent of targeted therapies. Analysis for detection should be comprehensive, timely and based on routinely available tumor samples.

Aim

To evaluate the diagnostic potential of targeted multigene next-generation sequencing (TM-NGS) in characterizing gastrointestinal cancer molecular heterogeneity.

Methods

35 gastrointestinal tract tumors, five of each intestinal type gastric carcinomas, pancreatic ductal adenocarcinomas, pancreatic intraductal papillary mucinous neoplasms, ampulla of Vater carcinomas, hepatocellular carcinomas, cholangiocarcinomas, pancreatic solid pseudopapillary tumors were assessed for mutations in 46 cancer-associated genes, using Ion Torrent semiconductor-based TM-NGS. One ampulla of Vater carcinoma cell line and one hepatic carcinosarcoma served to assess assay sensitivity. TP53, PIK3CA, KRAS, and BRAF mutations were validated by conventional Sanger sequencing.

Results

TM-NGS yielded overlapping results on matched fresh-frozen and formalin-fixed paraffin-embedded (FFPE) tissues, with a mutation detection limit of 1% for fresh-frozen high molecular weight DNA and 2% for FFPE partially degraded DNA. At least one somatic mutation was observed in all tumors tested; multiple alterations were detected in 20/35 (57%) tumors. Seven cancers displayed significant differences in allelic frequencies for distinct mutations, indicating the presence of intratumor molecular heterogeneity; this was confirmed on selected samples by immunohistochemistry of p53 and Smad4, showing concordance with mutational analysis.

Conclusions

TM-NGS is able to detect and quantitate multiple gene alterations from limited amounts of DNA, moving one step closer to a next-generation histopathologic diagnosis that integrates morphologic, immunophenotypic, and multigene mutational analysis on routinely processed tissues, essential for personalized cancer therapy.  相似文献   
135.
Electroless metal deposition is a simple and convenient technique to fabricate metallic films and to provide isotropic metal functionalization of 3D structures with complex geometries. In this work, we describe the synthesis of silver coatings by means of a modified Tollens reaction and their use as optical coating. The chemical composition of the metallization bath is here addressed to optimize the metal coating deposition. The synthesis parameters have been tailored in order to deposit very smooth films which were characterized by scanning electron microscopy, atomic force microscopy, and optical spectroscopy. 2D diffraction gratings and sinusoidal plasmonic gratings were produced with the proposed method. Optical characterization confirmed the plasmonic activities of the resultant structures, proving the efficiency of the described method for optical applications. Thermal annealing was found to improve the surface roughness of the coating and therefore the optical properties of the plasmonic gratings.  相似文献   
136.

Background

Sleep facilitates off-line consolidation of memories, as shown for learning of motor skills in the absence of concomitant distractors. We often perform complex tasks focusing our attention mostly on one single part of them. However, we are equally able to skillfully perform other concurrent tasks. One may even improve performance on disregarded parts of complex tasks, which were learned implicitly. In the present study we investigated the role of sleep in the off-line consolidation of procedural skills when attention is diverted from the procedural task because of interference from a concurrent task.

Methodology/Principal Findings

We used a dual-task paradigm containing (i) procedural serial reaction time task (SRTT), which was labeled as subordinate and unimportant and (ii) declarative word-pair association task (WPAT), performed concomitantly. The WPAT served as a masked distractor to SRTT and was strongly reinforced by the instructions. One experimental and three control groups were tested. The experimental group was re-tested after two nights of sleep (sleep group, SG). The first control group had sleep deprivation on the first post-learning night (nighttime-awake group, NA), the second control group was tested in the morning and then re-tested after 12-hours (daytime-awake group, DA); the third one had the same assignments as DA but with a subsequent, instead of a concomitant, WPAT (daytime-awake-subsequent-WPAT group, DAs). We found SRTT performance gains in SG but not in NA and DA groups. Furthermore, SG reached similar learning gains in SRTT as the DAs group, which gained in SRTT performance because of post-training interference from the declarative task.

Conclusions/Significance

The results demonstrate that sleep allows off-line consolidation, which is resistant to deteriorating effects of a reinforced distractor on the implicit procedural learning and allowing for gains which are consistent with those produced when inhibited declarative memories of SRTT do not compete with procedural ones.  相似文献   
137.
The aim of this work is to quantify the total protein and growth factors content in a tissue-suspension obtained from processed human amniotic membrane (hAM). hAM was collected, frozen, freeze dried, powdered and sterilized by γ-irradiation. At each step of the process, samples were characterized for the total protein amounts by a Bradford protein assay and for the growth factor concentrations by ELISA test of the tissue suspensions. Frozen-hAM samples show higher release of total proteins and specific growth factors in the tissue suspension in comparison with freeze-dried hAM. We observed that even if the protein extraction is hindered once the tissue is dried, the powdering process allows a greater release in the tissue suspension of total proteins and growth factors after tissue re-solubilization in comparison with only the freeze-drying process (+91?±?13% for EGF, +16?±?4% for HGF, +11?±?5% for FGF, +16?±?9% for TGF-β1), and a greater release of EGF (85?±?10%) in comparison with only the freezing process, because proteins become much readily solubilized in the solution. According with these results, we describe a protocol to obtain a new sterile biological product from hAM tissue, with well-known effects of thermal, mechanical and physical processes on the total protein and grow factors contents.  相似文献   
138.
139.
BackgroundWeather conditions can selectively promote the growth of particular fungal species, which cause rotting and spoilage of grape berries before harvest. The presence of pathogenic fungi can lead to the development of opportunist microfungi that can produce mycotoxins and cause grapes and wine contamination.ObjectiveThe variation of climatic conditions allowed to design a pilot study and address relevant questions for risk assessment of climate related mycotoxins production in grapes and in wine.MethodsMicrofungi contaminating berries during the vegetative period of year 2008 and 2009 in vineyards regions of Slovakia at the early veraison and at the ripening in harvest time have been identified.ResultsSpoilage fungi were more abundant in veraison for both years in all the studied geographical regions, with an average temperature of 20 °C, humidity between 60 and 80%, and precipitation in the range 6–5 mm. Much more strains of toxigenic fungi were found during veraison and ripening in the case of a year temperature variation in the range 17–22.5 °C, humidity values ranging from 58 to 80% and precipitations in the range 0.7–8.4 mm.ConclusionsThe results suggest that there is an effect of the climatic conditions on microfungi biodiversity.  相似文献   
140.
Glucose-regulated stress protein gp96 is known to be involved in the host response to pathogens and to cancer. Our study explored the relationships between gp96 and human blood plasmacytoid dendritic cells (pDC) and proved that gp96 directly targets pDC by a receptor-dependent interaction. Competition studies identified CD91 as a gp96 receptor on pDC, and laser confocal imaging indicated that CD91 triggering was followed by gp96 endocytosis and trafficking into early endosomes and later into the endoplasmic reticulum compartment. Using two alternative Abs, we showed that human blood pDC reproducibly expressed CD91, although different levels of expression were detectable among the analyzed donors. Moreover, CpG-matured pDC displayed CD91 receptor up-regulation that correlated with an increased gp96 binding. Functionally, gp96-pDC interaction activated the NF-kappaB pathway, leading to the nuclear translocation of the NF-kappaB complex. gp96-treated pDC maintained an immature phenotype, while they down-modulated the release of IL-8, suggesting an anti-inflammatory role of this pathway, and they strongly up-regulated the cell surface expression of the gp96 receptor CD91. CpG-matured or gp96-treated pDC, expressing high levels of the gp96 receptor CD91, antagonized the gp96-induced activation of monocyte-derived dendritic cells in terms of cell surface phenotype and cytokine production. Altogether, these results suggest that gp96-pDC interaction might represent an active mechanism controlling the strength of the immune response to free, extracellular available gp96; this mechanism could be particularly relevant in wounds and chronic inflammation.  相似文献   
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