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11.
Biliary tract cancers (BTC) represent a heterogeneous and aggressive group of tumors with dismal prognosis. For a long time, BTC has been considered an orphan disease with very limited therapeutic options. In recent years a better understanding of the complex molecular landscape of biology is rapidly changing the therapeutic armamentarium. However, while 40–50% of patients there are molecular drivers susceptible to target therapy, for the remaining population new therapeutic options represent an unsatisfied clinical need. The role of immunotherapy in the continuum of treatment of patients with BTC is still debated. Despite initial signs of antitumor-activity, single-agent immune checkpoint inhibitors (ICIs) demonstrated limited efficacy in an unselected population. Therefore, identifying the best partner to combine ICIs and predictive biomarkers represents a key challenge to optimize the efficacy of immunotherapy. This review provides a critical analysis of completed trials, with an eye on future perspectives and possible biomarkers of response.  相似文献   
12.
Autophagy is a complex process involved in several cell activities, including tissue growth, differentiation, metabolic modulation, and cancer development. In prostate cancer, autophagy has a pivotal role in the regulation of apoptosis and disease progression. Several molecular pathways are involved, including PI3K/AKT/mTOR. However, depending on the cellular context, autophagy may play either a detrimental or a protective role in prostate cancer. For this purpose, current evidence has investigated how autophagy interacts within these complex interactions. In this article, we discuss novel findings about autophagic machinery in order to better understand the therapeutic response and the chemotherapy resistance of prostate cancer. Autophagic-modulation drugs have been employed in clinical trials to regulate autophagy, aiming to improve the response to chemotherapy or to anti-cancer treatments. Furthermore, the genetic signature of autophagy has been found to have a potential means to stratify prostate cancer aggressiveness. Unfortunately, stronger evidence is needed to better understand this field, and the application of these findings in clinical practice still remains poorly feasible.  相似文献   
13.
Common wheat is one of the most important staple food crops worldwide. However, unlike other important staple crops such as maize or soybean, genetically modified (GM) wheat is not yet present in the global food market. Nonetheless, in the recent past, the adventitious presence of GM glyphosate-tolerant volunteers was reported in open wheat fields in the USA. The European Union Reference Laboratory for GM Food and Feed (EURL-GMFF) was therefore called to develop a strategy to detect such unauthorised GM wheat in wheat samples by using both taxon-specific and screening tests. Two candidate common wheat taxon-specific real-time PCR methods were suggested, one targeting ssII-D gene coding for starch synthase and the other targeting waxy-D1 gene, coding for granule-bound starch synthase. In the present study, the two above-mentioned real-time PCR taxon-specific methods were in-house verified and compared, proposing droplet digital PCR (ddPCR) as a new tool for supporting the application of the European Network of GMO Laboratories (ENGL) established method performance criteria. Preliminary performance data of waxy-D1 and ssII-D methods in ddPCR format are shown too to give a contribution to the bridging process from the consolidated to the emerging quantitative PCR methodology.  相似文献   
14.
This study examined the effect of the freeze‐thaw process on the physical properties of films prepared from scleroglucan (Scl) hydrogels, suitable for drug delivery applications. Films made from Scl, using glycerol as plasticizer, were prepared from hydrogels by two procedures: a room temperature drying (RTD) method and a freeze‐thaw cyclic process, before the application of RTD, which results in a reinforced physically cross‐linked network. Films were characterized by studies of water vapor transmission (WVT), swelling, tensile tests, ESEM microscopy, FTIR, and drug release measurements. These determinations showed significant differences between films obtained by both treatments. The films prepared through freeze‐thaw cycles showed an important increase of the tensile strength with respect to those corresponding to films only air dried and a decreasing swelling degree in direct relationship to the number of freeze‐thaw cycles. A model drug, Theophylline, was included in these biocompatible films for in vitro drug release measurements, using a flat Franz cell. The physical differences observed between Scl films prepared with both methods can be explained proposing that the number of crosslinking points by hydrogen bonding increase when increasing the number of freezing and thawing cycles used for film preparation. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
15.
This work is aimed at developing an innovative simulation environment supporting and improving the design of standard joint implants (JPD integrated design environment (JIDE)). The conceptual workflow starts from the design of a new implant, by using conventional CAD programmes and completes with the generation of a report that summarises the goodness for a new implant against a database of human bone anatomies. For each dataset in the database, the JPD application calculates a set of quantitative indicators that will support the designer in the evaluation of its design on a statistical basis. The resulting system is thus directed to prostheses manufacturers and addresses a market segment that appears to have a steady growth in the future.  相似文献   
16.
An electrically switchable graphene terahertz (THz) modulator with a tunable-by-design optical bandwidth is presented and it is exploited to compensate the cavity dispersion of a quantum cascade laser (QCL). Electrostatic gating is achieved by a metal grating used as a gate electrode, with an HfO2/AlOx gate dielectric on top. This is patterned on a polyimide layer, which acts as a quarter wave resonance cavity, coupled with an Au reflector underneath. The authors achieve 90% modulation depth of the intensity, combined with a 20 kHz electrical bandwidth in the 1.9–2.7 THz range. The modulator is then integrated with a multimode THz QCL. By adjusting the modulator operational bandwidth, the authors demonstrate that the graphene modulator can partially compensate the QCL cavity dispersion, resulting in an integrated laser behaving as a stable frequency comb over 35% of the operational range, with 98 equidistant optical modes and a spectral coverage ~1.2 THz. This paves the way for applications in the terahertz, such as tunable transformation-optics devices, active photonic components, adaptive and quantum optics, and metrological tools for spectroscopy at THz frequencies.  相似文献   
17.
18.
Solid dispersions of lonidamine in PEG 4000 and PVP K 29/32 were prepared by the spray-drying method. Then, the binary systems were studied and characterized using differential scanning calorimetry, hot stage microscopy, and x-ray diffractometry. In vitro dissolution studies of the solid dispersed powders were performed to verify if any lonidamine dissolution rate or water solubility improvement occurred. In vivo tests were carried out on the solid dispersions and on the cyclodextrin inclusion complexes to verify if this lonidamine water solubility increase was really able to improve the in vivo drug plasma levels. Drug water solubility was increased by the solid dispersion formation, and the extent of increase depended on the polymer content of the powder. The greater increase of solubility corresponded to the highest content of polymer. Both the solid dispersions and the cyclodextrin complexes were able to improve the in vivo bioavailability of the lonidamine when administered per os. Particularly, the AUC of the drug plasma levels was increased from 1.5 to 1.9-fold depending on the type of carrier.  相似文献   
19.
In this work the fragmental approach was used to prepare several molecularly imprinted ethylene dimethacrylate-co-methacrylic acid polymers with molecular recognition towards the mycotoxin ochratoxin A, with the aim of searching for simpler mimic templates than the well-known N-(4-chloro-1-hydroxy-2-naphthoylamido)-(l)-phenylalanine. The screening for binding of two different kinds of ochratoxin-related molecules was performed by HPLC analysis. Ochratoxin A and the mimic templates were eluted in acetonitrile–acetic acid (0.1% v/v) and the imprinting factor was measured for all the ligands on all the columns packed with the imprinted polymers. The experimental results show that changes to the amino acidic sub-structure or the presence/absence of a chlorine atom in position 4 on the naphthalene ring system does not affect the molecular recognition of ochratoxin A by the resulting imprinted polymer. On the contrary, the presence of the bulky naphthalene ring system in the mimic template seems to be necessary to preserve the molecular recognition of ochratoxin. This binding behavior was found to be compatible with in silico simulations of the complexation between some of the mimic templates and molecules of methacrylic acid. The use of the mimic template N-(1-hydroxy-2-naphthoylamido)-(L)-phenylalanine seems to represent a synthetically simple approach to the preparation of imprinted polymers with molecular recognition properties towards ochratoxin A.  相似文献   
20.
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