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81.
We report novel molecules incorporating the nontoxic squalene scaffold and different carbonic anhydrase inhibitors (CAIs). Potent inhibitory action, in the low-nanomolar range, was detected against isoforms hCA II for sulfonamide derivatives, which proved to be selective against this isoform over the tumor-associate hCA IX and XII isoforms. On the other hand, coumarin derivatives showed weak potency but high selectivity against the tumor-associated isoform CA IX. These compounds are interesting candidates for preclinical evaluation in glaucoma or various tumors in which the two enzymes are involved. In addition, an in silico study of inhibitor-bound hCA II revealed extensive interactions with the hydrophobic pocket of the active site and provided molecular insights into the binding properties of these new inhibitors.  相似文献   
82.
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   
83.
Drug repurposing strategy, proposing a therapeutic switching of already approved drugs with known medical indications to new therapeutic purposes, has been considered as an efficient approach to unveil novel drug candidates with new pharmacological activities, significantly reducing the cost and shortening the time of de novo drug discovery. Meaningful computational approaches for drug repurposing exploit the principles of the emerging field of Network Medicine, according to which human diseases can be interpreted as local perturbations of the human interactome network, where the molecular determinants of each disease (disease genes) are not randomly scattered, but co-localized in highly interconnected subnetworks (disease modules), whose perturbation is linked to the pathophenotype manifestation. By interpreting drug effects as local perturbations of the interactome, for a drug to be on-target effective against a specific disease or to cause off-target adverse effects, its targets should be in the nearby of disease-associated genes. Here, we used the network-based proximity measure to compute the distance between the drug module and the disease module in the human interactome by exploiting five different metrics (minimum, maximum, mean, median, mode), with the aim to compare different frameworks for highlighting putative repurposable drugs to treat complex human diseases, including malignant breast and prostate neoplasms, schizophrenia, and liver cirrhosis. Whilst the standard metric (that is the minimum) for the network-based proximity remained a valid tool for efficiently screening off-label drugs, we observed that the other implemented metrics specifically predicted further interesting drug candidates worthy of investigation for yielding a potentially significant clinical benefit.  相似文献   
84.
85.
The skin is the largest organ of the human body, serving as an effective mechanical barrier between the internal milieu and the external environment. The skin is widely considered the first-line defence of the body, with an essential function in rejecting pathogens and preventing mechanical, chemical, and physical damages. Keratinocytes are the predominant cells of the outer skin layer, the epidermis, which acts as a mechanical and water-permeability barrier. The epidermis is a permanently renewed tissue where undifferentiated keratinocytes located at the basal layer proliferate and migrate to the overlying layers. During this migration process, keratinocytes undertake a differentiation program known as keratinization process. Dysregulation of this differentiation process can result in a series of skin disorders. In this context, aquaporins (AQPs), a family of membrane channel proteins allowing the movement of water and small neutral solutes, are emerging as important players in skin physiology and skin diseases. Here, we review the role of AQPs in skin keratinization, hydration, keratinocytes proliferation, water retention, barrier repair, wound healing, and immune response activation. We also discuss the dysregulated involvement of AQPs in some common inflammatory dermatological diseases characterised by skin barrier disruption.  相似文献   
86.
Aeromonads in waters and foods can represent a risk to human health. Factors such as sodium chloride concentration and temperature can affect growth and viability of several food and water-borne pathogens. The behaviour of an Aeromonas hydrophila strain in the presence of 1.7%, 3.4% and 6% NaCl concentrations at 24 degrees C and 4 degrees C was studied over a 188 day period. Viability and membrane potential were assessed by flow cytometry; growth was evaluated by plate count technique. Flow cytometry evidenced that A. hydrophila retained viability over the period although varying according to temperature and salt concentrations. Colony Forming Units were generally lower in number than viable cells especially in the presence of 6% NaCl, indicating the occurrence of stressed cells which maintain metabolic activity yet are not able to grow on agar plates. In conclusion, A. hydrophila showed a long-term halotolerance even at elevated (6%) NaCl concentrations and a lesser sensitivity to salt at low temperature; therefore, low temperature and salt, which are two important factors limiting bacterial growth, do not assure safety in the case of high initial contamination. Finally, cytometry appears a valid tool for the rapid detection of the viability of pathogenic bacteria in food and environmental matrices to control and prevent health risks.  相似文献   
87.
Foodborne disease caused by Salmonella represents a worldwide public health problem. In Europe, salmonellosis is still the second most commonly recorded zoonosis. Since the standard culture method for detecting Salmonella (ISO 6579:2002) requires up to 5 days to produce results, the need to develop rapid methods represents an important issue for the authorities and the producers. The aim of the present study was the in-house validation, according to ISO 16140, of an open-formula diagnostic real-time PCR for the detection of Salmonella in all the different meat categories reported in the EU Regulations relative to microbiological criteria for food safety. The assay employed specific primers and a probe target within the ttrRSBCA locus, which allows the tetrathionate respiration in Salmonella. Selectivity, relative accuracy, relative sensitivity and relative specificity were established by testing 110 bacterial strains and 175 various edible meat samples. Results showed 100 % selectivity, 100 % relative accuracy, 100 % relative sensitivity and 100 % relative specificity of the real-time PCR when compared to the standard culture method used as reference. In addition, in order to minimize the effect of the competitive micro-flora naturally present on meat samples, a highly nutritious and selective commercial medium (ONE Broth Salmonella, Oxoid) was evaluated in comparison with the classical non-selective pre-enrichment broth (buffered peptone water). Results demonstrated that the ONE Broth Salmonella medium increases the growth of Salmonella in the presence of competitive micro-flora.  相似文献   
88.
89.
High levels of soy flour added to wheat bread produce negative effects on gluten network formation, dough properties, and on bread final quality. The objective of this study was to assess the influence of three enzymes, transglutaminase (TG), glucose oxidase (GOX), and endoxylanase (XYL), on dough properties and final quality of high-protein breads. The addition of TG and GOX increased the mixing stability and maximum resistance of dough, decreased its extensibility, and produced stronger and more consistent dough samples. XYL incorporation produced opposite results. XYL addition and the lowest GOX dose increased bread volume significantly and decreased initial crumb firmness, while high doses of TG (0.3%) produced detrimental effects on bread volume and crumb firmness. In conclusion, XYL and GOX 0.001% addition improved the final quality of soy-fortified breads, but XYL was the best additive to improve dough properties, bread volume, and quality.  相似文献   
90.
In this study the satiating capacity of three beverages containing 3 g barley β-glucan, or 2.5 g dietary fibre (DF) from fruit, or without DF (control) was evaluated. Fourteen healthy volunteers were randomized to have isocaloric breakfasts including one of the beverages in different occasions. Appetite ratings over 3 h post-breakfast and energy intakes at ad libitum lunch, blood glucose, insulin, ghrelin, PYY, GLP-1, GIP, and PP concentrations, and 24 h food intake, were assessed. The bevaerages containing DF increased fullness and satiety over 3 h post-breakfast, but only the β-glucan-enriched vs. the control significantly reduced energy intakes by 18% at lunch and 40% over the rest of the day. Blood ghrelin and PP responses were differently modulated by beverages. The fruit-based and the β-glucan-enriched beverage suppressed by 8.9% and 8.1% ghrelin response over the 3 h and the first hour post-breakfast, respectively, while only the latter increased PP response by 34.6%, compared to the control. A sucrose-sweetened beverage providing 3 g barley β-glucans can control food intake by modulating PP response and it can even reduce 24 h energy intake. Ghrelin suppression by fruit dietary fibre and mixed sugars was not sufficient to significantly reduce food intake compared to the control.  相似文献   
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