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51.
Matrix metalloproteinase‐12 (MMP‐12) can be considered an attractive target to study selective inhibitors useful in the development of new therapies for lung and cardiovascular diseases. In this study, a new series of arylsulfonamide carboxylates, with increased hydrophilicity resulting from conjugation with a β‐N‐acetyl‐d ‐glucosamine moiety, were designed and synthesized as MMP‐12 selective inhibitors. Their inhibitory activity was evaluated on human MMPs by using the fluorimetric assay, and a crystallographic analysis was performed to characterize their binding mode. Among these glycoconjugates, a nanomolar MMP‐12 inhibitor with improved water solubility, compound 3 [(R)‐2‐(N‐(2‐(3‐(2‐acetamido‐2‐deoxy‐β‐d ‐glucopyranosyl)thioureido)ethyl)biphenyl‐4‐ylsulfonamido)‐3‐methylbutanoic acid], was identified.  相似文献   
52.
Congenital diarrheal disorders (CDDs) are a group of inherited enteropathies with a typical onset early in the life. Infants with these disorders have frequently chronic diarrhea of sufficient severity to require parenteral nutrition. For most CDDs the disease-gene is known and molecular analysis may contribute to an unequivocal diagnosis. We review CDDs on the basis of the genetic defect, focusing on the significant contribution of molecular analysis in the complex, multistep diagnostic work-up.  相似文献   
53.
An antimicrobial polyethylene (PE) film was obtained by coating a nisin-based antimicrobial solution. PE sheets were coated on both sides and were used for the packaging of beefsteaks to be stored in air or modified atmosphere packaging (MAP, 60% O(2)-40% CO(2)). Microbial populations, species diversity, headspace volatile organic compounds, colour and sensory properties were monitored after 0, 1, 7 and 12days of storage at 4°C. The viable counts showed that there was an effect of MAP and antimicrobial film on the development of all the spoilage associated microbial populations. Carnobacterium spp., Brochothrix thermosphacta, Pseudomonas fragi and Rhanella aquatilis were found in most of the samples. C. maltaromaticum was identified in MRS bulk cells from samples stored in air as well as MAP. Quantitative data of headspace-SPME-GC/MS analysis showed that during storage the production of volatile organic compounds (VOCs) was affected by the use of the treated film and the MAP storage. Compounds such as phenylethylalcohol, nonanal, decanal and ethylbutanoate were produced only from 7 to 12day of storage and only in the samples stored in air. In agreement with the microbiological and VOCs data, the meat stored in active packaging scored the best rankings in the sensory evaluation. Principal component analysis of microbial, sensory and instrumental data showed that beefsteaks stored with the combination of MAP and active packaging for 12days at 4°C differed from the other samples that were more associated to high microbial loads, VOCs concentration and meat off odour perception. In conclusion, the antimicrobial sheets in combination with MAP storage at 4°C were effective for the storage of beefsteaks by retarding the growth of spoilage bacteria, determining lower concentration of VOCs and keeping acceptable levels of colour and other sensory parameters for more than 10days.  相似文献   
54.
Hypoxia is a key component of the tumor microenvironment (TME) and promotes not only tumor growth and metastasis, but also negatively affects infiltrating immune cells by impairing host immunity. Dendritic cells (DCs) are the most potent antigen-presenting cells and their biology is weakened in the TME in many ways, including the modulation of their viability. RNASET2 belongs to the T2 family of extracellular ribonucleases and, besides its nuclease activity, it exerts many additional functions. Indeed, RNASET2 is involved in several human pathologies, including cancer, and it is functionally relevant in the TME. RNASET2 functions are not restricted to cancer cells and its expression could be relevant also in other cell types which are important players in the TME, including DCs. Therefore, this study aimed to unravel the effect of hypoxia (2% O2) on the expression of RNASET2 in DCs. Here, we showed that hypoxia enhanced the expression and secretion of RNASET2 in human monocyte-derived DCs. This paralleled the HIF-1α accumulation and HIF-dependent and -independent signaling, which are associated with DCs’ survival/autophagy/apoptosis. RNASET2 expression, under hypoxia, was regulated by the PI3K/AKT pathway and was almost completely abolished by TLR4 ligand, LPS. Taken together, these results highlight how hypoxia- dependent and -independent pathways shape RNASET2 expression in DCs, with new perspectives on its implication for TME and, therefore, in anti-tumor immunity.  相似文献   
55.
Microfluidic technique has emerged as a promising tool for the production of stable and monodispersed nanoparticles (NPs). In particular, this work focuses on liposome production by microfluidics and on factors involved in determining liposome characteristics. Traditional fabrication techniques for microfluidic devices suffer from several disadvantages, such as multistep processing and expensive facilities. Three-dimensional printing (3DP) has been revolutionary for microfluidic device production, boasting facile and low-cost fabrication. In this study, microfluidic devices with innovative micromixing patterns were developed using fused deposition modelling (FDM) and liquid crystal display (LCD) printers. To date, this work is the first to study liposome production using LCD-printed microfluidic devices. The current study deals with 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) liposomes with cholesterol (2:1) prepared using commercial and 3D-printed microfluidic devices. We evaluated the effect of microfluidic parameters, chip manufacturing, material, and channel design on liposomal formulation by analysing the size, PDI, and ζ-potential. Curcumin exhibits potent anticancer activity and it has been reported that curcumin-loaded liposomes formulated by microfluidics show enhanced encapsulation efficiency when compared with other reported systems. In this work, curcumal liposomes were produced using the developed microfluidic devices and particle sizing, ζ-potential, encapsulation efficiency, and in vitro release studies were performed at 37 °C.  相似文献   
56.
Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma of childhood. About 25% of RMS expresses fusion oncoproteins such as PAX3/PAX7-FOXO1 (fusion-positive, FP) while fusion-negative (FN)-RMS harbors RAS mutations. Radiotherapy (RT) plays a crucial role in local control but metastatic RMS is often radio-resistant. HDAC inhibitors (HDACi) radio-sensitize different cancer cells types. Thus, we evaluated MS-275 (Entinostat), a Class I and IV HDACi, in combination with RT on RMS cells in vitro and in vivo. MS-275 reversibly hampered cell survival in vitro in FN-RMS RD (RASmut) and irreversibly in FP-RMS RH30 cell lines down-regulating cyclin A, B, and D1, up-regulating p21 and p27 and reducing ERKs activity, and c-Myc expression in RD and PI3K/Akt/mTOR activity and N-Myc expression in RH30 cells. Further, MS-275 and RT combination reduced colony formation ability of RH30 cells. In both cell lines, co-treatment increased DNA damage repair inhibition and reactive oxygen species formation, down-regulated NRF2, SOD, CAT and GPx4 anti-oxidant genes and improved RT ability to induce G2 growth arrest. MS-275 inhibited in vivo growth of RH30 cells and completely prevented the growth of RT-unresponsive RH30 xenografts when combined with radiation. Thus, MS-275 could be considered as a radio-sensitizing agent for the treatment of intrinsically radio-resistant PAX3-FOXO1 RMS.  相似文献   
57.
Helicobacter pylori, a Gram-negative neutrophilic pathogen, is the cause of chronic gastritis, peptic ulcers, and gastric cancer in humans. Current therapeutic regimens suffer from an emerging bacterial resistance rate and poor patience compliance. To improve the discovery of compounds targeting bacterial alternative enzymes or essential pathways such as carbonic anhydrases (CAs), we assessed the anti-H. pylori activity of thymol and carvacrol in terms of CA inhibition, isoform selectivity, growth impairment, biofilm production, and release of associated outer membrane vesicles-eDNA. The microbiological results were correlated by the evaluation in vitro of H. pylori CA inhibition, in silico analysis of the structural requirements to display such isoform selectivity, and the assessment of their limited toxicity against three probiotic species with respect to amoxicillin. Carvacrol and thymol could thus be considered as new lead compounds as alternative H. pylori CA inhibitors or to be used in association with current drugs for the management of H. pylori infection and limiting the spread of antibiotic resistance.  相似文献   
58.
59.
Encapsulation is a promising technology to carry natural active substances, preventing their loss and maintaining their stability until use. Beads of chitosan‐containing propolis have been prepared using a mono‐pore filter device, which permits the encapsulation of natural polyphenols avoiding heat treatments, high shear rates and the use of toxic solvents. Beads proved to be active against Bacillis cereus, Escherichia coli, Listeria innocua, Pseudomonas fluorescens, Yarrovia lipolytica and three moulds strains; the highest effect was found against Staphylococcus aureus (MIC 0.8 mg beads mL?1). Results in liquid cultures of S. aureus evidenced that beads were able to release the flavonoids from propolis: the diffusion of the active compounds is a key factor in the exploitation of the microbial activity. The obtained chitosan–propolis beads represent an example of natural antimicrobial delivery system that could be used to prevent the growth of pathogenic/spoilage bacteria in food applications.  相似文献   
60.
The porosity and pore size distribution of three-dimensional scaffolds have direct implications on their biomedical applications (tissue engineering, drug delivery, and wound dressing). Accordingly, in this paper, a fast, facile, and conservative method relying on low-field nuclear magnetic resonance (LF-NMR) for the evaluation of mean pore size and pore size distribution of polymeric scaffolds is reported. The applicability of the technique is demonstrated on poly-L-lactic acid scaffolds fabricated using the thermal induced phase separation. Results obtained through LF-NMR are successfully compared to scanning electron microscope and X-ray microcomputed tomography micrographs.  相似文献   
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