A novel concept for the synthesis of halogenated, conjugated dienes is disclosed: the CpTiCl2‐catalyzed coupling of keto‐alkynes, in the presence of Me3SiBr/Et3N⋅HBr. This reaction provided five‐, ...six‐, and seven‐membered carbocycles, nitrogenated heterocycles, as well as six‐membered oxygenated heterocycles leading to a brominated conjugate diene. These products showed high reactivity in the Diels–Alder, Suzuki, and Sonogashira reactions, giving complex chemical structures in only three steps from the corresponding acyclic keto‐alkyne. Hopefully, this strategy will pave the way towards the synthesis of bioactive natural products and new materials.
Synthesis of bicyclic product III, from acyclic keto‐alkyne I, catalyzed by CpTiIIICl2, followed by a Diels–Alder cycloaddition provided III in an acceptable overall yield. Ten CpTiIIICl2‐catalyzed cyclizations and seven Diels–Alder reactions are reported. Moreover, seven and five examples of the Suzuki and Sonogashira cross‐couplings with halogenated dienes obtained from the above cyclizations are also described.
The robust Zn4O(3,5-dimethyl-4-carboxypyrazolato)3 (Zn4O(dmcapz)3) 3D metal-organic framework (MOF) is studied as a suitable platform for the controlled release of bioactive molecules. With this aim, ...a simple ball milling technique is used to efficiently encapsulate the model drugs 5-fluorouracil, caffeine, para-aminobenzoic acid, and benzocaine. Both computational and experimental studies confirm the suitability of Zn4O(dmcapz)3 to incorporate high loadings of the studied bioactive molecules. The results show that the physicochemical properties of bioactive molecule effects on the loading efficiency on the MOF structure. The controlled release of the bioactive molecules from drug@Zn4O(dmcapz)3 is studied under simulated cutaneous conditions to prove its suitability as topical drug delivery systems. In this regard, 5-fluorouracil@Zn4O(dmcapz)3 system is incorporated in the preoxidized cellulosic fabric to demonstrate their possible application for antibacterial treatment and skin cancer therapy. The results show that the 5-fluorouracil@Zn4O(dmcapz)3 loaded cellulosic fabrics exhibit potentially significant anticancer and antibacterial activities.
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•A mechanochemical technique efficiently encapsulates the model bioactive molecule.•Different uptake behavior highlights the importance of drug-framework interaction.•Controlling drug delivery is affected by the physicochemical properties of cargoes.•Cellulose substrate is preoxidized to attain the carboxyl functional group.•5-fluorouracil@MOF applied on cellulose for skin cancer and antibacterial treatment.
Oysters and blue mussels are important hydrobiological resources for aquaculture. In Chile, they are farming on the Chiloé island, where around 18% of the world’s mussels are produced, however, their ...nutritional dynamics are largely unknown. For this reason, the objective of this study was to determine the proximal biochemical composition and the fatty acid profile in the Chilean oyster (
Ostrea chilensis
), the Pacific oyster (C
rassostrea gigas
) and the Chilean mussel (
Mytilus chilensis
), to perform an intra and interspecific comparison. Shellfish sampled in winter were characterized by a high protein content, followed by medium values for lipid content and a low carbohydrate content compared to similar species in Europe. Also, oysters and mussels were found to be rich in omega-3 long chain polyunsaturated fatty acid (n-3 LC-PUFA), so they can be considered excellent functional food option for a healthy human diet. Their high contribution of n-3 LC-PUFA ranged between 5.2–12.9 μg FA mg
-1
dry weight with high n-3/n-6 ratios, which depends on both the species and the on-growing location. Both taxa can be considered a plausible option to promote a healthy diet of marine origin in future generations. Also, these results could benefit the projection and development of aquaculture of these mollusks.
The adsorptive properties of the isoreticular series Ni8(OH)4(H2O)2(BDP_X)6 (H2BDP_X = 1,4‐bis(pyrazol‐4‐yl)benzene‐4‐X with X = H (1), OH (2), NH2 (3)) can be enhanced by postsynthetic treatment ...with an excess of KOH in ethanol. In the case of X = H, NH2, this treatment leads to partial removal of the organic linkers, deprotonation of coordinated water molecules and introduction of extraframework cations, giving rise to materials of KNi8(OH)5(EtO)‐(H2O)2(BDP_X)5.5 (1@KOH, 3@KOH) formulation, in which the original framework topology is maintained. By contrast, the same treatment with KOH in the Ni8(OH)4(H2O)2(BDP_OH)6 (2) system, enclosing the more acidic phenol residues, leads to a new material containing a larger fraction of missing linker defects and extra‐framework cations as well as phenolate residues, giving rise to the material K3Ni8(OH)3(EtO)(H2O)6(BDP_O)5 (2@KOH), which also conserves the original face cubic centered (fcu) topology. It is noteworthy that the introduction of missing linker defects leads to a higher accessible pore volume with a concomitant increased adsorption capacity. Moreover, the creation of coordinatively unsaturated metal centers, charge gradients, and phenolate nucleophilic sites in 2@KOH gives rise to a boosting of CO2 capture features with increased adsorption heat and adsorption capacity, as proven by the measurement of pulse gas chromatography and breakthrough curve measurements of simulated flue gas.
A boosting of CO2 capture properties in a series of functional MOF materials can be achieved by post‐synthetic treatment with KOH ethanolic solutions, leading to linker removal and the concomitant creation of highly active surface sites for the adsorption of acidic gases.
To evaluate the accuracy of shear-wave elastography (SWE) for staging liver fibrosis in patients with diffuse liver disease (including patients with hepatitis C virus HCV) and to determine the ...relative accuracy of SWE measurements obtained from different hepatic acquisition sites for staging liver fibrosis.
The institutional review board approved this single-institution prospective study, which was performed between January 2010 and March 2013 in 136 consecutive patients who underwent SWE before their scheduled liver biopsy (age range, 18-76 years; mean age, 49 years; 70 men, 66 women). Informed consent was obtained from all patients. SWE measurements were obtained at four sites in the liver. Biopsy specimens were reviewed in a blinded manner by a pathologist using METAVIR criteria. SWE measurements and biopsy results were compared by using the Spearman correlation and receiver operating characteristic (ROC) curve analysis.
SWE values obtained at the upper right lobe showed the highest correlation with estimation of fibrosis (r = 0.41, P < .001). Inflammation and steatosis did not show any correlation with SWE values except for values from the left lobe, which showed correlation with steatosis (r = 0.24, P = .004). The area under the ROC curve (AUC) in the differentiation of stage F2 fibrosis or greater, stage F3 fibrosis or greater, and stage F4 fibrosis was 0.77 (95% confidence interval CI: 0.68, 0.86), 0.82 (95% CI: 0.75, 0.91), and 0.82 (95% CI: 0.70, 0.95), respectively, for all subjects who underwent liver biopsy. The corresponding AUCs for the subset of patients with HCV were 0.80 (95% CI: 0.67, 0.92), 0.82 (95% CI: 0.70, 0.95), and 0.89 (95% CI: 0.73, 1.00). The adjusted AUCs for differentiating stage F2 or greater fibrosis in patients with chronic liver disease and those with HCV were 0.84 and 0.87, respectively.
SWE estimates of liver stiffness obtained from the right upper lobe showed the best correlation with liver fibrosis severity and can potentially be used as a noninvasive test to differentiate intermediate degrees of liver fibrosis in patients with liver disease.
In this paper, we propose a procedure to build bivariate box plots (BBP). We first obtain the theoretical BBP for a random vector (
,
). They are based on the univariate box plot of
and the ...conditional quantile curves of
. They can be computed from the copula of (
,
) and the marginal distributions. The main advantage of these BBP is that the coverage probabilities of the regions are distribution-free. So they can be selected by the users with the desired probabilities and they can be used to perform fit tests. Three reasonable options are proposed. They are illustrated with two examples from a normal model and an exponential model with a Clayton copula. Moreover, several methods to estimate the theoretical BBP are discussed. The main ones are based on linear and non-linear quantile regression. The others are based on empirical estimators and parametric and non-parametric (kernel) copula estimations. All of them can be used to get empirical BBP. Some extensions for the multivariate case are proposed as well.
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