The combination of an increasing number of new cancer cases and improving survival rates has led to a large and rapidly growing population with unique health-care requirements. Exercise has been proposed as a strategy to help address the issues faced by cancer patients. Supported by a growing body of research, major health organizations commonly identify the importance of incorporating exercise in cancer care and advise patients to be physically active. This systematic review comprehensively summarizes the available epidemiologic and randomized controlled trial evidence investigating the role of exercise in the management of cancer. Literature searches focused on determining the potential impact of exercise on 1) cancer mortality and recurrence and 2) adverse effects of cancer and its treatment. A total of 100 studies were reviewed involving thousands of individual patients whose exercise behavior was assessed following the diagnosis of any type of cancer. Compared with patients who performed no/less exercise, patients who exercised following a diagnosis of cancer were observed to have a lower relative risk of cancer mortality and recurrence and experienced fewer/less severe adverse effects. The findings of this review support the view that exercise is an important adjunct therapy in the management of cancer. Implications on cancer care policy and practice are discussed.

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Alkali phosphates-modified NaY zeolites were developed as catalysts for efficient conversion of lactic acid to acrylic acid. The catalytic performance was optimized in terms of the type and loading of alkali phosphates, reaction temperature, liquid hourly space velocity, and lactic acid concentration. A high acrylic acid yield of 58.4% was achieved at 340 °C over 14 wt % Na2HPO4/NaY. The physicochemical properties of the catalysts were investigated by various techniques including NH3-TPD, pyridine adsorption-FTIR, Raman, and MAS 31P NMR. Introduction of alkali phosphates to NaY zeolite results in a decline of surface acidity. The results of FTIR, Raman, and MAS 31P NMR investigations on the fresh and used catalysts suggest that sodium phosphate is largely transformed to sodium lactate during the reaction. The phosphates and the in situ generated sodium lactate function as highly active species for the target reaction.

We herein report a two-step strategy for oxidative cleavage of lignin C–C bond to aromatic acids and phenols with molecular oxygen as oxidant. In the first step, lignin β-O-4 alcohol was oxidized to β-O-4 ketone over a VOSO4/TEMPO [(2,2,6,6-tetramethylpiperidin-1-yl)­oxyl)] catalyst. In the second step, the C–C bond of β-O-4 linkages was selectively cleaved to acids and phenols by oxidation over a Cu/1,10-phenanthroline catalyst. Computational investigations suggested a copper-oxo-bridged dimer was the catalytically active site for hydrogen-abstraction from Cβ–H bond, which was the rate-determining step for the C–C bond cleavage.

Obtaining high selectivity of aromatic monomers from renewable lignin has been extensively pursued but is still unsuccessful, hampered by the need to efficiently cleave C–O/C–C bonds and inhibit lignin proliferation reactions. Herein, we report a transfer hydrogenolysis protocol using a heterogeneous ZnIn2S4 catalyst driven by visible light. In this process, alcoholic groups (CαH–OH) of lignin act as hydrogen donors. Proliferation of phenolic products to dark substances is suppressed under visible light illumination at low temperature (below 50 °C); formation of a light and transparent reaction solution allows visible light to be absorbed by the catalyst. With this strategy, 71–91% yields of phenols in the conversion of lignin β-O-4 models and a 10% yield of p-hydroxyl acetophenone derivatives from organosolv lignin are achieved. Mechanistic studies reveal that CαH–OH groups of lignin β-O-4 linkage are initially dehydrogenated on ZnIn2S4 to form a “hydrogen pool”, and the adjacent Cβ–O bond is subsequently hydrogenolytically cleaved to two monomers by the “hydrogen pool”. Thus, the dehydrogenation and hydrogenolysis reaction are integrated in one-pot with lignin itself as a hydrogen donor. This study shows a promising way of supplying phenolic compounds by taking advantages of both renewable biomass feedstocks and photoenergy.

The use of deuteration in concert with uniform 15N,13C-labeling has been critical for the chemical shift assignment of several proteins and protein complexes over 30 kDa. Unfortunately, deuteration reduces the number of interproton distance restraints available for structure determination, compromising the precision and accuracy of the NMR-derived structures determined from these samples. We have recently described an isotopic labeling strategy that addresses this problem by generating proteins labeled uniformly with 15N, 13C, and extensively with 2H with high levels of protonation at exchangeable sites and the methyl groups of Val, Leu, and Ile (δ1 only) (Gardner, K. H.; Kay, L. E. J. Am. Chem. Soc. 1997, 119, 7599−7600). This labeling pattern maintains the high efficiency of triple resonance methods while retaining sufficient protons to establish long-range NOEs between secondary structure elements. We demonstrate the utility of samples labeled in this manner by presenting the chemical shift assignments of one of the largest monomeric proteins assigned to date, the 370 residue Escherichia coli maltose binding protein in complex with β-cyclodextrin (42 kDa). The high level of Cα and Cβ deuteration provided by our labeling scheme enabled the collection of triple resonance data with high sensitivity and resolution, allowing assignment of over 95% of the backbone 15N, 13Cα, 1HN, and side chain 13Cβ nuclei. By using a combination of existing experiments and a new pulse scheme described here for correlating methyl chemical shifts with 13Cβ (Val), 13Cγ (Leu), or 13Cγ1 (Ile) carbons, over 98% of methyl 13C and 1H assignments from Val, Leu, and Ile (Cδ1 only) have been obtained. Analysis of the backbone chemical shifts and qualitative HN exchange data have confirmed that the MBP/β-cyclodextrin complex has a secondary structure similar to that previously observed in a 1.8 Å crystal structure.

Recently, it has been reported that addition of a cosolvent significantly influences solubility of cellulose in ionic liquids (ILs), but little is known about the influence mechanism of the cosolvent on the molecular level. In this work, four kinds of typical molecular solvents (dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), CH₃OH, and H₂O) were used to investigate the effect of cosolvents on cellulose dissolution in [C₄mim][CH₃COO] by molecular dynamics simulations and quantum chemistry calculations. It was found that dissolution of cellulose in IL/cosolvent systems is mainly determined by the hydrogen bond interactions between [CH₃COO](-) anions and the hydroxyl protons of cellulose. The effect of cosolvents on the solubility of cellulose is indirectly achieved by influencing such hydrogen bond interactions. The strong preferential solvation of [CH₃COO](-) by the protic solvents (CH₃OH and H₂O) can compete with the cellulose-[CH₃COO](-) interaction in the dissolution process, resulting in decreased cellulose solubility. On the other hand, the aprotic solvents (DMSO and DMF) can partially break down the ionic association of [C₄mim][CH₃COO] by solvation of the cation and anion, but no preferential solvation was observed. The dissociated [CH₃COO](-) would readily interact with cellulose to improve the dissolution of cellulose. Furthermore, the effect of the aprotic solvent-to-IL molar ratio on the dissolution of cellulose in [C₄mim][CH₃COO]/DMSO systems was investigated, and a possible mechanism is proposed. These simulation results provide insight into how a cosolvent affects the dissolution of cellulose in ILs and may motivate further experimental studies in related fields.

Lignin in lignocellulosic biomass is the only renewable source for aromatic compounds, and effective valorization of lignin remains a significant challenge in biomass conversion processes. We have performed density functional theory calculations and experiments to investigate the cleavage mechanism of the C–O ether bond in the lignin model compound 2-phenoxy-1-phenylethanol with a β-O-4 linkage over a Pd(111) catalyst surface model. We propose the favorable reaction pathway to proceed as follows: the dilignol reactant gets dehydrogenated first on the α-carbon and then on the −OH group to generate its corresponding ketone 2-phenoxy-1-phenylethanone; the ketone continues to get dehydrogenated on the β-carbon by first a equilibrated keto–enol tautomerization to its enol form and then −OH dehydrogenation; the C–O ether bond cleavage happens afterward, leading to one-aromatic-ring surface intermediates followed by hydrogenation to yield acetophenone and phenol.