Multi-CeIII-Inserted Phospho(III)tungstate Containing Three Building Units with Prominent Peroxidase-Mimicking Activity for Detecting l-Cysteine.

An attractive isonicotinic acid-ornamented octa-CeIII-inserted phospho(III)tungstate [H2N(CH3)2]6Na8[Ce8(H2O)30W8Na2O20(INA)4][HPIIIW4O17]2[HPIIIW9O33]4·30H2O (1-Ce) (HINA = isonicotinic acid) has been isolated through the deliberately designed one-step assembly strategy, in which the HPO32- heteroanion template was introduced into the Ce3+/WO42- system in the presence of HINA. The polyoxoanion of 1-Ce consists of two identical [Ce4(H2O)15W4NaO10(INA)2][HPIIIW4O17][HPIIIW9O33]2}7- subunits linked by Ce-O-W bonds. The polyoxoanion exhibits three kinds of polyoxotungstate building blocks [W4NaO20(INA)2]17-, [HPIIIW4O17]6-, and [HPIIIW9O33]8-, in which [W4NaO20(INA)2]17- and [HPIIIW4O17]6- building units can be considered as seeds driven by the coordination of additional Ce3+ ions to induce aggregation of [HPIIIW9O33]8- fragments. Furthermore, 1-Ce possesses high peroxidase-like activity and can oxidize 3,3',5,5'-tetramethylbenzidine in the presence of H2O2 with a turnover rate of 6.20 × 10-3 s-1. Because l-cysteine (l-Cys) can reduce oxTMB to TMB, the detection of l-Cys was established based on the 1-Ce-based H2O2 colorimetric biosensing platform with the linear range of 5-100 µM and the limit of detection of 4.28 µM. This work not only can expand the scientific research studies on coordination chemistry and materials chemistry of rare-earth-inserted polyoxotungstates but also can provide practical application possibility in clinical diagnosis using liquid biopsy.

Tetrazole-Containing Triphenylamine-Based MOF as a Sensitive Sensor for Food Inspection.

A new metal-organic framework (MOF) with tetrazole-derived triphenylamine (TPA) as the ligand, namely Mn-TPA, has been successfully prepared and thoroughly characterized via thermogravimetric analysis, IR spectroscopy, elemental analysis, UV-vis absorption, fluorescence analysis, bond valence sum calculations, and single-crystal and powder X-ray diffraction analysis. The undulating monolayer of Mn-TPA can hinder the interaction and tight stacking among analytes, which creates a bionic microenvironment for the electrochemical recognition process. Mn-TPA exhibits high specific surface area, stable film-forming capacity, excellent electrochemical activity, and good biocompatibility. Furthermore, the developed Mn-TPA-based immunosensing system exhibits an excellent limit of detection of 0.50 pg·mL-1 toward vomitoxin, which is more outstanding than that of the reported vomitoxin-sensing system. Thus, this work shows the great potential of a well-designed MOF as an easy-to-make and highly sensitive electrochemical platform for biosensing in food safety detection and other fields.

Combined aerobic resistance exercise improves dialysis adequacy and quality of life in patients on maintenance hemodialysis
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OBJECTIVE: This study aims to compare the effect of pure aerobic exercise and combined aerobic resistance exercise on dialysis adequacy and quality of life in patients on maintenance hemodialysis. MATERIALS AND METHODS: A total of 45 patients on maintenance hemodialysis were divided into three groups: pure aerobic exercise group, combined aerobic resistance exercise group, and control group. Patients in the control group were only given the usual treatment, which included dietary guidance, drug therapy, and hemodialysis. The other training groups underwent 12-week exercise intervention therapy on the basis of the usual treatment. Blood samples were collected before and after the hemodialysis, at the beginning and end of the intervention for these three groups. Then, the blood urea nitrogen (BUN) concentration was determined, the urea clearance index (Kt/v) and urea degradation rate (URR) were calculated, the dialysis adequacy was evaluated, and the short form-36 (SF-36) scale was used to evaluate the life quality. RESULTS: Before intervention, there was no significant difference in general health condition (GH), Kt/v, URR, SF-36 total score, and the score of each dimension in the three groups. After the intervention therapy, the Kt/v, URR, GH, vitality (VT), and SF-36 total score markedly improved in the pure aerobic exercise group, while the Kt/v, URR, GH, VT, physical functioning (PF), and SF-36 total score significantly increased in the combined aerobic resistance exercise group. Furthermore, compared with the pure aerobic exercise group, the improvement effect of body function (PF score) was better in the combined aerobic resistance exercise group. CONCLUSION: Both pure aerobic exercise and combined aerobic resistance exercise can significantly improve the dialysis adequacy and quality of life of maintenance hemodialysis patients. Compared with the pure aerobic exercise group, the effect of combined aerobic resistance exercise on PF was better.
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Dual-Functionalized Mixed Keggin- and Lindqvist-Type Cu24-Based POM@MOF for Visible-Light-Driven H2 and O2 Evolution.

The development of logical visible-light-driven heterogeneous photosystems for water splitting is a subject of new research. As the first example of a noble-metal-free photocatalyst for both H2 and O2 production, a high-nuclear {CuI24(µ3-Cl)8(µ4-Cl)6}-based polyoxometalate (POM)@metal-organic framework (MOF) (ZZULI-1) is rationally designed to serve as a robust dual-functionalized photocatalyst. ZZULI-1 exhibits highly efficient photocatalytic H2 evolution (6614 µmol g-1 h-1) and O2 evolution (1032 µmol g-1 calculated for the first 6 min). The {CuI24(µ3-Cl)8(µ4-Cl)6} clusters and mixed POMs not only work as the active units for H2 and O2 production, respectively, but also improve the effective electron transfer between the photosensitizer and ZZULI-1. The highly stable dual-functionalized ZZULI-1 affords new penetrations into the development of cost-effective high-nuclear cluster-based POM@MOFs for efficient solar-to-fuel generation.

Preventative effects of metformin on glucocorticoid-induced osteoporosis in rats.

This study evaluated the preventative effects of metformin (Met) on glucocorticoid (GC)-induced osteoporosis in a rat model, compared with alendronate (Aln). Twenty-eight 3-month-old female Sprague-Dawley rats were randomly assigned into four groups: normal control (Ctr), methylprednisolone (MP, 13 mg/kg/day, sc, 5 days per week), MP plus Aln orally (1 mg/kg/day), and MP plus Met orally (200 mg/kg/day). After 9 weeks, serum bone metabolic biochemistry, bone densitometry and histomorphometry were performed. The GC-induced osteoporosis model was characterized by decreased osteocalcin, increased tartrate-resistant acid phosphatase-5b (TRAP-5b), and decreased bone mineral density (BMD) in the femur and fifth lumbar vertebra (L5). Histomorphometrically, MP significantly decreased trabecular bone volume, decreased bone formation and increased bone resorption in proximal metaphysis, compared with the controls. Aln and Met increased the BMDs of femur (0.305 ± 0.011 vs. 0.280 ± 0.012, P < 0.05; 0.304 ± 0.019 vs. 0.280 ± 0.012, P < 0.05) and L5 (0.399 ± 0.029 vs. 0.358 ± 0.022, P < 0.05; 0.397 ± 0.022 vs. 0.358 ± 0.022, P < 0.05), compared with the model group. Met increased osteocalcin and decreased TRAP-5b, but Aln only decreased TRAP-5b, compared with model group. In histomorphometry of tibial proximal metaphysis, Aln and Met increased trabecular bone volume (39.21 ± 2.46 vs. 30.98 ± 5.83, P < 0.05; 38.97 ± 5.56 vs. 30.98 ± 5.83, P < 0.05), while Met increased the bone formation dynamic parameters and decreased bone resorption dynamic parameters, but Aln just decreased bone resorption dynamic parameters, compared with model group significantly. These findings suggest that metformin prevents GC-induced bone loss by suppressing bone resorption and stimulating bone formation in trabecular bone. The action mode of metformin was different from alendronate, which only suppressed bone resorption.

Semiconductive Copper(I)-Organic Frameworks for Efficient Light-Driven Hydrogen Generation Without Additional Photosensitizers and Cocatalysts.

As the first example of a photocatalytic system for splitting water without additional cocatalysts and photosensitizers, the comparatively cost-effective Cu2 I2 -based MOF, Cu-I-bpy (bpy=4,4'-bipyridine) exhibited highly efficient photocatalytic hydrogen production (7.09 mmol g-1 h-1 ). Density functional theory (DFT) calculations established the electronic structures of Cu-I-bpy with a narrow band gap of 2.05 eV, indicating its semiconductive behavior, which is consistent with the experimental value of 2.00 eV. The proposed mechanism demonstrates that Cu2 I2 clusters of Cu-I-bpy serve as photoelectron generators to accelerate the copper(I) hydride interaction, providing redox reaction sites for hydrogen evolution. The highly stable cocatalyst-free and self-sensitized Cu-I-bpy provides new insights into the future design of cost-effective d10 -based MOFs for highly efficient and long-term solar fuels production.

A photosensitizing decatungstate-based MOF as heterogeneous photocatalyst for the selective C-H alkylation of aliphatic nitriles.

The efficient photosensitizing of decatungstate-based MOF with 1D channels was achieved via in situ synthesis under solvothermal conditions for light driven acceleration of ß- or γ-site C-H alkylation of aliphatic nitriles. The high catalytic efficiency, excellent size selectivity, high stability and good recyclability of the photocatalyst offer an environmentally-friendly route for widening the scope of accessible nitriles in both laboratory and industry.

Organized Aggregation Makes Insoluble Perylene Diimide Efficient for the Reduction of Aryl Halides via Consecutive Visible Light-Induced Electron-Transfer Processes.

The consecutive photo-induced electron-transfer (conPET) process found with perylene diimide (PDI) overcomes the limitation of visible-light photocatalysis and sheds light on effective solar energy conversion. By the incorporation of PDI into a metal-organic polymer Zn-PDI, a heterogeneous approach was achieved to tackle the poor solubility and strong tendency to aggregate of PDIs that restricted the exploitation of this outstanding homogeneous process. The interplay between metal-PDI coordination and π···π stacking of the organized PDI arrays in Zn-PDI facilitates the conPET process for the visible light-driven reduction of aryl halides by stabilizing the radical-anion intermediate and catalyst-substrate interacted moiety. These synergistic effects between the PDI arrays and Zn sites further render Zn-PDI photoactivity for fundamental oxidation of benzyl alcohols and amines. The tunable and modular nature of the two-dimensional metal-organic polymers makes the catalyst-embedding strategy promising for the development of ideal photocatalysts toward the better utilization of solar energy.

Merging of the photocatalysis and copper catalysis in metal-organic frameworks for oxidative C-C bond formation.

The direct formation of new C-C bonds through photocatalytic oxidative coupling from low reactive sp3 C-H bonds using environmentally benign and cheap oxygen as oxidant is an important area in sustainable chemistry. By incorporating the photoredox catalyst [SiW11O39Ru(H2O)]5- into the pores of Cu-based metal-organic frameworks, a new approach for merging Cu-catalysis/Ru-photocatalysis within one single MOF was achieved. The direct CuII-O-W(Ru) bridges made the two metal catalyses being synergetic, enabling the application on the catalysis of the oxidative coupling C-C bond formation from acetophenones and N-phenyl-tetrahydroisoquinoline with excellent conversion and size-selectivity. The method takes advantage of visible light photoredox catalysis to generate iminium ion intermediate from N-phenyl-tetrahydroisoquinoline under mild conditions and the easy combination with Cu-catalyzed activation of nucleophiles. Control catalytic experiments using similar Cu-based sheets but with the photoredox catalytic anions embedded was also investigated for comparison.

Novel polyoxometalate hybrids consisting of copper-lanthanide heterometallic/lanthanide germanotungstate fragments.

Three organic-inorganic hybrid copper-lanthanide heterometallic germanotungstates, {[Cu(en)(2)(H(2)O)] [Cu(3)Eu(en)(3)(OH)(3)(H(2)O)(2)](α-GeW(11)O(39))}(2)·11H(2)O (1), {[Cu(en)(2)(H(2)O)][Cu(3)Tb(en)(3)(OH)(3)(H(2)O)(2)](α-GeW(11)O(39))}(2)·11H(2)O (2) and {[Cu(en)(2)(H(2)O)][Cu(3)Dy(en)(3)(OH)(3)(H(2)O)(2)](α-GeW(11)O(39))}(2)·10H(2)O (3) and three polyoxometalate hybrids built by lanthanide-containing germanotungstates and copper-ethylendiamine complexes, Na(2)H(6)[Cu(en)(2)(H(2)O)](8){Cu(en)(2)[La(α-GeW(11)O(39))(2)](2)}·18H(2)O (4), K(4)H(2)[Cu(en)(2)(H(2)O)(2)](5)[Cu(en)(2)(H(2)O)](2)[Cu(en)(2)](2){Cu(en)(2)[Pr(α-GeW(11)O(39))(2)](2)}·16H(2)O (5) and KNa(2)H(7)[enH(2)](3)[Cu(en)(2)(H(2)O)](2)[Cu(en)(2)](2){Cu(en)(2)[Er(α-GeW(11)O(39))(2)](2)}·15H(2)O (6) (en = ethylenediamine) have been hydrothermally synthesized and structurally characterized by elemental analyses, inductively coupled plasma atomic emission spectrometry (ICP-AES) analyses, IR spectra, powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS) and single-crystal X-ray diffraction. 1-3 are essentially isomorphous and their main skeletons display the interesting dimeric motif {[Cu(3)Ln(en)(3)(OH)(3)(H(2)O)(2)](α-GeW(11)O(39))}(2)(4-), which is constructed from two {Cu(3)LnO(4)} cubane anchored monovacant [α-GeW(11)O(39)](8-) fragments through two W-O-Ln-O-W linkers. The primary backbones of 4-6 exhibit the tetrameric architecture {Cu(en)(2)[Ln(α-GeW(11)O(39))(2)](2)}(24-) built by two 1:2-type [Ln(α-GeW(11)O(39))(2)](13-) moieties and one [Cu(en)(2)](2+) bridge, albeit they are not isostructural. To our knowledge, 1-6 are rare polyoxometalate derivatives consisting of copper-lanthanide heterometallic/lanthanide germanotungstate fragments. 1 exhibits antiferromagnetic coupling interactions within the {Cu(3)EuO(4)} cubane units, while 2 and 3 display dominant ferromagnetic interactions between the Tb(III)/Dy(III) and Cu(II) cations. The room-temperature solid-state photoluminescence properties of 1-3 have been investigated.