A nonsense mutation in DHTKD1 causes Charcot-Marie-Tooth disease type 2 in a large Chinese pedigree.

Charcot-Marie-Tooth (CMT) disease represents a clinically and genetically heterogeneous group of inherited neuropathies. Here, we report a five-generation family of eight affected individuals with CMT disease type 2, CMT2. Genome-wide linkage analysis showed that the disease phenotype is closely linked to chromosomal region 10p13-14, which spans 5.41 Mb between D10S585 and D10S1477. DNA-sequencing analysis revealed a nonsense mutation, c.1455T>G (p.Tyr485(∗)), in exon 8 of dehydrogenase E1 and transketolase domain-containing 1 (DHTKD1) in all eight affected individuals, but not in other unaffected individuals in this family or in 250 unrelated normal persons. DHTKD1 mRNA expression levels in peripheral blood of affected persons were observed to be half of those in unaffected individuals. In vitro studies have shown that, compared to wild-type mRNA and DHTKD1, mutant mRNA and truncated DHTKD1 are significantly decreased by rapid mRNA decay in transfected cells. Inhibition of nonsense-mediated mRNA decay by UPF1 silencing effectively rescued the decreased levels of mutant mRNA and protein. More importantly, DHTKD1 silencing was found to lead to impaired energy production, evidenced by decreased ATP, total NAD(+) and NADH, and NADH levels. In conclusion, our data demonstrate that the heterozygous nonsense mutation in DHTKD1 is one of CMT2-causative genetic alterations, implicating an important role for DHTKD1 in mitochondrial energy production and neurological development.

Medium entropy FeCoNi nanoalloy supported on reduced graphene oxide for efficient electrochemical detection of roxarsone in food samples.

Herein, a novel FeCoNi(b)-800 ternary metal nanoalloy was uniformly mixed with reduced graphene oxide (RGO) to synthesize the FeCoNi(b)-800@RGO(2:1) composite. The addition of RGO not only stopped the accumulation of FeCoNi(b)-800 alloy, but also heightened the electrocatalytic activity of composite. Particularly, the FeCoNi(b)-800@RGO(2:1) composite displayed the significantly strong electrocatalytic capacity for the reduction of roxarsone (ROX). Furthermore, the FeCoNi(b)-800@RGO(2:1) composite possessed enough porosity and metal catalytic sites, facilitating the transport and electrochemical reduction of the ROX. Thus, the FeCoNi(b)-800@RGO(2:1) composite modified glassy carbon electrode (FeCoNi(b)-800@RGO(2:1)/GCE) showed the superb electrochemical detection effect for ROX with relatively wide working range (0.1-1500 µM) and low detection limit (0.013 µM). Importantly, the FeCoNi(b)-800@RGO(2:1)/GCE sensor could accurately determine the contents of ROX in actual pork, chicken, duck and egg samples, indicating that it had good suitability in food safety monitoring.

Polyrotaxane metal-organic frameworks (PMOFs).

Polyrotaxane metal-organic frameworks (PMOFs), a relatively rare branch of entangled networks, have received significant attention due to their unusual entanglement topologies. The PMOFs we described here are still at an early stage of development. This feature article summarizes the recent developments in structural types of PMOFs from our own group and others. We make some generalizations about the various classes of PMOFs, and develop the definitions and nomenclature of these entanglements, including classification into trivial and nontrivial polyrotaxanes, and limits on what constitutes a (nontrivial) polyrotaxane. Finally, the synthetic strategies toward the design and preparation of new PMOFs are elucidated.

An unprecedented 2D → 3D metal-organic polyrotaxane framework constructed from cadmium and a flexible star-like ligand.

An unprecedented 2D → 3D metal-organic polyrotaxane framework, based on a new star-like tri(4-imidazolylphenyl)amine ligand, has been synthesized and characterized, which represents the first example of 2D → 3D polyrotaxane entangled in a parallel fashion.

Inorganic-organic hybrid materials with different dimensions constructed from copper-fluconazole metal-organic units and Keggin polyanion clusters.

Inorganic-organic hybrid materials based on Keggin polyoxometalate building blocks combined with Cu(II)/Cu(I) and flexible fluconazole ligand [1-(2,4-difluorophenyl)-1,1-bis[(1H-1,2,4-triazol-1-yl)methyl]methanol] (Hfcz) have been obtained by hydrothermal methods, namely, [Cu(II)(2)(Hfcz)(4)(SiW(12)O(40))].3H(2)O (1), [Cu(II)(4)(fcz)(4)(H(2)O)(4)(SiMo(12)O(40))].6H(2)O (2), [Cu(II)(2)(fcz)(2)][Cu(II)(4)(fcz)(4)(SiW(12)O(40))][Cu(II)(2)(fcz)(2)(H(2)O)(2)(SiW(12)O(40))].6H(2)O (3), (Et(3)NH)(2)[Cu(I)(2)(Hfcz)(2)(SiW(12)O(40))].2H(2)O (4), (Et(3)NH)(2)[Cu(I)(2)(Hfcz)(2)(SiW(12)O(40))].H(2)O (5) and [Cu(I)(4)(Hfcz)(4)(SiMo(12)O(40))] (6). Their structures have been determined by single-crystal X-ray diffraction analyses, and the compounds are further characterized by elemental analyses, IR spectra and thermogravimetric (TG) analyses. In 1, Cu(II) cations are bridged by fluconazole ligands to form a 3D lvt coordination polymeric network, which is connected by (SiW(12)O(40))(4-) anions to form a complicated 3D (4,6)-connected framework with the topology of (4(2).6(4))(4(6).6(7).8(2))(2). In 2, two fcz(-) anions chelate two Cu(2+) cations to form a [Cu(fcz)](2)(2+) dimer, which is bridged by (SiW(12)O(40))(4-) polyanions to generate a 2D (4,4) grid. Compound 3 is formed by three types of co-crystallizing subunits including a dimer [Cu(fcz)](2)(2+), a dumbbell molecule [Cu(4)(fcz)(4)(SiW(12)O(40))] and an infinite chain {[Cu(2)(fcz)(2)(H(2)O)(2)(SiW(12)O(40))](2-)}(infinity). In compounds 4 and 5, Hfcz ligands link Cu(+) cations to generate 1D coordination polymeric units, and (SiW(12)O(40))(4-) polyanions connect these metal-organic units to form two types of (6(3)) sheets which are topological isomerism. In compound 6, (SiMo(12)O(40))(4-) polyanions fixed in Cu(I)-Hfcz square rings are further extended into a 2D sheet via linking Cu(I) atoms of different rings. By carefully inspection of the structures of 1-6, it is believed that various transition-metal organic units and Keggin polyanions with different coordination modes are important for the formation of the different structures. In addition, electrochemical behaviors of compounds 1, 2, 5 and 6 have been investigated.

Syntheses and structures of organic-inorganic hybrid compounds based on metal-fluconazole coordination polymers and the beta-Mo8O26 anion.

Five organic-inorganic hybrid compounds, namely, [Co2(fcz)4(H2O)4][beta-Mo8O26].5H2O (1), [Ni2(fcz)4(H2O)4][beta-Mo8O26].5H2O (2), [Zn2(fcz)4(beta-Mo8O26)].4H2O (3), [Cu2(fcz)4(beta-Mo8O26)].4H2O (4), and [Ag4(fcz)4(beta-Mo8O26)] (5), where fcz is fluconazole [2-(2,4-difluorophenyl)-1,3-di(1H-1,2,4-triazol-1-yl)propan-2-ol], were synthesized under hydrothermal conditions, and crystal structures of 1-5 have been determined by X-ray diffraction. In compounds 1 and 2, metal cations are linked by fluconazole ligands to form hinged chain structures and [beta-Mo8O26]4- anions act as counterions. In compound 3, Zn(II) cations are bridged by fluconazole ligands to form 2D (4,4) networks, and each pair of these networks is linked by [beta-Mo8O26]4- anions to form a sandwich double-layer structure. In compound 4, Cu(II) cations are bridged by fluconazole ligands to form 2D (4,4) networks, and these networks are connected by [beta-Mo8O26]4- anions to form a 3D framework. In compound 5, AgI cations and [Ag2]2+ units are bridged by fluconazole ligands to form 2D Ag-fcz layers, and these layers are further connected by [beta-Mo8O26]4- anions to form a complicated 3D structure with the topology of (7(2).8(1))2(7(3).8(3))(7(2).8(11).10(1).12(1))2. Thermogravimetric analyses for these compounds are also discussed in detail. The complexes exhibit antitumor activity in vitro, as shown by MTT experiments.

Syntheses and characterization of six coordination polymers of zinc(II) and cobalt(II) with 1,3,5-benzenetricarboxylate anion and bis(imidazole) ligands.

Six new coordination polymers, namely [Zn1.5(BTC)(L1)(H2O)2].1.5H2O (1), [Zn3(BTC)2(L2)3] (2), [Zn3(BTC)2(L3)1.5(H2O)].H2O (3), [Co6(BTC)4(L1)6(H2O)3].9H2O (4), [Co1.5(BTC)(L2)1.5].0.25H2O (5), and [Co4(BTC)2(L3)2(OH)2(H2O)].4.5H2O (6), where L1 = 1,2-bis(imidazol-1-ylmethyl)benzene, L2 = 1,3-bis(imidazol-1-ylmethyl)benzene, L3 = 1,1'-(1,4-butanediyl)bis(imidazole), and BTC = 1,3,5-benzenetricarboxylate anion, were synthesized under hydrothermal conditions. In 1-6, each of L1-L3 serves as a bidentate bridging ligand. In 1, BTC anions act as tridentate ligands, and compound 1 shows a 2D polymeric structure which consists of 2-fold interpenetrating (6, 3) networks. In compound 2, BTC anions coordinate to zinc cations as tridentate ligands to form a net with (64.82)2(86)(62.8)2 topology. In compound 3, BTC anions act as tetradentate ligands and coordinate to zinc cations to form a net with (4.62.83)2(8.102)(4.6.83.10)2 topology. In compound 5, each BTC anion coordinates to three Co cations, and the framework of 5 can be simplified as (64.82)2(62.82.102)(63)2 topology. For 4 and 6, the 2D cobalt-BTC layers are linked by bis(imidazole) ligands to form 3D frameworks. In 6, the Co centers are connected by micro3-OH and carboxylate O atoms to form two kinds of cobalt-oxygen clusters. Thermogravimetric analyses (TGA) for these compounds are discussed. The luminescent properties for 1-3 and magnetic properties for 4-6 are also discussed in detail.