Ultrasound-guided median nerve electrical stimulation to promote upper limb function recovery after stroke

Peripheral electrical nerve stimulation enhances hand function during stroke rehabilitation. Here, we proposed a percutaneous direct median nerve stimulation guided by ultrasound (ultrasound‐guided median nerve electrical stimulation, UG-MNES) and evaluated its feasibility and effectiveness in the treatment of stroke patients with upper limb extremity impairments. Sixty-three stroke patients (2-3 months of onset) were randomly divided into control and UG-MNES groups. Both groups received routine rehabilitation and the UG-MNES group received an additional ultrasound-guided electrical stimulation of the median nerve at 2 Hz, 0.2 ms pulse-width for 20 minutes with gradual intensity enhancement. The Fugl-Meyer Assessment for upper extremity motor function (FMA-UE) was used as the primary outcome. The secondary outcomes were the Functional Test for the Hemiplegic Upper Extremity (FTHUE-HK), Hand Function Rating Scale, Brunnstrom Stages, and Barthel Index scores for motor and daily functions. All the participants completed the trial without any side effects or adverse events during the intervention. After 4 weeks of intervention, the functions of the upper limbs on the hemiplegic side in both groups achieved significant recovery. Compared to the control group, all evaluation indices used in this trial were improved significantly in the UG-MNES group after 2 and 4 weeks of intervention; particularly, the first intervention of UG-MNES immediately improved all the assessment items significantly. In conclusion, the UG-MNES is a safe and feasible treatment for stroke patients with upper limb extremity impairments and could significantly improve the motor function of the affected upper limb, especially in the first intervention. The UG-MNES could be an effective alternative intervention for stroke with upper limb extremity impairments

DNA-Templated Fluorescent Nanoclusters for Metal Ions Detection

DNA-templated fluorescent nanoclusters (NCs) have attracted increasing research interest on account of their prominent features, such as DNA sequence-dependent fluorescence, easy functionalization, wide availability, water solubility, and excellent biocompatibility. Coupling DNA templates with complementary DNA, aptamers, G-quadruplex, and so on has generated a large number of sensors. Additionally, the preparation and applications of DNA-templated fluorescent NCs in these sensing have been widely studied. This review firstly focuses on the properties of DNA-templated fluorescent NCs, and the synthesis of DNA-templated fluorescent NCs with different metals is then discussed. In the third part, we mainly introduce the applications of DNA-templated fluorescent NCs for sensing metal ions. At last, we further discuss the future perspectives of DNA-templated fluorescent NCs in the synthesis and sensing metal ions in the environmental and biological fields

Microsatellite variability reveals high genetic diversity and low genetic differentiation in a critical giant panda population

Understanding present patterns of genetic diversity is critical in order to design effective conservation and management strategies for endangered species. Tangjiahe Nature Reserve (NR) is one of the most important national reserves for giant pandas Ailuropoda melanoleuca in China. Previous studies have shown that giant pandas in Tangjiahe NR may be threatened by population decline and fragmentation. Here we used 10 microsatellite DNA markers to assess the genetic variability in the Tangjiahe population. The results indicate a low level of genetic differentiation between the Hongshihe and Motianling subpopulations in the reserve. Assignment tests using the Bayesian clustering method in STRUCTURE identified one genetic cluster from 42 individuals of the two subpopulations. All individuals from the same subpopulation were assigned to one cluster. This indicates high gene flow between subpopulations. F statistic analyses revealed a low FIS-value of 0.024 in the total population and implies a randomly mating population in Tangjiahe NR. Additionally, our data show a high level of genetic diversity for the Tangjiahe population. Mean allele number (A), Allelic richness (AR) and mean expected heterozygosity (HE) for the Tangjiahe population was 5.9, 5.173 and 0.703, respectively. This wild giant panda population can be restored through concerted effort [Current Zoology 57 (6): 717–724, 2011]

Poly(thymine)-Templated Copper Nanoparticles as a Fluorescent Indicator for Hydrogen Peroxide and Oxidase-Based Biosensing

Biomineralized fluorescent metal nanoparticles have attracted considerable interest in many fields by virtue of their excellent properties in synthesis and application. Poly­(thymine)-templated fluorescent copper nanoparticles (T-CuNPs) as a promising nanomaterial has been exploited by us recently and displays great potential for signal transducing in biochemical analysis. However, the application of T-CuNPs is rare and still at an early stage. Here, a new fluorescent analytical strategy has been developed for H₂O₂ and oxidase-based biosensing by exploiting T-CuNPs as an effective signal indicator. The mechanism is mainly based on the poly­(thymine) length-dependent formation of T-CuNPs and the probe’s oxidative cleavage. In this assay, the probe T40 can effectively template the formation of T-CuNPs by a fast <i>in situ</i> manner in the absence of H₂O₂, with high fluorescent signal, while the probe is cleaved into short-oligonucleotide fragments by hydroxyl radical (·OH) which is formed from the Fenton reaction in the presence of H₂O₂, leading to the decline of fluorescence intensity. By taking advantage of H₂O₂ as a mediator, this strategy is further exploited for oxidase-based biosensing. As the proof-of-concept, glucose in human serum has been chosen as the model system and has been detected, and its practical applicability has been investigated by assay of real clinical blood samples. Results demonstrate that the proposed strategy has not only good detection capability but also eminent detection performance, such as simplicity and low-cost, holding great potential for constructing effective sensors for biochemical and clinical applications

A Reversible Nanolamp for Instantaneous Monitoring of Cyanide Based on an Elsner-Like Reaction

It is well-known that cyanide ion (CN^–) is a hypertoxic anion, which can cause adverse effects in both the environment and living beings; thus, it is highly desirable to develop strategies for detecting CN^–, especially in water and food. However, due to the short half-life of free cyanide, long analysis time and/or interference from other competitive ions are general challenges for accurate monitoring of CN^–. In this work, through the investigation on the sequence-dependent optical interaction of DNA-CuNPs with the fluorophore (e.g., EBMVC-B), we found, for the first time, that DNA-CuNPs were an ideal alternative as fluorescence quencher in constructing a sensor which could be illuminated by CN^– based on an Elsner-like reaction and that the signal switching was dependent on poly­(AT/TA) dsDNA sequence. By virtue of CuNPs’ small size and its high chemical reactivity with cyanide, the lighting of fluorescence was ultrarapid and similar to the hairtrigger “turn-on” of a lamp, which is significant for accurately monitoring a target of short half-life (e.g., cyanide). Attributed to the unique Elsner-like reaction between CN^– and the Cu atoms, high selectivity was achieved for CN^– monitoring by the nanolamp, with practical applications in real water and food samples. In addition, because of the highly efficient <i>in situ</i> formation of DNA-CuNPs and the approximative stoichiometry between CN^– and Cu²⁺ in the fluorescence switching, the nanolamp could be reversibly turned on and off through the alternate regulation of CN^– and Cu²⁺, displaying potential for developing reusable nanosensors and constructing optical molecular logic circuits