[Recent application advances of covalent organic frameworks for solid-phase extraction].

Covalent organic frameworks (COFs) are a type of crystalline porous polymers. It firstly prepared by thermodynamically controlled reversible polymerization to obtain chain units and connecting small organic molecular building units with a certain symmetry. These polymers are widely used in gas adsorption, catalysis, sensing, drug delivery, and many other fields. Solid-phase extraction (SPE) is a fast and simple sample pretreatment technology that can enrich analytes and improve the accuracy and sensitivity of analysis and detection; it is extensively employed in food safety detection, environmental pollutant analysis, and several other fields. How to improve the sensitivity, selectivity, and detection limit of the method during sample pretreatment have become a topic of great interest. COFs have recently been applied to sample pretreatment owing to their low skeleton density, large specific surface area, high porosity, good stability, facile design and modification, simple synthesis, and high selectivity. At present, COFs have also attracted extensive attention as new extraction materials in the field of SPE. These materials have been applied to the extraction and enrichment of diverse types of pollutants in food, environmental, and biological samples, such as heavy metal ions, polycyclic aromatic hydrocarbons, phenol, chlorophenol, chlorobenzene, polybrominated diphenyl ethers, estrogen, drug residues, pesticide residues, etc. COFs can be synthesized from different materials and exert different effects on different extracts. New types of COFs can also be synthesized via modification to achieve better extraction effects. In this work, the main types and synthesis methods of COFs are introduced, and the most important applications of COFs in the fields of food, environment and biology in recent years are highlighted. The development prospects of COFs in the field of SPE are also discussed.

Effects of hyperbaric oxygen therapy on depression and anxiety in the patients with incomplete spinal cord injury (a STROBE-compliant article).

Little research has been done on the effects of hyperbaric oxygen (HBO) on depression and anxiety after spinal cord injury (SCI). The aim of this study was to investigate the effects of HBO on psychological problems and never function, especially on depression and anxiety in the patients with incomplete SCI (ISCI).Sixty patients with ISCI combined with depression and anxiety were randomly divided into HBO group (20 cases), psychotherapy group (20 cases), and conventional rehabilitation control group (20 cases). All patients received routine rehabilitation therapy. However, in HBO group and psychotherapy group, patients also received HBO and psychotherapy, respectively. These therapies lasted for a total of 8 weeks (once a day and 6 days per week). Before and after 8 weeks of treatment, depression and anxiety, nerve function, and activities of daily living were, respectively, evaluated according to Hamilton Depression (HAMD) scale, Hamilton Anxiety (HAMA) scale, American Spinal Injury Association score, and functional independence measure score in all patients.After 8 weeks of treatment, HAMD score was significantly lower in both HBO group and psychotherapy group than in control group (all P < .05), but there was no statistical difference in HAMD score between HBO group and psychotherapy group (P > .05). HAMA score was significantly lower in HBO group than in control group (P < .05), but there was no statistical difference in HAMA score between HBO group and psychotherapy group, and between psychotherapy group and control group (all P > .05). After 8 weeks of treatment, American Spinal Injury Association and functional independence measure scores were significantly higher in HBO group than in both psychological and control groups, and also higher in psychotherapy group than in control group (all P < .05).The effects of HBO on depression and anxiety are similar to that of psychotherapy. HBO can significantly improve nerve function and activities of daily living in the patients with ISCI, which either psychotherapy or routine rehabilitation therapy can not substitute.

Direct visualisation and kinetic analysis of normal and nemaline myopathy actin polymerisation using total internal reflection microscopy.

Actin filaments were formed by elongation of pre-formed nuclei (short crosslinked actin-HMM complexes) that were attached to a microscope cover glass. By using TIRF illumination we could see actin filaments at high contrast despite the presence of 150 nM TRITC-phalloidin in the solution. Actin filaments showed rapid bending and translational movements due to Brownian motion but the presence of the methylcellulose polymer network constrained lateral movement away from the surface. Both the length and the number of filaments increased with time. Some filaments did not change length at all and some filaments joined up end-to-end (annealing). We did not see any decrease in filament length or filament breakage. For quantitative analysis of polymerisation time course we measured the contour length of all the filaments in a frame at a series of time points and also tracked the length of individual filaments over time. Elongation rate was the same measured by both methods (0.23 microm/min at 0.1 microM actin) and was up to 10 times faster than previously published measurements. The annealed filament population reached 30% of the total after 40 min. Polymerisation rate increased linearly with actin concentration. K(on) was 2.07 microm min(-1) microM(-1) (equivalent to 34.5 monomers s(-1) microM(-1)) and critical concentration was less than 20 nM. This technique was used to study polymerisation of a mutant actin (D286G) from a transgenic mouse model. D286G actin elongated at a 40% lower rate than non-transgenic actin.

Genotype-phenotype correlations in ACTA1 mutations that cause congenital myopathies.

Mutations in the skeletal muscle actin gene, ACTA1 are responsible for up to 20% of congenital myopathies with a variety of pathologies that includes nemaline myopathy, intranuclear rod myopathy, actin myopathy and congenital fibre type disproportion. In their review of 2003, Sparrow et al. considered how these actin mutations might affect muscle function at the molecular level and thus cause the disease. Since then several laboratories have taken up the challenge of investigating genotype-phenotype relationships experimentally. The objective of this review is to assess the current state of our understanding of the molecular mechanisms of skeletal myopathies and the prospects for future therapies based on this knowledge. Thirty congenital myopathy-causing ACTA1 mutations have been studied using a range of biochemical and in vitro approaches. They showed diverse molecular defects, and there is no obvious pattern seen in mutations resulting in the same histopathology.

The pathogenesis of ACTA1-related congenital fiber type disproportion.

OBJECTIVE: Mutations in ACTA1 have been associated with a variety of changes in muscle histology that likely result from fundamental differences in the way that ACTA1 mutations disrupt muscle function. Recently, we reported three patients with congenital fiber type disproportion (CFTD) caused by novel heterozygous missense mutations in ACTA1 (D292V, L221P, P332S) with marked type 1 fiber hypotrophy as the only pathological finding on muscle biopsy. We have investigated the basis for the histological differences between these CFTD patients and patients with ACTA1 nemaline myopathy (NM). METHODS AND RESULTS: Mass spectrometry and two-dimensional gel electrophoresis demonstrate that mutant actin accounts for 25 and 50% of alpha-skeletal actin in the skeletal muscle of patients with the P332S and D292V mutations, respectively, consistent with a dominant-negative disease mechanism. In vitro motility studies indicate that abnormal interactions between actin and tropomyosin are the likely principal cause of muscle weakness for D292V, with tropomyosin stabilized in the "switched off" position. Both the D292V and P322S CFTD mutations are associated with normal sarcomeric structure on electron microscopy, which is atypical for severe NM. In contrast, we found no clear difference between ACTA1 mutations associated with NM and CFTD in tendency to polymerize or aggregate in C2C12 expression models. INTERPRETATION: These data suggest that ACTA1 CFTD mutations cause weakness by disrupting sarcomere function rather than structure. We raise the possibility that the presence or absence of structural disorganization when mutant actin incorporates into sarcomeres may be an important determinant of whether the histological patterns of CFTD or NM develop in ACTA1 myopathy.

Fatal hypertrophic cardiomyopathy and nemaline myopathy associated with ACTA1 K336E mutation.

We report on a 2-year-old male child with both nemaline myopathy and hypertrophic cardiomyopathy (HCM). Sequencing of the ACTA1 gene showed a "de novo" missense heterozygous mutation a>g in exon 7 (Lys336Glu). Two-dimensional electrophoresis showed 28% mutant actin present in his muscle biopsy. Actin was isolated from the muscle biopsy and examined by in vitro motility assay. The sliding speed was 13+/-3% less than normal and the affinity of actin for the Z-line protein alpha-actinin was reduced 10 fold. This is the first report on a hypertrophic cardiomyopathy associated with nemaline myopathy and an ACTA1 mutation.