[Dynamic visual acuity screening test results analysis of 25 patients with peripheral vertigo].

Objective:To observe the results of dynamic visual acuity screening tests in patients with peripheral vertigo and explore its clinical significance. Methods:The number of 48 healthy volunteers were enrolled as control group and 25 peripheral vertigo patients as experimental group. In the experimental group, there are 12 patients with vestibular neuritis, 1 patient with Hunt syndrome, 5 patients with sudden deafness with vertigo and 7 patients with bilateral vestibular dysfunction. Horizontal and vertical dynamic visual acuity screening tests were performed on them. The number of lost rows of horizontal and vertical dynamic visual acuity was compared between the control group and the experimental group to figure out if there is a statistical difference. The number of lost rows of horizontal and vertical dynamic visual acuity was compared within the experimental group to figure out if there is a statistical difference. The two groups of 18 cases of unilateral vestibular function decline and 7 cases of bilateral vestibular function decline in the experimental group were compared with the control group, and figure out if there is a statistical difference. Results:The median number of lost rows of horizontal dynamic visual acuity in 48 healthy volunteers was 1.5 and median number of lost rows of vertical dynamic visual acuity was 1.0 in the control group. The median number of lost rows of horizontal dynamic visual acuity of 26 healthy volunteers was 6 and median number of lost rows of vertical dynamic visual acuity was 5 in the experimental group. Compared to the experimental group, the number of lost rows both have statistical significance in horizontal and vertical dynamic visual acuity（P<0.01）. The comparison of horizontal and vertical lost rows within the test group also have statistical significance（P<0.01）. Twenty five patients with exceptional vestibular disease in the experimental group were divided into unilateral vestibular function reduction group（n=18） and bilateral vestibular function reduction group（n=7）. Compared with the control group, there was significant differences in the number of horizontal and vertical lost rows（P<0.01） within the three groups. After pairwise comparison, the number of lost rows of horizontal and vertical in the control group was significantly lower than that in the unilateral vestibular function reduction group and the bilateral vestibular function reduction group（P<0.01）. There was a highly significant correlation between the number of horizontally lost rows of DVA and the mean vHIT values of bilateral horizontal semicircular canals in 25 patients（P<0.01）; and a highly significant correlation between the number of vertically lost rows of DVA and the mean vHIT values of vertical semicircular canals in 4 groups bilaterally（P<0.01）. Conclusion:The Dynamic Visual Acuity Screening Test is a useful addition to existing tests of peripheral vestibular function, particularly the vHIT test, and provides a rapid assessment of the extent of 2 Hz VOR impairment in patients with reduced vestibular function.

Plastome evolution in the East Asian lobelias (Lobelioideae) using phylogenomic and comparative analyses.

Lobelia species, as rich source of the alkaloid lobeline which has been shown to have important biological activity, have been used in folk medicine throughout East Asia to treat various diseases. However, Lobelia is a complex and varied genus in East Asia and is thus difficult to identify. Genomic resources would aid identification, however the availability of such information is poor, preventing a clear understanding of their evolutionary history from being established. To close this gap in the available genomic data, in this study, 17 plastomes of East Asian lobelias were newly sequenced and assembled. Although the plastomes of Lobelia sect. Hypsela, L. sect. Speirema, and L. sect. Rhynchopetalum shared the gene structure, the inverted repeat (IR)/large single copy (LSC) boundaries, genome size, and the number of repeats were variable, indicating the non-conservative nature of plastome evolution within these sections. However, the genomes of the Lobelia sect. Delostemon and L. sect. Stenotium showed rearrangements, revealing that these two sections might have undergone different evolutionary histories. We assessed nine hotspot genes and 27-51 simple sequence repeat motifs, which will also serve as valuable DNA barcode regions in future population genetics studies and for the delineation of plant species. Our phylogenetic analysis resolved the evolutionary positions of the five sections in agreement with previous evolutionary trees based on morphological features. Although phylogenetic reconstruction of Lobelioideae based on the rpoC2 gene has rarely been performed, our results indicated that it contains a considerable amount of phylogenetic information and offers great promise for further phylogenetic analysis of Lobelioideae. Our site-specific model identified 173 sites under highly positive selections. The branch-site model exhibited 11 positive selection sites involving four genes in the East Asian branches. These four genes may play critical roles in the adaptation of East Asian taxa to diverse environments. Our study is the first to detect plastome organization, phylogenetic utility, and signatures of positive selection in the plastomes of East Asian lobelias, which will help to further advance taxonomic and evolutionary studies and the utilization of medicinal plant resources.

Comparative analysis of plastid genomes within the Campanulaceae and phylogenetic implications.

The conflicts exist between the phylogeny of Campanulaceae based on nuclear ITS sequence and plastid markers, particularly in the subdivision of Cyanantheae (Campanulaceae). Besides, various and complicated plastid genome structures can be found in species of the Campanulaceae. However, limited availability of genomic information largely hinders the studies of molecular evolution and phylogeny of Campanulaceae. We reported the complete plastid genomes of three Cyanantheae species, compared them to eight published Campanulaceae plastomes, and shed light on a deeper understanding of the applicability of plastomes. We found that there were obvious differences among gene order, GC content, gene compositions and IR junctions of LSC/IRa. Almost all protein-coding genes and amino acid sequences showed obvious codon preferences. We identified 14 genes with highly positively selected sites and branch-site model displayed 96 sites under potentially positive selection on the three lineages of phylogenetic tree. Phylogenetic analyses showed that Cyananthus was more closely related to Codonopsis compared with Cyclocodon and also clearly illustrated the relationship among the Cyanantheae species. We also found six coding regions having high nucleotide divergence value. Hotpot regions were considered to be useful molecular markers for resolving phylogenetic relationships and species authentication of Campanulaceae.

The Development and Application of Virtual Reality Animation Simulation Technology: Take Gastroscopy Simulation System as an Example.

Virtual reality (VR) technology has a great potential in the field of medical simulation due to its immersion, interactivity and autonomy. It provides a new direction for integration and application in various disciplines. Combination of VR technology and clinical practice brings great convenience for medical education and experiments. Modern VR simulators can create realistic environments that capture minute anatomical details with high accuracy and solves the problem of difficulty in mass productions with traditional devices. Taking gastroscopy simulation system as an example, this paper discusses the development and application of VR animation technology, together with its excellent performance and current research status in surgery, scientific research, training and education.

The East Asian origin of the giant lobelias.

PREMISE OF THE STUDY: Rapid radiations are difficult to reconstruct when organismal diversification and biogeographic movement outpace the evolution of genes typically used in phylogenetic analyses. The 125 kb of unique sequence from complete plastid genomes (= plastomes) largely solves the molecular sampling problem, and taxon sampling that triangulates the base of each major subclade largely solves the long-branch attraction problem. This combination of molecular and phylogenetic sampling is used to reconstruct the cosmopolitan radiation of lobeliads, with special focus on the origin of the giant lobelias. METHODS: An alignment of 18 previously generated and 61 new plastomes was analyzed to produce the phylogenetic estimate upon which the biogeographic reconstruction was based. KEY RESULTS: Originating in southern Africa, the Lobeliaceae underwent a spectacular cosmopolitan radiation about 20 million years ago. One lineage colonized Madagascar and eastern Asia, which was the source area for the evolution of the giant lobelias. A second lineage colonized the Mediterranean and North America, in quick succession. South America and Australia were also colonized from South Africa, most likely as independent events, but detailed biogeographic reconstruction is limited by inferred extinction events. The south Pacific segregate genera Apetahia and Sclerotheca are inferred to have Hawaiian ancestry. The East African radiation independently reached Ethiopia, West Africa, and Brazil. CONCLUSIONS: With adequate molecular and taxon sampling, many details of rapid radiations can be accurately inferred. However, not all lineages survived, and analyses of extant species cannot recover details that have been lost due to extinction.

Comparative morphology of the leaf epidermis in Lobelia (Lobelioideae) from China.

The leaf epidermal morphology of 38 samples, representing 22 Lobelia species from China, was studied using light microscopy and scanning electron microscopy. The stomata and other epidermal features were largely consistent within species, and therefore represented good characters for taxonomic purposes. Diagnostic characters of the leaf epidermis were used to differentiate species of Lobelia. The species pairs L. clavata and L. pyramidalis, L. alsinoides and L. terminalis, and L. davidii and L. erectiuscula, were differentiated using leaf epidermal characters. Results at the micro-structural level partly supported the current subdivisions of Lobelia. Previous taxonomic revisions of Lobelia in China were evaluated based on species epidermal characteristics. The results supported the recognition of Pratia merged with Lobelia, and of L. chevalieri as a distinct species. Lobelia brevisepala should not be included in L. montana. The status of Lobelia in the evolutionary history of Campanulaceae was assessed. The Lobelia species investigated retained many primitive leaf epidermal features.

Purification antibody by thiophilic magnetic sorbent modified with 2-mercapto-1-methylimidazol.

An efficient strategy based on the thiophilic magnetic beads was developed to isolate immunoglobulin G (IgG) from human plasma with high efficiency. Depending on the improved surface modification, the surface density of thiophilic ligand (2-mercapto-1-methylimidazol) reached 1.67mmolg(-1) resulting in a high adsorption capacity (qmax=20.7mgg(-1)) toward IgG. This purification of IgG could be carried out in some physiological conditions due to the heterocyclic structure of 2-mercapto-1-methylimidazol. It is found that the recognition region between the thiophilic ligand and IgG was mainly focused on the Fab fragments of IgG using the technology of enzyme digestion. Furthermore, the bound antibodies could be easily recovered without loss of their bioactivity at low salt concentration. These magnetic carries brought great potentials in large-scale antibody purification from human plasma attributing to their high specificity and efficiency, stable structure, sensitive magnetic response and excellent reusability.

The maximum number of carbonyl groups around an Ru6C polyhedral cluster: hexanuclear ruthenium carbonyl carbides.

Octahedral, trigonal prismatic, and capped square pyramidal structures have been optimized for the Ru(6)C(CO)(n) clusters (15 ≤ n ≤ 20) using density functional theory. The experimentally known very stable Ru(6)C(CO)(17) is predicted to have an octahedral structure in accord with experiment as well as the Wade-Mingos rules. The stability of Ru(6)C(CO)(17) is indicated by its high carbonyl dissociation energy of ~37 kcal mol(-1) and the high energy of ~33 kcal mol(-1) required for disproportionation into Ru(6)C(CO)(18) + Ru(6)C(CO)(16). Theoretical calculations predict a doubly carbonyl bridged octahedral Ru(6)C(CO)(17) structure to be ~0.7 kcal mol(-1) more stable than the experimentally observed singly bridged structure. A trigonal prismatic Ru(6)C(CO)(19) cluster isoelectronic with the known Co(6)C(CO)(15)(2-) dianion does not appear to be viable as indicated by a low carbonyl dissociation energy of 8.8 kcal mol(-1) and a required energy of only 4.9 kcal mol(-1) for disproportionation into Ru(6)C(CO)(20) + Ru(6)C(CO)(18). The predicted instability of Ru(6)C(CO)(n) (n ≥ 18) derivatives suggests a maximum of 17 external carbonyl groups around a stable polyhedral Ru(6)C structure.

Using thiophilic magnetic beads in purification of antibodies from human serum.

The rapid progress of biotechnology, immunology and molecular biology are requiring antibodies with higher purity and stronger activity. Therefore, the development of efficient technology, which is suitable for large-scale purification of antibodies at low cost, becomes much more urgent. In this study, we presented a novel method to isolate immunoglobulin G from human serum based on the utilization of thiophilic magnetic polymer beads. Micron-sized magnetic beads with paramagnetic properties were synthesized by microsuspension polymerization in the presence of modified magnetite. After the thiophilic ligand of 2-mercaptonicotinic acid was modified on the surface, these magnetic beads exhibited a strong specificity towards immunoglobulin G in a salt-independent manner. Then, antibodies could be directly isolated from human serum in batch-wise mode with the assistance of magnetic decantation. The purity of the isolated antibody exceeded 94%. Because isolation was performed in physiological conditions, bioactivity of the antibody was fully preserved (>99%). Prominent advantages of this method, such as strong specificity, rapid processing, mild conditions, conventional equipment and excellent reusability, make this non-chromatographic technology embody great potentialities to isolate the antibodies on a large scale.

Efficient isolation of immunoglobulin G by paramagnetic polymer beads modified with 2-mercapto-4-mythyl-pyrimidine.

A potential non-chromatographic technique was explored to purify antibody from human serum based on the thiophilic magnetic beads, which were prepared with vinyl acetate and divinylbenzene by microsuspension polymerization. Depending on the effective surface modification of 2-mercapto-4-mythyl-pyrimidine and divinyl-sulfone, the micron-size magnetic beads could selectively capture immunoglobulin G (IgG) from human serum in a non salt-dependent manner. Just because this specific adsorption towards IgG could be carried out in the physiological pH range (5-7) and at low salt concentration (25 mM PBS aqueous solution), the isolated antibody could keep a high purity (92.7%) and strong bioactivity (99%). However, the responding recovery of bound antibodies from magnetic beads was greatly influenced by the types of salt in the eluate. The sodium chloride aqueous solution was much effective to release IgG from these magnetic beads. Because the driving force for this selective recognition was attributed to electron donor-acceptor (EDA) interaction, the effect of temperature on the adsorption was not obvious. Using the successive isolation, the yield of this technology even reached 79.4%. The strong specificity, rapid process, mild conditions and excellent reusability of this technique bring it great potentialities into the antibodies purification on a large scale.