Characterization of abnormal epithelium after laser-assisted subepithelial keratectomy using in vivo confocal microscopy

This study compared the abnormal corneal epithelium after laser-assisted subepithelial keratectomy (LASEK) with dystrophic cornea using in vivo using confocal microscopy (IVCM) and examined the effects of the abnormal epithelium on postoperative recovery of uncorrected distance visual acuity (UDVA) and sub-basal nerve plexus regeneration. The UDVA and wound healing were examined in 50 eyes of 25 patients undergoing LASEK at 1 week, 1 month, and 1 year postoperatively, including the visual acuity, slit lamp microscopy, and IVCM. After 1 week, the corneal epithelium was healed in all patients, but abnormal epithelial cells were detected in 33/50 patients using IVCM. Abnormal cells were limited to the surgical margin, and highly reflective granules were observed underneath. At 1 month and 1 year postoperatively, the abnormal epithelium was unchanged in size. At 1 year postoperatively, there were clear differences between the sub-basal nerve plexus in the normal and abnormal epithelium. At 1 month postoperatively, the UDVA was >1.0 in 88% of patients, which increased to 94% at 1 year, and there was no clear difference in the UDVA between abnormal (N = 33) and normal (N = 17) epithelium. After LASEK, abnormal epithelial cells may arise at the margin of the epithelial flap and persist 1 year postoperatively accompanied by poor regeneration of the sub-basal nerve plexus. However, this does not affect the UDVA postoperatively. The abnormal epithelium may be caused by residual necrotic basal cell debris on the epithelial basement membrane and abnormal neurotrophic metabolism between the corneal epithelium and nerve plexus.

Immune influence of pregnancy on human H7N9 infection: a case report

INTRODUCTION

H7N9 infection has raised serious concerns worldwide. Pregnant women were considered to be at a high risk of influenza infection. Normal pregnancy was dependent on T helper (Th) 2 deviation. However, whether pregnancy influences the immune status of influenza H7N9 patients has not been reported.

CASE REPORT

Here, we reported a case of pregnant woman in the first trimester with H7N9 infection compared with the two non-pregnant female H7N9 patients for clinical features and relevant immunological changes. We found that there were no differences in plasma levels of Th1 and Th2 cytokines between the pregnant and non-pregnant patients, and there was no Th2 deviation in the acute phase. However, the Th2 deviation was recurrent along with the clearance of infection in the H7N9 pregnant patient.

CONCLUSION

These cases highlighted that the pregnant patient infected with H7N9 could induce an effective Th1 immune response equal to that of non-pregnant patients with H7N9 virus infection, although the pregnancy itself could lead to a Th2 deviation. These data suggested that pregnant patients could acquire a similar antiviral response for H7N9 infection versus non-pregnant patients.

SRNAome parsing yields insights into tomato fruit ripening control

Small RNAs have emerged as critical regulators in the expression and function of eukaryotic genomes at the post-transcriptional level. To elucidate the functions of microRNA (miRNAs) and endogenous small-interfering RNAs (siRNAs) in tomato fruit ripening process, the deep sequencing and bioinformatics methods were combined to parse the small RNAs landscape in three fruit-ripening stages (mature green, breaker and red-ripe) on a whole genome. Two species-specific miRNAs and two members of TAS3 family were identified, 590 putative phased small RNAs and 125 cis-natural antisense (nat-siRNAs) were also found in our results which enriched the tomato small RNAs repository and all of them showed differential expression patterns during fruit ripening. A large amount of the targets of the small RNAs were predicted to be involved in fruit ripening and ethylene pathway. Furthermore, the promoters of the conserved and novel miRNAs were found to contain the conserved motifs of TATA-box and CT microsatellites which were also found in Arabidopsis and rice, and several species-specific motifs were found in parallel.

Deciphering ascorbic acid regulatory pathways in ripening tomato fruit using a weighted gene correlation network analysis approach

Genotype is generally determined by the co-expression of diverse genes and multiple regulatory pathways in plants. Gene co-expression analysis combining with physiological trait data provides very important information about the gene function and regulatory mechanism. L-Ascorbic acid (AsA), which is an essential nutrient component for human health and plant metabolism, plays key roles in diverse biological processes such as cell cycle, cell expansion, stress resistance, hormone synthesis, and signaling. Here, we applied a weighted gene correlation network analysis approach based on gene expression values and AsA content data in ripening tomato (Solanum lycopersicum L.) fruit with different AsA content levels, which leads to identification of AsA relevant modules and vital genes in AsA regulatory pathways. Twenty-four modules were compartmentalized according to gene expression profiling. Among these modules, one negatively related module containing genes involved in redox processes and one positively related module enriched with genes involved in AsA biosynthetic and recycling pathways were further analyzed. The present work herein indicates that redox pathways as well as hormone-signal pathways are closely correlated with AsA accumulation in ripening tomato fruit, and allowed us to prioritize candidate genes for follow-up studies to dissect this interplay at the biochemical and molecular level.

Bis-enoxacin inhibits bone resorption and orthodontic tooth movement

Enoxacin inhibits binding between the B-subunit of vacuolar H(+)-ATPase (V-ATPase) and microfilaments, and also between osteoclast formation and bone resorption in vitro. We hypothesized that a bisphosphonate derivative of enoxacin, bis-enoxacin (BE), which was previously studied as a bone-directed antibiotic, might have similar activities. BE shared a number of characteristics with enoxacin: It blocked binding between the recombinant B-subunit and microfilaments and inhibited osteoclastogenesis in cell culture with IC50s of about 10 µM in each case. BE did not alter the relative expression levels of various osteoclast-specific proteins. Even though tartrate-resistant acid phosphatase 5b was expressed, proteolytic activation of the latent pro-enzyme was inhibited. However, unlike enoxacin, BE stimulated caspase-3 activity. BE bound to bone slices and inhibited bone resorption by osteoclasts on BE-coated bone slices in cell culture. BE reduced the amount of orthodontic tooth movement achieved in rats after 28 days. Analysis of these data suggests that BE is a novel anti-resorptive molecule that is active both in vitro and in vivo and may have clinical uses.

ABBREVIATIONS

BE, bis-enoxacin; V-ATPase, vacuolar H(+)-ATPase; TRAP, tartrate-resistant acid phosphatase; αMEM D10, minimal essential media, alpha modification with 10% fetal bovine serum; SDS-PAGE, sodium dodecyl sulfate-polyacrylamide gel electrophoresis; RANKL, receptor activator of nuclear factor kappa B-ligand; NFATc1, nuclear factor of activated T-cells; ADAM, a disintegrin and metalloprotease domain; OTM, orthodontic tooth movement.

[Changes in the number and distribution of myoepithelial cells during atrophy of rat parotid gland]

OBJECTIVE

To investigate the changes in the number and distribution of myoepithelial cells during atrophy of the rat parotid gland.

METHODS

Atrophy of the right parotid was induced by ligating the right stensen duct of rats, histological changes of parotid glands were examined by hematoxylin-eosin (HE) staining during each step of glandular atrophy at the time of 0 (control), 1, 3, 5, 7, 14, 21, 30, 60, 100, and 150 days after ligation. Immunohistochemical labelling was performed to study the changes in number and distribution of myoepithelial cells during atrophy of the rat parotid gland.

RESULTS

Histological analysis showed disappearance of the acini at 5 d and gradual decrease and fibrosis of the glandular lobules accompanied by the occurrence of duct-like structures. Quantitative analysis of myoepithelial cells showed significant increase in number up to day 5 after ligation, then followed by gradual increases at a low level, at last it was followed by a rapid decrease after the total number reached the peak in 100 days. In addition, the acini and intercalated ducts were covered by myoepithelial cells ranged from the shape of spindle to stellate during the early phase of atrophy, while spindle-shaped myoepithelial cells were located at the periphery of duct-like structures in the later phase of atrophy.

CONCLUSION

Myoepithelial cells proliferated rapidly up to day 5 after ligation, then followed by gradual increase at a low level, at last it was followed by a rapid decrease after the total number reached the peak in 100 days.

Virus-induced gene silencing in eggplant (Solanum melongena)

Eggplant (Solanum melongena) is an economically important vegetable requiring investigation into its various genomic functions. The current limitation in the investigation of genomic function in eggplant is the lack of effective tools available for conducting functional assays. Virus-induced gene silencing (VIGS) has played a critical role in the functional genetic analyses. In this paper, TRV-mediated VIGS was successfully elicited in eggplant. We first cloned the CDS sequence of PDS (PHYTOENE DESATURASE) in eggplant and then silenced the PDS gene. Photo-bleaching was shown on the newly-developed leaves four weeks after agroinoculation, indicating that VIGS can be used to silence genes in eggplant. To further illustrate the reliability of VIGS in eggplant, we selected Chl H, Su and CLA1 as reporters to elicit VIGS using the high-pressure spray method. Suppression of Chl H and Su led to yellow leaves, while the depletion of CLA1 resulted in albino. In conclusion, four genes, PDS, Chl H, Su (Sulfur), CLA1, were down-regulated significantly by VIGS, indicating that the VIGS system can be successfully applied in eggplant and is a reliable tool for the study of gene function.

Comparison of adsorption of mercaptopropyltrimethoxysilane on amphiphilic TiO2 and hydroxylated SiO2

Alkylsilane 3-mercaptopropyltrimethoxysilane (3MPT) monolayers with a functional end group -SH were used to immobilize Ag colloidal nanoparticles on photoinduced amphiphilic TiO(2) and hydroxylated SiO(2) surfaces. The differences in the adsorption of 3MPT and the immobilization of Ag colloids on both surfaces were studied. Under identical experimental conditions, 3MPT islands were formed on UV-exposed TiO(2) surfaces compared to continuous and flat monolayers formed on SiO(2). The significant structural differences found for monolayers of 3MPT on TiO(2) could be explained in terms of the different densities of hydroxyl groups and the microstructure of hydrophilic domains induced by UV irradiation. The surface properties were characterized using contact angle measurements and XPS. XPS showed an increase in the hydroxyl group's density and a decrease in the number of adsorbed hydrocarbon films on the TiO(2) surface as a function of the UV irradiation time. The density of the adsorbed 3MPT on TiO(2) surfaces as a function of the UV irradiation time was quantitatively related to the cosine of the water contact angles. Such a 3MPT distribution influenced the subsequent adsorption of Ag colloids and resulted in more isolated nanoparticles on the modified TiO(2) with a narrower size distribution.

A micro creeping robot for colonoscopy based on the earthworm

Minimally Invasive Surgery (MIS) has become one of the most important research areas in the field of medical engineering. Robotic colonoscopy is a typical medical procedure that complies with the requirements of MIS. In this paper, a new novel miniature robot for intestinal inspection based on the earthworm is described; its diameter and length are 7.5 mm and 120 mm respectively. The micro robot is driven by a DC motor which has good performance and sufficient power. In this paper the structure and locomotion mechanism of this robot are introduced; the mechanical model is built; and simulation is carried out. The control system and software design are also discussed in detail. Some actuating characteristic experiments have been performed, where the micro robot creeps in declining rubber tubes. The experimental results are in accord with simulation results, and show that this kind of robot can move reliably in horizontal and certain declining tubes. This research has laid a foundation for the application of the miniature robot endoscope.

Collapse and stability of single- and multi-wall carbon nanotubes

The collapse and stability of carbon nanotubes (CNTs) have important implications for their synthesis and applications. While nanotube collapse has been observed experimentally, the conditions for the collapse, especially its dependence on tube structures, are not clear. We have studied the energetics of the collapse of single- and multi-wall CNTs via atomistic simulations. The collapse is governed by the number of walls and the radius of the inner-most wall. The collapsed structure is energetically favored about a certain diameter, which is 4.12, 4.96 and 5.76 nm for single-, double- and triple-wall CNTs, respectively. The CNT chirality also has a strong influence on the collapsed structure, leading to flat, warped and twisted CNTs, depending on the chiral angle.

Evaluation of an independent prestin mouse model derived from the 129S1 strain

Studies using the prestin knockout mouse indicate that removal of the outer hair cell (OHC) motor protein is associated with loss of sensitivity, frequency selectivity and somatic electromotility. Here we provide data obtained from another prestin mouse model that was produced commercially. In vivo electrical recordings from the round window indicate that the phenotype is similar to that of the original knockout generated by the Zuo group at St. Jude Children's Research Hospital. Hence, compound action potential (CAP) thresholds are shifted in a frequency-dependent manner and CAP tuning curves at 12 kHz are flat for masker frequencies between 3 and 18 kHz. Although CAP input-output functions at 6 kHz show a shift in sensitivity at low levels, responses approach wild-type magnitudes at high levels where the cochlear amplifier has less influence. In order to confirm that the loss of sensitivity and frequency selectivity is due to loss of prestin, we performed immunohistochemistry using a prestin antibody. Cochlear segments from homozygous mutant mice showed no fluorescence, while wild-type mice displayed a fluorescent signal targeted to the OHC's lateral membrane. Absence of prestin protein was confirmed using LDS-PAGE/Western blot analysis. These results indicate that the loss of function phenotype is associated with loss of prestin protein. Lack of prestin protein also results in a shortening of OHC length to approximately 60% of wild-type, similar to that reported previously by Liberman's group. The linkage shown between the loss of prestin protein and abnormal cochlear function validates the original knockout and attests to the importance of OHC motor function in the auditory periphery.

Nuclear factor kappaB p65 phosphorylation in orthodontic tooth movement

Osteoclasts play a vital role in orthodontic tooth movement. Transactivation of nuclear factor kappaB (NFkappaB) by phosphorylation of the p65 component of NFkappaB at amino acid 536 (p65*(536)) plays a role in osteoclast differentiation stimulated by receptor activator of nuclear factor kappaB-ligand (RANK-L). We hypothesized that this transactivation pathway might be involved in the responses of alveolar bone cells during orthodontic tooth movement. We detected sharp increases in the levels of p65*(536) 3 and 12 hrs after the application of orthodontic stimuli in rats. In cell culture, osteoclast-like cells displayed no changes in p65*(536) in response to RANK-L, but levels rapidly increased after the cells were mechanically scraped. We conclude that p65*(536) is produced rapidly in response to orthodontic stimuli and mechanical insults, and may be important in bone remodeling associated with orthodontic tooth movement.

Flow SS-PARSE: a new method for rapid imaging and mapping of blood flow velocity

A new method for flow velocity mapping of blood is presented here. Instead of the conventional approach of employing two images (velocity sensitive and control) to generate velocity information, in the new method the velocity is determined directly by solving an inverse problem. This technique is an application of single shot - parameter assessment by retrieval from signal encoding (SS-PARSE). Simulations have been done to demonstrate the feasibility of the method. The velocity measurement range of the prototype version is from -50cm/s to 50cm/s, roughly appropriate for future applications in blood flow measurement of carotid arteries.

Regulation of airway smooth muscle RhoA/ROCK activities by cholinergic and bronchodilator stimuli

The current study set out to compare the temporal relationships of Rho activity, Rho kinase (ROCK) activity and tone following cholinergic stimulation in the presence and absence of three different bronchodilators. Bovine trachea challenged with a half-maximally effective concentration of carbachol (CCh) was flash-frozen at different times, then assayed for Rho (rhotekin pull-down assay) and ROCK (Western blot; radiometric assay) activities. Rho was activated within 30 s, followed by ROCK (peak at 2 min); both returned to baseline by 20 min, although tone continued to rise over that period. Increasing the concentration of CCh greatly increased the magnitudes and rates of stimulation of Rho, ROCK and tone. These CCh-induced changes were next compared in tissues pre-treated with isoproterenol, salmeterol or the nitric oxide donor S-nitroso-N-acetylpenicillamine (SNAP). Neither the time course nor the magnitude of Rho-activation were reduced by the beta-agonists; SNAP slowed Rho activation but it did not alter the peak magnitude. These observations were mirrored in ROCK activation and contraction. When tissues were pre-constricted with CCh and then challenged with the bronchodilators, however, all three agonists reversed cholinergically stimulated Rho, ROCK and myosin light chain kinase activities as well as tone. In conclusion, bronchodilators can suppress RhoA and Rho kinase activities, although their major effect appears to be on myosin light chain kinase activity.

Study on performance of granular ANAMMOX process and characterization of the microbial community in sludge

Anaerobic Ammonium Oxidation (ANAMMOX) is a novel biological nitrogen removal process, which is regarded as the most economical process at present. In this paper, two lab-scale UASB reactors, one of which was inoculated with the mixture of anaerobic sludge and aerobic sludge, the other with river sediments, were started up, using the inorganic synthetic water containing ammonium and nitrite as influent. After 421 days' and 356 days operation respectively, the ammonium removal efficiencies in two reactors reached 94% and 86% respectively, the total nitrogen volumetric loading rates were 2.5 and 1.6 kgN/m3 x d. ANAMMOX granules were obtained in both reactors; the color of most granules was brown, but some of them were red. Based on the observation and studies on the microstructure of the granules, three kinds of ANAMMOX granular sludge formation mechanisms were proposed: adhering biofilm and disintegrated granular core mechanism, adhering biofilm and inorganic core mechanism and the self-coherence mechanism. For phylogenetic characterization of anaerobic ammonium oxidizers, 16S rDNA approach was performed using Planctomycetales-specific PCR amplification. The dominant anammox bacteria occupied more than 90% of Planctomycetales-specific bacteria, and 27% of all bacteria in reactors. The dominant anammox bacteria distantly related to all currently reported candidate anammox genera. Functional gene of amoA was analyzed to investigate the 'aerobic' ammonium-oxidizing bacteria in beta-Proteobacteria. The 'aerobic' ammonium-oxidizing bacteria were more diverse than anammox bacteria, but most of them clustered in anoxic ammonium-oxidizing Nitrosomonas eutropha/europaea groups. The composition of 'aerobic' ammonium-oxidizing bacteria is only 2% of all of bacteria in reactors.

Cochlear function in mice with only one copy of the prestin gene

Targeted deletion of the prestin gene reduces cochlear sensitivity and eliminates both frequency selectivity and outer hair cell (OHC) somatic electromotility. In addition, it has been reported by Liberman and colleagues that F2 generation heterozygotes exhibit a 6 dB reduction in sensitivity, as well as a decrease in protein and electromotility. Considering that the active process is non-linear, a halving of somatic electromotility would be expected to produce a much larger change in sensitivity. We therefore re-evaluated comparisons between heterozygotes and wildtype mice using both in vivo and in vitro electrophysiology, as well as molecular biology. Data reported here for F3-F5 generation mice indicate that compound action potential thresholds and tuning curves, as well as the cochlear microphonic, are similar in heterozygotes and wildtype controls. Measurements of non-linear capacitance in isolated OHCs demonstrate that charge density, as well as the voltage dependence and sensitivity of motor function, is indistinguishable in the two genotypes, as is somatic electromotility. In addition, both immunocytochemistry and western blot analysis in young adult mice suggest that prestin protein in heterozygotes is near normal. In contrast, prestin mRNA is always less than in wildtype mice at all ages tested. Results from F3-F5 generation mice suggest that one copy of the prestin gene is capable of compensating for the deleted copy and that heterozygous mice do not suffer peripheral hearing impairment.