Genetic tuning of the novel avian influenza A(H7N9) virus during interspecies transmission, China, 2013

A novel avian influenza A(H7N9) virus causing human infection emerged in February 2013 in China. To elucidate the mechanism of interspecies transmission, we compared the signature amino acids of avian influenza A(H7N9) viruses from human and non-human hosts and analysed the reassortants of 146 influenza A(H7N9) viruses with full genome sequences. We propose a genetic tuning procedure with continuous amino acid substitutions and reassorting that mediates host adaptation and interspecies transmission. When the early influenza A(H7N9) virus, containing ancestor haemagglutinin (HA) and neuraminidase (NA) genes similar to A/Shanghai/05 virus, circulated in waterfowl and transmitted to terrestrial poultry, it acquired an NA stalk deletion at amino acid positions 69 to 73. Then, receptor binding preference was tuned to increase the affinity to human-like receptors through HA G186V and Q226L mutations in terrestrial poultry. Additional mammalian adaptations such as PB2 E627K were selected in humans. The continual reassortation between H7N9 and H9N2 viruses resulted in multiple genotypes for further host adaptation. When we analysed a potential association of mutations and reassortants with clinical outcome, only the PB2 E627K mutation slightly increased the case fatality rate. Genetic tuning may create opportunities for further adaptation of influenza A(H7N9) and its potential to cause a pandemic.

Biomechanical changes in the pharynx and upper esophageal sphincter after modified balloon dilatation in brainstem stroke patients with dysphagia

BACKGROUND

Few studies have investigated the biomechanical changes in the upper esophageal sphincter (UES) and pharyngeal function after successful dilatation therapy for dysphagia. Using high-resolution manometry (HRM), we examined the biomechanical properties of swallowing in brainstem stroke patients with dysphagia following modified balloon dilation therapy.

METHODS

30 brainstem stroke patients with dysphagia were included. Patients in the experimental group received 3 weeks of modified balloon dilatation treatment and regular dysphagia therapy. Patients in the control group received 3 weeks of regular dysphagia therapy only. Efficacy of treatment was evaluated before and following intervention. Functional oral intake was measured using the Functional Oral Intake Scale (FOIS). Pharyngeal maximum pressures and duration, UES residual pressure and duration during swallowing were measured using HRM.

KEY RESULTS

In the experimental group, the feeding tube was able to be removed in 12 of 15 patients, vs 2 of 15 patients in the control group. The experimental group had 4-point median improvement, while control groups only had 1-point improvement in FOIS scores. In the experimental group, posttreatment UES relaxation and pharyngeal propulsion were both significantly improved for the three materials (p < 0.05) and UES resting pressure approximated normal. In the control group, pharyngeal propulsion was improved for water and thick liquids (p < 0.05) but not for paste material; there was no improvement in posttreatment UES relaxation for all three materials (p > 0.05).

CONCLUSIONS & INFERENCES

Dysphagia therapy with modified dilatation improved UES relaxation, strengthened pharyngeal propulsion, restored UES resting pressure and improved functional oral intake to a greater extent than regular therapy alone.

A set of microRNAs mediate direct conversion of human umbilical cord lining-derived mesenchymal stem cells into hepatocytes

In a previous study, we elucidated the specific microRNA (miRNA) profile of hepatic differentiation. In this study, we aimed to clarify the instructive role of six overexpressed miRNAs (miR-1246, miR-1290, miR-148a, miR-30a, miR-424 and miR-542-5p) during hepatic differentiation of human umbilical cord lining-derived mesenchymal stem cells (hMSCs) and to test whether overexpression of any of these miRNAs is sufficient to induce differentiation of the hMSCs into hepatocyte-like cells. Before hepatic differentiation, hMSCs were infected with a lentivirus containing a miRNA inhibitor sequence. We found that downregulation of any one of the six hepatic differentiation-specific miRNAs can inhibit HGF-induced hepatic differentiation including albumin expression and LDL uptake. Although overexpression of any one of the six miRNAs alone or liver-enriched miR-122 cannot initiate hepatic differentiation, ectopic overexpression of seven miRNAs (miR-1246, miR-1290, miR-148a, miR-30a, miR-424, miR-542-5p and miR-122) together can stimulate hMSC conversion into functionally mature induced hepatocytes (iHep). Additionally, after transplantation of the iHep cells into mice with CCL4-induced liver injury, we found that iHep not only can improve liver function but it also can restore injured livers. The findings from this study indicate that miRNAs have the capability of directly converting hMSCs to a hepatocyte phenotype in vitro.

Myocardial protection by Salvia miltiorrhiza Injection in streptozotocin-induced diabetic rats through attenuation of expression of thrombospondin-1 and transforming growth factor-β1

OBJECTIVES

To investigate the myocardially protective effects of Salvia miltiorrhiza injection in streptozotocin-induced diabetic rats and the possible mechanisms involved.

METHODS

Adult male Sprague-Dawley rats were randomized into three groups (n = 10 per group): diabetes, no treatment (Sm-); diabetes, S. miltiorrhiza injection (Sm+); control (no diabetes; saline treatment). After model induction and 4 weeks' treatment, heart function of five rats from each group was tested by Langendorff isolated in vivo heart perfusion. In the remaining rats, pathological changes of the myocardium were observed by haematoxylin and eosin staining, and protein levels of thrombospondin-1 (TSP-1) and transforming growth factor-β1 (TGF-β1) were assessed by immunohistochemistry.

RESULTS

Left ventricular systolic end pressure and left ventricular developed pressure were significantly improved in the Sm+ group compared with the Sm- group. Pathological changes were ameliorated through significantly reduced TSP-1 and TGF-β1 protein levels.

CONCLUSIONS

S. miltiorrhiza injection may improve the heart function of diabetic rats and protect against cardiomyopathy by downregulating TSP-1 and TGF-β1 in myocardial tissue.

Positive inotropic effect of PHR0007 (2-(4-(4-(Benzyloxy)-3-methoxybenzyl)piperazin-1-)-N-(1-methyl-4,5-dihydro[1,2,4]triazolo[4,3-a]quinolin-7-yl)acetamide) on atrial dynamics in beating rabbit atria

The aim of the present study was to examine the positive inotropic effects and mechanism of action of PHR0007 (2-(4-(4-(Benzyloxy)-3-methoxybenzyl)piperazin-1-)-N-(1-methyl-4,5-dihydro[1,2,4]triazolo[4,3-a]quinolin-7-yl)acetamide) on beating rabbit atria. Atria were obtained from New Zealand white rabbits, and experiments performed using a perfused beating atrial model. The effects of PHR0007 (1, 30, or 100 μmol/L), and of the protein kinase inhibitors, staurosporine (1.0 μmol/L) or H-89 (10 μmol/L), plus PHR0007 (30 μmol/L), on atrial pulse pressure and stroke volume were analyzed. PHR0007 significantly increased atrial pulse pressure and atrial stroke volume in beating rabbit atria compared with control baseline levels. These effects of PHR0007 were completely blocked by pretreatment with either staurosporine (a nonspecific protein kinase inhibitor) or H-89 (a cAMP-dependent protein kinase A inhibitor). In addition, 3-isobutyl-1-methylxanthine (IBMX), a non-specific inhibitor of phosphodiesterases (PDEs), completely blocked the positive inotropic effect of PHR0007 on atrial dynamics, but forskolin, an activator of adenylyl cyclases (AC), failed to modulate PHR0007-induced increases in atrial pulse pressure and stroke volume. In conclusion, these data suggest that PHR0007 produces a positive inotropic effect in rabbit atria via the PDE-cAMP-PKA signaling pathway.

Canopy penetration and deposition of barrier sprays from electrostatic and conventional sprayers

An experimental study was conducted to investigate the usefulness of electrostatic and conventional sprayers for barrier applications. Two conventional and three electrostatic sprayers were used in the study. Usefulness of the sprayers was rated based on penetration of spray into and deposition onto 2 sides of leaves on natural vegetation. Bifenthrin (Talstar adulticide) was applied at labeled rate, fluorescent dye was added to the tank mix as tracer, and all sprayers applied the dye and insecticide at the same rate. The results indicated that sprayers producing larger droplets produced significantly higher deposition on vegetation in barrier applications than the sprayers producing smaller droplets. Sprayers with higher air velocity at the nozzle discharge proved significantly better for barrier sprays than the sprayers with lower air velocity. Electrostatic sprayers did not show any improvement in deposition on vegetation or in penetration into vegetation over the conventional sprayers. There was no difference in deposition between truck-mounted and backpack sprayers.

Attention Deficit Hyperactivity Disorder in Children: Comparative Efficacy of Traditional Chinese Medicine and Methylphenidate

Traditional Chinese medicine (TCM) is frequently used to treat attention deficit hyperactivity disorders (ADHD) in children in China. However, until now there has been no strong evidence to prove that TCM has better efficacy than western medicine. In this systematic study of 34 studies published in the Chinese literature, the effectiveness of TCM in treating ADHD in children was examined and compared with methylphenidate (MPH), which is widely used to treat ADHD. It was found that TCM may have equal or better effectiveness than MPH. However, the lack of high-quality clinical trials to support this conclusion means that it is not currently possible to recommend any particular kind of TCM preparation for treating ADHD in children.

Spray characterization of thermal fogging equipment typically used in vector control

Droplet size spectra from different sprayers used to generate insecticide-laden fogs for controlling flying insects were measured by a laser diffraction instrument and Teflon-coated slides. The objectives of this work were to present not only information on spray-system droplet size generated by different sprayers, but to compare methodologies by which other similar systems can be evaluated and give applicators sprayer-system performance data. Data from 45 replicated spray tests, comprising 11 sprayers and 5 pesticides, showed a wide range in the droplet size spectra produced. The volume median diameter measurements ranged from 2.6 to 75.5 microm for diesel-diluted sprays and from 27.9 to 59.9 microm for water-diluted sprays. Similarly, the percent volume <20 microm ranged between 12.0-100% and 8.5-30.7%, for diesel- and water-diluted sprays, respectively. The droplet sizes measured by the swinging slide and laser diffraction methods were not consistent. The information presented aids users in sprayer selection and operation to produce the specific droplet size spectra required for a particular application.

Influence of complex reagents on removal of chromium(VI) by zero-valent iron

The removal of Cr(VI) by zero-valent iron (Fe(0)) and the effect of three complex reagents, ethylenediaminetetraacetic acid (EDTA), NaF and 1,10-phenanthroline, on this reaction were investigated using batch reactors at pH values of 4, 5 and 6. The results indicate that the removal of Cr(VI) by Fe(0) is slow at pH 5.0 and that three complex reagents play different roles in the reaction. EDTA and NaF significantly enhance the reaction rate. The zero-order rate constants at pH 5.0 were 5.44 microM min(-1) in the presence of 4mM EDTA and 0.99 micrM min(-1) in the presence of 8 mM NaF, respectively, whereas that of control was only 0.33 micrM min(-1), even at pH=4.0. This enhancement is attributed to the formation of complex compounds between EDTA/NaF and reaction products, such as Cr(III) and Fe(III), which eliminate the precipitates of Cr(III), Fe(III) hydroxides and Cr(x)Fe(1-)(x)(OH)(3) and thus reduce surface passivation of Fe(0). In contrast, 1,10-phenanthroline, a complex reagent for Fe(II), dramatically decreases Cr(VI) reduction by Fe(0). At pH=4.0, the zero-order rate constant in the presence of 1mM of 1,10-phenanthroline was 0.02 micrM min(-1), decreasing by 99.7% and 93.9%, respectively, compared with the results in the presence and absence of EDTA. The results suggest that a pathway of the reduction of Cr(VI) to Cr(III) by Fe(0) may involve dissolution of Fe(0) to produce Fe(II), followed by reduction of Cr(VI) by Fe(II), rather than the direct reaction between Cr(VI) and Fe(0), in which Fe(0) transfers electrons to Cr(VI).

Different effects of electroacupuncture on esophageal motility and serum hormones in cats with esophagitis

We aim to investigate the effects of different electroacupuncture (EA) frequencies at ST-36 on esophageal motility, and to compare the effect of EA on serum gastrin (GAS), motilin (MTL), and vasoactive intestinal peptide (VIP). Thirty-two cats were divided into four equal groups. All animals underwent a Heller myotomy. After esophagitis developed two frequencies (2/15 Hz or 2/100 Hz) of EA were delivered into ST-36 (LEA group [low EA], HEA group [high EA]). Animals submitted to EA on a non-point region (EANP) were used as controls (LEANP group, HEANP group), respectively. Esophageal motility was continuously monitored. The lower esophageal sphincter pressure (LESP) decreased significantly after myotomy. The LESP decreased in both LEA and LEANP cats, and in LEA cats the pressure decrease was greater. The LESP increased in the HEA group, which was higher than that in the HEANP group (P < 0.05). High-frequency EA significantly increased the peak amplitude in esophageal peristalsis. There was a decrease in serum GAS and MTL in LEA cats compared with LEANP cats (both P < 0.01). GAS and MTL were higher in the HEA group than in the HEANP group (both P < 0.01). Serum VIP decreased in the HEA group (P < 0.05), while it increased in the LEA group (P < 0.05), compared with EANP groups, respectively. EA with a high frequency at ST-36 enhances LESP as well as esophageal motility, while EA with a low frequency decreases LESP. The effect of EA is acupoint-specific, and this effect appears to be mediated through GAS, MTL and VIP.

Characterization of truck-mounted atomization equipment typically used in vector control

The control of medically important arthropod vectors of human and animal disease is a high priority for both public health and military officials. Because droplet size of pesticide spray material is a critical factor affecting vector control applications, the droplet-size spectra produced by 11 sprayers and 3 spray formulations were evaluated. Droplet-size spectra were measured by a laser diffraction instrument, a hot-wire system, and rotating slides. There were considerable differences in the droplet-size spectra produced by the different sprayers tested. The volume median diameter (Dv0.5) for the water-based sprays ranged from 4.7 to 211 microm, depending on the sprayer, and the percent of spray volume contained in droplets less than 20 microm (%vol <20 microm) ranged between 0.5% and 98.9%. The Dv0.5 measurements for the oil-based sprays ranged from 9.4 to 125.3 microm and the %vol <20 microm ranged between 2.4% and 97.9%. The correlations between the Dv0.5 measured by the laser system (Dv0.5-laser) and the mass median diameter, Sauter diameter, and Dv0.5 measured by the AIMS probe were all significant. Generally, the slide Dv0.5s were numerically similar to the Dv0.5 from the laser system and the Sauter diameter from the Army Insecticide Measuring System probe. There was less consistent agreement between the % <32 microm values obtained from the slides and those from the other 2 samplers. The information presented can be used by applicators to select the sprayer that produces the droplet-size spectra needed for their particular application situation.

Newton's descent method for the determination of invariant tori

We formulate a fictitious-time-flow equation which drives an initial guess torus to a torus invariant under a given dynamics, provided such a torus exists. The method is general and applies in principle to continuous time flows and discrete time maps in arbitrary dimension and to both Hamiltonian and dissipative systems.

Transcriptional profile of shrimp white spot syndrome virus (WSSV) genes with DNA microarray

In an attempt to obtain the transcriptional profile of shrimp white spot syndrome virus (WSSV) genes, DNA microarray analysis was performed using amplified DNA fragments of the WSSV genome that covered most of the presumptive open reading frames (ORFs). Total RNAs were extracted from WSSV-infected crayfish (Cambarus clarkii) and reverse transcribed into cDNA and labeled with 32P-dATP. The DNA microarray detected 81.1% of the ORFs, and 47 of these were transcribed at 6 h post infection, suggesting they may be early genes. Some early genes were further confirmed by temporal analyses of gene transcription. Results in this study indicated the effectiveness of DNA microarray for discovering early viral genes.