Morphological analysis and muscle-associated gene expression during different muscle growth phases of Megalobrama amblycephala

Skeletal muscle growth is regulated by both positive and negative factors, such as myogenic regulatory factors (MRFs) and myostatin (MSTN), and involves both hyperplasia and hypertrophy. In the present study, morphological changes during muscle development in Megalobrama amblycephala were characterized and gene expression levels were measured by quantitative real-time polymerase chain reaction (qRT-PCR) analysis in juvenile [60, 90, 120, and 180 days post-hatching (dph)] and adult fish. Our results show that during muscle development, the frequency of muscle fibers with a diameter <20 μm dramatically decreased in both red and white muscles, with a concomitant increase in the frequency of >30 μm fibers in red muscle and >50 μm fibers in white muscle. At 90-120 dph, the ratio of hyperplastic to hypertrophic areas in red and white muscles increased, but later decreased at 120-180 dph. The effect of hypertrophy was significantly larger than hyperplasia during these phases. qRT-PCR indicated MRF and MSTN (MSTNa and MSTNb) genes had similar expression patterns that peaked at 120 dph, with the exception of MSTNa. This new information on the molecular regulation of muscle growth and rapid growth phases will be of value to the cultivation of M. amblycephala.

Elevated Level of Circulating Platelet-derived Microparticles in Oral Cancer

Numerous studies have demonstrated that circulating microparticles (MPs) play important roles in a variety of diseases (e.g., atherosclerosis, hypertension, and diabetes), but the association between circulating MPs and oral squamous cell carcinoma (OSCC) remains largely unknown. In the present study, the circulating platelet-derived MPs (PMPs) in 63 patients with OSCC, 22 patients with infected keratocystic odontogenic tumor, and 31 healthy volunteers were characterized and quantified by flow cytometric analysis. The coagulation function of patients with OSCC was correspondingly evaluated. Meanwhile, the inflammation-related cytokines were detected in plasma by enzyme-linked immunosorbent assay and in tumor tissues by immunohistochemistry. Our results showed that the plasma level of circulating PMPs was significantly higher in OSCC patients compared with healthy volunteers and patients with infected keratocystic odontogenic tumor, and they showed positive correlation with the increased level of fibrinogen. Moreover, the coagulation time was significantly shorter after the MPs were added to the MP-free plasma. Most important, the levels of interleukin 6 and tumor necrosis factor α in plasma and tumor tissues were significantly increased in OSCC patients, which were closely correlated with the elevated level of circulating PMPs. In summary, this study suggests that the elevated level of circulating PMPs, showing close correlation with the secretion of inflammation-related factors, may contribute to the increased procoagulant activity in patients with OSCC.

Infections of nervous necrosis virus in wild and cage-reared marine fish from South China Sea with unexpected wide host ranges

The concerns about the impact of the nervous necrosis virus (NNV) infections in wild fish have been raised. This paper presents the results of quarterly surveys of NNV in wild and cage-reared marine fish from South China Sea. Samples of 892 wild fish belonging to 69 species and 381 cage-reared fish belonging to 11 species were collected and were detected by seminested PCR and nested PCR. In the case of seminested PCR, the positive signal was detected in 3.0% and 3.1% samples of wild and cage-reared fish, respectively. However, by nested RT-PCR, the positive signal was observed in 42.3% and 63.0% samples of wild and cage-reared fish, respectively. If the fish species were considered, the positive signal was detected in 21.7% and 72.7% species of wild and cage-reared fish by seminested PCR assay, respectively. However, by nested RT-PCR, the positive signal was observed in 65.2% and 100% species of wild and cage-reared fish, respectively. The nucleotide sequences of the nested PCR products were determined. Phylogenetic tree showed that all the obtained viral isolates belonged to the red-spotted grouper nervous necrosis virus (RGNNV) genotype. Thirty-five species of the marine fish were the new hosts of NNV.

Generation of quasi-monoenergetic electron beams with small normalized divergences angle from a 2 TW laser facility

We report the generation of a 6 pC, 23 MeV electron bunch with the energy spread ± 3.5% by using 2 TW, 80 fs high contrast laser pulses interacting with helium gas targets. Within the optimized experimental condition, we obtained quasi-monoenergetic electron beam with an ultra-small normalized divergence angle of 92 mrad, which is at least 5 times smaller than the previous LPA-produced bunches. We suggest the significant decrease of the normalized divergence angles is due to smooth transfer from SM-LWFA to LWFA. Since the beam size in LPA is typically small, this observation may explore a simple way to generate ultralow normalized emittance electron bunches by using small-power but high-repetition-rate laser facilities.

Plasmon hybridization in composite nanostructures with tunable resonances and vertex truncation analysis

An Ag/SiO₂/Ag sandwich delta nanostar with three sharp angles (30°) is proposed. The extinction efficiency property with a variation in environment refractive index has been investigated in detail by the finite difference time domain method. The refractive index response sensitivity is 482.67  nm/RIU. And the correlations between resonance wavelengths and thickness of the dielectric layer are also established. It reveals that as the thickness increases, the peak wavelength turns to red shift, and a tunable resonance wavelength is achieved through the thickness adjusting of the SiO₂ layer. The maximum of the electric field enhancement is 833.776 with the thickness of the dielectric layer h=40  nm. Moreover, the influence of the vertex truncation on the extinction spectra and the refractive index sensitivity has also been analyzed.

Effects of lovastatin on hepatic expression of the low-density lipoprotein receptor in nephrotic rats

To investigate the effect of the HMG-CoA reductase inhibitor lovastatin on the expression of the receptor for hepatic low-density lipoprotein (LDL) in a rat model with kidney disease, and to identify the mechanisms in statin treatment of nephrotic syndrome with hyperlipidemia, a rat model with nephrotic syndrome was established. Thirty male Sprague-Dawley rats were treated with lovastatin for 2 weeks using gavage. The expression of protein and mRNA of the LDL receptor in the rat liver was detected with Western blot and RT-PCR, respectively, and blood-biochemical indices were also recorded for each group. Compared with the untreated control group, lovastatin treatment significantly decreased the levels of serum total cholesterol, LDL cholesterol, triglycerides, and urinary protein. In addition, lovastatin treatment significantly increased the levels of serum albumin and hepatic LDL receptor proteins, but had no effect on the expression of hepatic LDL receptor mRNA. Treatment with lovastatin markedly increased the expression of the hepatic LDL receptor in rats with nephrotic syndrome, which was accompanied by significantly improved hyperlipidemia.

Association of the g.27563G>A osteoprotegerin genetic polymorphism with bone mineral density in Chinese women

Osteoporosis is a common multifactorial disease in postmenopausal women. This study aimed to investigate the association of the g.27563G>A osteoprotegerin (OPG) genetic polymorphism with bone mineral density (BMD) and osteoporosis. A case-control study was carried out with 435 osteoporosis postmenopausal women cases and 442 age-matched healthy controls. The BMD at the femoral neck hip, lumbar spine (L₂₋₄), and total hip were assessed by Norland XR-46 dual-energy X-ray absorptiometry. The genotypes of the g.27563G>A genetic polymorphism were detected by created restriction site-polymerase chain reaction and verified by DNA sequencing methods. We detected that the g.27563G>A genetic polymorphism was a non-synonymous mutation that resulted in an arginine (Arg) to glutamine (Gln) amino acid replacement (p.Arg333Gln). Significant differences were found in the BMD of the femoral neck hip, lumbar spine (L₂₋₄), and total hip among different genotypes of the g.27563G>A genetic polymorphism. Subjects with the genotype GG had significantly higher BMD values than those with genotypes GA and AA (P < 0.05). Our data indicated that the A allele of the g.27563G>A genetic polymorphism in OPG could be associated with lower BMD values in the Chinese postmenopausal women evaluated, and that it might be an increased risk factor for osteoporosis.

Species identification and evolutionary inference of the genera Megalobrama and Parabramis (Cyprinidae: Cultrinae) in China

The species boundaries and evolutionary relationships of two closely related genera, Megalobrama and Parabramis, were inferred from the partial mitochondrial cytochrome oxidase subunit I (COI) gene, NADH dehydrogenase subunit 2 (ND2) gene and their concatenated segment. Phylogenetic reconstructions showed that among the three breams, Megalobrama amblycephala and Megalobrama skolkovii are more closely related to each other than either is to Megalobrama terminalis. The taxonomy of M. pellegrini should be reconsidered. The divergence time estimation based on the assumption of a global molecular clock indicated that speciation and dispersal of the two genera might have occurred at approximately Pliocene to Late Pleistocene, due to major paleo-environmental events associated with monsoon evolution and the formation of the Three Gorges of the Yangtze River.

Note: A new angle-resolved proton energy spectrometer

In typical laser-driven proton acceleration experiments Thomson parabola proton spectrometers are used to measure the proton spectra with very small acceptance angle in specific directions. Stacks composed of CR-39 nuclear track detectors, imaging plates, or radiochromic films are used to measure the angular distributions of the proton beams, respectively. In this paper, a new proton spectrometer, which can measure the spectra and angular distributions simultaneously, has been designed. Proton acceleration experiments performed on the Xtreme light III laser system demonstrates that the spectrometer can give angle-resolved spectra with a large acceptance angle. This will be conductive to revealing the acceleration mechanisms, optimization, and applications of laser-driven proton beams.

An AFLP-based approach for the identification of sex-linked markers in blunt snout bream, Megalobrama amblycephala (Cyprinidae)

Sex-specific DNA markers are useful for studying sex-determination mechanisms and establishment of monosex populations. Three widely spaced geographical populations (Liangzi, Poyang and Yuni Lakes in China) of blunt snout bream (Megalobrama amblycephala) were screened with AFLPs to search for sex-linked markers. Female and male pools (10 individuals in each pool) from each population were screened using 64 different primer combinations. A total of 4789 genomic fragments were produced, with a mean frequency of 75 bands per primer pair. Three different primer combinations produced putative sex-associated amplifications and were selected for individual screening in the three populations. However, none showed sex specificity when we converted these three markers into sequence characterized amplified region markers and evaluated all the individuals from the three populations.

Inhibitory effects of rosiglitazone on lipopolysaccharide-induced inflammation in a murine model and HK-2 cells

BACKGROUND

Inflammation may play an important role in the pathogenesis of kidney disease. Agonists of the peroxisome proliferator-activated receptor-γ (PPAR-γ), such as rosiglitazone, have been recently demonstrated to regulate inflammation by modulating the production of inflammatory mediators. The purpose of this study was to examine the effects of rosiglitazone on lipopolysaccharide (LPS)-induced kidney inflammation and to explore the mechanism of its renoprotection.

METHODS

Mice were treated with LPS with or without pretreatment with rosiglitazone. Blood urea nitrogen (BUN), creatinine levels, the urinary albumin-to-creatinine ratio, macrophage infiltration, monocyte chemoattractant protein-1 (MCP-1) expression, PPAR-γ expression, and NF-κB and PPAR-γ activity were investigated. HK-2 cells were maintained under defined in vitro conditions, treated with either rosiglitazone and/or the PPAR-γ antagonist GW9662, and then stimulated with LPS. MCP-1, IL-8, IL-6, NF-κB activity and PPAR-γ expression were investigated.

RESULTS

Compared to the LPS only group, pretreatment with rosiglitazone in vivo significantly attenuated the BUN levels macrophage infiltration, MCP-1 overexpression and NF-κB activity (p < 0.05). Rosiglitazone also restored PPAR-γ expression and protein activity, which were reduced significantly in the LPS only group (p < 0.05). Furthermore, in the LPS-stimulated HK-2 cells, rosiglitazone downregulated MCP-1, IL-8 and IL-6 expression as well as NF-κB activation and increased PPAR-γ expression (p < 0.05). These effects were diminished by GW9662.

CONCLUSION

These results showed that pretreatment with rosiglitazone could attenuate kidney inflammation through the activation of PPAR-γ, suppression of MCP-1 overproduction and NF-κB activation. Rosiglitazone had a protective effect via a PPAR-γ-dependent pathway in LPS-treated HK-2 cells.

Intense high-contrast femtosecond K-shell x-ray source from laser-driven Ar clusters

Bright Ar quasimonochromatic K-shell x ray with very little background has been generated using an Ar clustering gas jet target irradiated with a 30 fs ultrahigh-contrast laser, with a measured flux of 2.2×10(11)   photons/J into 4π. This intense x-ray source critically depends on the laser contrast and intensity. The optimization of source output with interaction length is addressed. Simulations point to a nonlinear resonant mechanism of electron heating during the early stage of laser interaction, resulting in enhanced x-ray emission. The x-ray pulse duration is expected to be only 10 fs, opening the possibility for single-shot ultrafast keV x-ray imaging applications.

No sex-specific markers detected in bluegill sunfish Lepomis macrochirus by AFLP

The amplified fragment-length polymorphism (AFLP) technique was used to identify sex-specific markers in bluegill sunfish. A total of 12 835 loci were produced by 256 primer combinations, of which nine (0.73 per thousand) exhibited presumed sex-associated amplifications in the pooled samples; however, none of which revealed sex specificity upon individual evaluation.

First record of the natural occurrence of hexaploid loach Misgurnus anguillicaudatus in Hubei Province, China

Natural occurrence of hexaploid loach Misgurnus anguillicaudatus detected in central China is reported here for the first time. The evidences from karyotyping, DNA content analysis and nuclear volume measurements were described to confirm the hexaploid nature of the identified individual.

Histology and mucin histochemistry of the digestive tract of yellow catfish, Pelteobagrus fulvidraco

The histology and characteristics of mucins secreted by epithelial mucous cells of the digestive tract in yellow catfish, Pelteobagrus fulvidraco were investigated using light microscope and transmission electron microscope. The digestive tract was divided into a pharynx, oesophagus, U-shaped stomach (with a cardiac, fundic and pyloric part) and intestine, composed of anterior intestine, middle intestine and posterior intestine, which consisted of a mucosa (epithelial layer), lamina propria-submucosa, muscularis and serosa. A large number of isolated longitudinal striated muscular bundles were present in the lamina propria-submucosa of pharynx. Goblet cells were observed throughout the digestive tract, except in the stomach. In the cardiac and fundic stomach, a plenty of gastric glands were observed, whereas they were absent in the pyloric part. Numerous mitochondria and endoplasmic reticulum were observed in the columnar epithelial cells of the intestine, especially of the anterior part. The epithelial mucous cells contained neutral or other two mixtures of acid and neutral mucins, the first being the most common. The neutral mucin was the only type of mucins in the stomach, anterior intestine and middle intestine. The results of this study will be helpful for understanding the digestive physiology and diagnosing some gastrointestinal diseases in yellow catfish.

Single-cycle strong terahertz pulse generation from a vacuum-plasma interface driven by intense laser pulses

Single-cycle strong terahertz pulses can be generated by irradiating ultrashort intense laser pulses onto a tenuous plasma slab. At the plasma surface, laser ponderomotive force accelerates electrons and induces net currents, which radiate terahertz pulses. Our theoretical model suggests that if tau_{L}>2pi/omega_{p}, with tau_{L} as the laser-pulse duration and omega_{p} as the plasma frequency, the emission frequency is around tau_{L};{-1}. On the other hand, the emission frequency is around omega_{p}/2pi if tau_{L}<2pi/omega_{p}. Our numerical simulations support the theoretical model, showing that such a terahertz source is capable of providing megawatt power, field strengths of MV/cm, and broad frequency tunability.

Near-complete absorption of intense, ultrashort laser light by sub-lambda gratings

We demonstrate near-100% light absorption and increased x-ray emission from dense plasmas created on solid surfaces with a periodic sub-lambda structure. The efficacy of the structure-induced surface plasmon resonance, responsible for enhanced absorption, is directly tested at the highest intensities to date (3 x 10{15} W cm{-2}) via systematic, correlated measurements of absorption and x-ray emission. An analytical grating model as well as 2D particle-in-cell simulations conclusively explain our observations. Our study offers a definite, quantitative way forward for optimizing and understanding the absorption process.

Effect of target shape on fast electron emission in femtosecond laser-plasma interactions

Fast electron emission from the interaction of femtosecond laser pulses with shaped solid targets has been studied. It is found that the angular distributions of the forward fast electrons are highly dependent upon the target shapes. The important roles played by the electrostatic fields built up at the non-laser-irradiated target surfaces and the collisions in the target are identified. Our two-dimensional particle-in-cell simulations with binary collisions included reproduce the main experimental observations.

Randomized comparison of two rescue therapies for Helicobacter pylori infection

BACKGROUND

Bismuth salts are not available worldwide. It remains unknown whether clarithromycin can replace bismuth salts as an adjuvant agent in the rescue regimens for Helicobacter pylori infection. We therefore designed the prospective study to compare the efficacies of two rescue therapies for H. pylori infection after standard triple therapies.

PATIENTS AND METHODS

Ninety-three patients who failed H. pylori eradication using proton pump inhibitor plus clarithromycin and amoxicillin were randomly assigned to undergo rescue therapy with esomeprazole, clarithromycin, tetracycline and metronidazole (ECTM group, n = 46) or esomeprazole, bismuth subcitrate, tetracycline and metronidazole (EBTM group, n = 47). Follow-up endoscopy was performed at 8 weeks after the end of treatment to assess the treatment response.

RESULTS

Intention-to-treat analysis demonstrated both groups had similar eradication rates (ECTM 74% vs. EBTM 77%; P = 0.76) and drug compliance (ECTM 94% vs. EBTM 96%; P = 0.68). However, the frequency of adverse events in the ECTM group was higher than that in EBTM group (ECTM 57% vs. EBTM 36%, P = 0.05). In the EBTM group, eradication rate of metronidazole-resistant strains was lower than that of metronidazole-susceptible strains (67%[8/12] vs. 100%[9/9], P = 0.05). However, eradication rates were similar between metronidazole-susceptible and metronidazole-resistant strains in ECTM group (69%[9/13] vs. 70%[7/10], P = 1.00).

CONCLUSIONS

The new ECTM second-line therapy can achieve similar eradication rate as standard EBTM therapy. It may be very useful in countries where bismuth salts are not available.

TIMP-3 inhibits the procollagen N-proteinase ADAMTS-2

ADAMTS-2 is an extracellular metalloproteinase responsible for cleaving the N-propeptides of procollagens I-III; an activity necessary for the formation of collagenous ECM (extracellular matrix). The four TIMPs (tissue inhibitors of metalloproteinases) regulate the activities of matrix metalloproteinases, which are involved in degrading ECM components. Here we delineate the abilities of the TIMPs to affect biosynthetic processing of procollagens. TIMP-1, -2 and -4 show no inhibitory activity towards ADAMTS-2, in addition none of the TIMPs showed inhibitory activity towards bone morphogenetic protein 1, which is responsible for cleaving procollagen C-propeptides. In contrast, TIMP-3 is demonstrated to inhibit ADAMTS-2 in vitro with apparent Ki values of 160 and 602 nM, in the presence of heparin or without respectively; and TIMP-3 is shown to inhibit procollagen processing by cells.

Effects of selective brain cooling in patients with severe traumatic brain injury: a preliminary study

We prospectively investigated non-invasive selective brain cooling (SBC) in patients with severe traumatic brain injury. Sixty-six in-patients were randomized into three groups. In one group, brain temperature was maintained at 33 - 35 degrees C by cooling the head and neck (SBC); in a second group, mild systemic hypothermia (MSH; rectal temperature 33 - 35 degrees C) was produced with a cooling blanket; and a control group was not exposed to hypothermia. Natural rewarming began after 3 days. Mean intracranial pressure 24, 48 or 72 h after injury was significantly lower in the SBC group than in the control group. Mean serum superoxide dismutase levels on Days 3 and 7 after injury in the SBC and MSH groups were significantly higher than in the control group. The percentage of patients with a good neurological outcome 2 years after injury was 72.7%, 57.1% and 34.8% in the SBC, MSH and control groups, respectively. Complications were managed without severe sequelae. Non-invasive SBC was safe and effective.