Low-protein diet improves meat quality of growing and finishing pigs through changing lipid metabolism, fiber characteristics, and free amino acid profile of the muscle.

The objective of the study was to investigate the effect of feeding reduced CP, AA-supplemented diets on meat quality in growing and finishing pigs as well as the related mechanism. In experiment 1, 18 growing pigs (36.5 kg BW) were assigned randomly and fed 1 of 3 corn-soybean meal diets containing either 18% CP (normal protein, NP), 15% CP (low protein, LP), or 12% CP (very low protein, VLP). In experiment 2, 18 finishing pigs (62.3 kg BW) were allotted randomly into 1 of the following diets: 16% CP (NP), 13% CP (LP), or 10% CP (VLP). In both experiments, the LP and VLP diets were supplemented with crystalline AA to achieve equal content of standardized ileal digestible lysine, methionine, threonine, and tryptophan. At the end of each experiment, all pigs were slaughtered to collect longissimus dorsi muscle (LM) samples. Samples were used for determining meat quality, intramuscular fat (IMF) content, fatty acid composition, free AA profile, and expression of genes for myosin heavy chain isoforms. Results showed that growing and finishing pigs fed the LP diets increased (P < 0.05) redness value of LM, while finishing pigs fed the LP and VLP diets decreased (P < 0.05) the shear force values. Compared with the NP diet, growing and finishing pigs fed lower CP diets had higher (P < 0.05) contents of IMF and MUFA, and lower (P < 0.05) contents of PUFA. Besides, higher (P < 0.05) expression levels of type I and/or IIa muscle fibers were observed in LP diet-fed growing and finishing pigs, and greater concentrations of taurine and tasty AA in VLP diet-fed growing and finishing pigs. Taken together, our results indicate that low-protein diets could positively affect meat quality of growing and finishing pigs, and likely through regulation of IMF content and fatty acid composition, fiber characteristics, and free AA profile in the muscle.

Genome-wide association analysis reveals genomic regions on Chromosome 13 affecting litter size and candidate genes for uterine horn length in Erhualian pigs.

Litter size has a great impact on the profit of swine producers. Uterine development is an important determinant of reproduction efficiency and could hence affect litter size. Chinese Erhualian pig is one of the most prolific breeds in the world, even though large phenotypic variation in litter size was observed within Erhualian sows. To dissect the genetic basis of the phenotypic variation, we herein conducted genome-wide association studies for total number born and number born alive (NBA) of Erhualian sows. In total, one significant single nucleotide polymorphism (SNP) (P<1.78e-06) and 11 suggestive SNPs (P<3.57e-05) were identified on 10 chromosomes, confirming seven previously reported quantitative trait loci (QTL) and uncovering six QTL for litter size or uterus length. One locus on Sus scrofa chromosome (SSC) 13 (79.28 to 90.43 Mb) harbored a cluster of suggestive SNPs associated with multiparous NBA. The SNP (rs81447100) within this region was confirmed to be significantly (P<0.05) associated with litter size in Erhualian (n=313), Sutai (n=173) and Yorkshire (n=488) populations. Retinol binding protein 2 and retinol binding protein 1 functionally related to the development of uterus were located in a region of 2 Mb around rs81447100. Moreover, four genes related to embryo implantation and development were also detected around other significant SNPs. Taken together, our findings provide a potential marker (rs81447100) for the genetic improvement of litter size not only in Chinese Erhualian pigs but also in European commercial pig breeds like Yorkshire, and would facilitate the final identification of causative variant(s) underlying the effect of SSC13 QTL on litter size.

[Trends of asthma control, disease management and perception in China].

Objective: To evaluate the changes of asthma control, disease management and perception in recent years in China. Methods: We conducted 2 multi-center, cross-sectional surveys. Outpatient asthmatic patients from 10 cities in mainland China (2007-2008) and 30 central cities from 30 provinces in China (except Tibet)(2015-2016) were recruited respectively. Data of asthma control, disease management and perception from the 2 surveys were compared for 10 cities which took part in both of the 2 surveys. Chi-square test was used for comparison between groups. Results: The asthma control level improved from 28.7%(839/2 928) in 2007-2008 to 39.2%(533/1 361) in 2015-2016(P<0.01). The rate of emergency visits was 18.2%(248/1 362) in 2015-2016, which was lower than that in 2007-2008(33.9%, 1 032/3 044)(P<0.01). The rate of peak flow meter (PFM) usage was 17.9%(244/1 360) in 2015-2016, which was slightly lower than the PFM usage rate in 2007-2008(21.8%, 660/3 030)(P=0.004). 56.0%(763/1 362) of the patients used inhaled corticosteroid (ICS) + formoterol to control asthma when asthma symptoms deteriorated in 2015-2016, which was higher than the result of 2007-2008(31.8%, 803/2 524)(P<0.01). 71.1%(968/1 361) of the patients in 2015-2016 had a right perception on disease nature, while the result in 2007-2008 was 63.3%(1 889/2 986)(P<0.01). 61.6%(839/1 362) of the patients in 2015-2016 had a right perception on medication choice on daily-use first-line medication for chronic asthma, while the result in 2007-2008 was 51.0%(1 500/2 942)(P<0.01). Conclusion: The current level of asthma control and disease perception in China improved significantly in recent years, while the rate of PFM usage showed no significant improvement. Asthma action plan including PFM monitoring and asthma self-management should be further promoted nationwide.

Genotype and genetic variation of HCV infections with low-risk factors in Putian coastal regions, China.

Hepatitis C virus (HCV) infection is one of the leading causes of death and morbidity associated with liver disease. Risk factors identified for the transmission of HCV include contaminated blood products, intravenous drug use, body piercing, an infected mother at birth, sexual activity, and dental therapy, among others. However, the exact diversity of the HCV genotype and genetic variation among patients with low-risk factors is still unknown. In this study, we briefly described and analysed the genotype distribution and genetic variation of HCV infections with low-risk factors using molecular biology techniques. The results suggested that genotype 1b was predominant, followed by genotypes 2a and 1a. Genetic variations in the 5' UTR sequences of HCV were identified, including point mutations, deletions, and insertions. The frequency of genetic variations in 1b was higher than in 2a. This study provides considerable value for the prevention and treatment of liver disease caused by HCV among patients with low-risk factors and for the development of HCV diagnostic reagents and vaccines.

A novel laser-collider used to produce monoenergetic 13.3 MeV (7)Li (d, n) neutrons.

Neutron energy is directly correlated with the energy of the incident ions in experiments involving laser-driven nuclear reactions. Using high-energy incident ions reduces the energy concentration of the generated neutrons. A novel "laser-collider" method was used at the Shenguang II laser facility to produce monoenergetic neutrons via (7)Li (d, n) nuclear reactions. The specially designed K-shaped target significantly increased the numbers of incident d and Li ions at the keV level. Ultimately, 13.3 MeV neutrons were obtained. Considering the time resolution of the neutron detector, we demonstrated that the produced neutrons were monoenergetic. Interferometry and a Multi hydro-dynamics simulation confirmed the monoenergetic nature of these neutrons.

Neutron yield enhancement in laser-induced deuterium-deuterium fusion using a novel shaped target.

Neutron yields have direct correlation with the energy of incident deuterons in experiments of laser deuterated target interaction [Roth et al., Phys. Rev. Lett. 110, 044802 (2013) and Higginson et al., Phys. Plasmas 18, 100703 (2011)], while deuterated plasma density is also an important parameter. Experiments at the Shenguang II laser facility have produced neutrons with energy of 2.45 MeV using d (d, n) He reaction. Deuterated foil target and K-shaped target were employed to study the influence of plasma density on neutron yields. Neutron yield generated by K-shaped target (nearly 10(6)) was two times higher than by foil target because the K-shaped target results in higher density plasma. Interferometry and multi hydro-dynamics simulation confirmed the importance of plasma density for enhancement of neutron yields.

Dynamic changes in TAP1 expression levels in newborn to weaning piglets, and its association with Escherichia coli F18 resistance.

The transporter associated with antigen processing (TAP) transports peptides from the cytosol into the endoplasmic reticulum for subsequent loading onto the major histocompatibility complex (MHC) class I molecules. This study showed the dynamic changes in the TAP1 expression level in newborn to weaning piglets. Tissue expression profiles revealed that the TAP1 gene was expressed at low levels in all tissues, and the expression levels were relatively higher in the lung, spleen, lymph, and thymus; further, no significant difference was observed in the expression in each tissue among the 3 unweaned stages (8, 18, and 30 days). Nevertheless, the postweaning (35 days) expression levels in tissues, including the spleen, lung, lymph, duodenum, and jejunum were significantly higher than those in the unweaned stages. Furthermore, gene ontology and pathway analysis showed that TAP1 took part in 38 biological functions and 5 pathway processes, including ABC transporters and antigen processing and presentation. These analyses showed that the TAP1 gene, which was related to MHC I immune regulation, had a stable and low expression level in unweaned stages; however, its expression increased in the postweaning stages. The high expression level of TAP1 indicated that the gene might play an important role in Escherichia coli F18 resistance.

TLR4 gene expression in pig populations and its association with resistance to Escherichia coli F18.

TLR4 is the main recognition receptor of bacterial lipopolysaccharides, which play an important role in innate and adaptive immunity. We used real-time PCR to analyze the tissue expression profile and differential expression of TLR4 in 4 pig populations (Escherichia coli F18-resistant Sutai, E. coli F18-sensitive Sutai, Large White, Meishan), in order to determine the role that the TLR4 gene plays in resistance to E. coli F18. We found that TLR4 expressed consistently in the 4 populations, with relatively high levels in immune tissues and the highest level in the lung. Generally, the expression of TLR4 in E. coli F18-sensitive individuals was the highest, followed by that in E. coli F18-resistant, Large White and Meishan. In the spleen, lung, kidney, lymph nodes, and thymus gland, TLR4 expression is significantly higher in the E. coli F18-sensitive than in the other 3 populations; there were no significant differences among E. coli F18-resistant Sutai, Large White, and Meishan. In addition, Gene Ontology and pathway analysis showed that TLR4 takes part in the inflammatory response. We found that porcine TLR4 has consistent tissue specificity in each breed, and downregulation of expression of the TLR4 gene is related to resistance to E. coli F18 in weaning piglets.

Age-dependent expression of the BPI gene in Sutai piglets.

We compared and analyzed the expression of the BPI gene of Sutai piglets ranging from newborn to post-weaning days 8, 18, 30, and 35 by the real-time PCR method, in order to determine if it is involved in protection against disease caused by ETEC F18. There was a significant difference between 18 and 35-day expression in the jejunum. There were also significant differences between 35-day expression and expression at the other development stages in the duodenum. There were no significant differences in expression at 8, 18, and 30 days in the jejunum. We conclude that the porcine BPI gene may be the direct factor that resisted the ETEC F18 in weaning piglets, and that the resistance to ETEC F18 in weaning piglets is related to up-regulation of mRNA expression of BPI gene to a certain extent.

Microarray analysis of differential gene expression in sensitive and resistant pig to Escherichia coli F18.

In this study, Agilent two-colour microarray-based gene expression profiling was used to detect differential gene expression in duodenal tissues collected from eight full-sib pairs of Sutai pigs differing in adhesion phenotype (sensitivity and resistance to Escherichia coli F18). Using a two-fold change minimum threshold, we found 18 genes that were differentially expressed (10 up-regulated and eight down-regulated) between the sensitive and resistant animal groups. Our gene ontology analysis revealed that these differentially expressed genes are involved in a variety of biological processes, including immune responses, extracellular modification (e.g. glycosylation), cell adhesion and signal transduction, all of which are related to the anabolic metabolism of glycolipids, as well as to inflammation- and immune-related pathways. Based on the genes identified in the screen and the pathway analysis results, real-time PCR was used to test the involvement of ST3GAL1 and A genes (of glycolipid-related pathways), SLA-1 and SLA-3 genes (of inflammation- and immune-related pathways), as well as the differential genes FUT1, TAP1 and SLA-DQA. Subsequently, real-time PCR was performed to validate seven differentially expressed genes screened out by the microarray approach, and sufficient consistency was observed between the two methods. The results support the conclusion that these genes are related to the E. coli F18 receptor and susceptibility to E. coli F18.

Investigation of the relationship between SLA-1 and SLA-3 gene expression and susceptibility to Escherichia coli F18 in post-weaning pigs.

Porcine post-weaning diarrhea and edema disease are principally caused by Escherichia coli strains that produce F18 adhesin. FUT1 genotyping and receptor binding studies divided piglets into E. coli F18-resistant and -sensitive groups, and the roles of SLA-1 and SLA-3 were investigated. SLA-1 and SLA-3 expression was detected in 11 pig tissues, with higher levels of SLA-1 in lung, immune tissues and gastrointestinal tract, and higher levels of SLA-3 also in lung and lymphoid tissues. Both genes were expressed higher in F18-resistant piglets, and their expression was positively correlated in different tissues; a negative correlation was observed in some tissues of F18-sensitive group, particularly in lung and lymphatic samples. Gene ontology and pathway analyses showed that SLA-1 and SLA-3 were involved in 37 biological processes, including nine pathways related to immune functions. These observations help to elucidate the relationship between SLA class I genes and E. coli F18-related porcine gastrointestinal tract diseases.

Polymorphism of M307 of the FUT1 gene and its relationship with some immune indexes in Sutai pigs (Duroc x Meishan).

The alpha (1,2)fucosyltransferase (FUT1) gene has been identified as a candidate gene for controlling the expression of the enterotoxigenic Escherichia coli (ETEC) F18 receptor. Polymorphisms were detected at the M307 position in FUT1 of a breeding base population of Sutai pigs and their correlations to immune parameters analyzed. After digestion by Hin6I, three genotypes were identified at M307, AA (frequency 0.235), AG (0.609), and GG (0.156), with significant deviation from Hardy-Weinberg equilibrium (P < 0.01). The hemoglobin and white blood cell count of the AA genotype pigs were significantly higher than those of AG and GG pigs (P < 0.05). The results indicated that AA pigs not only are resistant to edema disease and post-weaning diarrhea in piglets but also have relatively strong resistance to disease in general.

Behavioral and neurochemical characterization of transgenic mice carrying the human presenilin-1 gene with or without the leucine-to-proline mutation at codon 235.

Human presenilin-1 (PS1) mutations are associated with the incidence of familial Alzheimer's disease. The present study evaluated the behavioral and neurochemical effects of the L235P mutation (substitution of leucine by proline at codon 235) of the human PS1 gene, which has been linked to a form of early-onset Alzheimer's disease. Except for a significant increase in the production of beta-amyloid-42, the mutant mice did not show any overt signs of Alzheimer-like neuropathology in the form of plaque formation, changes in choline acetyltransferase activity, or somatostatin content in the brain. Cognitive assays indicated that the mutation did not affect the acquisition or reversal of a spatial reference memory task in the water maze or performance on a spatial working memory task. In contrast, L235P PS1 transgenic mice exhibited a significant impairment in a test of spontaneous object recognition. This dissociation is suggestive of a preferential impairment of the extrahippocampal memory system and is consistent with what has been reported in another pathological mutation (substitution of leucine by valine at codon 286) of the PS1 gene.

[Clinical evaluation of frozen-phalanx-joint-tendon-sheath composite tissue allograft].

OBJECTIVE: To evaluate clinical result of reconstructed thumb and finger with a free hallux nail flap(HNF) and frozen-phalanx-joint-tendon-sheath composite tissue allograft in 270 cases. METHODS: The patients were followed up with reexamination in the ambulant clinic, communication, X-ray photography, lab-examination, isotope 99mTc MDP and reoperation. The data were analyzed by statistics or proved by clinical observation, which were followed up for five years in average (ranging from five months to sixteen years). RESULTS: Enveloping the allogeneic finger composite tissue with self-HNF and pieces of phalanx of great toe, it could reconstruct a thumb or finger with good contour and nutrition. The excellent rate of opposition function of the reconstructed thumbs was 71.91%. The sense of the fingers recovered after 3 months to 8 months of operation. Two-point discrimination was 3 mm to 15 mm. The junction between implanted allo-phalanges and auto-phalanges could be hastened by implanted with vascularized autogenous phalanx pieces in the HNF. The isotope 99mTc MDP was used to take X-ray photography in 24 cases for four months to 9 years and seven months, which showed that the blood vessels grew into the allo-phalanges. However, the Charcot's arthropathy of allogeneic joints and bony absorption still could be seen in some cases. That might be concerned with chronic abrasion of joint or chronic rejection of host to graft. CONCLUSION: The operation is fit for repairing the defect of thumb or finger in any degree. The implanted vascularized self-phalanx pieces can promote bone union, but it can not prevent the allogeneic joints from arthropathy or bone absorption.

[Repair of flexor-tendon injury in children's finger using microsurgical technique].

OBJECTIVE: To improve the clinical result of repair on flexor tendon injury, and recover the defected finger function in children as far as possible. METHODS: From January 1990 to October 1997, 12 cases with flexor tendon injury were repaired by microsurgical technique, sutured by modified Kessler method with 3/0 or 5/0 nontraumatic thread and followed by invering suture of the gap edge with 7/0 or 8/0 nontraumatic thread after debridement. Appropriate functional practice was performed postoperatively. RESULTS: All the defected fingers were healed by first intention. Followed up 6 months to 1 year, there was excellent in 7 cases, better in 4 cases, moderate in 1 case and 91.67% in excellent rate according to the TAM standard of International Hand Committee. CONCLUSION: The important measures to improve the clinical result in children's flexor tendon injury are prompt and accurate diagnosis and repair of the injured tendon by microsurgical technique, and effective postoperative functional practice.

Subwavelength-resolvable focused non-gaussian beam shaped with a binary diffractive optical element.

The diffraction-limited spot size limits the optical disk storage capacity and microscopic resolution. We describe a technique to shape a focused Gaussian beam into a superresolving beam by using a diffractive optical element fabricated by laser-assisted chemical etching. The focused shaped beam has a smaller width and a longer depth of focus than a similarly focused Gaussian beam. Using the diffraction-limited shaped beam along with threshold writing, we achieved a written pit size of less than 0.33 microm at a 695-nm laser wavelength, compared with a 0.7-microm focused Gaussian spot size (full width at e(-2) of the peak) with the same focusing lens. The energy conversion efficiency for the beam shaping was approximately 81%.

Low-threshold lasing of a Rhodamine dye solution embedded with nanoparticle fractal aggregates.

The spectral and temporal emission properties of a Rhodamine (Rh) dye solution embedded with nanoparticle fractal aggregates are studied. An experiment on the pump-power density dependence of Rh emission spectra shows that the lasing threshold of a Rh6G solution embedded with TiO(2) nanoparticle fractal aggregates is significantly reduced compared with that of a neat dye solution. The mechanism of this reduction in lasing threshold is discussed, together with the lasing properties of narrow bandwidth and short duration.

Generation of frequency-tunable ultrashort optical pulses with liquid-core fibers.

Experimental generation of ultrashort, frequency-tunable optical pulses in liquid-core fibers is reported. Passage of high-energy optical pulses through a submillimeter liquid-core fiber reveals a quasi-linear frequency sweep. The subsequent use of a grating dispersion system and a spectral window shortens the Nd:YAG laser pulse duration from 45 ps to less than 2 ps. Based on spectral filtering after the grating pair, the wavelength of the generated short pulses is shown to be tunable.