Changes in physical architecture and lipids compounds in skeletal muscle from Pekin duck and Liancheng white duck.

As a complex food, meat displays various biochemical properties that are determined to a great extent by physical architecture and lipid metabolites. Pekin duck and Liancheng white duck are elite breeds with distinct characteristics. Here, we explored the development of the muscle fibers from embryonic stage to 10-wk after birth, and muscle fibers grow slowly after 8-wk. We investigated the meat quality, ultrastructure, lipidomics profiling, and lipids spatial distribution of skeletal muscle at 8 wk. Pekin duck has lower Warner-Bratzler shear force (WBSF) (P < 0.05), high intramuscular fat (IMF) (P < 0.01), longer and wider sarcomere, and higher mitochondrial density (P < 0.001). Liancheng white duck with tighter collagen architecture. A total of 950 lipids from 6 lipid classes identified with lipidomics were analyzed, the levels of GP, GL, and PR were significantly higher in Pekin duck (P < 0.05), SL and ST were significantly higher in Liancheng white duck (P < 0.05). There were 333 significantly different lipids (|log2(Fold Change)| ≥ 1 and FDR < 0.05) screened, most lipids distributed in the muscle tissue were uniform, but some specifically distributed in connective tissue. To some extent, the results demonstrate the high lipid deposition capacity of Pekin duck and the high medicinal function of Liancheng white duck. Our study provides new insights into the relationship between skeletal muscle architecture and meat toughness, which increased the knowledge of lipidomic characteristics and provide a basis for duck meat authentication.

Recycling hazardous textile effluent sludge in cement-based construction materials: Physicochemical interactions between sludge and cement.

The textile industry produces a large amount of textile effluent sludge (TES). Many studies have explored the potential use of TES in cement-based materials. However, the physicochemical interactions between the TES and ordinary Portland cement (OPC) have rarely been studied. In this study, the effects of increasing dosage (0-20% by OPC) of TES on the performance of OPC-TES blends were investigated in terms of hydration progress, mechanical strength, microstructure evolution and metal leachability. The results showed that TES markedly delayed the OPC hydration at the early age, and increasing dosages of TES decreased the portlandite content at 7 and 28 days' age. Compared to the reference, the OPC-TES mortar exhibited seriously degraded mechanical strength; when using 20% TES, the decrease in compressive and flexural strength reached up to 71% and 42% respectively at the age of 28 days. Scanning electron microcopy and mercury intrusion porosimetry found the inclusion of TES introduced more weak interfaces in the cement mortar, thus increased the total porosity especially the macropores. But leachability tests revealed all the toxic metals in the TES were stabilized after the incorporation of OPC and exhibited very low metal mobility in the OPC-TES mortar, which posed no environmental risk.

Identification of UHRF2 as a novel DNA interstrand crosslink sensor protein.

The Fanconi Anemia (FA) pathway is important for repairing interstrand crosslinks (ICLs) between the Watson-Crick strands of the DNA double helix. An initial and essential stage in the repair process is the detection of the ICL. Here, we report the identification of UHRF2, a paralogue of UHRF1, as an ICL sensor protein. UHRF2 is recruited to ICLs in the genome within seconds of their appearance. We show that UHRF2 cooperates with UHRF1, to ensure recruitment of FANCD2 to ICLs. A direct protein-protein interaction is formed between UHRF1 and UHRF2, and between either UHRF1 and UHRF2, and FANCD2. Importantly, we demonstrate that the essential monoubiquitination of FANCD2 is stimulated by UHRF1/UHRF2. The stimulation is mediating by a retention of FANCD2 on chromatin, allowing for its monoubiquitination by the FA core complex. Taken together, we uncover a mechanism of ICL sensing by UHRF2, leading to FANCD2 recruitment and retention at ICLs, in turn facilitating activation of FANCD2 by monoubiquitination.

Genetic parameters for residual feed intake in a random population of Pekin duck.

OBJECTIVE: The feed intake (FI) and feed efficiency are economically important traits in ducks. To obtain insight into this economically important trait, we designed an experiment based on the residual feed intake (RFI) and feed conversion ratio (FCR) of a random population Pekin duck. METHODS: Two thousand and twenty pedigreed random population Pekin ducks were established from 90 males mated to 450 females in two hatches. Traits analyzed in the study were body weight at the 42th day (BW42), 15 to 42 days average daily gain (ADG), 15 to 42 days FI, 15 to 42 days FCR, and 15 to 42 days RFI to assess their genetic inter-relationships. The genetic parameters for feed efficiency traits were estimated using restricted maximum likelihood (REML) methodology applied to a sire-dam model for all traits using the ASREML software. RESULTS: Estimates heritability of BW42, ADG, FI, FCR, and RFI were 0.39, 0.38, 0.33, 0.38, and 0.41, respectively. The genetic correlation was high between RFI and FI (0.77) and moderate between RFI and FCR (0.54). The genetic correlation was high and moderate between FCR and ADG (-0.80), and between FCR and BW42 (-0.64), and between FCR and FI (0.49), respectively. CONCLUSION: Thus, selection on RFI was expected to improve feed efficiency, and reduce FI. Selection on RFI thus improves the feed efficiency of animals without impairing their FI and increase growth rate.

UHRF1 is a sensor for DNA interstrand crosslinks and recruits FANCD2 to initiate the Fanconi anemia pathway.

The Fanconi anemia (FA) pathway is critical for the cellular response to toxic DNA interstrand crosslinks (ICLs). Using a biochemical purification strategy, we identified UHRF1 as a protein that specifically interacts with ICLs in vitro and in vivo. Reduction of cellular levels of UHRF1 by RNAi attenuates the FA pathway and sensitizes cells to mitomycin C. Knockdown cells display a drastic reduction in FANCD2 foci formation. Using live-cell imaging, we observe that UHRF1 is rapidly recruited to chromatin in response to DNA crosslinking agents and that this recruitment both precedes and is required for the recruitment of FANCD2 to ICLs. Based on these results, we describe a mechanism of ICL sensing and propose that UHRF1 is a critical factor that binds to ICLs. In turn, this binding is necessary for the subsequent recruitment of FANCD2, which allows the DNA repair process to initiate.

A luminescent cyclometalated iridium(III) complex accumulates in mitochondria and induces mitochondrial shortening by conjugation to specific protein targets.

We report the cellular properties of a luminescent cyclometalated iridium(III) complex, [Ir(pq)(2)(phen-ITC)](PF(6)) (Ir-ITC; Hpq=2-phenylquinoline, phen-ITC=5-isothiocyanate-1,10-phenanthroline), that efficiently and specifically labels mitochondria in living mammalian cells. Ir-ITC can be covalently conjugated to its protein targets, and its luminescence survived cell lysis, protein extraction, and gel electrophoresis under denaturing conditions. The conjugation of Ir-ITC with live-cell proteins is rapid and highly selective; the process requires active cellular metabolism, as the conjugation is abolished at nonphysiological temperature or in the presence of sodium azide. Based on measurements of the luminescence intensity, we have devised a biochemical fractionation procedure that allows the enrichment of the conjugated proteins, and their subsequent separation by two-dimensional gel electrophoresis (2DGE). Luminescent protein spots were picked from the gel and analyzed by mass spectrometry; this resulted in the identification of 46 proteins. Many of the strongly luminescently labeled proteins are mitochondrial proteins. One of the targets is VDAC1 (voltage-dependent anion channel 1). Consistent with known phenotypes of VDAC1 deregulation, prolonged exposure of cells to Ir-ITC led to significant mitochondrial shortening and fragmentation. As far as we know, this is the first report on the molecular characterization of the interactions of a luminescent dye with its biological targets. As many biological dyes exhibit specific intracellular staining patterns, the identification of their molecular targets can help elucidate the mechanisms behind their staining specificities and cytotoxicity. We believe our biochemical approach can be applied to identify the targets of a wide range of fluorescent and luminescent probes.

[Foraging behavior and pollination ecology of Bombus lucorum L. and Apis mellifera L. in greenhouse peach garden].

From 2004 to 2006, this paper studied the foraging behavior and pollination ecology of two Chinese bee species Bombus lucorum L. and Apis mellifera L. in greenhouse peach garden in Beijing. The results showed that both of the bee species were able to substitute manual work to provide effective pollination, but their foraging behavior and pollination effect differed significantly in terms of their working timing and visiting frequency, temperature, and the location of flowers on peach tree. B. lucorum L. preferred to collect pollen and release it mainly by vibrating their wings, while A. mellifera L. gathered and released pollen mainly through body touch on flowers. Moreover, B. lucorum L. could work at lower temperature and visit more flowers each day, while the activities of A. mellifera L. were easily affected by weather conditions including sunlight and temperature. It was often found that A. mellifera L. bumped itself on greenhouse ceiling because of its strong photokinesis.

[Analysis of relationship between semen quality and sperm acrosin activity].

OBJECTIVE: To analyze the activity of human sperm acrosin and semen parameters in male infertile patients and discuss the effect of sperm acrosin activity on semen quality. METHODS: Activity of human sperm acrosin, PMN-elastase, fructose, alpha-glucosidase, zinc, acid phosphatase levels and HOST of 214 male infertile patients were detected. Semen analysis was performed using WLJY-9000 WeiLi colorful semen quality analyzer. There were 111 cases of normal activity of human sperm acrosin (48.2 - 218.7 microIU/10(6) sperm), 103 cases abnormal (< 48.2 microIU/10(6) sperm). Using the group of normal activity of sperm acrosin to be the control, semen parameters was analyzed and compared with those of the group of abnormal activity of sperm acrosin. RESULTS: There were significant difference (P < 0.001) between the 2 groups (normal and abnormal) in the areas of sperm density, motile sperm rate, percentage of grade (a + b) sperm and HOST. There were also significant difference in PMN-elastase, fructose and alpha-glucosidase (P < 0.05). There was no difference among sperm volume, zinc and acid phosphatase (P > 0.05). CONCLUSION: There was a strong correlation between the activity of human sperm sperm acrosin and semen quality. Activity of sperm acrosin is a reliable index of semen quality.

[Determination of 14 trace elements in soybean and its products by atomic absorption spectrometry].

Fourteen trace elements in soybean and its products were determined by atomic absorption spectrometry. The effects of cinefaction temperature, cinefaction time, and the concentration of HNO3 as a digestion solution were investigated in detail. The effect of the concentration of SrCl2 on the determination of Ca and Mg was also studied. The results obtained show that the soybean and its products contain higher amounts of K, Na, Ca, Mg, Fe, Cu, Zn and Mn than other elements.