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The cuticle formed in the uterus is the outermost layer as the first defense line of eggshell against microbial invasions in most avian species, and analyzing its genetic regulation and influencing factors are of great importance to egg biosecurity in poultry production worldwide. The current study compared the uterine transcriptome and proteome of laying hens producing eggs with good and poor cuticle quality (GC and PC, the top and tail of the cuticle quality distribution), and identified several genes involved with eggshell cuticle quality (ESCQ). Overall, transcriptomic analysis identified 53 differentially expressed genes (DEGs) between PC versus GC group hens, among which 25 were up-regulated and 28 were down-regulated. No differences were found in the uterine proteome. Several DEGs, including PTGDS, PLCG2, ADM and PRLR related to uterine functions and reproductive hormones, were validated by qPCR analysis. Egg quality measurements between GC and PC hens showed GC hens had longer laying interval between two consecutive ovipositions (25.64 ± 1.23 vs 24.94 ± 1.12 h) and thicker eggshell thickness (352.01 ± 23.04 vs 316.20 ± 30.58 μm) (P < 0.05). Apart from eggshell traits, other egg quality traits didn't differ. The result demonstrated eggshell and cuticle deposition duration in the uterus is one of the major factors affecting ESCQ in laying hens. PTGDS, PLCG2, ADM and PRLR genes were discovered and might play crucial roles in cuticle deposition by regulating the uterine muscular activities and secretion function. The findings in the present study provide new insights into the genetic regulation of cuticle deposition in laying hens and establish a foundation for further investigations. [ABSTRACT FROM AUTHOR]

An efficient and eco-friendly protocol for the construction of naphtho[2,1-d]thiazol-2-amines through visible-light photoredoxcatalyzed C(sp2)-H/S-H cross-dehydrogenative coupling reactions between 2-isothiocyanatonaphthalenes and amines was established. In this reaction, the new C-N and C-S bonds are formed simultaneously in a single step. This new method provides a straightforward approach for constructing valuable sulfur-containing compounds. [ABSTRACT FROM AUTHOR]

Water-soluble Cu nanoclusters (NCs) with tunable emission were synthesized through an eco-friendly one-pot aqueous method. Blue-, green-, and red-emitting NCs with the emission peaks at 420 nm, 505 nm, and 630 nm were obtained by employing ethanediamine, cysteine, and glutathione as surface ligands, respectively. The ligand effects on the optical properties of Cu NCs were studied by the single variable method. It has been revealed by systematic characterizations that the dependence of emission color on the structures of ligands was mainly attributed to their different size-tuning effects. Glutathione has the strongest chelating ability and it can significantly reduce the monomer reactivity and thus decrease the supersaturation degree of the reaction, which is favorable for modulating Cu precursor to grow into larger NCs. In contrast, ethanediamine ligand resulted in smaller nanoclusters due to its weaker binding capability. Because of the strong emission and terrific fluorescent stability, Cu NCs capped with ethanediamine, possessing an emission peak at 420 nm when excited at a wavelength of 350 nm, were directly used for probing Hg(II) with satisfying selectivity, presenting a linear range of 0.1–5.0 mM and a detection limit of 33 μM. The sensor showed good performance in real sample analysis with recoveries ranging from 99% to 103%, and comparable accuracy with atomic fluorescence spectroscopy, manifesting the reliability of the current strategy for sensing Hg(II). [ABSTRACT FROM AUTHOR]

Carboxylated cellulose nanocrystals (CNCC) were synthesized by treating microcrystalline cellulose with ammonium persulfate. Silver nanoparticles (AgNPs) were prepared on the surface of CNCC using NaBH as reductant. Novel conducting nanocomposites of poly(3,4-ethylenedioxythiophene) (PEDOT) doped with AgNPs/CNCC were electrodeposited on the surface of the glassy carbon electrode. The nanocomposites prepared in various ratios of PEDOT, CNCC, and AgNPs were characterized by scanning electron microscopy, transmission electron microscope, electrochemical impedance spectroscopy, cyclic voltammetry, and differential pulse voltammetry. The prepared PEDOT/AgNPs/CNCC showed much low electrochemical impedance and very good response towards the oxidation of dopamine. Based on these findings, a highly stable, sensitive, and selective amperometric sensor for the detection of dopamine was developed. Operated at 0.20 V (vs. Ag/AgCl), the sensor can detect dopamine in the range of 0.05 to 782 μM with a 17-nM detection limit. [ABSTRACT FROM AUTHOR]

Poly(3,4-ethylenedioxythiophene) (PEDOT) doped with bovine serum albumin-stabilized Au nanoclusters (AuNCs) was successfully synthesized through electrochemical polymerization in a solution containing EDOT monomer and AuNCs. The obtained PEDOT/AuNCs composite possessed a microstructure with AuNCs evenly distributed within the PEDOT film as dopants. The PEDOT/AuNCs modified electrode exhibited high electrocatalytic activity toward nitrite oxidation, and it was further developed into an amperometric sensor for nitrite. If operated at 0.80 V (vs. SCE), the linear range of the sensor was from 0.05 to 2600 μM, with a very low limit of detection of 17 nM (S/ N = 3). [ABSTRACT FROM AUTHOR]

Negatively charged carboxylated nanocrystalline cellulose (CNCC) and positively charged poly(diallyldimethyl ammonium chloride) (PDDA) were alternatingly assembled on the surface of a glassy carbon electrode to form a relatively uniform polyelectrolyte multilayer nanocomposite (CNCC/PDDA). It was then incorporated into a matrix of conducting poly(3,4-ethylenedioxythiophene) (PEDOT) electrodeposited on the surface of the electrode. The nanocomposites were prepared in various ratios of PEDOT and (CNCC/PDDA), and then characterized by transmission electron microscopy, scanning electron microscopy, electrochemical impedance spectroscopy, cyclic voltammetry, and differential pulse voltammetry. The PEDOT/(CNCC/PDDA) nanocomposite showed the lowest electrochemical impedance and best electrocatalytic activity towards the oxidation of nitrite. Based on these findings, an amperometric sensor was developed which, if operated at 0.80 V (vs. SCE), can detect nitrite in the 0.2 μM to 1.73 mM concentration range with a 57 nM detection limit. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The work describes the synthesis of a nanocomposite consisting of poly(3,4-ethylenedioxythiophene) (PEDOT) doped with gold nanoparticles (AuNPs) by electropolymerization of EDOT in a solution containing colloidal AuNPs. The nanocomposite possesses good conductivity and a 3D microporous network structure owing to the presence of AuNPs. These act as both conductive dopant and template for the growth of the microporous polymer. A glassy carbon electrode modified with the nanocomposite exhibits excellent electrocatalytic activity towards oxidation of nitrite. Best operated at a voltage of 0.8 V (vs. Ag/AgCl), it is capable of detecting nitrite in the 0.2 to 1400 μM concentration range, with a detection limit of 60 nM. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

An electrochemical dopamine sensor was developed by electrochemical modification of a carbon paste electrode with a biocomposite made from poly(3,4-ethylenedioxythiophene) (PEDOT) that was doped with double stranded or single stranded DNA. The resulting conducting biocomposite displays excellent electrocatalytic activity towards the oxidation of dopamine (DA) which is attributed to the presence of the DNA dopant. Under optimum conditions and at a working potential of 300 mV, the modified electrode is capable of detecting DA in the 0.25 to 66 μM concentration range. The detection limit is 74 nM. The sensor is not interfered by uric acid and ascorbic acid. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The ghrelin ( GHRL), ghrelin receptor ( GHSR), and insulin-like growth factor 1 receptor ( IGF1R) genes have crucial effects on body weight (BW), body weight gain (BWG), feed intake (FI), and feed conversion ratio (FCR) in many species. However, few studies on associations of GHRL, GHSR, and IGF1R with BWG, FI, and FCR have been reported in chickens. In this study, 16 SNPs in GHRL, GHSR, and IGF1R genes were genotyped by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The objective of this study was to examine the associations of GHRL, GHSR, and IGF1R genes polymorphisms with BW at 49 days (BW49) and 70 days (BW70) of age, BWG, FI, and FCR in the interval in two yellow meat-type populations with a total of 724 birds. The results showed that rs15675067 of GHRL was significantly associated with BW70, BWG, and FCR ( P < 0.05). For GHSR, rs16675844 had significant effects on FI and FCR ( P < 0.01), and that rs14678932 showed significant association with BWG and FI ( P < 0.05). Rs14011780 of IGF1R was strongly associated with BW49, BW70, and FCR ( P < 0.05). Furthermore, haplotypes based on three SNPs of rs14986828, rs15675067, and rs15675065 in GHRL were significantly associated with BW70 and FCR ( P < 0.05). Meanwhile, a three-SNP haplotype comprising rs14011783, rs14011780, and rs14011776 in IGF1R showed significant effects on BW49, BW70, and FCR ( P < 0.05). Therefore, it was concluded that the identified SNPs and analyzed haplotypes in this study might be useful for broiler breeding programs. [ABSTRACT FROM AUTHOR]

A sensitive and selective electrochemical sensor for the determination of nitrobenzene (NB) was developed based on a carbon paste electrode (CPE) modified with a nanocomposite prepared from the conducting polymer poly(3,4-ethylenedioxythiophene) and carbon nanotubes. The modified CPE exhibits good conductivity, a large surface area, and excellent catalytic activity towards the electrochemical reduction of NB. Under optimal conditions, the modified CPE is capable of detecting NB in the 0.25 to 43 μM concentration range and with a detection limit at 83 nM. Moreover, the sensor is highly stable and reusable, and free of interferences by other commonly present nitro compounds. It was used to determine NB in wastewater samples. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Flavin-containing monooxygenase 3 (FMO3) is an important monooxygenase for catalytic oxygenation of many harmful xenobiotics. Mutations in the FMO3 gene have been identified as causing trimethylaminuria in human and fishy off-flavor in cow milk and chicken eggs. In this study, the full-length cDNA sequence of Pekin duck FMO3 gene was cloned, sequenced, and characterized. The full-length cDNA sequence consisted of 1,846 bp and contained a 1,599 bp open-reading frame encoding 532 amino acids. Duck FMO3 gene shared a similar nine exon-eight intron structure with chicken and human. The duck FMO3 putative protein sequence showed high identity with that of chicken (82 %), and relative low identity with those of mammals (61-66 %). We also found that the duck FMO3 gene was dramatically expressed in liver, lung, and kidney compared to that in other tissues in the ducks, indicating the possible roles the FMO3 gene could play in the three tissues. By bidirectional sequencing, we also found one nonsense mutation, 5 nonsynonymous, and 21 synonymous mutations in the coding region of the FMO3 gene in 11 duck breeds and some of them were predicted to be potentially associated with the activities of FMO3 protein. [ABSTRACT FROM AUTHOR]

The electrochemical property of dinuclear copper(II) complex containing mixed ligands of N-hydroxyethylaminoethyl oxamido and 2,2′-bipyridine [Cu(bpy)(HAO)] was studied with cyclic voltammetry. Cu(bpy)(HAO) had irreversible oxidation peaks in 0.1 mol/L NaCl solution at the stearic acid-modified carbon paste electrode. Cyclic voltammetry and absorption spectra measurements were used to study the interaction between Cu(bpy)(HAO) and herring fish sperm DNA. All the experimental results showed that Cu(bpy)(HAO) interacted with DNA mainly through electrostatic affinity to make tiny difference between Cu(bpy)(HAO)-ssDNA and Cu(bpy)(HAO)-dsDNA. The binding ratio and the binding constant of DNA-Cu(bpy)(HAO) were calculated as 1:1 and 6.41 × 10, respectively. The redox peak current of Cu(bpy)(HAO) decreased markedly after its interaction with DNA. This was used to detect the concentration of DNA quantitatively. [ABSTRACT FROM AUTHOR]

In order to elucidate the domestication history of Peking ducks, 190 blood samples from six Chinese indigenous duck breeds were collected with186 individualsgenotyped by 15 microsatellite markers. Both the F ST and Nei’s standard genetic distances ( D s) from the microsatellite data indicated high genetic differentiation between Peking duck and other Chinese indigenous breeds. The haplotype network with mtDNA data showed that most of the Peking duck haplotypes were distinctly different from those of other domestic breeds. Although the H01 haplotype was shared by all domesticated duck breeds, Peking ducks displayed 12 specific domestic duck haplotypes, including four similar haplotypes H02, H04, H08 and H22, that formed a single haplogroup (A). Both H02 and H22 haplotypes were also shared by mallard and Peking ducks, indicating that Peking ducks originated from wild mallard ducks. [ABSTRACT FROM AUTHOR]

China is rich in chicken genetic resources, and many indigenous breeds can be found throughout the country. Due to poor productive ability, some of them are threatened by the commercial varieties from domestic and foreign breeding companies. In a large-scale investigation into the current status of Chinese poultry genetic resources, 78 indigenous chicken breeds were surveyed and their blood samples collected. The genomes of these chickens were screened using microsatellite analysis. A total of 2740 individuals were genotyped for 27 microsatellite markers on 13 chromosomes. The number of alleles of the 27 markers ranged from 6 to 51 per locus with a mean of 18.74. Heterozygosity ( H) values of the 78 chicken breeds were all more than 0.5. The average H value (0.622) and polymorphism information content (PIC, 0.573) of these breeds suggested that the Chinese indigenous chickens possessed more genetic diversity than that reported in many other countries. The fixation coefficients of subpopulations within the total population ( F ST) for the 27 loci varied from 0.065 (LEI0166) to 0.209 (MCW0078), with a mean of 0.106. For all detected microsatellite loci, only one (LEI0194) deviated from Hardy-Weinberg equilibrium (HWE) across all the populations. As genetic drift or non-random mating can occur in small populations, breeds kept on conservation farms such as Langshan chicken generally had lower H values, while those kept on large populations within conservation regions possessed higher polymorphisms. The high genetic diversity in Chinese indigenous breeds is in agreement with great phenotypic variation of these breeds. Using Nei’s genetic distance and the Neighbor-Joining method, the indigenous Chinese chickens were classified into six categories that were generally consistent with their geographic distributions. The molecular information of genetic diversity will play an important role in conservation, supervision, and utilization of the chicken resources. [ABSTRACT FROM AUTHOR]

An electrochemical sensor for paracetamol is described that consists of a glassy carbon electrode (GCE) that was modified with the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) doped with MnO2 nanoflowers. The hydrothermally synthesized MnO2 nanoflowers possess a large surface area and can be doped into PEDOT through electrochemical deposition to form a conducting polymer nanocomposite. The nanoflowers are shown to be uniformly distributed within the nanocomposite as revealed by elemental mapping analysis. The nanocomposite displays excellent catalytic activity toward the electrochemical oxidation of paracetamol. The modified GCE, best operated at a working potential of around 0.37 V (vs. SCE) has a linear response in 0.06 to 435 μM paracetamol concentration range and a very low limit of detection (31 nM at a signal-to-noise ratio of 3). The sensor exhibits excellent reproducibility and stability, and satisfying accuracy for paracetamol detection in pharmaceutical samples. [ABSTRACT FROM AUTHOR]

The authors describe an electrochemical aptasensor for thrombin that is based on the use of a glassy carbon electrode (GCE) modified with polydopamine that is loaded with silver nanoparticles (PDA/AgNPs). The use of AgNPs improves the conductivity of the film and increases the surface area of the GCE. PDA was deposited on the GCE via self-polymerization, and the thrombin binding aptamer was grafted onto the PDA-modified GCE by a single step reaction. Residual electrode surface was blocked with 6-mercapto-1-hexanol. On exposure to thrombin, the electrochemical impedance of the modified electrode increases gradually. Response is linear in the 0.1 pM to 5.0 nM thrombin concentration range, and the limit of detection is as low as 36 fM. The method is selective and capable of detecting thrombin in diluted human serum. In our perception, such a GCE modified with AgNP in a PDA matrix may be applied to many other analytes for which appropriate aptamers are available.Schematic of an electrochemical aptasensor for sensitive and selective thrombin detection based on the use of a self-polymerized polydopamine film loaded with silver nanoparticles. [ABSTRACT FROM AUTHOR]