bluuebunny/crossref_metadata_2025 huggingface dataset:
Rapid synthesis of hybrids and hollow PdO nanostructures by controlled in situ dissolution of a ZnO nanorod template: insights into the formation mechanism and thermal stability
Authors: Kundu Subhajit , Ravishankar N.
Published: December 2015

Hollow to hybrid PdO nanostructures by controlling the dissolution of ZnO nanorod template.
Synergistic dual-pH responsive copolymer micelles for pH-dependent drug release
Authors: Deng Hongzhang , Zhao Xuefei , Liu Jinjian , Zhang Jianhua , Deng Liandong , Liu Jianfeng , Dong Anjie
Published: December 2015

Doxorubicin encapsulated into micelles of dual-pH responsive copolymer show fast acidic-degradation rate but high stability under physiological conditions.
Palladium-catalyzed enolate arylation as a key C–C bond-forming reaction for the synthesis of isoquinolines
Authors: Pilgrim Ben S. , Gatland Alice E. , Esteves Carlos H. A. , McTernan Charlie T. , Jones Geraint R. , Tatton Matthew R. , Procopiou Panayiotis A. , Donohoe Timothy J.
Published: December 2015

The four-component, one-pot synthesis of isoquinolines utilizing the palladium-catalyzed α-arylation of ketone, ester and nitrile enolates.
In Vitro selectivity of an acyclic cucurbit[n]uril molecular container towards neuromuscular blocking agents relative to commonly used drugs
Authors: Ganapati Shweta , Zavalij Peter Y. , Eikermann Matthias , Isaacs Lyle
Published: December 2015

We measure the binding affinity of Calabadion 2 toward 27 drugs to assess its selectivity toward rocuronium, vecuronium, and cisatracurium.
Mechanism, chemoselectivity and enantioselectivity for the rhodium-catalyzed desymmetric synthesis of hydrobenzofurans: a theoretical study
Authors: Yu Zhaoyuan , Qi Xiaotian , Li Yingzi , Liu Song , Lan Yu
Published: December 2015

A theoretical study of Rhodium-catalyzed desymmetrization of cyclohexadienones.
Rapid access to bicyclic δ-lactones via carbene-catalyzed activation and cascade reaction of unsaturated carboxylic esters
Authors: Fu Zhenqian , Wu Xingxing , Chi Yonggui Robin
Published: December 2015

The carbene-catalyzed activation of α,β-unsaturated ester initiates a well-controlled cascade process for access to iridoid-type multi-cyclic lactones with high stereo-selectivities.
Self-buffering and biocompatible ionic liquid based biological media for enzymatic research
Authors: Gupta Bhupender S. , Taha Mohamed , Lee Ming-Jer
Published: December 2015

New self-buffering Good's buffer ionic liquids (GBILs) were synthesized for biological research.
Evaluation of poly(pyrrole-2-carboxylic acid) particles synthesized by enzymatic catalysis
Authors: Kausaite-Minkstimiene A. , Ramanaviciene A. , Simanaityte R. , Gabrielaitis D. , Glumbokaite L. , Ramanavicius A.
Published: December 2015

In this study an environmentally friendly synthesis of poly(pyrrole-2-carboxylic acid) (PCPy) particles dispersed in water–ethanol medium using enzymatic catalysis is proposed.
Conversion from self-assembled block copolymer nanodomains to carbon nanostructures with well-defined morphology
Authors: Sun Ya-Sen , Huang Wei-Hua , Liou Jiun-You , Lu Yen-Hsing , Shih Kuo-Chih , Lin Chien-Fu , Cheng Shao-Liang
Published: December 2015

A SiO2 capping layer appears to have two advantages – increased areal yields and an improved morphological fidelity.
A mechanistic approach for superoxide radicals and singlet oxygen mediated enhanced photocatalytic dye degradation by selenium doped ZnS nanoparticles
Authors: Talukdar Soumita , Dutta Raj Kumar
Published: December 2015

Superoxide and singlet oxygen mediated photocatalytic dye degradation by Se-doped ZnS NPs.
Fabrication of a dendrimer-modified boronate affinity material for online selective enrichment of cis-diol-containing compounds and its application in determination of nucleosides in urine
Authors: Gao Li , Du Jin , Wang Chaozhan , Wei Yinmao
Published: December 2015

A high binding capacity dendrimer-modified boronate affinity material (SiO2@dBA) was synthesized and coupled with large-volume injection/online column-switching solid phase extraction to facilitate the determination process of cis-diols.
The ligands of neutrophil gelatinase-associated lipocalin
Authors: Bao Guan-Hu , Ho Chi-Tang , Barasch Jonathan
Published: December 2015

Ligands of Ngal: hydrophobic, bacterial siderophores together with their modified structures, mammalian siderophores and consequently related functions were summarized.
Effect of the matrix modification technique (MMT) on the composition, microstructure, morphology, interfacial interaction and mechanical properties of polypropylene reactor alloys
Authors: Mousavi Seyed Omidreza , Jahani Yousef , Arabi Hassan
Published: December 2015

In this paper, a new approach was applied to improve phase compatibility of isotactic polypropylene (iPP) reactor alloys through a matrix modification technique (MMT).
Hydrogen titanate constructed by ultrafine nanobelts as advanced anode materials with high-rate and ultra-long life for lithium-ion batteries
Authors: Tian Qinghua , Tian Yang , Zhang Zhengxi , Yang Li , Hirano Shin-ichi
Published: December 2015

The electrochemical performance of hydrogen titanate has been successfully and significantly improved by novel morphology engineering and heat treatment strategies.
Thermal-based regulation on biomineralization and biological properties of bioglass nanoparticles decorated PAN-based carbon nanofibers
Authors: Cheng Dan , Ren Zhiwei , Guo Lijuan , Zhang Cuihua , Jia Xiaolong , Cai Qing , Yang Xiaoping
Published: December 2015

The mechanism and model for biomineralization behavior and cell culture of CNF/BG sintered at various temperatures.
Dissolution and oriented aggregation: transformation from lepidorocite to goethite by the catalysis of aqueous Fe(ii)
Authors: Yan Wenjing , Liu Hui , Chen Rufen , Xie Juan , Wei Yu
Published: December 2015

At a low temperature, lepidocrocite-to-goethite transformation occurred in the presence of Fe(ii) ions, whereas lepidocrocite was stable in the absence of Fe(ii) ions.
Calculation of protein–ligand binding affinities based on a fragment quantum mechanical method
Authors: Liu Jinfeng , Wang Xianwei , Zhang John Z. H. , He Xiao
Published: December 2015

An efficient fragment-based quantum mechanical method has been successfully applied for reliable prediction of protein–ligand binding affinities.
In situ preparation and characterization of a conductive and magnetic nanocomposite of polypyrrole and copper hydroxychloride
Authors: Kasisomayajula Subramanyam , Jadhav Niteen , Gelling Victoria Johnston
Published: December 2015

A nanocomposite of polypyrrole and copper hydroxychloride with combined conductive and ferrimagnetic properties was synthesized in a single-step in situ chemical oxidation process.
Todorokite-type manganese oxide nanowires as an intercalation cathode for Li-ion and Na-ion batteries
Authors: Byles B. W. , West P. , Cullen D. A. , More K. L. , Pomerantseva E.
Published: December 2015

Extended hydrothermal treatment at an elevated temperature of 220 °C allowed high yield synthesis of manganese oxide nanowires with a todorokite crystal structure suitable for reversible intercalation of Li+ and Na+ ions.
Synthesis of novel monolithic activated carbons from phenol–urea–formaldehyde resin
Authors: Zhao W. , Gao H. , Fan M.
Published: December 2015

Phenol–urea–formaldehyde (PUF) organic foams have been firstly synthesized from phenol–urea–formaldehyde resin under alkaline conditions, which can be used as precursor to produce cellular activated carbon foams.
Structure and thermal properties of phosphorus-containing polyol synthesized from cardanol
Authors: Bo Caiying , Hu Lihong , Jia Puyou , Liang Bingchuang , Zhou Jing , Zhou Yonghong
Published: December 2015

P-Containing cardanol polyol (PCP), a novel cardanol derivative, was synthesized.
Simple and convenient G-quadruplex-based fluorescence assay of micrococcal nuclease activity
Authors: He Yue , Jiao Bining
Published: December 2015

An ultrasensitive and straightforward fluorescence sensing platform for MNase activity has been developed based on NMM/G-quadruplexes.
Atomistic level molecular dynamics simulation on the solubilization mechanism of aromatic molecules in anionic micelles
Authors: Mondal Sourav , Ghosh Sudipto , De Sirshendu
Published: December 2015

Benzene is solubilized in the palisade layer, toluene in the core (or central region), phenol at the surface and pyridine in micelle–water interface. During micellar enhanced ultrafiltration, phenol will have least rejection while benzene is maximum.
Fabrication of highly fluorescent CdSe quantum dots via solvent-free microfluidic spinning microreactors
Authors: Liu Wei , Zhang Yan , Wang Cai-Feng , Chen Su
Published: December 2015

The available method for in situ fabrication of highly fluorescent hybrid materials prepared via microfluidic spinning technology (MST) have been demonstrated.
Effect of multifunctional samarium lysine dithiocarbamate on curing properties, static and dynamic mechanical properties of SBR/silica composites
Authors: Zou Yongkun , He Jingwei , Tang Zhenghai , Zhu Lixin , Luo Yuanfang , Liu Fang
Published: December 2015

In this work, a novel multifunctional rubber agent named as samarium lysine dithiocarbamate (Sm-LDC) was synthesized by a nucleophilic addition reaction and coordination reaction.
One step synthesis of highly functionalized thiazolo[3,2-b][1,2,4]triazole, triazolo[1,5-a]pyrimidine and triazolo[3,4-b][1,3,4]thiadiazine
Authors: Shah Tariq A. , Ahmad Zubair , Mir Niyaz A. , Muneer M. , Rath Nigam P. , Ahmad Musheer
Published: December 2015

An efficient and straight forward methodology for the preparation of novel functionalized thiazolo[3,2-b]triazole, triazolo[1,5-a]pyrimidine and triazolo[3,4-b][1,3,4]thiadiazine.
The recent developments and applications of the traceless-Staudinger reaction in chemical biology study
Authors: Wang Zhi-Peng A. , Tian Chang-Lin , Zheng Ji-Shen
Published: December 2015

Bioorthogonal reactions are one of the most important topics in chemical biology. Traceless-Staudinger reaction/ligation has been investigated and widely applied in life science. Herein, the current developments, mechanism studies, and biological applications are summarized.
Renewable pine cone biomass derived carbon materials for supercapacitor application
Authors: Bello Abdulhakeem , Manyala Ncholu , Barzegar Farshad , Khaleed Abubakar A. , Momodu Damilola Y. , Dangbegnon Julien K.
Published: December 2015

We report on the transformation of pine cone biomass into porous carbonviaKOH activation and carbonization at 800 °C as electrode materials for supercapacitors.
Large-scale growth of sharp gold nano-cones for single-molecule SERS detection
Authors: Zhang Ling , Liu Hongwen , Chen Luyang , Guan Pengfei , Chen Bin , Fujita Takeshi , Yamaguchi Yoshinori , Iwasaki Hiroshi , Xue Qi-Kun , Chen Mingwei
Published: December 2015

Quasi-periodic Au nano-cone arrays uniformly sprout on centimeter-sized free-standing nanoporous gold (NPG) films via epitaxial plating, and the nano-cones@NPG serve as a high-performance SERS substrate for single molecule detection.
Enhanced electrical properties in ferroelectric thin films on conductive Au–LaNiO3 nanocomposite electrodes via modulation of Schottky potential barrier
Authors: Wang Hailing , Bai Yu , Ning Xingkun , Wang Zhanjie
Published: December 2015

In this work, ferroelectric Pb(Zr,Ti)O3 (PZT) thin films deposited on Au–LNO nanocomposite bottom electrode exhibited enhanced ferroelectric properties via modulation of Schottky potential barrier at the ferroelectric film/electrode interface.
Structural and electronic properties of alkali metal peroxides at high pressures
Authors: Deng Naihang , Wang Wenyong , Yang Guochun , Qiu Yongqing
Published: December 2015

Different phase transition mechanisms and structures have been observed for alkali metal peroxides (Li2O2, Na2O2, K2O2, Rb2O2) under pressure. Phase transition pressures of the studied compounds closely related to the alkali metal electronegativity.
Phthalate tethered strategy: carbohydrate nitrile oxide cycloaddition to 12–15 member chiral macrocycles with alkenyl chain length controlled orientation of bridged isoxazolines
Authors: Majumdar Swapan , Hossain Jewel , Natarajan Ramalingam , Banerjee Ashish K. , Maiti Dilip K.
Published: December 2015

The highly selective synthesis of phthalate templated bridged sugar-based isoxazoline macrocyclic lactones is demonstrated through INOC with alkene.
pH-Controlled multiple-drug delivery by a novel antibacterial nanocomposite for combination therapy
Authors: Bazmi zeynabad Fatemeh , Salehi Roya , Alizadeh Effat , Kafil Hossein Samadi , Hassanzadeh Azad Mohammad , Mahkam Mehrdad
Published: December 2015

The modified cationic silica based stimuli responsive polymer–clay nanocomposite with pH responsive release manner could improve the targeting performance.
Ligand-free N-arylation of heterocycles using metal–organic framework [Cu(INA)2] as an efficient heterogeneous catalyst
Authors: Truong Thanh , Nguyen Chi V. , Truong Ngoc T. , Phan Nam T. S.
Published: December 2015

A metal–organic framework [Cu(INA)2] was synthesized and used as a heterogeneous catalyst for arylation of a wide range of N–H heterocycles and aryl halides under ligand-free conditions.
Photocytotoxic luminescent lanthanide complexes of DTPA–bisamide using quinoline as photosensitizer
Authors: Singh Khushbu , Banerjee Samya , Patra Ashis K.
Published: December 2015

Luminescent lanthanide(iii) complexes of DTPA–bisamide quinoline as photosensitizer were studied for their structures, luminescent properties, binding with DNA and protein, photo-induced DNA cleavage, photocytotoxicity and cellular uptake studies.
Metal-free catalytic cascade to chromones: direct coupling of salicylaldehydes and activated alkynes triggered by aryloxyl radicals
Authors: Wang Ping , Li Zhongfeng , Cao Shengli , Rao Honghua
Published: December 2015

The first intermolecular addition reaction of aryloxyl radicals to CC bonds was disclosed, which can afford biologically important chromonsviaa PhNMe3I-catalyzed direct coupling of salicylaldehydes and activated internal alkynes in only one step.
Flipped classroom modules for large enrollment general chemistry courses: a low barrier approach to increase active learning and improve student grades
Authors: Eichler Jack F. , Peeples Junelyn
Published: December 2015

In the face of mounting evidence revealing active learning approaches result in improved student learning outcomes compared to traditional passive lecturing, there is a growing need to change the way instructors teach large introductory science courses. However, a large proportion of STEM faculty continues to use traditional instructor-centered lectures in their classrooms. In an effort to create a low barrier approach for the implementation of active learning pedagogies in introductory science courses, flipped classroom modules for large enrollment general chemistry course sequence have been created. Herein is described how student response systems (clickers) and problem-based case studies have been used to increase student engagement, and how flipped classroom modules have integrated these case studies as collaborative group problem solving activities in 250–500 seat lecture halls. Preliminary evaluation efforts found the flipped classroom modules provided convenient access to learning materials that increased the use of active learning in lecture and resulted in a significant improvement in the course grade point average (GPA) compared to a non-flipped class. These results suggest this approach to implementing a flipped classroom can act as a model for integrating active learning into large enrollment introductory chemistry courses that yields successful outcomes.
An effective strategy for recapitulating N-terminal heptad repeat trimers in enveloped virus surface glycoproteins for therapeutic applications
Authors: Lai Wenqing , Wang Chao , Yu Fei , Lu Lu , Wang Qian , Jiang Xifeng , Xu Xiaoyu , Zhang Tianhong , Wu Shengming , Zheng Xi , Zhang Zhenqing , Dong Fangting , Jiang Shibo , Liu Keliang
Published: December 2015

We report an efficient strategy to recapitulate NHR α-helical trimers in the HIV-1 membrane fusion protein as promising antiviral therapeutics.
Roles of structural plasticity in chaperone HdeA activity are revealed by 19F NMR
Authors: Zhai Zining , Wu Qiong , Zheng Wenwen , Liu Maili , Pielak Gary J. , Li Conggang
Published: December 2015

Multiple conformations of acid chaperone HdeA and their roles in activity.
High transparency in the structural color resin films through quasi-amorphous arrays of colloidal silica nanospheres
Authors: Lai Chun-Feng , Wang Yu-Chi , Hsu Hsiang-Chih
Published: December 2015

Novel quasi-amorphous structural color resin films are highly transparent, and have a uniform shining reflection color and physical rigidity, and so have enormous potential.
An organic–metal–inorganic three-component nanojunction array: design, construction and its reversible diode-like resistive electrical switching behavior
Authors: Wang Jing , Xu Weiqing , Liu Xiangyuan , Bai Fou , Zhou Xianghua , Xu Shuping
Published: December 2015

AgTCNQF4–AgNPs–TiO2 as an organic–metal–inorganic hetero-nanojunction shows a switchable diode effect, reversible electrical switching and memory behavior.
Highly stretchable and sensitive piezoresistive carbon nanotube/elastomeric triisocyanate-crosslinked polytetrahydrofuran nanocomposites
Authors: Wang Yunming , Mi Hongyi , Zheng Qifeng , Zhang Huilong , Ma Zhenqiang , Gong Shaoqin
Published: December 2015

A family of CNT/ETC-PTHF nanocomposites exhibiting high stretchability and high sensitivity to mechanical stimuli was developed. The electrical conductivity change of 15 wt% CNT/ETC-PTHF nanocomposites decreased by 7.3% and 1291 times under 1% and 500% tensile strain, respectively.
Mechanisms of epigenetic remodelling during preimplantation development
Authors: Ross Pablo Juan , Canovas Sebastian
Published: December 2015

Epigenetics involves mechanisms independent of modifications in the DNA sequence that result in changes in gene expression and are maintained through cell divisions. Because all cells in the organism contain the same genetic blueprint, epigenetics allows for cells to assume different phenotypes and maintain them upon cell replication. As such, during the life cycle, there are moments in which the epigenetic information needs to be reset for the initiation of a new organism. In mammals, the resetting of epigenetic marks occurs at two different moments, which both happen to be during gestation, and include primordial germ cells (PGCs) and early preimplantation embryos. Because epigenetic information is reversible and sensitive to environmental changes, it is probably no coincidence that both these extensive periods of epigenetic remodelling happen in the female reproductive tract, under a finely controlled maternal environment. It is becoming evident that perturbations during the extensive epigenetic remodelling in PGCs and embryos can lead to permanent and inheritable changes to the epigenome that can result in long-term changes to the offspring derived from them, as indicated by the Developmental Origins of Health and Disease (DOHaD) hypothesis and recent demonstration of inter- and trans-generational epigenetic alterations. In this context, an understanding of the mechanisms of epigenetic remodelling during early embryo development is important to assess the potential for gametic epigenetic mutations to contribute to the offspring and for new epimutations to be established during embryo manipulations that could affect a large number of cells in the offspring. It is of particular interest to understand whether and how epigenetic information can be passed on from the gametes to the embryo or offspring, and whether abnormalities in this process could lead to transgenerationally inheritable phenotypes. The aim of this review is to highlight recent progress made in understanding the nature and mechanisms of epigenetic remodelling that ensue after fertilisation.
Pregnancy losses in cattle: potential for improvement
Authors: Diskin M. G. , Waters S. M. , Parr M. H. , Kenny D. A.
Published: December 2015

For heifers, beef and moderate-yielding dairy cows, it appears that the fertilisation rate generally lies between 90% and 100%. For high-producing dairy cows, there is a less substantive body of literature, but it would appear that the fertilisation rate is somewhat lower and possibly more variable. In cattle, the major component of embryo loss occurs in the first 16 days following breeding (Day 0), with emerging evidence of greater losses before Day 8 in high-producing dairy cows. In cattle, late embryo mortality causes serious economic losses because it is often recognised too late to rebreed females. Systemic concentrations of progesterone during both the cycle preceding and following insemination affect embryo survival, with evidence of either excessive or insufficient concentrations being negatively associated with survival rate. The application of direct progesterone supplementation or treatments to increase endogenous output of progesterone to increase embryo survival cannot be recommended at this time. Energy balance and dry matter intake during the first 4 weeks after calving are critically important in determining pregnancies per AI when cows are inseminated at 70–100 days after calving. Level of concentrate supplementation of cows at pasture during the breeding period has minimal effects on conception rates, although sudden reductions in dietary intake should be avoided. For all systems of milk production, more balanced breeding strategies with greater emphasis on fertility and feed intake and/or energy must be developed. There is genetic variability within the Holstein breed for fertility traits, which can be exploited. Genomic technology will not only provide scientists with an improved understanding of the underlying biological processes involved in fertilisation and the establishment of pregnancy, but also, in the future, could identify genes responsible for improved embryo survival. Such information could be incorporated into breeding objectives in order to increase the rate of genetic progress for embryo survival. In addition, there is a range of easily adoptable management factors, under producer control, that can either directly increase embryo survival or ameliorate the consequences of low embryo survival rates. The correction of minor deficits in several areas can have a substantial cumulative positive effect on herd reproductive performance.
101 TOWARDS OPTIMAL IN VITRO CULTURE CONDITIONS FOR PIG-MONKEY AGGREGATION CHIMERAS
Authors: Burchardt B. , Lucas-Hahn A. , Hassel P. , Ziegler M. , Neuhaus G. , Wunderlich S. , Petkov S. , Martin U. , Niemann H.
Published: December 2015

Induced pluripotent stem cells (iPSCs) are promising for developing novel cell-based medical treatments. One potential use of iPSCs is for xenotransplantation via production of chimeric organisms. The generation of organs originated from the iPSCs of one individual in a foreign organism could allow the production of immune compatible organ transplants. One of the major problems down this road is to define the different nutrient needs of chimeric embryos (i.e. iPSCs and the host embryos). Here, we evaluated different media for supporting development of chimeric embryos consisting of parthenogenetic porcine embryos and iPS cells, either from pig or nonhuman primate, to identify the optimal medium conditions for pig-monkey aggregation chimeras. First, we cultured 3-day-old porcine parthenogenetic embryos in porcine zygote medium (PZM), iPSC-medium, and mixtures of the two media to identify the most suitable culture conditions. Three-day-old parthenogenetic embryos developed poorly in pure iPSC-medium (6.3% blastocyst rate), but grew in a mixture of PZM and iPSC medium. The best results were achieved with PZM and PZM with 10% or 25% iPSC medium (38.8% and 30% blastocyst rates, respectively). Next, we checked aggregation results of chimeric embryos produced with two different iPSC lines in the respective media (PZM, PZM+10% iPSC medium, PZM+25% iPSC medium). The porcine iPSC line (piPSC) and cynomolgus monkey iPSC line (ciPSC) carry fluorescent markers (piPSC: GFP, ciPSC: venus), thus facilitating detection of integration into the host embryos. After aggregation of iPS cells between two Day-3 parthenogenetic embryos (sandwich technique), blastocyst rates at Day 6 were determined (see Table 1). While culture in PZM allowed for the highest blastocyst rate (>40%), the iPS cell participation was very low (0–11.1%). Cultivation in PZM+25% iPS medium was compatible with a high rate of embryo-iPSC chimeras (50–100%), but with a low blastocyst rate (7.7–16.7%). Possibly, the iPS cells proliferate more rapidly than blastomeres and the embryo is overgrown. The best results were obtained in medium mixture PZM+10% iPSC medium (25–40% blastocyst rate with 66.7–100% iPS cell participation). These results show that supplementation of the basic culture medium with 10% iPSC medium yields high blastocyst rates for chimeric embryos, and also ensures much higher iPS cell participation. This improves the use of 3-day-old embryos in aggregation chimeras.

Table 1.Development of parthenogenetic porcine embryo aggregates with porcine (p) or cynomolgus monkey (c) iPS cells
107 FACTORS THAT INFLUENCE FERTILITY IN AN IVF EMBRYO TRANSFER PROGRAM IN DAIRY HEIFERS
Authors: Carrenho-Sala L. C. , Sala R. V. , Fosado M. , Pereira D. C. , Garcia S. , Lopez A. , Moreno J. F. , Garcia-Guerra A. , Wiltbank M. C.
Published: December 2015

A retrospective study was performed to evaluate factors that influence pregnancy per embryo transfer (P/ET) in an IVF-embryo transfer program. A total of 5026 fresh in vitro-produced embryos were transferred during 2014 and evaluated for effects of embryo quality, embryo stage, size of corpus luteum (CL; 18–19.9 mm or ≥20 mm), interval from GnRH to embryo transfer, number of previous embryo transfer (0, 1, 2, 3, ≥4); and interaction of embryo stage and interval from GnRH to embryo transfer. One group (n = 850) had detection of oestrus after prostaglandin F2α application but most heifers (n = 4176) received fixed timed embryo transfer after a 5-day CIDR-Synch protocol: Day –8 CIDR inserted; Day –3 CIDR removed and prostaglandin F2α; Day –2 prostaglandin F2α; Day 0 GnRH. Ultrasound was performed on Day 6 after GnRH or oestrus to measure CL size and on Day 32 and 60 to determine pregnancy. Data for P/ET were analysed by logistic regression (LOGISTIC procedure, SAS 9.4). Embryo quality influenced P/ET at Day 32 [Grade 1 48.4% (1273/2631) v. Grade 2 37.6% (900/2395); P < 0.01] and at Day 60 [Grade 1 38.9% (1023/2631) v. Grade 2 29.0% (694/2395); P < 0.01], and altered pregnancy loss [Grade 1 19.6% (250/1273) v. Grade 2 22.9% (206/900); P = 0.03]. Stage of the embryo also had an effect on P/ET at Day 32 [Stage 6 35.5%a (582/1641), Stage 7 46.3%b (1431/3092), and Stage 8 54.6%c (160/293); P < 0.01] and at Day 60 [Stage 6 28.2%a (462/1641), Stage 7 36.6%b (1131/3092), and Stage 8 41.6%b (122/293); P < 0.01], but did not affect pregnancy loss (P = 0.22). Interestingly, interval from GnRH (or oestrus) until embryo transfer did not affect P/ET at Day 32 (P = 0.10), 60 (P = 0.23), or pregnancy loss (P = 0.3), nor was there an interaction between interval and embryo stage at Day 32 (P = 0.77), 60 (P = 0.96) or pregnancy loss (P = 0.55). As shown in Table 1, embryo stage 6 was always the lowest and stage 8 always the greatest P/ET regardless of interval from GnRH to embryo transfer. Size of CL also did not affect P/ET at Day 32 (P = 0.09), 60 (P = 0.21), or pregnancy loss (P = 0.90). Number of previous embryo transfer also did not alter P/ET at Day 32 [0 = 43.3% (886/2046), 1 = 44.1% (639/1450), 2 = 43.4% (444/1024), 3 = 42.6% (146/343), and ≥4 = 35.6% (58/163); P = 0.33] or 60 (P = 0.51) or pregnancy loss (P = 0.12). In conclusion, embryo stage and quality are the major factors that impacted P/ET in this study, with surprisingly little effect of interval from GnRH to embryo transfer, size of the CL, and number of previous embryo transfer. Thus, recipient programs for IVF-embryo transfer can be designed with substantial flexibility.

Table 1.Effect of embryo stage and recipient synchrony on pregnancies per embryo transfer on Day 32 in recipient dairy heifers
111 RISK OF CHLAMYDIA ABORTUS TRANSMISSION VIA EMBRYO TRANSFER USING IN VITRO EARLY BOVINE EMBRYOS
Authors: Fieni F. , Oseikria M. , Laroucau K. , Vorimore F. , Tainturier D. , Destrumelle S. , Pellerin J. L.
Published: December 2015

Chlamydia abortus (C. abortus) in cattle has been reported sporadically throughout the world and is implicated in respiratory, ocular, and reproductive disease as abortion, infertility, chronic mastitis, vaginal discharge, and endometritis. In addition, C. abortus presents a zoonotic risk exposure of pregnant women to infected animal and can lead to severe septicaemia in the mother, resulting in spontaneous abortion or stillbirth of the fetus. To investigate the risk of C. abortus transmission via bovine embryo transfer, our study aims to determine whether the embryonic ZP of in vitro-produced embryos protects early embryo cells against C. abortus infection and whether the bacteria adhere to or infect the cells of early bovine embryos (ZP-free) after in vitro infection. We also evaluated the efficacy of the washing procedure recommended by the IETS to decontaminate bovine embryos exposed to C. abortus in vitro. Ninety (8 to 16 cells) bovine embryos, produced in vitro, were randomly divided into 10 batches. Eight batches (4 ZP-intact and 4 ZP-free) of 10 embryos were incubated in a medium containing 4.8 × 107 Chlamydia/mL of AB7 strain (ANSES, Maisons-Alfort, France). After incubation for 18 h at 37°C in an atmosphere of 5% CO2, the embryos were washed in batches in 10 successive baths of a PBS and 5% FCS solution without trypsin nor antibiotics in accordance with IETS guidelines. In parallel, 2 batches of 5 embryos (1 ZP-intact and 1 ZP-free) were subjected to similar procedures but without exposure to C. abortus as a control group. The 10 washing fluids from each batch were collected and centrifuged for 1 h at 13 000 × g. The embryos and wash pellets were tested using RT-PCR. Chlamydia abortus DNA was found in all ZP-intact and ZP-free infected embryos after 10 successive washes. It was also detected in the tenth wash fluid for 1 batch (1/4) of ZP-intact infected embryos and in 3 batches (3/4) of ZP-free infected embryos. In contrast, none of the embryos or their washing fluids in the control batches was DNA positive. These results demonstrate that C. abortus adheres to or penetrates the ZP as well as the early embryonic cells of in vitro-produced bovine embryos after in vitro infection, and that the standard washing protocol recommended by the IETS failed to remove it. The persistence of these bacteria after washing makes the embryo a potential means of transmission of the bacterium during embryo transfer from infected donor cows to healthy recipients or their offspring. Nevertheless, the finding of C. abortus DNA by RT-PCR did not imply that the bacteria found is still infective. Further studies are required to investigate whether enzymatic or antibiotic treatment of bovine embryos infected by C. abortus would eliminate the bacteria from the ZP.
120 IMPACT OF SEASON ON SEMINAL CHARACTERISTICS AND SPERM CRYOPRESERVATION IN THE TUFTED DEER (ELAPHODUS CEPHALOPHUS)
Authors: Panyaboriban S. , Songsasen N. , Singh R. P. , Padilla L. , Brown J. , Reed D. , Techakumphu M. , Pukazhenthi B.
Published: December 2015

The Tufted deer (Elaphodus cephalophus), a small deer species native to China, is listed as near threatened on the IUCN Red List and >70 animals are managed in North American zoos as a hedge against extinction. In this study, we 1) characterized the seminal traits, 2) assessed the impact of season on ejaculate traits and testosterone level, and 3) examined sperm sensitivity to cryopreservation. Semen (24 ejaculates) were obtained from five males (1–2 ejaculates/male per season) by electro-ejaculation and evaluated for volume, osmolality, pH as well as sperm concentration, motility (%M), forward progression (FP, scale = 0–5) and acrosomal integrity (%AI). Ejaculates were divided into two aliquots and cryopreserved (4% vol/vol glycerol final concentration; 50–200 × 106 sperm mL–1) over liquid nitrogen vapor using Beltsville extender (BF5F; Howard et al. 1986) or Triladyl® (TRIL; Minitüb GmbH, Germany) extender. Sperm motility and %AI were assessed immediately (subjective) upon thawing and following swim-up processing (SU; 30 min) using computer-assisted semen analysis after 1, 2, 3, and 4 h of incubation (37°C). Fecal samples were collected 3–5 times weekly for 2 years and analyzed for testosterone (T) metabolites using enzyme immunoassay as a function of season (autumn, September–November; winter, December–February; spring, March–May; and summer, June–August). Data were analyzed using Proc GLM or ANOVA with Tukey multiple mean comparison. Significance was set at P < 0.05. Male reproductive and semen traits peaked in autumn (volume, 2.0 mL; concentration, 207.6 × 106 mL–1; pH, 7.6; osmolality, 310.8 mOsm; %M, 76%; FP, 3.5; and %AI, 82.3). Mean testicular length and neck girth in autumn were 4.9 and 43.2 cm, respectively. Mean T concentration (~1.23 µg g–1 of dry feces) was higher (P < 0.05) in summer compared with winter (1.07 µg g–1 of dry feces) or spring (1.06 µg g–1 of dry feces). Sperm motility and %AI were lower (P < 0.05) immediately after thawing (BF5F, 34.6 and 34.7%, respectively; and TRIL, 23.1 and 29.1%, respectively) compared with fresh semen (76.9 and 74.6%, respectively). Motility characteristics immediately after SU (computer-assisted semen analysis) were higher (P < 0.05) in BF5F compared with TRIL: %M (56.4 v. 44.9%), progressive motility (42.5 v. 21.9%), %AI (41.2 v. 31.3%), straight-line velocity (68.0 v. 53.2 µm s–1), straightness (85.1 v. 75.1%), and linearity (54.3 v. 45.0%). At the end of 4 h of incubation, sperm %M and FP declined (P > 0.05) in both BF5F and TRIL (47 and 30%, respectively) but the %AI was higher (P < 0.05) in BF5F (32%) than TRIL (21%). Results indicate that tufted deer ejaculates exhibit seasonal variations in reproductive traits and cryopreservation in BF5F better preserves sperm motility and acrosomal membrane integrity compared with TRIL.
133 ANTRAL FOLLICLE COUNT, VULVA WIDTH, AND FERTILITY TRAITS IN BOS TAURUS INDICUS CATTLE (TABAPUÃ)
Authors: Maculan R. , Rosa R. G. , Bonfim R. R. , Vasconcelos G. L. , Pinto T. L. C. , Moreira G. M. , Viafara J. A. S. , Gonçalves T. M. , Souza J. C.
Published: December 2015

The intense selection of characteristics related to animal production may affect negatively the reproductive efficiency of beef cattle. Thus, the search for characteristics that indicate fertility is readily justifiable in the selection of bovine females. The aim was to evaluate possible associations between the antral follicle counts (AFC), external genitalia measurements, and reproduction efficiency in Tabapuã (a Zebu breed from Brazil) females. The AFC was evaluated in Nulliparous heifers (n = 162) and cows (n = 429) by directly counting all follicles ≥3 mm in diameter with ultrasound. From the frequency distribution of the AFC, animals were divided into groups of high (>50 follicles), average (28–50 follicles), and low (<28 follicles), according to Burns et al. (2005). The vulva width was determined by measuring the distance between the lateral borders of the vulva with a digital caliper placed at a 90-degree angle from the half point of the rima vulvae. Two official reproductive efficiency indexes, adopted by the Brazilian Zebu Breeders Association (ABCZ), were used: age at first calving and calving interval. All statistical analyses were performed using SAS (SAS Institute Inc., Cary, NC, USA). An initial complete model was submitted to logistic regression and all body measurements, such as weight, rump height, and width at pins and hooks, were later excluded because they had no relationships with AFC. The AFC class and parity effects of vulva width were submitted to the PROCGENMOD procedure and the reproductive efficiency indexes were regressed onto age, vulva width and the AFC using the PROCREG procedure. Vulva width was greater (P = 0.05) in the high-AFC class cows (8.81 ± 0.12 cm) in comparison to those of the low (8.38 ± 0.13 cm) and average (8.42 ± 0.11 cm) classes, and was not influenced (P = 0.08) by parity (8.37 ± 0.11 and 8.77 ± 0.14 cm for heifers and cows, respectively). Vulva width was larger in cows with lower calving intervals (r2 = –0.21 P = 0.0008), but was not correlated with age at first calving (P = 0.78). Antral follicle counts were similar (P = 0.71) between heifers (38.6 ± 23.96) and cows (38.9 ± 28.00). Calving intervals were shorter in females with higher AFC (r2 = –0.17 P = 0.0064). Age was slightly related to a decrease in the AFC (r2 = –0.066 P < 0.0001). Vulva width and antral follicle count were correlated and were indicators of reproductive efficiency in females of the Tabapuã breed under the present experimental conditions. To our knowledge, this is the first report where vulva width, a fairly simple to detectable phenotype, was correlated with fertility.
142 microRNA-17-92 CLUSTER REGULATES BOVINE GRANULOSA CELL FUNCTION BY TARGETING BMPR2 AND PTEN GENES
Authors: Andreas E. , Salilew-Wondim D. , Hoelker M. , Neuhoff C. , Tholen E. , Looft C. , Schellander K. , Tesfaye D.
Published: December 2015

Normal follicular development, especially from the preantral stage until ovulation, is the critical to ensure the release of a developmentally competent oocyte. We have previously shown that among several clusters of microRNAs, microRNA-17-92 cluster (miR-17-5p, miR-19a, miR-20a, and miR-92a) is differentially expressed between bovine granulosa cells (bGC) derived from preovulatory dominant and subordinate follicles. Here, we aimed to investigate the regulatory role of microRNA-17-92 cluster in bGC function. Among the target genes predicted by the miRWalk database, BMPR2 and PTEN genes were experimentally validated using the pmirGLO Dual Luciferase Reporter Assay System (Promega Corporation, Madison, WI, USA). The bGC were aspirated from ovaries obtained from a local slaughterhouse. After determining cell viability and concentration using the trypan blue exclusion method, a total 2.5 × 105 bGC per well were seeded into CytoOne 24-well plate in DMEM/F12-Ham medium (Sigma Aldrich Chemie GmbH, Munich, Germany) supplemented with 10% FBS (Gibco BRL USA, Grand Isalnd, NY, USA) and 1% penicillin/streptomycin (Gibco BRL USA). Then, the bGC were cultured at 37°C with 5% CO2 and O2. To investigate the role of microRNA-17-92 cluster in bGC function, 100 nM of individual and cluster of microRNA-17-92 mimic, inhibitor, and negative controls were transfected into subconfluent-cultured bGC. The bGC were harvested 48 h post-transfection and used for RNA isolation and subsequent cDNA synthesis and expression analysis of candidate genes using real-time qPCR. Data analysis was performed using the comparative cycle threshold (Ct) method. A cell proliferation assay was performed using CCK-8 kit (Dojindo EU GmbH, Munich, Germany). Based on the cell diameter measurement done using ImageJ 1.48v software (National Institutes for Health, Bethesda, MD, USA), those bGC with diameter >14 µm were categorized as differentiated cells, whereas those with diameter = 14 µm were considered as undifferentiated cells. MicroRNA-17-92 cluster overexpression on bGC reduced both mRNA and protein expression of BMPR2 and PTEN genes, whereas inhibition of microRNA-17-92 cluster increased their expression. Bovine GC transfected with microRNA-17-92 cluster mimic showed higher proliferation activity and decreased rate of differentiation. The opposite phenotype was observed in bGC transfected with microRNA-17-92 cluster inhibitor. Similarly, miRNA-17-92 cluster mimic transfection increased the expression of markers of proliferation, CCND2 and PCNA, and resulted in down-regulation of CYP11A1 and STAR genes as markers of differentiation. The opposite expression pattern was observed after transfection of miRNA-17-92 cluster inhibitors. In conclusion, the miRNA-17-92 cluster members coordinately regulate bGC proliferation and differentiation by targeting the expression of BMPR2 and PTEN genes.
169 OVUM PICK-UP, IN VITRO EMBRYO PRODUCTION, AND EMBRYO TRANSFER IN CATTLE IN TROPICAL AND SUBTROPICAL MEXICO
Authors: Castañeda S. , Romo S. , Kjelland M. E.
Published: December 2015

Biotechnology continues to evolve rapidly, allowing the development of artificial reproductive techniques (ART) to increase reproductive efficiency and contribute to the genetic improvement of domestic animals. The present study examines the results obtained after 30 months of starting a commercial practice for ovum pickup (OPU) in vitro embryo production (IVP) and embryo transfer (ET) in cattle in tropical and subtropical Mexico. This research was conducted from 2013–2015 in beef and dairy cattle kept under different environmental and management conditions in 6 states (Chiapas, Oaxaca, Tabasco, Tamaulipas, Veracruz, and Yucatan). Oocytes were collected by OPU, without hormonal treatment, from 10 donor cows: 2 Bos taurus (Bt), 5 Bos indicus (Bi), and 3 Bt × Bi. A total of 98 oocyte recovery sessions were performed on 756 cows and produced 12 524 viable oocytes (1349 GI, 3383 GII, 7792 GIII), which were sent to a central laboratory for IVP. Both conventional and sexed semen were used for IVF, from 9 breeds: 2 Bt, 5 Bi and 2 Bt × Bi. The overall cleavage rate was 69% (8587/12 524). The embryo production efficiency rate was 31% (3905/12 524). Fresh sexed and conventional embryos were transferred to recipients synchronised with the following protocol: Day 0, application of an intravaginal device (ID) with progesterone and 2 mg of oestradiol benzoate IM; Day 8, removal of the ID, 400 IU eCG IM, 0.5 mg cloprostenol sodium IM, and 0.5 mg oestradiol cipionate IM. Day 10 was considered the day of oestrus. Pregnancy rate after ET was 38% (945/3905). The average number of viable oocytes per donor cow was 16.57; the average number of transferred embryos per donor cow was 5.17, and the average number of pregnancies per donor cow was 1.25. The OPU-IVP were successful in producing pregnancies even under several adverse conditions, such as a tropical environment, many donors being prepuberal females and the majority of the adult cows having a previous non-productive history due to hormonal mishandling in superovulation programs or because of overfeeding for show purposes. The consequences of these factors can be observed in the lower overall cleavage rate obtained (69%), compared to the expected (75%). Some variables require further analysis (e.g. different OPU and ET technicians, time of year, cow age, cow breed, and use of conventional and sexed semen). A successful IVP practice has to face and overcome multiple problems that may arise in some geographic locations but, perhaps, not in others. It is interesting to note the use of sexed versus conventional embryos, of the 98 ET sessions, 25 involved sexed embryos versus 73 for conventional embryos. The use of sexed semen for OPU-IVP and ET in this region of Mexico continues to expand.
We thank Genemex Internacional and the ranch owners that were involved with this research.
172 ANTIVIRAL ACTION OF PROPOLIS AQUEOUS EXTRACT DURING MATURATION OF INFECTED BOVINE OOCYTES
Authors: Palazzi E. G. , Hansen D. , Alves M. F. , Nogueira A. H. C. , Ogata R. A. , Bersano J. G. , Pacheco L. P. , de Stefano E. , Okuda L. H. , Jordão R. S. , Pituco E. M.
Published: December 2015

The objective of this study was to evaluate the decrease of virus replication in BoHV-1 (Colorado strain, 106.5 TCID50/mL) after the treatment using propolis aqueous extract (PAE) during in vitro maturation of infected bovine oocytes (24 h). Cow ovaries were obtained from a local slaughterhouse (Nelore breed) and transported to the laboratory. Cumulus-oocyte complexes (COC) were aspirated from follicles and separated into 4 groups (number of replicates for all groups = 6), which were exposed to 20 μL of sterile physiological solution (SPS), 100 μL of the in vitro maturation (IVM) medium [G1 (control), n = 609]; 10 μL of BoHV-1 (106.5 TCID50/mL) virus, 100 μL IVM medium, and 10 μL of SPS (G2, n = 786); 10 μL of PAE in 0.001% in SPS, 100 μL IVM medium, and 10 μL of SPS (G3, n = 819); 10 μL of PAE extract in 0.001% in SPS, 10 μL of BoHV-1 (106.5 TCID50/mL) virus and 100 μL of the IVM medium (G4, n = 734). All groups were kept for 24 h at 38.5°C, 5% CO2 in air. After the IVM, we analysed COC expansion and the presence of a polar body by optical microscope as well as viral replication by titration (Reed and Muench test) after 72 h of co-culture with Madin-Darby bovine kidney (MDBK) cells. The G1, G3, and G4 showed steady expansion of the cumulus cells and ooplasm with uniform appearance. The G2 did not have expansion of the cumulus cells. In contrast, the cytoplasm showed degenerative appearance and an absence of maturity in numerous oocytes. The maturation rates were as follows: G1 = 79% (482/609), G2 = 51% (407/786), G3 = 80% (662/819), and G4 = 76% (565/734). The differences among groups in maturation rates were compared using the chi-squared test (α = 5%) and the average titrations using the Mann–Whitney test (α = 5%). There was a significant difference (P < 0.01) among G1 and G2 evincing the interference of the virus maturation. The extract did not affect maturation as there was no difference among G1 and G3 (P = 0.43). The main step was finding no significant difference between the groups G1 and G4, (P = 17) proving that the extract interferes with viral replication. The titration after co-culturing the oocytes in MDBK demonstrated that G4 (average titrations = 1.63 × 103 titration) showed a lower rate of viral replication, the Mann-Whitney test, when compared to group G2 (average titrations = 6.04 × 107) which has not been subjected to treatment with PAE (P = 0.02). These results indicate that the propolis aqueous extract reduces the rate of viral replication without interfering with the maturation of oocytes and, therefore, it can be a conclusion that the analysis of the action of the molecules of this extract (by proteomics, for example) and future studies should be directed towards identifying the effect of extract on antiviral activity during the assessment of oocyte competence and embryo development.