Global proteomic analysis of serum during early pregnancy in the pig using data-independent acquisition mass spectrometry with verification by parallel reaction monitoring.

CONTEXT: The current pregnancy diagnosis is generally not ideal in accuracy and efficiency, and the physiological process of early pregnancy in pig remains unclarified. AIMS: This study aimed to evaluate protein expression profiles and identify typical proteins of early pregnancy for more understanding of physiological processes. METHODS: Data-independent acquisition-based (DIA) quantitative proteomic analysiswas performed to compare the serum proteome profiles on days 0, 5, 12, 16, and 19 of gestation in Tibetan pig.Parallel reaction monitoring (PRM) was subsequently performed to verify relative expression level. KEY RESULTS: 396 proteins were detected, of which 113 differentially expressed proteins (DEPs) were identified. Functional annotation and pathway analysis indicated that the DEPs were mainly involved in catalytic activity, metabolic processes and the proteasome. Four candidate DEPs (talin 1, profilin, carbonic anhydrase, and HGF activator) showed consistent expression trends in both DIA and PRM approaches. CONCLUSIONS: The DIA based proteomic methods indicate the involvement of numerous serum proteins in early pregnancy physiological function in pigs. The combination of DIA-PRM based global proteomic analysis may provide insights for function study and pregnancy diagnosis biomarkers. IMPLICATIONS: The global proteomic analyses performed here have increased the knowledge of early pregnancy in Tibetan swine and provide potential methods for pregnancy detection.

Computationally efficient 104 Gb/s PWL-Volterra equalized 2D-TCM-PAM8 in dispersion unmanaged DML-DD system.

Two-dimensional eight-level pulse amplitude modulation with trellis-coded modulation (2D-TCM-PAM8) is proposed to overcome the bandwidth limitation for high-speed signal transmission due to its high spectral efficiency. However, the high coding gain of the TCM can only be achieved in bandlimited additive white Gaussian noise (AWGN) channels and cannot be achieved in nonlinear channels without any equalizers. In the directly modulated laser and direct detection (DML-DD) transmission system, the transceiver nonlinearities and the interaction between DML chirp and fiber dispersion will introduce nonlinear distortion. To compensate for the nonlinear distortion, we propose a computationally efficient piecewise linear (PWL)-Volterra equalizer. In this equalizer, we first use the PWL to correct the skewed eye diagram and then employ a simple 2nd order Volterra to compensate for the residual nonlinear distortions. By using the PWL-Volterra equalizer prior to the Viterbi decoder, the high coding gain of TCM can be achieved. In the experiment, a 104 Gb/s 8-state 2D-TCM-PAM8 signal generated in a ∼ 20 GHz DML is successfully transmitted over 10 km standard single-mode fiber (SSMF) in C band, with the bit error ratio (BER) below the HD-FEC limit of 3.8 × 10-3. Compared to only using the conventional 2nd order Volterra equalizer with a similar BER performance, the PWL-Volterra equalizer shows 29% computational complexity reduction.

Nonlinear Tomlinson-Harashima precoding for direct-detected double sideband PAM-4 transmission without dispersion compensation.

In this paper, we propose a nonlinear Tomlinson-Harashima pre-coding (THP) scheme for nonlinear distortion suppression in direct-detected double sideband (DSB) PAM-4 transmission systems. Based on the traditional THP, the feedback term is modified by introducing nonlinear components. In this way, more accurate feedback can be obtained to mitigate the signal distortions, especially the nonlinear distortions including the signal-to-signal beating interference and nonlinear power series caused by chromatic dispersion and square-law detection. Meanwhile, we also propose to only reserve the nonlinear kernels with adjacent tap products in nonlinear THP, for the purpose of computation complexity reduction. To verify the effectiveness, transmissions of double sideband (DSB) PAM-4 signal in 1550nm window are experimentally demonstrated. Volterra FFE is adopted on the receiver side to suppress linear and nonlinear pre-cursors. We optimize various parameters of hardware and apply appropriate simplification to the nonlinear THP kernels. The results indicate that, the proposed nonlinear THP can lead to up to three folds BER reduction, compared to the conventional linear THP. Finally, with the combination of proposed nonlinear THP and conventional Volterra FFE, we successfully transmit 84-Gbps PAM-4 and 107-Gbps PAM-4 respectively over 80 km and 40 km under the hard decision forward error correction (HD-FEC) threshold of 3.8 × 10-3.

Performance comparison of DML, EML and MZM in dispersion-unmanaged short reach transmissions with digital signal processing.

In this paper, transmission performances of directly modulated laser (DML), electro-absorption modulated laser (EML) and Mach-Zehnder modulator (MZM) are experimentally compared in dispersion-unmanaged high-speed transmission systems with digital signal processing (DSP). We show that, although the DML based transmitter is often believed to be less favorable in C-band high-speed transmissions, it exhibits superior performance over the other two transmitters when either linear or nonlinear digital signal processing is adopted. By theoretical and experimental analysis, we reveal that the superiority of DML can be attributed to the compensation of fiber power fading by its inherent adiabatic chirp as well as the mitigation of chirp induced distortions by the linear or nonlinear equalization. Experimental results of 56Gb/s 4-level pulse amplitude modulation (PAM4) signals under various equalization schemes including linear feedforward equalization, simplified nonlinear Volterra equalization and partial response signaling are presented. Particularly, we show that for DML a 40km transmission distance can be achieved to satisfy the extended range-4 (ER4) Ethernet interconnect using a simplified Volterra equalizer, and a 20km transmission distance can be supported using a linear equalizer. In contrast, for MZM and EML, the achievable transmission distances are respectively 20km and 15km using the Volterra equalizer, respectively, and 15km and 10km using linear equalizer, respectively. Moreover, we show that even using the combination of the Volterra equalizer and partial response signaling, the transmission distances of MZM and EML based systems are limited to 30km and 20km.

Design and analysis of high-speed optical access networks in the O-band with DSP-free ONUs and low-bandwidth optics.

In this paper, we demonstrate and investigate high-speed passive optical networks (PON) in the O-band without using any digital signal processing (DSP) at the ONU side, meanwhile still adopting cost-effective low-bandwidth optics. We show that with commercial 10G-class optics including DML and PIN-TIA, 50Gb/s PAM4 PON with a power budget up to 29dB is achieved under the HD-FEC BER limit. We present the detailed design procedure of the DSP including the downlink Nyquist pulse shaping and pre-equalization and uplink post-equalization, and conduct a comprehensive study on this system including DSP complexity, DAC/ADC sampling rate requirement and tolerance to the response diversity of ONU receivers. We conclude that, 1) 55 and 35 taps are sufficient for downlink and uplink digital filters to approach the BER floor; 2) the minimum required DAC and ADC sampling rate are respectively 33.75GS/s and 32GS/s to achieve the optimal performance; and 3) with 1dB sensitivity penalty at the HD-FEC BER limit, the allowable response diversity of ONU receivers can be from -2.2dB/10GHz to 1.8dB/10GHz. Furthermore, we explore and demonstrate the suitable data rate based on on-off keying and duobinary modulation formats in this system and present corresponding results.

Impact of SOA-induced pattern effect on the filter requirements in vestigial sideband direct detected PAM4 transmission.

In an optical filter based VSB-DD transmission system, semiconductor optical amplifier (SOA) is a promising option to enhance system optical power margin. While, in practical system, the low input saturation power makes the SOA-amplified signal susceptible to the pattern effect, which causes a considerable spectral broadening, thereby influencing the design of VSB filter. In this paper, the relationship between SOA-induced pattern effect and the requirements of the VSB filter is systematically investigated. Firstly, qualitative analysis is given and upper sideband (USB) is proved better than lower sideband (LSB) owing to the suppression of SOA-induced pattern effect. Then, 56Gbps IM/DD PAM4 transmission is experimentally conducted. With respective optimal filter configuration, performance of USB signal is superior to LSB signal in all cases. Results show that USB signal has 1dB sensitivity superiority to LSB signal for 56Gb/s PAM4 after 40km transmission. And in 80km case, only by using USB signal, can HD-FEC limit (3.8 × 10-3) be achieved. Also, we study requirements on other filter parameters, including redundant bandwidth and filter steepness.

High tolerance against chirp induced distortions in PAM4-based digital mobile fronthaul by sample bits interleaving.

Directly modulated lasers (DMLs) and electro-absorption modulated lasers (EMLs) are key transmitter options in future short-haul networks. However, both of them suffer from frequency chirp, which incurs nonlinear distortions, especially to high order modulation signals. In this paper, we investigate their application in PAM4-based digital mobile fronthaul and propose a scheme to remarkably improve the fidelity of radio signal. We first give a detailed study of the BER distribution of DML/EML based PAM4 signals and find that the BER of the second bit is much higher than that of the first bit in both systems. Accordingly, we propose to adopt sample bit interleaving to reduce the radio signal distortions caused by sample bit errors. Experimental results of 56Gbps I/Q data transmission reveal that, in a DML-based transmission system, the proposed scheme respectively leads to up to 8dB and 13dB EVM reduction to accommodate 33 × 100MHz 1024QAM OFDM signals and 64QAM OFDM signals in 10km and 20km cases. As well as in an EML-based transmission system, 14dB EVM reduction is achieved in 10km to finally accommodate 33 × 100MHz 256QAM OFDM signal.

Fidelity enhancement in high-data-rate digital mobile fronthaul with sample bits interleaving and unequally-spaced PAM4.

Driven by continuously growing mobile traffic, line rate of digital mobile fronthaul (MFH) network keeps surging. 4-level pulse amplitude modulation (PAM4) is a promising format to provide such high data capacity, due to its bandwidth and cost efficiency. In this paper, we propose an improved method to reduce mobile signal distortion caused by bit error of optical transmission. The concept comes from the characteristic that high order sample bit error induces far severer performance degradation to radio signal than low order one. In the solution, high order sample bits and low order sample bits are interleaved, so that they are respectively mapped to first bit (1stb) and second bit (2ndb) of PAM4 symbol. On the other hand, amplitude levels of PAM4 are set unequal to broaden the "middle eye", levering accuracy of 1stb. Hence, the total fidelity of mobile signal is enhanced. The feasibility is confirmed both theoretically and experimentally. The investigation is based on two typical digital systems, i.e., 16-bit uniform quantizing and 8-bit nonuniform quantizing. Experimental results indicate that, EVM of LTE-A like radio signal decreases by up to 13dB in uniform quantizing system, and by up to 5dB in nonuniform quantizing system, compared with conventional equally-spaced PAM4.

Novel perspectives on autophagy-oxidative stress-inflammation axis in the orchestration of adipogenesis.

Adipose tissue, an indispensable organ, fulfils the pivotal role of energy storage and metabolism and is instrumental in maintaining the dynamic equilibrium of energy and health of the organism. Adipocyte hypertrophy and adipocyte hyperplasia (adipogenesis) are the two primary mechanisms of fat deposition. Mature adipocytes are obtained by differentiating mesenchymal stem cells into preadipocytes and redifferentiation. However, the mechanisms orchestrating adipogenesis remain unclear. Autophagy, an alternative cell death pathway that sustains intracellular energy homeostasis through the degradation of cellular components, is implicated in regulating adipogenesis. Furthermore, adipose tissue functions as an endocrine organ, producing various cytokines, and certain inflammatory factors, in turn, modulate autophagy and adipogenesis. Additionally, autophagy influences intracellular redox homeostasis by regulating reactive oxygen species, which play pivotal roles in adipogenesis. There is a growing interest in exploring the involvement of autophagy, inflammation, and oxidative stress in adipogenesis. The present manuscript reviews the impact of autophagy, oxidative stress, and inflammation on the regulation of adipogenesis and, for the first time, discusses their interactions during adipogenesis. An integrated analysis of the role of autophagy, inflammation and oxidative stress will contribute to elucidating the mechanisms of adipogenesis and expediting the exploration of molecular targets for treating obesity-related metabolic disorders.

Quantitative proteomic analysis and verification identify global protein profiling dynamics in pig during the estrous cycle.

The current estrus detection method is generally time-consuming and has low accuracy. As such, a deeper understanding of the physiological processes during the estrous cycle accelerates the development of estrus detection efficiency and accuracy. In this study, the label-free acquisition mass spectrometry was used to explore salivary proteome profiles during the estrous cycle (day -3, day 0, day 3, and day 8) in pigs, and the parallel reaction monitoring (PRM) was applied to verify the relative profiles of protein expression. A total of 1,155 proteins were identified in the label-free analysis, of which 115 were identified as differentially expressed proteins (DEPs) among different groups (p ≤ 0.05). Functional annotation revealed that the DEPs were clustered in calcium ion binding, actin cytoskeleton, and lyase activity. PRM verified the relative profiles of protein expression, in which PHB domain-containing protein, growth factor receptor-bound protein 2, elongation factor Tu, carboxypeptidase D, carbonic anhydrase, and trefoil factor 3 were confirmed to be consistent in both label-free and PRM approaches. Comparative proteomic assays on saliva would increase our knowledge of the estrous cycle in sows and provide potential methods for estrus detection.

The Effects of Dietary Inclusion of Mulberry Leaf Powder on Growth Performance, Carcass Traits and Meat Quality of Tibetan Pigs.

This research was conducted to study the effects of dietary inclusion of mulberry leaf powder (MLP) on growth performance, meat quality, antioxidant activity, and carcass traits of Tibetan pigs. Eighteen Tibetan pigs (33.8 ± 1.1 kg) were assigned to two treatment groups randomly and received either the control diet (CON) or a basal diet containing 8% MLP (MLP) for two months. After the two-month feeding trial, the MLP group showed lower backfat thickness while a higher lean percentage. Compared with CON pigs, MLP pigs had higher serum CAT activity. In addition, dietary MLP supplementation significantly decreased the muscle shear force. Muscle fiber morphology analysis showed that MLP pigs had larger muscle fiber density while smaller muscle fiber cross-sectional area. Up-regulated gene expression of myosin heavy chain (MyHC)IIa was also observed in MLP pigs. These results indicate that the enhanced antioxidant activity and altered muscle fiber type and morphology appeared to contribute to the improvement of meat quality in Tibetan pigs fed diets containing MLP.

Identification and expression of X-linked inhibitor of apoptosis protein during follicular development in goat ovary.

X-linked inhibitor of apoptosis protein (XIAP), an endogenous of inhibitor of caspases, plays crucial roles in regulating ovarian granulosa cell apoptosis during follicular atresia. The aim of the present study was to determine the presence and localization of XIAP in the goat ovary and its expression level during follicular development. The full length cDNA of XIAP from goat ovary cells was cloned using reverse transcription PCR. A total of 497 amino acid residues were encoded by open reading frame and had high identity with homologous sequences from other mammals. XIAP was widely expressed in adult goat tissues as determined by real-time PCR and it demonstrated higher expression in propagative organs. High level of XIAP was detected in large healthy follicles and corpus luteum in comparison with that in small antral follicles, which was in accordance with the immunohistochemistry results and atretic follicles had very low expression. XIAP was localized in both granulosa and theca cells in antral follicles but not in primordial follicles. Furthermore, luteinizing hormone stimulated the proliferation of mRNA encoding XIAP in granulosa cells in vitro. The present study demonstrated that XIAP was expressed in a follicular-stage-dependent manner in goat ovaries.

Development of a Curative Therapeutic Vaccine (TheraVac) for the Treatment of Large Established Tumors.

Harnessing immune system to treat cancer requires simultaneous generation of tumor-specific CTLs and curtailment of tumor immunosuppressive environment. Here, we developed an immunotherapeutic regimen capable of eliminating large established mouse tumors using HMGN1, a DC-activating TLR4 agonist capable of inducing anti-tumor immunity. Intratumoral delivery of HMGN1 with low dose of Cytoxan cured mice bearing small (∅ ≈ 0.5 cm), but not large (∅ ≈ 1.0 cm) CT26 tumors. Screening for activators capable of synergizing with HMGN1 in activating DC identified R848. Intratumoral delivery of HMGN1 and R848 plus Cytoxan eradicated large established CT26 tumors. The resultant tumor-free mice were resistant to subsequent challenge with CT26, indicating the generation of CT26-specific protective immunity. This immunotherapeutic regimen caused homing of tumor-infiltrating DC to draining lymph nodes and increased infiltration of T cells into tumor tissues. Cytoxan in this regimen could be replaced by anti-CTLA4) or anti-PD-L1. Importantly, this immunotherapeutic regimen was also curative for large established mouse Renca and EG7 tumors. Thus, we have developed a curative therapeutic vaccination regimen dubbed 'TheraVac' consisting of HMGN1 and R848 plus a checkpoint inhibitor, that can, without using exogenous tumor-associated antigen(s), eliminate various large tumors and induce tumor-specific immunity.

Isolation and characterisation of a novel antibacterial peptide from a native swine intestinal tract-derived bacterium.

Antimicrobial peptides (AMPs) are highly associated with antipathogenic activity, without generating drug resistance in targeted bacteria. In this study, the existence of AMPs in the Tibetan swine, a China-native, cold-resistant and seldom-sick breed of pig, was investigated. A peptide secreted by a Tibetan swine intestinal tract-derived Bacillus strain was isolated using reversed-phase chromatography (RPC), ultrafiltration and reversed-phase high-performance liquid chromatography (RP-HPLC). The peptide was identified by mass spectrometry and was characterised for activity against Escherichia coli and Staphylococcus aureus. The 16-amino acid peptide (ASVVNKLTGGVAGLLK), named TP, had a molecular mass of 1568.919 Da and exhibited inhibitory activity against Gram-positive and Gram-negative bacteria [minimum inhibitory concentrations (MICs) of 2.5-5 µM and 10-20 µM for E. coli and S. aureus, respectively] as well as human MKN-45 and NB4 tumour cell lines [50% inhibitory concentration (IC50) = 4.686 µM and 11.479 µM, respectively]. TP also exhibited weak haemolytic activity. Furthermore, TP enhanced cell membrane permeability and K+ outflow, bound with E. coli genomic DNA in vitro and inhibited E. coli growth. Thus, TP represents a strong candidate as an antibacterial peptide.

Improved Production of Sublancin 168 Biosynthesized by Bacillus subtilis 168 Using Chemometric Methodology and Statistical Experimental Designs.

Sublancin 168, as a distinct S-linked antimicrobial glycopeptide produced by Bacillus subtilis 168, is effective in killing specific microorganisms. However, the reported yield of sublancin 168 is at a low level of no more than 60 mg from 1 L fermentation culture of B. subtilis 168 by using the method in the literature. Thus optimization of fermentation condition for efficiently producing sublancin 168 is required. Here, Box-Behnken design was used to determine the optimal combination of three fermentation parameters, namely, corn powder, soybean meal, and temperature that were identified previously by Plackett-Burman design and the steepest ascent experiment. Subsequently, based on the response surface methodology, the quadratic regression model for optimally producing sublancin 168 was developed, and the optimal combination of culture parameters for maximum sublancin 168 production of 129.72 mg/L was determined as corn powder 28.49 g/L, soybean meal 22.99 g/L, and incubation temperature 30.8°C. The results showed that sublancin 168 production obtained experimentally was coincident with predicted value of 125.88 mg/L, and the developed model was proved to be adequate, and the aim of efficiently producing sublancin 168 was achieved.

Expression and regulation of tissue inhibitors of metalloproteinases (TIMP1 and TIMP3) in goat oviduct.

Tissue inhibitors of metalloproteinases (TIMPs) are associated with several reproductive processes, such as mammalian follicular growth, ovulation, CL formation, and embryonic development. However, the expression and function of TIMPs in goat oviducts remain unclear. This work aimed to identify TIMP1 and TIMP3 expression in the goat oviduct during the estrous cycle via immunohistochemistry, real-time polymerase chain reaction (PCR), and functional studies in cultured goat oviductal epithelial cells. Real-time PCR results demonstrated that TIMP1 and TIMP3 messenger RNAs were expressed in all goat oviductal regions at all stages of the estrous cycle. TIMP1 and TIMP3 proteins were also highly expressed in oviductal epithelial cells with very limited expression in other cell types. Oviductal epithelial cells were treated in vitro with various estradiol concentrations (1-100 nM) for 24 hours. The findings showed that TIMP1 expression increased up to 20 nM but then gradually decreased, whereas no significant effects existed among TIMP3 messenger RNA levels. Time-course studies indicated that estradiol significantly increased TIMP1 expression in a time-dependent manner from 8 hours to 24 hours. By contrast, TIMP3 expression was transiently induced in oviductal epithelial cells at 2 and 4 hours after estradiol treatment. Furthermore, treatment with TIMP1 functionally increased the viability of cultured oviductal epithelial cells. Overall, the results suggested that the differential regulation and function between TIMP1 and TIMP3 might be associated with their unique roles in fertilization and early embryonic development.

Expression and regulative function of tissue inhibitor of metalloproteinase 3 in the goat ovary and its role in cultured granulosa cells.

Tissue inhibitor of metalloproteinase 3 (TIMP3) played a key role in female reproduction. However, its expression and function in goat are still unclear. In the present study, the full-length cDNA of goat TIMP3 was cloned from adult goat ovary; meanwhile, we demonstrated that putative TIMP3 protein shared a highly conserved amino acid sequence with known mammalian homologs. Real-time PCR results showed that TIMP3 was widely expressed in the tissues of adult goat. In the ovary, increasing expression of TIMP3 mRNA was discovered during the growth process of follicle and corpus luteum. Immunohistochemistry results suggested that TIMP3 protein existed in oocytes of all types of follicles, corpus luteum and granulosa and theca cells of primary, secondary, and antral but not primordial follicles. In vitro, human chorionic gonadotropin (hCG) stimulated the expression of TIMP3 in goat granulosa cells. hCG-induced TIMP3 mRNA expression was reduced by the inhibitors of protein kinase A, protein kinase C, MAPK kinase, or p38 kinase. Functionally, over-expression of TIMP3 significantly increased apoptosis and decreased the viability of cultured granulosa cells. Knockdown of TIMP3 could decrease hCG-induced progesterone secretion and the mRNA abundance of key steroidogenic enzymes (StAR, p450scc and HSD3B) as well as ECM proteins (DCN and FN). These findings provided evidence that the hCG induced expression of TIMP3 may play an important role in regulating goat granulosa cell survival and steroidogenesis.

Identification and gene expression analyses of natriuretic peptide system in the ovary of goat (Capra hircus).

Natriuretic peptides (NPs) are involved in maintaining cardiovascular and fluid homeostasis, regulating reproductive processes and bone growth, and other numerous functions. To better understand the role of NPs in goat (Capra hircus), in the present study, full-length cDNAs of goat Nppa (natriuretic peptide precursor A), Nppb (natriuretic peptide precursor B) and Nppc (natriuretic peptide precursor C), respectively encoding ANP, BNP and CNP, were cloned from adult goat heart and ovary. The putative prepropeptide ANP (prepro-ANP) and prepro-CNP share a high amino acid sequence identity with other species. Real-time PCR showed that Nppa, Nppb and Nppc were widely expressed in adult goat tissues. The mRNA expression of Nppa and Nppb in the heart was extremely higher compared with other tissues. Nppc mRNA expression in the lung and uterus was also higher than in other tissues. The expression of Nppa, Nppb and Nppc genes was examined at different ovarian follicle stages using RT-PCR. The mRNAs of Nppa and Nppb were detected in secondary follicles as well as in COCs (cumulus-oocyte-complexes) and granulosa cells of antral follicles. However, the mRNA expression of Nppc was observed throughout ovarian follicle development, and it was especially higher in granulosa cells of antral follicles. In vitro, stimulating goat granulosa cells with FSH led to an increase in the expression of Nppc by dose- and time-dependent manners and a rapid decline was induced by LH stimulation, but the expression of Nppa and Nppb did not change after FSH or LH treatment. These results suggest that Nppc is a gonadotropin-induced gene in granulosa cells of goat ovary and CNP may be involved in the regulation of ovarian follicle development and oocyte maturation.