Review: What have we learned about the effects of heat stress on the pig industry?

Pig production faces seasonal fluctuations. The low farrowing rate of sows mated in summer, increased carcass fatness of progeny born to the sows mated in summer, and slower growth rate of finisher pigs in summer are three economically important impacts identified in the pig industry. The purpose of this review is to examine advances over the past decade in understanding the mechanisms underlying the three impacts associated with summer conditions, particularly heat stress (HS), and to provide possible amelioration strategies. For impact 1, summer mating results in low farrowing rates mainly caused by the high frequency of early pregnancy disruptions. The contributions of semen DNA damage, poor oocyte quality, local progesterone concentrations, and suboptimal embryonic oestrogen secretion are discussed, as these all may contribute to HS-mediated effects around conception. Despite this, it is still unclear what the underlying mechanisms might be and thus, there is currently a lack of commercially viable solutions. For impact 2, there have been recent advances in the understanding of gestational HS on both the sow and foetus, with gestational HS implicated in decreased foetal muscle fibre number, a greater proportion of lighter piglets, and increased carcass fatness at slaughter. So far, no effective strategies have been developed to mitigate the impacts associated with gestational HS on foetuses. For impact 3, the slowed growth rate of pigs during summer is one reason for the reduced carcass weights in summer. Studies have shown that the reduction in growth rates may be due to more than reductions in feed intake alone, and the impaired intestinal barrier function and inflammatory response may also play a role. In addition, it is consistently reported that HS attenuates fat mobilisation which can potentially exacerbate carcass fatness when carcass weight is increased. Novel feed additives have exhibited the potential to reduce the impacts of HS on intestinal barrier function in grower pigs. Collectively, based on these three impacts, the economic loss associated with HS can be estimated. A review of these impacts is warranted to better align the future research directions with the needs of the pig industry. Ultimately, a better understanding of the underlying mechanisms and continuous investments in developing commercially viable strategies to combat HS will benefit the pig industry.

Application of deep learning to auto-delineation of target volumes and organs at risk in radiotherapy

The technological advancement heralded the arrival of precision radiotherapy (RT), thereby increasing the therapeutic ratio and decreasing the side effects from treatment. Contour of target volumes (TV) and organs at risk (OARs) in RT is a complicated process. In recent years, automatic contouring of TV and OARs has rapidly developed due to the advances in deep learning (DL). This technology has the potential to save time and to reduce intra- or inter-observer variability. In this paper, the authors provide an overview of RT, introduce the concept of DL, summarize the data characteristics of the included literature, summarize the possible challenges for DL in the future, and discuss the possible research directions.

[Research of the certified reference material of mecury in lyophilized bovine blood]

Objective: To develop a reference material for the analysis of mercury in freeze-dried bovine blood. Methods: The whole blood of the bovine was collected, mercury standard solution was added, After mixing, packaging and freeze-drying. Two concentration levels of reference materials were prepared. The homogeneity and stability were evaluated by t-test and F-test methods respectively. The uncertainty in preparation, long-term stability, short-term stability and fixed value were evaluated Evaluation and assignment of reference materials. The research products were fixed value and were analyzed by two methods and fixed value in 9 laboratories and the uncertainty during development was analyzed. Results: The reference material has good uniformity and can be kept stably for 12 months at -20 ℃; When transported at ≤35 ℃, the quantity value is stable within 7 days; After re dissolution, it can be stored at 4 ℃ for 5 days; The values are 9.4 respectively μg/L and 29.2 μg/L, and the uncertainty is ±1.1 respectively μg/L and ±2.3 μg/L (k=2) . Conclusion: The indexes of reference materials for mercury composition analysis in freeze-dried bovine blood meet the requirements of technical specifications and have certain application value.

Curcumin attenuates renal ischemia reperfusion injury via JNK pathway with the involvement of p300/CBP-mediated histone acetylation

Apoptosis is proved responsible for renal damage during ischemia/reperfusion. The regulation for renal apoptosis induced by ischemia/reperfusion injury (IRI) has still been unclearly characterized to date. In the present study, we investigated the regulation of histone acetylation on IRI-induced renal apoptosis and the molecular mechanisms in rats with the application of curcumin possessing a variety of biological activities involving inhibition of apoptosis. Sprague–Dawley rats were randomized into four experimental groups (SHAM, IRI, curcumin, SP600125). Results showed that curcumin significantly decreased renal apoptosis and caspase-3/-9 expression and enhanced renal function in IRI rats. Treatment with curcumin in IRI rats also led to the decrease in expression of p300/cyclic AMP response element-binding protein (CBP) and activity of histone acetyltransferases (HATs). Reduced histone H3 lysine 9 (H3K9) acetylation was found near the promoter region of caspase-3/-9 after curcumin treatment. In a similar way, SP600125, an inhibitor of c-Jun N-terminal kinase (JNK), also attenuated renal apoptosis and enhanced renal function in IRI rats. In addition, SP600125 suppressed the binding level of p300/CBP and H3K9 acetylation near the promoter region of caspase-3/-9, and curcumin could inhibit JNK phosphorylation like SP600125. These results indicate that curcumin could attenuate renal IRI via JNK/p300/CBP-mediated anti-apoptosis signaling.

P–602 Pregnancy outcomes of progestin primed ovarian stimulation protocol, GnRH antagonist protocol and GnRH agonist protocol for young patients undergoing PGT-M

Study question

To investigate the pregnancy outcomes of progestin primed ovarian stimulation protocol, GnRH antagonist protocol and GnRH agonist protocol for young patients undergoing preimplantation genetic testing for monogenic gene diseases.

Summary answer

PPOS protocol could reduce the normal chromosome formation and further development potential of embryos, suggesting that the PPOS protocol should be used cautiously.

What is known already

GnRH antagonist protocol (GnRHant) and GnRH agonist protocol (GnRHa) have been used in clinic for many years as routine regimens, and their ovarian stimulation effects and pregnancy outcomes have been confirmed by a large number of literatures. As a new protocol in recent years, the reports of pregnancy outcomes of progestin primed ovarian stimulation protocol (PPOS) are inconsistent.

Study design, size, duration

This retrospective cohort study was performed in a reproduction center from a tertiary hospital between September 2018 and November 2020 which included 147 young patients (<35 year old) undergoing preimplantation genetic testing for monogenic gene diseases (PGT-M) after stimulated by progestin primed ovarian stimulation protocol (n = 44), GnRH antagonist protocol (n = 60) or GnRH agonist protocol (n = 43).

Participants/materials, setting, methods

This study included 147 young patients (<35 year old) undergoing preimplantation genetic testing for monogenic gene diseases (PGT-M) after stimulated by progestin primed ovarian stimulation protocol (PPOS, n = 44), GnRH antagonist protocol (GnRHant, n = 60) or GnRH agonist protocol (GnRHa, n = 43). The primary outcomes were normal karyotype embryo rate and live birth rate. The embryological and clinical outcomes were measured.

Main results and the role of chance

Basic characteristics such as infertility duration, age, and body mass index (BMI) were comparable in study groups. No significant difference was found in the number oocytes retrieved or viable embryos between the groups.

Normal karyotype embryo rate of PPOS protocol was significantly lower than GnRHant and GnRHa protocol (57.6% for PPOS vs 76.0% for GnRHant vs 67.3% for GnRHa).

No significant difference were found in chemical pregnancy rate (77.3% for PPOS vs 73.3% for GnRHant vs 74.4% for GnRHa) or clinical pregnancy rate (69.8% for PPOS vs 71.7% for GnRHant vs 72.5% for GnRHa). While live birth rate of PPOS protocol was significantly lower than GnRHant and GnRHa protocol ( 45.5% for PPOS vs 58.3% for GnRHant vs 72.2% for GnRHa).

Limitations, reasons for caution

This is a preliminary study which needs to be further confirmed by large-scale clinical studies.

Wider implications of the findings: Although this is a preliminary study which needs to be further confirmed by large-scale clinical studies, the current results suggest that the application of PPOS should be cautious.

Trial registration number

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Genome-wide epistatic interactions of litter size at birth in Chinese indigenous pigs

Improving litter size at birth (TNB) and the number of piglets born alive (NBA) are the main breeding goals related to litter traits, which are economically important. A better understanding of genetic architecture underlying TNB and NBA traits could increase pig production efficiency. However, most previous studies on these traits focus on additive genetic effects, while epistatic interactions underlying TNB and NBA traits has not yet been well investigated, which are essential to understand how traits-related genes interact. Herein, we conducted genome scans of epistatic interactions underlying TNB and NBA traits in a total of 150 Chinese indigenous pigs (75 Jinhua and 75 Shengxian Spotted pigs) with high throughput genomic data. Based on SNPs with high interaction values and connectivity scores, we identified eight promising candidate genes (AKT2, TSC1, MTOR, PIK3R5, TIAM1, FGF14, RALB and ROR2) potentially associated with litter traits in pigs. Moreover, the underlying pathways, e.g., calcium ion transport, pointed out their roles in litter size-related traits. Our findings provide new insight into genetic architecture of litter traits in pigs and will benefit economic profits in pig production.

[Design, screening and antibacterial activity evaluation of the novel antibacterial peptide KR-1]

OBJECTIVE

To design novel antimicrobial peptides with high activity and low toxicity and evaluate their effect against Streptococcus mutans and other oral bacteria for prevention and treatment of dental caries.

OBJECTIVE

We synthesized two antimicrobial peptides (KR-1 and KR-2) using Dhvar4 (a histatins5 mimic) as the template. The antimicrobial peptides with high activity and low toxicity were screened using minimal inhibitory concentration (MIC) test, hemolysis test, and CCK-8 assay. Streptococcus mutans biofilms cultured in 96-well plates were divided into experimental group (KR-1) and positive control group (CHX) and treated with concentration gradients (0.6×, 0.8×, 1× and 2× MICs) of KR-1 and CHX, respectively. Crystal violet staining was used for quantitative analysis of the changes of the biofilms after the treatments. The structural changes of the biofilms were observed with laser confocal microscopy after KR-1 treatment at 10 × MIC. The antimicrobial activity of KR-1 against oral Streptococcus was analyzed based on the time required for sterilization after KR-1 treatment.

OBJECTIVE

The MIC of KR-1 and KR-2 for S. mutans was 3.2 μmol/L and 12.8 μmol/L, respectively. Under the effective concentration, KR-1 and KR-2 resulted in hemolysis rates of 0.35% and 48.8% in rabbit red blood cells and lowered the survival rates of gingival fibroblasts to 88.7% and 21.94%, respectively. KR-1 treatment significantly reduced biofilm formation with a minimum biofilm inhibition concentration (MBIC₅₀) lower than 1.92 μmol/L, and showed an even stronger antimicrobial than CHX at the concentration of 2.56 μmol/L (P=0.001). Confocal laser scanning microscopy revealed that the biofilm structure became loosened after KR-1 treatment, which was capable of killing about 90% of the bacteria within 5 min.

OBJECTIVE

The antimicrobial peptide KR-1 has a stronger antibacterial activity and a low toxicity with a good inhibitory effect against S. mutans biofilm.

Distinct Regionalization Patterns of Cortical Morphology are Associated with Cognitive Performance Across Different Domains

Cognitive performance in children is predictive of academic and social outcomes; therefore, understanding neurobiological mechanisms underlying individual differences in cognition during development may be important for improving quality of life. The belief that a single, psychological construct underlies many cognitive processes is pervasive throughout society. However, it is unclear if there is a consistent neural substrate underlying many cognitive processes. Here, we show that a distributed configuration of cortical surface area and apparent thickness, when controlling for global imaging measures, is differentially associated with cognitive performance on different types of tasks in a large sample (N = 10 145) of 9-11-year-old children from the Adolescent Brain and Cognitive DevelopmentSM (ABCD) study. The minimal overlap in these regionalization patterns of association has implications for competing theories about developing intellectual functions. Surprisingly, not controlling for sociodemographic factors increased the similarity between these regionalization patterns. This highlights the importance of understanding the shared variance between sociodemographic factors, cognition and brain structure, particularly with a population-based sample such as ABCD.

LncRNA NORAD stimulates proliferation and migration of renal cancer via activating the miR-144-3p/MYCN axis

OBJECTIVE

The purpose of this study was to clarify the potential role of long non-coding RNA (lncRNA) NORAD in the development of renal cancer.

PATIENTS AND METHODS

Expression levels of NORAD, miR-144-3p, and MYCN in renal cancer tissues and cell lines were detected. After overexpression of NORAD, proliferative and migratory changes in ACHN and A498 cells were evaluated by Cell Counting Kit-8 (CCK-8) and transwell assay, respectively. Thereafter, Luciferase assay was conducted to determine the interaction in the NORAD/miR-144-3p/MYCN axis. Besides, its biological function in influencing phenotype changes of renal cancer cells was finally demonstrated by rescue experiments.

RESULTS

The results manifested that NORAD and MYCN were upregulated, while miR-144-3p was downregulated in renal cancer tissues. Overexpression of NORAD stimulated proliferative and migratory potentials in ACHN and A498 cells, which were partially abolished by co-overexpression of miR-144-3p. Moreover, NORAD/miR-144-3p/MYCN axis was found to be responsible for stimulating the malignant development of renal cancer.

CONCLUSIONS

LncRNA NORAD stimulates proliferative and migratory potentials in renal cancer by sponging miR-144-3p to upregulate MYCN.