Swine Tissues Research Articles

Monitoring of irrigated lesion formation with single fiber based multispectral system using machine learning.

In radiofrequency ablation (RFA) treatment of cardiac arrhythmias, intraprocedural assessment of treatment efficacy relies on indirect measures of adequate tissue destruction. Direct sensing of diffuse reflectance spectral changes at the ablation site using optically integrated RFA catheters has been shown to enable accurate prediction of lesion dimensions, ex vivo. Challenges of optical guidance can be due to obtaining reliable measurements under various catheter-tissue contact orientations. In this work, addressed this limitation by assessing the feasibility of monitoring lesion progression using single-fiber reflectance spectroscopy (SFRS). A total of 110 endocardial lesions of various sizes were generated in freshly excised swine right ventricular tissue using a custom-built, irrigated SFRS-RFA catheter. Models were developed for assessing catheter-tissue contact, the presence of nontransmural or transmural lesions and lesion depth percentage. These results support the use of SFRS-based catheters for irrigated lesion assessment and motivate further exploration of using multi-SFRS catheters for omnidirectionality.

The effects of nanoplastics on adipose stromal cells from swine tissues

Plastic is one of the main sources of marine and terrestrial pollution. This material can fragment into micro- (<-5 mm) and nanoplastics (NPs) (<100 nm) following degradation. Animals are exposed to these particles by ingesting contaminated food, respiration or filtration, and transdermally. In organisms, NPs can cross biological membranes, and cause oxidative stress, cell damage, apoptosis, and endocrine interference. We previously demonstrated that polystyrene - NPs interfered with ovarian cell functions. Since reproduction involves a high energy expenditure and a crucial role is played by adipose tissue, the aim of the present study was to evaluate the effects of NPs on primary adipose stromal cells (ASCs) isolated from swine adipose tissues. In particular, the effects on cell viability, proliferation, metabolic activity, inflammatory process mediators and oxidative stress markers were assessed. The obtained results did not reveal a significant variation in cell proliferation, metabolic activity was increased (P < 0.01) but only at the lowest concentration, while viability showed a significant decrease after prolonged exposure to NPs (P < 0.01). TNF-α was increased (P < 0.05), while PAI-1 was inhibited (P < 0.001). Redox status was significantly modified; in particular, the production of O2−, H2O2 and NO was stimulated (P < 0.05), the non-enzymatic antioxidant power was reduced (P < 0.05) while catalase activity was significantly (P < 0.01) increased.

Distribution of cardiomyocyte-selective adeno-associated virus serotype 9 vectors in swine following intracoronary and intravenous infusion.

Limited reports exist regarding adeno-associated virus (AAV) biodistribution in swine. This study assessed biodistribution following antegrade intracoronary and intravenous delivery of two self-complementary serotype 9 AAV (AAV9sc) biologics designed to target signaling in the cardiomyocyte considered important for the development of heart failure. Under the control of a cardiomyocyte-specific promoter, AAV9sc.shmAKAP and AAV9sc.RBD express a small hairpin RNA for the perinuclear scaffold protein muscle A-kinase anchoring protein β (mAKAPβ) and an anchoring disruptor peptide for p90 ribosomal S6 kinase type 3 (RSK3), respectively. Quantitative PCR was used to assess viral genome (vg) delivery and transcript expression in Ossabaw and Yorkshire swine tissues. Myocardial viral delivery was 2-5 × 105 vg/µg genomic DNA (gDNA) for both infusion techniques at a dose ∼1013 vg/kg body wt, demonstrating delivery of ∼1-3 viral particles per cardiac diploid genome. Myocardial RNA levels for each expressed transgene were generally proportional to dose and genomic delivery, and comparable with levels for moderately expressed endogenous genes. Despite significant AAV9sc delivery to other tissues, including the liver, neither biologic induced toxic effects as assessed using functional, structural, and circulating cardiac and systemic markers. These results indicate successful targeted delivery of cardiomyocyte-selective viral vectors in swine without negative side effects, an important step in establishing efficacy in a preclinical experimental setting.

An image classification deep-learning algorithm for shrapnel detection from ultrasound images

Ultrasound imaging is essential for non-invasively diagnosing injuries where advanced diagnostics may not be possible. However, image interpretation remains a challenge as proper expertise may not be available. In response, artificial intelligence algorithms are being investigated to automate image analysis and diagnosis. Here, we highlight an image classification convolutional neural network for detecting shrapnel in ultrasound images. As an initial application, different shrapnel types and sizes were embedded first in a tissue mimicking phantom and then in swine thigh tissue. The algorithm architecture was optimized stepwise by minimizing validation loss and maximizing F1 score. The final algorithm design trained on tissue phantom image sets had an F1 score of 0.95 and an area under the ROC curve of 0.95. It maintained higher than a 90% accuracy for each of 8 shrapnel types. When trained only on swine image sets, the optimized algorithm format had even higher metrics: F1 and area under the ROC curve of 0.99. Overall, the algorithm developed resulted in strong classification accuracy for both the tissue phantom and animal tissue. This framework can be applied to other trauma relevant imaging applications such as internal bleeding to further simplify trauma medicine when resources and image interpretation are scarce.

Determination of 4 chlorpromazine and promethazine and their metabolites in swine tissues by liquid chromatography-tandem mass spectrometry with isotope internal standard dilution technique

To establish a rapid, accurate and sensitive method by liquid chromatography-tandem mass spectrometry with isotope internal standard dilution technique for the determination of chlorpromazine and promethazine and their metabolites in swine tissues. The swine tissues sample was extracted with acetonitrile and purified on MCX cartridge. The liquid chromatography separation was performed on an ACQUITY UFLC® HSS T3(100 mm×2.1 mm, 1.8 μm) with a linear gradient elution program of 0.1%(V/V) fomic acid-acetonitrile and 0.1%(V/V) formic acid-water solution as the mobile phase. The analytes were analyzed using ESI operating in the positive multiple reaction monitoring(MRM) mode. The limits of quantitation(LOQs) and limits of detection(LODs) for the target objects were 0.12-0.51 μg/kg and 0.04-0.17 μg/kg, respectively. The calibration curves were linear in range of 0.1-20.0 μg/L for chlorpromazine and promethazine, and 0.5-100.0 μg/L for their metabolites(chlorpromazine sulfoxide and isopropyl sulfoxide). The recoveries were between 90.8%-106.0%, and the relative standard deviations(RSDs) were between 1.9%-6.2%(n=6). The method is highly sensitive and accurate, and is suitable for the analysis of chlorpromazine and promethazine and their metabolites(chlorpromazine sulfoxide and isopropyl sulfoxide) in swine tissues.

Multiscale and Multiphysics Modeling of Anisotropic Cardiac RFCA: Experimental-Based Model Calibration via Multi-Point Temperature Measurements.

Radiofrequency catheter ablation (RFCA) is the mainstream treatment for drug-refractory cardiac fibrillation. Multiple studies demonstrated that incorrect dosage of radiofrequency energy to the myocardium could lead to uncontrolled tissue damage or treatment failure, with the consequent need for unplanned reoperations. Monitoring tissue temperature during thermal therapy and predicting the extent of lesions may improve treatment efficacy. Cardiac computational modeling represents a viable tool for identifying optimal RFCA settings, though predictability issues still limit a widespread usage of such a technology in clinical scenarios. We aim to fill this gap by assessing the influence of the intrinsic myocardial microstructure on the thermo-electric behavior at the tissue level. By performing multi-point temperature measurements on ex-vivo swine cardiac tissue samples, the experimental characterization of myocardial thermal anisotropy allowed us to assemble a fine-tuned thermo-electric material model of the cardiac tissue. We implemented a multiphysics and multiscale computational framework, encompassing thermo-electric anisotropic conduction, phase-lagging for heat transfer, and a three-state dynamical system for cellular death and lesion estimation. Our analysis resulted in a remarkable agreement between ex-vivo measurements and numerical results. Accordingly, we identified myocardium anisotropy as the driving effect on the outcomes of hyperthermic treatments. Furthermore, we characterized the complex nonlinear couplings regulating tissue behavior during RFCA, discussing model calibration, limitations, and perspectives.

First description of Eucoleus garfiai (Gallego and Mas-Coma, 1975) in wild boar (Sus scrofa) in Italy

Eucoleus garfiai (syn. Capillaria garfiai) is a nematode infecting lingual tissue of domestic and wild swine. Prevalence data for this parasite are scant and often related to accidental findings, occurring only in Japan and a few European countries. In this study, an epidemiological survey was performed in order to identify E. garfiai in wild boar from the Campania region, southern Italy. A total of 153 wild boar carcasses were inspected over the course of two hunting seasons (2019–2020). Histological examinations were performed on tongue samples fixed and stained with haematoxylin and eosin. The scraping of dorsal tongue tissue was carried out to collect adult worms for parasitological examination. Out of 153 wild boars, 40 (26.1%, 95% CI: 19.8–33.6%) tested positive for helminths and/or eggs in tongue tissues. Parasites were identified morphologically and identification was confirmed by molecular analysis of the 18S rRNA gene, showing a 99% nucleotide match with E. garfiai sequences available in literature. No statistically significant differences were found according to age, sex nor hunting province. Our findings agree with previous histopathological data confirming the low pathogenic impact of this nematode. The present study represents the first report of E. garfiai in wild boar from Italy.

Salmonella is Present in Multiple Lymph Nodes of Market Hog Carcasses at Slaughter

The presence of Salmonella in lymphoid tissue of market hogs represents a potential risk for the safety of pork products, particularly ground pork. With increased Salmonella testing standards required by the U.S. Department of Agriculture (USDA) on the horizon for the pork industry, it is important to improve understanding of Salmonella contamination within a variety of swine tissues, including lymph nodes. This study was designed to provide preliminary information about Salmonella prevalence in multiple lymph nodes within market hog carcasses at slaughter. From each carcass (n = 50), four lymph nodes were aseptically collected at slaughter: mesenteric, tracheobronchial, inguinal, and subiliac. A total of 197 lymph nodes were analyzed, with an overall Salmonella prevalence of 21.8% (n = 43). Salmonella was detected in the lymph nodes of 62% (n = 31) of carcasses, with 21.6% (n = 11) of carcasses harboring Salmonella in two or more lymph node types. Although not statistically significant (P = 0.1167), Salmonella prevalence did vary based upon lymph node type (mesenteric, 34%; inguinal, 18.4%; subiliac, 18.4%; tracheobronchial, 16.3%). This lymph node mapping study provides preliminary evidence that Salmonella can contaminate lymph nodes throughout swine and may serve as the foundation for larger lymph node mapping studies or intervention strategies at the abattoir.

Metasurface‐Based Abrupt Autofocusing Beam for Biomedical Applications

Manipulation and precise delivery of optical energies in the regions of interest within specimens require different strategies. Hence, proper control of input beam parameters is a prerequisite. One of the prominent methods is metasurface optics, capable of crafting properties of light at nanoscales. Here, the generation of an abrupt autofocusing (AAF) beam by a nanophotonic metasurface for biomedical applications is demonstrated. Fluorescence guided laser microprofiling of mouse cardiac samples is experimentally investigated, using the AAF beam to deliver optical energy selectively to specific locations. In addition, photocoagulation of ex vivo swine skin tissue is performed and observed through optical coherence tomography. The results show great potentials for integrating metasurface optics to realize miniature laser surgery instruments for wide applications in biomedicine.

Virus viability in spiked swine bone marrow tissue during above-ground burial method and under in vitro conditions.

The emergence of high consequence animal diseases usually requires managing significant mortality. A desirable aspect of any carcass management method is the ability to contain and inactivate the target pathogen. The above-ground burial (AGB) technique was recently developed and proposed as an alternative carcass management method. Here, we investigate the tenacity of swinepox virus (SwPV), as a surrogate model for African swine fever virus (ASFV) in swine carcasses during the AGB process. For this, SwPV was inoculated intrafemorally in 90 adult swine carcasses, which were subsequently disposed under AGB conditions. Bone marrow samples were recovered periodically throughout 12 months and virus viability was assessed by virus isolation (VI), whereas the presence of SwPV DNA was evaluated by quantitative polymerase chain reaction (qPCR). Additionally, an in vitro study assessed the inactivation rate of SwPV, Senecavirus A (SVA), and bovine viral diarrhoea virus (BVDV). Viral suspensions were mixed with bone marrow material and maintained at 21-23°C for 30 days. Virus viability was assessed by VI and viral titration. In the field study, SwPV remained viable only in 11 (55%) bone marrow samples collected on day 7; only viral DNA (and not infectivity) was detected afterwards. SwPV inactivation was estimated to have occurred by day 11. The in vitro testing revealed a variable tenacity of the studied viruses. The viability period was estimated in 28, 80, and 118 days, respectively, for BVDV, SwPV, and SVA. Overall, these findings indicate that the AGB technique was effective in quickly inactivating SwPV. Additionally, the SwPV inactivation rate is comparable to ASFV under field studies and poses a potential model for preliminary ASFV inactivation studies with reduced biosecurity requirements. Moreover, this study contributes to understanding the inactivation kinetics of viruses under specific conditions, which is critical when designing and applying countermeasures in case of biosecurity breaches in sites managing animal mortality.

Padrões temporais e espaciais na detecção de resíduos de medicamentos veterinários em aves e suínos no Brasil

Abstract Food Safety is an important topic for public health and international trade in food. Residues of veterinary drugs and environmental contaminants in animal products can cause diseases and acute toxicity in organisms exposed to these substances. This study evaluated official monitoring data of veterinary drug residues from the Brazilian Ministry of Agriculture, Livestock and Supply in tissues of poultry and swine in the period between 2002 and 2014 to check for hidden patterns in the occurrence of six common drugs (Closantel, Diclazuril, Nicarbazin, Sulfaquinoxaline, Doxycycline and Sulfamethazinein). The analysis of data was performed by using two machine learning methods: decision tree and neural networks, in addition to visual evaluation through graphs and maps. Contamination rates were low, varying from 0 to 0.66%. A spatial distribution pattern of detections of substances by region was identified, but no pattern of temporal distribution was observed. Nevertless, regressions showed an increase in levels when these substances were detected, so monitoring should continue. However, the results show that the products monitored during the study period presented a low risk to public health.

The Application of Pulp Tissue Derived-Exosomes in Pulp Regeneration: A Novel Cell-Homing Approach.

PurposeExosomes derived from stem cells, as an alternative to stem cells themselves, have been employed for dental pulp regeneration. However, it is not known whether exosomes can recruit host cells to the regeneration process. In this study, we built a “cell homing” model to determine whether exosomes derived from dental pulp tissue (DPT-exos) can regenerate dental pulp by recruiting the stem cells from the apical dental papilla (SCAPs).MethodsExosomes were isolated from the dental pulp tissue (DPT-exos) and dental pulp stem cells (DPC-exos) of swine. The effects of the exosomes on SCAPs were compared using CKK-8, Transwell, angiogenesis, and odontogenic induction assays. DPT-exos and DPC-exos were investigated in an in vivo “cell homing” model using swine teeth to compare their roles in pulp regeneration. To build the model, we placed SCAP-containing collagen gel at the root tip and filled the cavity of the treated dental matrix (TDM) with DPT-exos and DPC-exos-laden scaffolds, which would be expected to recruit SCAPs to the pulp cavity. The complex was then implanted subcutaneously into immunodeficient nude mice. After eight weeks, tissue samples were taken and analyzed histologically to determine whether the DPT-exos contributed to pulp regeneration through “cell homing”.ResultsExosomes were successfully extracted from dental pulp tissue and confirmed to be exosomes. In vitro tests confirmed that DPT-exos performed better than DPC-exos in promoting the migration, proliferation, and differentiation of SCAPs. Furthermore, DPT-exos recruited SCAPs to regenerate dental pulp-like connective tissue in vivo containing collagen, odontoblasts, and enriched predentin-like tissue. Blood vessel growth was demonstrated by immunofluorescence.ConclusionThis study demonstrated the ability of DPT-exos to induce SCAPs to regenerate connective tissue similar to natural dental pulp. This technique has the potential for treating pulp deficiency caused by various pulp diseases.

Impaired Glucocorticoid Receptor Signaling Aggravates Lung Injury after Hemorrhagic Shock.

We previously showed that attenuated lung injury after hemorrhagic shock (HS) coincided with enhanced levels of the glucocorticoid (GC) receptor (GR) in lung tissue of swine. Here, we investigated the effects of impaired GR signaling on the lung during resuscitated HS using a dysfunctional GR mouse model (GRdim/dim). In a mouse intensive care unit, HS led to impaired lung mechanics and aggravated lung inflammation in GRdim/dim mice compared to wildtype mice (GR+/+). After HS, high levels of the pro-inflammatory and pro-apoptotic transcription factor STAT1/pSTAT1 were found in lung samples from GRdim/dim mice. Lungs of GRdim/dim mice revealed apoptosis, most likely as consequence of reduced expression of the lung-protective Angpt1 compared to GR+/+ after HS. RNA-sequencing revealed increased expression of pro-apoptotic and cytokine-signaling associated genes in lung tissue of GRdim/dim mice. Furthermore, high levels of pro-inflammatory cytokines and iNOS were found in lungs of GRdim/dim mice. Our results indicate impaired repression of STAT1/pSTAT1 due to dysfunctional GR signaling in GRdim/dim mice, which leads to increased inflammation and apoptosis in the lungs. These data highlight the crucial role of functional GR signaling to attenuate HS-induced lung damage.

Optical coherence tomography-guided confocal Raman microspectroscopy for rapid measurements in tissues.

We report a joint system with both confocal Raman spectroscopy (CRS) and optical coherence tomography (OCT) modules capable of quickly addressing the region of interest in a tissue for targeted Raman measurements from OCT. By using an electrically tunable lens in the Raman module, the focus of the module can be adjusted to address any specific depth indicated in an OCT image in a few milliseconds. We demonstrate the performance of the joint system in the depth dependent measurements of an ex vivo swine tissue and in vivo human skin. This system can be useful in measuring samples embedded with small targets, for example, to identify tumors in skin in vivo and assessment of tumor margins, in which OCT can be used to perform initial real-time screening with high throughput based on morphological features to identify suspicious targets then CRS is guided to address the targets in real time and fully characterize their biochemical fingerprints for confirmation.

Disinfectant and Antimicrobial Susceptibility Studies of Staphylococcus aureus Strains and ST398-MRSA and ST5-MRSA Strains from Swine Mandibular Lymph Node Tissue, Commercial Pork Sausage Meat and Swine Feces.

Staphylococcus aureus (S. aureus) causes gastrointestinal illness worldwide. Disinfectants are used throughout the food chain for pathogenic bacteria control. We investigated S. aureus bioavailability in swine Mandibular lymph node tissue (MLT) and pork sausage meat (PSM), established susceptibility values for S. aureus to disinfectants, and determined the multilocus sequence type of MRSA strains. Antimicrobial and disinfectant susceptibility profiles were determined for 164 S. aureus strains isolated from swine feces (n = 63), MLT (n = 49) and PSM (n = 52). No antimicrobial resistance (AMR) was detected to daptomycin, nitrofurantoin, linezolid, and tigecycline, while high AMR prevalence was determined to erythromycin (50.6%), tylosin tartrate (42.7%), penicillin (72%), and tetracycline (68.9%). Methicillin-resistant S. aureus (MRSA) strains, ST398 (n = 6) and ST5 (n = 1), were found in the MLT and PSM, 4 MRSA in MLT and 3 MRSA strains in the PSM. About 17.5% of feces strains and 41.6% of MLT and PSM strains were resistant to chlorhexidine. All strains were susceptible to triclosan and benzalkonium chloride, with no cross-resistance between antimicrobials and disinfectants. Six MRSA strains had elevated susceptibilities to 18 disinfectants. The use of formaldehyde and tris(hydroxylmethyl)nitromethane in DC&R was not effective, which can add chemicals to the environment. Didecyldimethylammonium chloride and benzyldimethylhexadecylammonium chloride were equally effective disinfectants. ST398 and ST5 MRSA strains had elevated susceptibilities to 75% of the disinfectants tested. This study establishes susceptibility values for S. aureus strains from swine feces, mandibular lymph node tissue, and commercial pork sausage against 24 disinfectants. Since it was demonstrated that S. aureus and MRSA strains can be found deep within swine lymph node tissue, it may be beneficial for the consumer if raw swine lymph node tissue is not used in uncooked food products and pork sausage.

Characteristics and optimal ablation settings of a novel, contact-force sensingand local impedance-enabled catheter in an ex vivo perfused swine ventricle model.

Local impedance (LI) has emerged as a new technology that informs on electrical catheter-tissue coupling during radiofrequency (RF) ablation. Recently, IntellaNav StablePoint, a novel LI-enabled catheter that equips contact force (CF) sensing, has been introduced. Although StablePoint and its predecessor IntellaNav MiFi OI share the common technology that reports LI, distinct mechanics for LI sensing between the two products raise a concern that the LI-RF lesion formation relationship may differ. In an ex vivo swine cardiac tissue model, we investigated the initial level and range of a reduction in LI during a 60-sRF ablation and the resultant lesion characteristics at nine combinations of three energy power (30, 40, and 50 W) and CF (10, 30, and 50 g) steps. Correlations and interactions between CF, LI, wattage, and formed lesions were analyzed. Incidence of achieving LI drop plateau and that of a steam pop were also determined. Positive correlations existed between CF and initial LI, CF and absolute/relative LI drop, CF and lesion volume, and LI drop and lesion volume. At the same LI drop, wattage-dependent gain in lesion volume was observed. Steam pops occurred in all CF steps and the prevalence was highest at 50 W. LI drop predicted a steam pop with a cutoff value at 89Ω. In StablePoint, wattage crucially affects LI drop and lesion volume. Because 30 W ablation may by underpowered for intramural lesion formation and 50 W often resulted in a steam pop, 40 W appears to achieve the balance between the safety and efficacy.

Emergence and adaptive evolution of influenza D virus

As a novel member of the Orthomyxoviridae, influenza D virus (IDV) was firstly isolated from swine. However, cattle were found to serve as its primary reservoir. The study of IDV emergence can shed light into the dynamics of zoonotic infections and interspecies transmission. Although there is an increasing number of strains and sequenced IDV strains, their origin, epidemiology and evolutionary dynamics remain unclear. In this study, we reconstruct the diversity and evolutionary dynamics of IDVs. Molecular detection of swine tissue samples shows that six IDV positive samples were identified in the Eastern China. Phylogenetic analyses suggest three major IDV lineages designated as D/Japan, D/OK and D/660 as well as intermediate lineages. IDVs show strong association with geographical location indicating a high level of local transmission, which suggests IDVs tend to establish a local lineage of in situ evolution. In addition, the D/OK lineage widely circulates in swine in Eastern China, and all of the Chinese virus isolates form a distinct sub-clade (D/China sub-lineage). Furthermore, we identified important amino acids in the HEF gene under positive selection that might affect its receptor binding cavity relevant for its broader cell tropism. The combined results highlight that more attention should be paid to the potential threat of IDV to livestock and farming in China.

Evaluation of an automated insulated isothermal polymerase chain reaction system for rapid and reliable, on-site detection of African swine fever virus.

To evaluate the utility of an automated insulated isothermal PCR (iiPCR) system for rapid and reliable on-site detection of African swine fever virus (ASFV) in swine biological samples. Lymph node, tissue homogenate, whole blood, serum, spleen, and tonsil samples collected from swine in North and South Vietnam. Analytic sensitivity of the iiPCR system was determined by serial dilution and analysis of 2 samples (swine tissue homogenate and blood) predetermined to be positive for ASFV. Analytic specificity was assessed by analysis of 2 samples predetermined to be negative for ASFV and positive or negative for other swine pathogens (classical swine fever virus, porcine reproductive and respiratory syndrome virus, foot-and-mouth disease virus, and porcine circovirus type 2). Diagnostic performance of the iiPCR system for detection of ASFV was determined by analysis of the various tissue sample types. For all tests, a real-time PCR assay was used as the reference method. The iiPCR system was able to detect ASFV in swine blood or tissue homogenate at dilutions up to 106, whereas the real-time PCR assay was able to detect dilutions of up to 105 or 106. The iiPCR system had high analytic specificity for detection of ASFV versus other swine pathogens. Between 97% and 100% agreement was found between results of the iiPCR system for the various tissue samples and results of real-time PCR assay. The evaluated iiPCR system was found to be a rapid, reliable, and sample-flexible method for ASFV detection and may be useful for disease surveillance and quarantine in national strategies for early ASF control.

Determination of macrolides in animal tissues and egg by multi-walled carbon nanotube-based dispersive solid-phase extraction and ultra-high performance liquid chromatography–tandem mass spectrometry

A simple and reliable analytical method was developed for the simultaneous determination of 11 macrolides in swine, chicken, bovine, and sheep tissues (muscle, liver, kidney, and fat), as well as eggs. Samples were extracted using a mixture of acetonitrile, ethyl acetate, and methanol; dispersive solid-phase extraction purification was then performed using multi-walled carbon nanotubes as the sorbent. The analytes were separated through ultra-high performance liquid chromatography and detected by electrospray ionization on a triple quadrupole mass spectrometer. The average recoveries ranged from 83.5% to 111.4%; the corresponding intra-day and inter-day relative standard deviations were less than 13.6% and 16.4%, respectively. The limit of detection and quantification of the eggs were 0.1–0.6 and 2.0 μg/kg, respectively. For other tissues, the limits of detection and quantification were 0.1–2.0 μg/kg and 5.0 μg/kg, respectively. The proposed method was successfully employed for the analysis of real samples to demonstrate its applicability.

Selenium deficiency causes apoptosis through endoplasmic reticulum stress in swine small intestine.

Selenium (Se) plays a crucial role in intestinal health. However, the specific mechanism by which deficiency of Se causes intestinal damage remains unclear. This study was to explore whether Se deficiency can cause ER stress and induce apoptosis in swine small intestine. We established the Se deficiency swine model in vivo and the intestinal epithelial (IPEC-J2) cell Se deficiency model in vitro. The results of morphological observation showed that Se deficiency caused structural damage in intestinal villi and the decrease of goblet cell structure. The apoptotic characteristics such as nucleolar condensation, mitochondrial swelling, and apoptotic bodies were observed in the IPEC-J2 cells. The results of acridine orange/ethidium bromide and mitochondrial membrane potential fluorescence staining in vitro showed that there were more apoptotic cells in the Se-deficiency group than that in the control group. The protein and/or mRNA expression levels of Bax, Bcl-2, caspase 3, caspase 8, caspase 9, cytc, PERK, ATF6, IRE, XBP1, CHOP, GRP78, which are related to ER stress-apoptosis pathway, were significantly increased in the Se-deficient group which compared with the control group in vivo and in vitro were consistent. These results indicated that Se deficiency induced ER stress and increased the apoptosis in swine small intestine and IPEC-J2 cells and then caused the damage in swine small intestinal tissue. Besides, the results of gene expressions in our experiment proved that ER stress induced by Se deficiency promoted apoptosis. These results filled the blank in the mechanism of Se deficiency-induced intestinal injury in swine.