Differential expression analysis of the broiler tracheal proteins responsible for the immune response and muscle contraction induced by high concentration of ammonia using iTRAQ-coupled 2D LC-MS/MS

Ammonia has been considered the contaminant primarily responsible for respiratory disease in poultry. Even though it can cause tracheal lesions, its adverse effects on the trachea have not been sufficiently studied. The present study investigated tracheal changes in Arbor Acres broilers(Gallus gallus) induced by high concentration of ammonia using isobaric tag for relative and absolute quantification(iTRAQ)-based proteome analysis. In total, 3,706 proteins within false discovery rate of 1% were identified, including 119 significantly differentially expressed proteins. Functional analysis revealed that proteins related to immune response and muscle contraction were significantly enriched. With respect to the immune response, up-regulated proteins(like FGA) were pro-inflammatory, while down-regulated proteins participated in antigen processing and antigen presenting(like MYO1G), immunoglobulin and cathelicidin production(like fowlicidin-2), and immunodeficiency(like PTPRC). Regarding muscle contraction, all differentially expressed proteins(like TPM1) were up-regulated. An over-expression of mucin, which is a common feature of airway disease, was also observed. Additionally, the transcriptional alterations of 6 selected proteins were analyzed by quantitative RT-PCR. Overall, proteomic changes suggested the onset of airway obstruction and diminished host defense in trachea after ammonia exposure. These results may serve as a valuable reference for future interventions against ammonia toxicity.

Chronic heat stress induces the disorder of gut transport and immune function associated with endoplasmic reticulum stress in growing pigs

Although high temperatures influence gut health,data on underlying mechanisms remains scant.Using a pig model,this study performed a global analysis on how chronic heat stress affects the transport and immune function of the gut through transcriptome,proteome,microbial diversity and flow cytometry.A total of 27 pigs with similar body weights were assigned into 3 groups,control(Con)group(23℃),chronic heat stressed(HS)group(33°C),and pair-fed(PF)group,in a controlled environment for 21 days.Our results showed that pigs in the HS group had reduced growth performance and diminished height of ileal villi(P<0.01).Transcriptome and proteome analyses demonstrated notable modification of expression of nutrients and ion transport-related transporters and gut mechanical barrier-related genes by chronic heart stress(P<0.05),suggesting damage of transport functions and the gut barrier.Chronic heat stress-induced endoplasmic reticulum stress also increased the synthesis of misfolded proteins,leading to upregulation of misfolded protein degradation and synthesis,as well as vesicle transport disorder(P<0.05).Energy supply processes were enhanced in the mitochondrion(P<0.05)to maintain biological processes with high energy demands.Furthermore,chronic heat stress activated complement cascade response-related genes and proteins in the gut mucosa(P<0.05).Our flow cytometry assays showed that the proportion of gut lymphocytes(CD4^(+)T cells,T cells,B cells in Peyer’s patch lymphocytes and CD4^(+)CD25^(+)T cells in intraepithelial lymphocytes)were significantly altered in the HS group pigs(P<0.05).In addition,the occurrence of gut microbial dysbiosis in the HS group pigs was characterized by increased potential pathogens(e.g.,Asteroleplasma,Shuttleworthia,Mycoplasma)and suppression of beneficial bacteria(e.g.,Coprococcus and Aeriscardovia),which are associated with gut immune function.Altogether,our data demonstrated that chronic heat stress induced gut transport and immune function disorder associated with endoplasmic reticulum stress in growing pigs.

3D printing interface-modified PDMS/MXene nanocomposites for stretchable conductors

Additive manufacturing has rapidly evolved over recent years with the advent of polymer inks and those inks containing novel nanomaterials.The compatibility of polymer inks with nanomaterial inks remains a great challenge.Simple yet effective methods for interface improvement are highly sought-after to significantly enhance the functional and mechanical properties of printed polymer nanocomposites.In this study,we developed and modified a Ti_(3)C_(2) MXene ink with a siloxane surfactant to provide compatibility with a polydimethylsiloxane(PDMS)matrix.The rheology of all the inks was investigated with parameters such as complex modulus and viscosity,confirming a self-supporting ink behaviour,whilst Fourier transform infrared spectroscopy exposed the inks’reaction mechanisms.The modified MXene nanosheets have displayed strong interactions with PDMS over a wide strain amplitude.An electrical conductivity of 6.14×10^(−2) S cm^(−1) was recorded for a stretchable nanocomposite conductor containing the modified MXene ink.The nanocomposite revealed a nearly linear stress-strain relationship and a maximum stress of 0.25 MPa.Within 5%strain,the relative resistance change remained below 35%for up to 100 cycles,suggesting high flexibility,conductivity and mechanical resilience.This study creates a pathway for 3D printing conductive polymer/nanomaterial inks for multifunctional applications such as stretchable electronics and sensors.