Vimentin affects inflammation and neutrophil recruitment in airway epithelium during Streptococcus suis serotype 2 infection.

Streptococcus suis serotype 2 (SS2) frequently colonizes the swine upper respiratory tract and can cause Streptococcal disease in swine with clinical manifestations of pneumonia, meningitis, and septicemia. Previously, we have shown that vimentin, a kind of intermediate filament protein, is involved in the penetration of SS2 through the tracheal epithelial barrier. The initiation of invasive disease is closely related to SS2-induced excessive local inflammation; however, the role of vimentin in airway epithelial inflammation remains unclear. Here, we show that vimentin deficient mice exhibit attenuated lung injury, diminished production of proinflammatory cytokines interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and the IL-8 homolog, keratinocyte-derived chemokine (KC), and substantially reduced neutrophils in the lungs following intranasal infection with SS2. We also found that swine tracheal epithelial cells (STEC) without vimentin show decreased transcription of IL-6, TNF-α, and IL-8. SS2 infection caused reassembly of vimentin in STEC, and pharmacological disruption of vimentin filaments prevented the transcription of those proinflammatory cytokines. Furthermore, deficiency of vimentin failed to increase the transcription of nucleotide oligomerization domain protein 2 (NOD2), which is known to interact with vimentin, and the phosphorylation of NF-κB protein p65. This study provides insights into how vimentin promotes excessive airway inflammation, thereby exacerbating airway injury and SS2-induced systemic infection.

Coinfection with porcine circovirus type 2 and Glaesserella parasuis serotype 4 enhances pathogenicity in piglets.

Coinfection of Porcine circovirus type 2 (PCV2) and Glaesserella parasuis type 4 (GPS4) is widespread clinically, resulting in high morbidity and mortality, however, interactions between the two pathogens during coinfection and the coinfection pathogenesis are poorly understood. In this study, a piglet model coinfected with PCV2 and GPS4 was established; coinfection of the piglets' group showed more obvious symptoms, such as high fever and emaciation, and more severe histological lesions appeared in various organs. Importantly, piglets in the coinfection group produced lower levels of PCV2 and GPS4 antibodies, and showed high levels of inflammatory cytokines, TLR2, and TLR4, while the levels of CD4, CD8, MHC II, costimulatory molecules, and IL-12p40 were decreased. In addition, a model of macrophage 3D4/21 cells coinfection with PCV2 and GPS4 was established, coinfected cells exhibited increased expression of the cytokines IL-6, IL-8, TNF-α, IL-1ß, and the receptors TLR2, TLR4, while decreased MHC II. We further demonstrate that cytokine production is associated with the activation of NF-κB and NLRP3 inflammasome signaling pathways, and TLR4 is also involved. Altogether, our findings suggest that coinfection with PCV2 and GPS4 exacerbates the inflammatory response, resulting in severe tissue damage, and probably impaired macrophage antigen presentation and T cell activation, resulting in immune dysregulation, aggravating host infection.

Impact of Short-Term Heart Rate Variability in Patients with STEMI Treated by Delayed versus Immediate Stent in Primary Percutaneous Coronary Intervention: A Prospective Cohort Study.

Objective: Patients with ST-segment elevated myocardial infarction (STEMI) have been treated with the delayed stent strategy to reduce the occurrence of postoperative no-reflow and improve the recovery of postoperative cardiac function. However, the effects of electrocardiac activity and autonomic nerve function after primary percutaneous coronary intervention (pPCI) have been rarely reported. The purpose of this study was to investigate the effects of short-term heart rate variability (HRV) in patients with STEMI treated by immediate stent (IS) and delayed stent (DS) strategy. Methods: A total of 178 patients with STEMI were divided into 124 cases (69.66%) in the IS group and 54 cases (30.34%) in the DS group from July 2019 to September 2021. The mean heart rate, premature ventricular contraction (PVC), left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter (LVED), and HRV indexes were compared between the two groups. Results: In terms of cardiac electrical stability, the number of PVCs, the percentage of PVCs, and the number of paired PVCs in the DS group were lower than those in the IS group. In terms of HRV, high frequency (HF) and standard deviation of all NN (SDNN) intervals were higher in the patients with DS strategy than IS strategy. There were no significant differences in the LVED and LVEF between the two groups. Conclusion: Compared to the IS strategy, the DS strategy in pPCI in patients with STEMI has advantages in postoperative cardiac electrical stability and short-term cardiac autonomic nerve function, with no difference in postoperative short-term cardiac function.

[Adaptive removal of motion artifact from ECG based on impedance detection].

Motion artifact is a significant source of noise in ambulatory physiologic signals and can affect the diagnoses seriously. To cope with this problem, we adopted certain methods for removing motion artifact from ECG signals via synchronous acquisition of the elector/skin impedance as the reference signal of adaptive filter. The results demonstrated that 3rd order RLS adaptive filter can remove the baseline shift effectively with an exciting current of 120 Hz and 50 microA. Such system was implemented to investigate the utility of ambulatory heart rate monitoring, which provides convenient and reliable monitoring services for patients.

A wearable respiration monitoring system based on digital respiratory inductive plethysmography.

In this paper we present a wearable device for continuous monitoring of respiration signal and the associated algorithm for signal evaluations. The device took advantages of a proven respiratory inductive plethysmograph (RIP) technology and a wireless body sensor networks (BSN) development platform. The textile RIP sensor was integrated into a suit that could be comfortably worn around thorax or abdomen for monitoring respiration during sleep. A smart signal processing algorithm was implemented for extracting the dynamic respiration rate. The results of in-situ experiments from ten healthy subjects suggested that our system worked as intended. Due to the high reliability and low cost of our system it is believed to meet the future demands on home-based monitoring and diagnosis of sleep disorder-related diseases.

A low-complexity medium access control framework for body sensor networks.

This paper proposed a low-complexity medium access control (MAC) protocol tailored for body sensor networks (BSN) applications. The MAC protocol was designated to handle collision avoidance by reducing the numbers of the overhead packets for handshake control within the BSN. We also suggested a novel message recovery mechanism for getting back the lost physiological information. The adaptive synchronization scheme we have implemented exploited the features of multiple data-rate and adjustable precision design to support differentiated healthcare applications. The MAC protocol was fully implemented using our BSN development platform. The experimental results suggested the improved MAC design was compact and energy-efficient.

[The formation of BPDE-DNA adduct in rat and its determination by high performance liquid chromatography].

OBJECTIVE: To study the benzo (a) pyrene (BaP) induced DNA adduct in rat and establish a method to measure the DNA adduct in blood by high performance liquid chromatography (HPLC). METHODS: The SD rats were treated with 100 mg/kg of BaP-DMSO (cosolvent: 1% sodium carboxymethyl cellulose) once by i.p., and the blood of femoral vein was collected 5 hours later. The blood DNA was extracted by kit and confirmed by agarose gel electrophoresis. After extraction, the DNA adducts were hydrolyzed in 0.1 nmol/L HCl at 90 degrees C for 4 hours. The acid-hydrolysis products (BP-tetrols) of DNA adducts were extracted by ethyl acetate and measured by HPLC, and finally confirmed by HPLC-MS. RESULTS: In chromatogram there were new peaks to occur for rats treated by BaP, with compared to control. By HPLC-MS, one of the new peaks was confirmed to be BP-tetrol. CONCLUSION: The rats ingesting BaP in the way described in this experiment can form DNA adducts, and the adducts in blood can be detected by HPLC.