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A new Lateral Force Impact Tribometer (LFIT) is designed to quantify the dynamic friction of synthetic seat belt and D Ring Polymer (DRP) under transient conditions during the initial sliding period. LFIT simulates the sliding between two bodies subjected to a sudden lateral force applied, resulting in relative motion. Transient friction under suddenly applied initial acceleration conditions is obtained from the displacement response. LFIT overcomes stiffness concerns of most displacement-controlled tribometers in which the sensors and actuators influence the contact stiffness, nature of asperity interaction, and frictional characteristics. The displacement vs. time response showed the variation in displacement during the initial 0.3 mm sliding distance. LFIT is modelled as a spring-mass-Coulomb damper system applied for transient analysis. The effect of contact pressure on the transient Coefficient of Friction (CoF) is studied in the present work. This paper perhaps presents the first report that enables the capture of the friction transition within 10 ms from the start of sliding. [ABSTRACT FROM AUTHOR]

Intraoperative ultrasound is a promising tool for intraoperative tumor resection control. Navigated three-dimensional US (n3DUS) has many benefits over standard two-dimensional US (2DUS). Two cohorts (2DUS and n3DUS) of patients with histologically confirmed adult diffuse gliomas undergoing US-guided resection control were compared. The primary outcomes assessed were extent of resection and morbidity. Multivariate analysis was performed to account for tumor characteristics (delineation and eloquence) and surgeon experience, which could confound the results. n3DUS was used more often (n = 252) than 2DUS (n = 86). Tumor delineation was similar in 2DUS and n3DUS cohorts, although the n3DUS cohort included more nonenhancing, histologically lower grade (2–3) gliomas and had more gliomas located in eloquent regions; also, n3DUS was more often used by senior surgeons. Gross total resection (GTR) rates were 47%, and major morbidity was 9.5%. On multivariate analysis, after controlling for all other variables between the 2 groups, patients with well-delineated tumors, patients with prior treatment, and patients who underwent n3DUS were more likely to have GTR (adjusted odds ratios 3.0, 1.8, and 2.2, respectively), whereas patients with tumors in eloquent locations were half as likely (adjusted odds ratio 0.5) to have GTR. Eloquent located tumors were likely to be associated with higher neurological morbidity, although major morbidity was not significantly different. Good delineation, noneloquent location, and use of n3DUS was associated with a higher probability of GTR in glioma surgery. Surgeons' experience did not influence the extent of resection. Morbidity was predominantly associated with eloquent location, independent of all other factors. [ABSTRACT FROM AUTHOR]

Recombinant envelope protein-1 (E1) and E2 of Chikungunya virus (CHIKV) has been shown to elicit neutralizing antibodies and a balanced Th1/Th2 response in mice however with limited protection. Recently reported CHIK virus-like particles showed augmented immunity and protection in adult mice in comparison to E1 and E2, however exacerbated the disease in aged subjects. In order to improve the overall efficacy of protein based vaccines, novel strategies need to be adopted. The discovery of IgM Fc receptor (FcμR) and its role in humoral immune response led us to hypothesise that fusion of an antigen with Fc of IgM may enhance its immunogenicity by polymerizing it and FcμR mediated activation of B and other immune cells. We report in the current study, expression of E2 subunit of CHIKV in fusion with various IgM Fc domains/peptides in E. coli , their in-vitro refolding, characterization and immune response in C57BL/6 mice. Candidates fused with CH3-CH4 Fc fragment produced stable oligomers, whereas the one fused with peptides remained monomeric. The latter elicited a strong humoral and a balanced Th1/Th2 response in mice, whereas the polymeric candidate despite eliciting a strong humoral response, stimulated a biased Th1 response and exhibited higher virus neutralization in Vero cells. [ABSTRACT FROM AUTHOR]

Background Subcortical motor mapping is crucial to ensure preservation of motor tracts during resections of tumors. Continuous dynamic mapping using a modified monopolar suction probe is a novel and effective way of achieving this goal. We describe our experience using this technique. Methods Forty patients were operated on between June 2017 and February 2018. Transcranial electric stimulation (TES) and direct cortical strip (DCS) motor evoked potentials (MEPs) were monitored. Subcortical stimulation (SCS) mapping was attempted in all cases by adapting the technique using a monopolar suction stimulator. Neurologic outcomes and extent of resection were analyzed. Results Motor fibers were between 0 and 7.6 mm away from the tumor boundaries in 26 patients. TES MEP were monitored in all patients. DCS MEPs were attempted in 31 and successfully monitored in 26 patients. SCS using the monopolar suction probe worked in all patients except one. SCS elicited no responses at 15-mA motor thresholds in 16 patients. The motor threshold ranged from 3 to 10 mA in the remainder. Overall, MEP changes were noted in 5 patients. Ten patients experienced neurologic worsening (6 transient, 3 prolonged, and 1 delayed). There was no permanent deficit at 3 months. DCS MEPs predicted neurologic worsening better than did TES MEPs. Radical resections were achieved in 68%. Neuromonitoring inputs resulted in premature termination of resection in 14 patients (35%). Radical resections (near-total resections) were still achieved in 8 of the 14 patients. Conclusions Continuous dynamic subcortical mapping is a reliable method to map the motor tracts. This process is crucial to correctly identify truly eloquent tumors and tailor the surgical procedure as per planned goals, maximizing the resections with acceptable morbidity. Highlights • White matter tract integrity is crucial in ensuring optimal neurological outcomes after surgery for eloquent region tumors. • Corticospinal tract fibers can be mapped with reliable estimate of distance to the fibers using monopolar train technique. • Dynamic and continuous subcortical mapping using a monopolar suction device optimizes temporal and geographical coverage. • We were able to successfully adapt this technique to our setup during routine resection of motor-eloquent tumors. • Combined with MEP monitoring it facilitated radical resections in 70% cases with no long term neurological morbidity. [ABSTRACT FROM AUTHOR]

The present study was aimed at generating a reassortant vaccine candidate virus with clade 2.3.2.1 Hemagglutinin (HA) and its evaluation in a challenge study for protection against homologous (2.3.2.1 clade) and heterologous (2.2 clade) highly pathogenic avian influenza (HPAI) H5N1 viruses. Plasmid-based reverse genetics technique was used to rescue a 5 + 3 reassortant H5N2 strain containing the modified HA of H5N1 (clade 2.3.2.1), the Neuraminidase (NA) of H9N2, the Matrix (M) of H5N1 and the internal genes of A/WSN/33 H1N1. In addition, another 6 + 2 reassortant virus containing modified HA from H5N1 (clade 2.3.2.1), the NA from H9N2 and the internal genes of A/WSN/33 H1N1 was also rescued. The 5 + 3 reassortant H5N2 virus could grow to a higher titer in both MDCK cells and chicken eggs compared to the 6 + 2 reassortant H5N2 virus. The vaccine containing the inactivated 5 + 3 reassortant H5N2 virus was used in a two-dose immunization regime which protected specific pathogen free (SPF) chickens against two repeated challenges with homologous 2.3.2.1 clade and heterologous 2.2 clade HPAI H5N1 viruses. The 5 + 3 reassortant H5N2 virus based on clade 2.3.2.1 generated in this study can be effective in protecting chickens in the case of an outbreak caused by antigenically different clade 2.2 HPAI H5N1 viruses and opens the way to explore its applicability as potential vaccine candidate especially in the Asian countries reporting these clades frequently. The study also indicates that sequential immunization can broaden protection level against antigenically diverse strains of H5N1 viruses. [ABSTRACT FROM AUTHOR]