Under nonlinear prey-harvesting, effect of strong Allee effect on the dynamics of a modified Leslie-Gower predator-prey model.

In the present study, the effects of the strong Allee effect on the dynamics of the modified Leslie-Gower predator-prey model, in the presence of nonlinear prey-harvesting, have been investigated. In our findings, it is seen that the behaviors of the described mathematical model are positive and bounded for all future times. The conditions for the local stability and existence for various distinct equilibrium points have been determined. The present research concludes that system dynamics are vulnerable to initial conditions. In addition, the presence of several types of bifurcations (e.g., saddle-node bifurcation, Hopf bifurcation, Bogdanov-Takens bifurcation, homoclinic bifurcation) has been investigated. The first Lyapunov coefficient has been evaluated to study the stability of the limit cycle that results from Hopf bifurcation. The presence of a homoclinic loop has been demonstrated by numerical simulation. Finally, possible phase drawings and parametric figures have been depicted to validate the outcomes.

Impact of Meconium-Stained Amniotic Fluid on Neonatal Outcome in a Tertiary Hospital.

Objective The aim of this study was to determine the perinatal outcome of pregnant patients complicated with meconium-stained amniotic fluid (MSAF) compared with clear amniotic fluid. Methodology This prospective cross-sectional study was conducted in the Department of Obstetrics and Gynecology in collaboration with the Department of Pediatrics at Indira Gandhi Institute of Medical Sciences, Patna, India, from September 2016 to January 2018. A total of 200 patients were included in the study after taking their written consent. Out of these 200 patients, 100 patients had MSAF, and the other 100 patients with clear liquor were taken as controls after fulfilling the inclusion and exclusion criteria. These two groups of patients were compared regarding various maternal and neonatal parameters. These parameters were compared and tested statistically for significance. Results Among the 100 patients with MSAF, 20 patients had grade 1 meconium (X), 22 patients had grade 2 meconium (Y), and 58 patients had grade 3 meconium (Z). The majority of patients in the MSAF group were primigravida and more than 25 years of age. In addition, 47% of patients in the MSAF group had some associated high-risk factors and 50% of patients had non-reassuring fetal heart rate patterns, and among these, 39 patients had grade 3 MSAF (X). In the MSAF group, 49% of patients had undergone lower segment cesarean section (LSCS), whereas in the non-MSAF group, it was 37%. Also, 30% of babies in the MSAF group and 13% in the non-MSAF group had neonatal intensive care unit (NICU) admission; 22% of babies in the MSAF group and 12% of babies in the non-MSAF group had an adverse neonatal outcome. Meconium aspiration syndrome was present in 14% of the patients in the MSAF group, and among these, two babies had neonatal death and both had severe birth asphyxia. In the non-MSAF group, there was one neonatal death due to neonatal sepsis. However, after statistically analyzing the neonatal outcome in both the groups, there was no statistical difference between the two groups (p<0.001). Conclusion MSAF is associated with increased frequency of operative delivery, poor neonatal outcomes, and increased NICU admission. Management of labor with MSAF requires appropriate intrapartum care with continuous fetal heart rate monitoring, and this can reduce unnecessary cesarean sections in patients with MSAF.

Phase III HIV vaccine trial in Thailand: a step toward a protective vaccine for HIV.

The large human efficacy trail in Thailand, RV144, was concluded in the summer of 2009. This is the first Phase III trial to show limited, but significant, efficacy in preventing HIV acquisition. This trial represents the first sign that a preventive vaccine for HIV may be feasible. The vaccine regimen tested in Thailand consisted of priming with a Canarypox vector carrying three synthetic HIV genes. The priming was followed by booster inoculations with two recombinant envelope proteins from HIV, clade B and E. The need to understand the role in protection from HIV acquisition of the new responses, induced by this vaccine combination, has brought together many researchers with the common goal of improving the development of a safe and effective vaccine for HIV.

Induction of SIV p27-specific multifunctional T cells in the gut following prime-boost immunization with Clostridium perfringens and adenovirus vaccines expressing SIV p27.

A vaccine-induced cellular immune response to simian immunodeficiency virus (SIV) in the gut mucosal tissue may prevent the establishment or severity of new SIV infection. An oral Clostridium perfringens expressing SIV p27 (Cp-p27) vaccine that delivers SIV p27 to the gut was evaluated for its ability to prime multifunctional cellular immunity in the gut mucosa. Gut Peyer's patches dendritic cells matured in response to in vitro exposure to Cp-p27 and stimulated production of p27-specific IFN-gamma. In mice, the oral vaccination with the Cp-p27 vaccine and systemic immunization with adenovirus expressing SIV p27 (Ad-p27) induced robust systemic and mucosal immune responses. Furthermore, the prime-boost regimen induced p27-specific multifunctional CD8+ T cells in the gut. These results indicate that priming gut tissue with Cp-p27 can enhance the gut mucosal cellular immune response generated via systemic immunization with Ad-p27.

The biology of oral tolerance and issues related to oral vaccine design.

Intestinal tissues are continuously exposed to tremendous amount of foreign material, either beneficial or harmful. Although strong protective immune responses are required to clear harmful pathogen infections, similar responses against food antigen can lead to harmful inflammation. Therefore, oral tolerance or unresponsiveness against dietary and commensal bacteria is also important to maintain tissue integrity by preventing harmful inflammatory responses in the intestine. While oral tolerance is an important phenomenon to protect unnecessary inflammatory responses, it presents an obstacle in the development of oral vaccines. Therefore an understanding of the gut immune system and the induction of oral tolerance is important. This review will focus on important aspects of the intestinal immune system and how immune responses in the intestine maintain homeostasis via oral tolerance. Also it will provide new insights in the development of oral vaccines.