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In ecological systems, the predator-induced fear dampens the prey's birth rate; yet, it fails to extinguish their population, as they endure and survive even under significant fear-induced costs. In this study, we unveil a modified Leslie-Gower predator-prey model by incorporating the fear of predators, cooperative hunting, and predator-taxis sensitivity. We embark upon an exploration of the positivity and boundedness of solutions, unearthing ecologically viable equilibrium points and their stability conditions governed by the model parameters. Delving deeper, we unravel the scenario of transcritical, saddle-node, Hopf, Bogdanov-Takens, and generalized-Hopf bifurcations within the system's intricate dynamics. Additionally, we observe the bistable nature of the system under some parametric conditions. Further, the nonautonomous extension of our model introduces the intriguing interplay of seasonality in some crucial parameters. We establish a set of sufficient conditions that guarantee the permanence of the seasonally driven system. By conducting a numerical study on the seasonally forced model, we observe a myriad of phenomena manifesting the predator-prey dynamics. Notably, periodic solutions, higher periodic solutions, and bursting patterns emerge, alongside intriguing chaotic dynamics. Specifically, seasonal variations of the predator-taxis sensitivity and hunting cooperation can lead to the extinction of prey species and even the control of chaotic (higher periodic) solutions through the generation of a simple periodic solution. Remarkably, the seasonal forcing has the capacity to govern the chaotic behavior, leading to an exceptionally quasi-periodic arrangement in both prey and predator populations.
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In this investigation, we construct a predator-prey model that distinguishes between immature and mature prey, highlighting group defense strategies within the mature prey. First, we embark on exploring the positivity and boundedness of the solution, unraveling sustainable equilibrium points, and deducing their stability conditions. Upon further investigation, we observe that the system exhibits diverse bifurcations, including Hopf, saddle-node, transcritical, generalized Hopf, cusp, and Bogdanov-Takens bifurcations. The results reveal that heightened fear decreases mature prey density, potentially causing prey extinction beyond a certain threshold. Increased maturation rates lead to the coexistence of immature and mature prey populations and higher predator density. Stronger group defense boosts mature prey density, while weaker defense results in weak persistence. Lower values of the maturation rate of prey and the decline rate of predators sustain only the predator population, reliant on resources other than focal prey. Furthermore, our model demonstrates intriguing and diverse dynamical phenomena, including various forms of bistability across distinct bi-parameter planes. We also explore the dynamics of a related nonautonomous system, where certain parameters are considered to vary with time. In the seasonally forced model, we set out to define criteria regarding the existence and stability of positive periodic solutions. Numerical investigations into the seasonally forced model uncover a spectrum of dynamics, ranging from simple periodic solutions to higher periodicities, bursting patterns, and chaotic behavior.
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Miedo , Modelos Biológicos , Conducta Predatoria , Animales , Conducta Predatoria/fisiología , Miedo/fisiología , Dinámica Poblacional , Cadena Alimentaria , Simulación por ComputadorRESUMEN
INTRODUCTION: With the increasing use of traditional medicine, there is a need to be vigilant in identifying and reporting adverse reactions associated with them. Punarnava Mandura is a commonly used Ayurvedic medicine for the treatment of anemia. It is well tolerated by the patients. To our knowledge, allergic reactions to Punarnava Mandura have not been reported in the literature. We reported a case of adverse cutaneous reaction, which was probably associated with Purnarnava Mandura. CASE PRESENTATION: A 60-year-old female patient developed skin rashes over her neck region after taking Punarnava Mandura and other drugs for osteoarthritis. She recovered upon withdrawal of all the medicines and treatment with anti-allergic drugs. The patient re-initiated treatment for joint pain except for Punarnava Mandura and completed the course without a recurrence of the event making the Punarnava Mandura the culprit drug. CONCLUSION: Punarnava Mandura may cause allergic reactions, and clinicians should keep such adverse reactions in mind when using traditional medicine and report them to increase the scientific literature in this area.
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BACKGROUND: Food-borne pathogen Listeria monocytogenes is abundantly present in nature and accountable for sporadic and epidemic cases of listeriosis in humans. The objective of this study was to screen common food sources for L. monocytogenes using biochemical and molecular methods to detect and characterise its toxin genes as well as for biofilm formation. METHODS: A total of 92 samples, comprising dairy and street food products, were randomly collected from various sources for this investigation. The collected samples were processed for biochemical and molecular methods to detect L. monocytogenes. Additionally, virulence factors associated genes, antibiogram profiles and biofilm formation related assays were determined. RESULTS: L. monocytogenes presence was confirmed using molecular detection methods targeting prs and lmo1030 genes, along with MALDI-TOF MS. Following 16 S rRNA sequencing, the identified Listeria species were further categorised into two groups. L. monocytogenes was detected in two (2.17%) food samples tested (L-23 and L-74). Multiplex PCR indicated the presence of seven virulence-related genes in L. monocytogenes isolates, i.e., inlA, inlB, prfA, iap, actA, plcB, and hlyA. In addition, 17 antibiotics were tested, whereby two isolates showed resistance to clindamycin and azithromycin, while one isolate (L-74) was also resistant to nalidixic acid, co-trimoxazole, ampicillin, norfloxacin, and cefotaxime. L-23 and L-74 isolates showed biofilm formation, especially at pH 8.6 and 37°C. CONCLUSIONS: Besides the demonstration of the presence of L. monocytogenes in some dairy and street food products, this study underscores the need to increase the standards of hygiene on the one hand and the importance of the surveillance of food-borne pathogens on the other.
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Listeria monocytogenes , Listeriosis , Humanos , Listeria monocytogenes/genética , India , Antibacterianos/farmacología , Factores de Virulencia/genética , Microbiología de AlimentosRESUMEN
Bidens pilosa L. has been traditionally used as an anti-diabetic herbal medicine; however, its mechanism of action remains elusive. In this study, the potential role of B. pilosa compounds on alpha-amylase inhibition and regulation of multiple pathways was investigated via computational and experimental studies. The phytocompounds were retrieved from plant databases and published literature. The druggability profile of these compounds was predicted using MolSoft. The probable targets of these phytocompounds were predicted using BindingDB (similarity index ≥ 0.7). Further, compound-gene set-pathway and functional enrichment analysis were performed using STRING and KEGG pathway databases. The network between compound-protein-pathway was constructed using Cytoscape. Molecular docking was performed using AutoDock Vina, executed through the POAP pipeline. The stability of the best docked complex was subjected to all-atom molecular dynamics (MD) simulation for 100 ns to investigate their structural stabilities and intermolecular interactions using GROMACS software. Finally, B. pilosa hydroalcoholic extract was subjected to LC-MS and tested for dose- and time-dependent alpha-amylase inhibitory activity. Out of 31 bioactive compounds, 13 were predicted to modulate the human pancreatic alpha-amylase (AMY2A) and 12 pathways associated with diabetes mellitus. PI3K-Akt signaling pathway (hsa04151) scored the lowest false discovery rate by triggering 15 genes. Further intermolecular interaction analysis of the docked complex revealed that Brassidin had the highest active site interaction and lowest binding energy compared to standard acarbose, and MD reveals the formation of a stable complex throughout 100 ns production run. LC-MS analysis revealed the presence of 13 compounds (targeting AMY2A) in B. pilosa hydroalcoholic extract, which showed potent AMY2A inhibition by in vitro studies that corroborate in silico findings for its anti-diabetic activity. Based on these findings, enriched fractions/pure compounds inhibitory activity that can be performed in future for drug discovery. Supplementary Information: The online version contains supplementary material available at 10.1007/s40203-023-00187-9.
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BACKGROUND: Anemia is a worldwide problem with iron deficiency being the most common cause. When anemia occurs in pregnancy, it increases the risk of adverse maternal, fetal, and postnatal outcomes. It induces preterm births and low birth weight (LBW) deliveries, long-term neurodevelopmental sequelae, and an increased risk of earlier onset of postnatal iron deficiency. Anemia rates are among the highest in South Asia, and India's National Family Health Survey (NFHS-5) for 2019-2021 indicated that over half of pregnant women, and more than 65% of children, in the country are classified as anemic (Sciences IIfP, National Family Health Survey-5, 2019-21, India Fact Sheet). In 2021, the parent RAPIDIRON Trial (Derman et al., Trials 22:649, 2021) was initiated in two states in India, with the goal of assessing whether a dose of intravenous (IV) iron given to anemic women during early pregnancy results in a greater proportion of participants with normal hemoglobin concentrations in the third trimester and a lower proportion of participants with LBW deliveries compared to oral iron. As a follow-up to the RAPIDIRON Trial, the RAPIDIRON-KIDS Study will follow the offspring of previously randomized mothers to assess, neurobehavioral, hematological, and health outcomes. METHODS: This prospective observational cohort study will follow a subset of participants previously randomized as part of the RAPIDIRON Trial and their newborns. Study visits occur at birth, 6 weeks, 4 months, 12 months, 24 months, and 36 months and include blood sample collection with both maternal and infant participants and specific neurobehavioral assessments conducted with the infants (depending on the study visit). The primary outcomes of interest are (1) infant iron status as indicated by both hemoglobin and ferritin (a) at birth and (b) at 4 months of age and (2) the developmental quotient (DQ) for the cognitive domain of the Bayley Scales of Infant Development Version IV (BSID-IV) at 24 months of age. DISCUSSION: This RAPIDIRON-KIDS Study builds upon its parent RAPIDIRON Trial by following a subset of the previously randomized participants and their offspring through the first 3 years of life to assess neurodevelopmental and neurobehavioral (infants, children), hematological, and health outcomes. TRIAL REGISTRATION: ClinicalTrials.gov NCT05504863 , Registered on 17 August 2022. Clinical Trials Registry - India CTRI/2022/05/042933 . Registered on 31 May 2022.