Spatial dynamics of synergistic coinfection in rock-paper-scissors models.

We investigate the spatial dynamics of two-disease epidemics reaching a three-species cyclic model. Regardless of their species, all individuals are susceptible to being infected with two different pathogens, which spread through person-to-person contact. We consider that the simultaneous presence of multiple infections leads to a synergistic amplification in the probability of host mortality due to complications arising from any of the co-occurring diseases. Employing stochastic simulations, we explore the ramifications of this synergistic coinfection on spatial configurations that emerge from stochastic initial conditions. Under conditions of pronounced synergistic coinfection, we identify the emergence of zones inhabited solely by hosts affected by a singular pathogen. At the boundaries of spatial domains dominated by a single disease, interfaces of coinfected hosts appear. The dynamics of these interfaces are shaped by curvature-driven processes and display a scaling behavior reflective of the topological attributes of the underlying two-dimensional space. As the lethality linked to coinfection diminishes, the evolution of the interface network's spatial dynamics is influenced by fluctuations stemming from waves of coinfection that infiltrate territories predominantly occupied by a single disease. Our analysis extends to quantifying the implications of synergistic coinfection at both the individual and population levels Our outcomes show that organisms' infection risk is maximized if the coinfection increases the death due to disease by 30% and minimized as the network dynamics reach the scaling regime, with species populations being maximum. Our conclusions may help ecologists understand the dynamics of epidemics and their impact on the stability of ecosystems.

How local antipredator response unbalances the rock-paper-scissors model.

Antipredator behavior is a self-preservation strategy present in many biological systems, where individuals join the effort in a collective reaction to avoid being caught by an approaching predator. We study a nonhierarchical tritrophic system, whose predator-prey interactions are described by the rock-paper-scissors game rules. We perform a set of spatial stochastic simulations where organisms of one out of the species can resist predation in a collective strategy. The drop in predation capacity is local, which means that each predator faces a particular opposition depending on the prey group size surrounding it. Considering that the interference in a predator action depends on the prey's physical and cognitive ability, we explore the role of a conditioning factor that indicates the fraction of the species apt to perform the antipredator strategy. Because of the local unbalancing of the cyclic predator-prey interactions, departed spatial domains mainly occupied by a single species emerge. Unlike the rock-paper-scissors model with a weak species because of a nonlocal reason, our findings show that if the predation probability of one species is reduced because individuals face local antipredator response, the species does not predominate. Instead, the local unbalancing of the rock-paper-scissors model results in the prevalence of the weak species' prey. Finally, the outcomes show that local unevenness may jeopardize biodiversity, with the coexistence being more threatened for high mobility.

Caregiver oral health literacy: relationship with socioeconomic factors, oral health behaviors and perceived child dental status.

OBJECTIVE: To assess associations between caregiver oral health literacy (OHL) and socioeconomic factors, child and caregiver's oral health behaviors and perceptions of oral health status. BASIC RESEARCH DESIGN: Cross-sectional study. CLINICAL SETTING: University pediatric dentistry clinic. PARTICIPANTS: 205 pairs of caregivers and children aged 6 to 12-years undergoing dental treatment. METHOD: A questionnaire was sent to caregivers enquiring about socioeconomic factors, oral health behaviors, perceptions of own and child oral health. The clinical dental status of the children was recorded with the DMFT/dmft index. MAIN OUTCOME MEASURE: OHL was measured by the Brazilian version of the Rapid Estimate of Adult Literacy in Dentistry (BREALD-30). Descriptive analysis, unadjusted and adjusted logistic regression, odds ratio and confidence interval were calculated considering a significance level of 5%. RESULTS: The frequency of poor OHL was 21%. In adjusted analysis caregivers with 8 years or less of schooling had a 3.72 (95% CI 1.74-7.95) times greater chance of have poor OHL. Caregivers who perceived their child to have poor oral health were 2.70 (95% CI 1.10-6.63) times more likely to have poor OHL. CONCLUSIONS: Poor oral health literacy was more common among caregivers with less schooling and a poor perception of their child's oral health. OHL was unrelated to monthly family income, child dental health status, perception of own oral health or child or caregiver oral health behaviors.

Influence of gold nanoholes and nanoslits arrays on Raman spectra and optical reflectance of graphene oxide.

We report the effect of gold nanostructured substrates, fabricated by interference lithography technique (IL), on the Raman spectra and optical reflectance of graphene oxide (GO) layers. For purposes of comparison two gold nanostructured substrates, nanoslits (AuNSs) and circular nanoholes (AuNHs) were compared with a non-nanostructured gold substrate. Effects induced by the gold nanostructured substrates are discussed in terms of the ID/IG ratio and the FWHM of the G band (FWHM(G)) as a function of the G band intensity (IG), showing that both ID/IG and FWHM(G) parameters are highly sensitive to the number of GO layers (nGO), which would allow to identify the number of GO layers in a reliable way. Optical reflectance spectra (R(λ)) reveal that plasmons are generated on the surface of nanostructured substrates by the incident radiation. Dips in R(λ) are ascribed as coupling by surface plasmon polaritons described by Bloch waves (BW-SPP). A peak in R(λ) is also observed and it is ascribed to visible radiation produced by Förster resonance energy transfer and Purcell effect. The relevance of these results lies in the possibility of designing colorimetric plasmonic sensors, based on few layers of GO with an excellent control of nGO and with potential in detection of molecules by fluorescent absorption.

Lifelong Maintenance of Oral Tolerance and Immunity Profiles in Mice Depends on Early Exposure to Antigen.

Oral tolerance is defined as a state of systemic hyporesponsiveness to an antigen that has been previously administered by the oral route. Many factors affect oral tolerance induction; some of them related to antigen, and some related to the animal. The age of the animal is one of the most important factors that affect oral tolerance as ageing brings many alterations in immune responses. Herein, we demonstrated that both the oral tolerance and pattern of immune reactivity triggered in early life were kept up to 15 months regarding the magnitude of antibody production, cell proliferation and cytokine profile when compared to immune responses induced in old mice. Therefore, our results corroborate with a promising proposal for prevaccination during childhood and young age, and a booster in older age, to make sure that the primary immunization in early life is not lost in aged individuals.

Protocols for management of oral complications of chemotherapy and/or radiotherapy for oral cancer: Systematic review and meta-analysis current.

BACKGROUND AND OBJECTIVE: Considering the high possibility of dentist consult a patient with oral complications of chemotherapy and/or radiotherapy for oral cancer because of the advances in this area, this study aims to systematically review the literature to identify and suggest effective and safe protocols for the managements of oral complications in oncology patients. MATERIAL AND METHODS: The systematic review was designed by PICO and PRISMA including eligibility and exclusion criteria; the source of information and search strategy in PubMed according MeSH: "Mouth Neoplasms and Radiotherapy" and "Mouth Neoplasms and Drug Therapy" the period from 2010 to 2015; selection and data collection of study was carried form blind and independently by two researchers; risk of bias and methodological quality: ensured by the PEDro scale; synthesis of data: of oral complications were evaluated by adapted version of associative direction classification proposed by Costigan and collaborators; and data analysis was performed by the meta-analysis of BioEstat program (5.0) in the included studies. RESULTS: 2,700 articles found, 2,371 were selected after removal of duplicate and elected 40 full-text articles. Of these, only 06 articles were included in the systematic review with exclusion of others, per obtain punctuation ≥ 7 with high methodological quality for synthesis of the managements of oral complications. Since 05 articles were associated with low risk of bias composing the protocols suggestive for managements and the meta-analysis in odds ratio (0.916) to cure and relative risk (1.049) for the development of oral mucositis and pain. CONCLUSIONS: The protocols suggestive for managements of oral mucositis and pain with MuGard - mucoadhesive hydrogel; PerioAid Tratamiento® antiseptic mouthrinse with chlorhexidine and cetylpyridinium chloride; Episil® plus benzydamine - bioadhesive oromucosal gel; 0,03% of Triclosan mouthwash Colgate Plax; and Diode Laser Therapy of low-level are safe for oncology patients applied according to adopted clinical parameters.

Effects of ulipristal acetate on human embryo attachment and endometrial cell gene expression in an in vitro co-culture system.

STUDY QUESTION: Does ulipristal acetate (UPA) used for emergency contraception (EC) interfere with the human embryo implantation process? SUMMARY ANSWER: UPA, at the dosage used for EC, does not affect human embryo implantation process, in vitro. WHAT IS KNOWN ALREADY: A single pre-ovulatory dose of UPA (30 mg) acts by delaying or inhibiting ovulation and is recommended as first choice among emergency contraceptive pills due to its efficacy. The compound has also been demonstrated to have a dose-dependent effect on the endometrium, which theoretically could impair endometrial receptivity but its direct action on human embryo implantation has not yet been studied. STUDY DESIGN, SIZE, DURATION: Effect of UPA on embryo implantation process was studied in an in vitro endometrial construct. Human embryos were randomly added to the cultures and cultured for 5 more days with UPA (n = 10) or with vehicle alone (n = 10) to record the attachment of embryos. PARTICIPANTS/MATERIALS, SETTING, METHODS: Endometrial biopsies were obtained from healthy, fertile women on cycle day LH+4 and stromal and epithelial cells were isolated. A three-dimensional in vitro endometrial co-culture system was constructed by mixing stromal cells with collagen covered with a layer of epithelial cells and cultured in progesterone containing medium until confluence. The treatment group received 200 ng/ml of UPA. Healthy, viable human embryos were placed on both control and treatment cultures. Five days later the cultures were tested for the attachment of embryos and the 3D endometrial constructs were analysed for endometrial receptivity markers by real-time PCR. MAIN RESULTS AND THE ROLE OF CHANCE: There was no significant difference in the embryo attachment rate between the UPA treated group and the control group as 5 out of 10 human embryos exposed to UPA and 7 out of 10 embryos in the control group attached to the endometrial cell surface (P = 0.650). Out of 17 known receptivity genes studied here, only 2 genes, HBEGF (P = 0.009) and IL6 (P = 0.025) had a significant up-regulation and 4 genes, namely HAND2 (P = 0.003), OPN (P = 0.003), CALCR (P = 0.016) and FGF2 (P = 0.023) were down-regulated with the exposure of UPA, compared with control group. LIMITATIONS, REASONS FOR CAUTION: This proof of concept study was conducted with a few human embryos, as their availability was limited. Although the 3D model used for this study is well established and the artificial endometrial luminal epithelium shown to express progesterone regulated markers of endometrial receptivity it is still an in vitro model, lacking all cell types that constitute the receptive endometrium in vivo. WIDER IMPLICATIONS OF THE FINDINGS: This study provides new insights on the mechanism of action of UPA on human embryo implantation, demonstrating that UPA in a dosage used for EC does not affect embryo viability and the implantation process of embryo. Progesterone receptor modulators (PRMs) hold the potential to be attractive estrogen- and gestagen-free contraceptives and thus may be made available to a larger proportion of women globally due to these findings. STUDY FUNDING/COMPETING INTERESTS: Swedish Research Council (K2010-54X-14212-09-3) and support provided through the regional agreement on medical training and clinical research (ALF) between Stockholm County Council and Karolinska University Hospital.

Ambush strategy enhances organisms' performance in rock-paper-scissors games.

We study a five-species cyclic system wherein individuals of one species strategically adapt their movements to enhance their performance in the spatial rock-paper-scissors game. Environmental cues enable the awareness of the presence of organisms targeted for elimination in the cyclic game. If the local density of target organisms is sufficiently high, individuals move towards concentrated areas for direct attack; otherwise, they employ an ambush tactic, maximising the chances of success by targeting regions likely to be dominated by opponents. Running stochastic simulations, we discover that the ambush strategy enhances the likelihood of individual success compared to direct attacks alone, leading to uneven spatial patterns characterised by spiral waves. We compute the autocorrelation function and measure how the ambush tactic unbalances the organisms' spatial organisation by calculating the characteristic length scale of typical spatial domains of each species. We demonstrate that the threshold for local species density influences the ambush strategy's effectiveness, while the neighbourhood perception range significantly impacts decision-making accuracy. The outcomes show that long-range perception improves performance by over 60%, although there is potential interference in decision-making under high attack triggers. Understanding how organisms' adaptation their environment enhances their performance may be helpful not only for ecologists, but also for data scientists, aiming to improve artificial intelligence systems.

Chronic pain after breast surgery: incidence, risk factors and impact on quality of life.

INTRODUCTION AND OBJECTIVES: Breast cancer is the most frequently diagnosed malignancy, and chronic pain after breast surgery (CPBS) is an increasingly recognized therapy-related problem. We evaluated CPBS incidence, characteristics, associated factors, and impact on patient quality of life (QoL). MATERIALS AND METHODS: Six-month observational prospective study conducted in patients undergoing breast surgery in a tertiary university hospital. Data were collected using several questionnaires: Pain Catastrophizing Scale, Brief Pain Inventory-Short Form, Douleur Neuropathique 4 Questionnaire, and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire and its Breast Cancer Module. RESULTS: A total of 112 patients completed the study. Approximately, one third (34.8%) developed CPBS, and almost all with potentially neuropathic pain. CPBS interfered with patients' daily life and reduced their QoL. Diabetes (p = 0.028), catastrophizing (p = 0.042), and acute postoperative pain severity (p < 0.001) were associated with CPBS. CONCLUSIONS: This study broadens our understanding of CPBS and shows the impact of this syndrome. Healthcare workers need to be aware of CPBS and take steps to prevent and treat it, and provide patients with adequate information.

Dynamics of blaOXA-23 gene transmission in Acinetobacter spp. from contaminated veterinary environmental surfaces: an emerging One Health threat?

BACKGROUND: Carbapenem-resistant Acinetobacter baumannii is a common pathogen associated with healthcare-acquired infections, and robust infection prevention and control protocols exist in human healthcare settings. In contrast, infection prevention and control (IPC) standards are limited in veterinary medicine, necessitating further investigation. AIM: Examine the possible transmission of carbapenem-resistant Acinetobacter spp. in a veterinary practice where a cat was diagnosed with an OXA-23-producing A. baumannii ST2 strain. METHODS: Environmental samples together with nasal and hand swabs from the veterinary personnel were collected. All swabs were screened for the presence of extended-spectrum-ß-lactamase- and carbapenemase-producing Enterobacterales, meticillin-resistant staphylococcus and multi-drug-resistant Acinetobacter spp. Whole-genome sequencing was performed for carbapenemase-producing strains. RESULTS: Of the veterinary staff, 60% carried meticillin-resistant Staphylococcus epidermidis. Environmental evaluation showed that 40% (N=6/15) of the surfaces analysed by contact plates and 40% (N=8/20) by swabs failed the hygiene criteria. Assessment of the surfaces revealed contamination with five OXA-23-producing Acinetobacter spp. strains: an OXA-23-producing Acinetobacter schindleri on the weight scale in the waiting room; and four OXA-23-producing Acinetobacter lwoffii strains, on different surfaces of the treatment room. The blaOXA-23 gene was located on the same plasmid-carrying Tn2008 across the different Acinetobacter spp. strains. These plasmids closely resemble a previously described OXA-23-encoding plasmid from a human Portuguese nosocomial Acinetobacter pittii isolate. Distinctly, the OXA-23-producing A. baumannii ST2 clinical strain had the resistant gene located on Tn2006, possibly inserted on the chromosome. CONCLUSION: The detection of an OXA-23-producing A. baumannii ST2 veterinary clinical strain is of concern for companion animal health and infection, prevention and control. This study established the dynamic of transmission of the plasmid-mediated blaOXA-23 gene on critical surfaces of a small animal veterinary practice. The genetic resemblance to a plasmid found in human nosocomial settings suggests a potential One Health link.

Locally adaptive aggregation of organisms under death risk in rock-paper-scissors models.

We run stochastic simulations of the spatial version of the rock-paper-scissors game, considering that individuals use sensory abilities to scan the environment to detect the presence of enemies. If the local dangerousness level is above a tolerable threshold, individuals aggregate instead of moving randomly on the lattice. We study the impact of the locally adaptive aggregation on the organisms' spatial organisation by measuring the characteristic length scale of the spatial domains occupied by organisms of a single species. Our results reveal that aggregation is beneficial if triggered when the local density of opponents does not exceed 30%; otherwise, the behavioural strategy may harm individuals by increasing the average death risk. We show that if organisms can perceive further distances, they can accurately scan and interpret the signals from the neighbourhood, maximising the effects of the locally adaptive aggregation on the death risk. Finally, we show that the locally adaptive aggregation behaviour promotes biodiversity independently of the organism's mobility. The coexistence probability rises if organisms join conspecifics, even in the presence of a small number of enemies. We verify that our conclusions hold for more complex systems by simulating the generalised rock-paper-scissors models with five and seven species. Our discoveries may be helpful to ecologists in understanding systems where organisms' self-defence behaviour adapts to local environmental cues.

Parental report of dental pain and discomfort in preschool children is associated with sleep disorders: a cross-sectional study in Brazilian families.

PURPOSE: To evaluate the prevalence of sleep disorders in Brazilian preschool children and its associations with parental report of dental pain and discomfort. METHODS: This cross-sectional study involved 604 Brazilian preschoolers (4-5 years old). Sleep disorders (SD) and the parental report of dental pain and discomfort (DPD) were evaluated using the Brazilian versions of the Sleep Disturbance Scale for Children (SDSC) and the Dental Discomfort Questionnaire (DDQ-B), respectively. Bivariate and multivariate Poisson regression analyses with robust variance were performed to analyze the association between SDSC and DP. RESULTS: Prevalence of SD ranged from 7 to 21%. 7.9% of the children had DPD indicating the need for more invasive dental procedures (DDQ-B ≥ 5). Significant associations were found between DPD and the following SDSC domains: sleep hyperhidrosis (p = 0.024; PRa = 1.38; 95% CI: 1.04-1.83), disorders of initiating and maintaining sleep (p < 0.001; PRa = 1.41; 95% CI: 1.15-1.73), parasomnias (p < 0.001; PRa = 1.82; 95% CI: 1.39-2.37), and sleep-wake transition disorders (p = 0.018; PRa = 1.28; 95% CI: 1.04-1.58). Children with higher prevalence of DPD presented 20% higher prevalence of SD than children lower prevalence of DPD (p = 0.039; PRa = 1.20; 95% CI: 1.01-1.44). CONCLUSION: Preschool children with higher prevalence of DPD are more likely to have SD, such as hyperhidrosis, disorders of initiating and maintaining sleep, parasomnias, and sleep-wake transition.

Cell therapy with adipose tissue-derived human stem cells in the urinary bladder improves detrusor contractility and reduces voiding residue.

Detrusor hypocontractility (DH) is a disease without a gold standard treatment in traditional medicine. Therefore, there is a need to develop innovative therapies. The present report presents the case of a patient with DH who was transplanted with 2 x 106 adipose tissue-derived mesenchymal stem cells twice and achieved significant improvements in their quality of life. The results showed that cell therapy reduced the voiding residue from 1,800 mL to 800 mL, the maximum cystometric capacity from 800 to 550 mL, and bladder compliance from 77 to 36.6 mL/cmH2O. Cell therapy also increased the maximum flow from 3 to 11 mL/s, the detrusor pressure from 08 to 35 cmH2O, the urine volume from 267 to 524 mL and the bladder contractility index (BCI) value from 23 to 90. The International Continence on Incontinence Questionnaire - Short Form score decreased from 17 to 8. Given the above, it is inferred that the transplantation of adipose tissue-derived mesenchymal stem cells is an innovative and efficient therapeutic strategy for DH treatment and improves the quality of life of patients affected by this disease.

Hypoglycemic effect of Coffea arabica leaf extracts and major bioactive constituents.

The present study focused on investigating the antioxidant, antiglycation activity, digestive enzymes inhibition, bioaccessibility and hypoglycemic effect of C. arabica leaves extracts. The extracts deactivated the O2•-, ROO•, H2O2, HOCl reactive oxygen species. Coffee leaves showed strong inhibition of α-glucosidase (IC50 = 40.30 µg mL-1) greater than the isolated metabolites and acarbose. There was also inhibition of pancreatic lipase (IC50 = 56.43 µg mL-1) in addition to a hypoglycemic effect in zebrafish similar to acarbose and metformin. With the exception of rutin, all biocompounds were detected at all stages of in vitro digestion. Finally, these results suggest that C. arabica leaf extracts possess antidiabetic and anti-obesity properties that can be attributed to the main metabolites and the synergistic action between them.Communicated by Ramaswamy H. Sarma.

Spatial organisation plasticity reduces disease infection risk in rock-paper-scissors models.

We study a three-species cyclic game system where organisms face a contagious disease whose virulence may change by a pathogen mutation. As a responsive defence strategy, organisms' mobility is restricted to reduce disease dissemination in the system. The impact of the collective self-preservation strategy on the disease infection risk is investigated by performing stochastic simulations of the spatial version of the rock-paper-scissors game. Our outcomes show that the mobility control strategy induces plasticity in the spatial patterns with groups of organisms of the same species inhabiting spatial domains whose characteristic length scales depend on the level of dispersal restrictions. The spatial organisation plasticity allows the ecosystems to adapt to minimise the individuals' disease contamination risk if an eventual pathogen alters the disease virulence. We discover that if a pathogen mutation makes the disease more transmissible or less lethal, the organisms benefit more if the mobility is not strongly restricted, thus forming large spatial domains. Conversely, the benefits of protecting against a pathogen causing a less contagious or deadlier disease are maximised if the average size of groups of individuals of the same species is significantly limited, reducing the dimensions of groups of organisms significantly. Our findings may help biologists understand the effects of dispersal control as a conservation strategy in ecosystems affected by epidemic outbreaks.

Combination of survival movement strategies in cyclic game systems during an epidemic.

Disease outbreaks affect many ecosystems threatening species that also fight against other natural enemies. We investigate a cyclic game system with 5 species, whose organisms outcompete according to the rules of a generalised spatial rock-paper-scissors game, during an epidemic. We study the effects of behavioural movement strategies that allow individuals of one out of the species to move towards areas with a low density of disease vectors and a high concentration of enemies of their enemies. We perform a series of stochastic simulations to discover the impact of self-preservation strategies in pattern formation, calculating the species' spatial autocorrelation functions. Considering organisms with different physical and cognitive abilities, we compute the benefits of each movement tactic to reduce selection and infection risks. Our findings show that the maximum profit in terms of territorial dominance in the cyclic game is achieved if both survival movement strategies are combined, with individuals prioritising social distancing. In the case of an epidemic causing symptomatic illness, the drop in infection risk when organisms identify and avoid disease vectors does not render a rise in the species population because many refuges are disregarded, limiting the benefits of safeguarding against natural enemies. Our results may be helpful to the understanding of the behavioural strategies in ecosystems where organisms adapt to face living conditions changes.

Antipredator behavior in the rock-paper-scissors model.

When faced with an imminent risk of predation, many animals react to escape consumption. Antipredator strategies are performed by individuals acting as a group to intimidate predators and minimize the damage when attacked. We study the antipredator prey response in spatial tritrophic systems with cyclic species dominance using the rock-paper-scissors game. The impact of the antipredator behavior is local, with the predation probability reducing exponentially with the number of prey in the predator's neighborhood. In contrast to the standard Lotka-Volterra implementation of the rock-paper-scissors model, where no spiral waves appear, our outcomes show that the antipredator behavior leads to spiral patterns from random initial conditions. The results show that the predation risk decreases exponentially with the level of antipredator strength. Finally, we investigate the coexistence probability and verify that antipredator behavior may jeopardize biodiversity for high mobility. Our findings may help biologists to understand ecosystems formed by species whose individuals behave strategically to resist predation.

Mobility-limiting antipredator response in the rock-paper-scissors model.

Antipredator behavior is present in many biological systems where individuals collectively react to an imminent attack. The antipredator response may influence spatial pattern formation and ecosystem stability but requires an organism's cost to contribute to the collective effort. We investigate a nonhierarchical tritrophic system, whose predator-prey interactions are described by the rock-paper-scissors game rules. In our spatial stochastic simulations, the radius of antipredator response defines the maximum prey group size that disturbs the predator's action, determining the individual cost to participate in antipredator strategies. We consider that each organism contributes equally to the collective effort, having its mobility limited by the proportion of energy devoted to the antipredator reaction. Our outcomes show that the antipredator response leads to spiral patterns, with the segregation of organisms of the same species occupying departed spatial domains. We found that a less localized antipredator response increases the average size of the single-species patches, improving the protection of individuals against predation. Finally, our findings show that although the increase of the predation risk for a more localized antipredator response, the high mobility constraining benefits species coexistence. Our results may help ecologists understand the mechanisms leading to the stability of biological systems where locality is crucial to behavioral interactions among species.

Behavioural movement strategies in cyclic models.

The spatial segregation of species is fundamental to ecosystem formation and stability. Behavioural strategies may determine where species are located and how their interactions change the local environment arrangement. In response to stimuli in the environment, individuals may move in a specific direction instead of walking randomly. This behaviour can be innate or learned from experience, and allow the individuals to conquer or the maintain territory, foraging or taking refuge. We study a generalisation of the spatial rock-paper-scissors model where individuals of one out of the species may perform directional movement tactics. Running a series of stochastic simulations, we investigate the effects of the behavioural tactics on the spatial pattern formation and the maintenance of the species diversity. We also explore a more realistic scenario, where not all individuals are conditioned to perform the behavioural strategy or have different levels of neighbourhood perception. Our outcomes show that self-preservation behaviour is more profitable in terms of territorial dominance, with the best result being achieved when all individuals are conditioned and have a long-range vicinity perception. On the other hand, invading is more advantageous if part of individuals is conditioned and if they have short-range neighbourhood perception. Finally, our findings reveal that the self-defence strategy is the least jeopardising to biodiversity which can help biologists to understand population dynamics in a setting where individuals may move strategically.

Social preference is maintained in mice with impaired startle reflex and glutamate/D-serine imbalance induced by chronic cerebral toxoplasmosis.

Toxoplasma gondii is an opportunistic protozoan pathogen with a wide geographic distribution. The chronic phase of toxoplasmosis is often asymptomatic in humans and is characterized by tissue cysts throughout the central nervous system and muscle cells. T. gondii and other pathogens with tropism for the central nervous system are considered risk factors in the etiology of several neuropsychiatric disorders, such as schizophrenia and bipolar disorder, besides neurological diseases. Currently, it is known that cerebral toxoplasmosis increases dopamine levels in the brain and it is related to behavioral changes in animals and humans. Here we evaluate whether chronic T. gondii infection, using the cystogenic ME-49 strain, could induce behavioral alterations associated with neuropsychiatric disorders and glutamatergic neurotransmission dysfunction. We observed that the startle amplitude is reduced in the infected animals as well as glutamate and D-serine levels in prefrontal cortical and hippocampal tissue homogenates. Moreover, we did not detect alterations in social preference and spontaneous alternation despite severe motor impairment. Thus, we conclude that behavioral and cognitive aspects are maintained even though severe neural damage is observed by chronic infection of C57Bl/6 mice with the ME-49 strain.