Rapid Physiological Plasticity in Response to Cold Acclimation for Nonnative Italian Wall Lizards (Podarcis siculus) from New York.

AbstractThermal physiology helps us understand how ectotherms respond to novel environments and how they persist when introduced to new locations. Researchers generally measure thermal physiology traits immediately after animal collection or after a short acclimation period. Because many of these traits are plastic, the conclusions drawn from such research can vary depending on the duration of the acclimation period. In this study, we measured the rate of change and extent to which cold tolerance (critical thermal minimum [CTmin]) of nonnative Italian wall lizards (Podarcis siculus) from Hempstead, New York, changed during a cold acclimation treatment. We also examined how cold acclimation affected heat tolerance (critical thermal maximum [CTmax]), thermal preference (Tpref), evaporative water loss (EWL), resting metabolic rate (RMR), and respiratory exchange ratio (RER). We predicted that CTmin, CTmax, and Tpref would decrease with cold acclimation but that EWL and RMR would increase with cold acclimation. We found that CTmin decreased within 2 wk and that it remained low during the cold acclimation treatment; we suspect that this cold tolerance plasticity reduces risk of exposure to lethal temperatures during winter for lizards that have not yet found suitable refugia. CTmax and Tpref also decreased after cold acclimation, while EWL, RMR, and RER increased after cold acclimation, suggesting trade-offs with cold acclimation in the form of decreased heat tolerance and increased energy demands. Taken together, our findings suggest that cold tolerance plasticity aids the persistence of an established population of invasive lizards. More generally, our findings highlight the importance of accounting for the plasticity of physiological traits when investigating how invasive species respond to novel environments.

Striatal synaptic changes and behavior in adult mouse upon prenatal exposure to valproic acid.

Autism spectrum disorders (ASD) are a group of neurodevelopmental disorders characterized by persistent deficits in social communication and social interaction. Altered synaptogenesis and aberrant connectivity responsible for social behavior and communication have been reported in autism pathogenesis. Autism has a strong genetic and heritable component; however, environmental factors including toxins, pesticides, infection and in utero exposure to drugs such as VPA have also been implicated in ASD. Administration of VPA during pregnancy has been used as a rodent model to study pathophysiological mechanisms involved in ASD, and in this study, we used the mouse model of prenatal exposure to VPA to assess the effects on striatal and dorsal hippocampus function in adult mice. Alterations in repetitive behaviors and shift habits were observed in mice prenatally exposed to VPA. In particular, such mice presented a better performance in learned motor skills and cognitive deficits in Y-maze learning frequently associated with striatal and hippocampal function. These behavioral changes were associated with a decreased level of proteins involved in the formation and maintenance of excitatory synapses, such as Nlgn-1 and PSD-95. In conclusion, motor skill abilities, repetitive behaviors, and impaired flexibility to shift habits are associated with reduced striatal excitatory synaptic function in the adult mouse prenatally exposed to VPA.

Osmotic and metabolic responses to cold acclimation and acute cold challenge in a freeze avoidant lizard, Podarcis siculus.

Ectotherms survive exposure to subzero temperatures through freeze tolerance or freeze avoidance. Among vertebrate ectotherms, glucose is commonly used as a cryoprotectant in freeze tolerant strategies and as an osmolyte in freeze avoidant strategies, while also functioning as a metabolic substrate. Whereas some lizard species are capable of both freeze tolerance and freeze avoidance, Podarcis siculus is limited to freeze avoidance through supercooling. We hypothesized that, even in a freeze-avoidant species such as P. siculus, plasma glucose would accumulate with cold acclimation and would increase in response to acute exposure to subzero temperatures. To investigate this, we tested whether plasma glucose concentration and osmolality would increase in response to a subzero cold challenge before and after cold acclimation. In addition, we examined the relationship between metabolic rate, cold acclimation, and glucose by measuring metabolic rate during the cold challenge trials. We found that plasma glucose increased during the cold challenge trials, and that the increase was more pronounced after cold acclimation. However, baseline plasma glucose decreased throughout cold acclimation. Interestingly, total plasma osmolality did not change, and the increase in glucose only slightly altered freezing point depression. Metabolic rate during the cold challenge decreased after cold acclimation, and changes in respiratory exchange ratio suggest an increased relative use of carbohydrates. Overall, our findings demonstrate an important role for glucose in the response of P. siculus to an acute cold challenge, thus adding evidence for glucose as an important molecule for overwintering ectotherms that use freeze avoidant strategies.

Glial cells in anorexia.

Anorexia is a loss of appetite or an inability to eat and is often associated with eating disorders. However, animal anorexia is physiologically regulated as a part of the life cycle; for instance, during hibernation, migration or incubation. Anorexia nervosa (AN), on the other hand, is a common eating disorder among adolescent females that experience an intense fear of gaining weight due to body image distortion that results in voluntary avoidance of food intake and, thus, severe weight loss. It has been shown that the neurobiology of feeding extends beyond the hypothalamus. The prefrontal cortex (PFC) is involved in food choice and body image perception, both relevant in AN. However, little is known about the neurobiology of AN, and the lack of effective treatments justifies the use of animal models. Glial cells, the dominant population of nerve cells in the central nervous system, are key in maintaining brain homeostasis. Accordingly, recent studies suggest that glial function may be compromised by anorexia. In this review, we summarize recent findings about anorexia and glial cells.

Environmental Enrichment Differentially Activates Neural Circuits in FVB/N Mice, Inducing Social Interaction in Females but Agonistic Behavior in Males.

Environmental enrichment induces behavioral and structural modifications in rodents and influences the capability of mice to cope with stress. However, little is understood about hippocampal neurogenesis and the appearance of social/agonistic (aggressive) behavior upon activation of different neuronal circuits in FVB/N mice. Thus, in this study we hypothesized that environmental enrichment differentially regulates neurogenesis, neural circuit activation and social/agonistic behavior in male and female FVB/N mice. We explored the (1) neurogenic process as an indicative of neuroplasticity, (2) neuronal activation in the limbic system, and (3) social behavior using the resident-intruder test. On postnatal day 23 (PD23), mice were assigned to one of two groups: Standard Housing or Environmental Enrichment. At PD53, rodents underwent the resident-intruder test to evaluate social behaviors. Results revealed that environmental enrichment increased neurogenesis and social interaction in females. In males, environmental enrichment increased neurogenesis and agonistic behavior. Enriched male mice expressed higher levels of agonistic-related behavior than female mice housed under the same conditions. Neural circuit analysis showed lower activation in the amygdala of enriched males and higher activation in enriched females than their respective controls. Enriched females also showed higher activation in the frontal cortex without differences in male groups. Moreover, the insular cortex was less activated in females than in males. Thus, our results indicate that environmental enrichment has different effects on neuroplasticity and social/agonistic behavior in FVB/N mice, suggesting the relevance of sexual dimorphism in response to environmental stimuli.

Anorexia disrupts glutamate-glutamine homeostasis associated with astroglia in the prefrontal cortex of young female rats.

Anorexia nervosa (AN) is an eating disorder characterized by self-starvation and excessive weight loss with a notorious prevalence in young women. The neurobiology of AN is unknown but murine models, like dehydration induced anorexia (DIA), reproduce weight loss and avoidance of food despite its availability. Astrocytes are known to provide homeostatic support to neurons, but it is little explored if anorexia affects this function. In this study, we tested if DIA disrupts glutamate-glutamine homeostasis associated with astrocytes in the prefrontal cortex (PFC) of young female rats. Our results showed that anorexia reduced the redox state, as well as endogenous glutamate and glutamine. These effects correlated with a reduced expression of the glutamate transporters (GLT-1 and GLAST) and glutamine synthetase, all of them are preferentially expressed by astrocytes. Accordingly, the expression of GFAP was reduced. Anorexia reduced the astrocyte density, promoted a de-ramified morphology, and augmented the de-ramified/ramified astrocyte ratio in the medial prefrontal cortex (mPFC) and orbitofrontal cortex (OFC), but not in the motor cortex (M2). The increase of a de-ramified phenotype correlated with increased expression of vimentin and nestin. Based on these results, we conclude that anorexia disrupts glutamate-glutamine homeostasis and the redox state associated with astrocyte dysfunction.

A Functional Signature in the Developing Cerebellum: Evidence From a Preclinical Model of Autism.

Autism spectrum disorders (ASD) are pervasive neurodevelopmental conditions detected during childhood when delayed language onset and social deficits are observed. Children diagnosed with ASD frequently display sensorimotor deficits associated with the cerebellum, suggesting a dysfunction of synaptic circuits. Astroglia are part of the tripartite synapses and postmortem studies reported an increased expression of the glial fibrillary acidic protein (GFAP) in the cerebellum of ASD patients. Astroglia respond to neuronal activity with calcium transients that propagate to neighboring cells, resulting in a functional response known as a calcium wave. This form of intercellular signaling is implicated in proliferation, migration, and differentiation of neural precursors. Prenatal exposure to valproate (VPA) is a preclinical model of ASD in which premature migration and excess of apoptosis occur in the internal granular layer (IGL) of the cerebellum during the early postnatal period. In this study we tested calcium wave propagation in the IGL of mice prenatally exposed to VPA. Sensorimotor deficits were observed and IGL depolarization evoked a calcium wave with astrocyte recruitment. The calcium wave propagation, initial cell recruitment, and mean amplitude of the calcium transients increased significantly in VPA-exposed mice compared to the control group. Astrocyte recruitment was significantly increased in the VPA model, but the mean amplitude of the calcium transients was unchanged. Western blot and histological studies revealed an increased expression of GFAP, higher astroglial density and augmented morphological complexity. We conclude that the functional signature of the IGL is remarkably augmented in the preclinical model of autism.

Heat hardening in a pair of Anolis lizards: constraints, dynamics and ecological consequences.

Heat tolerance plasticity is predicted to be an important buffer against global warming. Nonetheless, basal heat tolerance often correlates negatively with tolerance plasticity ('trade-off hypothesis'), a constraint that could limit plasticity benefits. We tested the trade-off hypothesis at the individual level with respect to heat hardening in two lizard species, Anolis carolinensis and Anolis sagrei. Heat hardening is a rapid increase in heat tolerance after heat shock that is rarely measured in reptiles but is generally considered to be a first line of physiological defense against heat. We also employed a biophysical model of operative habitat temperatures to estimate the performance consequences of hardening under ecologically relevant conditions. Anolis carolinensis hardened by 2 h post-heat shock and maintained hardening for several hours. However, A. sagrei did not harden. Biophysical models showed that hardening in A. carolinensis reduces their overheating risk in the field. Therefore, while not all lizards heat harden, hardening has benefits for species that can. We initially found a negative relationship between basal tolerance and hardening within both species, consistent with the trade-off hypothesis. However, permutation analyses showed that the apparent trade-offs could not be differentiated from statistical artifact. We found the same result when we re-analyzed published data supporting the trade-off hypothesis in another lizard species. Our results show that false positives may be common when testing the trade-off hypothesis. Statistical approaches that account for this are critical to ensure that the hypothesis, which has broad implications for thermal adaptation and responses to warming, is assessed appropriately.

Métodos de Registro de Dimensión Vertical Oclusal en Pacientes Dentados: Revisión Sistemática

RESUMEN: La Dimensión Vertical Oclusal, es la distancia entre un punto anatómico fijo en el maxilar y otro sobre la parte móvil de la mandíbula cuando los órganos dentarios están en contacto oclusal. La obtención de este registro determina el espacio vertical necesario para la rehabilitación de los pacientes. En la actualidad existen distintos métodos para el registro de la Dimensión Vertical Oclusal, en este estudio se analizaron: Métodos fisiológicos y métodos mecánicos. El objetivo fue realizar una revisión sistemática, sobre los métodos de registro, para determinar la Dimensión Vertical Oclusal en pacientes dentados. Se recopiló información científica desde Mayo 2019 hasta Julio 2020 en diferentes bases de datos electrónicas, encontrando un tota l de 13948 artículos, después de eliminar artículos repetidos, por título, por resumen y por metodología PICO se seleccionaron un total de 24 artículos para su análisis y clasificación. Más de un autor menciona que no existe un método unirversalmente aceptado o exacto para determinar la Dimensión Vertical Oclusal. Se sugiere la combinación de varios métodos de registro de Dimensión Vertical Oclusal, se debe de considerar la manera más adecuada para lograr un registro más acertado.

ABSTRACT: Occlusal Vertical Dimension is the distance between an anatomical point in the maxilla and another on the mobile part of the mandible when the teeth are in occlusal contact. Obtaining this record determines the vertical space necessary for the rehabilitation of patients. Nowadays there are different methods for the record of the Occlusal Vertical Dimension, in this study the following were analyzed: physiological methods and mechanical methods. The objective was to do a systematic review of the registration methods to determine the Occlusal Vertical Dimension in dentate patients. Scientific information was collected from May 2019 to July 2020 in different electronic databases, finding a total of 13,948 articles, after eliminating repeated articles, by title, by abstract and by PICO methodology, a total of 24 articles were selected for analysis and classification. More than one author mentions that there is no universally accepted or exact method for determining Occlusal Vertical Dimension. A combination of several methods of Occlusal Vertical Dimension registration is suggested; it should be considered the most appropriate way to achieve a more accurate registration.

Therapeutic Potential of GABAergic Signaling in Myelin Plasticity and Repair.

Oligodendrocytes (OLs) produce myelin to insulate axons. This accelerates action potential propagation, allowing nerve impulse information to synchronize within complex neuronal ensembles and promoting brain connectivity. Brain plasticity includes myelination, a process that starts early after birth and continues throughout life. Myelin repair, followed by injury or disease, requires new OLs differentiated from a population derived from oligodendrocyte precursor cells (OPCs) that continue to proliferate, migrate and differentiate to preserve and remodel myelin in the adult central nervous system. OPCs represent the largest proliferative neural cell population outside the adult neurogenic niches in the brain. OPCs receive synaptic inputs from glutamatergic and GABAergic neurons throughout neurodevelopment, a unique feature among glial cells. Neuron-glia communication through GABA signaling in OPCs has been shown to play a role in myelin plasticity and repair. In this review we will focus on the molecular and functional properties of GABA A receptors (GABA A Rs) expressed by OPCs and their potential role in remyelination.

Heat hardening in a pair of Anolis lizards: constraints, dynamics and ecological consequences.

Heat tolerance plasticity is predicted to be an important buffer against global warming. Nonetheless, basal heat tolerance often correlates negatively with tolerance plasticity ('trade-off hypothesis'), a constraint that could limit plasticity benefits. We tested the trade-off hypothesis at the individual level with respect to heat hardening in two lizard species, Anolis carolinensis and Anolis sagrei Heat hardening is a rapid increase in heat tolerance after heat shock that is rarely measured in reptiles but is generally considered to be a first line of physiological defense against heat. We also employed a biophysical model of operative habitat temperatures to estimate the performance consequences of hardening under ecologically relevant conditions. Anolis carolinensis hardened by 2 h post-heat shock and maintained hardening for several hours. However, A. sagrei did not harden. Biophysical models showed that hardening in A. carolinensis reduces their overheating risk in the field. Therefore, while not all lizards heat harden, hardening has benefits for species that can. We initially found a negative relationship between basal tolerance and hardening within both species, consistent with the trade-off hypothesis. However, permutation analyses showed that the apparent trade-offs could not be differentiated from statistical artifact. We found the same result when we re-analyzed published data supporting the trade-off hypothesis in another lizard species. Our results show that false positives may be common when testing the trade-off hypothesis. Statistical approaches that account for this are critical to ensure that the hypothesis, which has broad implications for thermal adaptation and responses to warming, is assessed appropriately.

Transcriptome-wide Cas13 guide RNA design for model organisms and viral RNA pathogens.

The recent characterization of RNA-targeting CRISPR nucleases has enabled diverse transcriptome engineering and screening applications that depend crucially on prediction and selection of optimized CRISPR guide RNAs (gRNAs). Previously, we developed a computational model to predict RfxCas13d gRNA activity for all human protein-coding genes. Here, we extend this framework to six model organisms (human, mouse, zebrafish, fly, nematode, and flowering plants) for protein-coding genes and noncoding RNAs (ncRNAs) and also to four RNA virus families (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2], HIV-1, H1N1 influenza, and Middle East respiratory syndrome [MERS]). We include experimental validation of predictions by testing knockdown of multiple ncRNAs (MALAT1, HOTAIRM1, Gas5, and Pvt1) in human and mouse cells. We developed a freely available web-based platform (cas13design) with pre-scored gRNAs for transcriptome-wide targeting in several organisms and an interactive design tool to predict optimal gRNAs for custom RNA targets entered by the user. This resource will facilitate CRISPR-Cas13 RNA targeting in model organisms, emerging viral threats to human health.

Anorexia induces a microglial associated pro-inflammatory environment and correlates with neurodegeneration in the prefrontal cortex of young female rats.

Dehydration-Induced Anorexia (DIA) is a murine model that reproduces weight loss and avoidance of food, despite its availability. The prefrontal cortex (PFC) integrates sensory inputs and updates associative learning to promote (hunger) or inhibit (satiety) food-seeking behavior. In this study we tested if anorexia induces a pro-inflammatory environment associated with microglia in the medial prefrontal cortex (mPFC) and orbitofrontal cortex (OFC), specific subregions of the PFC involved in appetite. Our results showed that anorexia increased microglial density, promoted a de-ramified morphology and augmented the de-ramified/ramified ratio in the mPFC and OFC but not in the motor cortex. Anorexia also increased the expression of the pro-inflammatory cytokines TNF-α, IL-6 and IL-1ß. This pro-inflammatory environment associated with microglia activation correlates with neuronal damage as revealed by Fluoro Jade C (FJC) and NeuN immunolabeling. We conclude that anorexia triggers a pro-inflammatory environment associated with microglia that correlates with neurodegeneration in the mPFC and OFC.

GABAA Receptors are Selectively Expressed in NG2 Glia of the Cerebellar White Matter.

The cerebellum is involved in the coordination of movement. Its cellular composition is dominated by GABAergic neuronal types, and glial cells are known to express functional receptors. GABAergic signaling regulates cell proliferation, differentiation, and migration during neurodevelopment. However, little is known about the functional expression of GABA receptors in the cerebellar white matter (WM). Thus, the aim of this study was to test whether glial cells express functional GABA receptors during postnatal development (P7-P9) of cerebellar WM. Immunofluorescence showed that half of the astrocytes express GAD67, suggesting that glial cells synthesize GABA. Calcium imaging in cerebellar slices revealed that GABA and the GABAA agonist muscimol evoked calcium transients in sulforhodamine B negative cells, whereas the GABAB agonist baclofen failed to evoke responses in cerebellar WM. Whole-cell patch-clamp recordings of GFAP+ cells showed dye coupling and a passive current-voltage relation typical of astrocytes. Surprisingly, these cells did not respond to muscimol. Two additional populations were identified as GFAP- cells. The first population showed dye coupling, slow decaying inward and outward currents with no voltage dependence, and did not respond to GABAA agonists. The second population showed an outward-rectifying current-voltage relationship and responded to muscimol, but dye coupling was absent. These cells received synaptic input and were NG2+, but evoked calcium waves failed to modulate the frequency of spontaneous postsynaptic currents (sPSCs) or signaling into NG2 glia. We conclude that GABAA receptor-mediated signaling is selective for NG2 glia in the WM of the cerebellum.

Relationship between skin and urine colonization and surgical site infection in the proximal femur fracture: a prospective study.

PURPOSE: Antibiotic prophylaxis is routinely used in the surgical management of proximal femur fractures. The role of bacterial colonization of the skin and urine in the development of deep surgical site infections (SSI) is yet to be elucidated. This study aimed to evaluate the role of previous skin and urine colonization in the development of deep SSI after a proximal femoral fracture surgery. METHODS: We conducted a prospective observational study in 326 patients > 64 years old, who were scheduled to surgery. Cultures from skin samples of the surgical site and from urine were performed prior to the procedure, and cefazoline was administered as prophylaxis. RESULTS: Skin microbiota was isolated in 233 (71.5%) cases; 8 (2.5%) samples were positive for other bacteria, and 85 (26%) were negative. Of 236 urine samples, 168 were negative or contaminated (71.2%), and 68 (28.8%) were positive, being 58/236 for Enterobacterales (24.6%). Acute deep SSI were diagnosed in nine out of 326 patients (2.7%), and two (22%) were infected by Gram-negative bacilli. Of the 9 cases, normal skin microbiota was isolated in 7 (78%), and the remaining two were negative. Seven cases had negative or contaminated urine cultures, and the one with E. coli did not correlate with SSI bacteria. CONCLUSION: In our elderly hip fracture population, most patients harbored normal skin microbiota, and Enterobacterales urine cultures were positive in one-quarter of cases. There was no relationship between skin colonization, urine culture, and deep SSI. We therefore do not believe that our patients would benefit from modifying the current antibiotic prophylaxis.

Prevalence and Temporal Characteristics of Housing Needs in an Urban Emergency Department.

INTRODUCTION: Our objective was to determine the proportion of patients in our emergency department (ED) who are unhoused or marginally housed and when they typically present to the ED. METHODS: We surveyed patients in an urban, safety-net ED from June-August 2018, using a sampling strategy that met them at all times of day, every day of the week. Patients used two social needs screening tools with additional questions on housing during sampling shifts representing two full weeks. Housing status was determined using items validated for housing stability, including PRAPARE, the Accountable Health Communities Survey, and items from the United States Department of Health and Human Services. Propensity scores estimated differences among respondents and non-respondents. RESULTS: Of those surveyed, 35% (95% confidence interval [CI], 31-38) identified as homeless and 28% (95% CI, 25-31) as unstably housed. Respondents and non-respondents were similar by propensity score. The average cumulative number of homeless and unstably housed patients arriving per daily 8-hour window peaks at 7 AM, with 46% (95% CI, 29-64) of the daily aggregate of those reporting homelessness and 44% (95% CI, 24-64) with unstable housing presenting over the next eight hours. CONCLUSION: The ED represents a low-barrier contact point for reaching individuals experiencing housing challenges, who may interact rarely with other institutions. The current prevalence of homelessness and housing instability among urban ED patients may be substantially higher than reported in historical and national-level statistics. Housing services offered within normal business hours would reach a meaningful number of those who are unhoused or marginally housed.

A Nonopioid, Nonbenzodiazepine Treatment Approach for Intractable Nausea and Vomiting in the Emergency Department.

GOAL: We sought to assess the feasibility and efficacy of a treatment protocol for nausea and vomiting using the combination of chlorpromazine, a dopamine antagonist antiemetic, and ketamine, a nonopioid analgesic. BACKGROUND: Increasing numbers of patients with cannabis use disorder are presenting to emergency departments with a poorly understood syndrome characterized by intractable nausea and vomiting. METHODS: This is a prospective, observational study involving a convenience sample of patients with unexplained nausea and vomiting. Subjects were given ketamine 15 mg slow intravenous push and chlorpromazine 12.5 mg intravenous over 15 minutes. Outcomes were number of episodes of emesis after study drug administration; change in nausea severity; change in pain severity; adverse events; and patient satisfaction. RESULTS: We enrolled 28 subjects on 30 emergency department visits. Twenty-three subjects (82%) reported at least weekly cannabis use with 19 reporting daily use. Initial symptoms were severe, with median pain and nausea scores both 10. After receiving study medication, the mean decrease in pain score over 120 minutes was 4.1 (95% confidence interval: 3.2, 5.0) and the mean decrease in nausea score was 4.9 (95% confidence interval: 4.0, 5.8). There were no adverse events. All 28 subjects who were asked reported they would want to receive these medications again. CONCLUSION: In this single-center study, the majority of patients presenting with intractable nausea and vomiting reported heavy cannabis use, and symptoms were severe. The combination of chlorpromazine plus ketamine resulted in rapid, definitive cessation of symptoms in most of these patients without the need for opioids or benzodiazepines.

Anorexia increases microglial density and cytokine expression in the hippocampus of young female rats.

Anorexia by osmotic dehydration is an adaptive response to hypernatremia and hyperosmolaemia induced by ingestion of a hypertonic solution. Dehydration-induced anorexia (DIA) reproduces weight loss and avoidance of food, despite its availability. By using this model, we previously showed increased reactive astrocyte density in the rat dorsal hippocampus, suggesting a pro-inflammatory environment where microglia may play an important role. However, whether such anorexic condition increases a pro-inflammatory response is unknown. The aim of this study was to test if DIA increases microglial density in the dorsal hippocampus, as well as the expression of pro-inflammatory cytokines tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6) and interleukin 1 beta (IL-1ß) in the hippocampus of young female rats. Our results showed that DIA significantly increased microglial density in CA2-CA3 and dentate gyrus (DG) but not in CA1. However, forced food restriction (FFR) only increased microglial density in the DG. Accordingly, the activated/resting microglia ratio was significantly increased in CA2-CA3 and DG, in DIA and FFR groups. Finally, western blot analysis showed increased expression of IBA1, TNF-α, IL-6 and IL-1ß in the hippocampus of both experimental groups. We conclude that anorexia triggers increased reactive microglial density and expression of TNF-α, IL-6 and IL-1ß; this environment may result in hippocampal neuroinflammation.

Thermal tolerance varies with age and sex for the nonnative Italian Wall Lizard (Podarcis siculus) in Southern California.

Temperature has a substantial effect on both the physiology and behavior of ectothermic animals such as lizards. Physiology and behavior can also be influenced by ontogenetic and sex differences, but these effects are largely understudied in lizards. We examined ontogenetic and sex-based differences in thermal tolerances, preferred temperature, and temperature-dependent evaporative water loss rates in Italian Wall Lizards, Podarcis siculus, collected from an introduced population near Los Angeles, California, USA that were acclimated to laboratory conditions. Podarcis siculus has been introduced to multiple localities in the USA and the Mediterranean region and has demonstrated remarkable ability to adapt to novel climatic conditions. In the California population, adults of both sexes had a higher critical thermal maximum (CTmax) than juveniles, and adult females had a lower critical thermal minimum (CTmin) than juveniles and adult males. Thus, adult females had a significantly wider thermal breadth (CTmax - CTmin) compared to adult males and juveniles. Mass-specific evaporative water loss was higher in juveniles compared to adult males at intermediate temperatures. There was no significant difference among groups for preferred temperature. This implies that thermal tolerance, a physiological characteristic, varies with age and sex for this population, whereas thermal preference, a behavioral characteristic, does not. Interestingly, CTmin for all age and sex classes was above temperatures likely experienced by some nonnative populations in winter, suggesting individuals need to find urban thermal retreats. These results add to the growing literature demonstrating that thermal tolerances and breadths can vary between sexes and across age classes in squamate species.