The activation of D2-like dopamine receptors increases NMDA currents in the dorsal raphe serotonergic neurons.

The dorsal raphe nucleus (DRN) receives dopaminergic inputs from the ventral tegmental area (VTA). Also, the DRN contains a small population of cells that express dopamine (DRNDA neurons). However, the physiological role of dopamine (DA) in the DRN and its interaction with serotonergic (5-HT) neurons is poorly understood. Several works have reported moderate levels of D1, D2, and D3 DA receptors in the DRN. Furthermore, it was found that the activation of D2 receptors increased the firing of putative 5-HT neurons. Other studies have reported that D1 and D2 dopamine receptors can interact with glutamate NMDA receptors, modulating the excitability of different cell types. In the present work, we used immunocytochemical techniques to determine the kind of DA receptors in the DRN. Additionally, we performed electrophysiological experiments in brainstem slices to study the effect of DA agonists on NMDA-elicited currents recorded from identified 5-HT DRN neurons. We found that D2 and D3 but not D1 receptors are present in this nucleus. Also, we demonstrated that the activation of D2-like receptors increases NMDA-elicited currents in 5-HT neurons through a mechanism involving phospholipase C (PLC) and protein kinase C (PKC) enzymes. Possible physiological implications related to the sleep-wake cycle are discussed.

The evolution of entomopathogeny in nematodes.

Understanding how parasites evolved is crucial to understand the host and parasite interaction. The evolution of entomopathogenesis in rhabditid nematodes has traditionally been thought to have occurred twice within the phylum Nematoda: in Steinernematidae and Heterorhabditidae families, which are associated with the entomopathogenic bacteria Xenorhabdus and Photorhabdus, respectively. However, nematodes from other families that are associated with entomopathogenic bacteria have not been considered to meet the criteria for "entomopathogenic nematodes." The evolution of parasitism in nematodes suggests that ecological and evolutionary properties shared by families in the order Rhabditida favor the convergent evolution of the entomopathogenic trait in lineages with diverse lifestyles, such as saprotrophs, phoretic, and necromenic nematodes. For this reason, this paper proposes expanding the term "entomopathogenic nematode" considering the diverse modes of this attribute within Rhabditida. Despite studies are required to test the authenticity of the entomopathogenic trait in the reported species, they are valuable links that represent the early stages of specialized lineages to entomopathogenic lifestyle. An ecological and evolutionary exploration of these nematodes has the potential to deepen our comprehension of the evolution of entomopathogenesis as a convergent trait spanning across the Nematoda.

Insulin decreases epileptiform activity in rat layer 5/6 prefrontal cortex in vitro.

Accumulating evidence indicates that insulin-mediated signaling in the brain may play important roles in regulating neuronal function. Alterations to insulin signaling are associated with the development of neurological disorders including Alzheimer's disease and Parkinson's disease. Also, hyperglycemia and insulin resistance have been associated with seizure activity and brain injury. In recent work, we found that insulin increased inhibitory GABAA -mediated tonic currents in the prefrontal cortex (PFC). In this work, we used local field potential recordings and calcium imaging to investigate the effect of insulin on seizure-like activity in PFC slices. Seizure-like events (SLEs) were induced by perfusing the slices with magnesium-free artificial cerebrospinal fluid (ACSF) containing the proconvulsive compound 4-aminopyridine (4-AP). We found that insulin decreased the frequency, amplitude, and duration of SLEs as well as the synchronic activity of PFC neurons evoked by 4-AP. These insulin effects were mediated by the PI3K/Akt signaling pathway and mimicked by gaboxadol (THIP), a δ GABAA receptor agonist. The effect of insulin on the number of SLEs was partially blocked by L-655,708, an inverse agonist with high selectivity for GABAA receptors containing the α5 subunit. Our results suggest that insulin reduces neuronal excitability by an increase of GABAergic tonic currents. The physiological relevance of these findings is discussed.

[Restoring horizontal stability in III-V acromioclavicular dislocations by anatomic reconstruction of the coracoclavicular and acromioclavicular ligaments; surgical technique]. / Restablecimiento de la estabilidad horizontal en luxaciones acromioclaviculares III-V mediante la reconstrucción anatómica de los ligamentos coracoclaviculares y acromioclaviculares; técnica quirúrgica.

INTRODUCTION: dislocation of the acromioclavicular (AC) joint is a common injury seen in young adults. The objective is to describe a surgical technique that can restore the horizontal and vertical stability of the AC joint. MATERIAL AND METHODS: we describe a surgical technique that can restore horizontal and vertical stability using an allograft for the anatomical reconstruction of the CC and AC ligaments, for AC grade III-V dislocations according to the Rockwood classification. RESULTS: this is a surgical technique with anatomical and biological reconstruction of the CC and AC ligaments, using an allograft. Two bone tunnels are made in the clavicle, passing the lateral end of the graft below the acromion; then the two ends are fixed with two bioabsorbable screws, restoring vertical and horizontal stability. CONCLUSION: this procedure allows to restore the vertical and horizontal stability of the AC joint. Follow up studies are required to report functional and radiological results, in order to ensure advantages compared to existing techniques.

INTRODUCCIÓN: la luxación de la articulación acromioclavicular (AC) es una lesión frecuente que se observa en adultos jóvenes. El objetivo es describir una técnica quirúrgica que pueda restablecer la estabilidad horizontal y vertical de la articulación AC. MATERIAL Y MÉTODOS: se describe una técnica quirúrgica utilizando un aloinjerto para la reconstrucción anatómica de los ligamentos coracoclaviculares (CC) y AC para luxaciones AC grado III-V de acuerdo con la clasificación de Rockwood. RESULTADOS: es una técnica quirúrgica con reconstrucción anatómica y biológica de los ligamentos CC y AC con injerto. Se realizan dos túneles óseos en la clavícula pasando el cabo lateral del injerto por debajo del acromion; posteriormente se fijan los dos cabos con dos tornillos bioabsorbibles, restaurando de esta manera la estabilidad vertical y horizontal. CONCLUSIÓN: este procedimiento permite restablecer la estabilidad vertical y horizontal de la articulación AC. Se requieren estudios de seguimiento para reportar resultados funcionales y radiológicos con el fin de poder asegurar ventajas en comparación con las técnicas existentes.

Brain MRI without anesthesia in children less than 3 months old.

INTRODUCTION: The use of general anesthesia in infants involves both short-term and long-term risks. The aim of this study is to evaluate the efficacy of brain MRI without anesthesia in infants younger than 3-month-old immobilized with a pillow. PATIENTS AND METHODS: This prospective case-control study was done in 2019. Cases were stable patients less than 3 months old who did not require ventilatory support for whom brain MRI was indicated. Patients were fed so they would fall asleep and placed in the scanner with an immobilizing pillow. Controls were clinically unstable patients matched for age and sex referred for brain MRI under general anesthesia. Three pediatric radiologists evaluated the success of the MRI study (whether it answered the clinical question), recorded whether it was necessary to repeat the study, and rated the presence of motion artifacts on a scale ranging from 1 to 4. RESULTS: A total of 47 cases were included (28 boys and 19 girls; mean age, 31 days). Of these, 42 (89%) MRI studies were considered successful. The proportion of successful MRI studies was lower in outpatients than in inpatients (p = 0.02). The quality of MRI in cases was considered optimal in 60% and suboptimal (motion artifacts in one or two sequences) in 30%. No safety issues related with the technique were detected. The mean duration of the studies was 16.6 min (range, 6-30 min). All of the MRI studies in controls were considered successful; quality was considered optimal in 89% and suboptimal in 11%. In the first year in which we used this technique, we avoided the use of general anesthesia in 47 MRI studies in 42 newborns. CONCLUSION: Brain MRI using the feed and sleep technique in infants younger than 3-month-old immobilized with a pillow can be done safely and efficaciously without general anesthesia.

The percentage of CD39+ monocytes is higher in pregnant COVID-19+ patients than in nonpregnant COVID-19+ patients.

Current medical guidelines consider pregnant women with COVID-19 to be a high-risk group. Since physiological gestation downregulates the immunological response to maintain "maternal-fetal tolerance", SARS-CoV-2 infection may constitute a potentially threatening condition to both the mother and the fetus. To establish the immune profile in pregnant COVID-19+ patients, a cross-sectional study was conducted. Pregnant women with COVID-19 (P-COVID-19+; n = 15) were analyzed and compared with nonpregnant women with COVID-19 (NP-COVID-19+; n = 15) or those with physiological pregnancy (P-COVID-19-; n = 13). Serological cytokine and chemokine concentrations, leucocyte immunophenotypes, and mononuclear leucocyte responses to polyclonal stimuli were analyzed in all groups. Higher concentrations of serological TNF-α, IL-6, MIP1b and IL-4 were observed within the P-COVID-19+ group, while cytokines and chemokines secreted by peripheral leucocytes in response to LPS, IL-6 or PMA-ionomicin were similar among the groups. Immunophenotype analysis showed a lower percentage of HLA-DR+ monocytes in P-COVID-19+ than in P-COVID-19- and a higher percentage of CD39+ monocytes in P-COVID-19+ than in NP-COVID-19+. After whole blood polyclonal stimulation, similar percentages of T cells and TNF+ monocytes between groups were observed. Our results suggest that P-COVID-19+ elicits a strong inflammatory response similar to NP-COVID19+ but also displays an anti-inflammatory response that controls the ATP/adenosine balance and prevents hyperinflammatory damage in COVID-19.

Restablecimiento de la estabilidad horizontal en luxaciones acromioclaviculares III-V mediante la reconstrucción anatómica de los ligamentos coracoclaviculares y acromioclaviculares; técnica quirúrgica / Restoring horizontal stability in III-V acromioclavicular dislocations by anatomic reconstruction of the coracoclavicular and acromioclavicular ligaments; surgical technique

Resumen: Introducción: la luxación de la articulación acromioclavicular (AC) es una lesión frecuente que se observa en adultos jóvenes. El objetivo es describir una técnica quirúrgica que pueda restablecer la estabilidad horizontal y vertical de la articulación AC. Material y métodos: se describe una técnica quirúrgica utilizando un aloinjerto para la reconstrucción anatómica de los ligamentos coracoclaviculares (CC) y AC para luxaciones AC grado III-V de acuerdo con la clasificación de Rockwood. Resultados: es una técnica quirúrgica con reconstrucción anatómica y biológica de los ligamentos CC y AC con injerto. Se realizan dos túneles óseos en la clavícula pasando el cabo lateral del injerto por debajo del acromion; posteriormente se fijan los dos cabos con dos tornillos bioabsorbibles, restaurando de esta manera la estabilidad vertical y horizontal. Conclusión: este procedimiento permite restablecer la estabilidad vertical y horizontal de la articulación AC. Se requieren estudios de seguimiento para reportar resultados funcionales y radiológicos con el fin de poder asegurar ventajas en comparación con las técnicas existentes.

Abstract: Introduction: dislocation of the acromioclavicular (AC) joint is a common injury seen in young adults. The objective is to describe a surgical technique that can restore the horizontal and vertical stability of the AC joint. Material and methods: we describe a surgical technique that can restore horizontal and vertical stability using an allograft for the anatomical reconstruction of the CC and AC ligaments, for AC grade III-V dislocations according to the Rockwood classification. Results: this is a surgical technique with anatomical and biological reconstruction of the CC and AC ligaments, using an allograft. Two bone tunnels are made in the clavicle, passing the lateral end of the graft below the acromion; then the two ends are fixed with two bioabsorbable screws, restoring vertical and horizontal stability. Conclusion: this procedure allows to restore the vertical and horizontal stability of the AC joint. Follow up studies are required to report functional and radiological results, in order to ensure advantages compared to existing techniques.

Benefits and costs of immune memory in Rhodnius prolixus against Trypanosoma cruzi.

There is increasing evidence supporting the immune memory in invertebrates, but the studies are relatively neglected in insect vectors other than mosquitoes. Therefore, we tested two hypotheses: 1) Rhodnius prolixus insects possess immune memory against Trypanosoma cruzi, and 2) their immune memory is costly. The Dm28c and Y strains of T. cruzi were used, the former being more infective than the latter. On the one hand, the triatomines subjected to dual challenges with the Dm28c strain did not show significant differences in survival than those of the heterologous challenge groups control-Dm28c and Y-Dm28c. On the other hand, the insects survived longer after a dual Y-Y challenge than after the corresponding heterologous challenge (control-Y). The Y-Y, Dm28c-Y, and naïve groups showed similar survival. There was more prolonged survival following the Y-Y versus Dm28c-Dm28c dual challenge. The Dm28c-Dm28c group exhibited moulting sooner than the control-Dm28c or naïve group. In contrast, there were no differences in the probability of moulting between the Y-Y and naïve groups. The results suggest that triatomines have immune memory against the Y but not the Dm28c strain. Further investigation on triatomine and T. cruzi interaction is needed to determine if infectivity accelerates or delay growth due to innate immune memory.

The innate immune response of triatomines against Trypanosoma cruzi and Trypanosoma rangeli with an unresolved question: Do triatomines have immune memory?

The present work aimed to review the immune response from different triatomines against Trypanosoma cruzi and Trypanosoma rangeli and propose the study of immune memory in such insects. Trypanosoma use triatomines as vectors to reach and infect mammals. A key question to be answered about vector-parasite interaction is why the immune defense and resistance of the insect against the parasites vary. Up to date data shows that the defense of triatomines against parasites includes cellular (phagocytosis, nodulation and encapsulation) and humoral (antimicrobial peptides, phenoloxidase and reactive oxygen and nitrogen species) responses. The immune response varies depending on the triatomine species, the trypanosome strain and species, and the insect intestinal microbiota. Despite significant advances to understand parasite-insect interaction, it is still unknown if triatomines have immune memory against parasites and if this memory may derive from tolerance to parasites attack. Therefore, a closer study of such interaction could contribute and establish new proposals to control the parasite at the vector level to reduce parasite transmission to mammals, including men. For instance, if immune memory exists in the triatomines, it would be interesting to induce weak infections in insects to find out if subsequent infections are less intense and if the insects succeed in eliminating the parasites.

Oral and Palmitate Paliperidone Long-Acting Injectable Formulations' Use in Schizophrenia Spectrum Disorders: A Retrospective Cohort Study from the First Episode Psychosis Intervention Program (CRUPEP).

BACKGROUND: Long-acting injectable antipsychotics (LAIs) may be a suitable therapeutic option for those patients in earlier stages of psychosis to avoid relapses and disease progression. Despite that, there is a lack of evidence in the literature regarding the use of LAIs in this profile of patients. METHODS: This is a retrospective cohort analysis to assess the efficacy, tolerability, and pattern of use of palmitate paliperidone long-acting injectable (PPLAI) formulations (1- and 3-month doses) compared to oral paliperidone/risperidone in patients with a nonaffective first episode of psychosis (FEP) over 12 months of follow-up. Relevant sociodemographic and clinical information were assessed, as well as main clinical scales: Positive and Negative Syndrome Scale, Personal and Social Performance Scale, and Clinical Global Impression Scale Improvement and Severity measures. RESULTS: The study included 48 patients, 16 per arm, who were aged 20-50 years and had an FEP. Significant improvements were registered for all treatment groups. Despite that, patients receiving PPLAI 1- and 3-month formulations obtained greater improvements than those in the oral group in the main domains assessed (P < .001). We found no statistically significant differences in hospitalizations between groups. Side effects were presented in 24% of patients. A trend towards reducing antipsychotic doses was observed in 43.8% of patients to achieve the minimum effective dose and avoid the occurrence of side effects. CONCLUSIONS: To our knowledge, this is the first study assessing the use of palmitate paliperidone long-acting formulations versus oral risperidone or paliperidone in FEP. Treatment with PPLAI formulations seems to be an effective therapeutic choice at earlier stages of the disease.

Brain MRI without anesthesia in children less than 3 months old. / Resonancia magnética cerebral sin anestesia en niños menores de 3 meses.

INTRODUCTION: The use of general anesthesia in infants involves both short-term and long-term risks. The aim of this study is to evaluate the efficacy of brain MRI without anesthesia in infants younger than 3-month-old immobilized with a pillow. PATIENTS AND METHODS: This prospective case-control study was done in 2019. Cases were stable patients less than 3 months old who did not require ventilatory support for whom brain MRI was indicated. Patients were fed so they would fall asleep and placed in the scanner with an immobilizing pillow. Controls were clinically unstable patients matched for age and sex referred for brain MRI under general anesthesia. Three pediatric radiologists evaluated the success of the MRI study (whether it answered the clinical question), recorded whether it was necessary to repeat the study, and rated the presence of motion artifacts on a scale ranging from 1 to 4. RESULTS: A total of 47 cases were included (28 boys and 19 girls; mean age, 31 days). Of these, 42 (89%) MRI studies were considered successful. The proportion of successful MRI studies was lower in outpatients than in inpatients (p=0.02). The quality of MRI in cases was considered optimal in 60% and suboptimal (motion artifacts in one or two sequences) in 30%. No safety issues related with the technique were detected. The mean duration of the studies was 16.6minutes (range, 6-30minutes). All of the MRI studies in controls were considered successful; quality was considered optimal in 89% and suboptimal in 11%. In the first year in which we used this technique, we avoided the use of general anesthesia in 47 MRI studies in 42 newborns. CONCLUSION: Brain MRI using the feed and sleep technique in infants younger than 3-month-old immobilized with a pillow can be done safely and efficaciously without general anesthesia.

Hidden Costs in the Physiology of Argia anceps (Zigoptera: Coenagrionidae) due to Pollution.

Before a population becomes extinct, there are hidden costs in the physiology at the individual level that provide valuable insights into their condition. Here, we study two dams with one species in common (Argia anceps Garrison, 1996) to evaluate whether their physiological condition differed (total protein quantity, prophenoloxidase (proPO) and phenoloxidase (PO) activity, and protein carbonylation) during two consecutive years. The first dam, "El Gallinero" (contaminated, C), contains organic input from mines and agricultural activity, whereas the second, "Paso de Vaqueros" (non-contaminated, NC), is part of a biosphere reserve. Although at a phenological level, some physiological differences were observed (2012 vs 2013), individuals from the contaminated population had less total protein (2012, median = 1.815 µg/µL; 2013, 0.081 µg/µL) and more carbonylations in their proteins (2012, median = 19.00 nmol/mg; 2013, median = 121.69 nmol/mg) compared with the non-contaminated population (protein quantity in 2012, median = 3.716 µg/µL; 2013, median = 0.054 µg/µL; protein carbonylations in 2012, median = 0.00 nmol/mg; 2013, median = 99.44 nmol/mg). However, no significant differences were found in prophenoloxidase (C, median = 0.002 Vmax; NC, median = 0.002 Vmax) and phenoloxidase activity (C, median = 0.002 Vmax; NC, median = 0.001 Vmax). In addition, the biological oxygen demand (BOD) and Zn were more elevated in the C than NC population (C, BOD = 11.7, Zn = 0.17; NC, BOD = 8, Zn = 0.14). The results show that the impact of human activity can be observed not only through the extinction of species, but also at the physiological level of the individuals composing the populations through the evaluation of biomolecular damage, which can be observed at a much shorter scale compared with species extinction.

Depuración de lactato a gran altitud / Lactate clearance at high altitude

OBJETIVO: el estudio pretende caracterizar la depuración de lactato (DL) en pacientes críticamente enfermos, a gran altitud. DISEÑO: estudio prospectivo de cohorte. ÁMBITO: unidad de Cuidados Intensivos de Adultos del Hospital del Norte de la ciudad de El Alto, La Paz (Bolivia), a 4 150 metros sobre el nivel del mar, periodo 25 de abril 2016-01 de junio 2018. PACIENTES: todos los pacientes ingresados a la Unidad de Cuidados Intensivos de Adultos, nativos de gran altitud, así como residentes de la misma por lo menos los últimos 6 meses. RESULTADOS: se incluyeron 250 pacientes, con sobrevida de 68%, promedio de edad 50 años; en el grupo de 170 supervivientes, poco más de la cuarta parte del lactato de ingreso fue depurado (26%), a comparación del grupo de 80 fallecidos, en el cual incluso el valor de lactato se vio incrementado alrededor de la quinta parte del lactato de ingreso (21%), ambos con p ≤ 0.05 mediante el test de ANOVA. En pacientes críticamente enfermos a gran altitud, el riesgo relativo entre depuración de lactato ≥ 26% y sobrevida es de 2.7 con sensibilidad 0.72 y especificidad de 1. DISCUSIÓN Y CONCLUSIONES: la depuración de lactato en individuos críticamente enfermos nativos de gran altitud, se asocia a mayor sobrevida y debería ser considerado como un objetivo durante la reanimación en pacientes críticos, de forma similar a estudios realizados en otras latitudes

OBJECTIVE: to characterize the lactate clearance on critically ill patients, at high altitude. DESIGN: prospective cohort study. FIELD: critical Care Unit of "Hospital del Norte" in El Alto, La Paz (Bolivia), during the period April 25, 2016 ­ June 01, 2018. PARTICIPANTS: critically ill patients residents of high altitude at least the last 6 months, admitted to the Adult Critical Care Unit. RESULTS: 250 patients were included, with survival of 68%, age average of 50 years; in the 170 survivors, lactate clearance average was 26%, in contrast with 80 deceased patients who presented an increased lactate level of 25%, p ≤ 0.05, both of them through ANOVA test. In high landers critically ill patients, relative risk of lactate clearance ≥ 26% and survival was 2.7 with sensitivity 0.72 and specificity 1. DISCUSSION AND CONCLUSIONS: lactate clearance in critically ill high landers dwellers, is associated with survival and it should be considered also as a reanimation objective, comparable to other studies developed in different latitudes

[Tumor lysis syndrome in a pregnancy complicated with acute lymphoblastic leukemia]. / Síndrome de lisis tumoral en un embarazo complicado con leucemia linfoblástica aguda.

Acute leukemia is rare during pregnancy, affects about 1 in 75,000 pregnancies, of all leukemias diagnosed only 28% are acute lymphoblastic leukemia, this is a risk factor to develop spontaneous tumor lysis syndrome, it's a oncologic complication potentially deadly if the prophylactic treatment its avoided. Cases of acute lymphoblastic leukemia associated with pregnancy has been poorly documented in the literature the association of these two entities to pregnancy is the first report published worldwide, so the information is limited.

Temporal Variation in Immune Components of the White Grub Phyllophaga polyphylla (Bates) (Coleoptera: Melolonthidae).

Ecological immunology assumes that the host immune efficiency is correlated with its survival after pathogen challenge. To test this hypothesis, we challenged Phyllophaga polyphylla (Bates) larvae with the naturally occurring fungus Metarhizium pingshaense on two consecutive years (2011 and 2012). In each year, we injected the blastospores of M. pingshaense and then used levels of prophenoloxidase (proPO), phenoloxidase (PO) and total haemolymph serum protein as indicators of immune efficiency. Larvae were injected with (1) phosphate buffered saline (PBS) + Tween and viable blastospores of M. pingshaense, (2) PBS + Tween and non-viable blastospores of M. pingshaense, (3) PBS + Tween, or (4) non-manipulated. Overall, levels of PO, proPO and total haemolymph serum protein in larvae after 12 h were similar amongst treatments within each year of collection. However, larvae collected in 2011 showed higher PO and proPO activity but lower total haemolymph serum protein compared with larvae collected in 2012. A survival study injecting viable blastospores showed that larvae collected in both years died within 48 h; however, when non-viable blastospores were injected, which were still toxic to larvae, mortality was greater in larvae collected in 2011 compared with larvae collected in 2012. Altogether, these results indicate that PO, proPO and total haemolymph serum protein do not predict immune strength of P. polyphylla against blastospores of M. pingshaense, but higher values of PO and proPO were correlated with higher survival rates against non-infective but toxic agents. The possible role of some abiotic factors over the differences observed for immune components of P. polyphylla in different years of collection is discussed.

Nicotine increases GABAergic input on rat dorsal raphe serotonergic neurons through alpha7 nicotinic acetylcholine receptor.

The dorsal raphe nucleus (DRN) contains large populations of serotonergic (5-HT) neurons. This nucleus receives GABAergic inhibitory afferents from many brain areas and from DRN interneurons. Both GABAergic and 5-HT DRN neurons express functional nicotinic acetylcholine receptors (nAChRs). Previous studies have demonstrated that nicotine increases 5-HT release and 5-HT DRN neuron discharge rate by stimulating postsynaptic nAChRs and by increasing glutamate and norepinephrine release inside DRN. However, the influence of nicotine on the GABAergic input to 5-HT DRN neurons was poorly investigated. Therefore, the aim of this work was to determine the effect of nicotine on GABAergic spontaneous inhibitory postsynaptic currents (sIPSCs) of 5-HT DRN neurons and the subtype of nAChR(s) involved in this response. Experiments were performed in coronal slices obtained from young Wistar rats. GABAergic sIPSCs were recorded from post hoc-identified 5-HT DRN neurons with the whole cell voltage patch-clamp technique. Administration of nicotine (1 µM) increased sIPSC frequency in 72% of identified 5-HT DRN neurons. This effect was not reproduced by the α4ß2 nAChR agonist RJR-2403 and was not influenced by TTX (1 µM). It was mimicked by the selective agonist for α7 nAChR, PNU-282987, and exacerbated by the positive allosteric modulator of the same receptor, PNU-120596. The nicotine-induced increase in sIPSC frequency was independent on voltage-gated calcium channels and dependent on Ca(2+)-induced Ca(2+) release (CICR). These results demonstrate that nicotine increases the GABAergic input to most 5-HT DRN neurons, by activating α7 nAChRs and producing CICR in DRN GABAergic terminals.

Cost of immune priming within generations: trade-off between infection and reproduction.

Immune priming is a new paradigm in innate immunity. However, most studies have focused on the benefits of priming (enhanced survival and parasite clearance after a second challenge), while little attention has been paid to the costs. In this study, both factors were investigated in Anopheles albimanus primed against Plasmodium berghei. As previously observed in other invertebrates, compared to un-primed mosquitoes, those primed better controlled a challenge from the same parasite, and had a higher survival rate. Although there was no difference in the number of oviposited eggs between primed and control females, hatching rate was lower in primed than in control mosquitoes and it was more likely for control females to produce eggs than for primed females. Furthermore, a trade-off between parasite elimination and egg production was observed among primed mosquitoes, as primed females that successfully fought the infection were unable to produce eggs, but primed females that produced eggs were similarly infected as control un-primed ones. These results concord with recent mathematical models suggesting that reproduction affects immune priming outcomes, and may explain why in some species and under some conditions it seems that immune priming is not occurring.

Cross-cultural variation in women's preferences for cues to sex- and stress-hormones in the male face.

Women in the UK prefer the faces of men with low levels of the stress hormone cortisol, and the relationship is moderated by the sex hormone testosterone. In a Latvian sample, however, women's preferences were not affected by cortisol, and the interaction with testosterone differed from that of the UK. To further explore cross-cultural variation in preferences for facial cues to sex- and stress-hormones, we tested the preferences of women from 13 countries for facial composites constructed to differ in combinations of the hormones. We found significant relationships between a measure of societal development (the United Nations human development index 2011) and preferences for cues to testosterone in the face, and the interaction between preferences for cues to testosterone and cortisol. We also found a significant relationship between preferences for cues to testosterone and a societal-level measure of parasite stress. We conclude that societal-level ecological factors influence the relative value of traits revealed by combinations of sex- and stress-hormones.