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We aimed to evaluate the accuracy of Interferon-tau stimulated genes (ISG) abundance in peripheral blood polymorphonuclear cells (PMNs) on D20 after fixed-time artificial insemination (FTAI; D0) as a pregnancy diagnosis method against CL evaluation by Doppler ultrasonography and progesterone (P4) concentrations on D20, as well as Pregnancy Associated Glycoproteins (PAG) concentrations on D25. Additionally, we evaluated the potential of ISG abundance in PMNs as pregnancy loss predictors. Nelore heifers (n = 103) and cows (n = 144) underwent estrous synchronization and were artificially inseminated on D0. Pregnancy was diagnosed by B-mode ultrasonography on D30 and D70, and after the final diagnosis, females were classified in four groups: Pregnant; Non-pregnant; Functional CL on D20 but non-pregnant (CL-NP) and Pregnancy loss between D30 and D70 (PL). After determining cutoff values, the Sensitivity (SE), Specificity (SP), Positive Predictive Value (PPV), Negative Predictive Value (NPV) and Accuracy (ACC) were determined for each method. All methods were classified as significant (P < 0.05) predictors of pregnancy. Both ISG expression and PAG concentrations were greater (P < 0.05) in pregnant females than in non-pregnant and CL-NP females but did not differ (P > 0.05) from the PL group. ISG15 expression was greater (P < 0.05) in heifers than in cows, but this difference was not found in OAS1 expression and PAG concentrations. All the methods evaluated were proven to be adequate predictors of pregnancy, but greater accuracies were obtained through PAG concentrations and Doppler-US, due to the decreased number of false positive and false negative results.

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Painful conditions and sleep disturbances are major public health problems worldwide and one directly affects the other. Sleep loss increases pain prevalence and severity; while pain disturbs sleep. However, the underlying mechanisms are largely unknown. Here we asked whether chronic sleep restriction for 6 h daily progressively increases pain sensitivity and if this increase is reversed after two days of free sleep. Also, whether the pronociceptive effect of chronic sleep restriction depends on the periaqueductal grey and on the nucleus accumbens, two key regions involved in the modulation of pain and sleep-wake cycle. We showed that sleep restriction induces a pronociceptive effect characterized by a significant decrease in the mechanical paw withdrawal threshold in rats. Such effect increases progressively from day 3 to day 12 remaining stable thereafter until day 26. Two consecutive days of free sleep were not enough to reverse the effect, not even to attenuate it. This pronociceptive effect depends on the periaqueductal grey and on the nucleus accumbens, since it was prevented by their excitotoxic lesion. Complementarily, chronic sleep restriction significantly increased c-Fos protein expression within the periaqueductal grey and the nucleus accumbens and this correlates with the intensity of the pronociceptive effect, suggesting that the greater the neural activity in this regions, the greater the effect. These findings may contribute not only to understand why painful conditions are more prevalent and severe among people who sleep poorly, but also to develop therapeutic strategies to prevent this, increasing the effectiveness of pain management in this population.

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Generalised tonic and tonic-clonic seizures are followed by significant increase in nociceptive thresholds in both laboratory animals and humans. The endogenous opioid peptides play a role in antinociceptive signalling, and the periaqueductal grey matter (PAG) is recruited to induce analgesia. Thus, the aim of this investigation was to evaluate the role of µ1 -opioid receptors in the dorsomedial (dm) and ventrolateral (vl) columns of PAG in post-ictal antinociception. Pentylenetetrazole (PTZ; 64 mg/kg), which is an ionotropic GABA-mediated Cl- influx antagonist, was intraperitoneally (IP) administered to induce tonic-clonic seizures in Wistar rats. The tail-flick test was used to measure the nociceptive threshold. Microinjections of naltrexone (5.0 µg/0.2 µL), which is a non-selective opioid receptor antagonist, in both dmPAG and vlPAG decreased the tonic-clonic seizure-induced antinociception in seizing animals from 10 to 120 min after seizures. Furthermore, microinjections of the µ1 -opioid receptor-selective antagonist naloxonazine (5.0 µg/0.2 µL) into the dmPAG decreased post-ictal antinociception immediately after convulsive reactions and from 10 to 90 min after seizures. However, vlPAG-pretreatment with naloxonazine at the same concentration decreased the post-ictal antinociception 30 min after the onset of tonic-clonic seizures and the nociceptive threshold returned to basal values 120 min after seizures. These findings indicate that µ1 -opioid receptor-signalling mechanisms in both dmPAG and vlPAG play a relevant role in the organisation of post-ictal antinociception. In addition, µ1 -opioid receptors in the dmPAG rather than in vlPAG seem to be more critically recruited during the antinociception induced by generalised tonic-clonic seizures.

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Galanin is a peptide that is present in the central nervous system in mammals, including rodents and humans. The actions of galanin are mediated by three types of metabotropic receptors: GAL1, GAL2, and GAL3. GAL1 and GAL3 increase K(+) efflux, and GAL2 increases intracellular Ca(2+) levels. The distribution of galanin and its receptors suggests its involvement in fear and/or anxiety. The periaqueductal gray matter (PAG) is a key mediator of defensive behaviors that is both targeted by galaninergic projections and supplied with GAL1 receptors and, less markedly, GAL2 receptors. We examined the effects of galanin microinjections in the dorsal PAG (dPAG) on the performance of rats in different models of anxiety. Male Wistar rats (n=7-12) were implanted with guide cannulae in the dPAG. They received microinjections of either galanin (0.3, 1.0, and 3.0 nmol) or vehicle and were tested in the Vogel conflict test (VCT), elevated plus maze (EPM), and elevated T-maze (ETM). Rats that were tested in the ETM were further evaluated for exploratory activity in the open field test (OFT). Galanin microinjections had no effects on anxiety-like behavior in the EPM or VCT or exploratory activity in the EPM or OFT. In the ETM, however, microinjections of 3 nmol galanin impaired learned anxiety (i.e., avoidance of the open arms) without changing unconditioned fear (i.e., escape from the open arms). The present data suggest that galanin transmission in the dPAG inhibits the acquisition of anxiety-like responses in the ETM.

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There are multiple challenges to teaching in the clinical setting. The One Minute Preceptor is a learner-centered model for effective and efficient teaching in a clinical setting that can help to overcome these challenges. It consists of 5 microskills: get a commitment; probe for supporting evidence; teach general rules; reinforce what was right; correct mistakes. This article illustrates with case vignettes the use of these microskills for the busy Pediatric and Adolescent Gynecology clinician.

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The rat retrotrapezoid nucleus (RTN) contains neurons that have a well-defined phenotype characterized by the presence of vesicular glutamate transporter 2 (VGLUT2) mRNA and a paired-like homeobox 2b (Phox2b)-immunoreactive (ir) nucleus and the absence of tyrosine hydroxylase (TH). These neurons are important to chemoreception. In the present study, we tested the hypothesis that the chemically-coded RTN neurons (ccRTN) (Phox2b(+)/TH(-)) are activated during an acute episode of running exercise. Since most RTN neurons are excited by the activation of perifornical and lateral hypothalamus (PeF/LH), a region that regulates breathing during exercise, we also tested the hypothesis that PeF/LH projections to RTN neurons contribute to their activation during acute exercise. In adult male Wistar rats that underwent an acute episode of treadmill exercise, there was a significant increase in c-Fos immunoreactive (c-Fos-ir) in PeF/LH neurons and RTN neurons that were Phox2b(+)TH(-) (p<0.05) compared to rats that did not exercise. Also the retrograde tracer Fluoro-Gold that was injected into RTN was detected in c-Fos-ir PeF/LH (p<0.05). In summary, the ccRTN neurons (Phox2b(+)TH(-)) are excited by running exercise. Thus, ccRTN neurons may contribute to both the chemical drive to breath and the feed-forward control of breathing associated with exercise.

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The present work was aimed to evaluate the contribution of interoception to the autonomic and behavioral responses to hypoxia. To address this issue, we studied whether the inactivation of the primary interoceptive posterior insular cortex (pIC) may disrupt the autonomic and behavioral effects of hypoxia in conscious rats. Rats were implanted with telemetric transmitters and microinjection cannulae placed bilaterally in the pIC. After one week, rats were injected with bupivacaine (26.5µM 1µL/side) and saline (1µL/side) into the pIC, and exposed to hypoxia (∼6% O2) for 150s, and autonomic and behavioral responses were recorded. Hypoxia produces hypertension, tachycardia followed by bradycardia, and hypothermia. When O2 dropped to ∼8%, rats showed escape behavior. Baseline cardiovascular variables and the pattern of hypoxia-induced autonomic and behavioral responses were not disrupted by pIC inactivation. However, pIC inactivation produced a modest but significant temperature decrease, higher bradycardic and hypertensive responses to hypoxia, and a minimal delay in escape onset. In addition, we measured the hypoxia-induced Fos activation in the nucleus tractus solitarius (NTS), the periaqueductal gray matter (PAG) and the pIC, which are key components of the interoceptive pathway. Hypoxia increased the number of Fos-positive neurons in the NTS and PAG, but not in the pIC. Present results suggest that pIC is not involved in the hypoxia-induced behavioral response, which seems to be processed in the NTS and PAG, but has a role in the efferent control of autonomic changes coping with hypoxia.

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As glicoproteínas associadas à prenhez são substâncias expressas na placenta de mamíferos ungulados. Em ruminantes, essas proteínas são secretadas continuamente desde a implantação embrionária até o parto. Recentemente, estas proteínas tem sido correlacionadas e utilizadas para o diagnostico precoce da gestação em bovinos. Assim, objetivou-se com este estudo avaliar um teste ELISA-PAG que utiliza a detecção de glicoproteínas para o diagnóstico precoce de gestação em vacas zebuínas de corte, determiando a acurácia do método aos 25 e 28 dias após inseminação artificial em tempo fixo, comparando-o com a utilização da ultrassonografia no mesmo período. O estudo foi conduzido em uma fazenda situada na mesorregião do Nordeste Paraense, no qual se utilizou 130 fêmeas mestiças da raça Nelore (Bos taurus indicus), saudáveis e submetidas a um protocolo hormonal para inseminação artificial em tempo fixo. Ao 25º e 28º dia pós-inseminação, foram realizados exames ultrassonográficos e colheitas de sangue para determinação das glicoproteínas associadas à prenhez. As amostras de sangue foram centrifugadas, e os soros sanguíneos foram aliquotados e acondicionados a -20 °C para posterior determinação das glicoproteínas associadas à prenhez, utilizando um ELISA comercial conforme orientações do fabricante. Os testes foram realizados no Laboratório de Virologia da Seção de Meio Ambiente do Instituto Evandro Chagas. Os resultados da densidade óptica de leitura foram usados para validar o teste em que as amostras com resultados ? 0.300 foram consideradas positivas (prenhe) e aquelas com resultados ? 0.300, negativas (não prenhe). Também foi feita avaliação visual da placa pela cor (poços com solução amarela, positivo; poços com solução translúcida, negativo). Os resultados verificados foram classificados como diagnóstico positivo correto (a), diagnóstico positivo incorreto (b), diagnóstico negativo correto (c), diagnóstico negativo incorreto (d). A partir desses valores foram calculados de cada método a sensibilidade (100 x a/a + d), a especificidade (100 x c/c + b), o valor preditivo positivo (100 x a/a + b) e o valor preditivo negativo (100 x c/c + d). O teste do Qui-quadrado foi utilizado para comparar as sensibilidades e especificidades dos dois métodos de diagnóstico de gestação (ELISA-PAG e ultrassonografia). Diferenças entre vacas prenhes e não prenhes para o ELISA-PAG foram analisadas usando o test-t Student’s. A acurácia do ELISA-PAG foi igual ao 25º e 28º dia pós-inseminação, com sensibilidade de 100%, especificidade 92,86%, valor preditivo positivo 96,70% e valor preditivo negativo 100%. Todavia, a ultrassonografia aos 25º e 28º dias, respectivamente, apresentou sensibilidades de 62,50% e 93,18% (p < 0,05), especificidades de 95,24% e 95,24%, valores preditivos positivos de 96,49% e 97,63%, e valores preditivos negativos de 54,79% e 86,96% (p < 0,05). Houve diferenças significativas entre o ELISA-PAG e ultrassonografia em realção as sensibilidades e valores preditivos negativos, porém os exames foram equivalentes em especificidades e valores preditivos positivos. Conclui-se que o teste ELISA-PAG demonstrou-se mais sensível e tão específico quanto à ultrassonografia no período estudado, com alta precisão especialmente na identificação de fêmeas não gestantes, podendo ser utilizado com segurança a partir do 25º dia após a IATF para obtenção precoce do diagnóstico de prenhez em fêmeas zebuínas

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It is well established that morphine inhibits maternal behaviors. Previous studies by our group have shown activation of the rostrolateral periaqueductal gray (rlPAG) upon inhibition-intended subcutaneous injections of morphine. In this context, we demonstrated that a single naloxone infusion into the rlPAG, following this opioid-induced inhibition, reactivated maternal behaviors. Since these data were obtained by using peripheral morphine injections, the present study was designed to test whether morphine injected directly into the rlPAG would affect maternal behaviors. Our hypothesis that morphine acting through the rlPAG would disrupt maternal behaviors was confirmed with a local infusion of morphine. The mothers showed shorter latency for locomotor behavior to explore the home cage (P = 0.049). Inhibition was especially evident regarding retrieving (P = 0.002), nest building (P = 0.05) and full maternal behavior (P = 0.023). These results support the view that opioidergic transmission plays a behaviorally meaningful inhibitory role in the rostrolateral PAG.

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Glutamate N-methyl-D-aspartate (NMDA) receptor activation within the dorsal column of the periaqueductal gray (dPAG) leads to antinociceptive, autonomic, and behavioral responses characterized as the fear reaction. Activation of NMDA receptors in the brain increases nitric oxide (NO) synthesis, and NO has been proposed to be a mediator of the aversive action of glutamate. This paper reviews a series of studies investigating the effects of neuronal NO synthase (nNOS) inhibition in the dPAG of mice in different aversive conditions. nNOS inhibition by infusion of Nù-propyl-L-arginine (NPLA) prevents fear-like reactions (e.g., jumping, running, freezing) induced by NMDA receptor stimulation within the dPAG and produces anti-aversive effects when injected into the same midbrain site in mice confronted with a predator. Interestingly, nNOS inhibition within the dPAG does not change anxiety-like behavior in mice exposed to the elevated plus maze (EPM), but it reverses the effect of an anxiogenic dose of NMDA injected into the same site in animals subjected to the EPM. Altogether, the results support a role for glutamate NMDA receptors and NO in the dPAG in the regulation of defensive behaviors in mice. However, dPAG nitrergic modulation of anxiety-like behavior appears to depend on the magnitude of the aversive stimulus.(AU)

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Glutamate N-methyl-D-aspartate (NMDA) receptor activation within the dorsal column of the periaqueductal gray (dPAG) leads to antinociceptive, autonomic, and behavioral responses characterized as the fear reaction. Activation of NMDA receptors in the brain increases nitric oxide (NO) synthesis, and NO has been proposed to be a mediator of the aversive action of glutamate. This paper reviews a series of studies investigating the effects of neuronal NO synthase (nNOS) inhibition in the dPAG of mice in different aversive conditions. nNOS inhibition by infusion of Nω-propyl-L-arginine (NPLA) prevents fear-like reactions (e.g., jumping, running, freezing) induced by NMDA receptor stimulation within the dPAG and produces anti-aversive effects when injected into the same midbrain site in mice confronted with a predator. Interestingly, nNOS inhibition within the dPAG does not change anxiety-like behavior in mice exposed to the elevated plus maze (EPM), but it reverses the effect of an anxiogenic dose of NMDA injected into the same site in animals subjected to the EPM. Altogether, the results support a role for glutamate NMDA receptors and NO in the dPAG in the regulation of defensive behaviors in mice. However, dPAG nitrergic modulation of anxiety-like behavior appears to depend on the magnitude of the aversive stimulus.

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Nonsteroidal anti-inflammatory drugs (NSAIDs) act upon peripheral tissues and upon the central nervous system to produce analgesia. A major central target of NSAIDs is the descending pain control system. The rostral structures of the descending pain control system send impulses towards the spinal cord and regulate the transmission of pain messages. Key structures of the descending pain control system are the periaqueductal gray matter (PAG) and the rostral ventromedial region of the medulla (RVM), both of which are critical targets for endogenous opioids and opiate pharmaceuticals. NSAIDs also act upon PAG and RVM to produce analgesia and, if repeatedly administered, induce tolerance to themselves and cross-tolerance to opioids. Experimental evidence shows that this is due to an interaction of NSAIDs with endogenous opioids along the descending pain control system. Analgesia by NSAIDs along the descending pain control system also requires an activation of the CB1 endocannabinoid receptor. Several experimental approaches suggest that opioids, NSAIDs and cannabinoids in PAG and RVM cooperate to decrease GABAergic inhibition and thus enhance the descending flow of impulses that inhibit pain.

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La pancreatitis aguda, especialmente en su forma grave, está asociada con una respuesta inflamatoria sistémica que lleva a un estado de hipermetabolismo e hipercatabolismo, en el que se requiere un excelente soporte nutricional que permita mantener la integridad estructural y la función de los órganos vitales con un estímulo mínimo de la secreción pancreática.La nutrición parenteral total era el soporte de elección, que permitía obtener todos los beneficios de la nutrición temprana sin estimular la secreción pancreática; pero la evidencia actual muestra mayores beneficios con la nutrición enteral, porque se asocia con menos complicaciones infecciosas y metabólicas y con disminución en los costos. Por ello las guías actuales de tratamiento de la pancreatitis aguda grave recomiendan como primera elección el soporte nutricional enteral.

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