Inhibition of long-term potentiation by CuZn superoxide dismutase injection in rat dentate gyrus: involvement of muscarinic M1 receptor.

Long-term potentiation (LTP) and long-term depression represent important processes that modulate synaptic transmission that carries out a key role in neural mechanisms of memory. Many studies give strong evidences on a role of the reactive oxygen species in the induction of LTP in CA1 region of hippocampal slices that was inhibited by adding the scavenger enzyme superoxide dismutase (SOD1). Previous data showed that SOD1 is secreted by many cellular lines, including neuroblastoma SK-N-BE cells through microvesicles by an ATP-dependent mechanism; moreover, it has been shown that SOD1 interacts with human neuroblastoma cell membranes increasing intracellular calcium levels via a phospholipase C-protein kinase C pathway activation. The aim of this study was to investigate the effect of intracerebral injection of SOD1 or the inactive form of enzyme (ApoSOD) on the modulation of synaptic transmission in dentate gyrus of the hippocampus in urethane anesthetized rats. The results of the present research showed that intracerebral injection of SOD1 and ApoSOD in the dentate gyrus of the rat hippocampal formation inhibits LTP induced by high-frequency stimulation of the perforant path. This result cannot be only explained by the dismutation of oxygen radical induced by SOD1 since also ApoSOD, that lacks the enzymatic activity, carries out the same inhibitory effect on LTP induction.

What is the effectiveness of surgical and non-surgical therapies in the treatment of ischemic priapism in patients with sickle cell disease? A systematic review by the EAU Sexual and Reproductive Health Guidelines Panel.

Sickle cell disease (SCD) is an inherited hemoglobin disorder characterized by the occlusion of small blood vessels by sickle-shaped red blood cells. SCD is associated with a number of complications, including ischemic priapism. While SCD accounts for at least one-third of all priapism cases, no definitive treatment strategy has been established to specifically treat patients with SC priapism. The aim of this systematic review was to assess the efficacy and safety of contemporary treatment modalities for acute and stuttering ischemic priapism associated with SCD. The primary outcome measures were defined as resolution of acute priapism (detumescence) and complete response of stuttering priapism, while the primary harm outcome was as sexual dysfunction. The protocol for the review has been registered (PROSPERO Nr: CRD42020182001), and a systematic search of Medline, Embase, and Cochrane controlled trials databases was performed. Three trials with 41 observational studies met the criteria for inclusion in this review. None of the trials assessed detumescence, as a primary outcome. All of the trials reported a complete response of stuttering priapism; however, the certainty of the evidence was low. It is clear that assessing the effectiveness of specific interventions for priapism in SCD, well-designed, adequately-powered, multicenter trials are strongly required.

Proficient manipulation of fibreoptic bronchoscope to carina by novices on first clinical attempt after specialized bench practice.

BACKGROUND: Proficient manipulation of the fibreoptic bronchoscope is an important component of competent bronchoscopic airway management. We studied the duration of specialized bench training necessary to achieve this proficiency and the subsequent transfer of this psychomotor skill to human subjects. METHODS: Twenty-nine novice endoscopists undertook the training associated with a commercial non-anatomic endoscopic dexterity training system, Dexter. Bronchoscopic driving performance was assessed after each hour of self-directed training, using a global rating scale from 1 (unskilled) to 5 (expert) with a score of 3 linked to proficiency. The scale was applied to anonymized recordings of the endoscopic view as the bronchoscope was manipulated from the mouth to the carina of an anatomic manikin. Once bench proficiency was achieved, the ability of participants to perform the skill on volunteer co-participants was assessed. RESULTS: Ninety-six per cent of participants achieved proficiency on the manikin within 4 h of practice. Ninety-three per cent then drove the bronchoscope proficiently from the mouth to the carina of clinical volunteers on the first attempt. CONCLUSIONS: The endoscopic dexterity required to proficiently drive a bronchoscope in human subjects to an anatomic endpoint relevant to fibreoptic intubation is achievable after 2-4 h of specialized bench training. Training in the local environment may be more conducive to success than in time-limited workshops. Achieving a defined proficiency standard on bench models contributes to the development of basic bronchoscopic competence. This has the potential to protect patients from novice learning curves, optimize clinical education and efficiency, and assist compliance with difficult airway algorithms.

5HT expression in the stomach and duodenum of the Rhesus Monkey (Macaca mulatta).

This study aims to provide a histological description of different regions of the gastric and duodenal mucosa in Rhesus monkey, as well as to analyze the distribution and the relative frequency of 5-HT. The cardia region mucosa consists of simple columnar epithelium PAS + and AB + and the 5-HT cells were observed at the base of the gland (QA [5-HT cells]/mm²) = 8.72 ±â€¯4.98). The body region, has a smaller number of glands. The 5-HT cells were found predominant in the base of the gastric glands. QA= 6.96 ±â€¯3.81. When compared to body region, the stomach fundus has smaller gastric pits. The 5-HT cells are found at the base of the glands near the main cells. QA = 5.29 ±â€¯2.09. The pylorus region was found to have deep pits and well-developed gastric glands. The 5-HT cells are scarce, at the base of the pyloric gland. QA = 1.18 ±â€¯1.36. The duodenum presented goblet cells strong PAS + and AB +. 5-HT cells were found both in the lining epithelium and in the intestinal glands. QA = 8.16 ±â€¯2.59.

Inhibition of prostaglandin synthesis reduces the induction of MyoD expression in rat soleus muscle.

MyoD is a myogenic regulatory factor with a critical role in skeletal muscle development and regeneration. As muscle regeneration comes with an inflammatory process, it has been proposed that the inflammatory cells can play an important role in the induction of muscle fibres regeneration. The aim of the present work was to verify if a cyclooxygenase inhibitory drug (ketoprofen) would alter the normal expression of MyoD in a regenerating rat soleus muscle after an over-load lesion. Using immunohistochemical techniques, the numbers of m-cadherin-positive cells, a selective marker of satellite cells, and MyoD-positive cells were evaluated in functionally overloaded rat soleus muscles 4 days after a gastrocnemius tendon cut. The same study was conducted either with four rats injected with ketoprofen (100 mg/kg b.w./day) or with four rats injected with saline solution. The data obtained showed a very large decrease in the number of MyoD positive/m-cadherin positive cells in the ketoprofen injected group compared to the control group. Although further studies are needed to elucidate the sequence of biochemical events that induce a reduction of MyoD expression due to ketoprofen, the results demonstrate that prostaglandin synthesis is required for the induction of MyoD expression and that ketoprofen can affect this expression, with possible adverse effects on muscle regeneration.

Espresso coffee increases parasympathetic activity in young, healthy people.

Caffeine induces modifications of activity of the autonomic nervous system. This study analyzed the effect of a cup of espresso coffee on the heart rate variability (HRV) power spectral analysis, which is a method providing evaluation of the sympathetic and parasympathetic discharge. In young, healthy sedentary subjects (10 male, 10 female; aged 25-30 years), the HRV-power spectrum was evaluated over a period of 150 min after the administration of espresso coffee (caffeine, 75 mg) or decaffeinated coffee (caffeine, < 18 mg) in supine and seated position. Absolute values of the spectrum were summed in low (LF) and high frequencies (HF). The LF and HF spectra were used to estimate the sympathetic and parasympathetic activity, respectively. In the supine position, coffee increases HF, while decaffeinated coffee causes little modifications of HF. In the seated position, HF is not modified by coffee or decaffeinated coffee. Coffee and decaffeinated coffee do not induce any modification of LF in both positions. This experiment indicates that espresso coffee influences parasympathetic activity in the supine position.

Cortical spreading depression induces the expression of iNOS, HIF-1alpha, and LDH-A.

The mechanisms of tolerance to subsequent episodes of ischemia induced by cortical spreading depression (CSD) are not clear. The effects of CSD on the expression of inducible nitric oxide synthase (iNOS), hypoxia inducible factor-1alpha (HIF-1alpha), and lactate dehydrogenase-A (LDH-A) were evaluated in the present experiment. Unilateral CSD was induced in Sprague-Dawley rats by application of KCl on the right cortex and the mRNA levels of iNOS, HIF-1alpha, and LDH-A were evaluated at 15 min, 2 h, 4 h, 6 h or 24 h after CSD. RT-PCR analysis showed: 1) an increase of iNOS mRNA at 15 min, 2 h, 4 h; 2) an increase of HIF-1alpha mRNA at 6 h; 3) an increase of LDH-A mRNA at 4 h. In situ hybridization with specific digoxigenin-labeled oligonucleotides revealed that the mRNA levels were increased at 15 min-2 h for iNOS, 2-4 h for LDH-A and 6 h for HIF-1 after CSD. Immunohistochemistry analysis revealed that levels of iNOS and HIF-1alpha were increased, respectively, at 2 h and 6 h after CSD. These data suggest that CSD promotes the expression of iNOS, HIF-1alpha, and LDH-A in nervous cells giving a neuroprotective effect.

The synthesis of azadirachtin: a potent insect antifeedant.

We describe in full the first synthesis of the potent insect antifeedant azadirachtin through a highly convergent approach. An O-alkylation reaction is used to unite decalin ketone and propargylic mesylate fragments, after which a Claisen rearrangement constructs the central C8-C14 bond in a stereoselective fashion. The allene which results from this sequence then enables a second critical carbon-carbon bond forming event whereby the [3.2.1] bicyclic system, present in the natural product, is generated via a 5-exo-radical cyclisation process. Finally, using knowledge gained through our early studies into the reactivity of the natural product, a series of carefully designed steps completes the synthesis of this challenging molecule.

Intracerebroventricular injection of oxidant and antioxidant molecules affects long-term potentiation in urethane anaesthetized rats.

Production of superoxide anions in the incubation medium of hippocampal slices can induce long-term potentiation (LTP). Other reactive oxygen species (ROS) such as hydrogen peroxide are able to modulate LTP and are likely to be involved in aging mechanisms. The present study explored whether intracerebro-ventricular (ICV) injection of oxidant or antioxidant molecules could affect LTP in vivo. With this aim in mind, field excitatory post-synaptic potentials (fEPSPs) elicited by stimulation of the perforant pathway were recorded in the dentate gyrus of the hippocampal formation in urethane-anesthetized rats. N-acetyl-L-cysteine, hydrogen peroxide (H2O2) or hypoxanthine/xanthine-oxidase solution (a superoxide producing system) were administrated by ICV injection. The control was represented by a group injected with saline ICV. Ten minutes after the injection, LTP was induced in the granule cells of the dentate gyrus by high frequency stimulation of the perforant pathway. Neither the H(2)O(2) injection or the N-acetyl-L-cysteine injection caused any variation in the fEPSP at the 10-min post-injection time point, whereas the superoxide generating system caused a significant increase in the fEPSP. Moreover, at 60 min after tetanic stimulation, all treatments attenuated LTP compared with the control group. These results show that ICV administration of oxidant or antioxidant molecules can modulate LTP in vivo in the dentate gyrus. Particularly, a superoxide producing system can induce potentiation of the synaptic response. Interestingly, ICV injection of oxidants or antioxidants prevented a full expression of LTP compared to the saline injection.

Efficacy of Modern Light Curing Units in Polymerizing Peripheral Zones in Simulated Large Bulk-fill Resin-composite Fillings.

The variation in micro-hardness (HV) within simulated large cavities (10 × 6 mm) filled in one increment with three bulk-fill resin-based composites (BF-RBC) was assessed by means of a universal hardness device. Modern blue and violet-blue light curing units (LCUs) were applied in three different positions, by rotating the LCU in 120° steps. The exposure distance was 3 mm. One center and two peripheral (4-mm apart from the center) HV line profiles were measured in 0.5-mm steps at 24 hours postpolymerization to calculate the depth of cure (DOC). Incident light, irradiance, and spectral distribution were recorded. A multivariate analysis (general linear model) assessed the effect of the varied parameters as well as their interaction terms on HV and DOC. The effect of LCU rotation was not significant ( p=0.109). The DOC varied between 3.46 mm and 5.50 mm and was more strongly influenced by the BF-RBC ( p<0.001, ηP2=0.774), followed by the width of specimen ( p<0.001, ηP2=0.554), while the influence of the LCU was very low ( p<0.06, ηP2=0.070). Whether a BF-RBC filling is cured as well in the periphery as in the center depends more on the material than on the curing unit used.

Cortical control of neurally-mediated arrhythmogenic properties of desacetyl lanatoside C: the role of the posterior hypothalamus.

Functional ablation of the cerebral cortex by cortical spreading depression (CSD) significantly increased the dose of desacetyl lanatoside C required to induce A-V block and ventricular fibrillation. To examine the role of the posterior hypothalamus in the increased resistance of decorticated rats to arrhythmia induced by toxic doses of desacetyl lanatoside C, four groups of animals were injected with this drug: group 1 rats had a craniotomy; group 2 rats had a craniotomy and functional decortication; group 3 rats had a craniotomy and a hypothalamic lesion; and group 4 rats had a craniotomy, hypothalamic lesion and functional decortication. The dose of drug required to induce A-V block and ventricular fibrillation was significantly less in group 1, than in groups 2,3 and 4, and there was no statistically significant difference between these last three groups. These results are consistent with the hypothesis that the increased resistance to arrhythmia induced by desacetyl lanatoside C in decorticated rats is mediated by the posterior hypothalamus.

Nociceptive stimulation induces glutamate receptor down-regulation in the trigeminal nucleus.

The dorsal horn of the subnucleus caudalis of the spinal trigeminal nucleus is a relay of oro-facial pain transmission; increase in subnucleus caudalis neuronal activity in response to tissue injury affects the level of chemical mediators participating in nociceptive processing. We investigated, by means of immunocytochemistry, the expression of N-methyl-D-aspartate and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) glutamate receptor subunits in this nucleus in a model of inflammation. Rats injected with formalin in the whisker pad were compared with saline-injected control rats. One and two days after formalin injection, the immunostaining of cell bodies and neuropil of the AMPA receptor subunits GluR1 and GluR2/3 was markedly decreased in the ipsilateral superficial laminae of the subnucleus caudalis compared to the contralateral side. Side differences were not evident in the saline-treated animals. The down-regulation of AMPA GluR1 and GluR2/3 was no longer detectable in the subnucleus caudalis three days after formalin injection. No side difference was detected in the N-methyl-D-aspartate receptor subunit NR2A/B immunoreactivity of the subnucleus caudalis at any time-point in the formalin-injected animals. The modulation of AMPA receptor may be related to the decrease of hyperalgesia evident 1 h after formalin injection, in spite of the increasing perioral inflammation evident later on and characteristic of the formalin model. The present findings point out a selective down-regulation of AMPA receptor subunits in the transduction of trigeminal pain. These data also support the involvement of glutamate receptor subunits in the processing of trigeminal inflammation induced by noxious chemical stimulation.

Phase II double-blind randomized study of lonidamine and radiotherapy in epidermoid carcinoma of the lung.

Patients with non metastatic squamous cell lung cancer were treated with radiotherapy (RT) plus lonidamine (LND) or placebo (PLAC), according to a randomized double-blind study design. Treatment with lonidamine 150 mg t.i.d. (27 patients) or placebo (23 patients) started 3 days before RT, lasted up to 7 months. Partial responses were observed in 14 and 6 patients respectively in the LND + RT and PLAC + RT groups. Statistical analysis of the survival curves showed no significant difference between the LND + RT (median 311 days) and PLAC + RT (median 193 days) groups. Stage III patients survived significantly longer (p less than 0.05) when treated with LND + RT (median 318 days) than with PLAC + RT (median 163 days). No synergistic toxic effects between radiation and LND were noted. To confirm these data a new and larger multicentric study is now in progress.

Expression of the retinoblastoma-related p107 and Rb2/p130 genes in human placenta: an immunohistochemical study.

It has been proposed that tumor suppressor genes may have a role in the mechanisms of proliferation and differentiation during human placental development. The Retinoblastoma gene family is a well known family of tumor suppressor genes. Many studies have pointed out a role of this family not only in cell cycle progression, but also during development and differentiation. On the light of these observations we have investigated the immunohistochemical expression pattern of the Retinoblastoma family members, p107 and Rb2/p130 in human placenta samples in first trimester and full-term placental sections. p107 and pRb2/p130 showed the most abundant expression levels during the first trimester of gestation and progressively declined to being barely detectable in the placenta by late gestation. These results indicate that the expression of the above genes is modulated during placental development and suggest a mechanism for controlling trophoblast proliferation.

Highly selective entry to the azadirachtin skeleton via a Claisen rearrangement/radical cyclization sequence.

[formula: see text] A highly diastereoselective, microwave-induced Claisen rearrangement of an appropriately substituted propargylic enol ether allows the formation of the sterically congested C8-C14 bond of azadirachtin. When combined with a radical-mediated cyclization of the corresponding allene, this sequence offers rapid entry to the framework of azadirachtin.

Posterior hypothalamic activity and cortical control during the PGE1 hyperthermia.

The firing rate of the posterior hypothalamic neurones and interscapular brown adipose tissue and colonic temperatures (TIBAT and TC) were monitored in 36 urethane-anaesthetized male Sprague-Dawley rats before and after an intracerebroventricular (i.c.v.) injection of 400 ng prostaglandin E1 (PGE1) or saline. The i.c.v. injection was preceded by functional decortication in half of each group. The results show an increase of firing rate, TIBAT and TC after PGE1 injection in the rats without decortication. Functional decortication significantly reduced these enhancements. These findings demonstrate that the posterior hypothalamus plays a significant role in the hyperthermia induced by PGE1 and that the cerebral cortex is involved in the control of posterior hypothalamic activity.

Nitric oxide reduces the thermogenic changes induced by lateral hypothalamic lesion.

The experiment described here tests the effect of intracerebroventricular (icv) injection of nitric oxide (NO) precursors, such as L-arginine (L-arg) and nitroprusside (NP), on the thermogenic changes induced by lesion of the lateral hypothalamus (LH). The firing rate of the nerves innervating interscapular brown adipose tissue (IBAT), along with IBAT and colonic temperatures (TIBAT and TC) were monitored in urethane-anaesthetized male Sprague-Dawley rats lesioned in the LH. These variables were measured before and after an icv injection of 4 mumol L-arg or 400 nmol NP. The same variables were also monitored in: a) lesioned rats with icv administration of saline; b) sham-lesioned animals with icv injection of L-arg or NP; c) sham-lesioned rats with icv injection of saline. The results show that L-arg or NP injection reduces the increases in firing rate. TIBAT and TC induced by LH lesion. These findings suggest that NO plays a key role in the thermogenic changes following LH lesion.

Non-shivering thermogenesis during prostaglandin E1 fever in rats: role of the cerebral cortex.

We have tested the hypothesis that there is a role for the cerebral cortex in the control of non-shivering thermogenesis during fever induced by prostaglandin E1 (PGE1). While under urethan anesthesia, the firing rate of nerves innervating interscapular brown adipose tissue (IBAT), IBAT and colonic temperatures (TIBAT and Tc) and oxygen (O2) consumption were monitored during the fever from PGE1 injection (400 and 800 ng) in a lateral cerebral ventricle in controls and in functionally decorticated Sprague-Dawley rats. Rats were functionally decorticated by applying 3.3 M KCl solution on the frontal cortex which causes cortical spreading depression (CSD). Pyrogen injections caused dose-related increases in firing rate, TIBAT, Tc and O2 consumption and CSD reduced these enhancements. Our findings indicate that the cerebral cortex could be involved in the control of non-shivering thermogenesis during PGE1-induced febrile response.

Thermogenetic changes following frontal neocortex stimulation.

Heat production changes were recorded in anesthetized female Sprague-Dawley rats after stimulation of orbital frontal neocortex. The results obtained show that orbital frontal neocortex stimulation significantly increases oxygen consumption, and core and brown adipose tissue temperature. The increase was more substantial after stimulation of left than right cortex. Administration of the beta-blocker propranolol abolished the increase in O2 consumption, core and brown adipose tissue temperature following cortical stimulation. These results are in agreement with our previous research showing that functional ablation of cerebral cortex blocked the increase in thermogenesis following lateral hypothalamic lesion. These findings also show that the orbital frontal neocortex in rats is specifically involved in the control of thermogenesis.

Nitric oxide reduces body temperature and sympathetic input to brown adipose tissue during PGE1-hyperthermia.

The firing rate of the nerves innervating interscapular brown adipose tissue (IBAT) and IBAT and colonic temperatures (TIBAT and TC were monitored in urethane-anaesthetized male Sprague-Dawley rats. These variables were measured for 40 min before (baseline values) and 40 min after a 4 micromoles L-arginine (L-arg) or 400 nmoles nitroprusside (NP) injection in a lateral cerebral ventricle and an intracerebroventricular administration of 500 ng prostaglandin E1 (PGE1). The same variables were monitored in other rats with L-arg or NP or PGE1 administration alone. No drug was injected in control rats. The results show that L-arg or NP injection reduces the increases in firing rate, TIBAT, Tc induced by PGE1. These findings suggest that nitric oxide is important in the control of thermogenic changes during the PGE1 hyperthermia.