Full-endoscopic discectomy for thoracic disc herniations: a single-arm meta-analysis of safety and efficacy outcomes.

INTRODUCTION: Surgical intervention is the treatment of choice in patients with thoracic disc herniation with refractory symptoms and progressive myelopathy. Due to high occurrence of complications from open surgery, minimally invasive approaches are desirable. Nowadays, endoscopic techniques have become increasingly popular and full-endoscopic surgery can be performed in the thoracic spine with low complication rates. METHODS: Cochrane Central, PubMed, and Embase databases were systematically searched for studies that evaluated patients who underwent full-endoscopic spine thoracic surgery. The outcomes of interest were dural tear, myelopathy, epidural hematoma, recurrent disc herniation, and dysesthesia. In the absence of comparative studies, a single-arm meta-analysis was performed. RESULTS: We included 13 studies with a total of 285 patients. Follow-up ranged from 6 to 89 months, age from 17 to 82 years, with 56.5% male. The procedure was performed under local anesthesia with sedation in 222 patients (77.9%). A transforaminal approach was used in 88.1% of the cases. There were no cases of infection or death reported. The data showed a pooled incidence of outcomes as follows, with their respective 95% confidence intervals (CI)-dural tear (1.3%; 95% CI 0-2.6%); dysesthesia (4.7%; 95% CI 2.0-7.3%); recurrent disc herniation (2.9%; 95% CI 0.6-5.2%); myelopathy (2.1%; 95% CI 0.4-3.8%); epidural hematoma (1.1%; 95% CI 0.2-2.5%); and reoperation (1.7%; 95% CI 0.1-3.4%). CONCLUSION: Full-endoscopic discectomy has a low incidence of adverse outcomes in patients with thoracic disc herniations. Controlled studies, ideally randomized, are warranted to establish the comparative efficacy and safety of the endoscopic approach relative to open surgery.

How can Transnational Municipal Networks foster local collaborative governance regimes for environmental management?

While there is abundant literature on Transnational Municipal Networks (TMNs) and collaborative governance regimes (CGRs) to respond to environmental change, few studies address TMNs as exogenous agents driving CGRs dynamics locally. TMNs have emerged as important actors in multilevel governance, providing formal structures for local governments to share best practices, access funding and influence the international policy arena on global environmental change. We argue that TMNs also have a pivotal role in the activation of CGRs and in strengthening the four dimensions of Capacity for Joint Action (CJA) identified by the literature: structural arrangements, leadership, knowledge and learning, and resources. Through the analysis of empirical evidence, based on semi-structured interviews and data sources (2014-2021), we investigate how TMNs built capacities and facilitated the emergence of a CGR in the case of waste management and composting initiative in Gangtok, India. In this case, two TMNs developed a toolkit to enable the local government to assess climate risks in the context of urbanization, poverty and vulnerability in Asia. Furthermore, at a certain point the local actors started to provide knowledge to the TMNs to be shared among other local governments and activating new CGRs, such as the case of Gangtok, which is active in sharing its knowledge in composting and climate change actions with other cities.

Environmental governance for sustainable development in Asia.

Because of the size of its population and economy, good environmental governance in Asia is fundamental not only for the well-being of the region's population but also for the health of the planet. This article introduces the challenges of governing the environment in Asia. The issue evaluates the outcomes and institutional changes in selected countries related to substantive environmental issues such as air pollution, water quality, municipal solid waste, transport, land use, and climate change. By synthesizing the main research issues, methodology and findings of the growing literature on the region, we highlight the trends in environmental governance and gaps in policy and research. Despite the efforts made, there are still remaining environmental governance challenges to be addressed by both the academics and practitioners in Asia.

The 'Heart Kuznets Curve'? Understanding the relations between economic development and cardiac conditions.

As countries turn wealthier, some health indicators, such as child mortality, seem to have well-defined trends. However, others, including cardiovascular conditions, do not follow clear linear patterns of change with economic development. Abnormal blood pressure is a serious health risk factor with consequences for population growth and longevity as well as public and private expenditure in health care and labor productivity. This also increases the risk of the population in certain pandemics, such as COVID-19. To determine the correlation of income and blood pressure, we analyzed time-series for the mean systolic blood pressure (SBP) of men's population (mmHg) and nominal Gross Domestic Product per capita (GDPPC) for 136 countries from 1980 to 2008 using regression and statistical analysis by Pearson's correlation (r). Our study finds a trend similar to an inverted-U shaped curve, or a 'Heart Kuznets Curve'. There is a positive correlation (increase GDPPC, increase SBP) in low-income countries, and a negative correlation in high-income countries (increase GDPPC, decrease SBP). As country income rises people tend to change their diets and habits and have better access to health services and education, which affects blood pressure. However, the latter two may not offset the rise in blood pressure until countries reach a certain income. Investing early in health education and preventive health care could avoid the sharp increase in blood pressure as countries develop, and therefore, avoiding the 'Heart Kuznets Curve' and its economic and human impacts.

The highly efficient powerhouse in the Wistar audiogenic rat, an epileptic rat strain.

The Wistar audiogenic rat (WAR) is an animal model of tonic-clonic epileptic seizures, developed after genetic selection by sister × brother inbreeding of Wistar rats susceptible to sound stimuli. Although metabolic changes have been described in this strain, nothing is known about its mitochondrial metabolism. Here, we addressed mitochondrial aspects of oxidative phosphorylation, oxidative stress, biogenesis, and dynamics in liver, skeletal muscle, and heart of male WARs and correlating them with physiological aspects of body metabolism. The results showed higher mitochondrial content, respiration rates in phosphorylation and noncoupled states, and H2O2 production in WARs. Liver presented higher content of peroxisome proliferator-activated receptor-γ coactivator 1α (PGC1α) and mammalian target of rapamycin, proteins related to mitochondrial biogenesis. In agreement, isolated liver mitochondria from WARs showed higher respiration rates in phosphorylation state and ADP-to-O ratio, as well as higher content of proteins related to electron transport chain ATP synthase, TCA cycle, and mitochondrial fusion and fission compared with their Wistar counterparts. Mitochondria with higher area and perimeter and more variable shapes were found in liver and soleus from WARs in addition to lower reduced-to-oxidized glutathione ratio. In vivo, WARs demonstrated lower body mass and energy expenditure but higher food and water intake and amino acid oxidation. When exposed to a running test, WARs reached higher speed and resisted for a longer time and distance than their Wistar controls. In conclusion, the WAR strain has mitochondrial changes in liver, skeletal muscle, and heart that improve its mitochondrial capacity of ATP production, making it an excellent rat model to study PGC1α overexpression and mitochondrial function in different physiological conditions or facing pathological challenges.

Intergovernmental relations for environmental governance: Cases of solid waste management and climate change in two Malaysian States.

Institutions for environmental governance evolve differently across sectors. They also vary in the same sector when governments at two levels (national and subnational) have different political alignments. As the policy environment becomes more complex, with global problems like climate change, and politics more dividing, better coordination among various levels of government is a tough governance challenge. Scholars and practitioners need to realize how best to build institutions to bridge the various levels of government in different political environments and environmental sectors. This research analyzes the influence of intergovernmental relations in two environmental sectors in two localities with contrasting political alignments between two levels of government. It draws lessons from solid waste management and climate policy in two Malaysian states (Johor and Penang). In an evolving State and new policy arenas, when formal institutions for intergovernmental relations may not be effectively in place, politics play an even larger role through the discretionary power of federal and subnational authorities. An open political process can help with the engagement of different political groups and civil society to bring legitimacy, resources and efficiency to environmental management, if it is done with robust intergovernmental institutions; otherwise, intergovernmental relations can also become a tool for zero-sum games, cronyism and patrimonialism, which can undermine policies, and result in inefficiencies and ineffectiveness in environmental management.

The Wistar Audiogenic Rat (WAR) strain and its contributions to epileptology and related comorbidities: History and perspectives.

In the context of modeling epilepsy and neuropsychiatric comorbidities, we review the Wistar Audiogenic Rat (WAR), first introduced to the neuroscience international community more than 25years ago. The WAR strain is a genetically selected reflex model susceptible to audiogenic seizures (AS), acutely mimicking brainstem-dependent tonic-clonic seizures and chronically (by audiogenic kindling), temporal lobe epilepsy (TLE). Seminal neuroethological, electrophysiological, cellular, and molecular protocols support the WAR strain as a suitable and reliable animal model to study the complexity and emergent functions typical of epileptogenic networks. Furthermore, since epilepsy comorbidities have emerged as a hot topic in epilepsy research, we discuss the use of WARs in fields such as neuropsychiatry, memory and learning, neuroplasticity, neuroendocrinology, and cardio-respiratory autonomic regulation. Last, but not least, we propose that this strain be used in "omics" studies, as well as with the most advanced molecular and computational modeling techniques. Collectively, pioneering and recent findings reinforce the complexity associated with WAR alterations, consequent to the combination of their genetically-dependent background and seizure profile. To add to previous studies, we are currently developing more powerful behavioral, EEG, and molecular methods, combined with computational neuroscience/network modeling tools, to further increase the WAR strain's contributions to contemporary neuroscience in addition to increasing knowledge in a wide array of neuropsychiatric and other comorbidities, given shared neural networks. During the many years that the WAR strain has been studied, a constantly expanding network of multidisciplinary collaborators has generated a growing research and knowledge network. Our current and major wish is to make the WARs available internationally to share our knowledge and to facilitate the planning and execution of multi-institutional projects, eagerly needed to contribute to paradigm shifts in epileptology. This article is part of a Special Issue entitled "Genetic and Reflex Epilepsies, Audiogenic Seizures and Strains: From Experimental Models to the Clinic".

Bicuspid aortic valve outcomes.

BACKGROUND: Bicuspid aortic valve is the most common CHD. Its association with early valvular dysfunction, endocarditis, thoracic aorta dilatation, and aortic dissection is well established. OBJECTIVE: The aim of this study was to assess the incidence and predictors of cardiac events in adults with bicuspid aortic valve. METHODS: We carried out a retrospective analysis of cardiac outcomes in ambulatory adults with bicuspid aortic valve followed-up in a tertiary hospital centre. Outcomes were defined as follows: interventional - intervention on the aortic valve or thoracic aorta; medical - death, aortic dissection, aortic valve endocarditis, congestive heart failure, arrhythmias, or ischaemic heart disease requiring hospital admission; and a composite end point of both. Kaplan-Meier curves were generated to determine event rates, and predictors of cardiac events were determined by multivariate analysis. RESULTS: A total of 227 patients were followed-up over 13±9 years; 29% of patients developed severe aortic valve dysfunction and 12.3% reached ascending thoracic aorta dimensions above 45 mm. At least one cardiac outcome occurred in 38.8% of patients, with an incidence rate at 20 years of follow-up of 47±4%; 33% of patients were submitted to an aortic valve or thoracic aorta intervention. Survival 20 years after diagnosis was 94±2%. Independent predictors of the composite end point were baseline moderate-severe aortic valve dysfunction (hazard ratio, 3.19; 95% confidence interval, 1.35-7.54; p<0.01) and aortic valve leaflets calcification (hazard ratio, 4.72; 95% confidence interval, 1.91-11.64; p<0.005). CONCLUSIONS: In this study of bicuspid aortic valve, the long-term survival was excellent but with occurrence of frequent cardiovascular events. Baseline aortic valve calcification and dysfunction were the only independent predictors of events.

The value of right ventricular longitudinal strain in the evaluation of adult patients with repaired tetralogy of Fallot: a new tool for a contemporary challenge.

OBJECTIVE: The role of right ventricular longitudinal strain for assessing patients with repaired tetralogy of Fallot is not fully understood. In this study, we aimed to evaluate its relation with other structural and functional parameters in these patients. METHODS: Patients followed-up in a grown-up CHD unit, assessed by transthoracic echocardiography, cardiac MRI, and treadmill exercise testing, were retrospectively evaluated. Right ventricular size and function and pulmonary regurgitation severity were assessed by echocardiography and MRI. Right ventricular longitudinal strain was evaluated in the four-chamber view using the standard semiautomatic method. RESULTS: In total, 42 patients were included (61% male, 32±8 years). The mean right ventricular longitudinal strain was -16.2±3.7%, and the right ventricular ejection fraction, measured by MRI, was 42.9±7.2%. Longitudinal strain showed linear correlation with tricuspid annular systolic excursion (r=-0.40) and right ventricular ejection fraction (r=-0.45) (all p<0.05), which in turn showed linear correlation with right ventricular fractional area change (r=0.50), pulmonary regurgitation colour length (r=0.35), right ventricular end-systolic volume (r=-0.60), and left ventricular ejection fraction (r=0.36) (all p<0.05). Longitudinal strain (ß=-0.72, 95% confidence interval -1.41, -0.15) and left ventricular ejection fraction (ß=0.39, 95% confidence interval 0.11, 0.67) were independently associated with right ventricular ejection fraction. The best threshold of longitudinal strain for predicting a right ventricular ejection fraction of <40% was -17.0%. CONCLUSIONS: Right ventricular longitudinal strain is a powerful method for evaluating patients with tetralogy of Fallot. It correlated with echocardiographic right ventricular function parameters and was independently associated with right ventricular ejection fraction derived by MRI.

Elucidating the neurotoxicity of the star fruit.

Caramboxin: Patients suffering from chronic kidney disease are frequently intoxicated after ingesting star fruit. The main symptoms of this intoxication are named in the picture. Bioguided chemical procedures resulted in the discovery of caramboxin, which is a phenylalanine-like molecule that is responsible for intoxication. Functional experiments in vivo and in vitro point towards the glutamatergic ionotropic molecular actions of caramboxin, which explains its convulsant and neurodegenerative properties.

Synthesis, characterization and cytotoxicity of copper (II) complex containing a 2H-benzo[e][1,3]oxazin derivative.

A new cis-dihalo copper(II) complex, [CuII(HLbz)(Cl)2].CH3CN (1), where HLbz = (S)-2-(((2-(2-(pyridin-2-yl)-2H-benzo[e][1,3]oxazin-3(4H)-yl)ethyl)amino)methyl)phenol), was isolated by reacting copper(II) chloride dihydrate and the H2L ligand (H2L = 2,2'-((2-(pyridin-2-yl)imidazolidine-1,3-diyl)bis(methylene))diphenol) in a MeOH/CH3CN (1:3 v/v) mixture. The complex formation occurred via the ligand modification during complexation, producing a unique structure containing 2H-benzo[e][1,3]oxazin, as observed from the single crystal X-ray structure determination. The complex was characterized by elemental analysis, potentiometric titration, spectroscopic techniques (UV-Vis, FT-IR) and conductance measurements. Complex 1 inhibits the growth of myelogenous leukemia cells with an IC50 of 17.3 µmol L-1.

Cyto-, myelo- and chemoarchitecture of the prefrontal cortex of the Cebus monkey.

BACKGROUND: According to several lines of evidence, the great expansion observed in the primate prefrontal cortex (PfC) was accompanied by the emergence of new cortical areas during phylogenetic development. As a consequence, the structural heterogeneity noted in this region of the primate frontal lobe has been associated with diverse behavioral and cognitive functions described in human and non-human primates. A substantial part of this evidence was obtained using Old World monkeys as experimental model; while the PfC of New World monkeys has been poorly studied. In this study, the architecture of the PfC in five capuchin monkeys (Cebus apella) was analyzed based on four different architectonic tools, Nissl and myelin staining, histochemistry using the lectin Wisteria floribunda agglutinin and immunohistochemistry using SMI-32 antibody. RESULTS: Twenty-two architectonic areas in the Cebus PfC were distinguished: areas 8v, 8d, 9d, 12l, 45, 46v, 46d, 46vr and 46dr in the lateral PfC; areas 11l, 11m, 12o, 13l, 13m, 13i, 14r and 14c in the orbitofrontal cortex, with areas 14r and 14c occupying the ventromedial corner; areas 32r, 32c, 25 and 9m in the medial PfC, and area 10 in the frontal pole. This number is significantly higher than the four cytoarchitectonic areas previously recognized in the same species. However, the number and distribution of these areas in Cebus were to a large extent similar to those described in Old World monkeys PfC in more recent studies. CONCLUSIONS: The present parcellation of the Cebus PfC considerably modifies the scheme initially proposed for this species but is in line with previous studies on Old World monkeys. Thus, it was observed that the remarkable anatomical similarity between the brains of genera Macaca and Cebus may extend to architectonic aspects. Since monkeys of both genera evolved independently over a long period of time facing different environmental pressures, the similarities in the architectonic maps of PfC in both genera are issues of interest. However, additional data about the connectivity and function of the Cebus PfC are necessary to evaluate the possibility of potential homologies or parallelisms.

Exposing the Unfinished Business of Building Public Administration in Late Democracies: Lessons from the COVID-19 Response in Brazil.

The COVID-19 pandemic has exposed fundamental flaws in the design of public administration in late democracies. While much writing to date focuses on the initial and vital responses to COVID-19, the magnitude of this event also furthers insights into the risks of incomplete institutional designs and practices, such as the case of Brazil, an example of the administrative flaws in late democracies. This article is not a critique of responses to COVID-19 per se, but an examination of these considering democratization processes that include state-building and the need for another push in administrative and political reforms. Shortcomings in state-building, which existed before COVID-19, inflict heavy costs on society and, if left unaddressed, add to the costs of future disasters and unraveling of support for state and democratic institutions.

New AlIIIZnII and AlIIICuII dinuclear complexes: Phosphatase-like activity and cytotoxicity.

Herein, we report the synthesis and characterization of the first two AlIII(µ-OH)MII (M = Zn (1) and Cu (2)) complexes with the unsymmetrical ligand H2L{2-[[(2-hydroxybenzyl)(2-pyridylmethyl)]aminomethyl]-6-bis(pyridylmethyl)aminomethyl}-4-methylphenol. The complexes were characterized through elemental analysis, X-ray crystallography, IR spectroscopy, mass spectrometry and potentiometric titration. In addition, complex 2 was characterized by electronic spectroscopy. Kinetics studies on the hydrolysis of the model substrate bis(2,4-dinitrophenyl)phosphate by 1 and 2 show Michaelis-Menten behavior, with 1 being slightly more active (8.31%) than 2 (at pH 7.0). The antimicrobial effect of the compounds was studied using four bacterial strains (Staphylococcus aureus, Pseudomonas aeuruginosa, Shigella sonnei and Shigella dysenteriae) and for both complexes the inhibition of bacterial growth was superior to that caused by sulfapyridine, but inferior to that of tetracycline. The dark cytotoxicity and photocytotoxicity (under UV-A light) of the complexes in a chronic myelogenous leukemia cell line were investigated. Complexes 1 and 2 exhibited significant cytotoxic activity against K562 cells, which undergoes a 2-fold increase on applying 5 min of irradiation with UV-A light. Complex 2 was more effective and a good correlation between cytotoxicity and intracellular concentration was observed, the intracellular copper concentration required to inhibit 50% of cell growth being 3.5 × 10-15 mol cell-1.

Inhibition of the renin-angiotensin system prevents seizures in a rat model of epilepsy.

The RAS (renin-angiotensin system) is classically involved in BP (blood pressure) regulation and water-electrolyte balance, and in the central nervous system it has been mostly associated with homoeostatic processes, such as thirst, hormone secretion and thermoregulation. Epilepsies are chronic neurological disorders characterized by recurrent epileptic seizures that affect 1-3% of the world's population, and the most commonly used anticonvulsants are described to be effective in approx. 70% of the population with this neurological alteration. Using a rat model of epilepsy, we found that components of the RAS, namely ACE (angiotensin-converting enzyme) and the AT1 receptor (angiotensin II type 1 receptor) are up-regulated in the brain (2.6- and 8.2-fold respectively) following repetitive seizures. Subsequently, epileptic animals were treated with clinically used doses of enalapril, an ACE inhibitor, and losartan, an AT1 receptor blocker, leading to a significant decrease in seizure severities. These results suggest that centrally acting drugs that target the RAS deserve further investigation as possible anticonvulsant agents and may represent an additional strategy in the management of epileptic patients.

Epilepsy Seizures in Spontaneously Hypertensive Rats After Acoustic Stimulation: Role of Renin-Angiotensin System.

Hypertension is a common comorbidity observed in individuals with epilepsy. Growing evidence suggests that lower blood pressure is associated with reduced frequency and severity of seizures. In this study, we sought to investigate whether the renin-angiotensin system (RAS), which is a critical regulator of blood pressure, is involved in the pathogenesis of audiogenic epilepsy-related seizures in a hypertensive rat model. Spontaneously hypertensive rats (SHRs) were given RAS inhibitors, angiotensin-converting enzyme (ACE) inhibitor or angiotensin II type I receptor (AT1R) antagonist, for 7 days prior to inducing epileptic seizures by acoustic stimulation. After the pretreatment phase, blood pressure (BP) of SHRs normalized as expected, and there was no difference in systolic and diastolic BP between the pretreated SHRs and normotensive rat group (Wistar). Next, treated and untreated SHRs (a high BP control) were individually subjected to acoustic stimuli twice a day for 2 weeks. The severity of tonic-clonic seizures and the severity of temporal lobe epilepsy seizures (product of forebrain recruitment) were evaluated by the mesencephalic severity index (Rossetti et al. scale) and the limbic index (Racine's scale), respectively. Seizures were observed in both untreated (a high BP control) SHRs and in SHRs treated with AT1R antagonist and ACE inhibitor. There was no statistical difference in the mesencephalic severity and limbic index between these groups. Our results demonstrate that SHRs present seizure susceptibility with acoustic stimulation. Moreover, although RAS inhibitors effectively reduce blood pressure in SHR, they do not prevent developing epileptic seizures upon acoustic stimulation in SHR. In conclusion, our study shows that RAS is an unlikely link between hypertension and susceptibility to epileptic seizures induced by acoustic stimulation in SHRs, which is in contrast with the anticonvulsant effect of losartan in other animal models of epilepsy.

Acupuncture can be beneficial for exercise-induced muscle soreness: A randomised controlled trial.

INTRODUCTION: Strenuous physical exercise may cause acute muscle soreness (AMS), which occurs directly after exercise, as well as delayed onset muscle soreness (DOMS), which occurs about 24 h after exercise. Studies of acupuncture's effect on DOMS have had contradictory results, whereas its effect on AMS has not been extensively studied. The main goal of this study was to evaluate acupuncture's effects on AMS and DOMS and on the prevention of DOMS. METHOD: 45 volunteers were randomised into a verum acupuncture group, a sham acupuncture group and a control group. After exercise-induced muscle damage was elicited, muscle soreness and pressure pain threshold were assessed at different time points. The outcome assessments were performed before (T1) and 20 min after the first acupuncture treatment (T2); then, 24 h later, they were performed before (T3) and 20 min after the second acupuncture treatment (T4). In the verum and sham acupuncture groups, acupuncture was performed for 2 min, immediately after T1 and T3 assessments, whereas subjects in the control group simply rested for 2 min without treatment. Verum acupuncture was given at ST34, ST36 and LR3, whereas sham acupuncture was given at three nontraditional points. RESULTS: We found that verum acupuncture can reduce the occurrence of AMS by one-half and DOMS by one-third. We also found specific and nonspecific acupuncture effects in AMS and DOMS. CONCLUSION: The uneven induction of muscle damage identified by our study, as shown by heterogeneity in pressure pain threshold values, may have led to the contradictory results in published studies on DOMS.

Behavioral and EEGraphic Characterization of the Anticonvulsant Effects of the Predator Odor (TMT) in the Amygdala Rapid Kindling, a Model of Temporal Lobe Epilepsy.

Background: Clinical and experimental evidence indicates that olfactory stimulation modulates limbic seizures, either blocking or inducing ictal activity. Objective: We aim to evaluate the behavioral and electroencephalographic (EEGraphic) effects of dihydro-2,4,5-trimethylthiazoline (TMT) olfactory exposure on limbic seizures induced by amygdala rapid kindling (ARK). Materials and Methods: Wistar male rats (280-300 g) underwent stereotaxic surgery for electrode implantation in piriform cortex (PC), hippocampal formation (HIP), and amygdaloid complex (AMYG). Part of the animals was exposed to a saturated chamber with water or TMT, while others had ARK and olfactory exposure prior to the 21st stimulus. Behavioral responses were measured by traditional seizure severity scales (Racine and Pinel and Rovner) and/or by sequential analysis/neuroethology. The electrographic activity of epileptogenic limbic networks was quantified by the occurrence of the first and second EEG afterdischarges, comparing the 1st and 21st stimulus. The spectral analysis [Fast Fourier Transform (FFT)] of the first afterdischarge was performed at the 21st stimulus. Results: TMT olfactory exposure reduced the seizure severity in kindled rats, altering the displayed behavioral sequence. Moreover, TMT decreased the occurrence of first and second afterdischarges, at the 21st stimulus, and altered the spectral features. Conclusions: Both behavioral and EEGraphic evaluations indicated that TMT, a potent molecule with strong biological relevance, in fact, "predator odor," suppressed the epileptiform activity in limbic networks.

Role of the superior colliculus in the expression of acute and kindled audiogenic seizures in Wistar audiogenic rats.

PURPOSE: The role of the superior colliculus (SC) in seizure expression is controversial and appears to be dependent upon the epilepsy model. This study shows the effect of disconnection between SC deep layers and adjacent tissues in the expression of acute and kindling seizures. METHODS: Subcollicular transections, ablation of SC superficial and deep layers, and ablation of only the cerebral cortex were evaluated in the Wistar audiogenic rat (WAR) strain during acute and kindled audiogenic seizures. The audiogenic seizure kindling protocol started 4 days after surgeries, with two acoustic stimuli per day for 10 days. Acute audiogenic seizures were evaluated by a categorized seizure severity midbrain index (cSI) and kindled seizures by a severity limbic index (LI). RESULTS: All subcollicular transections reaching the deep layers of the SC abolished audiogenic seizures or significantly decreased cSI. In the unlesioned kindled group, a reciprocal relationship between limbic and brainstem pattern of seizures was seen. The increased number of stimuli provoked an audiogenic kindling phenomenon. Ablation of the entire SC (ablation group) or of the cerebral cortex only (ctx-operated group) hampered the acquisition of limbic behaviors. There was no difference in cSI and LI between the ctx-operated and ablation groups, but there was a difference between ctx-operated and the unlesioned kindled group. There was also no difference in cSI between SC deep layer transection and ablation groups. Results of histologic analyses were similar for acute and kindled audiogenic seizure groups. CONCLUSIONS: SC deep layers are involved in the expression of acute and kindled audiogenic seizure, and the cerebral cortex is essential for audiogenic kindling development.

Evidence of reciprocal connections between the dorsal raphe nucleus and the retina in the monkey Cebus apella.

Possible connections between the retina and the raphe nuclei were investigated in the monkey Cebus apella by intraocular injection of cholera toxin B subunit (CTb). CTb-positive fibers were seen in the lateral region of the dorsal raphe nucleus (DR) on the side contralateral to the injection, and a few labeled perikarya were observed in the lateral portion of the DR on the ipsilateral side. Our findings suggest that direct and reciprocal connections between the retina and DR may exist in Cebus apella. These connections might be part of an important pathway through which the light/dark cycle influences the activity and/or functional status of raphe neurons, with potential effects on a broad set of neural and behavioral circuits.