rudyvdbrink/CitationDatabase huggingface dataset:
TASK-2 channels contribute to pH sensitivity of retrotrapezoid nucleus chemoreceptor neurons.
The Journal of neuroscience : the official journal of the Society for Neuroscience, 2013

Phox2b-expressing glutamatergic neurons of the retrotrapezoid nucleus (RTN) display properties expected of central respiratory chemoreceptors; they are directly activated by CO2/H(+) via an unidentified pH-sensitive background K(+) channel and, in turn, facilitate brainstem networks that control breathing. Here, we used a knock-out mouse model to examine whether TASK-2 (K2P5), an alkaline-activated background K(+) channel, contributes to RTN neuronal pH sensitivity. We made patch-clamp recordings in brainstem slices from RTN neurons that were identified by expression of GFP (directed by the Phox2b promoter) or β-galactosidase (from the gene trap used for TASK-2 knock-out). Whereas nearly all RTN cells from control mice were pH sensitive (95%, n = 58 of 61), only 56% of GFP-expressing RTN neurons from TASK-2(-/-) mice (n = 49 of 88) could be classified as pH sensitive (>30% reduction in firing rate from pH 7.0 to pH 7.8); the remaining cells were pH insensitive (44%). Moreover, none of the recorded RTN neurons from TASK-2(-/-) mice selected based on β-galactosidase activity (a subpopulation of GFP-expressing neurons) were pH sensitive. The alkaline-activated background K(+) currents were reduced in amplitude in RTN neurons from TASK-2(-/-) mice that retained some pH sensitivity but were absent from pH-insensitive cells. Finally, using a working heart-brainstem preparation, we found diminished inhibition of phrenic burst amplitude by alkalization in TASK-2(-/-) mice, with apneic threshold shifted to higher pH levels. In conclusion, alkaline-activated TASK-2 channels contribute to pH sensitivity in RTN neurons, with effects on respiration in situ that are particularly prominent near apneic threshold.
Long-term consequences of the absence of leptin signaling in early life.
eLife, 2019

Leptin regulates energy balance and also exhibits neurotrophic effects during critical developmental periods. However, the actual role of leptin during development is not yet fully understood. To uncover the importance of leptin in early life, the present study restored leptin signaling either at the fourth or tenth week of age in mice formerly null for the leptin receptor (LepR) gene. We found that some defects previously considered irreversible due to neonatal deficiency of leptin signaling, including the poor development of arcuate nucleus neural projections, were recovered by LepR reactivation in adulthood. However, LepR deficiency in early life led to irreversible obesity via suppression of energy expenditure. LepR reactivation in adulthood also led to persistent reduction in hypothalamic
Toxicology of Blister Agents: Is Melatonin a Potential Therapeutic Option?
Diseases (Basel, Switzerland), 2021

Blister or vesicant chemical warfare agents (CWAs) have been widely used in different military conflicts, including World War I and the Iran-Iraq War. However, their mechanism of action is not fully understood. Sulfur and nitrogen mustard exert toxic effects not only through the alkylation of thiol-bearing macromolecules, such as DNA and proteins, but also produce free radicals that can develop direct toxic effects in target organs such as the eyes, skin, and respiratory system. The lack of effective treatments against vesicant CWAs-induced injury makes us consider, in this complex scenario, the use and development of melatonin-based therapeutic strategies. This multifunctional indoleamine could facilitate neutralization of the oxidative stress, modulate the inflammatory response, and prevent the DNA damage, as well as the long-term health consequences mediated by vesicant CWAs-induced epigenetic mechanisms. In this context, it would be essential to develop new galenic formulations for the use of orally and/or topically applied melatonin for the prophylaxis against vesicant CWAs, as well as the development of post-exposure treatments in the near future.
Amplitude-Integrated Electroencephalography Improves the Identification of Infants with Encephalopathy for Therapeutic Hypothermia and Predicts Neurodevelopmental Outcomes at 2 Years of Age.
The Journal of pediatrics, 2017

To examine whether using an amplitude-integrated electroencephalography (aEEG) severity pattern as an entry criterion for therapeutic hypothermia better selects infants with hypoxic-ischemic encephalopathy and to assess the time-to-normal trace for aEEG and magnetic resonance imaging (MRI) lesion load as 24-month outcome predictors.
Risk factors of white matter hyperintensities in South Asian patients with transient ischemic attack and minor stroke.
Neuroradiology, 2020

Aging and increased burden of cardiovascular risk factors are associated with severity of white matter hyperintensity (WMH). We assessed the burden and risk factor profile of WMHs in South Asian patients with transient ischemic attack (TIA) and minor stroke.
SGIP1α functions as a selective endocytic adaptor for the internalization of synaptotagmin 1 at synapses.
Molecular brain, 2019

Proper sorting of exocytosed synaptic vesicle (SV) proteins into individual SVs during endocytosis is of the utmost importance for the fidelity of subsequent neurotransmission. Recent studies suggest that each SV protein is sorted into individual SVs by its own dedicated adaptors as well as by association between SV proteins. The SH3-containing GRB2-like protein 3-interacting protein 1 (SGIP1), an ortholog of Fer/Cip4 homology domain-only (FCHo) proteins, contains a μ-homology domain (μHD) and binds AP-2 and Eps15, thus functioning as an endocytic regulator of clathrin-mediated endocytosis (CME). Its longest isoform SGIP1α is predominantly expressed in the brain but the functional significance of SGIP1 in SV recycling remains unknown. Here, we found that SGIP1α, a brain-specific long isoform of SGIP1 binds synaptotagmin1 (Syt1) via its μHD and promotes the internalization of Syt1 on the neuronal surface. The small hairpin RNA (shRNA)-mediated knockdown (KD) of SGIP1α caused selective impairment of Syt1 internalization at hippocampal synapses and it was fully rescued by coexpression of the shRNA-resistant form of SGIP1α in KD neurons. We further found that the μHD of SGIP1α is structurally similar to those of AP-2 and stonin2, and mutations at Trp771 and Lys781, which correspond to Syt1-recognition motifs of AP-2 and stonin2, to Ala bound less efficiently to Syt1 and failed to rescue the endocytic defect of Syt1 caused by KD. Our results indicate that SGIP1α is an endocytic adaptor dedicated to the retrieval of surface-stranded Syt1. Since endocytic sorting of Syt1 is also mediated by the overlapping activities of synaptic vesicle glycoprotein 2A/B (SV2A/B) and stonin2, our results suggest that complementary fail-safe mechanism by these proteins ensures high fidelity of Syt1 retrieval.
Efficacy of bilateral repetitive transcranial magnetic stimulation for negative symptoms of schizophrenia: results of a multicenter double-blind randomized controlled trial.
Psychological medicine, 2015

Few studies have investigated the efficacy of repetitive transcranial magnetic stimulation (rTMS) treatment for negative symptoms of schizophrenia, reporting inconsistent results. We aimed to investigate whether 10 Hz stimulation of the bilateral dorsolateral prefrontal cortex during 3 weeks enhances treatment effects.
Nucleophilic Substitution of Hydrogen Facilitated by Quinone Methide Moieties in Benzo[cd]azulen-3-ones.
Organic letters, 2017

The built-in o- and p-QM (QM = quinone methide) moieties in benzo[cd]azulen-3-ones account for an easy switch between the bridged 10π- and 6π-aromatic systems in organic synthesis. We report conjugate additions, oxidative nucleophilic substitutions of hydrogen, and reversible Michael additions under very mild conditions. In the presence of thiol nucleophiles, the protonated σ
POMC Neurons Dysfunction in Diet-induced Metabolic Disease: Hallmark or Mechanism of Disease?
Neuroscience, 2020

One important lesson from the last decade of studies in the field of systemic energy metabolism is that obesity is first and foremost a brain disease. Hypothalamic neurons dysfunction observed in response to chronic metabolic stress is a key pathogenic node linking consumption of hypercaloric diets with body weight gain and associated metabolic sequelae. A key hypothalamic neuronal population expressing the neuropeptide Pro-opio-melanocortin (POMC) displays altered electrical activity and dysregulated neuropeptides production capacity after long-term feeding with hypercaloric diets. However, whether such neuronal dysfunction represents a consequence or a mechanism of disease, remains a subject of debate. Here, we will review and highlight emerging pathogenic mechanisms that explain why POMC neurons undergo dysfunctional activity in response to caloric overload, and critically address whether these mechanisms may be causally implicated in the physiopathology of obesity and of its associated co-morbidities.
Consequences of temperature-induced sex reversal on hormones and brain in Nile tilapia (Oreochromis niloticus).
Hormones and behavior, 2020

Fish present a wide variety of sex determination systems ranging from strict genetic control (genetic sex determination, GSD) to strict environmental control (environmental sex determination, ESD). Temperature is the most frequent environmental factor influencing sex determination. Nile tilapia (Oreochromis niloticus) is characterized by GSD with male heterogamety (XY/XX), which can be overridden by exposure to high masculinizing temperatures. Sex reversed Nile tilapia (XX males; neomales) have been described in the wild and seem undistinguishable from XY males, but little is known about their physiology. The consideration of climate change urges the need to understand the possible physiological and behavioral consequences of such a sex reversal. The present study compared XX females, XY males and XX neomales for testis maturation, circulating sex -steroid concentrations as well as the size and number of neurons expressing arginine-vasotocin [AVT] and gonadotropin releasing hormone [GnRH] which are involved in sociosexual pathways. The results revealed that temperature-induced sex reversal does not affect testis maturation nor circulating sex steroid concentrations. Neomales show dramatically fewer GnRH1-immunoreactive (-ir) neurons than males and females, despite the observed normal testis physiology. Neomales also present fewer AVT-ir neurons in the magnocellular preoptic area than females and bigger AVT-ir neurons in the parvocellular POA (pPOA) compared to both males and females. The absence of consequences of sex reversal on testis development and secretions despite the reduced numbers of GnRH1 neurons suggests the existence of compensatory mechanisms in the hypothalamic-pituitary-gonadal axis, while the larger pPOA AVT neurons might predict a more submissive behavior in neomales.
Functional Meningeal Lymphatics and Cerebrospinal Fluid Outflow.
Journal of neuroimmune pharmacology : the official journal of the Society on NeuroImmune Pharmacology, 2018

Functional meningeal lymphatic system plays a crucial role in outflow of cerebrospinal fluid. Metabolites and neurotoxins in the cerebrospinal fluid may be excreted via this system and accumulate in the cervical lymph nodes. In this letter, we highlighted the role of functional meningeal lymphatics and cerebrospinal fluid outflow.
Second Generation Electronic Nicotine Delivery System Vape Pen Exposure Generalizes as a Smoking Cue.
Nicotine & tobacco research : official journal of the Society for Research on Nicotine and Tobacco, 2018

Second generation electronic nicotine delivery systems (ENDS; also known as e-cigarettes, vaporizers or vape pens) are designed for a customized nicotine delivery experience and have less resemblance to regular cigarettes than first generation "cigalikes." The present study examined whether they generalize as a conditioned cue and evoke smoking urges or behavior in persons exposed to their use.
Dietary zinc reduction, pyruvate supplementation, or zinc transporter 5 knockout attenuates β-cell death in nonobese diabetic mice, islets, and insulinoma cells.
The Journal of nutrition, 2012

Pancreatic zinc (Zn(2+)) concentrations are linked to diabetes and pancreatic dysfunction, but Zn(2+) is also required for insulin processing and packaging. Zn(2+) released with insulin increases β-cell pancreatic death after streptozotocin toxin exposure in vitro and in vivo. Triosephosphate accumulation, caused by NAD(+) loss and glycolytic enzyme dysfunction, occur in type-1 diabetics (T1DM) and animal models. We previously showed these mechanisms are also involved in Zn(2+) neurotoxicity and are attenuated by nicotinamide- or pyruvate-induced restoration of NAD(+) concentrations, Zn(2+) restriction, or inhibition of Sir2 proteins. We tested the hypothesis that similar Zn(2+)- and NAD(+)-mediated mechanisms are involved in β-cell toxicity in models of ongoing T1DM using mouse insulinoma cells, islets, and nonobese diabetic (NOD) mice. Zn(2+), streptozotocin, and cytokines caused NAD(+) loss and death in insulinoma cells and islets, which were attenuated by Zn(2+) restriction, pyruvate, nicotinamide, NAD(+), and inhibitors of Sir2 proteins. We measured diabetes incidence and mortality in NOD mice and demonstrated that pyruvate supplementation, or genetic or dietary Zn(2+) reduction, attenuated these measures. T-lymphocyte infiltration, punctate Zn(2+) staining, and β-cell loss increased with time in islets of NOD mice. Dietary Zn(2+) restriction or Zn(2+) transporter 5 knockout reduced pancreatic Zn(2+) staining and increased β-cell mass, glucose homeostasis, and survival in NOD mice, whereas Zn(2+) supplementation had the opposite effects. Pancreatic Zn(2+) reduction or NAD(+) restoration (pyruvate or nicotinamide supplementation) are suggested as novel targets for attenuating T1DM.
The processing of chimeric and dichotic emotional stimuli by connected and disconnected cerebral hemispheres.
Behavioural brain research, 2014

Hemispheric asymmetries have been widely explored in both the visual and the auditory domain, but little is known about hemispheric asymmetries in audio-visual integration. We compared the performance of a partially callosotomized patient, a total split-brain patient and a control group during the evaluation of the emotional valence of chimeric faces and dichotic syllables (an emotional syllable in one ear and white noise in the other ear) presented unimodally (only faces or only syllables) or bimodally (faces and syllables presented simultaneously). Stimuli could convey happy and sad expressions and participants were asked to evaluate the emotional content of each presentation, using a 5-point Likert scale (from very sad to very happy). In unimodal presentations, the partially callosotomized patient's judgments depended on the emotional valence of the stimuli processed by the right hemisphere, whereas those of the total split-brain patient showed the opposite lateralization; in these conditions, the control group did not show asymmetries. Moreover, in bimodal presentations, results provided support for the valence hypothesis (i.e., left asymmetry for positive emotions and vice versa) in both the control group and the partially callosotomized patient, whereas the total split-brain patient showed a tendency to evaluate the emotional content of the right hemiface even when asked to focus on the acoustic modality. We conclude that partial and total hemispheric disconnections reveal opposite patterns of hemispheric asymmetry in auditory, visual and audio-visual emotion processing. These results are discussed in the light of the right-hemisphere hypothesis and the valence hypothesis.
Expression of leucine-rich repeat kinase 2 (LRRK2) inhibits the processing of uMtCK to induce cell death in a cell culture model system.
Bioscience reports, 2011

PD (Parkinson's disease) is the most common neurodegenerative movement disorder. Mutations in LRRK2 (leucine-rich repeat kinase 2) gene are linked to the most common inherited and sporadic PD. Overexpression of LRRK2 and its mutants could induce mitochondrial-dependent neuronal apoptosis. However, the underlying mechanism remains elusive. We have identified several novel LRRK2 interacting proteins and showed that LRRK2 can interact with three components of the PTPC (permeability transition pore complex) including ANT (adenine nucleotide translocator), VDAC (voltage-dependent anion channel) and uMtCK [ubiquitous MtCK (mitochondrial creatine kinase)]. Those components have been reported to be involved in the permeability of mitochondrial membrane. We provide evidence that LRRK2 is likely to interact with uMtCK directly and expression of LRRK2 and its mutant form can suppress the processing of the immature form of uMtCK. LRRK2 expression keeps the uMtCK preprotein on the outer mitochondrial membrane instead of entering the mitochondria. In addition, the expression of both wild-type and mutant forms of LRRK2 promotes the interaction between ANT and VDAC, which plays a role in permeabilization transition pore opening. Finally, LRRK2-induced cell death can be suppressed by uMtCK. Our findings imply that LRRK2 can interact directly with uMtCK to block its entry into mitochondria and its subsequent processing, resulting in inhibition of mitochondrial energy channelling. Meanwhile, the decrease of uMtCK in mitochondria results in elevated interaction between ANT and VDAC and leads to neuronal apoptosis. Thus, our study provides the rational for clinical trials using creatine to treat PD and supports the notion of exploiting LRRK2 as a drug target for PD.
Gamma-glutamyltransferase in alcohol use disorders: Modification of decision limits in relation to treatment goals?
Scandinavian journal of clinical and laboratory investigation, 2010

Serum gamma-glutamyltransferase (GGT) is recommended as a marker for alcohol use disorders by the Swedish National Guidelines for Addiction, although it has a low sensitivity and specificity. GGT is inexpensive and easily accessible but additional knowledge is required on how to use the marker in patients with various levels of alcohol intake. Levels of GGT were obtained from 37 male social drinkers (< 100 grams pure alcohol weekly) and 18 former alcohol-dependent males with long-term (6 +/- 5 years) abstinence. Reproducibility was calculated through repeated blood samplings. Mean serum activity of GGT, in former alcohol-dependent males, was 0.26 microkat/L with an intra-class correlation coefficient of 0.85. In social drinkers, these figures were 0.34 microkat/L and 0.92, respectively. In treatment of males, with the goal of abstinence, upper reference limit is suggested to be 0.40 microkat/L. Goals of non-harmful drinking (< 100 grams weekly) suggest higher limits (0.62 microkat/L). Thirty percent increase of GGT should be suggestive of relapse.
Intermittent hypoxia conditioning protects mitochondrial cytochrome c oxidase of rat cerebellum from ethanol withdrawal stress.
Journal of applied physiology (Bethesda, Md. : 1985), 2012

Intermittent hypoxia (IH) conditioning minimizes neurocognitive impairment and stabilizes brain mitochondrial integrity during ethanol withdrawal (EW) in rats, but the mitoprotective mechanism is unclear. We investigated whether IH conditioning protects a key mitochondrial enzyme, cytochrome c oxidase (COX), from EW stress by inhibiting mitochondrially directed apoptotic pathways involving cytochrome c, Bax, or phosphor-P38 (pP38). Male rats completed two cycles of a 4-wk ethanol diet (6.5%) and 3 wk of EW. An IH program consisting of 5-10 bouts of 5-8 min of mild hypoxia (9.5-10% inspired O(2)) and 4 min of reoxygenation for 20 consecutive days began 3 days before the first EW period. For some animals, vitamin E replaced IH conditioning to test the contributions of antioxidant mechanisms to IH's mitoprotection. During the second EW, cerebellar-related motor function was evaluated by measuring latency of fall from a rotating rod (Rotarod test). After the second EW, COX activity in cerebellar mitochondria was measured by spectrophotometry, and COX, cytochrome c, Bax, and pP38 content were analyzed by immunoblot. Mitochondrial protein oxidation was detected by measuring carbonyl contents and by immunochemistry. Earlier IH conditioning prevented motor impairment, COX inactivation, depletion of COX subunit 4, protein carbonylation, and P38 phosphorylation during EW. IH did not prevent cytochrome c depletion during EW, and Bax content was unaffected by EW ± IH. Vitamin E treatment recapitulated IH protection of COX, and P38 inhibition attenuated protein oxidation during EW. Thus IH protects COX and improves cerebellar function during EW by limiting P38-dependent oxidative damage.
Molecular and electrophysiological changes in the prefrontal cortex-amygdala-dorsal periaqueductal grey pathway during persistent pain state and fear-conditioned analgesia.
Physiology & behavior, 2011

Fear-conditioned analgesia (FCA) is the reduction in pain responding which is expressed upon re-exposure to a context previously paired with an aversive stimulus. Projections along the prefrontal cortex (PFC)-amygdala-dorsal periaqueductal grey (dPAG) pathway may mediate FCA. However, there is a paucity of studies measuring both molecular and electrophysiological changes in this pathway in rats expressing persistent pain-related behaviour or FCA. Male Lister-hooded rats, with stimulating and recording electrodes implanted in the amygdala and dPAG, respectively, either received or did not receive footshock (0.4 mA) paired with context, followed 23.5 h later by an intraplantar injection of saline or formalin (50 μL, 2.5%) into the right hindpaw. Thirty minutes post-formalin/saline, rats were re-exposed to the context for 15 min, during which pain-related behaviours were assessed in addition to evoked field potential recordings in the amygdala-dPAG pathway. Immediately after the 15-minute trial, PFC tissue was isolated for measurement of total and phosphorylated extracellular-signal regulated kinase (ERK) by western blotting. Formalin-evoked nociceptive behaviour in non-fear-conditioned rats was associated with increased field potential amplitude in the dPAG and increased relative expression of phospho-ERK in the PFC. These effects were abolished in rats expressing FCA. Fear conditioning in non-formalin treated rats was associated with increased phospho-ERK in the PFC but no change in field potential amplitude in the dPAG. Together, these data suggest differential, state-dependent alterations in electrophysiological activity and ERK phosphorylation along the PFC-amygdala-dPAG pathway during pain, conditioned fear, and FCA.
The epidemiology of convulsive status epilepticus in children: a critical review.
Epilepsia, 2007

There is ongoing debate regarding the most appropriate definition of status epilepticus. This depends upon the research question being asked. Based on the most widely used "30 min definition," the incidence of childhood convulsive status epilepticus (CSE) in developed countries is approximately 20/100,000/year, but will vary depending, among others, on socioeconomic and ethnic characteristics of the population. Age is a main determinant of the epidemiology of CSE and, even within the pediatric population there are substantial differences between older and younger children in terms of incidence, etiology, and frequency of prior neurological abnormalities or prior seizures. Overall, incidence is highest during the first year of life, febrile CSE is the single most common cause, around 40% of children will have previous neurological abnormalities and less than 15% will have a prior history of epilepsy. Outcome is mainly a function of etiology. However, the causative role of CSE itself on mesial temporal sclerosis and subsequent epilepsy or the influence of age, duration, or treatment on outcome of CSE remains largely unknown. Future studies should aim at clarifying these issues and identifying specific ethnic, genetic, or socioeconomic factors associated with CSE to pinpoint potential targets for its primary and secondary prevention.