Preclinical Positron Emission Tomography (PET) of Prosthetic Joint Infection Using a Nitro-Prodrug of 2-[F]F--Aminobenzoic Acid ([F]F-PABA).

Deep-seated bacterial infections are difficult to detect and diagnose due to the lack of specific clinical imaging modalities. Therefore, the bacteria-specific positron emission tomography radiotracer 2-[F]fluoro-4-nitrobenzoic acid ([F]FNB) was developed, which is reduced to 2-[F]fluoro-4-aminobenzoic acid ([F]F-PABA) by bacterial nitroreductases and has improved pharmacokinetics compared to the parent compound. PET imaging demonstrated that the uptake of 2-[F]fluoro-4-nitrobenzoic acid in a clinically relevant prosthetic joint infection model was up to ∼4-fold higher in the infected joint compared to the contralateral joint.

Seizures Cause Prolonged Impairment of Ventilation, CO Chemoreception and Thermoregulation.

Sudden unexpected death in epilepsy (SUDEP) has been linked to respiratory dysfunction, but the mechanisms underlying this association remain unclear. Here we found that both focal and generalized convulsive seizures (GCSs) in epilepsy patients caused a prolonged decrease in the hypercapnic ventilatory response (HCVR; a measure of respiratory CO chemoreception). We then studied (Dravet syndrome; DS) and (D/+) mice of both sexes, two models of SUDEP, and found that convulsive seizures caused a postictal decrease in ventilation and severely depressed the HCVR in a subset of animals.

Sudden unexpected death in epilepsy: Respiratory mechanisms.

Epilepsy is one of the most common chronic neurologic diseases, with a prevalence of 1% in the US population. Many people with epilepsy live normal lives, but are at risk of sudden unexpected death in epilepsy (SUDEP). This mysterious comorbidity of epilepsy causes premature death in 17%-50% of those with epilepsy.

A ketogenic diet protects DBA/1 and Scn1a mice against seizure-induced respiratory arrest independent of ketosis.

Patients with uncontrolled epilepsy have a high risk of sudden unexpected death in epilepsy (SUDEP). Seizure-induced respiratory arrest (S-IRA) is thought to be the determining cause of death in many cases of SUDEP. The goal of the present study was to use Scn1a (Dravet Syndrome, DS) and DBA/1 mice to determine: (1) the effect of a ketogenic diet (KD) on S-IRA and (2) the relationship between serum ketones and the protective effect of a KD.

How glycobiology can help us treat and beat the COVID-19 pandemic.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged during the last months of 2019, spreading throughout the world as a highly transmissible infectious illness designated as COVID-19. Vaccines have now appeared, but the challenges in producing sufficient material and distributing them around the world means that effective treatments to limit infection and improve recovery are still urgently needed. This review focuses on the relevance of different glycobiological molecules that could potentially serve as or inspire therapeutic tools during SARS-CoV-2 infection.

Amygdala lesions reduce seizure-induced respiratory arrest in DBA/1 mice.

Sudden unexpected death in epilepsy (SUDEP) is the most common cause of death in patients with refractory epilepsy. Human studies and animal models suggest that respiratory arrest is the initiating event leading to death in many cases of SUDEP. It has previously been reported that the onset of apnea can coincide with the spread of seizures to the amygdala, and apnea can be reproduced by electrical stimulation of the amygdala.

Time of Day and a Ketogenic Diet Influence Susceptibility to SUDEP in Mice.

Sudden unexpected death in epilepsy (SUDEP) is a major cause of mortality in patients with drug-resistant epilepsy. Most SUDEP cases occur in bed at night and are preceded by a generalized tonic-clonic seizure (GTCS). Dravet syndrome (DS) is a severe childhood-onset epilepsy commonly caused by mutations in the gene.

Mapping the neuroanatomy of functional decline in Alzheimer's disease from basic to advanced activities of daily living.

Background: Impairments in activities of daily living (ADL) are a criterion for Alzheimer's disease (AD) dementia. However, ADL gradually decline in AD, impacting on advanced (a-ADL, complex interpersonal or social functioning), instrumental (IADL, maintaining life in community), and finally basic functions (BADL, activities related to physiological and self-maintenance needs). Information and communication technologies (ICT) have become an increasingly important aspect of daily functioning.

Severe peri-ictal respiratory dysfunction is common in Dravet syndrome.

Dravet syndrome (DS) is a severe childhood-onset epilepsy commonly due to mutations of the sodium channel gene SCN1A. Patients with DS have a high risk of sudden unexplained death in epilepsy (SUDEP), widely believed to be due to cardiac mechanisms. Here we show that patients with DS commonly have peri-ictal respiratory dysfunction.

Neuroanatomical Comparison of the "Word" and "Picture" Versions of the Free and Cued Selective Reminding Test in Alzheimer's Disease.

Episodic memory tests with cued recall, such as the Free and Cued Selective Reminding Test (FCSRT), allow for the delineation of hippocampal and prefrontal atrophy contributions to memory performance in Alzheimer's disease (AD). Both Word and Picture versions of the test exist but show different profiles, with the Picture version usually scoring higher across different cohorts. One possible explanation for this divergent performance between the different modality versions of the test might be that they rely on different sets of neural correlates.

Tau Platelets Correlate with Regional Brain Atrophy in Patients with Alzheimer's Disease.

Background: Intracellular neurofibrillary tangles are part of the core pathology of Alzheimer's disease (AD), which are mainly composed of hyperphosphorylated tau protein.

Objectives: The purpose of this study is to determine whether high molecular weight (HMW) or low molecular weight (LMW) tau protein levels, as well as the ratio HMW/LMW, present in platelets correlates with brain magnetic resonance imaging (MRI) structural changes in normal and cognitively impaired subjects.

Methods: We examined 53 AD patients and 37 cognitively normal subjects recruited from two Memory Clinics at the Universidad de Chile.

Medullary 5-HT neurons: Switch from tonic respiratory drive to chemoreception during postnatal development.

Serotonin (5-HT) neurons contribute to respiratory chemoreception in adult mice, but it is unclear whether they play a similar role in neonatal mice. We studied breathing during development in Lmx1b mice, which lack 5-HT neurons. From postnatal days 1-7 (P1-P7), ventilation of Lmx1b mice breathing room air was 50% of WT mice (p<0.

Frequency of Cholelithiasis and Biliary Pathology in the Easter Island Rapanui and Non-Rapanui Populations.

Background: Chile is one of the countries with the highest prevalence of cholelithiasis worldwide, considering the Mapuche ethnicity as a risk factor for developing this pathology. Moreover, cholelithiasis is the main risk factor for developing gallbladder cancer, being the fifth cause of cancer death in Chile. The purpose of this study was to compare the frequency of cholelithiasis and biliary pathology among the population belonging to Rapanui ethnicity and non-Rapanui population living on Easter Island.

The Alteration of Neonatal Raphe Neurons by Prenatal-Perinatal Nicotine. Meaning for Sudden Infant Death Syndrome.

Nicotine may link maternal cigarette smoking with respiratory dysfunctions in sudden infant death syndrome (SIDS). Prenatal-perinatal nicotine exposure blunts ventilatory responses to hypercapnia and reduces central respiratory chemoreception in mouse neonates at Postnatal Days 0 (P0) to P3. This suggests that raphe neurons, which are altered in SIDS and contribute to central respiratory chemoreception, may be affected by nicotine.

Description of deaths on Easter Island, 2000-2012 period.

Easter Island is a small island of 180 km2, located 3,800 km from the Chilean coast and one of the most isolated inhabited places in the world. Since the mid-twentieth century, it has been undergoing an epidemiological transition in relation to the causes of death, from a predominance of infectious to non-communicable diseases (NCDs) such as cardiovascular ailments and cancer. The aim of this study is to describe the causes of death to Easter Island between 2000 and 2012, so the statistical records of Hanga Roa Hospital and death certificates were reviewed.

Unusual origin of the left ophthalmic artery from the basilar trunk.

The formation of the ophthalmic artery (OA) is a complex process with two different proposed embryological steps for its development. Several anatomical variants have been described. We present a very unusual origin of the ophthalmic artery from the basilar trunk, in a 45-year-old male with a history of pontine hemorrhagic stroke.

Middle cerebral artery occlusion with moyamoya-like vessels and aneurysms. A report of two cases.

We describe two cases of aneurysmal rupture in moyamoya-like vessels in middle cerebral artery occlusion. This phenomenon was previously described in severe steno-occlusive disease and accounts for the hemorrhagic presentation. To our knowledge, these are the second and third clinical cases published in modern neuroradiological literature.

Fluid structural analysis of human cerebral aneurysm using their own wall mechanical properties.

Computational Structural Dynamics (CSD) simulations, Computational Fluid Dynamics (CFD) simulation, and Fluid Structure Interaction (FSI) simulations were carried out in an anatomically realistic model of a saccular cerebral aneurysm with the objective of quantifying the effects of type of simulation on principal fluid and solid mechanics results. Eight CSD simulations, one CFD simulation, and four FSI simulations were made. The results allowed the study of the influence of the type of material elements in the solid, the aneurism's wall thickness, and the type of simulation on the modeling of a human cerebral aneurysm.

Endovascular treatment of aneurysm arising from fenestration of the supraclinoid internal carotid artery--two case reports.

We report two cases of aneurysm located in a fenestration of the supraclinoid internal carotid artery, an extremely rare anatomical variant, and describe the feasibility of endovascular treatment using two different strategies applicable for each case. Each presented aneurysm had a particular location on the fenestration, which led to different endovascular approaches. In one case, the aneurysm arose from the proximal junction of fenestration, involving both of its limbs.

Functional expression of the α7 and α4-containing nicotinic acetylcholine receptors on the neonatal rat carotid body.

The carotid bodies (CBs) are chemosensory organs that respond to hypoxemia with transmitter neurosecretion, leading to a respiratory reflex response. It has been proposed that acetylcholine is a key regulator of transmitter release through activation of presynaptic nicotinic acetylcholine receptors (nAChRs). In the present work, we studied the identity of such nAChRs and their contribution to catecholamine release from CBs.

Numerical investigation of the hemodynamics in anatomically realistic lateral cerebral aneurysms.

Hemodynamically induced stress plays an important role in the progression and rupture of cerebral aneurysms. The current work describes computational fluid dynamics (CFD) simulations in anatomically realistic models of cerebral aneurysms. Twenty lateral aneurysms models were investigated.

Alterations in cholinergic sensitivity of respiratory neurons induced by pre-natal nicotine: a mechanism for respiratory dysfunction in neonatal mice.

Nicotine may link cigarette smoking during pregnancy with sudden infant death syndrome (SIDS). Pre-natal nicotine leads to diminished ventilatory responses to hypercarbia and reduced central chemoreception in mice at post-natal days 0-3. We studied how pre-natal nicotine exposure changes the cholinergic contribution to central respiratory chemoreception in neonatal isolated brainstem-spinal cord and slice preparations.

Respiratory dysfunctions induced by prenatal nicotine exposure.

1. Maternal tobacco smoking is the principal risk factor associated with sudden infant death syndrome (SIDS), a leading cause of death of infants under 1 year of age. Victims of SIDS show a higher incidence of respiratory control abnormalities, including central apnoeas, delayed arousal responses and diminished ventilatory chemoreflexes.

Prenatal to early postnatal nicotine exposure impairs central chemoreception and modifies breathing pattern in mouse neonates: a probable link to sudden infant death syndrome.

Nicotine is a neuroteratogen and is the likely link between maternal cigarette smoking during pregnancy and sudden infant death syndrome (SIDS). Osmotic minipumps were implanted in 5-7 d CF1 pregnant mice to deliver nicotine bitartrate (60 mg Kg(-1) day(-1)) or saline (control) solutions for up to 28 d. Prenatal to early postnatal nicotine exposure did not modify the number of newborns per litter or their postnatal growth; however, nicotine-exposed neonates hypoventilated and had reduced responses to hypercarbia (inhalation of air enriched with 10% CO(2) for 20 min) and hypoxia (inhalation of 100% N(2) for 20 s) at postnatal days 0-3 (P0-P3).

Blood flow dynamics in patient-specific cerebral aneurysm models: the relationship between wall shear stress and aneurysm area index.

Hemodynamics plays an important role in the progression and rupture of cerebral aneurysms. The temporal and spatial variations in wall shear stress (WSS) within the aneurysmal sac are hypothesized to be correlated with the growth and rupture of the aneurysm. The current work describes the blood flow dynamics in 34 patient-specific models of saccular aneurysms located in the region of the anterior and posterior circulation of the circle of Willis.