Increased vesicular monoamine transporter enhances dopamine release and opposes Parkinson disease-related neurodegeneration in vivo.

Disruption of neurotransmitter vesicle dynamics (transport, capacity, release) has been implicated in a variety of neurodegenerative and neuropsychiatric conditions. Here, we report a novel mouse model of enhanced vesicular function via bacterial artificial chromosome (BAC)-mediated overexpression of the vesicular monoamine transporter 2 (VMAT2; Slc18a2). A twofold increase in vesicular transport enhances the vesicular capacity for dopamine (56%), dopamine vesicle volume (33%), and basal tissue dopamine levels (21%) in the mouse striatum. The elevated vesicular capacity leads to an increase in stimulated dopamine release (84%) and extracellular dopamine levels (44%). VMAT2-overexpressing mice show improved outcomes on anxiety and depressive-like behaviors and increased basal locomotor activity (41%). Finally, these mice exhibit significant protection from neurotoxic insult by the dopaminergic toxicant 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), as measured by reduced dopamine terminal damage and substantia nigra pars compacta cell loss. The increased release of dopamine and neuroprotection from MPTP toxicity in the VMAT2-overexpressing mice suggest that interventions aimed at enhancing vesicular capacity may be of therapeutic benefit in Parkinson disease.

Adenosine A2A receptor antagonism reverses inflammation-induced impairment of microglial process extension in a model of Parkinson's disease.

Microglia, the immune cells of the central nervous system, constantly survey the parenchyma in the healthy brain to maintain homeostasis. When a disturbance, such as cell death, results in ATP release in vivo, microglial processes respond by utilizing P2Y12 purinergic receptors to trigger extension toward the site of damage. Processes ultimately surround the injury site, preventing the spread of harmful cellular constituents and assisting with tissue repair. In contrast to the healthy brain, many neurodegenerative diseases, including Parkinson's disease, are characterized by the presence of neuroinflammation. Yet, the ability of microglia to respond to tissue damage under pro-inflammatory conditions has not been well studied. To assess the ability of microglia to respond to tissue injury and localized cell death in the context of Parkinson's disease, we performed confocal imaging of acute brain slices from mice with microglia-specific green fluorescent protein expression. Microglia in coronal slices containing the substantia nigra extend processes toward a mechanical injury in a P2Y12 receptor-dependent manner. However, microglia in mice treated for 5days with 20mg/kg/day 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) show significantly reduced process displacement toward the injury compared to microglia in control animals. Pre-treatment of slices from MPTP-injected mice with the A2A receptor-selective antagonist preladenant restores the ability of activated microglia to respond to tissue damage. These data support the hypothesis that chronic inflammation impedes microglial motility in response to further injury, such as cell death, and suggest that some aspects of the neuroprotection observed with adenosine A2A receptor antagonists may involve direct or indirect actions at microglia.

Transthoracic Echocardiography Is Possible in Morbidly Obese Patients During Bariatric Surgery.

BACKGROUND: To evaluate the feasibility of an abbreviated focus-assessed transthoracic echocardiography protocol in morbidly obese patients. The purpose of this study was to evaluate whether good images could be obtained from this particularly difficult group of patients for whom acoustic imaging is often poor. Heart imaging could be helpful for cardiopulmonary screening and real-time monitoring. METHODS: The study included 186 morbidly obese patients, who underwent laparoscopic bariatric surgery. The mean patient age was 32 years (range 21-52), and there were 95 males. The parasternal long and short axes and apical 4 and 5 chambers were evaluated. RESULTS: In 95% of the patients, at least one view was obtained. In 78%, two views were obtained, and in 31% of the patients, all views and measurements could be performed. CONCLUSION: In obese patients, a modified focused echocardiography examination performed by anesthesiologists in the intraoperative period of morbid obese patients is feasible. The image quality was sufficient to undergo interpretation.

RING finger protein 11 (RNF11) modulates susceptibility to 6-OHDA-induced nigral degeneration and behavioral deficits through NF-κB signaling in dopaminergic cells.

Chronic activation of the NF-κB pathway is associated with progressive neurodegeneration in Parkinson's disease (PD). Given the role of neuronal RING finger protein 11 (RNF11) as a negative regulator of the NF-κB pathway, in this report we investigated the function of RNF11 in dopaminergic cells in PD-associated neurodegeneration. We found that RNF11 knockdown in an in vitro model of PD mediated protection against 6-OHDA-induced toxicity. In converse, over-expression of RNF11 enhanced 6-OHDA-induced dopaminergic cell death. Furthermore, by directly manipulating NF-κB signaling, we showed that the observed RNF11-enhanced 6-OHDA toxicity is mediated through inhibition of NF-κB-dependent transcription of TNF-α, antioxidants GSS and SOD1, and anti-apoptotic factor BCL2. Experiments in an in vivo 6-OHDA rat model of PD recapitulated the in vitro results. In vivo targeted RNF11 over-expression in nigral neurons enhanced 6-OHDA toxicity, as evident by increased amphetamine-induced rotations and loss of nigral dopaminergic neurons as compared to controls. This enhanced toxicity was coupled with the downregulation of NF-κB transcribed GSS, SOD1, BCL2, and neurotrophic factor BDNF mRNA levels, in addition to decreased TNF-α mRNA levels in ventral mesenchephalon samples. In converse, knockdown of RNF11 was associated with protective phenotypes and increased expression of above-mentioned NF-κB transcribed genes. Collectively, our in vitro and in vivo data suggest that RNF11-mediated inhibition of NF-κB in dopaminergic cells exaggerates 6-OHDA toxicity by inhibiting neuroprotective responses while loss of RNF11 inhibition on NF-κB activity promotes neuronal survival. The decreased expression of RNF11 in surviving cortical and nigral tissue detected in PD patients, thus implies a compensatory response in the diseased brain to PD-associated insults. In summary, our findings demonstrate that RNF11 in neurons can modulate susceptibility to 6-OHDA toxicity through NF-κB mediated responses. This neuron-specific role of RNF11 in the brain has important implications for targeted therapeutics aimed at preventing neurodegeneration.

Exposure to the polybrominated diphenyl ether mixture DE-71 damages the nigrostriatal dopamine system: role of dopamine handling in neurotoxicity.

In the last several decades polybrominated diphenyl ethers (PBDEs) have replaced the previously banned polychlorinated biphenyls (PCBs) in multiple flame retardant utilities. As epidemiological and laboratory studies have suggested PCBs as a risk factor for Parkinson's disease (PD), the similarities between PBDEs and PCBs suggest that PBDEs have the potential to be neurotoxic to the dopamine system. The purpose of this study was to evaluate the neurotoxic effects of the PBDE mixture, DE-71, on the nigrostriatal dopamine system and address the role of altered dopamine handling in mediating this neurotoxicity. Using an in vitro model system we found DE-71 effectively caused cell death in a dopaminergic cell line as well as reducing the number of TH+ neurons isolated from VMAT2 WT and LO animals. Assessment of DE-71 neurotoxicity in vivo demonstrated significant deposition of PBDE congeners in the brains of mice, leading to reductions in striatal dopamine and dopamine handling, as well as reductions in the striatal dopamine transporter (DAT) and VMAT2. Additionally, DE-71 elicited a significant locomotor deficit in the VMAT2 WT and LO mice. However, no change was seen in TH expression in dopamine terminal or in the number of dopamine neurons in the substantia nigra pars compacta (SNpc). To date, these are the first data to demonstrate that exposure to PBDEs disrupts the nigrostriatal dopamine system. Given their similarities to PCBs, additional laboratory and epidemiological research should be considered to assess PBDEs as a potential risk factor for PD and other neurological disorders.

Industrial toxicants and Parkinson's disease.

The exposure of the human population to environmental contaminants is recognized as a significant contributing factor for the development of Parkinson's disease (PD) and other forms of parkinsonism. While pesticides have repeatedly been identified as risk factors for PD, these compounds represent only a subset of environmental toxicants that we are exposed to on a regular basis. Thus, non-pesticide contaminants, such as metals, solvents, and other organohalogen compounds have also been implicated in the clinical and pathological manifestations of these movement disorders and it is these non-pesticide compounds that are the subject of this review. As toxic exposures to these classes of compounds can result in a spectrum of PD or PD-related disorders, it is imperative to appreciate shared clinico-pathological characteristics or mechanisms of action of these compounds in order to further delineate the resultant disorders as well as identify improved preventive strategies or therapeutic interventions.

Traumatic brain injury in adult rats causes progressive nigrostriatal dopaminergic cell loss and enhanced vulnerability to the pesticide paraquat.

Parkinson's disease (PD) is a neurodegenerative disorder characterized by the loss of nigrostriatal dopaminergic neurons and the accumulation of alpha-synuclein. Both traumatic brain injury (TBI) and pesticides are risk factors for PD, but whether TBI causes nigrostriatal dopaminergic cell loss in experimental models and whether it acts synergistically with pesticides is unknown. We have examined the acute and long-term effects of TBI and exposure to low doses of the pesticide paraquat, separately and in combination, on nigrostriatal dopaminergic neurons in adult male rats. In an acute study, rats received moderate TBI by lateral fluid percussion (LFP) injury, were injected with saline or paraquat (10 mg/kg IP) 3 and 6 days after LFP, were sacrificed 5 days later, and their brains processed for immunohistochemistry. TBI alone increased microglial activation in the substantia nigra, and caused a 15% loss of dopaminergic neurons ipsilaterally. Paraquat increased the TBI effect, causing a 30% bilateral loss of dopaminergic neurons, reduced striatal tyrosine hydroxylase (TH) immunoreactivity more than TBI alone, and induced alpha-synuclein accumulation in the substantia nigra pars compacta. In a long-term study, rats received moderate LFP, were injected with saline or paraquat at 21 and 22 weeks post-injury, and were sacrificed 4 weeks later. At 26 weeks post injury, TBI alone induced a 30% bilateral loss of dopaminergic neurons that was not exacerbated by paraquat. These data suggest that TBI is sufficient to induce a progressive degeneration of nigrostriatal dopaminergic neurons. Furthermore, TBI and pesticide exposure, when occurring within a defined time frame, could combine to increase the PD risk.

Susceptibilidad antimicrobiana de dos periodontopatógenos a moxifloxacina y amoxicilina ácido clavulánico / Antimicrobial susceptibility of moxifloxacin and amoxicillin clavulanic acid against two periodontopathogens

Fundamento: se ha documentado un aumento importante de la resistencia de algunos perio-dontopatógenos a los antimicrobianos usados de forma tradicional como coadyuvantes en la terapia periodontal. Objetivo: evaluar la susceptibilidad de Aggregatibacter actinomycetemcomitans y Porphyromonas gingivalis a la moxifloxacina y amoxicilina ácido clavulánico en pacientes con periodontitis crónica. Métodos: se realizó un estudio observacional de corte transversal el universo estuvo constitui-do por 30 pacientes con periodontitis crónica. La toma y procesamiento de las muestras microbiológicas se realizaron mediante protocolos descritos de forma previa. Para evaluar la susceptibilidad de A. actinomycetemcomitans y P. gingivalis frente a la moxifloxacina y amoxicilina ácido clavulánico, se usaron pruebas de difusión en disco. Resultados: P. gingivalis fue el microorganismo más prevalente en la población estudiada. Los dos periodontopatógenos cultivados fueron muy sensibles a los dos antimicrobianos evaluados. Conclusiones: A. actinomycetemcomitans y P. gingivalis son muy susceptibles a la moxifloxacina y la amoxicilina ácido clavulánico en la población estudiada, donde se convierte de esta manera en una alternativa coadyuvante para el tratamiento de la periodontitis.

Background: a significant increase in the resistance of some antimicrobial periodontopathogens traditionally used as adjuncts in periodontal therapy has been reported. Objective: to assess the susceptibility of Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis to moxifloxacin and amoxicillin clavulanic acid in patients with chronic periodontitis. Methods: an observational cross-sectional study of the universe composed of 30 patients with chronic periodontitis was conducted. Microbiological samples processing were performed following protocols described previously. Disk diffusion tests were used to assess the susceptibility of A. actinomycetemcomitans and P. gingivalis against moxifloxacin and amoxicillin clavulanic acid. Results: P. gingivalis was the most prevalent microorganism in the population studied. The two periodontopathogens grown were highly sensitive to both antimicrobials tested. Conclusions: A. actinomycetemcomitans and P. gingivalis are highly susceptible to moxifloxacin and amoxicillin clavulanic acid in this population, therefore it is an alternative adjuvant for the treatment of periodontitis.

Efecto inhibidor del crecimiento bacteriano in vitro del plasma rico en plaquetas / Inhibitory effect of bacterial growth in vitro platelet-rich plasma

Objetivo: determinar el efecto inhibidor del crecimiento bacteriano del Plasma Rico en Plaquetas (PRP) sobre el Estafilococo aureus. Material y método: se tomó 20cc de sangre a cada uno de los cinco pacientes que intervinieron en el estudio, obteniéndose el PRP activado con trombina y bovina en cada una de las muestras. Se realizaron dos procedimientos diferentes, procesándose cada muestra por quintuplicado. En el primero se enfrenta el PRP puro y combinado con Ampicilina 500mg con el Estafilococo aureus, midiendo el halo de inhibición que se forma a las 24 horas. En el segundo procedimiento se enfrentó a los mismos compuestos con la misma bacteria, pero exponiéndolos en diferentes tiempos -uno, tres, cinco y quince minutos-, para observar la acción del PRP sobre le crecimiento bacteriano en diferentes momentos. Para el análisis de las variables se emplearon las pruebas ANOVA, prueba de esfericidad de Mauchly, la prueba de Scheffé y la corrección de Bonferrini. Resultados: el PRP no presentó ningún efecto sobre el crecimiento bacteriano en ninguna de las pruebas realizadas. Los halos de inhibición que se obtuvieron por parte del PRP en la primera prueba tuvieron un valor de 0 en todas las muestras, y el número de recuento de las colonias obtenidas en la segunda prueba fue similar al testigo negativo. Conclusiones: el Plasma Rico en Plaquetas no presenta un efecto inhibidor sobre el crecimiento bacteriano in vitro del Estafilococo aureus.

Objective: to determine the inhibitory effect of bacterial growth in vitro platelet-rich plasma (PRP) on Staphylococcus aureus. Material and method: 20cc of blood were taken from each one of the five patients that participated in this study, and PRP activated with each bovine thrombin was obtained from each one of these samples. Two different methods were used; the procedure was repeated witch each sample five times. In the first method, pure PRP combined with Ampicillin 500mg is exposed to Staphylococcus aureus, measuring the inhibition halo that is formed 24 hours later. In the second method we expose the same elements to the same bacteria but for different times, for one, three, five and fifteen minutes, to observe the PRP action in the different moments of bacterial growth. Variables were analyzed using ANOVA, W de Mauchly, test of Sheffé and test of Bonferrini. Results: PRP did not show any action on the study bacteria in any of the samples. The inhibition halo obtained by PRP in the first test was zero in all of the samples, and the number of colony count obtained by PRP in the second test was abundant, similar to negatives witness. Conclusions: the platelet-rich-plasma does not have an inhibitory effect on bacterial growth in vitro of Staphylococcus aureus.

Infecciones por cándida en una unidad de terapia intensiva: revisión de casos clínicos y análisis de la bibliografía / Candida infections in an Intensive Care Unit: review of clinics cases

Se presentan 3 casos de infecciones sistémicas micóticas, por Candida, en un recién nacido pretérmino de 1000 gramos con sífilis connatal, en un lactante con invaginación intestinal y peritonitis y resección intestinal y en un lactante con SHU que requirió diálisis peritoneal. Se analizaron los factores predisponentes para la instalación de candidiasis: uso de antibióticos, uso de catéteres endovenosos y nutrición parenteral. Hasta el momento, el tratamiento se basa en la administración de Anfotericina B y en retirar precozmente las protesis (catéter intravasculares, vesicales, sonda endotraqueal). Es importante pesquisar las complicaciones oftalmológicas (endoftalmitis) y ecográficamente, las renales y cardíacas