[Executive functions in patients with obstructive sleep apnea: exploring the prefrontal model]. / Funciones ejecutivas en pacientes con apnea obstructiva del sueño: explorando el modelo prefrontal.

INTRODUCTION: According to the prefrontal model, individuals with obstructive sleep apnea (OSA) manifest behaviours mimicking dysexecutive syndrome as a result of blood gas abnormalities and sleep fragmentation. OBJECTIVE: To compare executive functions in OSA patients with normative values and explore their relationship with blood gas abnormalities and sleep fragmentation. PATIENTS AND METHODS: Patients were recruited from the wider community and from a tertiary care hospital. The score obtained in the neuropsychological assessment was compared with Student's t-test for a sample. A multiple linear regression analysis was subsequently estimated, using polysomnographic parameters of hypercapnia, hypoxemia and sleep fragmentation as the predictor variables, and the executive function score as the variable to be predicted. RESULTS: Although the neuropsychological assessment performance of 26% of this sample was classified as executive impairment, indicators of sleep fragmentation and gas abnormalities failed to predict the performance of executive functions. CONCLUSION: A proportion of the patients with OSA presented performance similar to a dysexecutive syndrome; however, the factors underlying and fostering this type of cognitive manifestation remain unclear. Early treatment for this public health problem could be the best tool available for improving quality of life and preventing health risks.

TITLE: Funciones ejecutivas en pacientes con apnea obstructiva del sueño: explorando el modelo prefrontal.Introducción. El modelo prefrontal propone que los individuos con apnea obstructiva del sueño (AOS) manifiestan conductas similares a un síndrome disejecutivo como resultado de las alteraciones de gases en la sangre y la fragmentación del sueño. Objetivo. Comparar las funciones ejecutivas en pacientes con AOS con valores normativos y explorar su relación con las alteraciones de gases en la sangre y la fragmentación del sueño. Pacientes y métodos. Se reclutó a pacientes de la comunidad general y de un hospital de tercer nivel. La puntuación obtenida en la evaluación neuropsicológica se contrastó con la t de Student para una muestra. Posteriormente, se estimó un análisis de regresión lineal múltiple mediante parámetros polisomnográficos de hipercapnia, hipoxemia y fragmentación del sueño como variables predictoras, y la puntuación de funciones ejecutivas como variable que se debe predecir. Resultados. Pese a que el desempeño en la evaluación neuropsicológica del 26% de esta muestra se clasificó como alteración ejecutiva, los indicadores de fragmentación del sueño y alteraciones de gases no predijeron el desempeño ejecutivo. Conclusión. Una fracción de los pacientes con AOS mostró un desempeño similar a un síndrome disejecutivo; no obstante, permanecen indefinidos los factores que subyacen y favorecen este tipo de manifestaciones cognitivas. La atención temprana de este problema de salud pública podría ser la mejor herramienta disponible en aras de mejorar la calidad de vida y prevenir riesgos a la salud.

Lactobacillus strains reduce the toxic effects of a subchronic exposure to arsenite through drinking water.

The aim of the present study was to determine the efficacy of LAB strains in reducing the intestinal toxicity of arsenite [As(III)] and its tissue accumulation. For this purpose, Balb/c mice were randomly separated in four groups. One group received no treatment (control), one group received only As(III) (30 mg/L) via drinking water and the remaining two groups received As(III) via water and a daily dose of two LAB strains (Lactobacillus intestinalis LE1 and Lacticaseibacillus paracasei BL23) by gavage during 2 months. The results show that both strains reduce the pro-inflammatory and pro-oxidant response observed at the colonic level, partially restore the expression of the intercellular junction proteins (CLDN3 and OCLN) responsible for the maintenance of epithelial integrity, and increase the synthesis of the major mucin of the colonic mucus layer (MUC2), compared to animals treated with As(III) alone. Microbial metabolism of short-chain fatty acids also undergoes a recovery and the levels of fatty acids in the lumen reach values similar to those of untreated animals. All these positive effects imply the restoration of mucosal permeability, and a reduction of the marker of endotoxemia LPS binding protein (LBP). Treatment with the bacteria also has a direct impact on intestinal absorption, reducing the accumulation of As in the internal organs. The data suggest that the protective effect may be due to a reduced internalization of As(III) in intestinal tissues and to a possible antioxidant and anti-inflammatory activity of the bacteria through activation of pathways such as Nrf2 and IL-10. In vitro tests show that the protection may be the result of the combined action of structural and metabolic components of the LAB strains.

Preclinical evaluation of a tool for insertion force measurements in cochlear implant surgery.

PURPOSE: Trauma that may be inflicted to the inner ear (cochlea) during the insertion of an electrode array (EA) in cochlear implant (CI) surgery can significantly decrease the hearing outcome of patients with residual hearing. Interaction forces between the EA and the cochlea are a promising indicator for the likelihood of intracochlear trauma. However, insertion forces have only been measured in laboratory setups. We recently developed a tool to measure the insertion force during CI surgery. Here, we present the first ex vivo evaluation of our tool with a focus on usability in the standard surgical workflow. METHODS: Two CI surgeons inserted commercially available EAs into three temporal bone specimens. The insertion force and the orientation of the tool were recorded together with camera footage. The surgeons answered a questionnaire after each insertion to evaluate the surgical workflow with respect to CI surgery. RESULTS: The EA insertion using our tool was rated successful in all 18 trials. The surgical workflow was evaluated to be equivalent to standard CI surgery. Minor handling challenges can be overcome through surgeon training. The peak insertion forces were 62.4 mN ± 26.7 mN on average. Peak forces significantly correlated to the final electrode insertion depth, supporting the assumption that the measured forces mainly correspond to intracochlear events and not extracochlear friction. Gravity-induced forces of up to 28.8 mN were removed from the signal, illustrating the importance of the compensation of such forces in manual surgery. CONCLUSION: The results show that the tool is ready for intraoperative use. In vivo insertion force data will improve the interpretability of experimental results in laboratory settings. The implementation of live insertion force feedback to surgeons could further improve residual hearing preservation.

Drilling accuracy evaluation of a mouldable surgical targeting system for minimally invasive access to anatomic targets in the temporal bone.

PURPOSE: Minimally invasive cochlear implant surgery using a micro-stereotactic surgical targeting system with on-site moulding of the template aims for a reliable, less experience-dependent access to the inner ear under maximal reduction of trauma to anatomic structures. We present an accuracy evaluation of our system in ex-vivo testing. METHODS: Eleven drilling experiments were performed on four cadaveric temporal bone specimens. The process involved preoperative imaging after affixing the reference frame to the skull, planning of a safe trajectory preserving relevant anatomical structures, customization of the surgical template, execution of the guided drilling and postoperative imaging for determination of the drilling accuracy. Deviation between the drilled and desired trajectories was measured at different depths. RESULTS: All drilling experiments were successfully performed. Other than purposely sacrificing the chorda tympani in one experiment, no other relevant anatomy, such as facial nerve, chorda tympani, ossicles or external auditory canal were harmed. Deviation between the desired and achieved path was found to be 0.25 ± 0.16 mm at skulls' surface and 0.51 ± 0.35 mm at the target level. The closest distance of the drilled trajectories' outer circumference to the facial nerve was 0.44 mm. CONCLUSIONS: We demonstrated the usability for drilling to the middle ear on human cadaveric specimen in a pre-clinical setting. Accuracy proved to be suitable for many applications such as procedures within the field of image-guided neurosurgery. Promising approaches to reach sufficient submillimetre accuracy for CI surgery have been outlined.

Intestinal homeostasis disruption in mice chronically exposed to arsenite-contaminated drinking water.

Chronic exposure to inorganic arsenic [As(III) and As(V)] affects about 200 million people, and is linked to a greater incidence of certain types of cancer. Drinking water is the main route of exposure, so, in endemic areas, the intestinal mucosa is constantly exposed to the metalloid. However, studies on the intestinal toxicity of inorganic As are scarce. The objective of this study was to evaluate the toxicity of a chronic exposure to As(III) on the intestinal mucosa and its associated microbiota. For this purpose, BALB/c mice were exposed during 6 months through drinking water to As(III) (15 and 30 mg/L). Treatment with As(III) increased reactive oxygen species (43-64%) and lipid peroxidation (8-51%). A pro-inflammatory response was also observed, evidenced by an increase in fecal lactoferrin (23-29%) and mucosal neutrophil infiltration. As(III) also induced an increase in the colonic levels of pro-inflammatory cytokines (24-201%) and the activation of some pro-inflammatory signaling pathways. Reductions in the number of goblet cells and mucus production were also observed. Moreover, As(III) exposure resulted in changes in gut microbial alpha diversity but no differences in beta diversity. This suggested that the abundance of some taxa was significantly affected by As(III), although the composition of the population did not show significant alterations. Analysis of differential taxa agreed with this, 21 ASVs were affected in abundance or variability, especially ASVs from the family Muribaculaceae. Intestinal microbiota metabolism was also affected, as reductions in fecal concentration of short-chain fatty acids were observed. The effects observed on different components of the intestinal barrier may be responsible of the increased permeability in As(III) treated mice, evidenced by an increase in fecal albumin (48-66%). Moreover, serum levels of Lipopolysaccharide binding proteins and TNF-α were increased in animals treated with 30 mg/L of As(III), suggesting a low-level systemic inflammation.

A Tool to Enable Intraoperative Insertion Force Measurements for Cochlear Implant Surgery.

OBJECTIVE: Residual hearing preservation during cochlear implant (CI) surgery is closely linked to the magnitude of intracochlear forces acting during the insertion process. So far, these forces have only been measured in vitro. Therefore, the range of insertion forces and the magnitude of damage-inducing thresholds in the human cochlea in vivo remain unknown. We aimed to develop a method to intraoperatively measure insertion forces without negatively affecting the established surgical workflow. Initial experiments showed that this requires the compensation of orientation-dependent gravitational forces. METHODS: We devised design requirements for a force-sensing manual insertion tool. Experienced CI surgeons evaluated the proposed design for surgical safety and handling quality. Measured forces from automated and manual insertions into an artificial cochlea model were evaluated against data from a static external force sensor representing the gold standard. RESULTS: The finalized manual insertion tool uses an embedded force sensor and inertial measurement unit to measure insertion forces. The evaluation of the proposed design shows the feasibility of orientation-independent insertion force measurements. Recorded forces correspond well to externally recorded reference forces after reliable removal of gravitational disturbances. CI surgeons successfully used the tool to insert electrode arrays into human cadaver cochleae. CONCLUSION: The presented positive evaluation poses the first step towards intraoperative use of the proposed tool. Further in vitro experiments with human specimens will ensure reliable in vivo measurements. SIGNIFICANCE: Intraoperative insertion force measurements enabled by this tool will provide insights on the relationship between forces and hearing outcomes in cochlear implant surgery.

Ex Vivo Evaluation of a Minimally Invasive Approach for Cochlear Implant Surgery.

OBJECTIVES: Drilling a minimally invasive access to the inner ear is a demanding task in which a computer-assisted surgical system can support the surgeon. Herein, we describe the design of a new micro-stereotactic targeting system dedicated to cochlear implant (CI) surgery and its experimental evaluation in an ex vivo study. METHODS: The proposed system consists of a reusable, bone-anchored reference frame, and a patient-specific drilling jig on top of it. Individualization of the jig is simplified to a single counterbored hole drilled out of a blank. For accurate counterboring, the setup includes a manufacturing device for individual positioning of the blank. The system was tested in a preclinical setting using twelve human cadaver donors. Cone beam computed tomograph (CBCT) scans were obtained and a drilling trajectory was planned pointing towards the basal part of the cochlea. The surgical drill was moved forward manually and slowly while the jig constrained the drill along the predetermined path. RESULTS: Drilling could be performed with preservation of facial nerve in all specimens. The mean error caused by the system at the target point in front of the cochlea was 0.30 mm ± 0.11 mm including an inaccuracy of 0.09 mm ± 0.03 mm for counterboring the guiding aperture into the jig. CONCLUSION: Feasibility of the proposed system to perform a minimally invasive posterior tympanotomy approach was shown successfully in all specimens. SIGNIFICANCE: First evaluation of the new system in a comprehensive ex vivo study demonstrating sufficient accuracy and the feasibility of the whole concept.

Toward a cochlear implant electrode array with shape memory effect for post-insertion perimodiolar positioning.

For cochlear implants (CI) a final position of the electrode array (EA) along the inner wall of the spirally shaped cochlea is considered to be beneficial because it results in a closer proximity to the auditory nerve fibers. A shape memory effect (SME) could facilitate such shift of the EA toward the cochlear inner wall, but its implementation remains to be solved. The current study presents an EA prototype featuring the SME with minute adjustments of the material properties of Nitinol, a shape memory alloy, in combination with a suitable cooling strategy to prevent premature curling. Ten samples were successfully inserted by a CI surgeon into an artificial cochlear model submerged into a temperature-controllable water bath to simulate temporary hypothermia of the inner ear (31°C). Gentle insertions were possible, with an average insertion speed of 0.81 ± 0.14 mm/s. After recovery of body temperature, the desired position shift toward the modiolus was observed in all trials. Angular insertion depth increased by approximately 81.8° ± 23.4°. We demonstrate for the first time that using the body temperature responsive SME for perimodiolar EA positioning is feasible and does not impede a gentle surgical insertion.

First national record of Aedes melanimon (Diptera: Culicidae) in Mexico.

Aedes (Ochlerotatus) melanimon Dyar 1924 has been considered an important pest in agricultural and rural communities. Aedes melanimon is a vector of WEEV and CEV and is a competent laboratory vector of WNV. The known range of Ae. melanimon extends throughout Southwest Canada, part of Central and most of Western USA. Here we report the first record of Ae. melanimon in Mexico, at Ciudad Juárez, Chihuahua. The collect represents the southernmost distributional record for this species. Its indigenous presence in a highly urbanized and dry area was not expected. A permanent surveillance program to detect and determine the species in border-crossing cities is encouraged.

Fenotipo de la enfermedad de Parkinson basado en la edad de inicio en pacientes latinoamericanos: un análisis emparejado / Parkinson’s disease phenotype based on age at onset in Latin American patients: a paired-based analysis

Introducción: Diversos estudios han demostrado una mayor gravedad de sintomatología motora y no motora en pacientes con enfermedad de Parkinson (EP) con edad de inicio tardía comparados con los de inicio intermedio. Decidimos probar estos resultados en una población con EP en Latinoamérica. Pacientes y métodos: Reclutamos a 24 pacientes con EP con una edad de inicio > 65 años (inicio tardío), y cada paciente se emparejó con un control con inicio de la enfermedad entre los 48 y los 60 años (inicio intermedio), emparejados por sexo y duración de la enfermedad (±2 años). Se registraron baterías de pruebas clínicas que evaluaron los síntomas motores –escala unificada de la enfermedad de Parkinson modificada por la Sociedad de Trastornos del Movimiento (MDS-UPDRS)–, los no motores (escala de síntomas no motores), los cognitivos (escala de evaluación cognitiva de Montreal) y la calidad de vida (cuestionario de enfermedad de Parkinson 8). Los grupos se compararon con análisis de regresión logística condicional. Resultados: La edad media de inicio fue de 70,53 ± 3,28 y 53,79 ± 4,96 para los grupos de inicio tardío y de inicio intermedio, respectivamente. No se observaron diferencias significativas en la mayoría de las baterías clínicas cuando se compararon los pacientes con EP según la edad de inicio, con peores puntuaciones significativamente en la MDS-UPDRS, parte III, y en su subdominio de temblor en el grupo de inicio intermedio. Conclusiones: Éste es el primer estudio que informa sobre un fenotipo motor más benigno en pacientes con EP de inicio tardío. A pesar de utilizar una edad de corte más baja para definir el inicio tardío, las características vasculares, epidemiológicas, étnicas y de adhesión al tratamiento también deben considerarse como posibles factores explicativos.(AU)

Introduction: Studies have demonstrated a higher motor and non-motor burden in Parkinson’s disease (PD) patients with old age at onset compared to those with middle age at onset. We decided to test these findings in a Latin American PD population. Patients and methods: We recruited 24 PD patients with age at onset > 65 years, and each patient was matched to 1 control patient with disease onset at ages between 48 and 60 years, matched for gender and disease duration (±2 years). Clinical test batteries that assessed motor (MDS-UPDRS), non-motor (NMSS), cognitive (MoCA), and quality of life (PDQ-8) were recorded. Groups were compared with conditional logistic regression analysis. A comparative post-hoc analysis was also conducted, considering only patients with age at onset > 70 years (n = 11) and their matched controls. Results: Mean age at onset was 70.53 ± 3.28 and 53.79 ± 4.96 for the old-age and middle-age group, respectively. No significant differences were observed in most clinical batteries when comparing PD patients based on age at onset, with worse scores in MDS-UPDRS Part III and Tremor subscore in the middle-age onset group. The post-hoc analysis showed similar results, with non-significantly worse scores in the middle-age onset group. Conclusion: This is the first study reporting a more benign motor phenotype in old-age onset PD patients. Despite the lower cut-off value used for old age onset PD, vascular, epidemiological, ethnic and treatment adherence features must be also considered as potential explicative factors, with further multicenter studies in larger populations needed.(AU)

[Parkinson's disease phenotype based on age at onset in Latin American patients: a paired-based analysis]. / Fenotipo de la enfermedad de Parkinson basado en la edad de inicio en pacientes latinoamericanos: un análisis emparejado.

INTRODUCTION: Studies have demonstrated a higher motor and non-motor burden in Parkinson's disease (PD) patients with old age at onset compared to those with middle age at onset. We decided to test these findings in a Latin American PD population. PATIENTS AND METHODS: We recruited 24 PD patients with age at onset > 65 years, and each patient was matched to 1 control patient with disease onset at ages between 48 and 60 years, matched for gender and disease duration (±2 years). Clinical test batteries that assessed motor (MDS-UPDRS), non-motor (NMSS), cognitive (MoCA), and quality of life (PDQ-8) were recorded. Groups were compared with conditional logistic regression analysis. A comparative post-hoc analysis was also conducted, considering only patients with age at onset > 70 years (n = 11) and their matched controls. RESULTS: Mean age at onset was 70.53 ± 3.28 and 53.79 ± 4.96 for the old-age and middle-age group, respectively. No significant differences were observed in most clinical batteries when comparing PD patients based on age at onset, with worse scores in MDS-UPDRS Part III and Tremor subscore in the middle-age onset group. The post-hoc analysis showed similar results, with non-significantly worse scores in the middle-age onset group. CONCLUSION: This is the first study reporting a more benign motor phenotype in old-age onset PD patients. Despite the lower cut-off value used for old age onset PD, vascular, epidemiological, ethnic and treatment adherence features must be also considered as potential explicative factors, with further multicenter studies in larger populations needed.

TITLE: Fenotipo de la enfermedad de Parkinson basado en la edad de inicio en pacientes latinoamericanos: un análisis emparejado.Introducción. Diversos estudios han demostrado una mayor gravedad de sintomatología motora y no motora en pacientes con enfermedad de Parkinson (EP) con edad de inicio tardía comparados con los de inicio intermedio. Decidimos probar estos resultados en una población con EP en Latinoamérica. Pacientes y métodos. Reclutamos a 24 pacientes con EP con una edad de inicio > 65 años (inicio tardío), y cada paciente se emparejó con un control con inicio de la enfermedad entre los 48 y los 60 años (inicio intermedio), emparejados por sexo y duración de la enfermedad (±2 años). Se registraron baterías de pruebas clínicas que evaluaron los síntomas motores ­escala unificada de la enfermedad de Parkinson modificada por la Sociedad de Trastornos del Movimiento (MDS-UPDRS)­, los no motores (escala de síntomas no motores), los cognitivos (escala de evaluación cognitiva de Montreal) y la calidad de vida (cuestionario de enfermedad de Parkinson 8). Los grupos se compararon con análisis de regresión logística condicional. Resultados. La edad media de inicio fue de 70,53 ± 3,28 y 53,79 ± 4,96 para los grupos de inicio tardío y de inicio intermedio, respectivamente. No se observaron diferencias significativas en la mayoría de las baterías clínicas cuando se compararon los pacientes con EP según la edad de inicio, con peores puntuaciones significativamente en la MDS-UPDRS, parte III, y en su subdominio de temblor en el grupo de inicio intermedio. Conclusiones. Éste es el primer estudio que informa sobre un fenotipo motor más benigno en pacientes con EP de inicio tardío. A pesar de utilizar una edad de corte más baja para definir el inicio tardío, las características vasculares, epidemiológicas, étnicas y de adhesión al tratamiento también deben considerarse como posibles factores explicativos.

Organic matter removal in a simultaneous nitrification-denitrification process using fixed-film system.

Swine wastewater treatment is a complex challenge, due to the high organic matter (OM) and nitrogen (N) concentrations which require an efficient process. This study focused on evaluating two different support media for OM and N removal from an Upflow Anaerobic Sludge Blanket (UASB) reactor fed with swine wastewater. Maximum specific nitrification (MSNA) and denitrification (MSDA) activity test for both biofilm and suspended biomass were carried out using as supports: polyurethane foam (R1) and polyethylene rings (R2). The results showed that R2 system was more efficiently than R1, reaching OM removal of 77 ± 8% and N of 98 ± 4%, attributed to higher specific denitrifying activity recorded (5.3 ± 0.34 g NO3-N/g TVS∙h). Furthermore, 40 ± 5% of the initial N in the wastewater could have been transformed into molecular nitrogen through SND, of which only 10 ± 1% was volatilized. In this sense, MSDA tests indicated that suspended biomass was responsible for at least 70% of N removal and only 20% can be attributed to biofilm. SND could be confirmed with the analysis of microbial diversity, due to the presence of the genus Pseudomonas dominated the prokaryotic community of the system in 54.4%.

Non-PCOS Hyperandrogenic Disorders in Adolescents.

Hyperandrogenism-clinical features resulting from increased androgen production and/or action-is not uncommon in peripubertal girls. Hyperandrogenism affects 3 to 20% of adolescent girls and often is associated with hyperandrogenemia. In prepubertal girls, the most common etiologies of androgen excess are premature adrenarche (60%) and congenital adrenal hyperplasia (CAH; 4%). In pubertal girls, polycystic ovary syndrome (PCOS; 20-40%) and CAH (14%) are the most common diagnoses related to androgen excess. Androgen-secreting ovarian or adrenal tumors are rare (0.2%). Early pubic hair, acne, and/or hirsutism are the most common clinical manifestations, but signs of overt virilization in adolescent girls-rapid progression of pubic hair or hirsutism, clitoromegaly, voice deepening, severe cystic acne, growth acceleration, increased muscle mass, and bone age advancement past height age-should prompt detailed evaluation. This article addresses the clinical manifestations of and management considerations for non-PCOS-related hyperandrogenism in adolescent girls. We propose an algorithm to aid diagnostic evaluation of androgen excess in this specific patient population.

Hydraulic insertions of cochlear implant electrode arrays into the human cadaver cochlea: preliminary findings.

OBJECTIVES: (1) To evaluate the feasibility of a non-invasive, novel, simple insertion tool to perform automated, slow insertions of cochlear implant electrode arrays (EA) into a human cadaver cochlea; (2) to estimate the handling time required by our tool. METHODS: Basic science study conducted in an experimental OR. Two previously anonymized human cadaver heads, three commercially available EAs, and our novel insertion tool were used for the experiments. Our tool operates as a hydraulic actuator that delivers an EA at continuous velocities slower than manually feasible. INTERVENTION(S): the human cadaver heads were prepared with a round-window approach for CI surgery in a standard fashion. Twelve EA insertion trials using our tool involved: non-invasive fixation of the tool to the head; directing the tool to the round window and EA mounting onto the tool; automated EA insertion at approximately 0.1 mm/s driven by hydraulic actuation. Outcome measurement(s): handling time of the tool; post-insertion cone-beam CT scans to provide intracochlear evaluation of the EA insertions. RESULTS: Our insertion tool successfully inserted an EA into the human cadaver cochlea (n = 12) while being attached to the human cadaver head in a non-invasive fashion. Median time to set up the tool was 8.8 (7.2-9.4) min. CONCLUSION: The first insertions into the human cochlea using our novel, simple insertion tool were successful without the need for invasive fixation. The tool requires < 10 min to set up, which is clinically acceptable. Future assessment of intracochlear trauma is needed to support its safety profile for clinical translation.

Acclimation of microorganisms for an efficient production of volatile fatty acids and biogas from mezcal vinasses in a dark fermentation process.

Mezcal is an alcoholic artisanal drink made from agave plants in Mexico. Its production causes the generation of wastewater called vinasses, which are highly polluting residues due to its concentration of organic matter as chemical oxygen demand (COD) (35,000-122,000 mg/L) and acidity (pH < 4). Due to their organic content, these residues can be used in dark fermentation to obtain biogas, which is rich in hydrogen. In this work, the acclimation of inoculum by means of a dark fermentation process, in the presence of toxic compounds from mezcal vinasses was studied. The strategy of increasing the initial concentration of vinasse in each treatment cycle in a sequencing batch reactor (SBR) reactor was applied. It was possible to obtain a maximum biogas production of 984 ± 187 mL/L, from vinasses (18,367 ± 1,200 mg COD/L), with an organic matter removal efficiency of 20 ± 1%. A maximum generation of volatile fatty acids (VFA) of 980 ± 538 mg/L equivalent to a production of 74 ± 21% of the influent concentration and removal rate of organic matter of 1,125 ± 234 mg COD/L d-1 equivalent to a removal efficiency of 20 ± 4% was obtained from vinasses with a concentration of 19,648 ± 1,702 mg COD/L.

The Effect of Ultra-slow Velocities on Insertion Forces: A Study Using a Highly Flexible Straight Electrode Array.

OBJECTIVE: The present study sought to 1) characterize insertion forces resulting from a flexible straight electrode array (EA) inserted at slow and ultra-slow insertion velocities, and 2) evaluate if ultra-slow velocities decrease insertion forces independent of other variables. BACKGROUND: Low insertion forces are desirable in cochlear implant (CI) surgery to reduce trauma and preserve hearing. Recently, ultra-slow insertion velocities (lower than manually feasible) have been shown to produce significantly lower insertion forces using other EAs. METHODS: Five flexible straight EAs were used to record insertion forces into an inelastic artificial scala tympani model. Eleven trial recordings were performed for each EA at five predetermined automated, continuous insertion velocities ranging from 0.03 to 1.6 mm/s. RESULTS: An ultra-slow insertion velocity of 0.03 mm/s resulted in a median insertion force of 0.010 N at 20 mm of insertion depth, and 0.026 N at 24.3 mm-the final insertion depth. These forces represent only 24 to 29% of those measured using 1.6 mm/s. After controlling for insertion depth of the EA into the artificial scala tympani model and trial insertion number, decreasing the insertion velocity from 0.4 to 0.03 mm/s resulted in a 50% decrease in the insertion forces. CONCLUSION: Using the tested EA ultra-slow velocities can decrease insertion forces, independent of variables like insertion depth. Our results suggest ultra-slow velocities can reduce insertion forces at least 60%, compared with humanly feasible continuous velocities (≥0.9 mm/s).

Antibacterial properties of phenothiazine derivatives against multidrug-resistant Acinetobacter baumannii strains.

AIM: As options to treat recalcitrant bacterial infections which are increasingly limited due to multidrug-resistant strains, searching for new, effective antibacterial compounds is necessary. One strategy is to generate treatment alternatives by drug repurposing. METHODS AND RESULTS: In this work, phenotypic microarrays were used for the screening of miscellaneous compounds against the growth and biofilm formation of Acinetobacter baumannii, an important emergent multidrug-resistant opportunistic pathogen. The results showed that the phenothiazine derivatives, such as promethazine, trifluoperazine, thioridazine, and chlorpromazine, inhibited the growth of antibiotic-sensitive and multidrug-resistant strains (showing minimal inhibitory concentrations ranging from 0·05 to 0·6 g l-1 and minimal bactericidal concentrations ranging from 0·1 to 2·5 g l-1 ). All phenothiazine derivatives were active against biofilm cells (with minimal biofilm eradication concentrations ranging from 0·5 to >3 g l-1 ). Chlorpromazine promoted reactive oxigen species (ROS) production, and cell membrane and DNA damage. Chlorpromazine showed synergy with antibiotics such as ceftazidime, meropenem, and colistin and was an effective treatment for experimentally infected Galleria mellonella when combined with ceftazidime. CONCLUSIONS: It was demonstrated that phenothiazine derivatives, especially chlorpromazine, are drugs with attractive antibacterial properties against nosocomial MDR strains of A. baumannii, by generating ROS and cell membrane and DNA damage. SIGNIFICANCE AND IMPACT OF THE STUDY: The present study indicates that repurposing phenothiazine derivatives for treating recalcitrant infections by A. baumannii could be promising.

Reducing Sound Exposure During Ocular Vestibular Evoked Myogenic Potential Testing for Superior Semicircular Canal Dehiscence Syndrome.

BACKGROUND: Ocular vestibular evoked myogenic potentials (oVEMP) testing in response to air-conducted sound (ACS) has excellent sensitivity and specificity for superior semicircular canal dehiscence syndrome (SCDS). However, patients with SCDS may experience vertigo with the test, and recent works recommend minimizing acoustic energy during VEMP testing. PURPOSE: To develop an oVEMP protocol that reduces discomfort and increases safety without compromising reliability. METHODS: Subjects: Fifteen patients diagnosed with SCDS based on clinical presentation, audiometry, standard VEMP testing, and computed tomography (CT) imaging. There were 17 SCDS-affected ears and 13 unaffected ears. In nine (53%) of the SCDS-affected ears surgical repair was indicated, and SCD was confirmed in each. oVEMPs were recorded in response to ACS using 500 Hz tone bursts or clicks. oVEMP amplitudes evoked by 100 stimuli (standard protocol) were compared with experimental protocols with only 40 or 20 stimuli. RESULTS: In all three protocols, oVEMP amplitudes in SCDS-affected ears were significantly higher than in the unaffected ears (p < 0.001). 500 Hz tone bursts evoked oVEMPs with excellent (>90%) sensitivity and specificity in each of the three protocols. However, in the unaffected ears, lowering to 20 stimuli reduced the detection of oVEMP responses in some ears. Following surgical repair, oVEMPs normalized in each of the protocols. CONCLUSION: In oVEMP testing using ACS for SCDS, reducing the number of trials from 100 to 40 stimuli results in a more tolerable and theoretically safer test without compromising its effectiveness for the diagnosis of SCDS. Reducing to 20 stimuli may degrade specificity with clicks.