Automatic jitter measurement in needle-detected motor unit potential trains.

In an active motor unit (MU), the time intervals between the firings of its muscle fibers vary across successive MU activations. This variability is called jitter and is increased in pathological processes that affect the neuromuscular junctions or terminal axonal segments of MUs. Traditionally, jitter has been measured using single fiber electrodes (SFEs) and a difficult and subjective manual technique. SFEs are expensive and reused, implying a potential risk of patient infection; so, they are being gradually substituted by safer, disposable, concentric needle electrodes (CNEs). As CNEs are larger, voltage contributions from individual fibers of a MU are more difficult to detect, making jitter measurement more difficult. This paper presents an automatic method to estimate jitter from trains of motor unit potentials (MUPs), for both SFE and CNE records. For a MUP train, segments of MUPs generated by single muscle fibers (SF MUP segments) are found and jitter is measured between pairs of these segments. Segments whose estimated jitter values are not reliable, according to several SF MUP segment characteristics, are excluded. The method has been tested in several simulation studies that use mathematical models of muscle fiber potentials. The results are very satisfactory in terms of jitter estimation error (less than 10% in most of the cases studied) and mean number of valid jitter estimates obtained per simulated train (greater than 1.0 in many of the cases and less than 0.5 only in the most complicated). A preliminary study with real signals was also performed, using 19 MUP trains from 3 neuropathic patients. Jitter measurements obtained by the automatic method were compared with those extracted from a commercial system (Keypoint) and the edition and supervision of an expert electromyographer. From these measurements 63% were taken from equivalent interval pair sites within the time span of the MUP trains and, as such, were considered as compatible measurements. Differences in jitter of these compatible measurements were very low (mean value of 1.3 µs, mean of absolute differences of 2.97 µs, 25% and 75% percentile intervals of -0.85 and 3.82 µs, respectively). Although new tests with larger number of real recordings are still required, the method seems promising for clinical practice.

Short-Term Effect of Epley Maneuver as Treatment for Subjective Benign Paroxysmal Positional Vertigo.

Subjective Benign Paroxysmal Positional Vertigo (S-BPPV) is an atypical form of BPPV, its treatment is not well characterized and is not well known among otolaryngologists. The main aim of this study was to estimate the short-term efficacy of Epley maneuver as treatment for S-BPPV. This was a prospective study in a secondary care center. We included patients with unilateral S-BPPV demonstrated by negative nystagmus on Dix-Hallpike Maneuver (DHM) but with unilateral vestibular symptoms (dizziness or vertigo). Epley maneuver to the affected side was performed. Patients underwent Dizziness Handicap Inventory (DHI) and at 1-week follow-up, DHI and DHM were repeated. Outcome measures were resolution of symptoms during DHM and improvement of DHI scores. Patients were divided into resolved and unresolved groups according to the absence or presence of symptoms during the 1 week DHM. Wilcoxon-Mann-Whitney and Kruskal-Wallis tests were used, quantitative values were reported as mean and standard deviation. The results included thirteen participants, 12 females and 1 male, mean age 53.31 years (SD ± 15.71). Right ear was involved in 46.15% and left in 53.84%. A total of 46.15% patients (n = 6) had resolution of symptoms. DHI initial score for the resolved group was 34.66 ± 22 and for the unresolved group was 39.71 ± 19.61 (p = 0.568). At 1-week evaluation scores were 19.66 ± 25.05 for the resolved group and 30.28 ± 21.42 for the unresolved group (p = 0.252). DHI improvement was 15.00 ± 23.21 and 9.42 ± 10.17 for each group, respectively (p = 0.943). We concluded the Epley maneuver is an effective short-term treatment for S-BPPV. Half of the patients would need further diagnostic tests.

Acúfeno como síntoma inicial de plasmocitoma de hueso temporal

Resumen Los tumores de base de cráneo son inusuales, entre ellos el plasmocitoma surge de las células plasmáticas y puede ser el precursor del mieloma múltiple. Existen 2 tipos de plasmocitoma: el óseo solitario y el extramedular. Además, el plasmocitoma temporal es aún menos frecuente. El acúfeno puede ser la presentación inicial de estos tumores inusuales. Se presenta caso de una paciente femenina de 74 años, que inicia con acúfeno derecho, así como hipoa-cusia derecha. Acompañado de dolor cervical y limitación de la flexión cervical e inestabilidad. Como único dato a la otoscopia derecha presenta hipervascularidad del promontorio. Se realizan estudios de imagen reportando tumor con erosión ósea de ambas porciones petrosas de hueso temporal, esfenoides y columna cervical. Se realizó una biopsia transesfenoidal reportando plasmocitoma CD 138 positivo. Se inició quimioterapia y radioterapia. El acúfeno unilateral debe estudiarse ampliamente ya que puede ser síntoma de diagnósticos inusuales como neoplasias de base de cráneo.

Abstract Skull-base tumors are unusual, Plasmacytoma arises from plasma cells and could be the precursor of multiple myeloma. There are 2 types of plasmacytoma: solitary bone and extramedullary. Temporal bone plasmacytoma is even more infrequent. Tinnitus could be the initial symptom of this unusual tumors. We present the case of a 74-year-old female patient, who started with right tinnitus as well as right hearing loss. Accompanied by cervical pain and limitation of cervical flexion and instability. As the only data on right otoscopy, there was an hypervascular promontory. Imaging studies were performed reporting tumor with bone erosion of both petrous portions of temporal bone, sphenoid, and cervical spine. A transsphenoidal biopsy was performed, reporting positive CD 138 plasmacytoma. Chemotherapy and radiotherapy were indicated. Unilateral tinnitus should be fully studied because it might be a symptom of unusual diagnoses such as skull base neoplasms.

Adaptation and validation of the chronic otitis media questionnaire 12 (COMQ-12) in the Mexican Spanish language (COMQ-12-Mx).

Background: Chronic otitis media (COM) questionnaire 12 (COMQ-12) is a specific-disease tool that evaluates COM patients.Objective: To validate COMQ-12 in the Mexican Spanish language (COMQ-12-Mx).Materials and methods: Mexican Spanish-speaking healthy volunteers and COM patients who attended a Secondary Care Center from May 2019 to October 2019. The COMQ-12 in Mexican Spanish was obtained by translation and back translation from an English-Spanish translator. All participants completed the COMQ-12-Mx questionnaire. COM patients were included regardless of their COM status. Control group completed the questionnaire twice. Participants were categorized into three groups: group 1 (COM), group 2 (volunteers first test) and group 3 (volunteers retest). Cronbach's alpha was used for internal consistency, Spearman's rank correlation coefficient was used for test-retest reliability and Mann-Whitney U test compared groups.Results: We included 78 Mexican Spanish-speaking participants (COM n = 37, healthy volunteers n = 41), 51 females and 27 males, mean age was 39.67 years (SD ± 18.32). Group 1 COMQ-12-Mx score was 22.108 ± 11.79, group 2 score was 3.561 ± 4.399 (p ≤ .001) and group 3 score was 3.683 ± 4.435. Cronbach's alpha was 0.828 and test-retest reliability achieved a 0.928 outcome.Conclusions: COMQ-12-Mx is a valid and reliable tool to evaluate quality life in Mexican Spanish-speaking patients with COM.

Coccidiosis y amibiasis intestinal en niños de edad escolar de un distrito de Lambayeque, Perú / Intestinal coccidiosis and amebiasis in school age children of a district in Lambayeque, Peru

Objetivos: Determinar la prevalencia y los factores asociados a coccidiosis y amibiasis intestinal en niños de edad escolar del distrito de Chongoyape, Chiclayo, Perú. Material y métodos: Estudio transversal de tipo relacional entre noviembre del 2014 y enero del 2015 en 133 escolares. Para recolectar la información sociodemográfica y de saneamiento se usó un cuestionario estructurado. La detección de los parásitos se realizó en muestras seriadas de heces. Para los coccidios intestinales se realizó examen microscópico directo (EMD), técnica ácido resistente modificada (TARM) y ELISA coproantígenos para Cryptosporidium spp., mientras que para la amibiasis se usó EMD y ELISA coproantígenos para Entamoeba hystolitica. Resultados: El 6,8% (9/133) de la muestra presentó coccidiosis intestinal, 3,8% (5/133) con Cryptosporidium spp., y 3,0% (4/133) con Cyclospora cayetanensis. No se detectó Cystoisospora belli. El 4,5% (6/133) de la muestra presentó E. histolytica. El factor asociado en ambas parasitosis fue el consumo de agua insalubre (p=0,001 y p=0,026 respectivamente), mientras que el contacto con animales se asoció a la coccidiosis intestinal (p=0,013). Conclusiones: La coccidiosis y la amibiasis intestinal son frecuentes en niños de la población estudiada, evidenciando su importancia como problema de salud pública y la necesidad de un diagnóstico específico y rutinario en las instituciones de salud de la región. (AU)

Objectives: To determine the prevalence of and risk factors for intestinal coccidiosis and amebiasis in school-age children in the district of Chongoyape, Chiclayo, Peru. Methods: Cross-sectional study carried-out between November 2014 and January 2015 among 133 school-aged children. A structures questionnaire collected socio-demographic and sanitation information. Serial stool samples were required, which were processed under direct microscopy, modified acid-fast staining and ELISA to detect antigens of Cryptosporidium spp, while direct microscopy and ELISA were used to detect Entamoeba hystolitica. Results: 6.8% (9/133) of the samples were positive for coccidian parasites, 3.8% (5/133) were positive for Cryptosporidium and 3% (4/133) for Cyclospora cayetanensis, no Cystoisospora belli was identified. E. hystolitica was found in 4.5% (6/133) samples. Drinking non-potable water was a risk factor for getting both infections, while animal contact was associated with getting a coccidian parasite (p=0.013). Conclusions: Both coccidian and intestinal amebas are frequent protozoan infections in this population. These parasites are public health problem that require routine and specific diagnostic methods in the region. (AU)

Efecto temprano y tardío de la prueba cutánea con Blatella germanica (Bg) y/o Periplaneta americana (Pa) sobre el volumen espiratorio forzado y el flujo espiratorio máximo en niños con alergia respiratoria / Early and late effect of the skin prick test with cockroach (Blatella germanica and/or periplaneta american) on the forced expiratory volume and peak expiration flow in children with respiratory allergy

Introducción. Se ha demostrado que los alergenos de cucaracha sensibilizan a los niños atópicos y frecuentemente predisponen al desarrollo de asma grave a temprana edad. Objetivo: evaluar los cambios tempranos como tardíos sobre el volumen espiratorio forzado (VEF1) y flujo espiratorio máximo (FEM) en niños con alergia respiratoria y prueba cutánea (PC) positiva a antígeno de cucaracha.Material y métodos. Estudio prospectivo longitudinal cruzado doble ciego controlado en niños de 6 a 16 años de edad con un VEF1 y FEM basal mayor de 80 por ciento de su predicho y PC positiva exclusivamente a Blattella germanica (Bg) y/o Periplaneta americana (Pa). En diferentes momentos se midió el VEF1 y FEM antes de la PC con Ba y/o Pa, o con placebo (solución glicerinada) y se realizaron espirometrías y flujimetrías a los 15 min 2, 4, 6, 8, 12, 24 y 48 horas. Análisis estadístico: se utilizó t de Student para muestras pareadas.Resultados. Se estudiaron 30 pacientes con PC positiva a alergeno de cucaracha: 21 hombres y 9 mujeres; 20 presentaron PC positiva a Bg y Pa, 8 a Bg y 2 a Pa. Catorce de 30 pacientes presentaron caída del VEF1 a los 15 min, 13 de ellos la presentaron también a las 6, 12 y 24 horas después de la PC con antígeno. Sólo 3 pacientes presentaron esa caída a los 15 min de la prueba con placebo. En todas las mediciones del grupo estudiado con alergeno de cucaracha se encontró caída del VEF1 mayor de 15 por ciento (P=0.02). En el FEM no se encontró diferencia estadística significativa en ninguno de los grupos (P=0.5).Conclusiones. La medición del VEF1 fue más eficaz para detectar caídas, tanto tempranas como tardías. Por el contrario el FEM no fue sensible para detectar cambios en la función pulmonar después de reto cutáneo con alergenos de cucaracha.