Role of Lateral Ankle Ligaments in Vertical Stability of the Fibula: A Cadaveric Model.

BACKGROUND: In unstable ankle fractures, the role of the deltoid and syndesmosis ligaments has been widely studied. However, it is uncertain what the importance of the lateral ankle ligament complex (LALC) is in the vertical stability of the fibula. Given its anatomical position, it should prevent the proximal translation of the fibula. This study aims to evaluate the role of the LALC in stabilizing the fibula in the vertical plane. METHODS: Eleven below-knee cadaveric specimens were used in this study. Proximal traction of the fibula was performed by applying 50 N in the intact state and after sequential transection of the syndesmotic ligaments, anterior talofibular ligament (ATFL), and the calcaneofibular ligament (CFL). At each stage, the proximal displacement of the fibula was measured. One-way repeated measures analysis of variance with post hoc Bonferroni correction was carried out to determine any significant differences between the groups. A P value <.05 was considered statistically significant. RESULTS: The vertical displacement of the fibula in the intact state, and after sequential transection of syndesmotic ligaments, ATFL, and CFL was 1.96 ± 1.19 mm, 3.96 ± 1.33 mm, 5.9 ± 1.73 mm, and 10.22 ± 2.76 mm, respectively. There was no significant difference in the proximal displacement of the fibula between the intact and the syndesmotic ligaments groups (P < .05). However, when the syndesmotic ligaments were transected in conjunction with ATFL ± CFL, a significant difference was observed compared to the intact state (P < .001). CONCLUSION: The complete disruption of syndesmotic ligaments did not significantly increase the proximal displacement of the fibula. However, when the ATFL ± CFL were additionally disrupted, there was a significant increase in the vertical translation of the fibula. CLINICAL RELEVANCE: To our knowledge, this is the first study describing that LALC plays a paramount role in the vertical stability of the fibula. Concomitant syndesmosis and LALC should be suspected in an axially unstable fibular fracture with a significant proximal displacement.

[Obesity, weight-related stigma and its association with the perception of quality of life in Chilean university students]. / Obesidad, estigma relacionado con el peso y su asociación con la percepción de la calidad de vida en estudiantes universitarios chilenos.

Introduction: Introduction: little attention has been paid to the effect of exposure to weight-related stigma on the quality of life of young Chileans with obesity. Objective: to identify the prevalence of weight-related stigma and to analyze its association with obesity and the perception of quality of life in university students from Valparaíso, Chile. Methods: correlational type study and cross-sectional design. Two hundred and sixty-two university students participated, from 18 to 29 years old, matriculated in the Faculty of Health Sciences of a public university in Valparaíso, Chile. Quality of life was assessed with the WHOQOL-BREF scale, weight-related stigma with the Brief Stigmatizing Situations Inventory (SSI), and nutritional status with body mass index (BMI) classification. The application of the questionnaires was on-line and the answers were anonymous. Multiple logistic regression models were used to evaluate the association between the variables, adjusted for gender and age. Results: the prevalence of stigma related to weight was 13,2 % in eutrophic, 24,4 % in overweight and 68,0 % in obese. Weight-related stigma, rather than obesity itself, is associated with poorer perceived physical health (OR: 4.30; 95 % CI: 2.10-8.80), psychological health (OR: 4.51; 95 % CI: 2.20-9.26), social relationships (OR: 3.21; 95 % CI: 1.56-6.60) and environment (OR: 2.86; 95 % CI: 1.33-6.14). Conclusion: students exposed to stigmatizing situations related to weight had a worse perception of their quality of life compared to those not stigmatized.

Introducción: Introducción: el efecto de la exposición al estigma relacionado en la calidad de vida de los jóvenes con obesidad ha recibido poca atención. Objetivo: identificar la prevalencia de estigma relacionado con el peso y analizar su asociación con la obesidad y la percepción de la calidad de vida en estudiantes universitarios de Valparaíso, Chile. Metodología: estudio de tipo correlacional y diseño transversal. Participaron 262 estudiantes universitarios, de 18 a 29 años de edad, matriculados en la Facultad de Ciencias de la Salud de una universidad pública de Valparaíso, Chile. La calidad de vida se evaluó con la escala WHOQOL-BREF; el estigma relacionado con el peso, con el Inventario breve de Situaciones Estigmatizantes (SSI); y el estado nutricional, con la clasificación del índice de masa corporal (IMC). La aplicación de los cuestionarios fue en línea y las respuestas fueron anónimas. Se realizaron modelos de regresión logística múltiple para evaluar la asociación entre las variables, ajustados por sexo y edad. Resultados: la prevalencia de estigma relacionado con el peso fue del 13,2 % en eutróficos, 24,4 % en sobrepesos y 68,0 % en obesos. El estigma relacionado con el peso, más que la obesidad en sí misma, se asoció con una peor salud física percibida (OR: 4,30; 95 % IC: 2,10-8,80), salud psicológica (OR: 4,51; 95 % IC: 2,20-9,26), relaciones sociales (OR: 3,21; 95 % IC: 1,56-6,60) y ambiente (OR: 2,86; 95 % IC: 1,33-6,14). Conclusiones: los estudiantes expuestos a situaciones estigmatizantes relacionadas con el peso tuvieron una peor percepción de su calidad de vida en comparación con aquellos no estigmatizados.

Ludwig's angina complicated with a massive necrotizing fasciitis caused by an unusual pathogen: Bacillius spp

Ludwig's angina and necrotizing fasciitis are aggressive infectious manifestations that can present in the cervicofacial region. The severity of these entities depends, up to some extent, to the immunological state of the patient. Diabetes mellitus alters the immune system, allowing maxillofacial infections to progress aggressively. Bacillius spp. is a group of typically innocuous bacteria; however, they can unchain relevant infectious pathologies in immunocompromised patients. The purpose of this study is to describe a case of an uncontrolled diabetic patient with a Ludwig's angina which progressed to a massive necrotizing fasciitis caused by bacillius spp. Explaining the severity of this class of infections and the special attention that should be paid to this type of case; Furthermore, when the culture reveals pathogens that are usually not involved in the development of this class of conditions.

Actitudes hacia la muerte expresadas por jóvenes en contexto COVID-19 en la región de Tarapacá

Esta investigación analizó las actitudes hacia la muerte expresadas por un grupo de adultos jóvenes en contexto COVID-19. Los participantes fueron 10 jóvenes residentes en la región de Tarapacá (60% mujeres, 40% hombres) entre 18 a 29 años. La metodología tuvo un enfoque mixto de preponderancia cualitativa y diseño secuencial. En la primera etapa, se administró el Perfil Revisado de Actitudes hacia la muerte [PAM-R] para medir cinco actitudes: Miedo a la muerte; Evitación de la muerte; Aceptación de acercamiento; Aceptación de escape; y Aceptación neutral. Posteriormente, se aplicaron entrevistas semiestructuradas que profundizaron los resultados, mediante la exploración de las percepciones, emociones y pensamientos de los participantes durante la pandemia. Finalmente, se triangularon los datos cuantitativos y cualitativos para obtener una mayor validez. Los resultados señalan a estas actitudes como un fenómeno contextual, cuya expresión depende de diversos elementos personales y del entorno, siendo los más importantes los miedos asociados a familiares. En jóvenes, la muerte fue comprendida como una realidad lejana. Esto influyó en una alta neutralidad y bajo miedo a la muerte propia. El contexto COVID-19 actuó como un factor influyente en las actitudes, particularmente en el miedo al contagio o a la posibilidad de morir. Si bien los jóvenes reconocieron la peligrosidad del virus, sus necesidades emocionales-afectivas se vislumbraron como problemas más urgentes. Por lo tanto, los miedos en contexto COVID-19 no evitaron la exposición al contagio en compañía de amigos. Estas conductas fueron significadas como medidas de autocuidado psicológico, particularmente en jóvenes con Aceptación de Escape.

This research analyzed the attitudes towards death expressed by a group of young adults in a COVID-19 context. The participants were 10 young residents in the Tarapacá region (60% women, 40% men) between 18 and 29 years old. The methodology had a mixed approach of qualitative preponderance and sequential design. First, the Death Attitude Profile-Revised [DAP-R] was administered to measure five attitudes: Fear of Death, Death Avoidance, Approach Acceptance, Escape Acceptance, and Neutral Acceptance. Subsequently, semi-structured interviews were applied that deepened the results, by exploring the perceptions, emotions and thoughts of the participants during the pandemic. Finally, the quantitative and qualitative data were triangulated to obtain greater validity. The results point to these attitudes as a contextual phenomenon, the expression of which depends on various personal and environmental elements, the most important being the fears associated with family members. In young people, death was understood as a distant reality. This influenced a high neutrality and low fear of own death. The COVID-19 context acted as an influencing factor in attitudes, particularly in fear of contagion or the possibility of dying. Although the young people recognized the dangerousness of the virus, their emotional-affective needs were seen as more urgent problems. Therefore, fears in the COVID-19 context did not prevent exposure to contagion in the company of friends. These behaviors were signified as measures of psychological self-care, particularly in young people with Escape Acceptance.

Este estudo teve como objetivo analisar as atitudes de um grupo de jovens adultos em relação a morte no contexto de COVID-19. Nela participaram 10 jovens que vivem na região de Tarapacá (60% mulheres, 40% homens) os quais tinham entre 18 e 29 anos. A metodologia da pesquisa teve uma abordagem mista de preponderância qualitativa e desenho de investigação sequencial. Na primeira etapa, foi administrado o Perfil Revisado de Atitudes em Relação a Morte [PAM-R] para medir cinco atitudes: Medo da morte; Evitar a morte; Aceitação de abordagem; Aceitação de fuga; e aceitação neutra. Posteriormente, foram aplicadas entrevistas semi-estruturadas que aprofundaram os resultados, explorando as percepções, emoções e pensamentos dos participantes durante a pandemia. Por fim, os dados quantitativos e qualitativos foram triangulados para obter maior validade. Os resultados apontam essas atitudes como um fenômeno contextual, cuja expressão depende de diversos elementos pessoais e do meio ambiente, sendo o mais importante deles, os medos associados aos parentes. Nos jovens, a morte era entendida como uma realidade distante. Isso influenciou uma alta neutralidade e pouco medo da propia morte. O contexto de COVID-19 atuou como um fator influente nas atitudes, particularmente no medo de contágio ou na possibilidade de morrer. Enquanto os jovens reconheciam o perigo do vírus, suas necessidades emotivas e afetivas eram vistas como problemas mais urgentes. Portanto, os temores no contexto de COVID-19 não impediram a exposição ao contágio na companhia de amigos. Esses comportamentos foram considerados como medidas de autocuidado psicológico, particularmente em jovens com Aceitação da Fuga da morte.

Actitudes hacia la muerte expresadas por jóvenes en contexto COVID-19 en la región de Tarapacá / The death attitudes expressed by young adults from Tarapacá region in COVID-19 context / Atitudes de jovens da região de Tarapacá em relação a morte no contexto de COVID-19

Resumen Esta investigación analizó las actitudes hacia la muerte expresadas por un grupo de adultos jóvenes en contexto COVID-19. Los participantes fueron 10 jóvenes residentes en la región de Tarapacá (60% mujeres, 40% hombres) entre 18 a 29 años. La metodología tuvo un enfoque mixto de preponderancia cualitativa y diseño secuencial. En la primera etapa, se administró el Perfil Revisado de Actitudes hacia la muerte [PAM-R] para medir cinco actitudes: Miedo a la muerte; Evitación de la muerte; Aceptación de acercamiento; Aceptación de escape; y Aceptación neutral. Posteriormente, se aplicaron entrevistas semiestructuradas que profundizaron los resultados, mediante la exploración de las percepciones, emociones y pensamientos de los participantes durante la pandemia. Finalmente, se triangularon los datos cuantitativos y cualitativos para obtener una mayor validez. Los resultados señalan a estas actitudes como un fenómeno contextual, cuya expresión depende de diversos elementos personales y del entorno, siendo los más importantes los miedos asociados a familiares. En jóvenes, la muerte fue comprendida como una realidad lejana. Esto influyó en una alta neutralidad y bajo miedo a la muerte propia. El contexto COVID-19 actuó como un factor influyente en las actitudes, particularmente en el miedo al contagio o a la posibilidad de morir. Si bien los jóvenes reconocieron la peligrosidad del virus, sus necesidades emocionales-afectivas se vislumbraron como problemas más urgentes. Por lo tanto, los miedos en contexto COVID-19 no evitaron la exposición al contagio en compañía de amigos. Estas conductas fueron significadas como medidas de autocuidado psicológico, particularmente en jóvenes con Aceptación de Escape.

Abstract This research analyzed the attitudes towards death expressed by a group of young adults in a COVID-19 context. The participants were 10 young residents in the Tarapacá region (60% women, 40% men) between 18 and 29 years old. The methodology had a mixed approach of qualitative preponderance and sequential design. First, the Death Attitude Profile-Revised [DAP-R] was administered to measure five attitudes: Fear of Death, Death Avoidance, Approach Acceptance, Escape Acceptance, and Neutral Acceptance. Subsequently, semi-structured interviews were applied that deepened the results, by exploring the perceptions, emotions and thoughts of the participants during the pandemic. Finally, the quantitative and qualitative data were triangulated to obtain greater validity. The results point to these attitudes as a contextual phenomenon, the expression of which depends on various personal and environmental elements, the most important being the fears associated with family members. In young people, death was understood as a distant reality. This influenced a high neutrality and low fear of own death. The COVID-19 context acted as an influencing factor in attitudes, particularly in fear of contagion or the possibility of dying. Although the young people recognized the dangerousness of the virus, their emotional-affective needs were seen as more urgent problems. Therefore, fears in the COVID-19 context did not prevent exposure to contagion in the company of friends. These behaviors were signified as measures of psychological self-care, particularly in young people with Escape Acceptance.

Resumo Este estudo teve como objetivo analisar as atitudes de um grupo de jovens adultos em relação a morte no contexto de COVID-19. Nela participaram 10 jovens que vivem na região de Tarapacá (60% mulheres, 40% homens) os quais tinham entre 18 e 29 anos. A metodologia da pesquisa teve uma abordagem mista de preponderância qualitativa e desenho de investigação sequencial. Na primeira etapa, foi administrado o Perfil Revisado de Atitudes em Relação a Morte [PAM-R] para medir cinco atitudes: Medo da morte; Evitar a morte; Aceitação de abordagem; Aceitação de fuga; e aceitação neutra. Posteriormente, foram aplicadas entrevistas semi-estruturadas que aprofundaram os resultados, explorando as percepções, emoções e pensamentos dos participantes durante a pandemia. Por fim, os dados quantitativos e qualitativos foram triangulados para obter maior validade. Os resultados apontam essas atitudes como um fenômeno contextual, cuja expressão depende de diversos elementos pessoais e do meio ambiente, sendo o mais importante deles, os medos associados aos parentes. Nos jovens, a morte era entendida como uma realidade distante. Isso influenciou uma alta neutralidade e pouco medo da propia morte. O contexto de COVID-19 atuou como um fator influente nas atitudes, particularmente no medo de contágio ou na possibilidade de morrer. Enquanto os jovens reconheciam o perigo do vírus, suas necessidades emotivas e afetivas eram vistas como problemas mais urgentes. Portanto, os temores no contexto de COVID-19 não impediram a exposição ao contágio na companhia de amigos. Esses comportamentos foram considerados como medidas de autocuidado psicológico, particularmente em jovens com Aceitação da Fuga da morte.

Eritema multiforme como manifestación paraneoplásica de un adenocarcinoma de colon / Erythema multiform as a paraneoplastic manifestation of a colon adenocarcinoma

RESUMEN: El eritema multiforme es una enfermedad autoinmune vesicular-ampollosa y autolimitada, se presenta de forma aguda afectando la piel y mucosa. En 2015, Lee E. y Freer J., incluyeron esta enfermedad dentro de los síndromes dermatológicos paraneoplásicos, pero actualmente no existen muchas publicaciones de esta entidad como manifestación a una neoplasia subyacente. El objetivo de esta investigación es presentar el eritema multiforme como una manifestación paraneoplásica inusual. En este caso una paciente de 64 años de edad que cursaba con adenocarcinoma de colon exhibió el eritema multiforme oral; cuyas manifestaciones bucales involucionaron gracias a la farmacoterapia local y sistémica en conjunto con la excéresis de la lesión cancerosa en el colon. Es importante reconocer la presencia de eritema multiforme como una manifestación paraneoplásica cuando no se exhiben los factores etiológicos frecuentes de esta patología y, por lo tanto, centrarse en la búsqueda subyacente de neoplasias malignas que no son muy evidentes.

ABSTRACT: Erythema multiforme is a self-limiting, blistering, autoimmune disease that presents acutely, affecting the skin and mucosa. In 2015, Lee E. and Freer J. included this disease in paraneoplastic dermatological syndromes, but there are currently not many publications about this entity as a manifestation of an underlying malignancy. The objective of this research is to present the erythema multiforme as an unusual paraneoplastic manifestation. In this case, a female 64-year-old patient with colon adenocarcinoma exhibited oral multiform erythema; whose oral manifestations regressed thanks to local and systemic pharmacotherapy in conjunction with the exeresis of the cancerous lesion in the colon. It is important to recognize the presence of erythema multiforme as a paraneoplastic manifestation when the frequent etiological factors of this pathology are not exhibited and, therefore, to focus on the underlying search for malignant neoplasms that are not very evident.

Submalar fat pad removal for esthetic purposes: A systematic approach.

OBJECTIVE: Submalar fat pad removal for esthetic purposes has been performed as a routine in the last decades. However, several factors have not been properly analyzed and studied. In order to address this problem, the purpose of this study is to describe clinical parameters to be taken into account when analyzing potential patients as well as a systematic approach during the pre, intra and postoperative stages. MATERIALS AND METHODS: Patients complaining of cheek fullness were evaluated to determine if they were good candidates for the procedure. Eligible patients underwent the same patient selection criteria and pre, intra and post-surgical protocol. RESULTS: A total of 44 patients were selected. 40 females and 4 males, with a mean age of 25.4 years. The bilaterally excised buccal fat pads had an average weight of 4.3 gs. There was only 1 complication (unilateral emphysema), during the immediate postoperative phase. CONCLUSIONS: Submalar fat pad removal is an effective technique for refining the facial silhouette that should be reserved only for patients with increased buccal fat pad volume or its pseudoherniation. Performing the surgery following the protocol established in our study can allow the surgeon to achieve more reliable intra and postoperative outcomes.

A Mesocosm Experiment in Ecological Physiology: The Modulation of Energy Budget in a Hibernating Marsupial under Chronic Caloric Restriction.

AbstractDuring the past 60 years, mammalian hibernation (i.e., seasonal torpor) has been interpreted as a physiological adaptation for energy economy. However, direct field comparisons of energy expenditure and torpor use in hibernating and active free-ranging animals are scarce. Here, we followed the complete hibernation cycle of a fat-storing hibernator, the marsupial Dromiciops gliroides, in its natural habitat. Using replicated mesocosms, we experimentally manipulated energy availability and measured torpor use, hibernacula use, and social clustering throughout the entire hibernation season. Also, we measured energy flow using daily food intake, daily energy expenditure (DEE), and basal metabolic rate (BMR) in winter. We hypothesized that when facing chronic caloric restriction (CCR), a hibernator should maximize torpor frequency to compensate for the energetic deficit, compared with individuals fed ad lib. (controls). However, being torpid at low temperatures could increase other burdens (e.g., cost of rewarming, freezing risks). Our results revealed that CCR animals, compared with control animals, did not promote heat conservation strategies (i.e., clustering and hibernacula use). Instead, they gradually increased torpor frequency and reduced DEE and, as a consequence, recovered weight at the end of the season. Also, CCR animals consumed food at a rate of 50.8 kJ d-1, whereas control animals consumed food at a rate of 98.4 kJ d-1. Similarly, the DEE of CCR animals in winter was 47.3±5.64 kJ d-1, which was significantly lower than control animals (DEE=88.0±5.84 kJ d-1). However, BMR and lean mass of CCR and control animals did not vary significantly, suggesting that animals maintained full metabolic capacities. This study shows that the use of torpor can be modulated depending on energy supply, thus optimizing energy budgeting. This plasticity in the use of heterothermy as an energy-saving strategy would explain the occurrence of this marsupial in a broad latitudinal and altitudinal range. Overall, this study suggests that hibernation is a powerful strategy to modulate energy expenditure in mammals from temperate regions.

Treatment of Severe Rigid Posttraumatic Equinus Deformity With Gradual Deformity Correction and Arthroscopic Ankle Arthrodesis.

BACKGROUND: Posttraumatic ankle equinus is associated with rigid deformity, poor skin condition, and multiple prior surgeries. Open acute correction has been described using osteotomies, talectomy, and arthrodesis, but concerns exist about skin complications, neurologic alterations, secondary limb discrepancy, and bone loss. Gradual correction using a multiplanar ring fixator and arthroscopic ankle arthrodesis (AAA) may decrease these complications. METHODS: We retrospectively reviewed patients undergoing correction of posttraumatic rigid equinus with at least 1 year of follow-up after frame removal. The procedure consisted of percutaneous Achilles lengthening, gradual equinus correction using a multiplanar ring fixator, and AAA retaining the fixator in compression with screw augmentation. Frame removal depended on signs of union on the computed tomography scan. Visual analog scale (VAS) and Foot Function Index (FFI) scores were assessed as well as preoperative and postoperative x-rays. Complications were noted throughout the follow-up period. RESULTS: Five patients were treated with a mean age of 35 years and mean follow-up of 31 months. Deformities were gradually corrected into a plantigrade foot over an average duration of 6 weeks. Union was achieved in all patients with a mean time of an additional 25 weeks, for a mean total frame time of 31 weeks. The mean preoperative tibiotalar angle was 151 degrees and was corrected to 115 degrees. FFI score improved from a mean of 87 to 24 and VAS from 8 to 2. CONCLUSION: Posttraumatic rigid equinus can be treated effectively using gradual correction followed by integrated AAA in a safe and reproducible manner. Patients in this series had excellent functional, radiological, and satisfaction results. LEVEL OF EVIDENCE: Level IV, retrospective case series.

Epiplating in Auricular Defects as a Facial Reconstruction Method: Case Series.

The aim of this study is to report on the use of the Epiplating system (Medicon, Tuttlingen, Germany) for the management of craniofacial deformities for optimal functional and esthetic facial reconstruction. The present series of cases comprises 3 patients diagnosed with congenital auricular agenesis who required correction of the auricular defect with osseointegrated implants from the Epiplating system. The implants were left to integrate for a period of 2 to 12 weeks, followed by placement of an implant-retained prosthesis. The criteria for success of the prosthesis include overall stability and function, symmetry, position, and patient acceptance. The implants achieved anchorage, and none showed failure during the study period. The cosmetic results and patient acceptance were very satisfactory, with no postoperative and/or soft tissue complications. Therefore, the survival rate was 100%. This study concludes that the Epiplating system allows optimal functional and esthetic facial reconstruction for the management of craniofacial deformities, as the combination of art and science allows individualized adaptations to improve the quality of life of patients.

The immediate effect of soft tissue manual therapy intervention on lung function in severe chronic obstructive pulmonary disease.

BACKGROUND AND OBJECTIVE: In chronic obstructive pulmonary disease (COPD), accessory respiratory muscles are recruited as a compensatory adaptation to changes in respiratory mechanics. This results in shortening and overactivation of these and other muscles. Manual therapy is increasingly being investigated as a way to alleviate these changes. The aim of this study was to measure the immediate effect on lung function of a soft tissue manual therapy protocol (STMTP) designed to address changes in the accessory respiratory muscles and their associated structures in patients with severe COPD. METHODS: Twelve medically stable patients (n=12) with an existing diagnosis of severe COPD (ten: GOLD Stage III and two: GOLD Stage IV) were included. Residual volume, inspiratory capacity and oxygen saturation (SpO2) were recorded immediately before and after administration of the STMTP. A Student's t-test was used to determine the effect of the manual therapy intervention (P<0.05). RESULTS: The mean age of the patients was 62.4 years (range 46-77). Nine were male. Residual volume decreased from 4.5 to 3.9 L (P=0.002), inspiratory capacity increased from 2.0 to 2.1 L (P=0.039) and SpO2 increased from 93% to 96% (P=0.001). CONCLUSION: A single application of an STMTP appears to have the potential to produce immediate clinically meaningful improvements in lung function in patients with severe and very severe COPD.

Determination of changes in the metabolic profile of avocado fruits (Persea americana) by two CE-MS approaches (targeted and non-targeted).

A CZE method with two different MS detection conditions (MRM and Full Scan) was developed to determine qualitative and quantitative changes in the metabolic profile of avocado fruits (Persea americana). LODs in MRM approach were found between 20.1 and 203.0 ppb for abscisic acid and perseitol, respectively, whilst in Full Scan, varied within the range 0.22­1.90 ppm for the same metabolites. The RSDs for reproducibility test did not exceed 11.45%. The two MS approaches were used to quantify 10 metabolites (phenolic acids, flavonoids, a carbohydrate, an organic acid, a vitamin and a phytohormone) in 18 samples of avocado at different ripening states, and the achieved results were compared. Perseitol, quinic, chlorogenic, trans-cinnamic, pantothenic and abscisic acids, as well as epicatechin and catechin decreased during the ripening process, whereas ferulic and p-coumaric acids showed the opposite trend. Moreover, some other unknown compounds whose concentration changed largely during ripening were also studied by MS/MS and QTOF MS to get a tentative identification.

Merging a sensitive capillary electrophoresis-ultraviolet detection method with chemometric exploratory data analysis for the determination of phenolic acids and subsequent characterization of avocado fruit.

Herein we present the development of a powerful CE-UV method able to detect and quantify an important number of phenolic acids in 13 varieties of avocado fruits at 2 ripening stages. All the variables involved in CE separation were exhaustively optimized and the best results were obtained with a capillary of 50 µm i.d. × 50 cm effective length, sodium tetraborate 40 mM at a pH of 9.4, 30 kV, 25 °C, 10s of hydrodynamic injection (0.5 psi) and UV detection at 254 nm. This optimal methodology was fully validated and then applied to different avocado samples. The number of phenolic acids determined varied from 8 to 14 compounds; in general, they were in concentrations ranging from 0.13 ppm to 3.82 ppm, except p-coumaric, benzoic and protocatechuic acids, which were found at higher concentrations. Principal component analysis (PCA) was applied to highlight the differences between varieties and ripening degrees, looking for the most influential analytes.