Effect of antioxidant supplementation on the auditory threshold in sensorineural hearing loss: a meta-analysis

Introduction

Hearing loss is conceptualized as any impairment of the ability to hear and/or detect speech or environment sounds, regardless of cause, type, or degree. It may occur at different stages of life; during pregnancy or childbirth, in childhood, adulthood or old age. It should be noted that aging is the most common cause of sensorineural hearing loss followed by noise-induced hearing loss, and both are closely related to the formation of reactive oxygen species. Dietary antioxidant supplementation has been employed as a therapeutic strategy to prevent and/or delay the risks of major human diseases.

Evaluation of green extraction methods on bioactive compounds and antioxidant capacity from Bougainvillea glabra bracts

Bougainvillea glabra is a native plant of South America, and its bracts are still an underexploited source of betalains and phenolic compounds. Microwave (MAE), ultrasound (UAE), conventional aqueous and ethanolic exhaustive extractions were used for the recovery of total phenolic compounds (TPC) and betalains from B. glabra bracts. The highest yields of TPC, betalains, and antioxidant capacity by ABTS were obtained by ethanolic exhaustive extraction followed by MAE at 100 and 600 W. Deoxyribose protection assay measurement by hydroxyl radical scavenging showed high values for extracts obtained by exhaustive extraction and MAE, ranging from 89% to 83%, indicating a high capacity to capture hydroxyl radicals. Agarose gel electrophoresis assay showed that the extracts obtained by UAE, conventional aqueous, and ethanolic extraction were able to protect DNA from free radicals and did not show pro-oxidant effect. Seventeen phenolic compounds and seventeen betalains were identified by HPLC/MS in the extract of B. glabra bracts obtained by exhaustive extraction, composed mainly of kaempferol derivatives (76.5%) and acylated betalains (71.0%), respectively. The results suggest that MAE may be an alternative to recover betalains and phenolic compounds from B. glabra bracts due to the lower extraction times and the absence of organic solvent.     

Barn owl feathers as biomonitors of mercury: sources of variation in sampling procedures

Given their central role in mercury (Hg) excretion and suitability as reservoirs, bird feathers are useful Hg biomonitors. Nevertheless, the interpretation of Hg concentrations is still questioned as a result of a poor knowledge of feather physiology and mechanisms affecting Hg deposition. Given the constraints of feather availability to ecotoxicological studies, we tested the effect of intra-individual differences in Hg concentrations according to feather type (body vs. flight feathers), position in the wing and size (mass and length) in order to understand how these factors could affect Hg estimates. We measured Hg concentration of 154 feathers from 28 un-moulted barn owls (Tyto alba), collected dead on roadsides. Median Hg concentration was 0.45 (0.076–4.5) mg kg^?1 in body feathers, 0.44 (0.040–4.9) mg kg^?1 in primary and 0.60 (0.042–4.7) mg kg^?1 in secondary feathers, and we found a poor effect of feather type on intra-individual Hg levels. We also found a negative effect of wing feather mass on Hg concentration but not of feather length and of its position in the wing. We hypothesize that differences in feather growth rate may be the main driver of between-feather differences in Hg concentrations, which can have implications in the interpretation of Hg concentrations in feathers. Finally, we recommend that, whenever possible, several feathers from the same individual should be analysed. The five innermost primaries have lowest mean deviations to both between-feather and intra-individual mean Hg concentration and thus should be selected under restrictive sampling scenarios.     

Adsorption Behavior of Crystal Violet and Congo Red Dyes on Heat-Treated Brazilian Palygorskite: Kinetic,Isothermal and Thermodynamic Studies

The effect of heat treatment on the adsorptive capacity of a Brazilian palygorskite to remove the dyes crystal violet (CV) and congo red (CR) was investigated. The natural palygorskite was calcined at different temperatures (300, 500 and 700 °C) for 4 h. Changes in the palygorskite structure were evaluated using X-ray diffraction, X-ray fluorescence, thermogravimetric and differential thermal analysis, N₂ adsorption/desorption and Fourier transform infrared spectroscopy. The adsorption efficiency of CV and CR was investigated through the effect of initial concentration, contact time, temperature, pH and dosage of adsorbent. The calcination increased the adsorption capacity of palygorskite, and the greatest adsorption capacity of CV and CR dyes occurred in the sample calcined at 700 °C (Pal-700T). The natural and calcined samples at 300 and 500 °C followed the Freundlich isothermal model, while the Pal-700T followed the Langmuir isothermal model. Adsorption kinetics results were well described by the Elovich model. Pal-700T showed better adsorption performance at basic pH, with removal greater than 98%, for both dyes. Pal-700T proved to be a great candidate for removing cationic and anionic dyes present in water.     

Vertical one-and-a-half syndrome in a patient with pecheron artery ischemia: A case report

Vertical one-and-a-half syndrome (VOHS) is an uncommon presentation resulting from a unilateral thalamomesencephalic stroke with involvement of the rostral interstitial nucleus of the medial longitudinal fasciculus and posterior commissure. The artery of Percheron (aPe) is a branch of the posterior cerebral artery (PCA) and it is a variant that arises as a solitary trunk supplying both medial thalami and upper midbrain. A 78-year-old female patient, presented at the hospital emergency with approximately 12 hours of sudden onset of diplopia, associated with dizziness. Neurological exam revealed torsional nystagmus associated with bilateral upgaze palsy with limitation of infraduction on the left. We describe a rare case of VOHS associated with ischemic alterations at the MRI suggesting an aPe impairment. The conjugate gaze control lies anatomically at the midbrain at the central nervous system (CNS). This report describes a rare type of VOHS and brings a new insight on a possible aPe topography possibly causing this clinical presentation.     

Coexistence of two chronic neuropathies in a young child: Charcot–marie–tooth disease type 1A and chronic inflammatory demyelinating polyneuropathy

We report an 18‐month‐old Charcot–Marie–Tooth type 1A (CMT1A) patient who developed a rapid‐onset neuropathy, with proximal and distal weakness, and non‐uniform nerve conduction studies. The neuropathy responded well to immunomodulation, confirming the coexistence of an inherited and an inflammatory neuropathy. Unexpected clinical and/or electrophysiological manifestations in CMT1A patients should alert clinicians to concomitant inflammatory neuropathy. In addition, this association raises reflections about disease mechanism in CMT1A. Muscle Nerve, 2010