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Arbutus unedo L. is a species with great economic impact in rural areas, and its fruits have several food applications and beneficial properties on human health. However, the fruits are highly perishable, and little is known about their characteristics. The present work thus aimed to evaluate the physicochemical and microbiological parameters of Arbutus unedo L. during two consecutive years from four different samples. Microbiological analysis was conducted at different times of preservation (days 0, 4, 11, and 21) and temperatures (room temperature, refrigeration, and freezing). Six fungal strains as representatives of the most prevalent mycobiota in fruits were used for molecular identification. The fruits had aw values of 0.916 ± 0.01 to 0.930 ± 0.01, pH values of 3.81 ± 0.01 to 3.82 ± 0.01, and °Brix values of 25.02 ± 0.49 to 28.52 ± 1.02. Microbiological analysis revealed that the predominant microbiota in fresh fruits were psychrotrophs (4.07 ± 0.25 log CFU/g), yeasts (3.39 ± 0.18 log CFU/g), mesophiles (3.26 ± 1.20 log CFU/g), and moulds (2.70 ± 0.55 log CFU/g). After a preservation period of 11 days, the microbial loads increased from 66 to 116% at 25 ± 1°C; while at 6.5 ± 1°C, the increase varied from 3 to 53%; except for moulds, for which a decrease was observed. The application of freezing temperature (21 days) showed a small increase for psychrotrophs and yeasts of 1.5 and 2.9%, respectively. The most prevalent moulds identified belonged to Rhizopus stolonifer var. stolonifer, Aspergillus carbonarius, and Penicillium brevicompactum, while yeasts belonged to Aureobasidium sp. and Saccothecium rubi. [ABSTRACT FROM AUTHOR]

The cheese rind is the natural food packaging of cheese and is subject to a wide range of external factors that compromise the appearance of the cheese, including color defects caused by spoilage microorganisms. First, eight films based on whey protein isolate (WPI) coatings were studied, of which IS3CA (WPI 5% + sorbitol 3% + citric acid 3%) was selected for presenting better properties. From the IS3CA film, novel films containing melanin M1 (74 µg/mL) and M2 (500 µg/mL) were developed and applied to cheese under proof-of-concept and industrial conditions. After 40 days of maturation, M2 presented the lowest microorganism count for all the microbial parameters analyzed. The cheese with M2 showed the lowest lightness, which indicates that it is the darkest cheese due to the melanin concentration. It was found that the mechanical and colorimetric properties are the ones that contribute the most to the distinction of the M2 film in cheese from the others. Using FTIR-ATR, it was possible to distinguish the rinds of M2 cheeses because they contained the highest concentrations of melanin. Thus, this study shows that the film with M2 showed the best mechanical, chemical and antimicrobial properties for application in cheese.

Secure computation is a powerful cryptographic tool that encompasses the evaluation of any multivariate function with arbitrary inputs from mutually distrusting parties. The oblivious transfer primitive serves is a basic building block for the general task of secure multi-party computation. Therefore, analyzing the security in the universal composability framework becomes mandatory when dealing with multi-party computation protocols composed of oblivious transfer subroutines. Furthermore, since the required number of oblivious transfer instances scales with the size of the circuits, oblivious transfer remains as a bottleneck for large-scale multi-party computation implementations. Techniques that allow one to extend a small number of oblivious transfers into a larger one in an efficient way make use of the oblivious transfer variant called randomized oblivious transfer. In this work, we present randomized versions of two known oblivious transfer protocols, one quantum and another post-quantum with ring learning with an error assumption. We then prove their security in the quantum universal composability framework, in a common reference string model.

Cervical spinal cord trauma represents more than half of the spinal cord injury (SCI) cases worldwide. Respiratory compromise, as well as severe limb motor deficits, are among the main consequences of cervical lesions. In the present work, a Gellan Gum (GG)-based hydrogel modified with GRGDS peptide, together with adipose tissue-derived stem/stromal cells (ASCs) and olfactory ensheathing cells (OECs), was used as a therapeutic strategy after a C2 hemisection SCI in rats. Hydrogel or cells alone, and a group without treatment, were also tested. Four weeks after injury, compound muscle action potentials (CMAPs) were performed to assess functional phrenic motor neuron (PhMN) innervation of the diaphragm; no differences were observed amongst groups, confirming that the PhMN pool located between C3 and C5 was not affected by the C2 injury or by the treatments. In the same line, the vast majority of diaphragmatic neuromuscular junctions remained intact. Five weeks post-injury, inspiratory bursting of the affected ipsilateral hemidiaphragm was evaluated through EMG recordings of dorsal, medial and ventral subregions of the muscle. All treatments significantly increased EMG amplitude at the ventral portion in comparison to untreated animals, but only the combinatorial group presented increased EMG amplitude at the medial portion of the hemidiaphragm. No differences were observed in forelimb motor function, neither in markers for axonal regrowth (neuronal tracers), astrogliosis (GFAP) and inflammatory cells (CD68). Moreover, using Von Frey testing of mechanical allodynia, it was possible to find a significant effect of the group combining hydrogel and cells on hypersensitivity; rats with a SCI displayed an increased response of the contralateral forelimb to a normally innocuous mechanical stimulus, but after treatment with the combinatorial therapy this behavior was reverted almost to the levels of uninjured controls. These results suggest that our therapeutic approach may have beneficial effects on both diaphragmatic recovery and sensory function., (Copyright © 2020 Gomes, Ghosh, Lima, Goulão, Moreira-Gomes, Martins-Macedo, Urban, Wright, Gimble, Sousa, Silva, Lepore and Salgado.)

Compromise in inspiratory breathing following cervical spinal cord injury (SCI) is caused by damage to descending bulbospinal axons originating in the rostral ventral respiratory group (rVRG) and consequent denervation and silencing of phrenic motor neurons (PhMNs) that directly control diaphragm activation. In a rat model of high-cervical hemisection SCI, we performed systemic administration of an antagonist peptide directed against phosphatase and tensin homolog (PTEN), a central inhibitor of neuron-intrinsic axon growth potential. PTEN antagonist peptide (PAP4) robustly restored diaphragm function, as determined with electromyography (EMG) recordings in living SCI animals. PAP4 promoted substantial, long-distance regeneration of injured rVRG axons through the lesion and back toward PhMNs located throughout the C3-C5 spinal cord. These regrowing rVRG axons also formed putative excitatory synaptic connections with PhMNs, demonstrating reconnection of rVRG-PhMN-diaphragm circuitry. Lastly, re-lesion through the hemisection site completely ablated functional recovery induced by PAP4. Collectively, our findings demonstrate that axon regeneration in response to systemic PAP4 administration promoted recovery of diaphragmatic respiratory function after cervical SCI., (Copyright © 2019 Urban et al.)

Dysfunction of the fast-inactivating Kv3.4 potassium current in dorsal root ganglion (DRG) neurons contributes to the hyperexcitability associated with persistent pain induced by spinal cord injury (SCI). However, the underlying mechanism is not known. In light of our previous work demonstrating modulation of the Kv3.4 channel by phosphorylation, we investigated the role of the phosphatase calcineurin (CaN) using electrophysiological, molecular, and imaging approaches in adult female Sprague Dawley rats. Pharmacological inhibition of CaN in small-diameter DRG neurons slowed repolarization of the somatic action potential (AP) and attenuated the Kv3.4 current. Attenuated Kv3.4 currents also exhibited slowed inactivation. We observed similar effects on the recombinant Kv3.4 channel heterologously expressed in Chinese hamster ovary cells, supporting our findings in DRG neurons. Elucidating the molecular basis of these effects, mutation of four previously characterized serines within the Kv3.4 N-terminal inactivation domain eliminated the effects of CaN inhibition on the Kv3.4 current. SCI similarly induced concurrent Kv3.4 current attenuation and slowing of inactivation. Although there was little change in CaN expression and localization after injury, SCI induced upregulation of the native regulator of CaN 1 (RCAN1) in the DRG at the transcript and protein levels. Consistent with CaN inhibition resulting from RCAN1 upregulation, overexpression of RCAN1 in naive DRG neurons recapitulated the effects of pharmacological CaN inhibition on the Kv3.4 current and the AP. Overall, these results demonstrate a novel regulatory pathway that links CaN, RCAN1, and Kv3.4 in DRG neurons. Dysregulation of this pathway might underlie a peripheral mechanism of pain sensitization induced by SCI. SIGNIFICANCE STATEMENT Pain sensitization associated with spinal cord injury (SCI) involves poorly understood maladaptive modulation of neuronal excitability. Although central mechanisms have received significant attention, recent studies have identified peripheral nerve hyperexcitability as a driver of persistent pain signaling after SCI. However, the ion channels and signaling molecules responsible for this change in primary sensory neuron excitability are still not well defined. To address this problem, this study used complementary electrophysiological and molecular methods to determine how Kv3.4, a voltage-gated K + channel robustly expressed in dorsal root ganglion neurons, becomes dysfunctional upon calcineurin (CaN) inhibition. The results strongly suggest that CaN inhibition underlies SCI-induced dysfunction of Kv3.4 and the associated excitability changes through upregulation of the native regulator of CaN 1 (RCAN1)., (Copyright © 2017 the authors 0270-6474/17/378257-17$15.00/0.)

Introduction: Experiences of clinical and nonclinical learning environments, as well as assessment and study environments influence student satisfaction with their medical schools. Student-tutor ratios may impact on their perception of clinical learning environments. The aim of this study was to analyze medical students' satisfaction and student-tutor ratios in relation to medical schools' number of admissions., Materials and Methods: A questionnaire was created, regarding learning, assessment and study environments in eight medical schools. 2037 students participated in this cross-sectional study. Cronbach' alpha (internal consistency) was calculated and principal component analysis was conducted. Pearson correlations and multiple comparisons were analyzed., Results: Assessment environments showed the highest satisfaction scores and clinical learning environments the lowest scores. The national student-tutor ratio in clinical rotations is 7.53; there are significant differences among schools. Institutions with higher number of admissions showed the lowest scores of overall student satisfaction (r = -0.756; p < 0.05), which decreased with progression in the medical course. High student-tutor ratios are strongly correlated with low levels of satisfaction regarding clinical learning environments (r = -0.826; p < 0.05)., Discussion: Clinical learning environments show the lowest satisfaction scores, which may expose the effect of high ratios in clinical rotations. Depending on the number of admissions, significant differences between medical schools were found. Quality of teaching-learning strategies and articulation with hospitals might also be important variables., Conclusion: Medical schools with more admissions might be more susceptible to lower scores of student satisfaction. High student-tutor ratios in clinical rotations may reduce the quality of learning experiences and inhibit the acquisition of competences.