Dietary Nitrate Supplementation Is Not Helpful for Endurance Performance at Simulated Altitude Even When Combined With Intermittent Normobaric Hypoxic Training.

Introduction: Training intensity and nutrition may influence adaptations to training performed in hypoxia and consequently performance outcomes at altitude. This study investigates if performance at simulated altitude is improved to a larger extent when high-intensity interval training is performed in normobaric hypoxia and if this is potentiated when combined with chronic dietary nitrate (NO3 -) supplementation. Methods: Thirty endurance-trained male participants were allocated to one of three groups: hypoxia (13% FiO2) + NO3 -; hypoxia + placebo; and normoxia (20.9% FiO2) + placebo. All performed 12 cycling sessions (eight sessions of 2*6 × 1 min at severe intensity with 1 min recovery and four sessions of 4*6*10 s all-out with 20 s recovery) during a 4-week period (three sessions/week) with supplementation administered 3-2.5 h before each session. An incremental exhaustion test, a severe intensity exercise bout to exhaustion (T lim) and a 3 min all-out test (3AOT) in hypoxia (FiO2 = 13%) with pulmonary oxygen uptake ( V ˙ O2), V ˙ O2 kinetics, and changes in vastus lateralis local O2 saturation (SmO2) measured were completed by each participant before and after training. Results: In all tests, performance improved to the same extent in hypoxia and normoxia, except for SmO2 after T lim (p = 0.04, d = 0.82) and 3AOT (p = 0.03, d = 1.43) which were lower in the two hypoxic groups compared with the normoxic one. Dietary NO3 - supplementation did not bring any additional benefits. Conclusion: Performance at simulated altitude was not improved to a larger extent when high-intensity interval training was undertaken in normobaric hypoxic conditions, when compared with normoxic training. Additionally, dietary NO3 - supplementation was ineffective in further enhancing endurance performance at simulated altitude.

Perivascular clusters of Th2 cells and M2 macrophages in allergic contact dermatitis to methylchloroisothiazolinone and methylisothiazolinone.

BACKGROUND: Methylisothiazolinone (MI) and Methylchloroisothiazolinone (MCI) are among the most common skin sensitizers, yet the immunological events that occur during MCI/MI allergic contact dermatitis (ACD) are still poorly understood. OBJECTIVES: To analyse dendrocytes, macrophage subtypes and T cells in skin during the elicitation phase of MCI/MI ACD. METHODS: Thirteen patients with positive patch test reactions to MCI/MI (ACD group) and 11 individuals with negative patch test results were selected. Skin biopsies were only performed at 48 hours of patch testing. Immunohistochemistry was conducted to assess T cells, dendrocytes (Factor XIIIa), M1 (p-Stat1, CD68) and M2 (c-Maf, CD163) macrophages. Transcriptional analyses were performed for cytokines and related factors, and further compared to atopic dermatitis samples (n=4). Immunofluorescence assays addressed T cells location, along with IL-4 or IL-13, within the skin. RESULTS: MCI/MI elicited dermal dendrocytes and macrophages, pronouncedly the M2 subtype. T cells, majorly CD4+ T cells, accumulated in the perivascular areas. Similarly, abundant IL-4 protein was detected in these areas. There was an upregulation of IL-4 and IL-13 mRNA expression, a mild increase in IFNG mRNA levels and a down-regulation of RORC in the ACD group. Immunofluorescence revealed dermal clusters of T cells co-localized with IL-4. CONCLUSIONS: M2 macrophages and Th2 cells participate in the immunopathogenesis of MCI/MI ACD. Dermal dendrocytes and M2 macrophages may assist the formation of CD4+ T cells perivascular clusters. These findings render a mechanistic insight into the MCI/MI reaction. Further analysis at different timepoints of patch testing is required to fully comprehend this ACD kinetics.

Comparison between traditional strength training and complex contrast training on soccer players.

BACKGROUND: The purpose of this study was to compare traditional strength training (TST) versus complex and contrast training (CCT) on sprint, change of direction speed (COD) and squat jump (SJ) in young male soccer players. METHODS: Twenty-two soccer players (age: 18.4±0.4 years, body mass: 70.2±9.1 kg, height: 179.9±7.5 cm), were randomly assigned to one of two groups: TST (N.=12) and CCT (N.=10). The study was conducted using a randomized experimental design over an eight-week period. The participants assigned to the CCT group performed high-power exercises paired with high-velocity exercises. The participants assigned to the TST group performed resistance exercises in a straight-set forma. During the study period, sprint tests for 5, 10, 20 and 30 m split times, COD and SJ were applied. A two-way ANOVA was applied, and the alpha level was P<0.05. RESULTS: The results demonstrated that the CCT regimen elicited significant within-group differences in 5 m sprint time (1.032 s to 0.997 s, pre- and postintervention, respectively, effect size (ES) = -0.5, medium; P=0.04), COD (5.963 s to 5.639 s, pre- and postintervention, respectively, ES -2.7, large; P<0.001) and SJ (30.9 cm to 34.4 cm, pre- and postintervention, respectively, ES =0.8, large; P<0.001). Conversely, the TST did not elicit significant within-group differences for any of the dependent variables. No differences were found between groups at the post-test time point. CONCLUSIONS: In conclusion, the CCT protocol could be used to improve sprint, COD and SJ in male soccer players.

Effects of musical cadence in the acute physiologic adaptations to head-out aquatic exercises.

The purpose of this study was to analyze the relationships between musical cadence and the physiologic adaptations to basic head-out aquatic exercises. Fifteen young and clinically healthy women performed, immersed to the breast, a cardiovascular aquatic exercise called the "rocking horse." The study design included an intermittent and progressive protocol starting at a 90 b.min(-1) rhythm and increasing every 6 minutes, by 15 b.min(-1), up to 195 b.min(-1) or exhaustion. The rating of perceived effort (RPE) at the maximal heart rate achieved during each bout (HRmax), the percentage of the maximal theoretical heart rate estimated (%HRmax), and the blood lactate concentration ([La-]) were evaluated. The musical cadence was also calculated at 4 mmol.L(-1) of blood lactate (R4), the RPE at R4 (RPE@R4), the HR at R4 (HR@R4), and the %HRmax at R4 (%HRmax@R4). Strong relationships were verified between the musical cadence and the RPE (R2 = 0.85; p < 0.01), the HRmax (R2 = 0.66; p < 0.01), the %HRmax (R = 0.61; p < 0.01), and the [La-] (R2 = 0.54; p < 0.01). The R4 was 148.13 +/- 17.53 b.min, the RPE@R4 was 14.53 +/- 2.53, the HR@R4 was 169.33 +/- 12.06 b.min, and the %HRmax@R4 was 85.53 +/- 5.72%. The main conclusion is that increasing musical cadence created an increase in the physiologic response. Therefore, instructors must choose musical cadences according to the goals of the session they are conducting to achieve the desired intensity.

Two Brazilian cases of IgA pemphigus.

IgA pemphigus is a rare, neutrophilic, acantholytic skin disorder with approximately 70 cases described in the literature. We report two patients with the subcorneal pustular dermatosis (SPD) type of IgA pemphigus. Initially, both patients were misdiagnosed as subcorneal pustular dermatosis of Sneddon and Wilkinson. The correct diagnosis was only made after detecting intercellular IgA depositions in the epidermis by direct immunofluorescence. Immunoblotting (IB) of normal human epidermal extracts, performed on both sera, was negative for Dsg 1, Dsg 3, BP 230, BP 180, 210 kDa envoplakin, and 190 kDa periplakin. ELISA for desmogleins (Dsg 1 and Dsg 3) showed that neither of the cases had IgA antibodies to Dsg. The c-DNA transfection test for desmocollins (Dsc) revealed that the IgA antibodies of both patients reacted with desmocollin 1. This result supports the hypothesis that the autoantigen in SPD type IgA pemphigus is desmocollin 1.

Fenômeno de Lúcio (eritema necrosante) na gestação: relato de caso e revisão de literatura / Lucio's phenomenon (erythema necrotisans) in pregnancy: a case report and an overview

A gravidez associa-se a maior freqüência dos estados reacionais relacionados à hanseníase. Um desses estudos, denominado fenômeno de Lúcio ou eritema necrosante, é observado entre os portadores de hanseníase avançada sem tratamento e acomete, no Brasil, doentes com a forma virchowiana ou com formas próximas deste pólo. Relata-se o caso de uma gestante de 25 anos, sem diagnóstico prévio de hanseníases, que apresentava áreas extensas de necrose cutânea seca, com contornos irregulares, acometendo face, tronco, membros superiores e inferiores, bem como lesões eritêmato-violáceas com bordas irregulares na face, madarose e rarefação ciliar; não havendo evidências de comprometimento sistêmico nem fetal no momento da admissão. Recebeu poliquimioterapia para hanseníase associada a corticosteróides e a antibióticos, e foi submetida a debridamento cirúrgico das lesões necróticas. Vinha-se mantendo estável até a ocorrência de insuficiência respiratória aguda, seguida por parto prematuro de feto morto e óbito

Superantígenos em dermatologia / Superantigens in dermatology

Os superantígenos säo moléculas de origem microbiana, bacteriana (toxinas) ou viral, que, por meio do complexo maior de histocompatibilidade, estimulam as células T por ligaçäo direta aos receptores de células T (porçäo v-beta). Diferem dos demais antígenos por sua intensa seletividade e capacidade de estimular linfócitos T mediante mecanismos independentes do processamento antigênico intracelular por células apresentadoras de antígenos. Têm sido apontados como fatores de importância na etiopatogenia de enfermidades dematológicas, principalmente as toxinas bacterianas (Staphylococcus e Streptococcus). Os superantígenos podem levar à liberaçäo massiva de linfocinas e chegam a ativar até cerca de 30 porcento dos linfócitos periféricos. Acredita-se que os superantígenos possam exercer papel importante na induçäo e exacerbaçäo das doenças inflamatórias.