Improvement in Solubility-Permeability Interplay of Psoralens from Brosimum gaudichaudii Plant Extract upon Complexation with Hydroxypropyl-ß-cyclodextrin.

Psoralen (PSO) and 5-methoxypsoralen (5-MOP) are widely used drugs in oral photochemotherapy against vitiligo and major bioactive components of root bark extract of Brosimum gaudichaudii Trécul (EBGT), previously standardized by LC-MS. However, the exceptionally low water solubility of these psoralens can cause incomplete and variable bioavailability limiting their applications and patient adherence to treatment. Therefore, the purpose of this work was to investigate the effects of 2-hydroxypropyl-ß-cyclodextrin (HP-ß-CD) inclusion complex on the solubility and jejunal permeability of PSO and 5-MOP from EBGT. Characterization of inclusion complexes were evaluated by current methods in nuclear magnetic resonance studies on aqueous solution, Fourier transform infrared spectroscopy, thermal analysis, and scanning electron microscopy in solid state. Ex vivo rat jejunal permeability was also investigated and compared for both pure psoralens and plant extract formulation over a wide HP-ß-CD concentration range (2.5 to 70 mM). Phase solubility studies of the PSO- and 5-MOP-HP-ß-CD inclusion complex showed 1:1 inclusion complex formation with small stability constants (Kc < 500 M−1). PSO and 5-MOP permeability rate decreased after adding HP-ß-CD by 6- and 4-fold for pure standards and EBGT markers, respectively. Nevertheless, the complexation with HP-ß-CD significantly improved solubility of PSO (until 10-fold) and 5-MOP (until 31-fold). As a result, the permeability drop could be overcome by solubility augmentation, implying that the HP-ß-CD inclusion complexes with PSO, 5-MOP, or EBGT can be a valuable tool for designing and developing novel oral drug product formulation containing these psoralens for the treatment of vitiligo.

Aerobic exercise with blood flow restriction: Energy expenditure, excess postexercise oxygen consumption, and respiratory exchange ratio.

We compared the effects of aerobic exercise with and without blood flow restriction (BFR) to high-intensity aerobic exercise on energy expenditure (EE), excess Postexercise oxygen consumption (EPOC), and respiratory exchange ratio (RER) during and after exercise. Twenty-two recreationally active males randomly completed the following experimental conditions: AE-aerobic exercise without BFR, AE + BFR-aerobic exercise with BFR, HIAE-high-intensity aerobic exercise, CON-non-exercise control condition. EE was significantly (p < 0.05) greater during exercise for HIAE compared to all conditions, and for AE + BFR compared to AE and CON during and postexercise exercise. There were no significant (p > 0.05) differences in EPOC between HIAE and AE + BFR at any time point, however, both conditions were significantly (p < 0.05) greater than the AE (d = 1.50 and d = 1.03, respectively) and CON at the first 10 min postexercise. RER during exercise for HIAE was significantly (p < 0.05) greater than AE + BFR at the first 6 min of exercise (p = 0.003, d = 0.88), however, no significant differences were observed from 9 min up to the end of the exercise. HIAE was also significantly (p < 0.05) greater than AE and CON at all time points during exercise, whereas, AE + BFR was significantly (p < 0.05) greater than CON at all time points but not significantly (p < 0.05) different than AE (p < 0.05); although the overall session RER was significantly (p < 0.05) greater during AE + BFR than AE. Altogether, continuous AE + BFR results in greater EE compared to volume matched AE, as well as a similar EPOC compared to HIAE.

Physiological and Perceptual Responses to Aerobic Exercise With and Without Blood Flow Restriction.

ABSTRACT: Silva, JCG, Domingos-Gomes, JR, Freitas, EDS, Neto, GR, Aniceto, RR, Bemben, MG, Lima-dos-Santos, A, and Cirilo-Sousa, MS. Physiological and perceptual responses to aerobic exercise with and without blood flow restriction. J Strength Cond Res 35(9): 2479-2485, 2021-Although previous studies have demonstrated the potential benefits of aerobic exercise (AE) with blood flow restriction (BFR), these findings have been limited by the approaches used to determine the occlusive pressure. In addition, the physiological and perceptual responses of AE with BFR compared to high-intensity interval exercise (HIIE) remain unclear. Thus, we investigated the physiological and perceptual responses to AE with and without BFR, and HIIE. Twenty-two men were randomly assigned to 4 experimental conditions: AE (40% of maximal oxygen consumption [V˙o2peak]), AE with 50% of BFR (AE-BFR: 40% VV˙o2peak), HIIE (80% V˙o2peak), and a no exercise control condition (CON: 50% of BFR). Each exercise bout lasted 18 minutes, during which oxygen consumption (V˙o2), heart rate (HR), and ratings of perceived exertion (RPE) were measured at rest and at every 3 minutes during exercise. Ratings of discomfort before and after each trial. The HIIE condition induced the greatest increases in V˙o2 and HR (p < 0.05), whereas AE-BFR was significantly (p < 0.05) greater than AE and CON. HIIE and AE-BFR also elicited the greatest (p < 0.05), but similar (p > 0.05), increases in RPE during exercise, although AE-BFR was significantly greater than HIIE immediately after exercise (p < 0.05). AE-BFR and HIIE also induced similar levels of discomfort after exercise (p > 0.05). In conclusion, HIIE induced the greatest increases in V˙o2 and HR, although the perceptual responses were essentially the same compared with AE-BFR. However, albeit inferior to HIIE, V˙o2 was greater during AE-BFR compared with AE, indicating that this training method may be used to replace HIIE and still significantly elevate V˙o2.

Comparative study of micronucleus assays and dicentric plus ring chromosomes for dose assessment in particular cases of partial-body exposure.

Purpose: The goal was to compare the micronucleus (MN) and dicentric plus ring chromosomes (D + R) assays for dose assessment in cases of partial body irradiations (PBI). Materials and methods: We constructed calibration curves for each assay at doses ranging from 0 to 5 Gy of X-rays at dose rate of 0.275 Gy/min. To simulate partial-body exposures, blood samples from two donors were irradiated with 0.5, 1, 2 and 4 Gy and the ratios of irradiated to unirradiated blood were 25, 50, and 100%. Different tests were used to confirm if all samples were overdispersed or zero-inflated and for partial-body dose assessment we used the Qdr, Dolphin and Bayesian model. Results: In our samples for D + R calibration curve, practically all doses agreed with Poisson assumption, but MN exhibited overdispersed and zero-inflated cellular distributions. The exact Poisson tests and zero-inflated tests demonstrate that virtually all samples of D + R from PBI simulation fit the Poisson distribution and were not zero-inflated, but the MN samples were also overdispersed and zero-inflated. In the partial-body estimation, when Qdr and Dolphin methods were used the D + R results were better than MN, but the doses estimation defined by the Bayesian methodology were more accurate than the classical methods. Conclusions: Dicentric chromosomes continue to prove to be the best biological marker for dose assessment. However exposure scenarios of partial-body estimation, overdispersion and zero-inflation may not occur, it being a critical point not only for dose assessment, but also to confirm partial-body exposure. MN could be used as alternative assay for partial-body dose estimation, but in case of an accident without any information, the MN assay could not define whether the accident was a whole-body irradiation (WBI) or a PBI.

Are there differences in auscultatory pulse in total blood flow restriction between positions, limbs and body segments? / Existem diferenças no pulso auscultatório da restrição total de fluxo sanguíneo entre as posições, membros e segmentos corporais?

Verification of the auscultatory pulse in total blood flow restriction (BFR) has been a limiting factor in studies due to the way in which it is evaluated and prescribed, as hemodynamic measurements can be directly affected by gravity. The aim of the present study was to compare the auscultatory pulse in BFR between positions, genders, limbs and body segments in healthy young individuals. A total of 156 subjects participated in the study, 76 of whom were male and 80 of whom were female (23.9±3.7 years, 66.5±11.5 kg, 1.67±0.07 m). After filling in registration data, anthropometry was evaluated, and BFR pressure was determined. BFR was evaluated in a randomized manner in both limbs (upper and lower) and in both segments (right and left) in the following positions: a) lying in the supine position; B) sitting with knees and trunk at 90°; and c) standing in the anatomical position. Significant differences were observed between the lying, sitting and standing positions (p<0.05), between genders (p<0.05), between limbs (p<0.05) and between the right and left segments in the lower limb in both genders [males (p=0.014) and females (p=0.009)] in the lying position. However, no significant differences were observed between the right and left segments in the upper limbs (p>0.05). The BFR point appears to differ between positions, genders, lower limbs and segments. Therefore, it is recommended that health professionals should check the BFR point in the position relating to the exercise that will be performed, taking into account gender, lower limbs and body segments.

A verificação do pulso auscultatório da restrição de fluxo sanguíneo (RFS) total tem sido fator limitante dos estudos devido à forma de avaliação e prescrição, já que as medidas hemodinâmicas podem sofrer influência direta da gravidade. O objetivo do presente estudo foi comparar o pulso auscultatório da RFS entre as posições, sexo, membros e segmentos corporais em jovens saudáveis. Participaram do estudo 156 sujeitos, sendo 76 homens e 80 mulheres (23,9±3,7 anos, 66,5±11,5 kg, 1,67±0,07 m). Após o preenchimento da ficha cadastral, foram avaliadas a antropometria e em seguida houve a determinação da pressão de RFS. A RFS foi avaliada de forma randomizada em ambos os membros (superiores e inferiores) e ambos os segmentos (direito e esquerdo) nas posições: a) deitada em decúbito dorsal; b) sentada com joelhos e tronco em 90°; e c) em pé na posição anatômica. Observaram-se diferenças significativas entre as posições deitado, sentado e em pé (p<0,05), entre os sexos (p<0,05), entre os membros (p<0,05) e entre os segmentos direito vs. esquerdo no membro inferior em ambos os sexos [homem (p=0,014) e mulher (p=0,009)] na posição deitada. Entretanto, observou-se não existir diferenças significativas entre os segmentos direito vs. esquerdo no membro superior (p>0,05). O ponto da RFS parece diferir entre as posições, sexo, membros inferiores e segmentos. Portanto, recomenda-se que os profissionais da área da saúde devam verificar o ponto da RFS na posição referente ao exercício que será realizado, levando em consideração o sexo, membros inferiores e segmentos corporais.

Mood Effects of Blood Flow Restriction Resistance Exercise Among Basketball Players.

This study compared the acute effects of resistance exercise with and without blood flow restriction (BFR) on basketball players' mood states. A total of 11 male basketball players (M age = 19.9, SD = 2.8 years; M height = 180.8, SD = 7.8 cm; M weight = 71.1, SD = 9.1 kg; M body mass index = 22.1, SD = 1.9 kg/m2) were randomly assigned to two experimental conditions: (a) low-load resistance exercise with BFR (LLRE + BFR) and high-load resistance exercise (HLRE) without BFR. We measured mood state with the Brunel Mood Scale before and after each session. There was a significant interaction effect such that there was increased fatigue over time with LLRE + BFR ( p = .001, Δ% = 169.2). Regarding total mood disorder, there were significant pre and postexercise differences between athletes exposed to both the LLRE + BFR and HLRE conditions ( p = .048) and a decharacterization of the iceberg mood profile in the post-training LLRE + BFR condition. LLRE + BFR, compared to HLRE, promoted an acute negative effect on mood state, decharacterization of the iceberg profile, total mood disturbance, and increased participant fatigue, suggesting that this method of strength training should be avoided before sports competitions.

The effects of water-based exercise in combination with blood flow restriction on strength and functional capacity in post-menopausal women.

Water-based exercise and low-intensity exercise in combination with blood flow restriction (BFR) are two methods that have independently been shown to improve muscle strength in those of advancing age. The objective of this study was to assess the long-term effect of water-based exercise in combination with BFR on maximum dynamic strength and functional capacity in post-menopausal women. Twenty-eight women underwent an 8-week water-based exercise program. The participants were randomly allocated to one of the three groups: (a) water exercise only, (b) water exercise + BFR, or (c) a non-exercise control group. Functional capacity (chair stand test, timed up and go test, gait speed, and dynamic balance) and strength testing were tested before and after the 8-week aquatic exercise program. The main findings were as follows: (1) water-based exercise in combination with BFR significantly increased the lower limb maximum strength which was not observed with water-based exercise alone and (2) water-based exercise, regardless of the application of BFR, increased functional performance measured by the timed up and go test over a control group. Although we used a healthy population in the current study, these findings may have important implications for those who may be contraindicated to using traditional resistance exercise. Future research should explore this promising modality in these clinical populations.

The acute effect of resistance exercise with blood flow restriction with hemodynamic variables on hypertensive subjects.

The purpose of this study was to analyze systolic blood pressure (SBP), diastolic blood pressure (DBP) and the heart rate (HR) before, during and after training at moderate intensity (MI, 50%-1RM) and at low intensity with blood flow restriction (LIBFR). In a randomized controlled trial study, 14 subjects (average age 45±9,9 years) performed one of the exercise protocols during two separate visits to the laboratory. SBP, DBP and HR measurements were collected prior to the start of the set and 15, 30, 45 and 60 minutes after knee extension exercises. Repeated measures of analysis of variance (ANOVA) were used to identify significant variables (2 × 5; group × time). The results demonstrated a significant reduction in SBP in the LIBFR group. These results provide evidence that strength training performed acutely alters hemodynamic variables. However, training with blood flow restriction is more efficient in reducing blood pressure in hypertensive individuals than training with moderate intensity.