Different molecules have been tested as analog receptors due to their capacity to bind bacteria and prevent cell adhesion. By using in vitro assays, the present study characterized the aqueous and ...alkaline extracts from microalgae Pavlova lutheri and Pavlova gyrans and evaluated the capacity of these extracts to adhere to enterobacteria (Salmonella Typhimurium). The aqueous and alkaline extracts of both species were fractionated via freeze-thawing, giving rise to soluble and insoluble (precipitate) fractions in cold water. The obtained fractions were studied using thermogravimetric, methylation analyses, and using 1D and 2D NMR techniques. The cold-water-soluble fractions obtained from the aqueous extracts were mainly composed of highly branched (1→3),(1→6)-β-glucans, whereas the cold-water-precipitate fractions were constituted by (1→3)-β-glucans. The alkaline extract fractions showed similar compositions with a high protein content, and the presence of glycosides (sulfoquinovosylglycerol (SQG), digalactosylglycerol (DGG)), and free fatty acids. The linear (1→3)-β-glucans and the alkaline extract fractions showed an adhesion capacity toward Salmonella. The chemical composition of the active fractions suggested that the presence of three-linked β-glucose units, as well as microalgal proteins and glycosides, could be important in the adhesion process. Therefore, these microalgal species possess a high potential to serve as a source of anti-adhesive compounds.
At the beginning of 2020 a respiratory diseased named COVID-19 rapidly spread worldwide. Due to the presence of comorbidities and a greater susceptibility to infections, older adults are the ...population most affected by this pandemic. An efficient pharmacological treatment for COVID-19 is not ready yet; in the meanwhile, a general quarantine has been initiated as a preventive action against the spread of the disease. If on one side this countermeasure is slowing the spread of the virus, on the other side is also reducing the amount of physical activity. Sedentariness is associated with numerous negative health outcomes and increase risk of fall, fractures and disabilities in older adults. Models of physical inactivity have been widely studied in the past decades, and most studies agreed that is necessary to implement physical exercise (such as walking, low load resistance or in bed exercise) during periods of disuse to protect muscle mass and function from catabolic crisis. Moreover, older adults have a blunted response to physical rehabilitation, and a combination of intense resistance training and nutrition are necessary to overcome the loss of in skeletal muscle due to disuse.
Lift weights to fight overweight Paoli, Antonio; Moro, Tatiana; Bianco, Antonino
Clinical physiology and functional imaging,
January 2015, Letnik:
35, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Summary
Although resistance training (RT) has long been accepted as a means for developing and maintaining muscular strength, endurance, power and muscle mass, its beneficial relationship with health ...factors and chronic disease has only recently been recognized in the scientific literature. Prior to 1990, resistance training was not a part of the recommended guidelines for exercise training and rehabilitation for either the American Heart Association or the American College of Sports Medicine (ACSM). In 1990, the ACSM recognized resistance training as a significant component of a comprehensive fitness programme for healthy adults of all ages, a position subsequently confirmed few years after. At present, even though interest in clinical applications of RT is increasing, there are still some concerns, among physicians, about the use of this exercise methodology in weight control programmes. This review aims to explore the metabolic effects of RT and its efficacy and feasibility in overweight subjects.
The force drop after transcranial magnetic stimulation (TMS) delivered to the motor cortex during voluntary muscle contractions could inform about muscle relaxation properties. Because of the ...physiological relation between skeletal muscle fiber-type distribution and size and muscle relaxation, TMS could be a noninvasive index of muscle relaxation in humans. By combining a noninvasive technique to record muscle relaxation in vivo (TMS) with the gold standard technique for muscle tissue sampling (muscle biopsy), we investigated the relation between TMS-induced muscle relaxation in unfatigued and fatigued states, and muscle fiber-type distribution and size. Sixteen participants (7F/9M) volunteered to participate. Maximal knee-extensor voluntary isometric contractions were performed with TMS before and after a 2-min sustained maximal voluntary isometric contraction. Vastus lateralis muscle tissue was obtained separately from the participants' dominant limb. Fiber type I distribution and relative cross-sectional area of fiber type I correlated with TMS-induced muscle relaxation at baseline (
= 0.67, adjusted
= 0.01;
= 0.74, adjusted
= 0.004, respectively) and normalized TMS-induced muscle relaxation as a percentage of baseline (
= 0.50, adjusted
= 0.049;
= 0.56, adjusted
= 0.031, respectively). The variance in the normalized peak relaxation rate at baseline (59.8%,
< 0.001) and in the fatigue resistance (23.0%,
= 0.035) were explained by the relative cross-sectional area of fiber type I to total fiber area. Fiber type I proportional area influences TMS-induced muscle relaxation, suggesting TMS as an alternative method to noninvasively inform about skeletal muscle relaxation properties.
Transcranial magnetic stimulation (TMS)-induced muscle relaxation reflects intrinsic muscle contractile properties by interrupting the drive from the central nervous system during voluntary muscle contractions. We showed that fiber type I proportional area influences the TMS-induced muscle relaxation, suggesting that TMS could be used for the noninvasive estimation of muscle relaxation in unfatigued and fatigued human muscles when the feasibility of more direct method to study relaxation properties (i.e., muscle biopsy) is restricted.
Amino Acid Sensing in Skeletal Muscle Moro, Tatiana; Ebert, Scott M; Adams, Christopher M ...
Trends in endocrinology and metabolism,
11/2016, Letnik:
27, Številka:
11
Journal Article
Recenzirano
Odprti dostop
Aging impairs skeletal muscle protein synthesis, leading to muscle weakness and atrophy. However, the underlying molecular mechanisms remain poorly understood. Here, we review evidence that ...mammalian/mechanistic target of rapamycin complex 1 (mTORC1)-mediated and activating transcription factor 4 (ATF4)-mediated amino acid (AA) sensing pathways, triggered by impaired AA delivery to aged skeletal muscle, may play important roles in skeletal muscle aging. Interventions that alleviate age-related impairments in muscle protein synthesis, strength, and/or muscle mass appear to do so by reversing age-related changes in skeletal muscle AA delivery, mTORC1 activity, and/or ATF4 activity. An improved understanding of the mechanisms and roles of AA sensing pathways in skeletal muscle may lead to evidence-based strategies to attenuate sarcopenia.
Purpose
Dragon Boat discipline has become a popular type of physical exercise among women with breast cancer. The present study aims to investigate the effects of Dragon Boat activity on body ...composition, physical function, and psychosocial aspects (i.e., body appreciation and quality of life QoL) in women operated for breast cancer.
Methods
Thirty-one women (age, 57.88 ± 7.88 years; BMI, 27.86 ± 6.38 kg·m
−2
) with a previous breast removal surgery were recruited and randomized into two groups: Dragon Boat group (DB,
N
= 18) or a home-based non-supervised training program (home exercise group; HG,
N
= 13). All participants underwent body composition, handgrip test, 30-s chair stand test (30CST), 6-min walking test (6MWT), and shoulder mobility measurements at baseline and after 12 weeks of intervention. Participants also filled out the Body Appreciation Scale-2 (BAS-2) and the Short Form Health Survey-12 (SF-12) self-report questionnaires.
Results
Dragon Boat activity significantly improved the 30CST (+ 6%,
p
= .011) and 6MWT performance (+ 30%,
p
= .011) compared to a home-based non-supervised training program. Moreover, 20% (3/15 women) of women in the DB group obtained a reliable change from pre- to post-intervention in the BAS-2 and in the mental QoL component of the SF-12 (
vs
15% and 0% of the HC group). No reliable change emerged for the physical component of the SF-12.
Conclusion
Dragon Boat activity is efficient to improve lower limb strength in women operated for breast cancer. Furthermore, Dragon Boat activity emerged to improve body appreciation and mental QoL in some of the women assigned to this activity. Importantly, no adverse events were documented during the intervention.
Trial registration
NCT05206526 (10/02/2022)
•Our outcomes indicated that intermittent fasting may produce improvements in body composition by decreasing body mass, body mass index, fat mass, and body fat percentage while preserving fat-free ...mass in adults performing resistance training.
This systematic review and meta-analysis evaluated the influence of intermittent fasting (IF) in combination with resistance training (RT) on body composition outcomes. Studies examining IF vs. non-IF diets in individuals performing RT, published up to February 2021, were identified through PubMed, the Cochrane Library, Web of Science, Embase, and SCOPUS databases. Eight studies, including 221 participants were analyzed using a random-effects model to calculate weighted mean differences (WMDs) with 95% confidence intervals (CIs). Results indicated that IF had a significant effect on body mass (WMD = -2.08 kg; 95% CI: -3.04, -1.13), fat mass (WMD = -1.36 kg; 95% CI: -1.94, -0.78), body mass index (WMD = -0.52 kg/m2; 95% CI: -0.85, -0.19), and body fat percentage (WMD = -1.49%; 95% CI: -2.24, -0.74) relative to non-IF diets, without a significant effect for fat-free mass (WMD = -0.27 kg; 95% CI: -0.82, 0.28). The present systematic review and meta-analysis demonstrates potentially beneficial effects of IF in combination with RT for reducing body mass and body fat relative to non-IF control diets, with similar preservation of fat-free mass.
Abstract
Type 2 diabetes mellitus (T2DM) and inactivity individually accelerate changes related to vascular aging. These changes increase cardiovascular risk and contribute to morbidity and mortality ...in the elderly. It is unknown if T2DM and bed rest have an additive, deleterious effect on vascular structure and function in older adults. The objective of this study is to determine the magnitude of the effect of bed rest on vascular structure in older adults with T2DM compared to healthy controls and determine if resistance exercise is protective of this effect. So far, we have recruited T2DM (n=9) and healthy control (n=17) subjects (age: 67.0 ± 6.7 years) to undergo five days of bed rest. During bed rest, subjects were randomized to receive intensive bedside resistance exercise physical therapy or standard of care in-bed passive physical therapy. On bed rest days 1 and 5, popliteal artery diameter, area, blood velocity, and blood flow were measured using Doppler ultrasonography. Our preliminary data show that the T2DM, non-exercise group had significantly greater decreases in popliteal artery diameter (-0.59 mm ± 0.18) than the control, non-exercise group (-0.17 mm ± 0.11). Resistance exercise did not prevent artery size changes in either controls or T2DM. Resistance exercise showed a trend in preventing blood velocity and flow reduction in both T2DM and control groups. These preliminary data suggest that older adults with T2DM had greater structural popliteal artery changes compared to controls. Resistance exercise appears to help maintain blood flow by maintaining/increasing popliteal artery blood velocity, but not size.
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