To investigate the time-course of changes in knee-extensors muscle mass, architecture and function in response to plyometric training (PLT) performed on a novel training device, the Tramp-Trainer. ...This machine consists in a trampoline connected to an inclined sledge which allows the performance of repeated jumps while the subject is sitting on a chair.
Eight healthy males (173.6 ± 4.7 cm, 69.7 ± 13.5 kg, 25.3 ± 4.6 years) underwent 6 weeks of bilateral PLT on the tramp-trainer machine. Training was performed three times per week (between 120 and 150 bounces per session). Knee-extensor maximum voluntary torque (MVT) and power, quadriceps femoris (QF) volume (VOL), cross-sectional area from the 20% to the 60% of femur length and CSA
, together with vastus lateralis (VL) architecture (fascicle length, Lf, and pennation angle, PA) were assessed after 2, 4, and 6 weeks of PLT.
All results are presented as changes versus baseline values. MVT increased by 17.8% (week 2,
< 0.001) and 22.2% (week 4,
< 0.01), respectively, and declined to 13.3% (
< 0.05) at week 6 of PLT. Power increased by 18.2% (week 4,
< 0.05) and 19.7% (week 6,
< 0.05). QF VOL increased by 4.7% (week 4,
< 0.05) and 5.8% (week 6,
< 0.01); VL VOL increased by 5.2%, (
< 0.05), 8.2%, (
< 0.01), and 9.6% (
< 0.05) at weeks 2, 4, and 6, respectively. An increase in Lf was detected already at wk 2 (2.2%,
< 0.05), with further increase at 4 and 6 weeks of PLT (4 and 4.4%, respectively,
< 0.01). PA increased by 5.8% (
< 0.05) at week 6. Significant positive correlations were found between CSA
and Power (
= 0.46,
< 0.001) and between QF VOL and Power (
= 0.44,
< 0.024).
PLT induced rapid increases in muscle volume, fascicle length, pennation angle, torque and power in healthy younger adults. Notably, changes in VL VOL and Lf were detectable already after 2 weeks, followed by increases in knee extensors VOL and power from week 4 of PLT. Since the increase in CSA
and QF VOL cannot fully explain the increment in muscle power, it is likely that other factors (such as adaptations in neural drive or tendon mechanical properties) may have contributed to such fucntional changes.
The main outcome of this review was the association between a history of clinical chronic prostatitis (NIH category II or III) and a histologically confirmed diagnosis of prostate cancer.
Crude odds ...ratios and 95% confidence intervals (CI) were calculated to analyze dichotomous data. For analysis of pooled data we adopted a random-effects model and the inverse variance weighing method. Heterogeneity was assessed by calculating the I2 value.
Out of 2794 screened records, we retrieved 16 full-text articles written in English, reporting the data of 15 case-control studies, involving 422.943 patients. Pooled analysis resulted in a significant crude odds ratio of 1.83 (95% CI: 1.43 to 2.35; P < 0.00001). The total set of data showed considerable heterogeneity (I2 = 91%). Both the Egger's test and the Begg's test for funnel plot asymmetry did not reach statistical significance. The 'trim and fill' method applied to the funnel plot imputed 3 missing studies and the resulting adjusted estimate of the odds ratio was 2.12 (95% CI: 1.38 to 3.22). According to GRADE criteria, the overall quality of the meta-analysis data is low, mainly due to the presence of bias, confounders and extreme effect size outliers. Five among the included studies reported data assessed in 8015 African-American subjects. Pooled analysis resulted in a non-significant crude odds ratio of 1.59 (95% CI: 0.71 to 3.57; P = 0.26), and considerable heterogeneity (I2 = 90%).
Meta-analysis of 15 case-control studies shows that a history of clinical chronic prostatitis can significantly increase the odds for prostate cancer in the general population, whereas such association in African-American individuals remains uncertain.
Although regular physical activity exposure leads to positive postural balance control (PBC) adaptations, few studies investigated its effects, or the one of inactivity, on PBC in populations of ...different age groups. Thus, this study investigated the impact of a physically active lifestyle on static and dynamic PBC in young and older adults. Thirty-five young physically active subjects (YA), 20 young sedentary subjects (YS), 16 physically active older adults (OA), and 15 sedentary older adults (OS) underwent a static and a dynamic PBC assessment. A force platform and an instrumented proprioceptive board were employed to measure the center of pressure (COP) trajectory and the anteroposterior oscillations, respectively. In static conditions, no significant differences were detected among groups considering the overall postural balance performance represented by the area of confidence ellipse values. Conversely, the YA highlighted a higher efficiency (i.e., lower sway path mean velocity) in PBC maintenance compared to the other groups (YA vs OA:
p
= 0.0057, Cohen’s d = 0.94; YA vs OS
p
= 0.043, d = 1.07; YA vs YS
p
= 0.08, d = 0.67). OS exhibited an overall worse performance in dynamic conditions than YA and YS. Surprisingly, no differences were found between YS and OA for all the static and dynamic parameters considered. In conclusion, our results suggest that a physically active lifestyle may promote static and dynamic balance performance in young and older adults, thus with potentially positive effects on the age-related decline of postural balance performance. Dynamic PBC assessment seems more sensitive in detecting differences between groups than the static evaluation.
Background
Inactivity and unloading induce skeletal muscle atrophy, loss of strength and detrimental metabolic effects. Bed rest is a model to study the impact of inactivity on the musculoskeletal ...system. It not only provides information for bed‐ridden patients care, but it is also a ground‐based spaceflight analogue used to mimic the challenges of long space missions for the human body. In both cases, it would be desirable to develop a panel of biomarkers to monitor muscle atrophy in a minimally invasive way at point of care to limit the onset of muscle loss in a personalized fashion.
Methods
We applied mass spectrometry‐based proteomics to measure plasma protein abundance changes in response to 10 days of bed rest in 10 young males. To validate the correlation between muscle atrophy and the significant hits emerging from our study, we analysed in parallel, with the same pipeline, a cohort of cancer patients with or without cachexia and age‐matched controls. Our analysis resulted in the quantification of over 500 proteins.
Results
Unloading affected plasma concentration of proteins of the complement cascade, lipid carriers and proteins derived from tissue leakage. Among the latter, teneurin‐4 increased 1.6‐fold in plasma at bed rest day 10 (BR10) compared with BR0 (6.E9 vs. 4.3E9, P = 0.02) and decreased to 0.6‐fold the initial abundance after 2 days of recovery at normal daily activity (R + 2, 2.7E9, P = 3.3E‐4); the extracellular matrix protein lumican was decreased to 0.7‐fold (1.2E9 vs. 8.5E8, P = 1.5E‐4) at BR10 and remained as low at R + 2. We identified six proteins distinguishing subjects developing unloading‐mediated muscle atrophy (decrease of >4% of quadriceps cross‐sectional area) from those largely maintaining their initial muscle mass. Among them, transthyretin, a thyroid hormone‐binding protein, was significantly less abundant at BR10 in the plasma of subjects with muscle atrophy compared with those with no atrophy (1.6E10 vs. 2.6E10, P = 0.001). Haptoglobin‐related protein was also significantly reduced in the serum of cancer patients with cachexia compared with that of controls.
Conclusions
Our findings highlight a combination or proteomic changes that can be explored as potential biomarkers of muscle atrophy occurring under different conditions. The panel of significant proteomic differences distinguishing atrophy‐prone and atrophy‐resistant subjects after 10 days of bed rest need to be tested in a larger cohort to validate their potential to predict inactivity‐triggered muscle loss in humans.
Over recent years, several reports have been published on unusual cases of osteonecrosis of the jaw (ONJ) in adults using second- and third-generation nitrogen-containing bisphosphonates such as ...pamidronate, alendronate, risedronate and zoledronate, but no case has ever been reported either in children or in adult patients taking neridronate. Children and adolescents affected by osteogenesis imperfecta (OI) could belong to a high-risk group for ONJ because bone fragility in OI is associated with a connective tissue malfunction. The purpose of this study is to evaluate the incidence of ONJ in a pediatric population treated with neridronate for OI. A total of 102 pediatric patients with OI who received neridronate infusions for a mean of 6.81 years (SD ± 3.06 years) were clinically assessed for possible ONJ. Eligibility criteria for participation included patients between 1.2 and 24 years old who received cyclical neridronate infusions for at least 1 year. All the patients were reviewed to determine duration, dosage and cumulative dose of their bisphosphonate therapy and were examined clinically to assess their oral health status. We have not demonstrated any occurrence of ONJ in our patients. In conclusion, at the moment insufficient data are available to prove a greater risk of ONJ in children with OI than in children affected by other forms of bone fragility. However, cases may emerge in future because the risk of ONJ seems to be related to the cumulative dose and the duration of therapy.
Background
Ageing is accompanied by a progressive loss of skeletal muscle mass and strength, potentially determining the insurgence of sarcopenia. Evidence suggests that motoneuron and neuromuscular ...junction (NMJ) degeneration contribute to sarcopenia pathogenesis. Seeking for strategies able to slow down sarcopenia insurgence and progression, we investigated whether a 2‐year mixed‐model training involving aerobic, strength and balance exercises would be effective for improving or preserving motoneuronal health and NMJ stability, together with muscle mass, strength and functionality in an old, sarcopenic population.
Methods
Forty‐five sarcopenic elderly (34 females; 11 males) with low dual‐energy X‐ray absorptiometry (DXA) lean mass and Short Physical Performance Battery (SPPB) score <9 were randomly assigned to either a control group Healthy Aging Lifestyle Education (HALE), n = 21 or an intervention group MultiComponent Intervention (MCI), n = 24. MCI trained three times per week for 2 years with a mix of aerobic, strength and balance exercises matched with nutritional advice. Before and after the intervention, ultrasound scans of the vastus lateralis (VL), SPPB and a blood sample were obtained. VL architecture pennation angle (PA) and fascicle length (Lf) and cross‐sectional area (CSA) were measured. As biomarkers of neuronal health and NMJ stability status, neurofilament light chain (NfL) and C‐terminal agrin fragment (CAF) concentrations were measured in serum. Differences in ultrasound parameters, NfL and CAF concentration and physical performance between baseline and follow‐up were tested with mixed ANOVA or Wilcoxon test. The relationship between changes in physical performance and NfL or CAF concentration was assessed through correlation analyses.
Results
At follow‐up, MCI showed preserved VL architecture (PA, Lf) despite a reduced CSA (−8.4%, P < 0.001), accompanied by maintained CAF concentration and ameliorated overall SPPB performance (P = 0.007). Conversely, HALE showed 12.7% decrease in muscle CSA (P < 0.001), together with 5.1% and 5.5% reduction in PA and Lf (P < 0.001 and P = 0.001, respectively), and a 6.2% increase in CAF (P = 0.009) but improved SPPB balance score (P = 0.007). NfL concentration did not change in either group. In the population, negative correlations between changes in CAF concentration and SPPB total score were found (P = 0.047), whereas no correlation between NfL and SPPB variations was observed.
Conclusions
The present findings suggest that our 2‐year mixed aerobic, strength and balance training seemed effective for preventing the age and sarcopenia‐related increases in CAF concentration, preserving NMJ stability as well as muscle structure (PA and Lf) and improving physical performance in sarcopenic older individuals.
Purpose:
Fascicle and sarcomere lengths are important predictors of muscle mechanical performance. However, their regulation during stretch-shortening cycle (SSC) activities in usual and challenging ...conditions is poorly understood. In this study, we aimed to investigate muscle fascicle and sarcomere behavior during drop jumps (a common SSC activity) in conditions of variable gravity.
Methods:
Fifteen volunteers performed repeated drop jumps in 1 g, hypo-gravity (0 to 1 g), and hyper-gravity (1 to 2 g) during a parabolic flight. Gastrocnemius medialis (GM) electromyographic activity and fascicle length (Lf) were measured at drop-off, ground contact (GC), minimum ankle joint angle (MAJ), and push-off. GM sarcomere number was estimated by dividing Lf, measured by ultrasound at rest, by published data on GM sarcomere length, and measured
in vivo
at the same joint angle. Changes in sarcomere length were estimated by dividing GM Lf in each jump phase by sarcomere number calculated individually. The sarcomere force-generating capacity in each jump phase was estimated from the sarcomere length-tension relationship previously reported in the literature.
Results:
The results showed that, regardless of the gravity level, GM sarcomeres operated in the ascending portion of their length-tension relationship in all the jump phases. Interestingly, although in hypo-gravity and hyper-gravity during the braking phase (GC-MAJ) GM fascicles and sarcomeres experienced a stretch (as opposed to the quasi-isometric behavior in 1 g), at MAJ they reached similar lengths as in 1 g, allowing sarcomeres to develop about the 70% of their maximum force.
Conclusion:
The observed fascicle behavior during drop jumping seems useful for anchoring the tendon, enabling storage of elastic energy and its release in the subsequent push-off phase for effectively re-bouncing in all gravity levels, suggesting that an innate neuromuscular wisdom enables to perform SSC movements also in challenging conditions.
ObjectiveTo verify the effects of bisphosphonates (Bps) in combination with recombinant human GH (rGH) in pediatric osteogenesis imperfecta (OI) patients; we focused on possible improvement of bone ...mineral density (BMD), projected bone areas, growth velocity, and fractures risk.DesignA randomized controlled 1-year clinical trial on 30 prepubertal children (M:F=14:16) affected by OI (type I, IV, and III) being treated with neridronate.MethodsFollowing an observational period of 12 months during ongoing neridronate treatment, the patients were randomly divided into two groups: 15 were treated for 12 months with rGH and neridronate (group Bp+rGH) and 15 continued neridronate alone (group Bp). We evaluated auxological parameters, number of fractures, bone age (BA), bone metabolic parameters, and bone mass measurements (at lumbar spine and radius by dual-energy X-ray absorptiometry).ResultsThe mean variation in percentage of BMD (Δ%BMD) – at lumbar spine (L2–L4), at distal and ultradistal radius – and the projected area of lumbar spine increased significantly in group Bp+rGH (P<0.05). Growth velocity was significantly higher during rGH treatment in group Bp+rGH versus group Bp and versus pretreatment (P<0.05), with no difference in increase in BA or fracture risk rate. Patients with quantitative (-qt) collagen synthesis defects had a higher, although not significant, response to rGH in terms of growth velocity and BMD.ConclusionsIn OI patients, the combined rGH–Bp treatment may give better results than Bp treatment alone, in terms of BMD, lumbar spine projected area and growth velocity, particularly in patients with quantitative defects.
Eight difluoro-bora-diaza-s-indacenes (BODIPY dyes) were synthesized and characterized for their physicochemical properties. The photoxicity of these photosensitizers (PSs) was assessed on the human ...colon carcinoma cell line HCT116. To elucidate some aspects of the PS-induced phototoxicity, flow cytometric analysis of the percentage of apoptotic and autophagic cells was performed . Display omitted
► Synthesis and photodynamic activity of a panel of eight BODIPYs (PSs). ► Physico-chemical data about singlet oxygen, fluorescence and lipophilicity. ► Nano-molar IC50 values photo induced killing effect against HCT116 cell line. ► The most efficient PS was exploited against MCF7, A2780 and A2780/CP8 cell lines.
Eight BODIPY dyes were synthesized and used as photosensitizers (PSs) on the human colon carcinoma cell line HCT116. In this panel of molecules, the structure varies in the substituents on pyrrole 2, 6 positions and on the phenyl ring at the indacene 8 position. For these compounds relevant physico-chemical parameters, such as singlet oxygen production, fluorescent quantum yield, absorbance profile and a relative rank of lipophilicity were determined.
Our results indicate that some of these novel PSs are very effective in reducing the growth/viability of HCT116 cells when irradiated with a green LED source, whereas they are practically devoid of activity in the dark, up to 5μM. To evaluate whether cell death is induced under these conditions, flow cytometric analysis of the percentage of apoptotic and autophagic cells was performed on four molecules, chosen for their efficacy/structural characteristics. Our data indicate that phototoxicity likely occurs mainly through apoptotic cell death, whereas autophagy seems to play a minor role in determining cell fate. Furthermore, the relationship between singlet oxygen generation and the PS efficacy is confirmed, thus underscoring the importance of the heavy-atom effect and of the presence of an aryl substituent at dipyrromethene 8 (meso) position.
Among the PSs here described, the most efficient BODIPY was successfully tested on three other human cancer cell lines of different tissue origin, MCF7 (breast), A2780 and A2780/CP8 (ovary, sensitive and resistant to cisplatin, respectively), yielding IC50 values comparable to those obtained on HCT116.
The preservation of muscle power is crucial in aging for maintaining mobility and performing daily tasks. Resistance training involving high movement velocities represents a valid strategy to slow ...down the rate of sarcopenia, counteracting the loss of muscle mass and muscle power. Plyometric exercise may represent an effective training modality for increasing muscle power; however, its application in older populations has been sparingly investigated, as the high impact actions involved may reduce its feasibility for older individuals. By adopting a safer modality of plyometric training, we investigated if a 6-week plyometric training intervention could increase knee extensor muscle size, architecture, force and power in 14 young (YM, age = 25.4 ± 3.5 y; means ± SD) and nine older males (OM, age = 69.7 ± 3.4 y). Volunteers trained 3 times/week using a device similar to a leg press machine where the user was required to bounce against his body mass on a trampoline. Pre-to-post training changes in isometric maximum voluntary torque (MVT), leg extension power and vastus lateralis (VL) architecture were assessed. Muscle power increased in both groups (+27% OM -
< 0.001, 20% YM -
< 0.001), although the total external work performed during the training period was significantly lower for OM (i.e., ~-47%). Both groups showed significant increases in muscle thickness (MT) (+5.8 OM -
< 0.01 vs. +3.8% YM -
< 0.01), fascicle length (Lf) (+8% OM -
< 0.001 vs. +6% YM -
< 0.001), and pennation angle (PA) (+7.5% OM -
< 0.001 vs. +4.1% YM -
< 0.001). The current study shows that trampoline-based plyometric training is an effective intervention producing a rapid increase in muscle mass and power in both young and older individuals. The training modality used in this study seems to particularly benefit the older population, targeting the morphological and functional effects of sarcopenia in human muscle.
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