Reduction in the risk of progression of solid organ transplant recipients infected by SARS-CoV-2 treated with monoclonal antibodies.

Recipients of solid organ transplants (SOT) are at higher risk of infection by SARS-CoV-2 virus especially due to chronic immunosuppression therapy and frequent multiple comorbid conditions. COVID-19 is a potentially life-threatening disease in SOT recipients, with an increased likelihood of progressing to severe disease, with the need of hospitalization, admission to the intensive care unit (ICU) and mechanical ventilatory support. This article presents an updated review of different aspects related to the outcome of COVID-19 in SOT recipients. In nvaccinated SOT recipients, COVID-19 is associated with a high mortality rate, in-patient care and ICU admission, and impaired graft function or rejection in severe disease. In vaccinated SOT recipients even after full vaccination, there is a reduction of the risk of mortality, but the course of COVID-19 may continue to be severe, influenced by the time from transplant, the net state of immunosuppression and having suffered graft rejection or dysfunction. SOT recipients develop lower immunity from mRNA vaccines with suboptimal response. Treatment with mAbs provides favorable outcomes in non-hospitalized SOT recipients at high risk for severe disease, with lower rates of hospitalization, emergency department visits, ICU care, progression to severe disease, and death. However, broad vaccination and therapeutic options are required, particularly in light of the tendency of the SARS-CoV-2 virus to adapt and evade both natural and vaccine-induced immunity.

Home-based exercise in autoimmune myasthenia gravis: A randomized controlled trial.

The tolerance of exercise and its effects on quality of life in myasthenia gravis are not currently backed up by strong evidence. The aim of this study was to determine whether exercise as an adjunct therapy is well tolerated and can improve health-related quality of life (HRQoL) in stabilized, generalized autoimmune myasthenia gravis (gMG). We conducted a parallel-group, multi-center prospective RCT using computer-generated block randomization. Adults with stabilized, gMG, and no contra-indication to exercise, were eligible. Participants received usual care alone or usual care and exercise. The exercise intervention consisted of 3-weekly 40 min sessions of an unsupervised, moderate-intensity home rowing program over 3 months. The primary endpoint was the change in HRQoL from randomization to post-intervention. Assessor-blinded secondary endpoints were exercise tolerance and effects on clinical, psychological and immunological status. Of 138 patients screened between October 2014 and July 2017, 45 were randomly assigned to exercise (n = 23) or usual care (n = 20). Although exercise was well tolerated, the intention-to-treat analysis revealed no evidence of improved HRQoL compared to usual care (MGQOL-15-F; mean adjusted between-groups difference of -0.8 points, 95%CI -5.4 to 3.7). Two patients hospitalized for MG exacerbation were from the usual care group.

Effectiveness of exercise training after bariatric surgery-a systematic literature review and meta-analysis.

We aimed to conduct a systematic review and meta-analysis of controlled trials assessing exercise training programs in patients with obesity undergoing bariatric surgery. We systematically searched exercise training studies performed after bariatric surgery published up to June 2017. Studies reporting changes in body composition, physical fitness, functional capacity, objectively measured physical activity, quality of life or relevant health outcomes were included. The review protocol is available from PROSPERO (CRD42017069380). Meta-analyses were conducted using random-effects models when data were available from at least five articles. Twenty articles were included, describing 16 exercise training programs, of which 15 were included in the meta-analysis. Overall, exercise training was associated with higher weight loss (mean difference: -2.4 kg, 95% CI: -4.2; -0.6, I2  = 49%, n = 12), higher fat mass loss (-2.7 kg, 95% CI: -4.5; -1.0, I2  = 50%, n = 8) and improved VO2 max and functional walking (standardized mean difference: 0.86, 95% CI: 0.29; 1.44, I2  = 57%, n = 6; 1.45, 95% CI: 0.32; 2.58, I2  = 89%, n = 6, respectively). Exercise training was not associated with lean body mass changes. In conclusion, exercise training programs performed after bariatric surgery were found effective to optimize weight loss and fat mass loss and to improve physical fitness, although no additional effect on lean body mass loss was found.

Influence of radiopacity of dental composites on the diagnosis of secondary caries: the correlation between objective and subjective analyses.

This study aimed to objectively evaluate the radiopacity of different dental composites and their subjective influence on diagnosing secondary caries-like lesions and how these results correlate. For objective analysis, three resin specimens (1 mm thick, with a 4-mm internal diameter) were made with four composites: 1) Charisma; 2) Filtek Z250; 3) Prisma AP.H; and 4) Glacier. Three human teeth were selected and then mesio-distally sectioned (1 mm thick) to make the dental specimens. An aluminum (Al) wedge (12 steps, 1 mm thick, 99.8% purity) was used as an internal standard to calculate the radiopacity. For subjective analysis, 20 human teeth were selected and then prepared with a mesio-occluso-distal (MOD) inlay cavity, with half the teeth receiving a round cavity to simulate the carious lesion. The MOD was restored using the composites at four different times. Standardized radiographs were acquired and then digitized (300 dpi and eight-bit TIFF) for both analyses. A histogram objectively measured the pixel intensity values of the images, which were converted into millimeters of Al using linear regressions. Eight observers subjectively evaluated the images using a five-point rating scale to diagnose the caries. The data were statistically analyzed using the Student t-test, the Kappa test, diagnostic testing, and the Pearson correlation coefficient (α=0.05). All materials showed radiopacity values compatible with dental tissues (p>0.05); Glacier was similar to dentin and Prisma AP.H was similar to enamel, while the remaining materials showed a middle radiopacity. Prisma AP.H and Glacier differed (p<0.05) in relation to their accuracy to caries diagnosis, with Glacier having greater accuracy. There was a correlation between objective and subjective analyses with negative linear dependence. An increase in the material's radiopacity could have a subjectively negative influence on the diagnosis of secondary caries; thus, an ideal radiopacity for a dental composite is closer to the dentin image and produces similar attenuation to X-rays than does dentin.

Posture and equilibrium in orthopedic and rheumatologic diseases.

Posture and balance may be affected in many spine or lower-limb disorders. An extensive evaluation including clinical tests and movement analysis techniques may be necessary to characterize how rheumatologic or orthopedic diseases are related to static or dynamic changes in postural control. In lower limbs, unbalance may be related to a decreased stability following arthrosis or ligament injuries at knee or ankle levels, while hip lesions appear less associated with such troubles. Spinal diseases at cervical level are frequently associated with postural changes and impaired balance control, related to the major role of sensory inputs during stance and gait. At lower levels, changes are noticed in major scoliosis and may be related to pain intensity in patients with chronic low-back pain. Whatever the initial lesion and the affected level, improvement in clinical or instrumental tests following rehabilitation or brace wearing provides argument for a close relationship between rheumatologic or orthopedic diseases and related impairments in posture and balance control.

Changes in balance and strength parameters induced by training on a motorised rotating platform: a study on healthy subjects.

AIM: The aim of the present study was to analyse the effects of training performed on a rotating, motorised platform (the Huber/SpineForce device from LPG Systems, Valence, France) intended to improve, postural control and muscle function. SUBJECTS: Twelve healthy adults (divided into a sedentary group and an active group) took part in a two-month training programme (involving three sessions a week) on the SpineForce whole body rehabilitation device. METHOD: Instrumental assessment of postural control (on a Satel platform) and muscle function (on a Cybex Norm) was performed before and after training. Postural control in various conditions was measured using a position parameter (the mean anteroposterior position of the centre of foot pressure [CoP]) and two stability parameters (maximum CoP displacement and CoP sway area). Assessment of the muscle function was performed during knee and spine extension and featured maximum voluntary isometric contraction (MVIC), root mean square (RMS) and neuromuscular efficiency (MVIC/RMS) measurements. RESULTS: For static postural control, we observed a more forward CoP position in the maximum backward inclination condition (p<0.01) and a decrease in maximum CoP displacement in the "eyes closed on foam" and "maximum anterior inclination" conditions. In this latter condition, a lower CoP sway area was also noted (p<0.01). In terms of muscle function, a greater MVIC for knee extension was observed in the sedentary group only (p<0.05). These changes were not correlated with each another (p<0.05). However, the value of the pretraining maximum CoP displacement predicted its final value (p<0.05). CONCLUSION: Our results suggest that static postural control responds to training on a Huber((R))/SpineForce rehabilitation device. It seems probable that a population with a low initial level of physical activity would benefit most from training on this type of device. This training could notably be applied to elderly or disabled people and especially those with sensorimotor disabilities.

[Neuromuscular and architectural alterations of the vastus lateralis muscle in elderly patients with unilateral knee osteoarthritis]. / Altérations architecturales et neuromusculaires du muscle vastus lateralis chez des patients âgés atteints de gonarthrose unilatérale.

AIM: The aim of this study was to determine the mechanisms involved in muscle weakness in elderly patients with unilateral knee osteoarthritis. SUBJECTS: We investigated 7 patients with unilateral knee osteoarthritis. METHOD: We measured knee position sense and isometric maximal voluntary contraction (MVC) of the knee extensors. Electromyographic (EMG) measurement of biceps femoris (BF), rectus femoris (RF), vastus lateralis (VL) and vastus medialis (VM) involved different levels of contraction (25, 50, 75 and 100% MVC). Neuromuscular efficiency of quadriceps was also calculated (MVC/EMG). Ultrasonography was used to investigate the VL architectural parameters at the median part of the VL for different levels of contraction (25, 50, and 75% MVC). All tests were performed on the osteoarthritic and healthy knees. RESULTS: The quadriceps MVC of the affected knee was reduced by 30%. The VL thickness of the affected knee was 10% smaller than that of the unaffected knee. VL activity seen on EMG did not differ between knees, but RF, VM and BF activity was greater in the unaffected than affected knee. Neuromuscular efficiency was higher (26%) in the unaffected knee. Knee position sense was reduced by 33% in the affected knee. CONCLUSION: Quadriceps weakness associated with knee osteoarthritis seems to be related to changes in muscle rather than pennation angle and changes in fascicule length.

Effects of resistance training in humans on neck muscle performance, and electromyogram power spectrum changes.

The purpose of this study was to quantify the neuromuscular cervical adaptations to an 8 week strength training programme. Seven healthy men, with no pathological conditions of the neck, performed a lateral flexion isometric resistance-training programme three times a week. The training sessions consisted of one set of ten contractions, each of 6 s duration, at 60% of the predetermined maximal voluntary isometric torque (MVTim) (warm-up) and two sets of eight contractions, each of 6 s duration, at 80% MVTim. The training effects were evaluated in three ways: muscle size, strength and fatigability. The cross-sectional areas (CSA) of the trapezius (TRP) and sternocleidomastoideus (SCM) muscles were determined using a computerised tomographic scanner. Results showed an increase in the CSA of TRP and SCM muscles after training, 8.8% at C5 level and 6.4% at C7 level for SCM muscle and 12.2% at C7 level for TRP muscle. Strength increased significantly under both isometric and isokinetic conditions (35% and 20%, respectively). Muscle fatigability in lateral flexion was quantified during a sustained isometric contraction at 50% of MVTim. The shift of the mean power frequency of the electromyogram power spectrum density function of SCM muscle toward lower frequencies was less after training (14.6% compared to 6.8%). These results indicate the beneficial effect of a strength-training programme which increases neck muscle size and strength during lateral flexion, and decreases the fatigability of the superficial muscles of the neck.

Nutrient intake of elite sailors during a solitary long-distance offshore race.

The purpose of the present study was to determine the nutritional intake of 11 skippers during the four stages of a solitary long-distance offshore race. Body weight significantly decreased during the race (-1.31 +/- 0.32 kg, range 3.5 to 0.1 kg, p <.01). Total daily energy intake was 18.53 +/- 0.71 MJ x day-1 during the race, and it correlated negatively with the rate duration of each leg. Energy intake during the race was 19% greater than that determined for a subgroup of 5 sailors during a control period 2 months after the race. Nutrient intake expressed as percentage calories of total energy was estimated at 50%, 35%, and 15% for carbohydrate, fat, and protein, respectively. Voluntary fluid intake decreased with increasing race duration (p<.001). Despite high energy intakes, sailors lost body weight during the solitary offshore race. It was not possible to conclude that this change in body weight was related to fluid loss and/or a discrepancy between energy intake and energy expenditure.

Surface electromyogram power spectrum changes in human leg muscles following 4 weeks of simulated microgravity.

Surface electromyogram (EMG) spectrum changes in human tibialis anterior (TA) and gastrocnemius medialis (GM) muscles were studied to investigate the effect of 4-week bed rest (BR) on muscle fatigability. An exhausting isometric test at 50% of the maximal voluntary contraction was performed by 12 clinically healthy men before and after BR. During this test, mean power frequency (MPF) calculated from surface EMG decreased linearly for TA and GM. When changes in MPF were expressed in terms of rate of decrease a significant difference appeared between TA and GM. Furthermore, as a result of BR, the shift in MPF increased significantly for GM (6.1% vs 10.4%) whereas it was not significantly changed for TA (28.6% vs 20.95%). Alterations in maximal torque were also observed with a more pronounced decrease for plantar-flexor (20.5%) compared with dorsiflexor (15.1%) muscles. These results would seen: to indicate that simulated microgravity preferentially affects muscles having an antigravity function.

Electromyogram spectrum changes during sustained contraction related to proton and diprotonated inorganic phosphate accumulation: a 31P nuclear magnetic resonance study on human calf muscles.

The calf muscles of five clinically healthy men were submitted to isometric exercise and examined by 31P nuclear magnetic resonance (NMR) spectroscopy and electromyography (EMG) to evaluate the influence of proton (H+) and diprotonated forms of inorganic phosphate (H2PO4-) accumulation on EMG spectrum changes. The experiments were performed in a supra-conducting magnet (2.35 Tesla, 35-cm effective diameter) using a surface coil (7-cm diameter) positioned against the calf muscles. The EMG surface electrodes were applied on the gastrocnemius medialis muscle and acquisition of both NMR and EMG signals was synchronized. The exercise consisted of a sustained isometric contraction at 70% of the maximal voluntary contraction until exhaustion. A continuous decrease in phosphocreatine content and a large concomitant increase in H2PO4- was observed in the calf muscles of each subject. A significant increase in H+ concentration was also found when considering the whole population but intracellular acidosis was low for two subjects. Moreover, a quasilinear decrease in mean power frequency (MPF) was found during the test. Changes in MPF were correlated with variations in H+ and H2PO4- concentration but a more significant relationship was found when MPF changes were correlated with H2PO4- concentration. An interpretation of EMG spectrum changes in terms of an accumulation of by-products of anaerobic metabolism and an increase in the relative number of activated slow fibres is proposed.

In situ NADH laser fluorimetry during muscle contraction in humans.

The aim of the present study was to use nicotinamide adenine dinucleotide phosphate, reduced (NADH) fluorimetry, to investigate in situ NADH changes during muscle contraction in humans on an isokinetic dynamometer. Thirteen healthy male subjects each performed one maximal voluntary contraction (MVC) with the knee extensor muscle. The NADH muscle fluorescence was monitored by a double beam laser fluorimeter which uses an optical fibre, percutaneously inserted through a needle into the vastus lateral muscle, to guide the light. The NADH fluorescence was continuously measured at a wavelength of 337 nm. To estimate the haemodynamic artefact, blood backscattering was simultaneously determined at a wavelength of 586 nm. The fluorescence signal was recorded before, during and after contractions at 50% of MVC. The fibre was kept out of contact with the muscle during contractions at 100% of MVC and was only put into contact with it at the end of the contraction. At the onset of contractions at 50% of MVC, NADH fluorescence increased rapidly for 3 s and remained stable thereafter until exhaustion. After a muscle measurement had been made, the optical fibre was put successively into solutions of increasing NADH concentration to ascertain the relationship between the muscle fluorescence signal and the muscle NADH level. This procedure yielded estimated mean values for muscle NADH of 0.172 mmol.kg-1, SEM 0.028 and of 0.184 mmol.kg-1, SEM 0.027 after contractions at 50% and 100% of MVC, respectively, from a resting value of 0.087 mmol.kg-1, SEM 0.015. These results indicated that in situ laser fluorimetry could be used to evaluate NADH changes in humans during muscle contraction.(ABSTRACT TRUNCATED AT 250 WORDS)

Metabolic and hormonal responses to lipid and carbohydrate diets during exercise in man.

Nine healthy subjects were studied to determine their performance and the metabolic and hormonal responses to prolonged exercise after ingestion of a carbohydrate or a lipid diet. Subjects exercised on a bicycle ergometer (60% VO2max) until exhaustion four times at weekly intervals. The exercise test was performed 1 h after ingestion of three different isocaloric meals (400 Kcal) containing either glucose, medium-chain triglycerides (MCTs) or long-chain triglycerides (LCTs). The fourth test was performed after a night fast. The metabolism of these nutriments was followed using [U-13C]glucose, [1-13C]octanoate, and [1-13C]palmitate added as tracers. The average work time was comparable whatever nutriment used (116 +/- 11 min). Oxidation of the ingested nutriment over this period was 80% for glucose, 45% for MCTs, and 9% for LCTs. Glucose ingestion produced an early insulin peak associated at the end of the exercise with a lower glycemia compared to the fat diets. After MCT ingestion, an increase in ketone bodies was observed. Catecholamine response to physical exercise was decreased by all the meals when compared to fasting. Thus, we conclude that a different lipid meal, MCTs, or LCTs, compared to glucose feeding, do not modify exhaustion time in spite of differences in hormonal and metabolic responses.