The Role of Footwear, Foot Orthosis and Training-Related Strategies in the Prevention of Bone Stress Injuries: A Systematic Review and Meta-Analysis

International Journal of Exercise Science 16(3): 721-743, 2023. Objective: To evaluate the effectiveness of footwear, foot orthoses and training-related strategies to prevent lower extremity bone stress injury (BSI). Design: Systematic review and meta-analysis. Data sources: Four bibliographic databases (from inception until November 2021): Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE and CINAHL. Eligibility criteria: Randomised controlled trials (RCTs) that assessed the risk of developing a BSI when using particular footwear, foot orthoses or training-related strategies such as muscle strengthening, stretching, and mechanical loading exercises. Results: Eleven studies were included in this systematic review. When wearing foot orthoses, the risk ratio of developing a BSI on any lower extremity bone is 0.47 (95% CI 0.26 to 0.87; p = 0.02). When doing pre-exercise dynamic stretching, the risk ratio of suffering a tibial BSI is 1.06 (95% CI 0.67 to 1.68; p = 0.79). No meta-analyses could be performed for footwear or training-related strategies. The quality of evidence for all these results is low considering the high risk of bias in each study, the low number of studies and the low number of cases in each study. Conclusion: This systematic review reveals the lack of high-quality studies in BSI prevention. Based on studies at high risk of bias, foot orthoses could potentially help prevent BSIs in the military setting. It is still unknown whether footwear and training-related strategies have any benefits. It is crucial to further investigate potential BSI prevention strategies in women and athletes. Research is also needed to assess the influence of running shoes and loading management on BSI incidence

Impact reduction during running: efficiency of simple acute interventions in recreational runners

International audienceRunning-related stress fractures have been associated with the overall impact intensity, which has recently been described through the loading rate (LR). Our purpose was to evaluate the effects of four acute interventions with specific focus on LR: wearing racing shoes (RACE), increasing step frequency by 10 % (FREQ), adopting a midfoot strike pattern (MIDFOOT) and combining these three interventions (COMBI). Nine rearfoot-strike subjects performed five 5-min trials during which running kinetics, kinematics and spring-mass behavior were measured for ten consecutive steps on an instrumented treadmill. Electromyographic activity of gastrocnemius lateralis, tibialis anterior, biceps femoris and vastus lateralis muscles was quantified over different phases of the stride cycle. LR was significantly and similarly reduced in MIDFOOT (37.4 ± 7.20 BW s(-1), -56.9 ± 50.0 %) and COMBI (36.8 ± 7.15 BW s(-1), -55.6 ± 29.2 %) conditions compared to NORM (56.3 ± 11.5 BW s(-1), both P<0.001). RACE (51.1 ± 9.81 BW s(-1)) and FREQ (52.7 ± 11.0 BW s(-1)) conditions had no significant effects on LR. Running with a midfoot strike pattern resulted in a significant increase in gastrocnemius lateralis pre-activation (208 ± 97.4 %, P<0.05) and in a significant decrease in tibialis anterior EMG activity (56.2 ± 15.5 %, P<0.05) averaged over the entire stride cycle. The acute attenuation of foot-ground impact seems to be mostly related to the use of a midfoot strike pattern and to a higher pre-activation of the gastrocnemius lateralis. Further studies are needed to test these results in prolonged running exercises and in the long term

Metabolic and performance responses of male runners wearing 3 types of footwear: Nike Vaporfly 4%, Saucony Endorphin racing flats, and their own shoes

Purpose We compared running economy (RE) and 3-km time-trial (TT) variables of runners wearing Nike Vaporfly 4% (VP4), Saucony Endorphin lightweight racing flats (FLAT), and their habitual running (OWN) footwear. Methods Eighteen male recreational runners (age = 33.5 ± 11.9 year (mean ± SD), peak oxygen uptake (VO2peak) = 55.8 ± 4.4 mL/kg·min) attended 4 sessions approximately 7 days apart. The first session consisted of a VO2peak test to inform subsequent RE speeds set at 60%, 70%, and 80% of the speed eliciting VO2peak. In subsequent sessions, treadmill RE and 3-km TTs were assessed in the 3 footwear conditions in a randomized, counterbalanced crossover design. Results Oxygen consumption (mL/kg·min) was less in VP4 (from 4.3% to 4.4%, p ≤ 0.002) and FLAT (from 2.7% to 3.4%, p ≤ 0.092) vs. OWN across intensities, with a non-significant difference between VP4 and FLAT (1.0%–1.7%, p ≥ 0.292). Findings related to energy cost (W/kg) and energetics cost of transport (J/kg·m) were comparable. VP4 3-km TT performance (11:07.6 ± 0:56.6 mm:ss) was enhanced vs. OWN by 16.6 s (2.4%, p = 0.005) and vs. FLAT by 13.0 s (1.8%, p = 0.032). The 3-km times between OWN and FLAT (0.5%, p = 0.747) were similar. Most runners (n = 11, 61%) ran their fastest TT in VP4. Conclusion Overall, VP4 improved laboratory-based RE measures in male recreational runners at relative speeds compared to OWN, but the RE improvements in VP4 were not significant vs. FLAT. More runners exhibited better treadmill TT performances in VP4 (61%) vs. FLAT (22%) and OWN (17%). The variability in RE (–10.3% to 13.3%) and TT (–4.7% to 9.3%) improvements suggests that responses to different types of shoes are individualized and warrant further investigation

Kinematics of recreational male runners in "super", minimalist and habitual shoes

We conducted an exploratory analysis to compare running kinematics of 16 male recreational runners wearing Nike Vaporfly 4% (VP4), Saucony Endorphin racing flat (FLAT), and their habitual (OWN) footwear. We also explored potential relationships between kinematic and physiological changes. Runners (age: 33 ± 12 y, V _O2peak: 55.2 ± 4.3 ml · kg−1·min−1) attended 3 sessions after completing an V _ O2peak test in which sagittal plane 3D kinematics at submaximal running speeds (60%, 70% and 80% ʋ V _ O2peak) were collected alongside economy measures. Kinematics were compared using notched boxplots, and between-shoe kinematic differences were plotted against between-shoe economy differences. Across intensities, VP4 involved longer flight times (6.7 to 10.0 ms) and lower stance hip range of motion (~3°), and greater vertical pelvis displacement than FLAT (~0.4 cm). Peak dorsiflexion angles (~2°), ankle range of motion (1.0° to 3.9°), and plantarflexion velocities (11.3 to 89.0 deg · sec−1) were greatest in FLAT and lowest in VP4. Foot-ground angles were smaller in FLAT (2.5° to 3.6°). Select kinematic variables were moderately related to economy, with higher step frequencies and longer step lengths in VP4 and FLAT associated with improved economy versus OWN. Footwear changes from OWN altered running kinematics. The most pronounced differences were observed in ankle, spatiotemporal, and foot-ground angle variables

Structure of an archaeal non-discriminating glutamyl-tRNA synthetase: a missing link in the evolution of Gln-tRNAGln formation

The molecular basis of the genetic code relies on the specific ligation of amino acids to their cognate tRNA molecules. However, two pathways exist for the formation of Gln-tRNAGln. The evolutionarily older indirect route utilizes a non-discriminating glutamyl-tRNA synthetase (ND-GluRS) that can form both Glu-tRNAGlu and Glu-tRNAGln. The Glu-tRNAGln is then converted to Gln-tRNAGln by an amidotransferase. Since the well-characterized bacterial ND-GluRS enzymes recognize tRNAGlu and tRNAGln with an unrelated α-helical cage domain in contrast to the β-barrel anticodon-binding domain in archaeal and eukaryotic GluRSs, the mode of tRNAGlu/tRNAGln discrimination in archaea and eukaryotes was unknown. Here, we present the crystal structure of the Methanothermobacter thermautotrophicus ND-GluRS, which is the evolutionary predecessor of both the glutaminyl-tRNA synthetase (GlnRS) and the eukaryotic discriminating GluRS. Comparison with the previously solved structure of the Escherichia coli GlnRS-tRNAGln complex reveals the structural determinants responsible for specific tRNAGln recognition by GlnRS compared to promiscuous recognition of both tRNAs by the ND-GluRS. The structure also shows the amino acid recognition pocket of GluRS is more variable than that found in GlnRS. Phylogenetic analysis is used to reconstruct the key events in the evolution from indirect to direct genetic encoding of glutamine

Evaluation of the Safety and Immunogenicity of the RTS,S/AS01E Malaria Candidate Vaccine When Integrated in the Expanded Program of Immunization

Background. The RTS,S/AS01E malaria candidate vaccine is being developed for immunization of African infants through the Expanded Program of Immunization (EPI). Methods. This phase 2, randomized, open, controlled trial conducted in Ghana, Tanzania, and Gabon evaluated the safety and immunogenicity of RTS,S/AS01E when coadministered with EPI vaccines. Five hundred eleven infants were randomized to receive RTS,S/AS01E at 0, 1, and 2 months (in 3 doses with diphtheria, tetanus, and wholecell pertussis conjugate [DTPw]; hepatitis B [HepB]; Haemophilus influenzae type b [Hib]; and oral polio vaccine [OPV]), RTS,S/AS01E at 0, 1, and 7 months (2 doses with DTPwHepB/Hib+OPV and 1 dose with measles and yellow fever), or EPI vaccines only. Results. The occurrences of serious adverse events were balanced across groups; none were vaccine-related. One child from the control group died. Mild to moderate fever and diaper dermatitis occurred more frequently in the RTS,S/AS01E coadministration groups. RTS,S/AS01E generated high anti-circumsporozoite protein and anti- hepatitis B surface antigen antibody levels. Regarding EPI vaccine responses upon coadministration when considering both immunization schedules, despite a tendency toward lower geometric mean titers to some EPI antigens, predefined noninferiority criteria were met for all EPI antigens except for polio 3 when EPI vaccines were given with RTS,S/AS01E at 0, 1, and 2 months. However, when antibody levels at screening were taken into account, the rates of response to polio 3 antigens were comparable between groups. Conclusion. RTS,S/AS01E integrated in the EPI showed a favorable safety and immunogenicity evaluation. Trial registration. ClinicalTrials.gov identifier: NCT00436007. GlaxoSmithKline study ID number: 106369 (Malaria-050

Cyclodipeptide synthases, a family of class-I aminoacyl-tRNA synthetase-like enzymes involved in non-ribosomal peptide synthesis

Cyclodipeptide synthases (CDPSs) belong to a newly defined family of enzymes that use aminoacyl-tRNAs (aa-tRNAs) as substrates to synthesize the two peptide bonds of various cyclodipeptides, which are the precursors of many natural products with noteworthy biological activities. Here, we describe the crystal structure of AlbC, a CDPS from Streptomyces noursei. The AlbC structure consists of a monomer containing a Rossmann-fold domain. Strikingly, it is highly similar to the catalytic domain of class-I aminoacyl-tRNA synthetases (aaRSs), especially class-Ic TyrRSs and TrpRSs. AlbC contains a deep pocket, highly conserved among CDPSs. Site-directed mutagenesis studies indicate that this pocket accommodates the aminoacyl moiety of the aa-tRNA substrate in a way similar to that used by TyrRSs to recognize their tyrosine substrates. These studies also suggest that the tRNA moiety of the aa-tRNA interacts with AlbC via at least one patch of basic residues, which is conserved among CDPSs but not present in class-Ic aaRSs. AlbC catalyses its two-substrate reaction via a ping-pong mechanism with a covalent intermediate in which l-Phe is shown to be transferred from Phe-tRNAPhe to an active serine. These findings provide insight into the molecular bases of the interactions between CDPSs and their aa-tRNAs substrates, and the catalytic mechanism used by CDPSs to achieve the non-ribosomal synthesis of cyclodipeptides

Necrotizing enterocolitis following the surgical repair of a left congenital diaphragmatic hernia

Necrotizing enterocolitis (NEC) is an important cause of mortality and morbidity in neonatal intensive care units. It often occurs in preterms with a low birth weight, associating infectious and vascular phenomena in a context of immune system immaturity. This leads to the alteration of the intestinal wall and potentially lethal complications, requiring medical support and surgical management. In full term infants, NEC is less common and an infectious hypothesis is usually suspected given the epidemic distribution of cases. Here, we report on a rare case of NEC following the surgical repair of a congenital diaphragmatic hernia