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Haloferax sp. D1227, isolated from soil contaminated with highly saline oil brine, is the first halophilic archaeon to demonstrate the utilization of aromatic compounds (i.e., benzoic acid, cinnamic acid, and 3-phenylpropionic acid) as sole carbon and energy sources for growth. The degradation of 3-phenylpropionic acid in this strain was studied to examine the strategies utilized by Archaea to metabolize aromatic compounds. Based on our findings of (1) the extracellular accumulation of cinnamic acid, benzoic acid, 3-hydroxybenzoic acid, and gentisic acid in cultures of Haloferax D 1227 grown on 3-phenylpropionic acid, (2) the presence of an 3-phenylpropionylCoA dehydrogenase, (3) the ATP, CoA, and NAD-dependent conversion of cinnamic acid to benzoylCoA, and (4) the presence of gentisate 1,2-dioxygenase, we propose that Haloferax D1227 metabolizes 3-phenylpropionic acid by initial 2-carbon shortening of the side chain to benzoylCoA via a mechanism similar to fatty acid beta-oxidation, followed by aromatic degradation using a gentisate pathway. The upper aliphatic pathway from 3-phenylpropionic acid to benzoic acid is regulated separately from the lower gentisate pathway.

An aerobic thermophile has been isolated from an α-pinene enrichment culture. The isolate, which was designated BR425, has been tentatively identified as Bacillus pallidus using 16S ribosomal RNA gene sequencing and organism morphology. Monophasic and biphasic incubations of BR425 cells with α-pinene, β-pinene, and limonene yielded a number of oxidized monoterpene metabolites with carveol as a common metabolite. A pinene degradation pathway with carveol and carvone as central metabolic intermediates is suggested.

The aims of this study were to investigate the functions of muscle torque and its relation to other torque components during sprinting stance and swing phases. Three-dimensional kinematics and ground reaction force data were collected from eight elite male sprinters performing maximal-effort sprinting on a synthetic track. Intersegmental dynamics approach (ISD) was used to quantify lower extremity joint torque and their components during one gait cycle of the maximal speed phase during sprinting. Specifically, a modified version of the ISD was used to determine the relationship among the active muscle torque (MST), passive motion-dependent torque (MDT), ground reaction torque (EXT), gravitational torque (GTT), and net joint torque (NET) during stance and swing phases. The contribution of each torque component to lower extremity joint motion was quantified. Our results revealed that the active MST functioned to counteract EXT during stance phase. EXT acted to accelerate knee extension and hip flexion, meanwhile the muscles across these joints produced flexion torque at the knee and extension torque at the hip. During swing phase, MDT at the knee and hip joints was mainly produced by leg angular acceleration which was very significant at the moment when leg swing from forward to backward, active MST counterbalanced the effect of MDT. In summary, muscle torque functions mainly to push the ground to counter ground reaction force for controlling the movement during stance phase. However, the role of muscle torque changes during swing phase to mainly counteract the effect of MDT to control the movement direction of the lower extremity at both the hip and knee joints.

The utilization of sport-related compression garments has attracted a great deal of attention from among Sports Science scholars. The function of the garments, such as to maintain muscle functions, reduce sports injuries and improve athletic performance, has been an issue of debate since the beginning of the new century. In this study, a number of methods including a literature review, logical analysis and mathematical statistics, are used to analyse earlier compression garments research, which can be found by searching hardcopy journals and online databases. Among the existing studies, most have tested and confirmed the functions of the garments; however, only a few have mentioned the underlying mechanism. Thus, by using more advanced and appropriate compression materials, future studies into compression garments will be focused on the vibration characteristics of muscles (soft tissues), and especially on their proprioceptive sensation, neuromuscular control, injury prevention and performance enhancement.

The purpose of this study was to explore the footwear effects on impact forces and soft-tissue vibrations during landing. 12 male basketball players were instructed to perform drop jumps and unanticipated drop landings from 30 cm, 45 cm, and 60 cm heights in basketball shoes (BS) and control shoes (CS). 3D kinematics, ground reaction force (GRF), and soft-tissue vibrations of the leg, and acceleration of the shoe heel counter were measured simultaneously. The results showed no significant shoe effect on the characteristics of the impact force nor on the resonance frequency and peak transmissibility of soft-tissue vibrations during the impact phase of the drop jump. For the unanticipated drop landings, however, the magnitude of both peak GRF and peak loading rate were significantly lower with BS compared to CS across all 3 heights ( p 0.05); meanwhile BS showed a significant decrease in GRF frequency compared to CS at 45 cm ( p 0.05) and 60 cm ( p 0.01) heights. Furthermore, the peak transmissibility in BS was significantly lower than that in CS for both the quadriceps and hamstrings during the 60 cm unanticipated drop landing ( p 0.05). These findings provide p reliminary evidence suggesting that if the neuromuscular system fails to prepare properly for an impact during landing, a shoe intervention may be an effective method for minimizing impact force and reducing soft tissue resonance.

To introduce the concept and clinical applications of rotational alignment of the femoral prosthesis in total knee arthroplasty (TKA) so as to avoided the postoperative complications caused by rotational alignment.The clinical and experimental research literature about rotational alignment of the femoral prosthesis in TKA was extensively reviewed and analyzed.Femoral prosthesis malrotation can lead to flexion gap unbalanced and undesirable patellar track. Rotation alignment of the femoral prosthesis is defined with radiological and computer assisted technique at pre- and post-operation, which can make the rotation alignment of the femoral prosthesis and the function of the knee favorable.In recent years, many surgical skills and new techniques of defining the rotational alignment are developed, and good clinical results are achieved.

The purpose of this study was to explore the effect of three common sports surfaces on plantar pressure characteristics and performance of impact in lower extremity during jogging. Methods: Medilogic insole plantar pressure system® was utilized to collect plantar pressure data (including contact time, peak pressure, pressure-time integral) and pressure distribution during touch-down and toe-off phases. Grass surface, rubber running track, and concrete surface were chosen as testing surfaces. Results: During touchdown, the first peak pressure (time) and pressure-time integral within first peak period of running on the concrete were significantly greater (or earlier) than the other two. However, the pressure distribution of all insole areas (forefoot, mid-foot, heel, lateral, and medial) were similar among the three types of sports surfaces both in touch-down and toe-off. Conclusion: Surfaces with less or no cushioning would lead to a higher risk of sports injury during long-term jogging. However, the further effect of different surfaces on pressure distribution and the influence it may bring subsequently was not as distinct as expected.

The utilization of sports compression equipments has widely attracted the attention of researchers with the need to maintain muscle functions, reduce sport injuries, and improve athletic performance. It has become a heated issue in research field of sportswear since the beginning of the new century. Methods of literature review, logic analysis and mathematical statistics were used to analyze the study of compression garments from hardcopy journals and online databases. Although a series of studies showed the benefits of compression garments, however, the underlying mechanisms have not been confirmed yet. Moreover, no research referring compression equipments have been conducted in China, which also restricts our native people from getting a further understanding about the potential mechanism of compression apparel. Based on more advanced compression materials, the future study of compression garments will focus on the vibration characteristics of muscle (soft tissue), especially on proprioceptive sensation, neuromuscular control, injury prevention, and performance enhancement.

The aim of this study was to explore the effect of basketball shoes on impact forces, soft tissue vibrations, and their possible interactions during active landing (drop jump, DJ) and passive landing (PL). Six male basketball players wore two types of shoes (basketball shoe vs. control shoe) to execute 5 trials of double-leg landing in each of 6 testing conditions from a manual tiltable platform (i.e., 2 landing styles × 3 heights: 30 cm, 45 cm, and 60 cm). Kinematics of the lower extremity, ground reaction force data, and accelerations of the quadriceps femoris were collected simultaneously. The results showed that there was no significant shoe effect on the input signal for both the time domain and the frequency domain during DJ. However, during PL, the amplitude of impact and loading rate in basketball shoe were obviously smaller at each height (p

Gentisate 1,2-dioxygenase from the extreme halophile Haloferax sp. D1227 (Hf. D1227) was purified using a three-step procedure. The enzyme was found to be a homotetramer of 42,000 +/- 1,000 Da subunits, with a native molecular weight of 174,000 +/- 6,000 Da. The optimal salt concentration, temperature, and pH for enzyme activity were 2 M KCl or NaCl, 45 degrees C, and pH 7.2, respectively. The gene encoding Hf. D1227 gentisate 1,2-dioxygenase was cloned, sequenced, and expressed in Haloferax volcanii. The deduced amino acid sequence exhibited a 9.2% excess acidic over basic amino acids typical of halophilic enzymes. Four novel histidine clusters and a possible extradiol dioxygenase fingerprint region were identified.

Background There is still uncertainty concerning the beneficial effects of shoe collar height for ankle sprain prevention and very few data are available in the literature regarding the effect of high-top and low-top shoes on muscle responses during landing. The purpose of this study was to quantify the effect of high-top and low-top shoes on ankle inversion kinematics and pre-landing EMG activation of ankle evertor muscles during landing on a tilted surface. Methods Thirteen physical education students landed on four types of surfaces wearing either high-top shoes (HS) or low-top shoes (LS). The four conditions were 15° inversion, 30° inversion, combined 25° inversion + 10° plantar flexion, and combined 25° inversion + 20° plantar flexion. Ankle inversion kinematics and EMG data of the tibialis anterior (TA), peroneus longus (PL), and peroneus brevis (PB) muscles were measured simultaneously. A 2 × 4 (shoe × surface) repeated measures ANOVA was performed to examine the effect of shoe and landing surfaces on ankle inversion and EMG responses. Results No significant differences were observed between the various types of shoes in the maximum ankle inversion angle, the ankle inversion range of motion, and the maximum ankle inversion angular velocity after foot contact for all conditions. However, the onset time of TA and PB muscles was significantly later wearing HS compared to LS for the 15° inversion condition. Meanwhile, the mean amplitude of the integrated EMG from the 50 ms prior to contact (aEMGpre) of TA was significantly lower with HS compared to LS for the 15° inversion condition and the combined 25° inversion + 20° plantarflexion condition. Similarly, the aEMGpre when wearing HS compared to LS also showed a 37.2% decrease in PL and a 31.0% decrease in PB for the combined 25° inversion + 20° plantarflexion condition and the 15° inversion condition, respectively. Conclusion These findings provide preliminary evidence suggesting that wearing high-top shoes can, in certain conditions, induce a delayed pre-activation timing and decreased amplitude of evertor muscle activity, and may therefore have a detrimental effect on establishing and maintaining functional ankle joint stability.