Simultaneous removal of NOX and SO2 from flue gas in an integrated FGD-CABR system by sulfur cycling-mediated Fe(II)EDTA regeneration.

Chemical absorption-biological reduction (CABR) process is an attractive method for NOX removal and Fe(II)EDTA regeneration is important to sustain high NOX removal. In this study a sustainable and eco-friendly sulfur cycling-mediated Fe(II)EDTA regeneration method was incorporated in the integrated biological flue gas desulfurization (FGD)-CABR system. Here, we investigated the NOX and SO2 removal efficiency of the system under three different flue gas flows (100 mL/min, 500 mL/min, and 1000 mL/min) and evaluated the feasibility of chemical Fe(III)EDTA reduction by sulfide in series of batch tests. Our results showed that complete SO2 removal was achieved at all the tested scenarios with sulfide, thiosulfate and S0 accumulation in the solution. Meanwhile, the total removal efficiency of NOX achieved ∼100% in the system, of which 3.2%-23.3% was removed in spray scrubber and 76.7%-96.5% in EGSB reactor along with no N2O emission. The optimal pH and S2-/Fe(III)EDTA for Fe(II)EDTA regeneration and S0 recovery was 8.0 and 1:2. The microbial community analysis results showed that the cooperation of heterotrophic denitrifier (Saprospiraceae_uncultured and Dechloromonas) and iron-reducing bacteria (Klebsiella and Petrimonas) in EGSB reactor and sulfide-oxidizing, nitrate-reducing bacteria (Azoarcus and Pseudarcobacter) in spray scrubber contributed to the efficient removal of NOX in flue gas.

Characterizing the Effects of Explosive Ordnance Disposal Operations on the Human Body While Wearing Heavy Personal Protective Equipment.

OBJECTIVE: To provide a comprehensive characterization of explosive ordnance disposal (EOD) personal protective equipment (PPE) by evaluating its effects on the human body, specifically the poses, tasks, and conditions under which EOD operations are performed. BACKGROUND: EOD PPE is designed to protect technicians from a blast. The required features of protection make EOD PPE heavy, bulky, poorly ventilated, and difficult to maneuver in. It is not clear how the EOD PPE wearer physiologically adapts to maintain physical and cognitive performance during EOD operations. METHOD: Fourteen participants performed EOD operations including mobility and inspection tasks with and without EOD PPE. Physiological measurement and kinematic data recording were used to record human physiological responses and performance. RESULTS: All physiological measures were significantly higher during the mobility and the inspection tasks when EOD PPE was worn. Participants spent significantly more time to complete the mobility tasks, whereas mixed results were found in the inspection tasks. Higher back muscle activations were seen in participants who performed object manipulation while wearing EOD PPE. CONCLUSION: EOD operations while wearing EOD PPE pose significant physical stress on the human body. The wearer's mobility is impacted by EOD PPE, resulting in decreased speed and higher muscle activations. APPLICATION: The testing and evaluation methodology in this study can be used to benchmark future EOD PPE designs. Identifying hazards posed by EOD PPE lays the groundwork for developing mitigation plans, such as exoskeletons, to reduce physical and cognitive stress caused by EOD PPE on the wearers without compromising their operational performance.

Neural and non-neural contributions to ankle spasticity in children with cerebral palsy.

AIM: To assess the neural and non-neural contributions to spasticity in the impaired ankle of children with cerebral palsy (CP). METHOD: Instrumented tapping of the Achilles tendon was done isometrically to minimize non-neural contributions and elicit neural contributions. Robot-controlled ankle stretching was done at various velocities, including slow stretching, with minimized neural contributions. Spasticity was assessed as having neural (phasic and tonic stretch reflex torque, tendon reflex gain, contraction rate, and half relaxation rate) and non-neural origin (elastic stiffness and viscous damping) in 17 children with CP (six females and 11 males; mean age [SD] 10y 8mo [3y 11mo], range 4y-18y) and 17 typically developing children (six females and 11 males; mean age [SD] 12y 7mo [2y 9mo], range 7y-18y). All torques were normalized to weight×height. RESULTS: Children with CP showed increased phasic and tonic stretch reflex torque (p=0.004 and p=0.001 respectively), tendon reflex gain (p=0.02), contraction rate (p=0.038), half relaxation rate (p=0.02), elastic stiffness (p=0.01), and viscous damping (p=0.01) compared to typically developing children. INTERPRETATION: Controlled stretching and instrumented tendon tapping allow the systematic quantification of various neural and non-neural changes in CP, which can be used to guide impairment-specific treatment. WHAT THIS PAPER ADDS: Ankle spasticity is associated with increased phasic and tonic stretch reflexes, tendon reflex gain, and contraction and half relaxation rates. Ankle spasticity is also associated with increased elastic stiffness and viscous damping.

Contribuciones neuronales y no neuronales a la espasticidad del tobillo en niños con parálisis cerebral OBJETIVO: Evaluar las contribuciones neurales y no neurales a la espasticidad en el tobillo comprometido de niños con parálisis cerebral (PC). MÉTODO: La percusión instrumentada en el tendón de Aquiles se realizó de forma isométrica para minimizar las contribuciones no neurales y un tirón del tendón exagerado, para obtener contribuciones neurales. El estiramiento del tobillo controlado por robot se realizó a varias velocidades, incluido el estiramiento lento, con contribuciones neurales minimizadas. Se evaluó la espasticidad como neural (torque reflejo de estiramiento fásico y tónico, ganancia del reflejo tendinoso, tasa de contracción y media tasa de relajación) y origen no neural (rigidez elástica y amortiguación viscosa) en 17 niños con PC (seis mujeres y 11 varones; edad media [DE] 10a 8m [3a 11m], rango 4a-18a) y 17 niños con desarrollo típico (seis mujeres y 11 hombres; edad media [SD] 12a 7m [2a 9m], rango 7a-18a). Todos los pares de torsion se normalizaron al peso × altura. RESULTADOS: Los niños con PC mostraron un aumento del torque reflejo de estiramiento fásico y tónico (p = 0,004 y p = 0,001 respectivamente), ganancia refleja del tendón (p = 0,02), tasa de contracción (p = 0,038), tasa de relajación media (p = 0,02), rigidez elastica (p = 0,01) y amortiguación viscosa (p = 0,01) en comparación con los niños con desarrollo normal. INTERPRETACIÓN: El estiramiento controlado y la percusión instrumentada del tendón, permiten la cuantificación sistemática de varios cambios neuronales y no neuronales en la PC, que pueden usarse para guiar el tratamiento específico de la discapacidad.

Contribuições neurais e não neurais para a espasticidade do tornozelo em crianças com paralisia cerebral OBJETIVO: Avaliar as contribuições neurais e não-neurais para a espasticidade no tornozelo comprometido de crianças com paralisia cerebral (PC). MÉTODO: O golpeamento instrumentalizado do tendão de Aquiles foi realizado isometricamente para minimizar as contribuições não-neurais e um desvio exagerado do tendão, e assim eliciar as contribuições neurais. O alongamento do tornozelo controlado por um robô foi realizado em várias velocidades, incluindo alongamento lento, com contribuições neurais limitadas. A espasticidade foi avaliada como tendo origem neural (torque do reflexo fásico e tônico, ganho do reflexo tendinoso, taxa de contração, e taxa de meio relaxamento) e não-neural (rigidez elástica e amortecimento viscoso) em 17 crianças com PC (seis do sexo feminino e 11 do sexo masculino; média de idade [DP] 10a 8m [3 11m], variação 4a-18a) e 17 crianças com desenvolvimento típico (seis do sexo feminino e 11 do sexo masculino; média de idade [DP] 12a 7m [2a 9m], variação 7a-18a). Todos os torques foram normalizados para peso x altura. RESULTADOS: Crianças com PC mostraram aumento do torque do reflexo tônico e fásico e (p=0,004 e p=0,001 respectivamente), ganho do reflexo tendinoso (p=0,02), taxa de contração (p=0,038), taxa de meio relaxamento (p=0,02), rigidez elástica (p=0,01), e amortecimento viscoso (p=0,01) em comparação com as crianças com desenvolvimento típico. INTERPRETAÇÃO: O alongamento controlado e o golpeamento instrumentalizado do tendão permitem quantificação sistemática de várias mudanças neurais e não-neurais em PC, as quais podem ser usadas para guiar tratamento específico para a deficiência observada.

Muscle activation pattern during self-propelled treadmill walking.

[Purpose] To examine muscular demands during self-propelled treadmill walking to provide a potential option for fitness training. [Participants and Methods] Eleven healthy college students were recruited. Participants walked under three conditions: over-ground walking at a self-selected speed, treadmill walking at a self-selected speed, and treadmill walking at a speed comparable to that of over-ground walking. Step lengths and lower extremity muscle activations were recorded while participants walked under the three conditions. [Results] Step lengths were significantly shorter when participants walked on a self-propelled treadmill than when walking over-ground. The spatiotemporal and muscle activations of the gaits varied among the different walking conditions. Muscular demands at the moment of heel-strike were higher around the hip and knee when walking on the self-propelled treadmill than when walking over-ground. [Conclusion] During heel-strike, the lower extremity extensors were activated more on the self-propelled treadmill with an incline, especially at faster speeds, than during over-ground walking. A low-cost, self-propelled treadmill may be a modality for training specific muscles.

Home-Based Versus Laboratory-Based Robotic Ankle Training for Children With Cerebral Palsy: A Pilot Randomized Comparative Trial.

OBJECTIVE: To examine the outcomes of home-based robot-guided therapy and compare it to laboratory-based robot-guided therapy for the treatment of impaired ankles in children with cerebral palsy. DESIGN: A randomized comparative trial design comparing a home-based training group and a laboratory-based training group. SETTING: Home versus laboratory within a research hospital. PARTICIPANTS: Children (N=41) with cerebral palsy who were at Gross Motor Function Classification System level I, II, or III were randomly assigned to 2 groups. Children in home-based and laboratory-based groups were 8.7±2.8 (n=23) and 10.7±6.0 (n=18) years old, respectively. INTERVENTIONS: Six-week combined passive stretching and active movement intervention of impaired ankle in a laboratory or home environment using a portable rehabilitation robot. MAIN OUTCOME MEASURES: Active dorsiflexion range of motion (as the primary outcome), mobility (6-minute walk test and timed Up and Go test), balance (Pediatric Balance Scale), Selective Motor Control Assessment of the Lower Extremity, Modified Ashworth Scale (MAS) for spasticity, passive range of motion (PROM), strength, and joint stiffness. RESULTS: Significant improvements were found for the home-based group in all biomechanical outcome measures except for PROM and all clinical outcome measures except the MAS. The laboratory-based group also showed significant improvements in all the biomechanical outcome measures and all clinical outcome measures except the MAS. There were no significant differences in the outcome measures between the 2 groups. CONCLUSIONS: These findings suggest that the translation of repetitive, goal-directed, biofeedback training through motivating games from the laboratory to the home environment is feasible. The benefits of home-based robot-guided therapy were similar to those of laboratory-based robot-guided therapy.

Changes of general fitness and muscle properties following police cadet training.

[Purpose] This study was performed to examine the relationship between physical performance and muscle properties during police cadet training. The study's hypothesis was that improved physical performance brought about by training, would in turn cause a reduction in muscle flexibility. [Subjects and Methods] Fifty-nine police cadets were included in this study. Standard fitness tests and quantitative assessments of muscular biomechanical properties were conducted before, during and after the 20-week cadet training. [Results] General fitness had improved at the end of the police cadet training. There was no significant decrease in muscle flexibility as measured by the Sit-and-Reach test. However, muscle compliance of the non-dominant leg measured by the relaxation coefficient had decreased at the end of the police cadet training. [Conclusion] The increased sit-and-reach distance could be due in part to strengthening of the abdominal muscles. On the other hand, the biomechanical test, which was specific to muscle extensibility, showed a reduction in the relaxation coefficient of the non-dominant leg. Our data suggests that changes in muscle compliance as a result of lower extremity training should be considered. This data may be useful in the design of a training protocol that prevents the potential injuries caused by reduced muscle flexibility.

The neuromuscular control for lower limb exoskeleton- a 50-year perspective.

Historically, impaired lower limb function has resulted in heavy health burden and large economic loss in society. Although experts from various fields have put large amounts of effort into overcoming this challenge, there is still not a single standard treatment that can completely restore the lost limb function. During the past half century, with the advancing understanding of human biomechanics and engineering technologies, exoskeletons have achieved certain degrees of success in assisting and rehabilitating patients with loss of limb function, and therefore has been spotlighted in both the medical and engineering fields. In this article, we review the development milestones of lower limb exoskeletons as well as the neuromuscular interactions between the device and wearer throughout the past 50 years. Fifty years ago, the lower-limb exoskeletons just started to be devised. We review several prototypes and present their designs in terms of structure, sensor and control systems. Subsequently, we introduce the development milestones of modern lower limb exoskeletons and discuss the pros and cons of these differentiated devices. In addition, we summarize current important neuromuscular control systems and sensors; and discuss current evidence demonstrating how the exoskeletons may affect neuromuscular control of wearers. In conclusion, based on our review, we point out the possible future direction of combining multiple current technologies to build lower limb exoskeletons that can serve multiple aims.

Near-term fetal hypoxia-ischemia in rabbits: MRI can predict muscle tone abnormalities and deep brain injury.

BACKGROUND AND PURPOSE: The pattern of antenatal brain injury varies with gestational age at the time of insult. Deep brain nuclei are often injured at older gestational ages. Having previously shown postnatal hypertonia after preterm fetal rabbit hypoxia-ischemia, the objective of this study was to investigate the causal relationship between the dynamic regional pattern of brain injury on MRI and the evolution of muscle tone in the near-term rabbit fetus. METHODS: Serial MRI was performed on New Zealand white rabbit fetuses to determine equipotency of fetal hypoxia-ischemia during uterine ischemia comparing 29 days gestation (E29, 92% gestation) with E22 and E25. E29 postnatal kits at 4, 24, and 72 hours after hypoxia-ischemia underwent T2- and diffusion-weighted imaging. Quantitative assessments of tone were made serially using a torque apparatus in addition to clinical assessments. RESULTS: Based on the brain apparent diffusion coefficient, 32 minutes of uterine ischemia was selected for E29 fetuses. At E30, 58% of the survivors manifested hind limb hypotonia. By E32, 71% of the hypotonic kits developed dystonic hypertonia. Marked and persistent apparent diffusion coefficient reduction in the basal ganglia, thalamus, and brain stem was predictive of these motor deficits. CONCLUSIONS: MRI observation of deep brain injury 6 to 24 hours after near-term hypoxia-ischemia predicts dystonic hypertonia postnatally. Torque-displacement measurements indicate that motor deficits in rabbits progressed from initial hypotonia to hypertonia, similar to human cerebral palsy, but in a compressed timeframe. The presence of deep brain injury and quantitative shift from hypo- to hypertonia may identify patients at risk for developing cerebral palsy.

Alterations in motor modules and their contribution to limitations in force control in the upper extremity after stroke.

The generation of isometric force at the hand can be mediated by activating a few motor modules. Stroke induces alterations in motor modules underlying steady-state isometric force generation in the human upper extremity (UE). However, how the altered motor modules impact task performance (force production) remains unclear as stroke survivors develop and converge to the three-dimensional (3D) target force. Thus, we tested whether stroke-specific motor modules would be activated from the onset of force generation and also examined how alterations in motor modules would induce changes in force representation. During 3D isometric force development, electromyographic (EMG) signals were recorded from eight major elbow and shoulder muscles in the paretic arm of 10 chronic hemispheric stroke survivors and both arms of six age-matched control participants. A non-negative matrix factorization algorithm identified motor modules in four different time windows: three "exploratory" force ramping phases (Ramps 1-3; 0-33%, 33-67%, and 67-100% of target force magnitude, respectively) and the stable force match phase (Hold). Motor module similarity and between-force coupling were examined by calculating the scalar product and Pearson correlation across the phases. To investigate the association between the end-point force representation and the activation of the motor modules, principal component analysis (PCA) and multivariate multiple linear regression analyses were applied. In addition, the force components regressed on the activation profiles of motor modules were utilized to model the feasible force direction. Both stroke and control groups developed exploratory isometric forces with a non-linear relationship between EMG and force. During the force matching, only the stroke group showed abnormal between-force coupling in medial-lateral and backward-forward and medial-lateral and downward-upward directions. In each group, the same motor modules, including the abnormal deltoid module in stroke survivors, were expressed from the beginning of force development instead of emerging during the force exploration. The PCA and the multivariate multiple linear regression analyses showed that alterations in motor modules were associated with abnormal between-force coupling and limited feasible force direction after stroke. Overall, these results suggest that alterations in intermuscular coordination contribute to the abnormal end-point force control under isometric conditions in the UE after stroke.

MAL31, a sugar transporter involved in pullulan biosynthesis in Aureobasidium pullulans.

To investigate the role of the sugar transporter MAL31 on pullulan biosynthesis, the coding gene mal31 was respectively disrupted and overexpressed in the parental strain A. pullulans CCTCC M 2012259 to construct mutants of A. pullulans Δmal31 and A. pullulans Mal31. Batch pullulan production significantly decreased by 69.1 % in A. pullulans Δmal31 but increased by 15.9 % in A. pullulans Mal31, as compared to the parental strain. We performed kinetics analysis, assays of key enzymes, determination of intracellular UDPG, NADH, and ATP contents, and measurement of transcriptional levels of genes associated with pullulan biosynthesis and excretion. The results confirmed that the mal31 disruption decreased the glucose consumption rate, decreased the formation rate and titer of pullulan, but increased the intracellular UDPG supply for ß-glucan accumulation. In contrast, the mal31 overexpression increased the transcriptional levels of genes associated with pullulan biosynthesis, and accelerated the rates of glucose consumption and pullulan formation, thereby increased pullulan production. Our findings revealed that MAL31 is involved in the transport of precursors for pullulan biosynthesis. This study provides an accurate operating site for genetic modification of A. pullulans for improving pullulan production and also presents a feasible technique route for the overproduction of other polysaccharides.

Strain effects of placing an arthroscopic portal through the subscapularis tendon.

HYPOTHESIS: The biomechanical effects of placing a portal through the subscapularis tendon have not been studied. Our hypothesis is that placing a portal through the subscapularis tendon will affect the strain properties of the tendon. MATERIALS AND METHODS: Eight shoulders from deceased donors were dissected to expose the subscapularis musculotendinous unit. The subscapularis muscle was isolated, the arm was locked at neutral (0° abduction, 0° flexion/extension, 0° external rotation/internal rotation), and 3 cables were sutured to the subscapularis musculotendinous junction. Each cable was connected to a static weight. Three differential variable reluctance transducers (DVRTs) from Microstrain were sutured into the subscapularis tendon-superior, inferior, and in line with the proposed 5 o'clock portal. The musculotendinous unit was loaded along its line of action with 3, 9, and then 15 kg. Strain at each DVRT was measured in the native subscapularis tendon at each load level. The same strain measurement was taken after placing and removing a 5-mm suture anchor through the 5 o'clock portal and in the tendon after placing and removing an 8-mm cannula. RESULTS: Penetrating the subscapularis tendon with either a 5-mm suture anchor or an 8-mm cannula does not produce any statistically significant change in strain compared with the native tendon. CONCLUSION: Placing an anchor, or even an 8-mm cannulated portal, does not significantly alter the strain properties of the subscapularis tendon. This lack of effect on the strain characteristics of the subscapularis does not preclude the possibility of clinical effects.

Effects of Interval-Training Exercise on People Who Have Had Persistent Post-Concussive Symptoms for Less Than One Year: A Pilot Study.

This study is to examine the effects of a 12-session moderate intensity-interval-training program with blood flow restriction (BFR) and body cooling (BC) on people who have had persistent post-concussive symptoms (PPCS) for <1 year. A single-blind randomized controlled trial of interval-training exercise with BFR and BC was conducted. Twenty-five adults with PPCS were assigned to the experimental group (n = 14) or the control group (n = 11). Both groups rode a recumbent elliptical machine for 21 min at moderate intensity (65% predicted maximum heart rate) twice a week for 6 weeks, but only the experimental group received BFR and BC while riding. The variances of overall PPCS scale scores and their sub-domain scores for individuals during the 6-week intervention and 6-week follow-up period were calculated. During the intervention, the fluctuation of overall symptom severity, severity in the cognitive domain and severity in the mood domain were significantly less in the experimental group (p = 0.03; p = 0.02; p = 0.02). During the follow-up period, the number of symptoms remained more stable in the experimental group (p = 0.02), and a trend toward less fluctuation of symptom severity (p = 0.05) was also observed. The reduced number of symptoms in the cognitive and sleep domains remained more stable in the experimental group following the intervention (p = 0.007; p = 0.02). The severity of mood and sleep symptoms also remained more stable during the follow-up period in the experimental group (p = 0.04). More stable recovery was found in individuals who exercised using BFR and BC than in those who underwent exercise without BFR and BC. Moderate intensity-interval-training exercise with BFR and BC alleviated post-concussive symptoms in people who have had PPCS <1 year.

Characterization of spasticity in cerebral palsy: dependence of catch angle on velocity.

AIM: To evaluate spasticity under controlled velocities and torques in children with cerebral palsy (CP) using a manual spasticity evaluator. METHOD: The study involved 10 children with spastic CP (six males, four females; mean age 10 y 1 mo, SD 2 y 9 mo, range 7-16 y; one with quadriplegia, six with right hemiplegia, three with left hemiplegia; Gross Motor Function Classification System levels I [n=2], II [n=3], III [n=2], IV [n=2], and V [n=1]; Manual Ability Classification System levels II [n=5], III [n=4], and V [n=1]) and 10 typically developing participants (four males, six females; mean age 10 y 3 mo, SD 2 y 7 mo, range 7-15 y). Spasticity and catch angle were evaluated using joint position, resistance torque, and torque rate at velocities of 90 degrees, 180 degrees, and 270 degrees per second, controlled using real-time audio-visual feedback. Biomechanically, elbow range of motion (ROM), stiffness, and energy loss were determined during slow movement (30 degrees/s) and under controlled terminal torque. RESULTS: Compared with typically developing children, children with CP showed higher reflex-mediated torque (p<0.001) and the torque increased more rapidly with increasing velocity (p<0.001). Catch angle was dependent on velocity and occurred later with increasing velocity (p=0.005). Children with CP showed smaller ROM (p<0.05), greater stiffness (p<0.001), and more energy loss (p=0.003). INTERPRETATION: Spasticity with velocity dependence may also be position-dependent. The delayed catch angle at higher velocities indicates that the greater resistance felt by the examiner at higher velocities was also due to position change, because the joint was moved further to a stiffer position at higher velocities.

Serum miR-1290 and miR-1246 as Potential Diagnostic Biomarkers of Human Pancreatic Cancer.

Background: Pancreatic cancer (PC) is a highly malignant tumor with no effective early diagnostic biomarkers. This study was performed to screen and identify serum microRNAs (miRNAs) as noninvasive biomarkers for PC diagnosis. Methods: Two upregulated miRNAs were selected by integrated analysis of three independent GEO datasets. Then, the expressions of two miRNAs in serum were determined by quantitative reverse-transcription PCR among 120 PC patients, 40 benign disease controls and 40 healthy controls. The correlation between serum miRNAs and clinical characteristics was analyzed. The diagnostic utility of miRNAs was compared to CA19-9 using receiver operating characteristic curve analysis. Results: We discovered miR-1290 and miR-1246 were upregulated in PC patients through GEO datasets analysis. Serum miR-1290 and miR-1246 expression levels were elevated in PC patients compared to all controls and dramatically decreased after tumor resection (all P<0.001). The area under the curve (AUC) for miR-1290 was larger than miR-1246 and CA19-9 (miR-1290: 0.91; miR-1246: 0.81; CA19-9: 0.82). The combined diagnosis of individual or both miRNAs with CA19-9 was more effective for discriminating PC from all controls than the single CA19-9 assay (miR-1290+CA19-9: 0.96, miR-1246+CA19-9: 0.93, miR-1290+miR-1246+CA19-9: 0.97). The abundance of serum miR-1290 and miR-1246 was associated with tumor stage and size respectively and logistic modeling proved that both of them were independent risk factors for PC. Conclusion: Serum miR-1290 and miR-1246 might be promising biomarkers for PC diagnosis and the combined detection of CA19-9, together with miR-1290 or miR-1246, could improve the diagnostic accuracy of PC.

Changes in Muscle Stress and Sarcomere Adaptation in Mice Following Ischemic Stroke.

While abnormal muscle tone has been observed in people with stroke, how these changes in muscle tension affect sarcomere morphology remains unclear. The purpose of this study was to examine time-course changes in passive muscle fiber tension and sarcomeric adaptation to these changes post-ischemic stroke in a mouse model by using a novel in-vivo force microscope. Twenty-one mice were evenly divided into three groups based on the time point of testing: 3 days (D3), 10 days (D10), and 20 days (D20) following right middle cerebral artery ligation. At each testing time, the muscle length, width, and estimated volume of the isolated soleus muscle were recorded, subsequently followed by in-vivo muscle tension and sarcomere length measurement. The mass of the soleus muscle was measured at the end of testing to calculate muscle density. Two-way ANOVA with repeated measures was used to examine the differences in each of the dependent variable among the three time-point groups and between the two legs. The passive muscle stress of the impaired limbs in the D3 group (27.65 ± 8.37 kPa) was significantly lower than the less involved limbs (42.03 ± 18.61 kPa; p = 0.05) and the impaired limbs of the D10 (48.92 ± 14.73; p = 0.03) and D20 (53.28 ± 20.54 kPa; p = 0.01) groups. The soleus muscle density of the impaired limbs in the D3 group (0.69 ± 0.12 g/cm3) was significantly lower than the less involved limbs (0.80 ± 0.09 g/cm3; p = 0.04) and the impaired limbs of the D10 (0.87 ± 0.12 g/cm3; p = 0.02) and D20 (1.00 ± 0.14 g/cm3; p < 0.01) groups. The D3 group had a shorter sarcomere length (2.55 ± 0.26 µm) than the D10 (2.83 ± 0.20 µm; p = 0.03) and D20 group (2.81 ± 0.15 µm; p = 0.04). These results suggest that, while ischemic stroke may cause considerable changes in muscle tension and stress, sarcomere additions under increased mechanical loadings may be absent or disrupted post-stroke, which may contribute to muscle spasticity and/or joint contracture commonly observed in patients following stroke.

Lycium barbarum polysaccharides protects retinal ganglion cells against oxidative stress injury.

The accumulation of excessive reactive oxygen species can exacerbate any injury of retinal tissue because free radicals can trigger lipid peroxidation, protein damage and DNA fragmentation. Increased oxidative stress is associated with the common pathological process of many eye diseases, such as glaucoma, diabetic retinopathy and ischemic optic neuropathy. Many studies have demonstrated that Lycium barbarum polysaccharides (LBP) protects against oxidative injury in numerous cells and tissues. For the model of hypoxia we used cultured retinal ganglion cells and induced hypoxia by incubating with 200 µM cobalt chloride (CoCl2) for 24 hours. To investigate the protective effect of LBP and its mechanism of action against oxidative stress injury, the retinal tissue was pretreated with 0.5 mg/mL LBP for 24 hours. The results of flow cytometric analysis showed LBP could effectively reduce the CoCl2-induced retinal ganglion cell apoptosis, inhibited the generation of reactive oxygen species and the reduction of mitochondrial membrane potential. These findings suggested that LBP could protect retinal ganglion cells from CoCl2-induced apoptosis by reducing mitochondrial membrane potential and reactive oxygen species.

Ultrasonic evaluations of Achilles tendon mechanical properties poststroke.

Spasticity, contracture, and muscle weakness are commonly observed poststroke in muscles crossing the ankle. However, it is not clear how biomechanical properties of the Achilles tendon change poststroke, which may affect functions of the impaired muscles directly. Biomechanical properties of the Achilles tendon, including the length and cross-sectional area, in the impaired and unimpaired sides of 10 hemiparetic stroke survivors were evaluated using ultrasonography. Elongation of the Achilles tendon during controlled isometric ramp-and-hold and ramping up then down contractions was determined using a block-matching method. Biomechanical changes in stiffness, Young's modulus, and hysteresis of the Achilles tendon poststroke were investigated by comparing the impaired and unimpaired sides of the 10 patients. The impaired side showed increased tendon length (6%; P = 0.04), decreased stiffness (43%; P < 0.001), decreased Young's modulus (38%; P = 0.005), and increased mechanical hysteresis (1.9 times higher; P < 0.001) compared with the unimpaired side, suggesting Achilles tendon adaptations to muscle spasticity, contracture, and/or disuse poststroke. In vivo quantitative characterizations of the tendon biomechanical properties may help us better understand changes of the calf muscle-tendon unit as a whole and facilitate development of more effective treatments.

False decrease of high-sensitivity cardiac troponin T assay in pneumatic tube system samples.

BACKGROUND: The pneumatic tube system (PTS) is widely established in clinical laboratories. We aimed to evaluate the impacts of PTS on high-sensitivity cardiac troponin T (hs-cTnT) assays. METHODS: The hemolysis distribution of hs-cTnT PTS specimens from emergency department (ED) were determined by hemolysis index (HI). Grouped samples from 15 healthy volunteers were delivered to the laboratory via manual delivery (MD) or PTS. Interference studies were conducted to access the influence of different hemolysis degrees on hs-cTnT assays. RESULTS: 7.26% PTS specimens from ED were hemolyzed in clinic. Compared with MD samples, we found highly elevated free plasma hemoglobin (Hb) in PTS samples. Hs-cTnT was interfered negatively with free Hb (R = -0.625, P < .001), and it was also validated in interference studies (R ≥ -0.820, all P ≤ .001). Clinically significant bias occurred in each hs-cTnT concentration at 100 mg/dl free Hb (Bias≥ - 13.85%, all P < .05). Moreover, bias of hs-cTnT assays at 50 mg/dl free Hb was approaching 10%, especially at 30 ng/l hs-cTnT concentration (Bias: -11.72%, P < .001). CONCLUSIONS: PTS could increase the frequency of specimen hemolysis which might cause false decrease in hs-cTnT assays. Hence, clinicians should be aware of the increased measurement bias in hs-cTnT from hemolyzed PTS samples with free Hb ≥50 mg/dl.

Occurrence, composition profiles and risk assessment of polycyclic aromatic hydrocarbons in municipal sewage sludge in China.

A nationwide survey, including 75 sludge samples and 18 wastewater samples taken from different wastewater treatment plants (WWTPs) from 23 cities, was carried out to investigate the occurrence and composition profiles of polycyclic aromatic hydrocarbons (PAHs) in China. In total, the concentrations of ∑16PAHs in sludge ranged from 565 to 280,000 ng/g (mean: 9340 ng/g) which was at a moderate level in the world. The composition profiles of PAHs were characterized by 3- and 4-ring PAHs in textile dyeing sludge and 4- and 5-ring PAHs in domestic sludge. Significant variations in regional distribution of PAHs were observed. Both the principal components analysis and diagnostic ratios revealed that vehicle exhaust, coal and natural gas combustion were the main sources of PAHs in China. The estimated concentrations of PAHs were 3820 ng/L and 1120 ng/L in influents and effluents of the WWTPs, respectively. The high toxic equivalent quantity (TEQ) values of PAHs are ascribed to the high PAH levels. Risk quotient values (RQs) in sludge indicated that there was low potential risk to soil ecosystem after sludge had been applied one year except for indeno [1,2,3-cd]pyrene (IcdP) detected in Huaibei, Anhui province.

Time course analysis of the effects of botulinum toxin type a on elbow spasticity based on biomechanic and electromyographic parameters.

OBJECTIVE: To quantify changes of elbow spasticity over time after botulinum toxin type A (BTX-A) injection in the upper extremity of stroke patients. DESIGN: Before-after trial in which the therapeutic effects were followed up at 2, 6, and 9 weeks after the BTX-A injection (Botox). SETTING: Hospital. PARTICIPANTS: Chronic stroke patients (N=8) with upper-limb spasticity. INTERVENTION: BTX-A was injected in upper-limb muscles, including the biceps brachii. MAIN OUTCOME MEASURES: Treatment effects were quantified as the changes in the velocity and the length dependence of hyperexcitable stretch reflexes. Manual sinusoid stretches of the elbow joint at 4 frequencies (1/3, 1/2, 1, 3/2Hz) over a movement range of 60 degrees were performed on patients by using a portable device. The Modified Ashworth Scale (MAS), biomechanic viscosity, and the reflexive electromyography threshold (RET) of the biceps brachii were used to evaluate the degree of hypertonia. RESULTS: The statistical analyses of the MAS score, biomechanic viscosity, and RET revealed a significant decrease in spasticity after the injection (all P<.05). Moreover, our quantitative parameters (biomechanic viscosity, RET) revealed small changes in spasticity after the BTX-A injection that could not be observed from clinical MAS evaluations. Five of 8 subjects showed a maximal reduction in spasticity (in terms of biomechanic viscosity value) within 6 weeks after the injection, whereas it was notable that all subjects exhibited peak RET values at either 2 or 6 weeks after the injection with variable degrees of relapse of spasticity. CONCLUSIONS: Early relapse of spasticity (within 9 weeks of the injection) can be detected from biomechanic and neurophysiologic assessments in a clinical setup. These quantitative indices provide valuable information for clinicians when making decisions to perform additional rehabilitation interventions or another BTX-A injection in the early stages of treatment.