[Predictive value of GRACE discharge score for long-term out-of-hospital death in acute coronary syndrome after percutaneous coronary intervention]

Objective: To evaluate the prognostic value of Global Registry of Acute Coronary Events(GRACE) discharge score for long-term out-of-hospital death in acute coronary syndrome (ACS) after drug-eluting stents (DES) and with Dual-antiplatelet Therapy (DAPT). Methods: Our study was a prospective, observational, single center (Fuwai Hospital of China) study.A total of 6 431consecutive ACS patients underwent percutaneous coronary intervention(PCI)between January 2013 and December 2013 were involved.The primary endpoint was all-cause death and second endpoint was major adverse cardiovascular and cerebrovascular events (MACCE) as a composite of all-cause death, myocardial infarction, revascularization, stent thrombosis or stroke. Results: Finally, 5 867 ACS patients who were received DES with DAPT and had no in-hospital event included in this study, and 59 (1.01%) death and 608 (10.36%) MACCE were reported during 2-year follow-up after discharge.GRACE score was significantly higher among death patients than those survivalpatients (94± 28 vs 78± 24, P<0.001). According to risk stratification of GRACE discharge score, as compared to the low-risk group, death risk in high-risk group was 6.73 times (HR=6.73, 95%CI 3.53-12.84; P<0.001) higher, but could not distinguish between the moderate and low risk group (HR=1.61, 95%CI 0.88-2.95; P=0.124). The GRACE score showed predictive value in ACS patients after DESand with DAPT (area under the receiver operating characteristic curve (AUROC)=0.661; 95%CI 0.586-0.736, P<0.001). In subgroup analysis, GRACE score also showed predictive value both in unstable angina pectoris (UAP)(AUROC=0.660, 95%CI 0.576-0.744; P<0.001) and acute myocardial infarction(AMI)subgroup (AUROC=0.748, 95%CI 0.631-0.864; P=0.001). Conclusion: GRACE discharge score shows prognostic value for long-term out-of-hospital death in ACS patients undergoing PCI with DES and DAPT, and demonstrates good risk stratification of high and low-risk of death.

[Progress in research of vaccination for patients with cancer]

Due to the tumor malignancy or immunosuppressive treatment, patients with cancer in general are more susceptible to vaccine-preventable infections. The types, timing, dose of vaccination or even the immunization program for them may differ from those for the normal persons. At present, it is recommended to use inactivated vaccines for patients with cancer rather than attenuated live vaccines, Vaccinations should be avoided during immunosuppressive therapy; patients with cancer should receive double dosage of hepatitis B vaccines and two doses of inactivated influenza vaccines yearly. This paper summarizes the progress in clinical trials of vaccination for cancer patients in foreign countries, and provide reference for the development and implementation of vaccination strategy for cancer patients in China.

[Relationship of lipid accumulation product with hypertension and diabetes among Beijing residents study]

Objective: To explore the lipid accumulation product (LAP) formula for Beijing adults and to investigate the relationship between lipid accumulation product and hypertension, as well as diabetes. Methods: A cross-sectional study with a representative sample of 19 606 residents in Beijing aged 18-79 years was conducted in 2011. The sex-specific hypothetical minimum waist circumference (WC) was calculated in order to obtain the more applicable LAP formula. Multivariate logistic regression was used to analyze the associations of LAP, combination of LAP and body mass index (BMI) with hypertension and diabetes. Results: The LAP formula for Beijing adults was established as follows: LAP (male)= (WC-61.3) × TG, and LAP (female)= (WC-55.6) × TG. There was an obvious trend of increased risk of hypertension and diabetes with an increment in the tertiles of the LAP both in men and women. The OR (95%CI) for hypertension in the group with highest tertile LAP was 3.62 (3.11-4.22) in men, and 5.79 (4.84-6.93) in women, compared with the lowest tertile group, respectively; and the corresponding OR for diabetes was 3.47 (2.73-4.41) in men, and 4.10 (2.90-5.80) in women, respectively. Compared with the lowest tertile of LAP and normal BMI group, the OR (95%CI) for hypertension in the highest tertile of LAP and obesity group was 6.79 (5.50-8.37) in men, and 9.75 (7.76-12.25) in women, respectively; while the corresponding value for diabetes was 3.97 (2.87-5.49) in men, and 4.13 (2.78-6.14) in women, respectively. Conclusion: The elevated level of LAP was associated with an increased risk of hypertension and diabetes among Beijing adults. LAP could be an important predictor for hypertension and diabetes.

[Meta-analysis on the diagnostic value of laser Doppler imaging for burn depth]

Objective: To evaluate the value of laser Doppler imaging (LDI) in diagnosing deep or superficial partial-thickness burn wound with meta-analysis. Methods: Databases including PubMed, Cochrane Library were searched using key words " burn, burns, burn depth, laser Doppler imaging, laser Doppler perfusion imaging, LDI, LDPI" , and Chinese Journals Full-text Database, Wanfang Database, VIP Database were searched using Chinese key words ",,,," to obtain the published trials of LDI in diagnosing deep or superficial partial-thickness burn wound from the establishment of each database to October 2015. The risk of bias and applicability concerns of the included studies were evaluated by Quality Assessment of Diagnostic Accuracy Studies-2. Data were processed with Meta-DiSc 1.4 statistical software. The heterogeneity among the included studies was evaluated. The pooled estimates of LDI in diagnosing deep or superficial partial-thickness burn wound in the included studies, including sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, as well as the area under the curve of summary receiver operating characteristic and index of Q(*) were calculated. The stability of results of the overall pooled estimates of the included studies was validated by sensitivity analysis. The sources of heterogeneity among the included studies were sought through subgroup analysis. The publication bias caused by the results of the included studies was evaluated by drawing the Deek's funnel plot. Results: A total of 5 articles conforming to the inclusion criteria, involving 138 patients and 179 burn wounds, were included. One of the included studies had low risk of bias, while the other 4 studies had high/unclear risk of bias. In applicability concern aspect, one of the included studies had high/unclear concerns regarding applicability, while the other 4 studies had low concerns regarding applicability. There was no heterogeneity caused by threshold effects among the included studies (no " shoulder arm" plot of the scattered-point distribution was observed in the space of the receiver operating characteristic, β(s)=0.01, P>0.05). There was a high heterogeneity caused by non-threshold effects among the included studies (sensitivity I(2)=54%). The overall pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio of the included studies on LDI in diagnosing deep or superficial partial-thickness burn wound were 95% (with 95% confidence interval 88%-99%), 96% (with 95% confidence interval 90%-99%), 9.75 (with 95% confidence interval 4.35-21.81), 0.11 (with 95% confidence interval 0.05-0.22), and 257.93 (with 95% confidence interval 58.96-1 128.41), respectively. The area under the curve of summary receiver operating characteristic was 0.98, with index of Q(*) 94%. The results of the overall pooled estimates of the included studies was stable. The risk of bias of the selection of the patients, equipment type of LDI, and the selection of diagnostic method in control might be sources of the heterogeneity of the included studies. The Deek's funnel plot indicated that there was no publication bias caused by the results of the included studies (P>0.05). Conclusions: LDI has high sensitivity, specificity, positive likelihood ratio, diagnostic odds ratio and index of Q(*,) large area under the curve of summary receiver operating characteristics, and low negative likelihood ratio in diagnosing deep or superficial partial-thickness burn wound, which has relatively high diagnostic value.

Exogenous substances regulate silkworm fat body protein synthesis through MAPK and PI3K/Akt signaling pathways

Insect fat body is an important intermediate metabolic organ that plays an important role in protein metabolism and detoxification. In order to study the effects of TiO₂ NPs and phoxim on fat body protein synthesis through MAPK and PI3K/Akt signaling pathways in silkworms, we determined the effects of TiO₂ NPs and phoxim, alone and in combination, on fat body protein content of silkworms, analyzed the gene expression profile of the fat body, and verified the expression of characteristic genes. We found that TiO₂ NPs and phoxim alone increased the total protein content of the fat body, and up-regulated MAPK and PI3K/Akt signaling pathway genes. TiO₂ NPs up-regulated the expression of two growth and development-related genes-insulin-like peptide and neuropeptide receptor B-by 5.17 and 3.89-fold, respectively. Phoxim up-regulated the expression of detoxification genes-P450, GST, and CarE2. Pretreatment with TiO₂ NPs could reduce phoxim-increased total protein content and up-regulated MAPK and PI3K/Akt signaling pathway genes and detoxification genes; the activities of detoxification enzymes were consistent with the gene expression pattern. Our results showed that MAPK and PI3K/Akt signaling pathways both regulate fat body protein synthesis in silkworms, but the target proteins induced to express were different under different inducing factors. Our finding may provide a reference for investigating the mechanism of protein synthesis regulation through MAPK and PI3K/Akt signaling pathways.

[Recurrent syncope related to catecholaminergic polymorphic ventricular tachycardia due to de novo RyR2-R2401H mutation]

Objective: To explore the clinical and molecular genetic features of a Chinese patient with catecholaminergic polymorphic ventricular tachycardia (CPVT). Methods: Clinical data including resting electrocardiography, echocardiography and treadmill exercise testing of a patient with CPVT admitted to our department in March 2013 were analyzed, and the peripheral venous blood samples of the patient and his family members and 400 ethnicity-matched healthy controls were obtained. All exons and exon-intron boundaries of the six CPVT-related genes including RYR2, CASQ2, TRDN, CALM1, KCNJ2 and ANKB were sequenced to detect the variants related to CPVT. The relationship between the genotypes and phenotypes was analyzed to direct the target therapy. Results: Recurrent syncope induced either by exercise or extreme frightened fear was observed in this patient. There was no positive family history of syncope or sudden death. The resting electrocardiography and echocardiography of the patient were normal, while the exercise testing revealed bidirectional and polymorphic ventricular tachycardia. A cardiac ryanodine receptor gene mutation (R2401H) was identified in this patient, while this mutation was absent in his parents and sister and 400 controls. No variant was detected in the remaining five candidate genes. Treatment with high dose of metoprolol succinate (118.75 mg/d) was effective and patient was free of syncopal attack during the 2 years follow-up. Conclusion: This is the first report on RyR2-R2401H mutation in Chinese patient with CPVT, and high dose of metoptolol is the effective therapy option for CPVT related to RyR2 mutation.

Effects of high-heeled shoes and asymmetrical load carrying on lower-extremity kinematics during walking in young women

BACKGROUND

Asymmetrical load carrying and wearing high-heeled shoes are very common. Biomechanics studies on the combined effects of high-heeled shoe wearing and asymmetrical load carrying are lacking. We sought to identify changes in lower-extremity joint kinematics associated with the effect of shoes and asymmetrical load carrying during walking.

METHODS

Fifteen healthy young women (mean ± SD: age, 24.67 ± 3.54 years; body weight, 54.96 ± 6.67 kg; and height, 162.2 ± 3.91 cm) who habitually wore high-heeled shoes participated in the study. They were asked to walk under nine combined conditions of three heights of shoe heels (0, 3, and 9 cm) and three carried loads (0%, 5%, and 10% of body weight). Temporospatial parameters and maximal joint angles in the sagittal and frontal planes of the hip, knee, and ankle on both limbs were studied.

RESULTS

It was found that high-heeled shoe wearing and asymmetrical load carrying altered temporospatial parameters and joint kinematics. With increased heel height and load weight, cadence decreased and stride length increased. The knee flexion angle increased with an increase in heel height, and the load served only to exacerbate the changes. Changes in the hip angle were mostly caused by asymmetrical load carrying, whereas angle changes in the ankle were mostly caused by an increase in heel height.

CONCLUSIONS

This study demonstrated that when high-heeled shoe wearing and asymmetrical load carrying are combined, changes at each joint are much greater than with high-heeled shoe wearing or load carrying alone.

[Endonasal endoscopic surgery in treatment of medial recus muscle entrapment: the management and effectiveness]

Objective:To explore the indications , surgery method and effect for the treatment of medial rectus muscle entrapment with endoscopic surgery.Method: Eight medial rectus muscle entrapment patients were enrolled in this study,3 cases underwent obital medial wall fracture reposition and medial rectus muscle adhesion decomposition surgery through endonasal endoscope,and 5 cases received obital medial wall fracture reposition surgery with endoscope through nasal cavity and lacrimal caruncle conjunctival incision. Result:The diplopia disappeared and eyeball abduction function recovered in 6 cases of medial rectus muscle entrapment patients within 2 months,and 1 case with each surgery had mild diplopia and eyeball incomplete abduction left.Conclusion:Adopting endonasal endoscopic surgery or dual approaches surgery with endonasal endoscopic and transcaruncular surgery were ideal methods for medial rectus muscle entrapment diseases.Surgery with endoscope has the characteristics of clear field and less damage.The surgery should be performed whithin 3 weeks, and the entrapment of medial rectus muscle can be resoved effectively.

Effects of Tai Ji Quan training on gait kinematics in older Chinese women with knee osteoarthritis: A randomized controlled trial

BACKGROUND

Although Tai Ji Quan has been shown to relieve pain and improve functional mobility in people with knee osteoarthritis (OA), little is known about its potential benefits on gait characteristics among older Chinese women who have a high prevalence of both radiographic and symptomatic knee OA. This study aims to assess the efficacy of a tailored Tai Ji Quan intervention on gait kinematics for older Chinese women with knee OA.

METHODS

A randomized controlled trial involving 46 older women in Shanghai, China, with clinically diagnosed knee OA. Randomized (1:1) participants received either a 60 min Tai Ji Quan session (n = 23) 3 times weekly or a 60 min bi-weekly educational session (n = 23) for 24 weeks. Primary outcomes were changes in gait kinematic measures from baseline to 24 weeks. Secondary outcomes included changes in scores on the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) and Short Physical Performance Battery (SPPB).

RESULTS

After 24 weeks the Tai Ji Quan group demonstrated better performance in gait velocity (mean difference, 8.40 cm/s, p = 0.01), step length (mean difference, 3.52 cm, p = 0.004), initial contact angle (mean difference, 2.19°, p = 0.01), and maximal angle (mean difference, 2.61°, p = 0.003) of flexed knees during stance phase compared to the control group. In addition, the Tai Ji Quan group showed significant improvement in WOMAC scores (p < 0.01) (mean difference, -4.22 points in pain, p = 0.002; -2.41 points in stiffness, p < 0.001; -11.04 points in physical function, p = 0.006) and SPPB scores (mean difference, 1.22 points, p < 0.001).

CONCLUSION

Among older Chinese women with knee OA, a tailored Tai Ji Quan intervention improved gait outcomes. The intervention also improved overall function as indexed by the WOMAC and SPPB. These results support the use of Tai Ji Quan for older Chinese adults with knee OA to both improve their functional mobility and reduce pain symptomatology.

Effect of Asymmetrical Load Carrying on Joint Kinetics of the Lower Extremity During Walking in High-Heeled Shoes in Young Women

BACKGROUND

Carrying a load asymmetrically and walking in high-heeled shoes are common in women. Knowledge of the effects of the two combined conditions on lower-limb kinetics is lacking. We sought to examine the effects of walking in high-heeled shoes and carrying an asymmetrical load on the joint kinetics of the lower extremity in young women.

METHODS

Fifteen participants were asked to walk in flat-heeled and 9-cm high-heeled shoes and to asymmetrically carry loads of 0% body weight (BW), 5% BW, and 10% BW. The three-dimensional joint moments of the hip, knee, and ankle in each of the walking conditions were studied through ground reaction force measurements and motion analysis.

RESULTS

Walking in high-heeled shoes and asymmetrically carrying a load of 5% or 10% BW resulted in significant differences in ankle joint moments of the loaded and unloaded lower limbs. Compared with walking in flat-heeled shoes, walking in high-heeled shoes and carrying a load asymmetrically significantly increased hip extension, hip abduction, knee extension, and knee adduction moments and decreased ankle plantar moment of the loaded leg. Walking in high-heeled shoes carrying a load of 10% BW resulted in greater significant changes in hip abduction, knee extension, and ankle dorsiflexion moments in the loaded leg than did carrying a load of 5% BW.

CONCLUSIONS

These findings indicate that walking in high-heeled shoes and asymmetrical load carrying create significant differences in joint loading between the two limbs and alter lower-extremity kinetics.

[Clinical analysis of cutaneous manifestations and related factors in patients with ulcerative colitis]

OBJECTIVE

To investigate the cutaneous manifestations in patients with ulcerative colitis (UC) and related factors.

METHODS

Patients admitted to Department of Gastroenterology Peking University First Hospital from January 1994 to December 2014 and diagnosed as UC were retrospectively enrolled in this study. Skin disorders were confirmed by the dermatologists. Clinical data were collected and compared between patients with and without cutaneous manifestations.

RESULTS

Among the total 373 UC patients, there were 34 cases (9.1%) with cutaneous manifestations, including 11 pyoderma gangrenosum, 8 erythema nodosum, 6 eczema, 3 psoriasis, 2 pemphigus, 1 granulomatous cheilitis, 1 ichthyosis, 1 acne rosacea, and 1 impetigo. The skin manifestations may occur after the diagnosis, simultaneously or even before the diagnosis of UC, which were 24, 7 and 3 patients respectively. The mean age in patients with skin lesions was (47.2±12.1) years, male to female ratio 0.79∶1. More patients with skin manifestations had severe activity of UC compared with non-skin group [50.0%(17/34) vs 25.1%(85/339), P=0.01]. In addition, the proportion of extensive colitis in skin lesion group was significantly higher than that in non-skin group [76.5%(26/34) vs 54.6%(185/339), P=0.04].

CONCLUSIONS

The cutaneous manifestations associated with UC are polymorphic, erythema nodosums and pyoderma gangrenosums are the most common skin lesions seen in UC patients. Skin lesions occur concurrently, pre or post the diagnosis of UC. Skin lesions in UC patients suggest more severe disease activity. Clinicians need to pay more attention to this group.

Lower limb joint angles and ground reaction forces in forefoot strike and rearfoot strike runners during overground downhill and uphill running

This study investigated the normal and parallel ground reaction forces during downhill and uphill running in habitual forefoot strike and habitual rearfoot strike (RFS) runners. Fifteen habitual forefoot strike and 15 habitual RFS recreational male runners ran at 3 m/s ± 5% during level, uphill and downhill overground running on a ramp mounted at 6° and 9°. Results showed that forefoot strike runners had no visible impact peak in all running conditions, while the impact peaks only decreased during the uphill conditions in RFS runners. Active peaks decreased during the downhill conditions in forefoot strike runners while active loading rates increased during downhill conditions in RFS runners. Compared to the level condition, parallel braking peaks were larger during downhill conditions and parallel propulsive peaks were larger during uphill conditions. Combined with previous biomechanics studies, our findings suggest that forefoot strike running may be an effective strategy to reduce impacts, especially during downhill running. These findings may have further implications towards injury management and prevention.

Ottawa Panel Evidence-Based Clinical Practice Guidelines for Foot Care in the Management of Juvenile Idiopathic Arthritis

OBJECTIVE

To create evidence-based guidelines evaluating foot care interventions for the management of juvenile idiopathic arthritis (JIA).

DATA SOURCES

An electronic literature search of the following databases from database inception to May 2015 was conducted: MEDLINE (Ovid), EMBASE (Ovid), Cochrane CENTRAL, and clinicaltrials.gov.

STUDY SELECTION

The Ottawa Panel selection criteria targeted studies that assessed foot care or foot orthotic interventions for the management of JIA in those aged 0 to ≤18 years. The Physiotherapy Evidence Database scale was used to evaluate study quality, of which only high-quality studies were included (score, ≥5). A total of 362 records were screened, resulting in 3 full-text articles and 1 additional citation containing supplementary information included for the analysis.

DATA EXTRACTION

Two reviewers independently extracted study data (intervention, comparator, outcome, time period, study design) from the included studies by using standardized data extraction forms. Directed by Cochrane Collaboration methodology, the statistical analysis produced figures and graphs representing the strength of intervention outcomes and their corresponding grades (A, B, C+, C, C-, D+, D, D-). Clinical significance was achieved when an improvement of ≥30% between the intervention and control groups was present, whereas P>.05 indicated statistical significance. An expert panel Delphi consensus (≥80%) was required for the endorsement of recommendations.

DATA SYNTHESIS

All included studies were of high quality and analyzed the effects of multidisciplinary foot care, customized foot orthotics, and shoe inserts for the management of JIA. Custom-made foot orthotics and prefabricated shoe inserts displayed the greatest improvement in pain intensity, activity limitation, foot pain, and disability reduction (grades A, C+).

CONCLUSIONS

The use of customized foot orthotics and prefabricated shoe inserts seems to be a good choice for managing foot pain and function in JIA.

Effect of low temperatures on BAX and BCL2 proteins in rats with spinal cord ischemia reperfusion injury

We evaluated changes in BAX and BCL2 expression levels after spinal cord ischemia/reperfusion injury (SCII) and hypothermia during operations in rats. Eighty rats were divided into four groups: Group A (N = 20, 18°C); Group B (N = 20, 28°C); Group C (N = 20, room temperature); and Group D (N = 20, sham operation control). Spinal cord ischemia was induced for 90 min. Hypothermia was induced 15 min before, and maintained during ischemia, followed by heating to normothermia for 30 min after reperfusion. Motor function of the lower limbs was evaluated according to the Tarlov score at 72 and 168 h. For each rat, spinal cord samples were taken at 6, 24, 72 h, and 1 week to evaluate the histopathological changes, neuronal apoptosis, and BAX and BCL2 expression levels. Compared with normothermia, hypothermia significantly improved hind limb function; Group B achieved a higher score than Group A. Group D showed no neurologic deficiency, while the other groups showed various degrees. Group C exhibited greater neuronal apoptosis, higher BAX expression, but lower BCL2 expression than the other groups. Compared with Group A, BAX was expressed less and BCL2 more in Group B, and there was less apoptosis in Group B. Hypothermia preserves hind limb motor function and reduces neuronal death, thereby protecting rats from SCII. The spinal cord may be protected from SCII by inhibition of BAX and activation of BCL2. However, deep hypothermia may inhibit the expression of BCL2, resulting in a worse outcome than mild hypothermia.

Biomass viability: An experimental study and the development of an empirical mathematical model for submerged membrane bioreactor

This study investigates the influence of key biomass parameters on specific oxygen uptake rate (SOUR) in a sponge submerged membrane bioreactor (SSMBR) to develop mathematical models of biomass viability. Extra-cellular polymeric substances (EPS) were considered as a lumped parameter of bound EPS (bEPS) and soluble microbial products (SMP). Statistical analyses of experimental results indicate that the bEPS, SMP, mixed liquor suspended solids and volatile suspended solids (MLSS and MLVSS) have functional relationships with SOUR and their relative influence on SOUR was in the order of EPS>bEPS>SMP>MLVSS/MLSS. Based on correlations among biomass parameters and SOUR, two independent empirical models of biomass viability were developed. The models were validated using results of the SSMBR. However, further validation of the models for different operating conditions is suggested.

Transcriptome analysis of adiposity in domestic ducks by transcriptomic comparison with their wild counterparts

Excessive adiposity is a major problem in the duck industry, but its molecular mechanisms remain unknown. Genetic comparisons between domestic and wild animals have contributed to the exploration of genetic mechanisms responsible for many phenotypic traits. Significant differences in body fat mass have been detected between domestic and wild ducks. In this study, we used the Peking duck and Anas platyrhynchos as the domestic breed and wild counterpart respectively and performed a transcriptomic comparison of abdominal fat between the two breeds to comprehensively analyze the transcriptome basis of adiposity in ducks. We obtained approximately 350 million clean reads; assembled 61 250 transcripts, including 23 699 novel ones; and identified alternative 5' splice sites, alternative 3' splice sites, skipped exons and retained intron as the main alternative splicing events. A differential expression analysis between the two breeds showed that 753 genes exhibited differential expression. In Peking ducks, some lipid metabolism-related genes (IGF2, FABP5, BMP7, etc.) and oncogenes (RRM2, AURKA, CYR61, etc.) were upregulated, whereas genes related to tumor suppression and immunity (TNFRSF19, TNFAIP6, IGSF21, NCF1, etc.) were downregulated, suggesting adiposity might closely associate with tumorigenesis in ducks. Furthermore, 280 576 single-nucleotide variations were found differentiated between the two breeds, including 8641 non-synonymous ones, and some of the non-synonymous ones were found enriched in genes involved in lipid-associated and immune-associated pathways, suggesting abdominal fat of the duck undertakes both a metabolic function and immune-related function. These datasets enlarge our genetic information of ducks and provide valuable resources for analyzing mechanisms underlying adiposity in ducks.

Quantitative study of the quadratic magneto-optical Kerr effects in Fe films

We present a rotating field method to separate the linear and quadratic magneto-optical Kerr effects (LMOKE and QMOKE) in Fe/GaAs(001) films. The LMOKE is isotropic in crystal orientation, while the QMOKE has both isotropic and anisotropic contributions. The experimental observation is well explained by Yeh's 4×4 matrix formalism. We also report the incident angle and the thickness dependences of the LMOKE and QMOKE, and extract the material's index of refraction n and the magneto-optical coupling constant K and G. The study gives a full description of the Kerr effect in Fe films, and the proposed method can be applied to other magneto-optical coupling systems.

A microfluidic device enabling high-efficiency single cell trapping

Single cell trapping increasingly serves as a key manipulation technique in single cell analysis for many cutting-edge cell studies. Due to their inherent advantages, microfluidic devices have been widely used to enable single cell immobilization. To further improve the single cell trapping efficiency, this paper reports on a passive hydrodynamic microfluidic device based on the "least flow resistance path" principle with geometry optimized in line with corresponding cell types. Different from serpentine structure, the core trapping structure of the micro-device consists of a series of concatenated T and inverse T junction pairs which function as bypassing channels and trapping constrictions. This new device enhances the single cell trapping efficiency from three aspects: (1) there is no need to deploy very long or complicated channels to adjust flow resistance, thus saving space for each trapping unit; (2) the trapping works in a "deterministic" manner, thus saving a great deal of cell samples; and (3) the compact configuration allows shorter flowing path of cells in multiple channels, thus increasing the speed and throughput of cell trapping. The mathematical model of the design was proposed and optimization of associated key geometric parameters was conducted based on computational fluid dynamics (CFD) simulation. As a proof demonstration, two types of PDMS microfluidic devices were fabricated to trap HeLa and HEK-293T cells with relatively significant differences in cell sizes. Experimental results showed 100% cell trapping and 90% single cell trapping over 4 × 100 trap sites for these two cell types, respectively. The space saving is estimated to be 2-fold and the cell trapping speed enhancement to be 3-fold compared to previously reported devices. This device can be used for trapping various types of cells and expanded to trap cells in the order of tens of thousands on 1-cm(2) scale area, as a promising tool to pattern large-scale single cells on specific substrates and facilitate on-chip cellular assay at the single cell level.

The effect of unilateral hockey bag carriage on the muscle activities of the trunk and lower limb of young healthy males during gait

This study explored the trunk and lower limb muscle activity of 15 males during unilateral hockey bag carriage of 10%, 20%, and 30% of one's body weight (BW) compared with without a load during walking. The electromyography (EMG) activities of the left and right erector spinae, rectus abdominis, gluteus maximus, rectus femoris, vastus medialis, biceps femoris, semitendinosus, and the medial gastrocnemius were studied. A 2-way repeated measures analysis of variance (ANOVA) was used to examine the differences between the load weight and muscle side. Results showed significant increase in peak EMG and iEMG in the carrying side vastus medialis, rectus abdominis, semitendinosus, and gastrocnemii (p < 0.05) at the 30% BW load. The noncarrying side showed a greater peak EMG in the semitendinosus and rectus femoris at the 30% BW load when compared with the carrying side (p < 0.05). It was concluded that unilateral hockey bag carriage is similar to both backpack and side-pack carriage styles.

Repair of cartilage defects in BMSCs via CDMP1 gene transfection

This study aimed at investigating the ability of cartilage-derived morphogenetic protein 1 (CDMP1) gene-transfected bone marrow mesenchymal stem cells (BMSCs) loaded on the poly(lactic-co-glycolic acid) (PLGA) scaffold for the repair of laryngeal cartilage defects and make a preliminary assessment of its repair effect. The mRNA and protein expressions of hCDMP1 were detected by reverse transcriptase-polymerase chain reaction and Western blotting. The expression of type II collagen (Col II) and glycosaminoglycan (GAG) were detected by immunohistochemistry. The cytoskeletal culture systems before and after transfection were transplanted into the rabbit full-thickness defects of thyroid cartilage for observation of the repair of cartilage defects from general and histological aspects. The exogenous hCDMP1 gene could be successfully transplanted into BMSCs through adenovirus infection to obtain a stable expression. Compared with the control group, hCDMP1 gene-transfected BMSCs had enhanced secretory abilities of Col II, GAG, and other cartilage-specific matrices, with a trend of promoting cartilage differentiation. The transfected cytoskeletal complexes could more effectively repair laryngeal cartilage defects. hCDMP1 gene-transfected BMSCs/PLGA 3-D biological scaffold compounds transplanted into animal bodies could effectively repair laryngeal cartilage defects.

Prediction equations of energy expenditure in Chinese youth based on step frequency during walking and running

PURPOSE

This study set out to examine the relationship between step frequency and velocity to develop a step frequency-based equation to predict Chinese youth's energy expenditure (EE) during walking and running.

METHOD

A total of 173 boys and girls aged 11 to 18 years old participated in this study. The participants walked and ran on a treadmill at speeds of 3 km/hr, 4 km/hr, 5 km/hr, 6 km/hr, 7 km/hr, and 8 km/hr. EE was measured using indirect calorimetry of open circuit spirometry (Cosmed K4b2 metabolic analyzer). Using multiple regression analysis, the relationship between step frequency and velocity was first examined, and the prediction equation of EE based on step frequency, age, and gender was derived.

RESULTS

The hypothesized relationship between step frequency and velocity was confirmed and an accurate (R2 = .78) EE prediction equation was derived: NetEE = - 13.7744 + 1.8004 (step frequency) - 5.5715 (age) - 11.5244 (gender).

CONCLUSION

A step frequency-, age-, and gender-based equation was derived to predict the EE of youth during walking and running. The equation can be used to develop a simple device to estimate EE during walking and running in this population.