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QiHong Wu,1 RongRong Jin,2 Ting Feng,1 Li Liu,2 Li Yang,2 YuHong Tao,3 James M Anderson,4,5 Hua Ai,2,6 Hong Li1,3 1Key Laboratory of Obstetrics, Gynecology, Pediatric Disease, and Birth Defects, Ministry of Education, West China Second University Hospital, 2National Engineering Research Center for Biomaterials, 3Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China; 4Department of Biomedical Engineering, 5Department of Pathology, Case Western Reserve University, Cleveland, OH, US; 6Department of Radiology, West China Hospital, Sichuan University, Chengdu, China Abstract: Superparamagnetic iron oxide nanoparticles have been widely used in biomedical applications, but understanding of their interactions with the biological immune system is relatively limited. This work is focused on dextran-coated iron oxide nanoparticles and their induced autophagy in human monocytes. We found that these nanoparticles can be taken up by human monocytes, followed by localization within vesicles or free in cytoplasm. Autophagosome formation was observed with increased expression of LC3II protein, the specific marker of autophagy. The autophagy substrate p62 was degraded in a dose-dependent manner, and autophagy was blocked by autophagy (or lysosome) inhibitors alone or along with iron oxide nanoparticles, indicating that autophagosome accumulation was mainly due to autophagy induction, rather than blockade of autophagy flux. Interestingly, iron oxide nanoparticles increased the viability of human monocytes, but the mechanism was not clear. We further found that inhibition of autophagy mostly attenuated the survival of cells, with acceleration of the inflammation induced by these nanoparticles. Taken together, autophagic activation in human monocytes may play a protective role against the cytotoxicity of iron oxide nanoparticles. Keywords: autophagy, cytotoxicity, human monocytes, inflammation, iron oxide nanoparticles

Jamie B Warren,1 William E Lambert,2 Rongwei Fu,2 JoDee M Anderson,1 Alison B Edelman31Department of Pediatrics, 2Department of Public Health and Preventive Medicine, 3Department of Obstetrics and Gynecology, Oregon Health and Science University, Portland, OR, USABackground: Millennium Development Goal 4 calls for the reduction of the under-five mortality rate by two-thirds between 1990 and 2015. To reach this goal, neonatal mortality must be decreased. The lack of information on global neonatal and perinatal mortality impedes appropriate implementation of interventions, as vital registration systems are not available for the majority of the world's neonatal deaths. Verbal autopsy (VA) is a tool that has been used to determine cause of death. Recent studies have attempted to standardize and validate the use of this tool in resource-limited areas. The World Health Organization (WHO) International Standard VA Questionnaire was used to conduct a needs assessment in nine rural Peruvian villages. The goal was to determine the neonatal mortality rate (NMR), perinatal mortality rate (PMR), and causes of, and risk factors for, death in these villages.Methods: Eligible women were interviewed using the WHO International Standard VA Questionnaire or a set of questions based on the WHO VA Questionnaire. NMR and PMR were calculated using a generalized estimating equation model. Three neonatologists independently reviewed VA records to provide cause of death determination. Reviewer agreement was assessed using percent agreement. Fisher's exact test was used to determine risk factors associated with death.Results: The NMR was 31.4 per 1000 live births and the PMR was 49.7 per 1000 pregnancies. The main contributor to neonatal death was infection (43%). Percent agreement among reviewers was 90.5% and 38.9% for cause of neonatal death and stillbirth, respectively. Risk factors for death were pregnancy with twins (P = 0.001), preterm delivery (P = 0.003), and cesarean section delivery (P = 0.049).Conclusion: The WHO VA proved useful for NMR and PMR calculation, cause of death determination, and risk factor identification. Information gathered in this needs assessment will allow for the design and implementation of tailored interventions.Keywords: neonatal mortality, perinatal mortality, verbal autopsy, needs assessment

RadioAstron space-ground very long baseline interferometry observations of the pulsar B0950+08, conducted with the 10 m Space Radio Telescope in conjunction with the Arecibo 300 m telescope and the Westerbork Synthesis Radio Telescope at a frequency of 324 MHz were analyzed in order to investigate plasma inhomogeneities in the direction of this nearby pulsar. The observations were conducted at a spacecraft distance of 330, 000 km, resulting in a projected baseline of 220, 000 km, providing the greatest angular resolution ever achieved at meter wavelengths. Our analysis is based on fundamental behavior of structure and coherence functions. We find that the pulsar shows scintillation on two frequency scales, both much less than the observing frequency, but modulation is less than 100%. We infer that the scattering is weak, but a refracting wedge disperses the scintillation pattern. The refraction angle of this "cosmic prism" is measured as θ0 = 1.1-4.4 mas, with the refraction direction being approximately perpendicular to the observer velocity. We show that the observed parameters of scintillation effects indicate that two plasma layers lie along the line of sight to the pulsar, at distances of 4.4-16.4 pc and 26-170 pc, and traveling in different directions relative to the line of sight. Spectra of turbulence for the two layers are found to follow a power law with the indices γ1 = γ2 = 3.00 ± 0.08, significantly different from the index expected for a Kolmogorov spectrum of turbulence, γ = 11/3.

OBJECTIVES: To examine the effectiveness in screening for triploidy at 11 weeks to 13 weeks and 6 days of gestation by the combined use of the risk algorithms for trisomies 21, 18 and 13 based on maternal age, fetal nuchal translucency (NT) thickness, fetal heart rate (FHR) and maternal serum free beta-hCG and PAPP-A. METHODS: Prospective screening for trisomy 21, including 56 376 normal singleton pregnancies and 31 cases with triploidy (24 digynic and 7 diandric). Patient-specific risks for trisomies 21, 18 and 13 were calculated by multiplying the age related risk for trisomies 21, 18 and 13 with the likelihood ratio (LR) for fetal NT and with a combined LR for FHR, free beta-hCG and PAPP-A, respectively. Detection rates (DRs) and false positive rates (FPRs) for triploidy were calculated by taking the proportion with risks above a given risk threshold and standardized for maternal age according to the distribution of pregnancies in England and Wales in 2000 to 2002. RESULTS: In digynic triploidy, free beta-hCG was 0.16 (range 0.02-0.95) MoM and PAPP-A was 0.06 (range 0.02-0.47) MoM and the respective values for diandric triploidy were 8.74 (range 2.83-47.0) and 0.74 (range 0.32-1.51) MoM. Use of the trisomy 21 algorithm identified 5 of the 7 diandric cases and 3 of the 24 digynic ones at a 3% FPR. Combined use of the risk algorithms for trisomies 18 and 13 identified 20 of the 24 cases with the digynic triploidy at the FPR of 0.2%. When screen positivity was defined by a 3% FPR using the algorithm for trisomy 21 and an additional 0.2% FPR using the algorithms for trisomies 18 and 13, the total FPR was 3.1% and the DR was 84%. CONCLUSIONS: A beneficial side-effect of first trimester combined screening for trisomies is the detection of a high proportion of fetuses with triploidy. Copyright (c) 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Recent advances in molecular biology have elucidated some of the mechanisms that regulate skeletal muscle growth. Logically, muscle physiologists have applied these innovations to the study of resistance exercise (RE), as RE represents the most potent natural stimulus for growth in adult skeletal muscle. However, as this molecular-based line of research progresses to investigations in humans, scientists must appreciate the fundamental principles of RE to effectively design such experiments. Therefore, we present herein an updated paradigm of RE biology that integrates fundamental RE principles with the current knowledge of muscle cellular and molecular signalling. RE invokes a sequential cascade consisting of: (i) muscle activation; (ii) signalling events arising from mechanical deformation of muscle fibres, hormones, and immune/inflammatory responses; (iii) protein synthesis due to increased transcription and translation; and (iv) muscle fibre hypertrophy. In this paradigm, RE is considered an 'upstream' signal that determines specific downstream events. Therefore, manipulation of the acute RE programme variables (i.e. exercise choice, load, volume, rest period lengths, and exercise order) alters the unique 'fingerprint' of the RE stimulus and subsequently modifies the downstream cellular and molecular responses. [ABSTRACT FROM AUTHOR]

The purpose of this investigation was to examine the influence of upper-body static stretching and dynamic stretching on upper-body muscular performance. Eleven healthy men, who were National Collegiate Athletic Association Division I track and field athletes (age, 19.6 +/- 1.7 years; body mass, 93.7 +/- 13.8 kg; height, 183.6 +/- 4.6 cm; bench press 1 repetition maximum [1RM], 106.2 +/- 23.0 kg), participated in this study. Over 4 sessions, subjects participated in 4 different stretching protocols (i.e., no stretching, static stretching, dynamic stretching, and combined static and dynamic stretching) in a balanced randomized order followed by 4 tests: 30% of 1 RM bench throw, isometric bench press, overhead medicine ball throw, and lateral medicine ball throw. Depending on the exercise, test peak power (Pmax), peak force (Fmax), peak acceleration (Amax), peak velocity (Vmax), and peak displacement (Dmax) were measured. There were no differences among stretch trials for Pmax, Fmax, Amax, Vmax, or Dmax for the bench throw or for Fmax for the isometric bench press. For the overhead medicine ball throw, there were no differences among stretch trials for Vmax or Dmax. For the lateral medicine ball throw, there was no difference in Vmax among stretch trials; however, Dmax was significantly larger (p

BACKGROUND: Female athletes land from a jump with greater knee valgus and ankle pronation/eversion. Excessive valgus and pronation have been linked to risk of anterior cruciate ligament injury. A medially posted orthosis decreases component motions of knee valgus such as foot pronation/eversion and tibial internal rotation. HYPOTHESIS: We hypothesized a medial post would decrease knee valgus and ankle pronation/eversion during drop-jump landings in NCAA-I female athletes. STUDY DESIGN: Controlled laboratory study. METHODS: Knee and ankle 3-dimensional kinematics were measured using high-speed motion capture in 10 National Collegiate Athletic Association Division I female athletes during a drop-jump landing with and without a medial post. Analysis of variance was used to determine differences in posting condition, t tests were used to determine dominant-nondominant differences, and the Pearson correlation coefficient was used to determine relationships between variables. RESULTS: Significant differences were found for all measures in the posted condition. A medial post decreased knee valgus at initial contact (1.24 degrees , P < .01) and maximum angle (1.21 degrees , P < .01). The post also decreased ankle pronation/eversion at initial contact (0.77 degrees , P < .01) and maximum angle (0.95 degrees , P = .039). CONCLUSION: The authors have demonstrated a significant decrease in knee valgus and ankle pronation/eversion during a drop jump with a medial post placed in the athletes' shoes. CLINICAL RELEVANCE: A medial post may be a potential means to decrease risk of anterior cruciate ligament injury. [ABSTRACT FROM AUTHOR]

Knowledge translation is an interactive, dynamic approach to the uptake of evidence-based knowledge. In this article, the authors present a collaborative model for knowledge translation that grew out of a program of research focusing on the experiences of patients from ethnoculturally diverse groups as they were discharged home from hospital. Research findings highlight issues around gaps in the continuity of services and language and communication. The authors discuss a number of knowledge translation initiatives that were developed to address these gaps. Key to the success of this process has been a collaborative relationship between researchers and practitioners that is grounded in the shared goal of knowledge translation to support ethically sound decision-making in the delivery of health-care services. [ABSTRACT FROM AUTHOR]

Significant scientific evidence documents the deleterious effects of hypohydration (reduced total body water) on endurance exercise performance; however, the influence of hypohydration on muscular strength, power and high-intensity endurance (maximal activities lasting >30 seconds but <2 minutes) is poorly understood due to the inconsistent results produced by previous investigations. Several subtle methodological choices that exacerbate or attenuate the apparent effects of hypohydration explain much of this variability. After accounting for these factors, hypohydration appears to consistently attenuate strength (by ~=2%), power (by ~=3%) and high-intensity endurance (by ~10%), suggesting alterations in total body water affect some aspect of force generation. Unfortunately, the relationships between performance decrement and crucial variables such as mode, degree and rate of water loss remain unclear due to a lack of suitably uninfluenced data. The physiological demands of strength, power and high-intensity endurance couple with a lack of scientific support to argue against previous hypotheses that suggest alterations in cardiovascular, metabolic and/or buffering function represent the performance-reducing mechanism of hypohydration. On the other hand, hypohydration might directly affect some component of the neuromuscular system, but this possibility awaits thorough evaluation. A critical review of the available literature suggests hypohydration limits strength, power and high-intensity endurance and, therefore, is an important factor to consider when attempting to maximise muscular performance in athletic, military and industrial settings. [ABSTRACT FROM AUTHOR]

Context: Theoretically, the risk of compartment syndrome is increased during creatine monohydrate (CrM) supplementation because of intracellular fluid retention in muscle cells and the overall increased size of the muscle tissue. Whether this change in intracellular fluid is associated with an increase in anterior compartment pressure in the lower leg when subjects are under thermal stress is unknown.Objective: To assess the influence of CrM on the resting and postexercise anterior compartment pressure of the lower leg in mildly to moderately dehydrated males exercising in the heat.Design: Double-blind, randomized, crossover design.Setting: Human Performance Laboratory.Patients or Other Participants: Eleven well-trained, non- heat-acclimated, healthy males (age = 22 +/- 2 years, height = 181.1 +/- 7 cm, mass = 78.4 +/- 4.2 kg, Vo(2)max = 50.5 +/- 3.4 mL.kg(-1).min(-1)).Intervention(s): Subjects were supplemented with 21.6 g/d of CrM or placebo for 7 days. On day 7, they performed 2 hours of submaximal exercise, alternating 30 minutes of walking with 30 minutes of cycling in the heat, resulting in approximately 2% dehydration. This was followed by an 80-minute heat tolerance test (temperature = 33.5 +/- 0.5 degrees C, humidity = 41.0 +/- 12%), which included 12 repetitions of a 3-minute walk (pace = 4.0 +/- 0.1 miles/h, intensity = 37.1 +/- 6.1% Vo(2)max) alternating with a 1-minute, high-intensity run (pace = 11.8 +/- 0.4 miles/h, intensity = 115.0 +/- 5.6% Vo(2)max), resulting in an additional 2% decrease in body weight.Main Outcome Measures: Before supplementation and on day 7 of supplementation, anterior compartment pressure was measured at rest, after dehydration, and at 1, 3, 5, 10, 15, and 60 minutes after the heat tolerance test. Analysis of variance with repeated measures was calculated to compare differences within the trials and time points and to identify any interaction between trial and time.Results: The CrM intake was associated with an increase in body weight (P < .05). A moderate effect size was noted for compartment pressures between the trials for the differences between predehydration and postdehydration (eta(2) = 0.414). This effect diminished substantially by 3 minutes after the heat tolerance test. Compared with the placebo trial, the change in anterior compartment pressure from rest to dehydration was greater, as was the change from rest to 1 minute after the heat tolerance test (P < .05) during the CrM trial.Conclusions: A 7-day loading dose of CrM increased anterior compartment pressures after dehydration and immediately after the heat tolerance tests, but the changes did not induce symptoms and the pressure changes were transient. [ABSTRACT FROM AUTHOR]