Structure, Spin Correlations, and Magnetism of the S = 1/2 Square-Lattice Antiferromagnet Sr2CuTe1-xWxO6 (0 ≤ x ≤ 1).

Quantum spin liquids are highly entangled magnetic states with exotic properties. The S = 1/2 square-lattice Heisenberg model is one of the foundational models in frustrated magnetism with a predicted, but never observed, quantum spin liquid state. Isostructural double perovskites Sr2CuTeO6 and Sr2CuWO6 are physical realizations of this model but have distinctly different types of magnetic order and interactions due to a d10/d0 effect. Long-range magnetic order is suppressed in the solid solution Sr2CuTe1-xWxO6 in a wide region of x = 0.05-0.6, where the ground state has been proposed to be a disorder-induced spin liquid. Here, we present a comprehensive neutron scattering study of this system. We show using polarized neutron scattering that the spin liquid-like x = 0.2 and x = 0.5 samples have distinctly different local spin correlations, which suggests that they have different ground states. Low-temperature neutron diffraction measurements of the magnetically ordered W-rich samples reveal magnetic phase separation, which suggests that the previously ignored interlayer coupling between the square planes plays a role in the suppression of magnetic order at x ≈ 0.6. These results highlight the complex magnetism of Sr2CuTe1-xWxO6 and hint at a new quantum critical point between 0.2 < x < 0.4.

Partitioning the Two-Leg Spin Ladder in Ba2Cu1 - x Zn x TeO6: From Magnetic Order through Spin-Freezing to Paramagnetism.

Ba2CuTeO6 has attracted significant attention as it contains a two-leg spin ladder of Cu2+ cations that lies in close proximity to a quantum critical point. Recently, Ba2CuTeO6 has been shown to accommodate chemical substitutions, which can significantly tune its magnetic behavior. Here, we investigate the effects of substitution for non-magnetic Zn2+ impurities at the Cu2+ site, partitioning the spin ladders. Results from bulk thermodynamic and local muon magnetic characterization on the Ba2Cu1 - x Zn x TeO6 solid solution (0 ≤ x ≤ 0.6) indicate that Zn2+ partitions the Cu2+ spin ladders into clusters and can be considered using the percolation theory. As the average cluster size decreases with increasing Zn2+ substitution, there is an evolving transition from long-range order to spin-freezing as the critical cluster size is reached between x = 0.1 to x = 0.2, beyond which the behavior became paramagnetic. This demonstrates well-controlled tuning of the magnetic disorder, which is highly topical across a range of low-dimensional Cu2+-based materials. However, in many of these cases, the chemical disorder is also relatively strong in contrast to Ba2CuTeO6 and its derivatives. Therefore, Ba2Cu1 - x Zn x TeO6 provides an ideal model system for isolating the effect of defects and segmentation in low-dimensional quantum magnets.

The Effects of Preimplantation Genetic Testing for Aneuploidy (PGT-A) on Patient-Important Outcomes in Embryo Transfer Cases: A Meta-Analysis.

Background: The aim of this study was to evaluate the effect of preimplantation genetic testing for aneuploidy (PGT-A) on patient-important reproductive outcomes after in vitro fertilization (IVF). Methods: Randomized and non-randomized studies have been sought in Ovid, MEDLINE, EMBASE, Web of Science, Scopus, and Cochrane Central Register of Controlled Trials since each database's inception through May 2021. Main keywords used for the search strategy included "Embryo transfer", "In vitro fertilization", "DNA sequencing", and "Comparative genome hybridization". Studies were screened independently and in duplicate. Results: Ten studies were finally analyzed, representing a total of 2630 embryo transfers. The pooled OR for live birth rates were 1.45 (95%CI 0.24-8.78, I2 96%) and 1.66 (95%PI 0.15-18.01, 95%CI 0.98-2.83, I2 81%) derived from the NRSIs and the RCTs, respectively, in which the miscarriage rate were 1.25 (95%CI 0.19-8.33, I2 70%) and 0.57 (95%PI 0.06-5.34, 95%CI 0.27-1.21, I2 53%), and clinical pregnancy rates were 3.08 (95%CI 2.22-4.29, I2 0%) and 1.43 (95%PI 0.38-5.42, 95%CI 0.96-2.13, I2 68%). Influence analyses showed a greater treatment effect when excluding studies without patients at advanced maternal age. Conclusion: There seems to be no significant difference in reproductive outcomes when using PGT-A in the general population; however, the procedure seems advantageous for patients at advanced maternal age. Nevertheless, this warrants caution when recommending the procedure to all couples seeking ART, as the current possible benefits may not justify the additional costs for all groups of patients.

Uncovering the Kagome Ferromagnet within a Family of Metal-Organic Frameworks.

Kagome networks of ferromagnetically or antiferromagnetically coupled magnetic moments represent important models in the pursuit of a diverse array of novel quantum and topological states of matter. Here, we explore a family of Cu2+-containing metal-organic frameworks (MOFs) bearing kagome layers pillared by ditopic organic linkers with the general formula Cu3(CO3)2(x)3·2ClO4 (MOF-x), where x is 1,2-bis(4-pyridyl)ethane (bpe), 1,2-bis(4-pyridyl)ethylene (bpy), or 4,4'-azopyridine (azpy). Despite more than a decade of investigation, the nature of the magnetic exchange interactions in these materials remained unclear, meaning that whether the underlying magnetic model is that of an kagome ferromagnet or antiferromagnet is unknown. Using single-crystal X-ray diffraction, we have developed a chemically intuitive crystal structure for this family of materials. Then, through a combination of magnetic susceptibility, powder neutron diffraction, and muon-spin spectroscopy measurements, we show that the magnetic ground state of this family consists of ferromagnetic kagome layers that are coupled antiferromagnetically via their extended organic pillaring linkers.

Neutralising antibodies to West Nile virus detected in horses in Windhoek, Namibia.

ABSTRACT: West Nile virus (WNV) is a vector-borne virus maintained in nature by a bird-mosquito cycle. However, it can occasionally and accidentally infect horses and human beings, leading to sometimes severe or even fatal outcomes in these species. Therefore, the monitoring of its circulation and disease occurrence is of relevance. Unfortunately, it is underdiagnosed or not diagnosed in several African counties, including Namibia, where no data is currently available for horses. In this study, 98 horses in three different stables in the Windhoek city area were investigated. They were found to have a seroprevalence of approximately 7%. Positive reactions were seen at all three stables, suggesting a greater than expected prevalence of the virus. This is the first report of serological evidence for the presence of the virus in horses in Nambia. Even though clinical signs were not reported in any of the stables from which the sera were derived, the seroprevalence to the virus suggests that horses with high genetic and/or economic value could benefit from vaccination against WNV. Because of the zoonotic potential of the virus, these findings are also of significance to human health authorities.

Site-Selective d10/d0 Substitution in an S = 1/2 Spin Ladder Ba2CuTe1-xWxO6 (0 ≤ x ≤ 0.3).

Isovalent nonmagnetic d10 and d0 B″ cations have proven to be a powerful tool for tuning the magnetic interactions between magnetic B' cations in A2B'B″O6 double perovskites. Tuning is facilitated by the changes in orbital hybridization that favor different superexchange pathways. This can produce alternative magnetic structures when B″ is d10 or d0. Furthermore, the competition generated by introducing mixtures of d10 and d0 cations can drive the material into the realms of exotic quantum magnetism. Here, Te6+ d10 was substituted by W6+ d0 in the hexagonal perovskite Ba2CuTeO6, which possesses a spin ladder geometry of Cu2+ cations, creating a Ba2CuTe1-xWxO6 solid solution (x = 0-0.3). We find W6+ is almost exclusively substituted for Te6+ on the corner-sharing site within the spin ladder, in preference to the face-sharing site between ladders. The site-selective doping directly tunes the intraladder, Jrung and Jleg, interactions. Modeling the magnetic susceptibility data shows the d0 orbitals modify the relative intraladder interaction strength (Jrung/Jleg) so the system changes from a spin ladder to isolated spin chains as W6+ increases. This further demonstrates the utility of d10 and d0 dopants as a tool for tuning magnetic interactions in a wide range of perovskites and perovskite-derived structures.

Learning curve in robotic-assisted lobectomy for non-small cell lung cancer is not steep after experience in video-assisted lobectomy; single-surgeon experience using cumulative sum analysis.

BACKGROUND: Robotic assistance in lung lobectomy has been suggested to enhance the adoption of minimally invasive techniques among surgeons. However, little is known of learning curves in different minimally invasive techniques. We studied learning curves in robotic-assisted versus video- assisted lobectomies for lung cancer. METHODS: A single surgeon performed his first 75 video-assisted thoracic surgery (VATS) lobectomies from April 2007 to November 2012, and his 75 first robotic-assisted thoracic surgery (RATS) lobectomies between August 2011 and May 2018. A retrospective chart review was done. Cumulative sum (CUSUM) analysis was used to identify the learning curve. RESULTS: No operative deaths occurred for VATS patients or RATS patients. Conversion-to-open rate was significantly lower in the RATS group (2.7% vs. 13.3%, p = 0.016). Meanwhile, 90-day mortality (1.3% vs. 5.3%, p = 0.172), postoperative complications (24% vs. 24%, p = 0.999), re- operation rates (4% vs. 5.3%, p = 0.688), operation time (170±56 min vs. 178±66 min, p = 0.663) and length of stay (8.9 ± 7.9 days vs. 8.2 ± 5.8 days, p = 0.844) were similar between the two groups. Based on CUSUM analysis, learning curves were similar for both procedures, although slightly shorter for RATS (proficiency obtained with 53 VATS cases vs. 45 RATS cases, p = 0.198). CONCLUSIONS: Robotic-assisted thoracoscopic lung lobectomy can be implemented safely and efficiently in an expert center with earlier experience in VATS lobectomies. However, there seems to be a learning curve of its own despite the surgeon's previous experience in conventional thoracoscopic surgery.

Association between thyroid autoimmunity and ovarian reserve in women with hypothyroidism.

BACKGROUND: The ovarian function and therefore the ovarian reserve may be compromised by the pathogenesis of autoimmune diseases of which, Hashimoto's thyroiditis (HT) is the most common in women of reproductive age. Furthermore, a prolonged reduction in thyroid hormone concentration results in a broad spectrum of reproductive alteration. Previous reports in the literature have been controversial regarding the impact of hypothyroidism and alterations in the ovarian reserve. Thus, this prospective and comparative study aimed to evaluate the association of hypothyroidism with low ovarian reserve. MATERIALS AND METHODS: A subset of 27 patients with primary autoimmune hypothyroidism were compared to healthy women. The ovarian reserve was assessed through the anti-Mullerian hormone (AMH) and the antral follicle count (AFC). RESULTS: Overall, the two groups did not display significant differences in length of their menstrual cycles neither in the AMH serum levels nor the AFC. CONCLUSIONS: No significant alteration was found in the ovarian reserve of women with HT.

Congenital myasthenic syndrome due to DOK7 mutation in a cohort of patients with 'unexplained' limb-girdle muscular weakness.

Congenital myasthenic syndromes (CMS) associated with pathogenic variants in the DOK7 gene (DOK7-CMS) have phenotypic overlap with other neuromuscular disorders associated with limb-girdle muscular weakness (LGMW). Genetic analysis of the most common mutation (c.1124_1127dupTGCC) in DOK7 was performed in 34 patients with "unexplained" LGMW associated with non-specific changes in muscle biopsy. Of the 34 patients, one patient showed the DOK7 c.1124_1127dupTGCC variant in homozygousity. Our study estimates the minimum prevalence of undiagnosed DOK7-CMS to be 2.9% in southern Brazilian patients from our centre. Our data confirm that clinicians should look for DOK7-CMS patients when the clinical manifestation is an 'unexplained' LGMW, mainly if associated with non-specific changes in muscle biopsy.

Early postoperative statin administration does not affect the rate of atrial fibrillation after cardiac surgery.

OBJECTIVES: Postoperative atrial fibrillation is the most frequent complication after cardiac surgery, and the use of statins in preventing them is being extensively studied. The aim of this study was to investigate whether a pause in the administration of statins affects the occurrence of atrial fibrillation after cardiac surgery in a prospective randomized and controlled setting. METHODS: A total of 301 patients without chronic atrial fibrillation with prior statin medication scheduled for elective or urgent cardiac surgery involving the coronary arteries and/or heart valves were prospectively recruited and randomized for statin re-initiation on either the first (immediate statin group) or the fifth (late statin group) postoperative day, using the original medication and dosage. The immediate statin group comprised 146 patients and the late statin group 155 patients. Except for a somewhat higher rate of males (85% vs 73%, P = 0.016) in the immediate statin group, the baseline characteristics and the distribution of procedures performed within the groups were comparable. The occurrence of postoperative atrial fibrillation and the clinical course of the patients were compared between the groups. RESULTS: The incidence of atrial fibrillation was 46% and the median delay after surgery before the onset of atrial fibrillation was 3 days in both groups (P = NS). No differences were observed in the frequency of the arrhythmia in any subgroup analyses or in other major complications or clinical parameters. No adverse effects related to early statin administration were detected. CONCLUSIONS: Early re-initiation of statins does not appear to affect the occurrence of postoperative atrial fibrillation. CLINICAL TRIAL REGISTRATION: European Union Drug Regulating Authorities Clinical Trials Database (EudraCT)-2016-001655-44.

Clinical Pregnancy After Elimination of Embryo Fragments Before Fresh Cleavage-stage Embryo Transfer.

Objective: To determine if the elimination of fragments in cleavage-stage embryos, before fresh transfer, improves pregnancy rates in in vitro fertilization cycles. Materials and methods: This is a Prospective observational case-control study carried out at a University Reproductive Center. We included Twenty-six infertile patients divided into two groups. Group one: 13 patients with embryos classified as grade B and C (embryos with fragments) according to the Hill classification, and Group two: 13 patients with grade A embryos (embryos with no fragments). Embryo Defragmentation was performed in embryos of group one 65 to 68 hours after conventional fertilization. Fresh embryo transfer was made after two hours post fragments removal. Reproductive results were evaluated and compared between both groups. Results: The total number of clinical pregnancies was nine. In group one there were 5 (38.5 %); in group two, there were 4 (30.8%). The difference was not statistically significant (p = 0.68). Two abortions were reported in the study, both in group one; were fragment elimination was performed. This represents an abortion rate of 40% in patients who got pregnant in this group. These patients had twice the probability of suffering an abortion (OR 2.1; 95% CI 1.4-3.37). Ongoing pregnancies were similar in both groups. Conclusion: Removal of fragments in freshly transferred day three embryos could be an alternative to increase clinical pregnancy and ongoing pregnancy rates in patients who have only poor-quality embryos. Despite the relationship with a higher abortion rate, this strategy could represent a real alternative for this type of patient.

The elimination of apoptotic sperm in IVF procedures and its effect on pregnancy rate.

OBJECTIVE: To identify the effect of apoptotic sperm elimination with MACS in patients that require IVF. METHODS: An experimental, cross-sectional, descriptive, prospective and non-blinded study of diagnostic tests performed in patients who required IVF and ICSI from July 2011 to July 2012. Ninety-two couples participated according to the treatment administered to the semen sample; in the control group: the samples were subjected only to density gradients before ICSI, in the study group: the same procedure was performed plus the addition of the MACS technique. Comparing the groups, we assessed the fertilization, division, viable embryos and clinical pregnancy rates in all cases. RESULTS: We found significant differences when using MACS technique in sperm parameters. We found no differences between the total samples of the control and study groups. When separating the own and donated eggs in each group, we found an improvement in the fertilization rates (p<0.001) of the own eggs. In both groups, the handling of donated eggs lead to a significant improvement in the immunological pregnancy test (IPT) and fetal heart rate (FHR) results. Only in the donated eggs group, where MACS was applied, could we see that all cases with positive IPT had a fetal heart rate, which shows a significant difference (p<0.002) when compared with the control group, where the percentage decreased abruptly. CONCLUSIONS: This study demonstrates the effectiveness of the use of annexins (MACS) in eliminating apoptotic sperm, and when the obtained sperm is applied to good-quality eggs.

NOVEL ANALYTICAL STUDY FOR REACTION INTERMEDIATES IN THE PRIMARY RADIATION INTERACTION OF DNA USING A SYNCHROTRON RADIATION-INDUCED LUMINESCENCE SPECTROSCOPY.

To identify the precise molecular processes to induce DNA lesions, we attempt a novel spectroscopy of X-ray induced luminescence (XIL) using soft X-ray synchrotron radiation, which is a non-destructive analysis of the reaction intermediates in the elementary reaction pathway of damage induction and self-organized restoration. Using a liquid micro-jet technique to introduce aqueous samples in a vacuum chamber, we measure UV-visible luminescence from nucleotide solution as a function of the soft X-ray energy from the nitrogen to oxygen K-edge region. The XIL intensities for the nucleotide solutions are significantly enhanced in the soft X-ray region (410-530 eV) which is ascribed to the K-shell excitation/ionization of nitrogen atoms in the nucleobases. Furthermore, the XIL spectra do not show any signature of X-ray absorption near-edge structure (XANES) of the nucleobases. This is because the luminescence intensities collected from the integral area of the micro-jet only reflect the quantum yield of luminescence of the absorbed X-ray into UV-visible light irrespective of the absorption cross sections, i.e. of XANES. Thus the present result is the first evidence of luminescence as a result of X-ray absorption of aqueous nucleotides.

Effects of backpack and double pack loads on postural stability.

Measurement of postural stability is crucial for identifying predictors of performance, determining the efficacy of physical training and rehabilitation techniques and evaluating and preventing injuries, particularly for heavy load carriage in hikers, mountain search and rescue personnel and soldiers. This study investigated the effect of load distribution on postural stability in an upright stance using backpack and double pack loads under conflicting or impaired somatosensory, visual and vestibular conditions. The sensory organisation tests were conducted on 20 young adults before and after a 10-min level walking exercise. Young adults' ability to use inputs from somatosensory and visual systems to maintain postural stability was significantly reduced following a 10-min walking exercise with a heavy backpack (30% of body weight), whereas no significant changes were observed for double pack carriage. Thus, the distribution of heavy loads to the front and back provides superior balance control compared with back-only loading. Practitioner summary: This study investigated the effects of heavy (30% of body weight) load distribution on postural stability after a 10-min walking exercise. Backpack carriage significantly reduced postural stability, whereas there was no significant effect under double pack loads. Distribution of heavy loads on the front-and-back is desirable for superior balance control.

Gender Differences in Energy Expenditure During Walking With Backpack and Double-Pack Loads.

OBJECTIVE: To investigate gender differences in energy expenditure during walking with backpack and double-pack loads. BACKGROUND: Studies have reported that energy expenditure during walking with double-pack loads is lower compared with backpack carriage. However, the effect of gender on energy expenditure while walking with these two load distribution systems has not been investigated. METHOD: Thirty healthy young adults (15 female and 15 male participants) walked on a treadmill with backpack and double-pack loads weighing 30% of their body weight at a speed of 0.89 m/s for 10 min. The energy expenditure in terms of oxygen consumption (VO2) and respiratory exchange ratio (RER) were continuously monitored using a portable gas analyzer throughout each walking exercise. A mixed-design analysis of variance model was adopted to test the effects of gender, pack, and time on VO2 and RER. RESULTS: No time effect was observed on VO2. However, significant gender, pack, and interaction effects were observed. The lowest VO2 was found in female participants under double-pack carriage. No significant gender or pack differences existed in RER. However, RER significantly and incrementally increased in time from the 4th through 6th, 8th, and 10th min. CONCLUSION: This study revealed that heavy double-pack load carriage for healthy young female participants had significantly lower energy expenditure (normalized by the entire system weight, i.e., the participant's weight plus the weight of the pack) than that of the male participants in a 10-min walking exercise. APPLICATION: The findings of this study indicated that healthy young female participants carried a heavy double-pack with less energy cost (normalized by the entire system weight, i.e., the participant's weight plus the weight of the pack) compared with their male counterparts during a 10-min walking exercise.

Outcome and clinical course of EHEC O104 infection in hospitalized patients: A prospective single center study.

OBJECTIVES: Shiga-toxin producing O157:H7 Entero Haemorrhagic E. coli [STEC/EHEC] are the most common cause of Haemolytic Uraemic Syndrome [HUS] related to infectious haemorrhagic colitis. Nearly all recommendations on long term treatment of EHEC infections refer to this strain. The 2011 outbreak in Northern Europe was the first of this dimension to be caused by the serotype O104:H4. We report on the 3.5 year follow up of 61 patients diagnosed with symptomatic EHEC O104:H4 infection in spring 2011. METHODS: Patients with EHEC O104 infection were followed in a monocentric, prospective observational study at four time points: 4, 12, 24 and 36 months. These data include the patients' histories, clinical findings, and complications. RESULTS: Sixty-one patients suffering from EHEC O104:H4 associated enterocolitis participated in the study at the time of hospital discharge. The mean age of patients was 43 ± 2 years, 37 females and 24 males. 48 patients participated in follow up 1 [FU 1], 34 patients in follow up 2 [FU 2], 23 patients in follow up 3 [FU 3] and 18 patients in follow up 4 [FU 4]. Out of 61 patients discharged from the hospital and included in the study, 54 [84%] were examined at least at one additional follow up. Serum creatinine decreased significantly between discharge and FU 1 from 1.3 ± 0.1 mg/dl to 0.7 ± 0.1 mg/dl [p = 0.0045]. From FU 1 until FU 4, no further change in creatinine levels could be observed. The patients need of antihypertensive medications decreased significantly [p = 0.0005] between discharge and FU 1 after four months. From FU 1 until FU 3, 24 months later, no further significant change in antihypertensive treatment was observed. CONCLUSIONS: Our findings suggest that patients free of pathological findings at time of discharge do not need a specific follow up. Patients with persistent health problems at hospital discharge should be clinically monitored over four months to evaluate chronic organ damage. Progressive or new emerging renal damage could not be observed over time in any patient.

Muscle Strength and Poststroke Hemiplegia: A Systematic Review of Muscle Strength Assessment and Muscle Strength Impairment.

OBJECTIVES: To systematically review (1) psychometric properties of criterion isokinetic dynamometry testing of muscle strength in persons with poststroke hemiplegia (PPSH); and (2) literature that compares muscle strength in patients poststroke with that in healthy controls assessed by criterion isokinetic dynamometry. DATA SOURCES: A systematic literature search of 7 databases was performed. STUDY SELECTION: Included studies (1) enrolled participants with definite poststroke hemiplegia according to defined criteria; (2) assessed muscle strength or power by criterion isokinetic dynamometry; (3) had undergone peer review; and (4) were available in English or Danish. DATA EXTRACTION: The psychometric properties of isokinetic dynamometry were reviewed with respect to reliability, validity, and responsiveness. Furthermore, comparisons of strength between paretic, nonparetic, and comparable healthy muscles were reviewed. DATA SYNTHESIS: Twenty studies covering 316 PPSH were included. High intraclass correlation coefficient (ICC) inter- and intrasession reliability was reported for isokinetic dynamometry, which was independent of the tested muscle group, contraction mode, and contraction velocity. Slightly higher ICC values were found for the nonparetic extremity. Standard error of the mean (SEM) values showed that a change of 7% to 20% was required for a real group change to take place for most muscle groups, with the knee extensors showing the smallest SEM% values. The muscle strength of paretic muscles showed deficits when compared with both healthy and nonparetic muscles, independent of muscle group, contraction mode, and contraction velocity. Nonparetic muscles only showed minor strength impairments when compared with healthy muscles. CONCLUSIONS: Criterion isokinetic dynamometry is a reliable test in persons with stroke, generally showing marked reductions in muscle strength of paretic and, to a lesser degree, nonparetic muscles when compared with healthy controls, independent of muscle group, contraction mode, and contraction velocity.

Fatigue in patients with Juvenile Idiopathic Arthritis: relationship to perceived health, physical health, self-efficacy, and participation.

BACKGROUND: Fatigue is common in patients with JIA and affects daily life negatively. We assessed the presence and severity of fatigue in patients with JIA, including factors presumed associated with fatigue (e.g., disease activity, disability, pain, physical activity, exercise capacity, and self-efficacy), and whether fatigue is related to participation in physical education classes, school attendance, and sports frequency. METHODS: The current study used baseline data of 80 patients with JIA (age 8-13) who participated in an intervention aimed at promoting physical activity. Primary outcome measurements were fatigue, assessed using the Pediatric-Quality-of-Life-Inventory (PedsQl)-Fatigue-scale and energy level assessed using a VAS scale. Other outcome measurements were disease activity (VAS Physician Global Assessment Scale), disability (Childhood Health Assessment Questionnaire), physical activity (accelerometer), exercise capacity (Bruce treadmill test), self-efficacy (Childhood Arthritis Self-Efficacy Scale), and participation (self-report). RESULTS: Sixty percent of patients with JIA suffered from daily low-energy levels; 27% suffered from very low-energy levels more than half the week. Low energy levels were best predicted by disability and low physical activity. Fatigue measured with the PEDsQL was higher compared to the control-population. Disability and low self-efficacy were main predictors of fatigue. Self-efficacy was a predictor of fatigue but did not act as moderator. Fatigue was a predictor for sports frequency but not for school attendance. CONCLUSION: Fatigue is a significant problem for JIA patients. Interventions aimed at reducing perceived disability, stimulating physical activity, and enhancing self-efficacy might reduce fatigue and thereby enhance participation. TRIAL REGISTRATION: Trial number ISRCTN92733069.

Addressing Free Radical Oxidation in Acne Vulgaris.

OBJECTIVE: Comparatively little attention has been paid to the role of free radical oxidation in acne vulgaris. Here, using the traditional abnormalities cited for acne, the authors address the role of free radical oxidation throughout the pathogenesis by detailing the chemistry that may contribute to clinical changes. To probe the effects of free radical oxidation and test an antioxidant, they conducted a preliminary study of topically applied vitamin E. METHODS: Seventeen patients with mild-to-moderate acne vulgaris were evaluated over an eight-week period in two private dermatology practices in this open-label study. All patients enrolled were on the same baseline regimen of salicylic acid and benzoyl peroxide. This regimen was then supplemented with topical vitamin E in sunflower seed oil. RESULTS: At the end of the eight-week period, all patients demonstrated clinical improvement, as indicated by a reduction in the number of lesions and global mean difference. A statistically significant reduction was noted as early as Week 2. Enrolled patients also expressed a positive experience due to good tolerability and easy application. CONCLUSION: Although the exact pathogenesis of acne vulgaris remains unknown, the presence of excessive reactive oxygen species can be implicated in each of the major abnormalities involved. This presence, along with the positive results of the authors' preliminary study, demonstrates the need for more exploration on the use of topical antioxidants in limiting free radical oxidation in the acne model. This paper is designed to stimulate academic discussion regarding a new way of thinking about the disease state of acne.