Miracle-dz/UniFAR-FTUs huggingface dataset:
Patellofemoral Pressure Changes After Static and Dynamic Medial Patellofemoral Ligament Reconstructions

Background: Reconstructing the medial patellofemoral ligament (MPFL) has become a key procedure for stabilizing the patella. Different techniques to reconstruct the MPFL have been described: static techniques in which the graft is fixed rigidly to the bone or dynamic techniques with soft tissue fixation. Static MPFL reconstruction is most commonly used. However, dynamic reconstruction deforms more easily and presumably functions more like the native MPFL. Purpose/Hypothesis: The aim of the study was to evaluate the effect of the different MPFL fixation techniques on patellofemoral pressures compared with the native situation. The hypothesis was that dynamic reconstruction would result in patellofemoral pressures closer to those generated in an intact knee. Study Design: Controlled laboratory study. Methods: Seven fresh-frozen knee specimens were tested in an in vitro knee joint loading apparatus. Tekscan pressure-sensitive films fixed to the retropatellar cartilage measured mean patellofemoral and peak pressures, contact area, and location of the center of force (COF) at fixed flexion angles from 0° to 110°. Four different conditions were tested: intact, dynamic, partial dynamic, and static MPFL reconstruction. Data were analyzed using linear mixed models. Results: Static MPFL reconstruction resulted in higher peak and mean pressures from 60° to 110° of flexion (P < .001). There were no differences in pressure between the 2 different dynamic reconstructions and the intact situation (P > .05). The COF in the static reconstruction group moved more medially on the patella from 50° to 110° of flexion compared with the other conditions. The contact area showed no significant differences between the test conditions. Conclusion: After static MPFL reconstruction, the patellofemoral pressures in flexion angles from 60° to 110° were 3 to 5 times higher than those in the intact situation. The pressures after dynamic MPFL reconstruction were similar as compared with those in the intact situation, and therefore, dynamic MPFL reconstruction could be a safer option than static reconstruction for stabilizing the patella. Clinical Relevance: This study showed that static MPFL reconstruction results in higher patellofemoral pressures and thus enhances the chance of osteoarthritis in the long term, while dynamic reconstruction results in more normal pressures.
Precision Medicine in Pediatric Neurooncology: A Review

Central nervous system tumors are the leading cause of cancer related death in children. Despite much progress in the field of pediatric neurooncology, modern combination treatment regimens often result in significant late effects, such as neurocognitive deficits, endocrine dysfunction, secondary malignancies, and a host of other chronic health problems. Precision medicine strategies applied to pediatric neurooncology target specific characteristics of individual patients' tumors to achieve maximal killing of neoplastic cells while minimizing unwanted adverse effects. Here, we review emerging trends and the current literature that have guided the development of new molecularly based classification schemas, promising diagnostic techniques, targeted therapies, and delivery platforms for the treatment of pediatric central nervous system tumors.
Retrieval Practice Produces More Learning than Elaborative Studying with Concept Mapping

Two different ways of thinking through texts are compared for learning value. Educators rely heavily on learning activities that encourage elaborative studying, whereas activities that require students to practice retrieving and reconstructing knowledge are used less frequently. Here, we show that practicing retrieval produces greater gains in meaningful learning than elaborative studying with concept mapping. The advantage of retrieval practice generalized across texts identical to those commonly found in science education. The advantage of retrieval practice was observed with test questions that assessed comprehension and required students to make inferences. The advantage of retrieval practice occurred even when the criterial test involved creating concept maps. Our findings support the theory that retrieval practice enhances learning by retrieval-specific mechanisms rather than by elaborative study processes. Retrieval practice is an effective tool to promote conceptual learning about science.
Gamma-Ray Flares from the Crab Nebula

Gamma-ray observations of the Crab Nebula by two different space telescopes challenge particle acceleration theory. A young and energetic pulsar powers the well-known Crab Nebula. Here, we describe two separate gamma-ray (photon energy greater than 100 mega–electron volts) flares from this source detected by the Large Area Telescope on board the Fermi Gamma-ray Space Telescope. The first flare occurred in February 2009 and lasted approximately 16 days. The second flare was detected in September 2010 and lasted approximately 4 days. During these outbursts, the gamma-ray flux from the nebula increased by factors of four and six, respectively. The brevity of the flares implies that the gamma rays were emitted via synchrotron radiation from peta–electron-volt (1015 electron volts) electrons in a region smaller than 1.4 × 10−2 parsecs. These are the highest-energy particles that can be associated with a discrete astronomical source, and they pose challenges to particle acceleration theory.
Three-Dimensional Plasmon Rulers

The optical response of a fabricated nanostructure can be used to determine distances in three dimensions. Plasmon rulers can be used to determine nanoscale distances within chemical or biological species. They are based on the spectral shift of the scattering spectrum when two plasmonic nanoparticles approach one another. However, the one-dimensionality of current plasmon rulers hampers the comprehensive understanding of many intriguing processes in soft matter, which take place in three dimensions. We demonstrated a three-dimensional plasmon ruler that is based on coupled plasmonic oligomers in combination with high-resolution plasmon spectroscopy. This enables retrieval of the complete spatial configuration of complex macromolecular and biological processes as well as their dynamic evolution.
Radiographic Reference Points Are Inaccurate With and Without a True Lateral Radiograph

Background: Studies have reported methods for radiographically delineating medial patellofemoral ligament (MPFL) femoral tunnel position on a true lateral knee radiograph. However, obtaining a true lateral fluoroscopic radiograph intraoperatively can be challenging, rendering radiographic methods for tunnel positioning potentially inaccurate. Purpose: To quantify the magnitude of MPFL femoral tunnel malposition that occurs on true lateral and aberrant lateral knee radiographs when using a previously reported radiographic technique for MPFL femoral tunnel localization. Study Design: Descriptive laboratory study. Methods: Ten fresh-frozen cadaveric knees were dissected to expose the MPFL femoral insertion and surrounding medial knee anatomy. True lateral and aberrant lateral knee radiographs at 2.5°, 5°, and 10° off-axis were obtained with a standard mini C-arm in 4 orientations: anterior to posterior, posterior to anterior, caudal, and cephalad. A previously reported radiographic method for MPFL femoral localization was performed on all radiographs and compared in reference to the anatomic MPFL attachment center. Results: The radiographic point, as previously described, was a mean distance of 4.1 mm from the anatomic MPFL attachment on a true lateral knee radiograph. The distance between the anatomic MPFL attachment center and the radiographic point significantly increased on aberrant lateral knee radiographs with as little as 5° of rotational error in 3 of 4 orientations of rotation when a standard mini C-arm was used. This corresponded to a malposition of 7.5, 9.2, and 8.1 mm on 5°-aberrant radiographs in the anterior-posterior, posterior-anterior, and cephalad orientations, respectively (P < .005). In the same 3 orientations of rotation, MPFL tunnel malposition on the femur exceeded 5 mm on 2.5° aberrant radiographs. Conclusion: The commonly utilized radiographic point, as previously described for MPFL femoral tunnel placement, results in inaccurate tunnel localization on a true lateral radiograph, and this inaccuracy is perpetuated with aberrant radiography. Aberrant lateral knee imaging of as little as 5° off-axis from true lateral has a significant effect on placement of a commonly used radiographic point relative to the anatomic MPFL femoral attachment center and results in nonanatomic MPFL tunnel placement. Clinical Relevance: This study demonstrates that radiographic localization of the MPFL femoral tunnel results in inaccurate tunnel placement on a true lateral radiograph, particularly when there is deviation from a true lateral fluoroscopic image, which can be difficult to obtain intraoperatively. Assessing anatomy directly intraoperatively, rather than relying solely on radiographs, may help avoid MPFL tunnel malposition.
Depression Symptomatology and Anterior Cruciate Ligament Injury

Background: Recent literature has recognized a correlation with depression and poor self-reported functional outcome after orthopaedic procedures. However, the effect of depression on anterior cruciate ligament reconstruction (ACLR) outcome has never been studied. Purpose: To quantify the incidence of major depressive disorder (MDD) and correlate depression symptoms with patient-rated knee function in patients undergoing ACLR. Study Design: Cohort study; Level of evidence, 2. Methods: In this multicenter prospective cohort study, 64 consecutive adult patients undergoing primary ACLR were given the 16-item self-report Quick Inventory of Depressive Symptomatology (QIDS) to assess MDD symptoms preoperatively and at 6 weeks, 12 weeks, 24 weeks, and 1 year postoperatively. Lysholm and International Knee Documentation Committee (IKDC) subjective scores were obtained at the same time points to assess self-reported knee function. A QIDS score ≥6 served as a validated threshold for diagnosis of MDD. MDD and non-MDD group assignment was based on preoperative QIDS score. Student t test analysis was performed to compare ACLR outcomes between MDD and non-MDD patients. Correlation among QIDS, Lysholm, and IKDC scores was determined with Spearman r value. Results: A total of 27 patients (42%) were categorized in the MDD group. At baseline, the MDD group reported mean Lysholm (50.8) and IKDC (43.7) scores that were significantly lower than those (64.9 and 57.0, respectively) reported by the non-MDD group (P < .05). Both cohorts showed similar and significant absolute improvement from baseline to 1 year postoperatively (MDD vs non-MDD, increase in mean Lysholm: +24.4 vs +23.5 [P = .63]; MDD vs non-MDD, increase in mean IKDC: +28.1 vs +32.3 [P = .21]). While Lysholm and IKDC scores improved in both groups, at 1-year follow-up, MDD patients reported significantly lower mean Lysholm (75.2 vs 88.4; P = .04) and mean IKDC (71.8 vs 89.3; P = .001) scores as compared with their non-MDD counterparts. In addition, a moderate inverse correlation was found between QIDS and Lysholm scores (r = −0.50) and between QIDS and IKDC scores (r = −0.54). Interestingly, 4 patients experienced complications in the MDD cohort (15%), while there were no complications in the non-MDD group. Conclusion: This study suggests that ACLR may be an equally effective intervention for MDD and non-MDD patients, given their similar significant absolute improvements in functional scores from baseline to 1 year after ACLR. However, MDD patients still reported significantly lower self-reported functional scores at baseline and 1 year postoperatively.
Greater Mechanical Loading During Walking Is Associated With Less Collagen Turnover in Individuals With Anterior Cruciate Ligament Reconstruction

Background: Individuals who have sustained an anterior cruciate ligament (ACL) injury and undergo ACL reconstruction (ACLR) are at higher risk of developing knee osteoarthritis. It is hypothesized that altered knee loading may influence the underlying joint metabolism and hasten development of posttraumatic knee osteoarthritis. Purpose: To explore the associations between serum biomarkers of cartilage metabolism and peak vertical ground-reaction force (vGRF) and vGRF loading rate in the injured and uninjured limbs of individuals with ACLR. Study Design: Descriptive laboratory study. Methods: Patients with a history of a primary unilateral ACLR who had returned to unrestricted physical activity (N = 19) participated in the study. Resting blood was collected from each participant before completing 5 walking gait trials at a self-selected comfortable speed. Peak vGRF was extracted for both limbs during the first 50% of the stance phase of gait, and the linear vGRF loading rate was determined between heel strike and peak vGRF. Sera were assessed for collagen breakdown (collagen type II cleavage product [C2C]) and synthesis (collagen type II C-propeptide [CPII]), as well as aggrecan concentrations, via commercially available specific enzyme-linked immunosorbent assays. Pearson product-moment correlations (r) and Spearman rank-order correlations (ρ) were used to evaluate associations between loading characteristics and biomarkers of cartilage metabolism. Results: Lower C2C:CPII ratios were associated with higher peak vGRF in the injured limb (ρ = −0.59, uncorrected P = .007). There were no significant associations between peak vGRF or linear vGRF loading rate and CPII, C2C, or aggrecan serum concentrations. Conclusion: Lower C2C:CPII ratios were associated with higher peak vGRF in the ACLR limb during gait, suggesting that higher peak loading in the ACLR limb is related to lower type II collagen breakdown relative to type II collagen synthesis. Clinical Relevance: These data suggest that type II collagen synthesis may be higher relative to the amount of type II collagen breakdown in the ACLR limb with higher lower extremity loading. Future study should determine if metabolic compensations to increase collagen synthesis may affect the risk of developing osteoarthritis after ACLR.
A Packing Mechanism for Nucleosome Organization Reconstituted Across a Eukaryotic Genome

Genome-wide nucleosome positioning is a self-organizing system amenable to in vitro reconstitution. Near the 5′ end of most eukaryotic genes, nucleosomes form highly regular arrays that begin at canonical distances from the transcriptional start site. Determinants of this and other aspects of genomic nucleosome organization have been ascribed to statistical positioning, intrinsically DNA-encoded positioning, or some aspect of transcription initiation. Here, we provide evidence for a different explanation. Biochemical reconstitution of proper nucleosome positioning, spacing, and occupancy levels was achieved across the 5′ ends of most yeast genes by adenosine triphosphate–dependent trans-acting factors. These transcription-independent activities override DNA-intrinsic positioning and maintain uniform spacing at the 5′ ends of genes even at low nucleosome densities. Thus, an active, nonstatistical nucleosome packing mechanism creates chromatin organizing centers at the 5′ ends of genes where important regulatory elements reside.
Is Sport Activity Possible After Arthroscopic Meniscal Allograft Transplantation?

Background: Meniscal allograft transplantation (MAT) has produced good to excellent results in the general population; however, few investigations have examined MAT in athletes and sport-related outcomes. Purpose: To report midterm clinical outcomes of MAT and the rate of return to sport in a physically active population. Study Design: Case series; Level of evidence, 4. Methods: The study included all physically active patients who underwent arthroscopic MAT without bone plugs and had a minimum of 2 years of follow-up at a single institution. Clinical evaluation was performed with the Knee injury and Osteoarthritis Outcome Score (KOOS), the Tegner activity scale, and a 0- to 100-point subjective scale for knee function and satisfaction. Outcomes evaluated included ability to return to sport, time to return to sport, level of sport activity upon return compared with preinjury level, and level of decrease in sport participation or reasons for not returning to sport participation. Comparisons were made between patients who did or did not return to sport and between patients who returned to the same level or a decreased level. Regression analysis was performed to determine the variables affecting the outcomes. Results: Eighty-nine patients, whose mean ± SD age at surgery was 38.5 ± 11.2 years, were evaluated to a mean follow-up of 4.2 ± 1.9 years. Total KOOS improved from a mean ± SD of 39.5 ± 18.5 preoperatively to 84.7 ± 14.8 at the latest follow-up (P < .001). The Tegner score improved significantly from a median of 2 (interquartile range [IQR], 1-4) preoperatively to a median of 4 (IQR, 3-6) at the latest follow-up (P < .001), although it did not reach the preinjury level of 6 (IQR, 5-7) (P < .001). Older age at surgery was correlated with the worst clinical results. Sixty-six patients (74%) were able to return to sport after 8.6 ± 4.1 months. Forty-four (49%) returned to the same level as preinjury. Patients who did not return to sport activity and those who reduced their activity level at follow-up had inferior subjective outcomes compared with those who returned to sport and those who returned to their preinjury levels, respectively. Only 11 patients (12%) underwent a surgical procedure during the follow-up period. Conclusion: Arthroscopic MAT without bone plugs improved knee function and reduced pain, allowing sport resumption in 74% of patients and return to the preinjury activity level in 49% of patients at midterm follow-up. Of all the demographic and surgical variables, only age at surgery seemed to affect outcomes.
Prospective Use of a Standardized Nonoperative Early Weightbearing Protocol for Achilles Tendon Rupture

Background: Acute traumatic rupture of the Achilles tendon can be treated operatively or nonoperatively. Throughout the literature, there is no consensus regarding the optimal treatment protocol. Purpose: To report on 17 years of experience with treating this injury with a standardized nonoperative treatment protocol. Study Design: Case Series; Level of evidence, 4. Methods: The treatment protocol was based on a combination of an equinus cast and rehabilitation boot, which promoted immediate full weightbearing and early functional rehabilitation. A total of 171 patients were consecutively treated and prospectively followed from 1996 to 2013. Assessed were subjective parameters such as pain, loss of strength, return to previous activity level, meteosensitivity, and general satisfaction with the treatment outcome. Clinical assessment included testing of plantar flexion strength and endurance, calf circumference, and tendon length. Subjective and clinical parameters were then used to calculate a modified Thermann score. The correlation between tendon lengthening and function was calculated using the Pearson correlation coefficient. Results: A total of 114 patients were followed for a minimum of 12 months (mean, 27 ± 20 months; range, 12-88 months). The mean Thermann score was 82 ± 13 (range, 41-100), and subjective satisfaction was rated “very good” and “good” in 90%. An inverse correlation was found between tendon length and muscle strength (R = −0.3). There were 11 reruptures (8 with and 3 without an adequate trauma). General complications were 5 deep venous thromboses, 1 complex regional pain syndrome, and minor problems such as transient heel pain (n = 3), heel numbness (n = 1), and cast-associated skin abrasions (n = 4). Conclusion: Seventeen years of experience with a nonoperative treatment protocol for acute rupture of the Achilles tendon confirmed good functional outcome and patient satisfaction. Reruptures mostly occurred with new traumatic events in the vulnerable phase from 6 to 12 weeks after the initial injury. Muscle strength correlated to tendon length, making its assessment a crucial follow-up parameter. The protective equinus cast and boot can protect against excessive tendon lengthening during the healing process.
Polarized Gamma-Ray Emission from the Galactic Black Hole Cygnus X-1

This gamma-ray emission originates from a jet of relativistic particles that is formed in close proximity to the black hole. Because of their inherently high flux allowing the detection of clear signals, black hole x-ray binaries are interesting candidates for polarization studies, even if no polarization signals have been observed from them before. Such measurements would provide further detailed insight into these sources’ emission mechanisms. We measured the polarization of the gamma-ray emission from the black hole binary system Cygnus X-1 with the International Gamma-Ray Astrophysics Laboratory Imager on Board the Integral Satellite (INTEGRAL/IBIS) telescope. Spectral modeling of the data reveals two emission mechanisms: The 250- to 400-keV (kilo–electron volt) data are consistent with emission dominated by Compton scattering on thermal electrons and are weakly polarized. The second spectral component seen in the 400-keV to 2-MeV band is by contrast strongly polarized, revealing that the MeV emission is probably related to the jet first detected in the radio band.
Tendências em dez anos das condições de saúde de idosos brasileiros: evidências da Pesquisa Nacional por Amostra de Domicílios (1998, 2003, 2008)

Data from a representative national household survey were used to examine 10-year trends (1998-2008) in health conditions of Brazilian elderly. A random sample of 105,254 individuals aged > 60 years participated. The mean age was 69 years and 56% were women. There was a gradual increase in the prevalence of good or excellent self-rated health (39.3%, 43.5% and 45.0%, in 1998, 2003 and 2008, respectively) and a decrease in self-reported arthritis, heart disease, and depression. The prevalence of self-reported hypertension (43.9%, 48.8%, and 53.3%, respectively) and diabetes (10.3%, 13.0% and 16.1% respectively) increased sharply. The prevalence of inability to perform activities of daily living (eating, bathing or using the toilet) remained stable (6.5%, 6.4% and 6.9%, respectively). The achievement of three or more physician visits over the previous 12 months increased by 21% from 1998 to 2008. Hospitalization decreased by 10% in the corresponding period. The above mentioned trends persisted after adjustments for age and sex. The results showed improvements in some health dimensions of the elderly, but not all. Changes in the use of health services occurred as expected with the expansion of primary healthcare activities in Brazil.
Comparative toxicity of bentazon and molinate on growth, photosynthetic pigments, photosynthesis, and respiration of the Portuguese ricefield cyanobacterium Nostoc muscorum

Bentazon and molinate are selective herbicides recommended for integrated weed management in rice. Their toxicity on growth and some biochemical and physiological parameters of Nostoc muscorum, an abundant cyanobacterium in Portuguese rice fields, was evaluated under laboratory conditions during time‐ and concentration‐dependent exposure for 72 h. Results showed that toxic concentrations (0.75–2 mM) of both herbicides have pleiotropic effects on the cyanobacterium. Molinate was more toxic than bentazon to growth, respiration, chlorophyll‐a, carotenoids, and phycobiliproteins contents. Protein content was increased by both herbicides although the effect was particularly evident with higher concentrations of molinate (1.5–2 mM). The herbicides had contrasting effects on carbohydrates content: molinate increased this organic fraction whereas bentazon decreased it. Photosynthesis and respiration were inhibited by both herbicides. © 2009 Wiley Periodicals, Inc. Environ Toxicol, 2010.