Viability and tissue quality of cartilage flaps from patients with femoroacetabular hip impingement: A matched-control comparison

Background: Chondrolabral damage is commonly observed in patients with cam-type femoroacetabular impingement (FAI). Chondral flap reattachment has recently been proposed as a possible preservation technique. Purpose/Hypothesis: The purpose of this study was to determine the viability and tissue quality of chondral flaps from patients with FAI at the time of arthroscopy. It was hypothesized that chondral flaps from patients with cam lesions of the hip would exhibit less viability and greater tissue degeneration than would those of a matched control group. Study Design: Cohort study; Level of evidence, 2. Methods: Patients with cam-type FAI who were treated with hip arthroscopy between 2014 and 2016 were asked to participate in this study. The cartilage lesions were localized and classified intraoperatively according to Beck classification. A chondral flap (study group) and a cartilage sample (control group) were obtained from each patient for histologic evaluation. Cellular viability and tissue quality were examined and compared in both groups. Cellular viability was determined with live/dead staining, and tissue quality was evaluated using safranin O/fast green, hematoxylin and eosin (H&amp;E) staining, and immunohistochemistry for collagen II. Osteoarthritis Research Society International (OARSI) grading was used for quality assessment, and Image J software was used to calculate the percentage of tissue viability and Col II stain. Results: A total of 10 male patients with a mean age of 38.4 years (range, 30-55 years) were enrolled. All chondral flaps were classified as Beck grade 4. The mean cellular viability of the chondral flaps was reduced (54.6% ± 25.6%), and they were found to be degenerated (OARSI grade, 4 ± 1.27). Control samples also had reduced viability (38.8% ± 30.3%) and were degenerative (OARSI grade, 3.5 ± 1.38). There was no statistically significant intergroup difference for viability ( P = .203) or OARSI grade ( P = .645), nor was there an intragroup correlation between viability and OARSI grade ( P &gt; .05). A significant negative correlation ( r = −0.9, P = .035) was found between OARSI grade and collagen II percentage scale in 5 selected samples. Conclusion: Despite appearing normal macroscopically, the chondral flaps from patients with cam-type FAI displayed loss of viability and tissue degeneration. In addition, control samples obtained away from the injury area also displayed cartilage damage and degeneration. Careful consideration should be taken when attempting to reattach the chondral flap. </jats:sec

Raw material procurement for termite fishing tools by wild chimpanzees in the Issa Valley, Tanzania

Objectives: Chimpanzee termite fishing has been studied for decades, yet the selective processes preceding the manufacture of fishing tools remain largely unexplored. We investigate raw material selection and potential evidence of forward planning in the chimpanzees of Issa valley, western Tanzania. Materials and Methods: Using traditional archaeological methods, we surveyed the location of plants from where chimpanzees sourced raw material to manufacture termite fishing tools, relative to targeted mounds. We measured raw material abundance to test for availability and selection. Statistics included Chi-Squared, two-tailed Wilcoxon, and Kruskall-Wallace tests. Results: Issa chimpanzees manufactured extraction tools only from bark, despite availability of other suitable materials (e.g. twigs), and selected particular plant species as raw material sources, which they often also exploit for food. Most plants were sourced 1–16 m away from the mound, with a maximum of 33 m. The line of sight from the targeted mound was obscured for a quarter of these plants. Discussion: The exclusive use of bark tools despite availability of other suitable materials indicates a possible cultural preference. The fact that Issa chimpanzees select specific plant species and travel some distance to source them suggests some degree of selectivity and, potentially, forward planning. Our results have implications for the reconstruction of early hominin behaviors, particularly with regard to the use of perishable tools that remain archaeologically invisible

Wild capuchin monkeys adjust stone tools according to changing nut properties

Animals foraging in their natural environments need to be proficient at recognizing and responding to changes in food targets that affect accessibility or pose a risk. Wild bearded capuchin monkeys (Sapajus libidinosus) use stone tools to access a variety of nut species, including otherwise inaccessible foods. This study tests whether wild capuchins from Serra da Capivara National Park in Brazil adjust their tool selection when processing cashew (Anacardium spp.) nuts. During the ripening process of cashew nuts, the amount of caustic defensive substance in the nut mesocarp decreases. We conducted field experiments to test whether capuchins adapt their stone hammer selection to changing properties of the target nut, using stones of different weights and two maturation stages of cashew nuts. The results show that although fresh nuts are easier to crack, capuchin monkeys used larger stone tools to open them, which may help the monkeys avoid contact with the caustic hazard in fresh nuts. We demonstrate that capuchin monkeys are actively able to distinguish between the maturation stages within one nut species, and to adapt their foraging behaviour accordingly

Fractal analysis applied to light curves of δ\delta Scuti stars

Fractal behaviour, i.e. scale invariance in spatio-temporal dynamics, have been found to describe and model many systems in nature, in particular fluid mechanics and geophysical related geometrical objects, like the convective boundary layer of cumulus cloud fields, topographic landscapes, solar granulation patterns, and observational astrophysical time series, like light curves of pulsating stars. The main interest in the study of fractal properties in such physical phenomena lies in the close relationships they have with chaotic and turbulent dynamic. In this work we introduce some statistical tools for fractal analysis of light curves: Rescaled Range Analysis (R/S), Multifractal Spectra Analysis, and Coarse Graining Spectral Analysis (CGSA), an FFT based algorithm, which can discriminate in a time series the stochastic fractal power spectra from the harmonic one. An interesting application of fractal analysis in asteroseismology concerns the joint use of all these tools in order to develop classification criteria and algorithms for {\delta}-Scuti pulsating stars. In fact from the fractal and multi-fractal fingerprints in background noise of light curves we could infer on different mechanism of stellar dynamic, among them rotation, modes excitation and magnetic activity.Comment: 13 pages, 10 figure

Identification and antimicrobial susceptibility of Streptomyces and other unusual Actinobacteria clinical isolates in Spain

Two hundred and eighty-six isolates from human clinical samples were identified between 1996 and 2019 as belonging to 8 families, 19 genera and 88 species of Actinobacteria. The most identified genera were Streptomyces (182 strains from 45 species), Actinomadura (29 strains, 5 species), Nocardiopsis (21 strains, 6 species) and Dietzia (18 strains, 5 species). The rest of the identified genera (15) contained 27 species with 36 isolates. Of the species studied, only 13/88 had been documented previously as isolates from clinical samples, and in some cases, as true pathogens. In this sense, a literature review of the species found in infections or in clinical samples without clear involvement in pathology has been carried out. Finally, the susceptibility to 8 antimicrobial agents has been studied. Streptomyces showed high resistance (80.8%) against cefotaxime and cotrimoxazole (55.5%), and no isolate resistance to amikacin and linezolid have been found. Lower percentages of resistance have been found in other genera, except in Dietzia (100% against cotrimoxazole and 44.4% against erythromycin). The greatest resistance in these genera was to cotrimoxazole (29.8) and erythromycin (27,9%), and no resistance to linezolid has been found in these genera. In Microbispora, Nonomuraea and Umezawaea, no resistant isolates have been found against any antibiotic studied. Only 3/104 isolates were resistant to amikacin in Amycolatopsis, Crossiella, and Micromonosopora. One isolate of Amycolatopsis was resistant to imipenem.S

Promoting physical activity at the school playground: A quasi-experimental intervention study

In looking for new strategies to promote physical activity (PA), the purpose of this study was to determine whether providing equipment, playground markings, and a physical education (PE)-based intervention effectively increases PA levels during school recess. A total of 223 children (mean age = 7.10 years ± 0.6; 45.3% female) from three schools participated in this study in 2012. In the first intervention school (G1; n = 75) six previous PE classes teaching games for recess were performed and playground markings and game equipment were provided. In the second intervention school (G2; n = 68) only playground markings and game equipment were provided. The third school served as the control group (GC; n = 80). PA was assessed with pedometers. The increase in mean steps after intervention in G2 was higher than the G1 and GC (P < 0.001). No differences between G1 and GC were observed at post-intervention (P = 0.05). The effects did not vary by gender or BMI. Providing game equipment and playground marks may increase children PA in recess. Nevertheless, additional PE-based intervention did not imply an improvement, and was not effective in increasing PA