Biomechanical factors associated with patellofemoral pain in children and adolescents.

To investigate the biomechanical factors associated with patellofemoral pain in children and adolescents. A cross-sectional, population-based study conducted in Brazil from 2019 to 2023, involving students from public schools. Adjusted prevalence ratios and their respective 95% confidence intervals for the outcome in relation to independent variables were calculated for association analysis, adopting a significance level of 5%. Out of the total of 283 students, 152 were female and 182 were aged between 16 and 18 years old. A positive association was observed between the presence of patellofemoral pain and a poor movement quality in both lower limbs (right side: p = 0.04 and left side: p = 0.04) as well as with dynamic valgus of the left lower limb (p < 0.01). Patellofemoral pain in children and adolescents is associated with poor movement quality in the lower limbs and dynamic valgus of the left lower limb. Actions targeting these biomechanical factors may be crucial for early diagnosis and clinical treatment of this disfunction.

Passivation-Free, Liquid-Metal-Based Electrosynthesis of Aluminum Metal-Organic Frameworks Mediated by Light Metal Activation.

The production of aluminum (Al) metal-organic frameworks (MOFs) by electrosynthesis using solid-state Al electrodes always faces significant challenges due to the formation of a passivating aluminum oxide layer in the process. Here, we developed a liquid-metal-based method to electrosynthesize an aluminum Al-MOF (MIL-53). This method uses a liquid-state gallium (Ga) anode as a reservoir and activator for a light metal, Al, in the form of Al-Ga alloys that releases Al3+ for the electrosynthesis of Al-MOFs. Introducing Ga into the system inhibits the formation of aluminum oxide passivation layer and promotes the electrochemical reaction for Al-MOF synthesis. The electrosynthesis using liquid Al-Ga alloy is conducted at ambient temperatures for long durations without requiring pretreatment for aluminum oxide removal. We show that the Al-MOF products synthesized from 0.40 wt % Al in liquid Ga lead to the highest crystallinity and possess a specific surface area greater than 800 m2 g-1 and a low capacity for CO2 adsorption that can be used as a potential matrix for CO2/N2 separation. This work provides evidence that employing liquid-metal electrodes offers a viable pathway to circumvent surface passivation effects that inevitably occur when using conventional solid metals. It also introduces an efficient electrosynthesis method based on liquid metals for producing atomically porous materials.

Gap fluctuations, Cooper pairs with finite center-of-mass momentum, and suppression of superconductivity in inhomogeneous systems with dopant superpuddles agglomerates.

Spatially extended aggregates or clusters of dopants are ubiquitous in a plethora of granular superconducting systems, such as Al-dopedMgB2and N-dopedMo2N, forming a droplet network that is very important to their characterization and to the description of their superconducting properties. At the same time, one of the most studied classes of unconventional superconducting materials are the high-temperature superconductors, where special attention is given to the hole-doped cuprates, where the carrier concentration is controlled by the amount of extra interstitial oxygen dopants. In this context, the formation of spatially inhomogeneous aggregates of interstitial dopant oxygen atoms, in the form of nanosized superpuddles, is not only relevant, but also a subject of intense recent experimental and theoretical surveys. Following these efforts, in this work we investigate the consequences of the presence of networks of inhomogeneously distributed dopant superpuddles on the superconducting state. Starting from the inhomogeneous extended disordered background brought by the network of superpuddles, we demonstrate, with the aid of an effective interaction between electrons mediated by the local vibrational degrees of freedom of each puddle, that the Cooper pairs arising from an attractive interaction in an inhomogeneous medium have a finite center-of-mass (CM) momentum,p, that breaks up the Cooper channel. Furthermore, we derive an analytical expression for the amplitude of the superconducting gap,Δk, in terms of disorder and finite CM momentum and show that amplitude fluctuations are induced in the superconducting state by the presence of the superpuddles, where both the gap and the critical temperature are reduced by disorder and finite momentum pairs. Finally, we discuss our findings in the context of synchronized networks of superconducting oxygen nano-puddles in cuprates and in other granular superconducting systems.

3D Printing of Monoliths Using TIFSIX-Ni-Based Formulations for the Electric Swing Adsorption of CO2.

The hybrid ultraporous material TIFSIX-Ni ([Ni(pyrazine)2(TiF6)]n) was incorporated into a composite ink for the first time for the three-dimensional (3D) printing of monoliths. The large-scale synthesis of TIFSIX-Ni was completed using two different Ni(II) salts, with CO2 uptakes of 1.90 mmol g-1 achieved using mechanochemically assisted thermal synthesis. The monoliths were then tested for the capture and release of CO2 gas using electric swing adsorption (ESA) under dry and humid conditions. A working capacity of 1.7% was achieved (comparing dynamic data with isotherm data) when a current of 2.1 A was applied for 10 min. The monolith could be cycled repeatedly for 6 h without impacting the performance of the material or loss of capacity. Part of this work explored the improvement of mechanochemically assisted synthetic methods of TIFISX-Ni in reducing the costs associated with large-scale production, allowing for improvements in the overall scale-up and processability of the material for industrial applications.

Tunable Polymer Nanoreactors from RAFT Polymerization-Induced Self-Assembly: Fabrication of Nanostructured Carbon-Coated Anatase as Battery Anode Materials with Variable Morphology and Porosity.

We demonstrate a modular synthesis approach to yield mesoporous carbon-coated anatase (denoted as TiO2/C) nanostructures. Combining polymerization-induced self-assembly (PISA) and reversible addition-fragmentation chain-transfer (RAFT) dispersion polymerization enabled the fabrication of uniform core-shell polymeric nanoreactors with tunable morphologies. The nanoreactors comprised of a poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) shell and a poly(benzyl methacrylate) (PBzMA) core. We selected worm-like and vesicular morphologies to guide the nanostructuring of a TiO2 precursor, namely, titanium(IV) bis(ammonium lactato)dihydroxide (TALH). Subsequent carbonization yielded nanocrystalline anatase and simultaneously introduced a porous carbon framework, which also suppressed the crystal growth (∼5 nm crystallites). The as-prepared TiO2/C materials comprised of a porous structure, with large specific surface areas (>85 m2/g) and various carbon contents (20-30 wt %). As anode components in lithium-ion batteries, our TiO2/C nanomaterials improved the cycling stability, facilitated high overall capacities, and minimized the capacity loss compared to both their sans carbon and commercial anatase analogues.

The electrochemical reduction of a flexible Mn(II) salen-based metal-organic framework.

A new metal-organic framework (MOF) containing a Mn(II) salen complex (BET surface area = 967 ± 6 m2 g-1) undergoes a reversible crystalline-to-amorphous transformation. Experimental studies and computational calculations show that the MOF is stable to a one-electron reduction at more anodic potentials than the corresponding discrete complex.

A cofacial metal-organic framework based photocathode for carbon dioxide reduction.

Innovative and robust photosensitisation materials play a cardinal role in advancing the combined effort towards efficient solar energy harvesting. Here, we demonstrate the photocathode functionality of a Metal-Organic Framework (MOF) featuring cofacial pairs of photo- and electro-active 1,4,5,8-naphthalenediimide (NDI) ligands, which was successfully applied to markedly reduce the overpotential required for CO2 reduction to CO by a well-known rhenium molecular electrocatalyst. Reduction of [Cd(DPNDI)(TDC)] n (DPNDI = N,N'-di(4-pyridyl)-1,4,5,8-naphthalenediimide, H2TDC = thiophene-2,5-dicarboxylic acid) to its mixed-valence state induces through-space Intervalence Charge Transfer (IVCT) within cofacial DPNDI units. Irradiation of the mixed-valence MOF in the visible region generates a DPNDI photoexcited radical monoanion state, which is stabilised as a persistent species by the inherent IVCT interactions and has been rationalised using Density Functional Theory (DFT). This photoexcited radical monoanion state was able to undergo charge transfer (CT) reduction of the rhenium molecular electrocatalyst to effect CO generation at a lower overpotential than that required by the discrete electrocatalyst itself. The exploitation of cofacial MOFs opens new directions for the design philosophy behind light harvesting materials.

Invasive Cardiomechanics During Transcatheter Edge-to-Edge Repair for Massive Tricuspid Regurgitation Using Biventricular Pressure-Volume Loop Monitoring.

Invasive pressure-volume loop analysis allows direct monitoring of changing intraventricular cardiac mechanics during structural heart interventions. Our aim was to illustrate changes in right and left ventricular mechanics during transcatheter edge-to-edge tricuspid repair for severe tricuspid regurgitation. (Level of Difficulty: Advanced.).

Early Impact of the COVID-19 Pandemic on Congenital Heart Surgery Programs Across the World: Assessment by a Global Multi-Societal Consortium.

The coronavirus disease 2019 (COVID-19) pandemic currently gripping the globe is impacting the entire health care system with rapidly escalating morbidities and mortality. Although the infectious risk to the pediatric population appears low, the effects on children with congenital heart disease (CHD) remain poorly understood. The closure of congenital heart surgery programs worldwide to address the growing number of infected individuals could have an unintended impact on future health for COVID-19-negative patients with CHD. Pediatric and congenital heart surgeons, given their small numbers and close relationships, are uniquely positioned to collectively assess the impact of the pandemic on surgical practice and care of children with CHD. We present the results of an international survey sent to pediatric and congenital heart surgeons characterizing the early impact of COVID-19 on the care of patients with CHD.

Enzyme Encapsulation in a Porous Hydrogen-Bonded Organic Framework.

Protection of biological assemblies is critical to applications in biotechnology, increasing the durability of enzymes in biocatalysis or potentially stabilizing biotherapeutics during transport and use. Here we show that a porous hydrogen-bonded organic framework (HOF) constructed from water-soluble tetra-amidinium (1·Cl4) and tetracarboxylate (2) building blocks can encapsulate and stabilize biomolecules to elevated temperature, proteolytic and denaturing agents, and extend the operable pH range for catalase activity. The HOF, which readily retains water within its framework structure, can also protect and retain the activity of enzymes such as alcohol oxidase, that are inactive when encapsulated within zeolitic imidazolate framework (ZIF) materials. Such HOF coatings could provide valid alternative materials to ZIFs: they are metal free, possess larger pore apertures, and are stable over a wider, more biologically relevant pH range.

The spectroelectrochemical behaviour of redox-active manganese salen complexes.

Salens are well-known for their ability to catalyse electrochemical transformations; however, despite their rich history, the fundamental reduction chemistry of these systems remains relatively unexplored. This work reports the design and synthesis of eight discrete, functionalised Mn(iii) pyridyl salen metal complexes, in which the diamine is varied. The electrochemical properties of the complexes were examined using cyclic voltammetry (CV), spectroelectrochemical (SEC) techniques and Density Functional Theory (DFT) computational modelling to explore the mechanisms that underly Mn salen reduction chemistry. We briefly examine the electrochemistry of these complexes in the presence of CO2. These complexes represent potential ligands for incorporation into both discrete and extended metallosupramolecular assemblies.

Enhanced Activity of Enzymes Encapsulated in Hydrophilic Metal-Organic Frameworks.

Encapsulation of biomacromolecules in metal-organic frameworks (MOFs) can preserve biological functionality in harsh environments. Despite the success of this approach, termed biomimietic mineralization, limited consideration has been given to the chemistry of the MOF coating. Here, we show that enzymes encapsulated within hydrophilic MAF-7 or ZIF-90 retain enzymatic activity upon encapsulation and when exposed to high temperatures, denaturing or proteolytic agents, and organic solvents, whereas hydrophobic ZIF-8 affords inactive catalase and negligible protection to urease.

Electroactive Co(iii) salen metal complexes and the electrophoretic deposition of their porous organic polymers onto glassy carbon.

This paper reports the CO2 electroreduction properties of three bis-bromo Co(iii) salen metal complexes and their Porous Organic Polymers (POPs) as a platform for using the salen core as a multi-electron reducing agent. Although Co(iii) salen metal complexes have been studied extensively for their chemical catalysis with CO2, their electrochemical behaviour, particularly their reduction, in the presence of CO2 is much less explored. The discrete Co(iii) complexes enabled the reduction of CO2 to CO in faradaic efficiencies of up to 20%. The reductive electrochemical processes of Co(iii) salen complexes are relatively unknown; therefore, the mechanism of reduction for the complexes was investigated using IR and UV-Vis-NIR spectroelectrochemical (SEC) techniques. The discrete bis-bromo salen complexes were incorporated into POPs with tris-(p-ethynyl)-triphenylamine as a co-ligand and were characterised using solid state NMR, IR, UV-Vis-NIR and Field Emission Scanning Electron Microscopy (FE-SEM). The POP materials were electrophoretically deposited onto glassy carbon under milder conditions than those previously reported in the literature. Direct attachment of the POP materials to glassy carbon enabled improved solid state electrochemical analysis of the samples. The POP materials were also analysed via SEC techniques, where a Co(ii/i) process could be observed, but further reductions associated with the imine reduction compromised the stability of the POPs.

Impact of immunohistochemistry in sentinel lymph node biopsy in head and neck cancer.

To determine the sensitivity, specificity, negative predictive value (NPV) and accuracy of hematoxylin-eosin (HE) staining compared to immunohistochemistry (IHC) in sentinel lymph node (SLN) histological analyses of head and neck squamous cell carcinoma. The Clinical prospective study was carried out at Tertiary referral university hospital. Patients with oral, lip and oropharyngeal squamous cell carcinoma undergoing elective neck dissection with clinically and radiologically negative necks were included. All patients were submitted to computer tomography scan for the evaluation of lymphatic metastases. The surgical procedure consisted of tumor resection, SLN sampling and elective neck dissection. Negative SLNs via HE were then submitted for IHC analysis of cytokeratin AE1/AE3 and step serial section (SSS). The main outcome measures were the negative predictive value of conventional HE staining techniques in the diagnosis of lymphatic metastases with the SSS/IHC analysis. Of 46 patients undergoing 63 neck procedures, 53 were SLN negative and 10 were positive on HE analysis. Using SSS/IHC analysis of these 53 negative SLNs on HE, two (3.8 %) were found to be positive. For HE, the sensitivity, specificity, NPV and accuracy were 77, 100, 94, and 95 %, respectively. With subsequent analysis with SSS/IHC, these values increased to 92, 100, 98 and 98 %, respectively. SSS/IHC is important in SLN analysis as the false negative rate decreased significantly while increasing the inherent sensitivity of the analyses.

Bacterial translocation as a source of Dacron-graft contamination in experimental aortic operation: the importance of controlling SIRS.

BACKGROUND: Several experimental studies have shown the beneficial effects of nitric oxide (NO) in the modulation of the systemic inflammatory response syndrome (SIRS). Nitric oxide is involved in and affects almost all stages in the development of inflammation. We have attempted to ascertain whether the nitric oxide donor molsidomine prevents aortic graft contamination through control of the SIRS and a decrease in bacterial translocation (BT). METHODS: Twenty-four mini-pigs were divided into 4 groups. The animals were subjected to suprarenal aortic/iliac cross-clamping (for 30 minutes) and by-pass with a Dacron-collagen prosthetic graft impregnated in rifampicin. Groups: 1) sham (aortic dissection alone); 2) cross-clamping and bypass; 3) hemorrhage of 40% of total blood volume before cross-clamping and by-pass; and 4) the same as in group 3 but also including the administration of the NO donor molsidomine (4 mg/kg) 5 minutes before cross-clamping. VARIABLES: 1) bacteriology of mesenteric lymph nodes (MLN), kidney, blood, and prosthesis; 2) serum TNF-alpha (ELISA); and 3) iNOS expression in kidney and liver (Western blot). RESULTS: Aortic cross-clamping with or without hemorrhage was associated with BT in 80% and 100% of the animals, respectively. About 86% of the bacteria isolated in the graft were also present in MLN. This contamination coincided with an increase in TNF-alpha and with a greater expression of iNOS. Molsidomine administration decreased TNF-alpha and iNOS, decreased BT (from 100% to 20% of the animals), and decreased graft contamination (from 83% to 20%). CONCLUSIONS: The present model induces high levels of BT and SIRS, both acted as sources of contamination for the implanted Dacron graft. Molsidomine administration decreased the presence of bacteria in the graft by controlling BT and modulating SIRS.

Postoperative evolution of inflammatory response in a model of suprarenal aortic cross-clamping with and without hemorrhagic shock. Systemic and local reactions.

Surgery of the abdominal aorta generates a systemic inflammatory response (SIR), a source of operative morbidity-mortality. In the present work we attempted to evaluate the evolution of SIR in an experimental model that simulates elective and urgent surgery on the abdominal aorta. Fifteen mini-pigs divided into three groups were used. The animals were subjected to suprarenal aortic/iliac clamping and bypass with a Dacron-collagen prosthetic graft. Groups were as follows: (1) sham (only aortic dissection); (2) clamping and bypass; (3) hemorrhage of 40%, pre-clamping, and bypass. Determinations included (1) tumor necrosis factor-alpha (TNF-alpha) interleukin (IL)-1beta, IL-6, IL-10, interferon-gamma; (2) myeloperoxidase (MPO), superoxide anion (SOA), superoxide dismutase (SOD), and malondialdehyde (MDA); (3) nitrites; (4) iNOS, (5) cell adhesion molecules (ICAM-1, VCAM-1) at 24 hours, 48 hours, and on day 7; and (6) NFkappaB at 48 hours. Our results point to an increase in all inflammatory variables, corroborated by their molecular regulators such as the expression of CAMs, iNOS, and NFkappaB. The alterations tended to normalize by day 7, after reperfusion. The results point to the great importance of SIR at all levels (molecular, nuclear, cellular, and systemic) in situations such as elective and urgent abdominal aorta surgery and the role that control of this response could represent for the future of vascular surgery.

P- and E-selectin blockade can control bacterial translocation and modulate systemic inflammatory response.

Bacterial translocation is an important phenomenon in clinical medicine and leads to an increase in patient morbidity and mortality by multiple organ failure. The selectin family plays an important role in the pathogenesis of inflammation, causing an increase in leukocyte-endothelium interactions and inducing a greater leukocyte's migration. This study considered the effect of a sulfo derivative of Sialyl-Lewis(X), GM 1998-016, that will block the P- and E-selectins interaction with a ligand, the Sialyl-Lewis(X), valuing the modulation of the systemic inflammatory response and the induced translocation. Seventy-five Wistar male rats were injected intraperitoneally with Zymosan A and treated with different doses of GM 1998-016 according to study groups. Measurements of values of qualitative and quantitative microbiology, neutrophil infiltration (myeloperoxidase), oxygen free radicals (superoxide anion, superoxide dismutase, catalase, and gluthatione peroxidase), and cytokines (tumor necrosis factor-alpha and interleukin-1beta) were taken at different times after Zymosan administration. A significant decrease of bacterial translocation, both local (MLN) and systemic (p < .05), was observed, with a decrease in the neutrophil infiltration (p < .001), the oxygen free radicals production (p < .01) and the studied cytokines (p < .01). In conclusion, GM 1998-016 showed a protective effect in an in vivo experimental model of bacterial translocation, downregulating the inflammatory response and the leukocyte-endothelium interactions.

Exogenous nitric oxide modulates the systemic inflammatory response and improves kidney function after risk-situation abdominal aortic surgery.

OBJECTIVE: Renal impairment is a very frequent complication of aortic surgery requiring prolonged suprarenal clamping, especially if it is associated with previous hemorrhage. The aim of this study was to assess the beneficial effect of the administration of a nitric oxide (NO) donor on renal function through a modulation of the systemic inflammatory response in a model of abdominal aortic surgery. METHODS: Twenty-five minipigs were divided into five groups. Under anesthesia, the animals were subjected to suprarenal aortic-iliac clamping (for 30 minutes) and bypass with a Dacron-collagen prosthetic graft impregnated in rifampicin, with or without associated hemorrhage (40% of total blood volume). Prophylaxis with cefazolin was implemented. The five groups were (1) the sham group (only aortic dissection), (2) the clamping and bypass (C) group, (3) hemorrhage preclamping and bypass (H+C) group, (4) the same as group C but with the administration of the NO donor molsidomine (4 mg/kg intravenously) (C+NO group), (5) the same as the H+C group but with the administration of the NO donor molsidomine (4 mg/kg intravenously) (H+C+NO group). The following were determined: (1) kidney function (serum creatinine), (2) serum cytokines (tumor necrosis factor alpha [TNF-alpha] and interleukin-10 [IL-10]); (3) neutrophil infiltration (myeloperoxidase [MPO]) in the kidney, (4) oxygen free radicals (superoxide anion [SOA] and superoxide dismutase [SOD]) in the kidney, (5) serum nitrites, (6) soluble and kidney tissue cell adhesion molecule (soluble intercellular adhesion molecule-1 [sICAM-1], soluble vascular cell adhesion molecule-1 [sVCAM-1], intercellular adhesion molecule-1 [ICAM-1], and vascular cell adhesion molecule-1 [VCAM-1]), (7) inducible nitric oxide synthase (iNOS) in the kidney, and (8) nuclear factor-kappaB (NF-kappaB) in the kidney. Determinations were made during ischemia at 15 minutes post-reperfusion; at 24, 48, and 72 hours; and on day 7. RESULTS: The different insults used in the experimental model led to deterioration in kidney function and an increase in the systemic (and renal) inflammatory response at all levels investigated. Treatment with an NO donor, both with and without associated hemorrhage, reduced the inflammatory response at the systemic (TNF-alpha and IL-10) and kidney (MPO, SOA, and SOD) levels, normalizing kidney function. Likewise, exogenous administration of NO improved the excessive production of NO (nitrites) via iNOS. This was also reflected in a reduction in CAMs and of NF-kappaB expression. The hypotension induced by molsidomine was transitory and did not elicit hemodynamic repercussions. CONCLUSION: In our experimental model, prophylactic treatment with the NO donor molsidomine regulates the systemic inflammatory response and minimizes damage at the kidney level. Clinical Relevance The importance of this article resides in the fact that an experimental study that clarifies the effect of the donors of NO under circumstances as similar as possible to those of the human clinic, such as aortic surgery under hypovolemic shock (ruptured aortic aneurysm) have been little studied, most of these studies being performed in rodents without bypass. Using a model with one or two simultaneous insults (aortic clamping with/without previous hemorrhage) that is very similar to the human clinical situation (abdominal aortic rupture), we confirm the findings of previous work related to the beneficial effects of NO donors.

Exogenous nitric oxide can control SIRS and downregulate NFkappaB.

BACKGROUND: Nitric oxide (NO) participates in inflammation and affects almost all steps of its development. Several experimental studies have unveiled the beneficial effects of NO through modulation of the Systemic Inflammatory Response Syndrome (SIRS). In this sense, in the present work we attempted to evaluate the beneficial effects of exogenous NO and its levels of action (biochemical and cellular) in a model of SIRS induced by two sequential insults. MATERIALS AND METHODS: Dacron graft implantation (first insult) and subsequent administration of Zymosan A (second insult) in Wistar rats. The animals were divided into four groups: 1) No manipulation (Basal); 2) Laparotomy (L) + mineral oil (Sham); 3) L + Graft-Zymosan (GZ) (Control); and 4) L + GZ + NO (Assay). Determinations: Survival, TNF-alpha, SOA, ICAM-1, and NFkappaB. RESULTS: The model established (Control) induced a mortality rate of 20%. Also, it significantly increased the levels of TNF-alpha (P <0.001) and SOA (P <0.01), ICAM-1 expression, and NFkappaB levels (P <0.05). Treatment with NO reduced mortality to 0%, significantly decreasing TNF-alpha (P <0.001) and SOA (P <0.01) levels, ICAM-1 expression, and NFkappaB levels (P <0.05). CONCLUSION: The exogenous administration of NO before the two sequential insults controlled SIRS at biochemical level (TNF-alpha, SOA) and at cellular level (transcription) in a lasting manner. The cascade-like interrelationship of both levels and the study design do not allow us the pinpoint the key to its modulation.