Recurrent mobile bearing dislocation after minimally invasive unicompartmental knee arthroplasty

Over the last three decades, unicompartmental knee arthroplasty (UKA) has varied in its popularity. More recently the minimally invasive technique with improved instrumentation has resulted in a strong resurgence of interest in unicompartmental arthroplasty. Either in long term or short ones, UKA has shown excellent results specially if the surgeon follows the very delicate criteria for case selection. Even though it is a very demanding technique, the indications for UKA have expanded and only time will allow us to evaluate these changes. There is a significant learning curve in performing UKA through the minimally invasive technique. We report a case of recurrent dislocation of a mobile bearing polyethylene insert which required conversion to a total knee arthroplasty.Transcurridas las últimas tres décadas, la artroplastia unicameral de rodilla (AUR) ha variado en popularidad y aceptación. Recientemente, la técnica miniinvasiva con el avance de la nueva instrumentación, han logrado una fuerte reaparición en el interés de la artroplastia unicompartimental. Ya en largas o breves series, la AUR presenta excelentes resultados en especial si, el cirujano sigue escrupulosamente los criterios de selección de casos. Las indicaciones para la AUR han sido ampliadas y, únicamente el tiempo nos facilitará el poder evaluar estas variaciones. Hay una notoria curva de aprendizaje en la ejecución de la AUR a través de la técnica miniinvasiva. Presentamos un caso de luxación recurrente de un platillo meniscal de polietileno móvil implantado, que precisó un recambio a una prótesis total de rodilla

Biomarkers differentiate drug-induced liver injury from other liver injury: PONDER study

Background and Aim: Drug-induced liver injury (DILI) is a known complication of volatile anesthetic (VA) agents, and, despite being rare, DILI can be serious. One mechanism of VA-DILI occurs via interleukin 4 (IL-4)driven upregulation of cytochrome P450-2E1, leading to the formation of drug metabolites (haptens) that trigger IL-4-driven antigen-specific T cells and autoantibodies. Our group has developed biomarkers for liver injury and have examined this in patients before and after VA exposure. The aim of this prospective study was to determine the early markers of VA-DILI. Methods: We prospectively followed patients having a VA general anesthetic (sevoflurane and/or desflurane) and compared them with those who received regional or total intravenous anesthesia. Exclusion criteria were known liver disease or any episode of significant hypotension. Baseline data on patient demographics and comorbidities were collected, and blood was analyzed for liver biochemistry, macrophage activation markers (CD206, CD163), and IgG1 and IgG4 antibodies to JHDN5 (the CYP2E1 epitope) and trifluoroacetyl (TFA), the VA drug hapten. Follow-up blood samples were taken 48 h postoperatively and compared with baseline results. DILI was defined as an alanine aminotransferase (ALT) level greater than two times the upper limit of normal (ULN) and post-review agreement by an expert panel, taking into account the pattern of liver function test result derangement and intraoperative events. Results: Of 229 patients recruited, 16 developed an ALT level > 2 × ULN. Twelve were considered likely to have VA-DILI, including four with an ALT rise >3 × ULN. There was a trend to associate VA-DILI with obesity (RR, 2.98; P = 0.063); however, the association with dyslipidemia (RR, 1.47; P = 0.72), male sex (RR, 1.18; P = 0.76), history of atopy (RR, 1.16; P = 0.79), and heavy ethanol consumption (RR, 1.09; P = 0.89) was not statistically significant. Prior VA exposure was not a risk factor (RR, 0.89; P = 0.83). There was a rise in CD206 and decline in CD163 from baseline in all patients. However, in the patients with VA-DILI, the levels were significantly different from all other groups. TFA IgG1 and IgG4 antibodies were elevated in the VA-DILI group when compared with controls. Conclusion: Recognizing that our results may be skewed by our cohort, this work suggests the known immunological pathway mediated by IL-4 in response to an injury: rise in CD206 to stimulate an inflammatory response, and decrease in CD163 to modulate the response. The increase in TFA IgG1 and IgG4 antibodies in the VA-DILI group is consistent with metabolism and the heightened immune response in those who develop DILI. At this early juncture, JHDN5 IgG4 autoantibodies were not detected. Ongoing work is looking at other DILI, and how these markers can be used in DILI

Predicting photooxidant concentrations in aerosol liquid water based on laboratory extracts of ambient particles

Aerosol liquid water (ALW) is a unique reaction medium, but its chemistry is poorly understood. For example, little is known of photooxidant concentrations – including hydroxyl radicals (⚫OH), singlet molecular oxygen (1O2*), and oxidizing triplet excited states of organic matter (3C*) – even though they likely drive much of ALW chemistry. Due to the very limited water content of particles, it is difficult to quantify oxidant concentrations in ALW directly. To predict these values, we measured photooxidant concentrations in illuminated aqueous particle extracts as a function of dilution and used the resulting oxidant kinetics to extrapolate to ALW conditions. We prepared dilution series from two sets of particles collected in Davis, California: one from winter (WIN) and one from summer (SUM). Both periods are influenced by biomass burning, with dissolved organic carbon (DOC) in the extracts ranging from 10 to 495 mg C  L−1. In the winter sample, the ⚫OH concentration is independent of particle mass concentration, with an average value of 5.0 (± 2.2) × 10−15 M, while in summer ⚫OH increases with DOC in the range (0.4–7.7) × 10−15 M. In both winter and summer samples, 3C* concentrations increase rapidly with particle mass concentrations in the extracts and then plateau under more concentrated conditions, with a range of (0.2–7) × 10−13 M. WIN and SUM have the same range of 1O2* concentrations, (0.2–8.5) × 10−12 M, but in WIN the 1O2* concentration increases linearly with DOC, while in SUM 1O2* approaches a plateau. We next extrapolated the relationships of oxidant formation rates and sinks as a function of particle mass concentration from our dilute extracts to the much more concentrated condition of aerosol liquid water. Predicted ⚫OH concentrations in ALW (including mass transport of ⚫OH from the gas phase) are (5–8) × 10−15 M, similar to those in fog/cloud waters. In contrast, predicted concentrations of 3C* and 1O2* in ALW are approximately 10 to 100 times higher than in cloud/fogs, with values of (4–9) × 10−13 M and (1–5) × 10−12 M, respectively. Although ⚫OH is often considered the main sink for organic compounds in the atmospheric aqueous phase, the much higher concentrations of 3C* and 1O2* in aerosol liquid water suggest these photooxidants will be more important sinks for many organics in particle water.</p

Seasonal variations in photooxidant formation and light absorption in aqueous extracts of ambient particles

Fog/cloud drops and aerosol liquid water are important sites for the transformations of atmospheric species, largely through reactions with photoformed oxidants such as the hydroxyl radical (⚫OH), singlet molecular oxygen (1O2∗), and oxidizing triplet excited states of organic matter (3C∗). Despite their importance, few studies have measured these oxidants or their seasonal variations. To address this gap, we collected ambient PM2.5 from Davis, California, over the course of a year and measured photooxidant concentrations and light absorption in dilute aqueous extracts. Mass absorption coefficients (MACs) normalized by dissolved organic carbon range from 0.4–3.8 m2 per gram C at 300 nm. Concentrations of ⚫OH, 1O2∗, and 3C∗ in the extracts range from (0.2–4.7) × 10−15 M, (0.7–45) × 10−13 M, and (0.03–7.9) × 10−13 M, respectively, with biomass burning brown carbon playing a major role in light absorption and the formation of 1O2∗ and 3C∗. Extrapolating photooxidant kinetics from our dilute particle extracts to concentrated aerosol liquid water (ALW) conditions gives an estimated ⚫OH concentration of 7 × 10−15 M and ranges for 1O2∗ and 3C∗ of (0.6–7) × 10−12 M and (0.2–1) × 10−12 M, respectively. Compared to the results in Kaur et al. (2019), our ALW predictions show roughly 10 times higher ⚫OH, up to 5 times higher 3C, and 1O2∗ concentrations that are lower by factors of 20–100. These concentrations suggest that 3C∗ and 1O2∗ in ALW dominate the processing of organic compounds that react quickly with these oxidants (e.g., phenols and furans, respectively), while ⚫OH is more important for less reactive organics.</p

Mineralization, alteration assemblages and stable isotopes of the intermediate-sulfidation epithermal Strauss Deposit, Drake Goldfield, North-Eastern NSW, Australia

The intermediate-sulfidation epithermal Strauss deposit is part of the Drake Goldfield of north-eastern NSW, Australia. The mineralization is gold dominant with minor silver and significant zinc, copper and lead. Strauss has a combined total resource of 2.66 Mt @ 1.5 g/T Au and 1.9 g/T Ag. Petrographic analysis has shown the deposit to be hosted by varying layers of dacitic ash flow tuffs and a cross-cutting lamprophyre dyke though previous authors classified some of the tuffs as intrusive andesites. Mineralization mainly occurs in the form of vein stockworks of three main orientations. Structural analysis indicates that these resulted from two fault system events and one conjugate fault system. Petrographic and SEM analysis shows that there are two different mineralization styles, a pyrite dominant and chalcopyrite dominant assemblage, with three main mineralization events. Correlation analysis for the assay data indicates that Au has a strong relationship with Ag and a moderate correlation with Pb. XRD analysis indicates widespread argillic-phyllic and propylitic alteration. Silver tellurides have been found as late-stage grains associated with the chalcopyrite mineralization assemblage. Sr shows a significant depletion due to the intense and pervasive alteration at Strauss. The carbon and oxygen isotopes of the vein carbonates suggests that the carbon from the late-stage carbonates was derived from a magmatic source with a significant input of low temperature meteoric water, while the sulfur isotopes indicate a magmatic sulfur source

Full sphere hydrodynamic and dynamo benchmarks

Convection in planetary cores can generate fluid flow and magnetic fields, and a number of sophisticated codes exist to simulate the dynamic behaviour of such systems. We report on the first community activity to compare numerical results of computer codes designed to calculate fluid flow within a whole sphere. The flows are incompressible and rapidly rotating and the forcing of the flow is either due to thermal convection or due to moving boundaries. All problems defined have solutions that allow easy comparison, since they are either steady, slowly drifting or perfectly periodic. The first two benchmarks are defined based on uniform internal heating within the sphere under the Boussinesq approximation with boundary conditions that are uniform in temperature and stress-free for the flow. Benchmark 1 is purely hydrodynamic, and has a drifting solution. Benchmark 2 is a magnetohydrodynamic benchmark that can generate oscillatory, purely periodic, flows and magnetic fields. In contrast, Benchmark 3 is a hydrodynamic rotating bubble benchmark using no slip boundary conditions that has a stationary solution. Results from a variety of types of code are reported, including codes that are fully spectral (based on spherical harmonic expansions in angular coordinates and polynomial expansions in radius), mixed spectral and finite difference, finite volume, finite element and also a mixed Fourier–finite element code. There is good agreement between codes. It is found that in Benchmarks 1 and 2, the approximation of a whole sphere problem by a domain that is a spherical shell (a sphere possessing an inner core) does not represent an adequate approximation to the system, since the results differ from whole sphere results

Mineralization, alteration assemblages, geochemistry and stable isotopes of the intermediate-sulfidation epithermal Kylo Deposit, Drake Goldfield, North-Eastern NSW, Australia: evidence for a significant magmatic fluid component

The intermediate-sulfidation epithermal Kylo deposit is part of the Drake Goldfield of north-eastern NSW. The mineralization is gold-dominant with minor silver and significant levels of zinc, copper and lead. Kylo has a resource of 2.298 Mt @ 1.23 g/T Au and 1.35 g/T Ag. Mineralization mainly occurs in the form of vein stockworks. Petrographic and SEM analysis shows that there are at least three mineralization events, with Au mineralization strongly associated with at least a deposit-scale alteration event. Quantitative XRD analysis shows a positive correlation between Au-mineralization and argillic-phyllic alteration. Electrum was found as an inclusion in massive sphalerite in the main mineralization stage. Correlation analysis for the assay data indicates that Au has a strong relation with Ag and Pb. Petrographic and geochemical analysis has identified three lithologies: rhyolite, rhyodacite/dacite and andesite, with Au mineralization more associated with the rhyodacites, while at deeper levels some of the andesites also show a relatively strong correlation with Au. Strontium shows a significant strong depletion, due to the intense and pervasive alteration at Kylo. The andesitic volcanics show moderate LREE enrichment with small negative Eu anomalies, and relative depletion in Nb, Ta and Ti, indicating an island arc tectonic setting. The carbon and oxygen isotopes of late-stage vein carbonates suggest that the late-stage fluid was mostly derived from a magmatic source, but with a minor contribution from low-temperature fluids intimately associated with alteration processes. The sulfur isotopes indicate that the sulfide mineralization had a magmatic sulfur source

Copy Number Variation Affecting the Photoperiod-B1 and Vernalization-A1 Genes Is Associated with Altered Flowering Time in Wheat (Triticum aestivum)

The timing of flowering during the year is an important adaptive character affecting reproductive success in plants and is critical to crop yield. Flowering time has been extensively manipulated in crops such as wheat (Triticum aestivum L.) during domestication, and this enables them to grow productively in a wide range of environments. Several major genes controlling flowering time have been identified in wheat with mutant alleles having sequence changes such as insertions, deletions or point mutations. We investigated genetic variants in commercial varieties of wheat that regulate flowering by altering photoperiod response (Ppd-B1 alleles) or vernalization requirement (Vrn-A1 alleles) and for which no candidate mutation was found within the gene sequence. Genetic and genomic approaches showed that in both cases alleles conferring altered flowering time had an increased copy number of the gene and altered gene expression. Alleles with an increased copy number of Ppd-B1 confer an early flowering day neutral phenotype and have arisen independently at least twice. Plants with an increased copy number of Vrn-A1 have an increased requirement for vernalization so that longer periods of cold are required to potentiate flowering. The results suggest that copy number variation (CNV) plays a significant role in wheat adaptation