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Copper is ubiquitous as a structural material, and as a reagent in (bio)chemical transformations. A vast number of chemical reactions rely on the near-inevitable preference of copper for positive oxidation states to make useful compounds. Here we show this electronic paradigm can be subverted in a stable compound with a copper-magnesium bond, which conforms to the formal oxidation state of Cu(-I). The Cu-Mg bond is synthesized by the reaction of an N-heterocyclic carbene (NHC) ligated copper alkoxide with a dimeric magnesium(I) compound. Its identity is confirmed by single-crystal X-ray structural analysis and NMR spectroscopy, and computational investigations provide data consistent with a high charge density at copper. The Cu-Mg bond acts as a source of the cupride anion, transferring the NHC-copper fragment to electrophilic s-, p-, and d-block atoms to make known and new copper-containing compounds. Many chemical reactions rely on the preference of copper for positive oxidation states. In this work, the authors report that the reaction of an N-heterocyclic carbene ligated copper alkoxide with a dimeric magnesium(I) compound results in a stable compound with a Cu-Mg bond which acts as a nucleophilic source copper in the formal oxidation state of Cu(-I).

Heightened levels of inflammatory markers are linked to increased morbidity/mortality in people with HIV (PWH) and often remain elevated after virologic suppression by antiretroviral therapy (ART). As new combinations of ART become available, an evaluation of their effects on immune activation and inflammation is warranted. Additionally, it remains unknown whether transient increases in viral load (\"blips\") during ART are associated with increases in inflammation. We utilized cryopreserved samples from treatment-naïve PWH enrolled in two Phase 3 clinical trials investigating the efficacy and safety of bictegravir, emtricitabine and tenofovir alafenamide (B/F/TAF) or dolutegravir, abacavir, and lamivudine (DTG/ABC/3TC) or DTG + F/TAF over a 5-year window (GS-US-380-1489/1490). At week 144, participants were offered the option to switch to open label B/F/TAF for an additional 96 weeks. We measured levels of interleukin-6 (IL-6), C-reactive protein (hsCRP), D-dimer, soluble CD14 (sCD14), and tumor necrosis factor-α receptor 1 (TNFR1) from available baseline, week 24, 48, 144, and 240 samples (B/F/TAF, N=123; DTG/ABC/3TC, N=62; DTG+F/TAF, N=58). Additional samples from PWH who experienced a viral blip (n=44, defined as a single HIV-1 RNA >50c/mL) were also analyzed and paired with the most recent available suppressed sample before the blip. Longitudinal biomarker changes were assessed using a constrained mixed effects linear regression model adjusting for covariates. Baseline demographics and selected laboratory characteristics were similar across groups. Levels of D-dimer, sCD14, and TNFR1 decreased significantly from baseline in all treatment arms, with no significant differences between arms at any timepoint. Biomarker levels also remained stable following ART-switch at week 144. No significant changes in hsCRP or IL-6 were observed versus baseline in any arm at any timepoint. A significant association was observed between sCD14 and increasing viral load (p=0.022) in viral blips; D-dimer also increased with blips in the B/F/TAF arm. Viral suppression was associated with reductions in most inflammatory markers in PWH, with no significant differences among the three ART regimens during the 144-week randomized period. These decreases were sustained after the open label switch to B/F/TAF. Viral blips were associated with increases in monocyte activation (sCD14). Further analysis is needed to confirm these findings and determine the potential impact on clinical outcomes.

BackgroundThe impact of nucleos(t)ide analogues on intrahepatic viral burden and immune microenvironment in patients with chronic hepatitis B (CHB) is not clear.ObjectiveWe aimed to characterise the effects of tenofovir disoproxil fumarate (TDF) on intrahepatic viral burden and the liver immune microenvironment in patients with CHB.DesignCore liver biopsies were collected at baseline and year 3 from patients with CHB with minimally raised serum alanine aminotransferase in a double-blind placebo-controlled trial (NCT01522625). Paired biopsies were analysed by RNA-sequencing (n=119 pairs), a custom multiplex immunofluorescence assay (n=30 pairs), and HBV-targeted long-read DNA sequencing (n=49 pairs).ResultsBoth non-integrated and integrated HBV DNA were present in all patients at baseline, with >65% having interchromosomal translocations. Treatment significantly reduced the frequency of HBV core+ hepatocytes and intrahepatic (integrated and non-integrated) HBV DNA, but had no effect on HBsAg+ hepatocytes. Clonally expanded integrations were enriched for HBsAg coding regions and showed dysregulation of nearby genes. At baseline, there was significant enrichment of intrahepatic CD8+ T cell proximity to HBV core+ hepatocytes, but not to HBsAg+ cells. The densities of T cells and B cells were significantly reduced by TDF. Transcriptomic analyses found TDF induced widespread downregulation of immune-related genes including inhibitory and regulatory genes.ConclusionTDF significantly reduced intrahepatic integrated and non-integrated HBV DNA, exerting disparate effects on HBV core+ and HBsAg+ cells and on different immune cell subsets. Our data suggest there may be differential cytotoxic T cell-mediated killing of HBV core+ versus HBsAg+ hepatocytes, providing insights for HBV cure strategies.

Nodulation in legumes requires the recognition of rhizobially made Nod factors. Genetic studies have revealed that the perception of Nod factors involves LysM domain receptor-like kinases, while biochemical approaches have identified LECTIN NUCLEOTIDE PHOSPHOHYDROLASE (LNP) as a Nod factor-binding protein. Here, we show that antisense inhibition of LNP blocks nodulation in Lotus japonicus. This absence of nodulation was due to a defect in Nod factor signaling based on the observations that the early nodulation gene NODULE INCEPTION was not induced and that both Nod factor-induced perinuclear calcium spiking and calcium influx at the root hair tip were blocked. However, Nod factor did induce root hair deformation in the LNP antisense lines. LNP is also required for infection by the mycorrhizal fungus Glomus intraradices, suggesting that LNP plays a role in the common signaling pathway shared by the rhizobial and mycorrhizal symbioses. Taken together, these observations indicate that LNP acts at a novel position in the early stages of symbiosis signaling. We propose that LNP functions at the earliest stage of the common nodulation and mycorrhization symbiosis signaling pathway downstream of the Nod factor receptors; it may act either by influencing signaling via changes in external nucleotides or in conjunction with the LysM receptor-like kinases for recognition of Nod factor.

Abstract Background TB is an infection caused by Mycobacterium tuberculosis. MDR TB is caused by strains of M. tuberculosis resistant to isoniazid and rifampicin.1 XDR TB refers to strains resistant to one or more second-line injectable drugs and any fluoroquinolone, whereas pre-XDR TB refers to strains resistant to either a second-line injectable drug or a fluoroquinolone.1 The implications of MDR TB include prolonged treatment requirements, increased morbidity and mortality, and risk of onward transmission to others.2 Case history A woman in her forties with poorly controlled diabetes was admitted to hospital three times in 3 months with respiratory symptoms and pulmonary consolidation. She was treated for recurrent community acquired pneumonia (CAP). On her fourth admission, sputum and stool microscopy detected acid fast bacilli (AFB) and PCR using Xpert MTB/RIF (Cepheid® GeneXpert® systems) confirmed M. tuberculosis with resistance to rifampicin. She had no known TB contacts but had had a 5 week holiday in Goa, India, 2 years prior. Management Phenotypic testing confirmed the M. tuberculosis isolate was resistant to rifampicin, isoniazid and aminoglycosides but susceptible to fluoroquinolones. Following discussion with the British Thoracic Society (BTS) MDR TB advice service she was empirically initiated on linezolid 600 mg BD, bedaquiline 200 mg OD, levofloxacin 1000 mg OD, clofazimine 200 mg OD, cycloserine 250 mg BD, pyrazinamide 2000mg OD, ethambutol 1000 mg OD and pyridoxine 10 mg OD. The isolate was later identified as of New Delhi Central Asia lineage, with additional resistance to pyrazinamide (which was then stopped). This is the first case of this lineage reported in the UK. Therapeutic drug monitoring of linezolid, levofloxacin and cycloserine was performed. Cycloserine was changed to terizidone 250 mg BD after 1 month, due to a national supply issue. She suffered from medication side effects including diarrhoea, nausea, derangement in liver functions tests, worsening of pre-existing peripheral neuropathy, myalgia, hypercalcaemia, itch, renal tubular acidosis and acute kidney injury. These were managed pharmacologically and through cessation of terizidone after 2 months and dose reduction, then cessation, of linezolid after 4 months. Outcomes Clinically she improved and repeat imaging showed gradual resolution of consolidation and C-reactive protein levels decreased. She is 10 months into an anticipated 18–24 month treatment regimen, recommended due to her extensive pulmonary disease. Medication side effects are currently well controlled. The infection prevention and control team screened all contacts from this and prior admissions, with no further cases identified. Conclusions This case highlights the importance of suspicion of TB in patients with chronic cough and radiological changes, particularly with risk factors for TB such as relevant travel history and diabetes. MDR TB infection has significant consequences and treatment remains challenging with the burden of multiple drugs, and their side effects, leading to further patient morbidity.

Determining the most likely source of an invasive pest species might help to improve their management by establishing efficient quarantine measures and heading the search of efficient biological control agents. Planococcus ficus is an invasive mealybug pest of vineyards in Argentina, California, Mexico, Peru and South Africa. This mealybug pest had a previously known geographic distribution spanning southern Europe, the Middle East, and parts of northern Africa. In North America, Pl. ficus was first discovered in the early 1990s and soon thereafter in Mexico. To determine the origin of invasive populations in North America, Pl. ficus from California and Mexico were compared with material throughout its presumptive native range in the Mediterranean region, as well as material collected from an older invasion in South Africa and recently invaded Argentina. From each sample location, genomic DNA was sequenced for the nuclear internal transcribed spacer one (ITS1) and the mitochondrial cytochrome c. oxidase one (CO1). Phylogenetic analyses of CO1, ITS1 and concatenated CO1 and ITS1 data-sets using Bayesian and neighbor-joining analysis support two major divisions: a European grouping (Europe, Tunisia, Turkey) and a Middle Eastern grouping (Israel and Egypt). The invasive populations in Argentina and South Africa align with the European group and the invasive populations in North America align with the Middle Eastern group, with one Israel sample aligning closely with the North American Glade, suggesting that Israel was the origin of those populations.

PurposeVenous thromboembolism (VTE) in injured children is rare, but sequelae can be morbid and life-threatening. Recent trauma society guidelines suggesting that all children over 15 years old should receive thromboprophylaxis may result in overtreatment. We sought to evaluate the efficacy of a previously published VTE prediction algorithm and compare it to current recommendations.MethodsTwo institutional trauma registries were queried for all pediatric (age < 18 years) patients admitted from 2007 to 2018. Clinical data were applied to the algorithm and the area under the receiver operating characteristic (AUROC) curve was calculated to test algorithm efficacy.ResultsA retrospective review identified 8271 patients with 30 episodes of VTE (0.36%). The VTE prediction algorithm classified 51 (0.6%) as high risk (> 5% risk), 322 (3.9%) as moderate risk (1–5% risk) and 7898 (95.5%) as low risk (< 1% risk). AUROC was 0.93 (95% CI 0.89–0.97). In our population, prophylaxis of the ‘moderate-’ and ‘high-risk’ cohorts would outperform the sensitivity (60% vs. 53%) and specificity (96% vs. 77%) of current guidelines while anticoagulating substantially fewer patients (373 vs. 1935, p < 0.001).ConclusionA VTE prediction algorithm using clinical variables can identify injured children at risk for venous thromboembolic disease with more discrimination than current guidelines. Prospective studies are needed to investigate the validity of this model.Level of evidenceIII—Clinical decision rule evaluated in a single population.

Objective To review the evidence on diagnostic accuracy of red flag signs and symptoms to screen for fracture or malignancy in patients presenting with low back pain to primary, secondary, or tertiary care.Design Systematic review.Data sources Medline, OldMedline, Embase, and CINAHL from earliest available up to 1 October 2013.Inclusion criteria Primary diagnostic studies comparing red flags for fracture or malignancy to an acceptable reference standard, published in any language.Review methods Assessment of study quality and extraction of data was conducted by three independent assessors. Diagnostic accuracy statistics and post-test probabilities were generated for each red flag.Results We included 14 studies (eight from primary care, two from secondary care, four from tertiary care) evaluating 53 red flags; only five studies evaluated combinations of red flags. Pooling of data was not possible because of index test heterogeneity. Many red flags in current guidelines provide virtually no change in probability of fracture or malignancy or have untested diagnostic accuracy. The red flags with the highest post-test probability for detection of fracture were older age (9%, 95% confidence interval 3% to 25%), prolonged use of corticosteroid drugs (33%, 10% to 67%), severe trauma (11%, 8% to 16%), and presence of a contusion or abrasion (62%, 49% to 74%). Probability of spinal fracture was higher when multiple red flags were present (90%, 34% to 99%). The red flag with the highest post-test probability for detection of spinal malignancy was history of malignancy (33%, 22% to 46%).Conclusions While several red flags are endorsed in guidelines to screen for fracture or malignancy, only a small subset of these have evidence that they are indeed informative. These findings suggest a need for revision of many current guidelines.

Background Numerous clinical tests are used in the diagnosis of anterior cruciate ligament (ACL) injury but their accuracy is unclear. The purpose of this study is to evaluate the diagnostic accuracy of clinical tests for the diagnosis of ACL injury. Methods Study Design: Systematic review. The review protocol was registered through PROSPERO (CRD42012002069). Electronic databases (PubMed, MEDLINE, EMBASE, CINAHL) were searched up to 19th of June 2013 to identify diagnostic studies comparing the accuracy of clinical tests for ACL injury to an acceptable reference standard (arthroscopy, arthrotomy, or MRI). Risk of bias was appraised using the QUADAS-2 checklist. Index test accuracy was evaluated using a descriptive analysis of paired likelihood ratios and displayed as forest plots. Results A total of 285 full-text articles were assessed for eligibility, from which 14 studies were included in this review. Included studies were deemed to be clinically and statistically heterogeneous, so a meta-analysis was not performed. Nine clinical tests from the history (popping sound at time of injury, giving way, effusion, pain, ability to continue activity) and four from physical examination (anterior draw test, Lachman’s test, prone Lachman’s test and pivot shift test) were investigated for diagnostic accuracy. Inspection of positive and negative likelihood ratios indicated that none of the individual tests provide useful diagnostic information in a clinical setting. Most studies were at risk of bias and reported imprecise estimates of diagnostic accuracy. Conclusion Despite being widely used and accepted in clinical practice, the results of individual history items or physical tests do not meaningfully change the probability of ACL injury. In contrast combinations of tests have higher diagnostic accuracy; however the most accurate combination of clinical tests remains an area for future research. Clinical relevance Clinicians should be aware of the limitations associated with the use of clinical tests for diagnosis of ACL injury.