Summary
Collections of micro‐organisms are a crucial element of life science research infrastructure but are vulnerable to loss and damage caused by natural or man‐made disasters, the untimely death ...or retirement of personnel, or the loss of research funding. Preservation of biological collections has risen in priority due to a new appreciation for discoveries linked to preserved specimens, emerging hurdles to international collecting and decreased funding for new collecting. While many historic collections have been lost, several have been preserved, some with dramatic rescue stories. Rescued microbes have been used for discoveries in areas of health, biotechnology and basic life science. Suggestions for long‐term planning for microbial stocks are listed, as well as inducements for long‐term preservation.
Cellulose synthase and other members of the family 2 glycosyltransferases are ubiquitous in all kingdoms of life. To date, no attempt has been made to construct a phylogeny that positions cellulose ...synthases in relation to other members of this family or to elucidate relationships within the cellulose synthase group. In this study, a sequence from the unicellular, marine cyanobacterium Synechococcus sp. PCC 7002 is shown to share a unique common ancestor of a clade consisting of cellulose synthases from Dictyostelium discoideum and Nostoc, as well as a plant grouping that includes CesA proteins and cellulose synthase-like (Csl) proteins G, E, B, D, and F. A branching order is established for Csl proteins that places CslG as ancestral to other members of the Csl/CesA clade. Sequences from Ciona intestinalis and Aspergillis fumigatus are shown to branch at the base of the Eukaryota/Cyanobacteria clade. These data suggest multiple independent transfers of cellulose synthases. The implications of these findings in relation to the evolutionary history of cellulose synthase are discussed.
Background: The use of laparoscopic surgical procedures without previous training has grown rapidly. At the same time, there have been allegations of increased complications among less experienced ...surgeons.
Methods: Using multivariate regression analyses, we evaluated the relationship between bile duct injury rate and experience with laparoscopic cholecystectomy for surgeons in the Southern Surgeons Club.
Results: Fifty-five surgeons performed 8,839 procedures. Fifteen bile duct injuries (by 13 surgeons) resulted with 90% of the injuries occurring within the first 30 cases performed by an individual surgeon. Multivariate analyses indicated that the only significant factor associated with an adverse outcome was the surgeon's experience with the procedure. A regression model predicted that a surgeon had a 1.7% chance of a bile duct injury occurring in the first case and a 0.17% chance of a bile duct injury at the 50th case.
Conclusions: While surgeons appear to learn this procedure rapidly, institutions might consider requiring surgeons to move beyond the initial learning curve before awarding privileges.
Summary Background Coronary artery bypass grafting (CABG) is the standard treatment for revascularisation in patients with left main coronary artery disease, but use of percutaneous coronary ...intervention (PCI) for this indication is increasing. We aimed to compare PCI and CABG for treatment of left main coronary artery disease. Methods In this prospective, randomised, open-label, non-inferiority trial, patients with left main coronary artery disease were enrolled in 36 centres in northern Europe and randomised 1:1 to treatment with PCI or CABG. Eligible patients had stable angina pectoris, unstable angina pectoris, or non-ST-elevation myocardial infarction. Exclusion criteria were ST-elevation myocardial infarction within 24 h, being considered too high risk for CABG or PCI, or expected survival of less than 1 year. The primary endpoint was major adverse cardiac or cerebrovascular events (MACCE), a composite of all-cause mortality, non-procedural myocardial infarction, any repeat coronary revascularisation, and stroke. Non-inferiority of PCI to CABG required the lower end of the 95% CI not to exceed a hazard ratio (HR) of 1·35 after up to 5 years of follow-up. The intention-to-treat principle was used in the analysis if not specified otherwise. This trial is registered with ClinicalTrials.gov identifier, number NCT01496651. Findings Between Dec 9, 2008, and Jan 21, 2015, 1201 patients were randomly assigned, 598 to PCI and 603 to CABG, and 592 in each group entered analysis by intention to treat. Kaplan-Meier 5 year estimates of MACCE were 28% for PCI (121 events) and 18% for CABG (80 events), HR 1·51 (95% CI 1·13–2·00), exceeding the limit for non-inferiority, and CABG was significantly better than PCI (p=0·0044). As-treated estimates were 28% versus 18% (1·48, 1·11–1·98, p=0·0069). Comparing PCI with CABG, 5 year estimates were 11% versus 9% (1·08, 0·67–1·74, p=0·84) for all-cause mortality, 6% versus 2% (2·87, 1·40–5·89, p=0·0040) for non-procedural myocardial infarction, 15% versus 10% (1·50, 1·04–2·17, p=0·0304) for any revascularisation, and 5% versus 2% (2·20, 0·91–5·36, p=0·08) for stroke. Interpretation The findings of this study suggest that CABG might be better than PCI for treatment of left main stem coronary artery disease. Funding Biosensors, Aarhus University Hospital, and participating sites.
A 3-year-old girl with a history of bilateral retinoblastoma presented with a new right lower periorbital mass that showed calcifications on ultrasound. She had previously undergone systemic and ...intra-arterial chemotherapy for retinoblastoma but had no evidence of active disease for at least 6 months previously. Her family and oncologists feared that this mass was an extraocular metastasis of her retinoblastoma. On excision, it was diagnosed as a pilomatrixoma, an uncommon benign neoplasm that originates from the matrix of the hair root. This is the first reported case of pilomatrixoma in a patient with retinoblastoma.
CRISPR-Cas9 gene editing provides a powerful tool to enhance the natural ability of human T cells to fight cancer. We report a first-in-human phase 1 clinical trial to test the safety and feasibility ...of multiplex CRISPR-Cas9 editing to engineer T cells in three patients with refractory cancer. Two genes encoding the endogenous T cell receptor (TCR) chains, TCRα (
) and TCRβ (
), were deleted in T cells to reduce TCR mispairing and to enhance the expression of a synthetic, cancer-specific TCR transgene (NY-ESO-1). Removal of a third gene encoding programmed cell death protein 1 (PD-1;
), was performed to improve antitumor immunity. Adoptive transfer of engineered T cells into patients resulted in durable engraftment with edits at all three genomic loci. Although chromosomal translocations were detected, the frequency decreased over time. Modified T cells persisted for up to 9 months, suggesting that immunogenicity is minimal under these conditions and demonstrating the feasibility of CRISPR gene editing for cancer immunotherapy.
Clonal expansion of infected CD4+ T cells is a major mechanism of HIV-1 persistence and a barrier to achieving a cure. Potential causes are homeostatic proliferation, effects of HIV-1 integration, ...and interaction with antigens. Here, we show that it is possible to link antigen responsiveness, the full proviral sequence, the integration site, and the T cell receptor β-chain (TCRβ) sequence to examine the role of recurrent antigenic exposure in maintaining the HIV-1 reservoir. We isolated CMV- and Gag-responding CD4+ T cells from 10 treated individuals. Proviral populations in CMV-responding cells were dominated by large clones, including clones harboring replication-competent proviruses. TCRβ repertoires showed high clonality driven by converging adaptive responses. Although some proviruses were in genes linked to HIV-1 persistence (BACH2, STAT5B, MKL1), the proliferation of infected cells under antigenic stimulation occurred regardless of the site of integration. Paired TCRβ and integration site analysis showed that infection could occur early or late in the course of a clone's response to antigen and could generate infected cell populations too large to be explained solely by homeostatic proliferation. Together, these findings implicate antigen-driven clonal selection as a major factor in HIV-1 persistence, a finding that will be a difficult challenge to eradication efforts.
We report a patient relapsing 9 months after CD19-targeted CAR T cell (CTL019) infusion with CD19
leukemia that aberrantly expressed the anti-CD19 CAR. The CAR gene was unintentionally introduced ...into a single leukemic B cell during T cell manufacturing, and its product bound in cis to the CD19 epitope on the surface of leukemic cells, masking it from recognition by and conferring resistance to CTL019.
A stable latent reservoir for HIV-1 in resting CD4
T cells is the principal barrier to a cure
. Curative strategies that target the reservoir are being tested
and require accurate, scalable reservoir ...assays. The reservoir was defined with quantitative viral outgrowth assays for cells that release infectious virus after one round of T cell activation
. However, these quantitative outgrowth assays and newer assays for cells that produce viral RNA after activation
may underestimate the reservoir size because one round of activation does not induce all proviruses
. Many studies rely on simple assays based on polymerase chain reaction to detect proviral DNA regardless of transcriptional status, but the clinical relevance of these assays is unclear, as the vast majority of proviruses are defective
. Here we describe a more accurate method of measuring the HIV-1 reservoir that separately quantifies intact and defective proviruses. We show that the dynamics of cells that carry intact and defective proviruses are different in vitro and in vivo. These findings have implications for targeting the intact proviruses that are a barrier to curing HIV infection.
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