The first enantioselective total synthesis and structural reassignment of (−)-thelepamide, a cytotoxic tetraketide–amino acid from the marine worm Thelepus crispus, is reported. A convergent approach ...provides access to all thelepamide diastereomers in six steps from four simple building blocks. Key features of the synthesis include the application of Melchiorre’s organocatalytic thia-Michael reaction and a sonication-assisted assembly of an unprecedented N,O-acetal–hemiacetal moiety. The corrected structure was confirmed by NMR–DFT analysis.
In this paper we report on the gravitational-wave signal computed in the context of a three-dimensional simulation of a core-collapse supernova explosion of a 15M ⊙ star. The simulation was performed ...with our neutrino hydrodynamics code chimera . We detail the gravitational wave strains as a function of time, for both polarizations, and discuss their physical origins. We also present the corresponding spectral signatures. Gravitational wave emission in our model has two key features: low-frequency emission (less than 200 Hz) emanates from the gain layer as a result of neutrino-driven convection and the standing accretion shock instability (SASI), and high-frequency emission (greater than 600 Hz) emanates from the proto–neutron star due to Ledoux convection within it. The high-frequency emission dominates the gravitational wave emission in our model and emanates largely from the convective layer itself, not from the convectively stable layer above it, due to convective overshoot. Moreover, the low-frequency emission emanates from the gain layer itself, not from the proto–neutron star, due to accretion onto it. We provide evidence of the SASI in our model and demonstrate that the peak of our low-frequency gravitational wave emission spectrum corresponds to it. Given its origin in the gain layer, we classify the SASI emission in our model as p-mode emission and assign a purely acoustic origin, not a vortical–acoustic origin, to it. We compare the results of our three-dimensional model analysis with those obtained from the model’s two-dimensional counterpart and find a significant reduction in the strain amplitudes in the former case, as well as significant reductions in all related quantities. Our dominant proto–neutron star gravitational wave emission is not well characterized by emission from surface g modes, complicating the relationship between peak frequencies observed and the mass and radius of the proto–neutron star expressed by analytic estimates under the assumption of surface g-mode emission. We present our frequency normalized characteristic strain along with the sensitivity curves of current- and next-generation gravitational wave detectors. This simple analysis indicates that the spectrum of gravitational wave emission between approximately 20 Hz and approximately 1 kHz, stemming from neutrino-driven convection, the SASI, accretion onto the proto–neutron star, and proto–neutron star convection, will be accessible for a Galactic event.
The objectives were: (1) to develop a more rapid, reduced serum culture system for Caco-2 monolayers, relative to the traditional 21-day, 10% fetal bovine serum (FBS) system; and (2) to determine the ...biopharmaceutical drug classification of an oral therapeutic agent using this new system. Caco-2 cells were grown in the six well format on polycarbonate filters, in medium containing 2% iron supplemented calf serum (sCS) and a combination of growth factors and hormones. After 4 days in culture, permeabilities of three marker compounds (metoprolol, mannitol, and taurocholate) across monolayers were determined, and compared to permeabilities from the traditional 21-day, 10% FBS system, using cells at similar passage number. Cell morphology, degree of cell differentiation, and the presence of two efflux pumps were assessed. The 2% sCS model was also used to classify the permeability of an oral therapeutic agent as high or low. No difference in permeability was observed for metoprolol transport (
P=0.38) between the two culture methods, and the values obtained were independent of passage number of the cells. Mannitol permeability was about 2-fold higher from the 2% sCS system, as compared to the 10% FBS system. Taurocholate permeability was low indicating the 2% sCS culture at 4 days lacked this particular active transporter capability. Electron micrographs of cells grown in the 2% sCS system at 4 days revealed the presence of microvilli and tight junctions. P-glycoprotein and an efflux pump for furosemide were functionally present. The 2% sCS system indicated the oral therapeutic agent as highly permeable, which agreed with the 10% FBS system. This new system provides a rapid, accurate, and economical option for passive permeability determination, and appears to be applicable to the proposed Biopharmaceutics Classification System (BCS).
Genetics play a significant role in venous thromboembolism (VTE), yet current clinical laboratory-based testing identifies a known heritable thrombophilia (factor V Leiden, prothrombin gene mutation ...G20210A, or a deficiency of protein C, protein S, or antithrombin) in only a minority of VTE patients. We hypothesized that a substantial number of VTE patients could have lesser-known thrombophilia mutations. To test this hypothesis, we performed whole-exome sequencing (WES) in 64 patients with VTE, focusing our analysis on a novel 55-gene extended thrombophilia panel that we compiled. Our extended thrombophilia panel identified a probable disease-causing genetic variant or variant of unknown significance in 39 of 64 study patients (60.9%), compared with 6 of 237 control patients without VTE (2.5%) (P < .0001). Clinical laboratory-based thrombophilia testing identified a heritable thrombophilia in only 14 of 54 study patients (25.9%). The majority of WES variants were either associated with thrombosis based on prior reports in the literature or predicted to affect protein structure based on protein modeling performed as part of this study. Variants were found in major thrombophilia genes, various SERPIN genes, and highly conserved areas of other genes with established or potential roles in coagulation or fibrinolysis. Ten patients (15.6%) had >1 variant. Sanger sequencing performed in family members of 4 study patients with and without VTE showed generally concordant results with thrombotic history. WES and extended thrombophilia testing are promising tools for improving our understanding of VTE pathogenesis and identifying inherited thrombophilias.
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•Using WES, we designed an extended thrombophilia panel consisting of 55 genes of significance to thrombosis.•The extended thrombophilia panel identified multiple novel genetic variants with predicted roles in thrombosis or thrombophilia.
Objective
To determine the long‐term success of the periurethral injection of collagen (Contigen® , Bard UK) in women with genuine stress incontinence.
Patients and methods
Sixty‐one women with ...genuine stress incontinence were enrolled in a trial of periurethral collagen injections between 1 September 1990 and 31 August 1992. They were assessed at 1, 3, 6, 12 and 24 months after the last collagen injection. In 1998, their notes were reviewed, and a standardized questionnaire was sent to 46 women who were still alive and had undergone no further anti‐incontinence surgery.
Results
Of the 53 women who were either known failures or who had follow‐up information beyond 5 years, 26% were subjectively improved. Women who had a maximum urethral closure pressure of >20 cmH2O and those who had urinary incontinence for <10 years before their first injection were more likely to have had long‐term success. There was no correlation between long‐term success and the number of previous operations, body mass index, age or preoperative pad loss. Neither the number of injection sessions, total volume of collagen injected nor perceived bulking at the time of surgery affected long‐term success rates. Of the 14 women who considered themselves subjectively improved, seven had daily incontinence and only one was completely dry. Urinary retention and urinary tract infection were the most common complications. In addition, one woman reported a flare‐up of her skin test and transient ‘flu‐like symptoms 2 weeks after the injection, and one woman developed a right upper lobe pneumonia 2 weeks after the collagen injection.
Conclusion
The long‐term results of periurethral collagen injections are disappointing. We found no evidence to support the use of periurethral collagen injections in women with intrinsic sphincter deficiency, who had a higher failure rate than those with hypermobility. Further research is essential to develop agents that are not immunogenic, produce minimal inflammatory response and yet are durable.
Striking cell losses occur during late B lymphocyte maturation 1–3, reflecting BcR-mediated selection coupled with requisites for viability promoting signals 4–11. How selection and survival cues are ...integrated remains unclear, but a key role for B lymphocyte stimulator (BLySTM; trademark of Human Genome Sciences, Inc.) is suggested by its marked effects on B cell numbers and autoantibody formation 12–18 as well as the B lineage-specific expression of BLyS receptors 19–23. Our analyses of the B cell-deficient A/WySnJ mouse have established Bcmd as a gene controlling follicular B cell life span 24–27, and recent reports show Bcmd encodes a novel BLyS receptor 23, 28, 29. Here we show that A/WySnJ B cells are unresponsive to BLyS, affording interrogation of how Bcmd influences B cell homeostasis. Mixed marrow chimeras indicate A/WySnJ peripheral B cells compete poorly for peripheral survival. Moreover, in vivo BrdU labeling shows that (A/WySnJ × BALB/c)F1 B cells have an intermediate but uniform life span, indicating viability requires continuous signaling via this pathway. Together, these findings establish the BLyS/Bcmd pathway as a dominant mediator of B cell survival, suggesting competition for BLyS/Bcmd signals regulates follicular B cell numbers.
Purpose: People living with osteoarthritis (OA) often do not receive best evidence care. Coordinated OA management programs (OAMPs) have been implemented to address this global evidence-practice gap. ...An OAMP is defined as a package of care with the following: i) a personalized management plan; ii) with reassessment and progression; iii) using a minimum of 2 core treatments (education, exercise, weight control), and; iv) optional adjunctive therapies. Existing OAMP models differ in treatment mode, intensity, duration, the health professionals delivering care, and the healthcare systems and settings they operate within. Randomized trials (RCTs) and cohort studies assess the outcomes of different OAMPs, however, these models are unlikely to ever be compared in RCTs due to the huge expense and complicated logistics required. Prognosis research provides another method of comparing outcomes of different OAMP models. This study aimed to estimate the pain and self-reported function outcomes (at 12-, 26- and 52-weeks) of people with hip and/or knee OA who participated in international OAMPs. It also aimed to describe the characteristics of OAMP participants.
Methods: This study was undertaken by members of the OARSI Joint Effort Initiative (JEI), in collaboration with the OA Trial Bank (Erasmus MC, Netherlands). RCTs and clinical cohorts assessing OAMPs were identified through the JEI membership and literature searches. Eligible studies included data from an ongoing OAMP, in any real-world setting, with participants who were diagnosed with hip or knee OA, and longitudinal measures of patient-reported pain and function. The investigators of eligible studies were invited to complete data delivery agreements with the OA Trial Bank, share individual participant data (IPD), contribute to study design and authorship. Investigators ensured they had local ethics review board approval to contribute IPD to the OA Trial bank. Each dataset was converted to a common format to enable merging into one dataset. The IPD were evaluated to convert pain and function variables to standardized scales as appropriate. Pain scores were converted to a 0-100 point scale (100 worst). Function scores were converted to a 0-100 point scale (100 best). A generalized estimating equations (GEE) model analysis was performed to assess the change in pain and function from baseline across weeks 12, 26, and 52. The model specification was based on an unstructured correlation structure and robust standard errors. Pain and function estimates were adjusted by age, sex and body mass index (BMI). Data analyses were carried out using Stata 15 (StataCorp 2015) and SPSS 17.
Results: The investigators of 13 international OAMPs were invited to take part. IPD from 9 OAMPs were delivered: the OA Chronic Care Program, Ramsay Health OA Management Program, Joint Health Program, University of Wisconsin Health Knee and Hip Comprehensive Non-Surgical OA Management Clinic, Improved Management of Patients With Hip and Knee OA in Primary Health Care, Joint Academy, Amsterdam OA cohort, Management of OA In Consultations, and Collaborative model of care between Orthopaedics and allied healthcare professionals in knee OA. The characteristics of the OAMPs are summarised in table 1. The OAMPs were conducted in-person except for the Joint Academy that was implemented as an online OAMP. Individual participant data from 9819 participants were analyzed. The cohort studies were missing large amounts of data, as expected in clinical practice. The characteristics of OAMP participants are summarised in Table 2. The majority of OAMP participants reported the knee as their index joint, their mean age ranged between 62- 67 years, 58-74% were female, 25-48% were working and mean BMI indicated they were overweight at baseline. Pain was most commonly assessed using a Numeric Rating Scale or validated questionnaires e.g. the Knee Injury and OA Outcome Scale (KOOS). Function was mostly assessed using validated questionnaires such as the KOOS. The pain and fuction measured in the original datasets are reported in Table 1. The changes in pain and function of the OAMP participants from baseline across weeks 12, 26, and 52 are summarised in Table 3. There were reductions in pain scores and improvements in function scores seen across all programs at the majority of timepoints.
Conclusions: We established the first data bank of IPD from different international OAMPs. Analysis of the IPD demonstrated modest improvements in pain and function across the programs at all timepoints. The most rapid improvements were made by week-12, however, these gains were maintained at week-52. In future work this project will use IPD meta-analysis to identify prognostic factors of people with OA who participate in OAMPs.
Factor Xa (FXa) has a prominent role in amplifying both inflammation and the coagulation cascade. In the coagulation cascade, its main role is catalyzing the proteolytic activation of prothrombin to ...thrombin. Efficient proteolysis is well known to require phosphatidylserine (PS)-containing membranes that are provided by platelets in vivo. However, soluble, short-chain PS also triggers efficient proteolytic activity and formation of an inactive FXa dimer in solution. In this work, we ask whether PS-containing membranes also trigger formation of an inactive FXa dimer. We determined the proteolytic activity of human FXa toward human Pre2 as a substrate both at fixed membrane concentration (increasing FXa concentration) and at fixed FXa concentration (increasing membrane concentration). Neither of these experiments showed the expected behavior of an increase in activity as FXa bound to membranes, but instead suggested the existence of a membrane-bound inactive form of FXa. We found also that the fluorescence of fluorescein attached to FXa's active site serine was depolarized in a FXa concentration-dependent fashion in the presence of membranes. The fluorescence lifetime of FXa labeled in its active sites with a dansyl fluorophore showed a similar concentration dependence. We explained all these observations in terms of a quantitative model that takes into account dimerization of FXa after binding to a membrane, which yielded estimates of the FXa dimerization constant on a membrane as well as the kinetic constants of the dimer, showing that the dimer is effectively inactive.
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