Single wall carbon nanotubes enter cells by endocytosis and not membrane penetration

<p>Abstract</p> <p>Background</p> <p>Carbon nanotubes are increasingly being tested for use in cellular applications. Determining the mode of entry is essential to control and regulate specific interactions with cells, to understand toxicological effects of nanotubes, and to develop nanotube-based cellular technologies. We investigated cellular uptake of Pluronic copolymer-stabilized, purified ~145 nm long single wall carbon nanotubes (SWCNTs) through a series of complementary cellular, cell-mimetic, and in vitro model membrane experiments.</p> <p>Results</p> <p>SWCNTs localized within fluorescently labeled endosomes, and confocal Raman spectroscopy showed a dramatic reduction in SWCNT uptake into cells at 4°C compared with 37°C. These data suggest energy-dependent endocytosis, as shown previously. We also examined the possibility for non-specific physical penetration of SWCNTs through the plasma membrane. Electrochemical impedance spectroscopy and Langmuir monolayer film balance measurements showed that Pluronic-stabilized SWCNTs associated with membranes but did not possess sufficient insertion energy to penetrate through the membrane. SWCNTs associated with vesicles made from plasma membranes but did not rupture the vesicles.</p> <p>Conclusions</p> <p>These measurements, combined, demonstrate that Pluronic-stabilized SWCNTs only enter cells via energy-dependent endocytosis, and association of SWCNTs to membrane likely increases uptake.</p

Single wall carbon nanotubes enter cells by endocytosis and not membrane penetration

<p>Abstract</p> <p>Background</p> <p>Carbon nanotubes are increasingly being tested for use in cellular applications. Determining the mode of entry is essential to control and regulate specific interactions with cells, to understand toxicological effects of nanotubes, and to develop nanotube-based cellular technologies. We investigated cellular uptake of Pluronic copolymer-stabilized, purified ~145 nm long single wall carbon nanotubes (SWCNTs) through a series of complementary cellular, cell-mimetic, and in vitro model membrane experiments.</p> <p>Results</p> <p>SWCNTs localized within fluorescently labeled endosomes, and confocal Raman spectroscopy showed a dramatic reduction in SWCNT uptake into cells at 4°C compared with 37°C. These data suggest energy-dependent endocytosis, as shown previously. We also examined the possibility for non-specific physical penetration of SWCNTs through the plasma membrane. Electrochemical impedance spectroscopy and Langmuir monolayer film balance measurements showed that Pluronic-stabilized SWCNTs associated with membranes but did not possess sufficient insertion energy to penetrate through the membrane. SWCNTs associated with vesicles made from plasma membranes but did not rupture the vesicles.</p> <p>Conclusions</p> <p>These measurements, combined, demonstrate that Pluronic-stabilized SWCNTs only enter cells via energy-dependent endocytosis, and association of SWCNTs to membrane likely increases uptake.</p

The Utility of Functional Movement Assessment on NBA Players

Professional basketball related injuries have not declined over the last decade despite improvements in training and conditioning or medical advancements in diagnostics, surgery, or rehabilitation. A descriptive epidemiological study of 80% of the National Basketball Association (NBA) teams over 17 years reported an injury incidence of 19.1 per 1000 athlete exposures, and 59,179 games missed due to injury. Starkey found that the there has been a 12.4% increase in game-related injuries in the NBA in a 10-year period from the 1988 - 1997 seasons. It is suspected that increased contact within the NBA along with improved player athleticism, size, power, and speed have contribute to the rise in injuries. The most commonly reported injuries in the NBA as reported via the greatest number of days missed include ankle sprains, patellofemoral inflammation, knee sprains, and lumbar strains. Recent trends involve less focus on specific physical or clinical measures and increased attention on the assessment of functional movement patterns for the purpose of predicting the likelihood of injury. The Functional Movement Screen (FMSTM) was introduced as a pre-participation examination intended to evaluate the quality of seven basic movement patterns that require a balance of both mobility and stability. The functional movements tested include: deep squat, hurdle step, in-line lunge, shoulder mobility, active straight leg raise, trunk stability push-up, and rotary stability. It is designed to assess the extremes of specific movements and positions for the purpose of identifying potential limitation, compensation, and asymmetry in individuals without obvious pathology. Recent literature has linked this screen to injury prediction in numerous populations that may be predisposed to injury, including professional football players, firefighters, collegiate female athletes, elite track and field athletes, military personnel. The majority of reliability studies conclude that the FMSTM has good intra-rater reliability. While some researchers conclude that reliability increases with additional training and clinical experience, others claim that the FMS intra-rater reliability was not improved with FMS certification. Inter- rater reliability was reported in recent studies to range from moderate and good to high. The Y-balance Test (YBT) is pre-participation assessment used to screen individuals who may have potential for lower extremity injury. This test involves the examination of dynamic balance and postural control. While research is still lacking regarding the validity and utility of the YBT-LQ, the SEBT has been reported to have a moderate to strong effect size and that this test was reliable and valid as a dynamic predictor to lower extremity injuries. No studies have investigated the outcomes of YBT as an injury predictor in professional basketball athletes or the relationship of these factors with functional movement screens.https://ecommons.udayton.edu/dpt_symposium/1011/thumbnail.jp

The Relationship between Knee Valgus and Clinical Measures in Professional Basketball: A CART Analysis

Background/Purpose: Lower extremity injuries occur at an amplified rate in professional basketball. Evidence suggests that knee frontal plane valgus may be associated with risk of injury. The Landing Error Scoring System includes the assessment of maximum knee valgus during a countermovement jump. The investigation of interactions among linear and non-linear factors may help the understanding of the interdependence of various measures and poor performance on the knee valgus displacement (KVD) component of the LESS in professional basketball players. The purpose of this study was to investigate predictors of knee valgus displacement on the LESS. We hypothesize that a positive finding on the knee valgus displacement component of the LESS will be predicted by select clinical measures. Methods: 47 professional basketball players participated. Measurements were completed as part of preseason mobility screening prior to the 2015-16 and 2016-17 NBA seasons. Classification and Regression Tree Analysis (CART) were used to investigate linear and non-linear interactions among predictors and their influence on KVD in players who performed the LESS test. Results: Of the 47 players included in this study, 16 players did not test positive for KVD on the LESS test and 31 did. Pruning resulted in 4 splits (r2=0.507) demonstrating that KVD was predicted by total hip rotation range of motion, dominant leg hip external rotation, and standing arch height index measure. Predictive modeling, classified 18 of the 31 players with KVD and 8 of the 16 players who tested negative for KVD. The area under the ROC curve was .9183, suggesting that classification of players using this model was not random. Conclusion: KVD and performance on the LESS has been linked with injury. CART analysis captured linear and non-linear interactions between clinical measures suggesting that lower extremity biomechanical factors may be associated with predicting KVD during performance on the LESS. Clinical Relevance: KVD and the LESS test has been shown to be predictive of injury. Identifying which clinical measures may be linked with poor performance on this test may aide clinicians in determining appropriate interventions that may be associated with improved scores and minimize risk of injury.https://ecommons.udayton.edu/dpt_symposium/1000/thumbnail.jp

The XMM Cluster Survey: Evidence for energy injection at high redshift from evolution of the X-ray luminosity-temperature relation

We measure the evolution of the X-ray luminosity-temperature (L_X-T) relation since z~1.5 using a sample of 211 serendipitously detected galaxy clusters with spectroscopic redshifts drawn from the XMM Cluster Survey first data release (XCS-DR1). This is the first study spanning this redshift range using a single, large, homogeneous cluster sample. Using an orthogonal regression technique, we find no evidence for evolution in the slope or intrinsic scatter of the relation since z~1.5, finding both to be consistent with previous measurements at z~0.1. However, the normalisation is seen to evolve negatively with respect to the self-similar expectation: we find E(z)^{-1} L_X = 10^{44.67 +/- 0.09} (T/5)^{3.04 +/- 0.16} (1+z)^{-1.5 +/- 0.5}, which is within 2 sigma of the zero evolution case. We see milder, but still negative, evolution with respect to self-similar when using a bisector regression technique. We compare our results to numerical simulations, where we fit simulated cluster samples using the same methods used on the XCS data. Our data favour models in which the majority of the excess entropy required to explain the slope of the L_X-T relation is injected at high redshift. Simulations in which AGN feedback is implemented using prescriptions from current semi-analytic galaxy formation models predict positive evolution of the normalisation, and differ from our data at more than 5 sigma. This suggests that more efficient feedback at high redshift may be needed in these models.Comment: Accepted for publication in MNRAS; 12 pages, 6 figures; added references to match published versio

Is Gly16Arg β₂ Receptor Polymorphism Related to Impulse Oscillometry in a Real-Life Asthma Clinic Setting?

PURPOSE: We evaluated whether Gly16Arg beta2-receptor genotype relates to impulse oscillometry (IOS) in a real-life clinic setting. METHODS: Patients with persistent asthma taking inhaled corticosteroid ± long-acting beta-agonist (ICS ± LABA) were evaluated. We compared genotype groups comprising either no Arg copies (i.e. GlyGly) versus one or two Arg copies (i.e. ArgArg or ArgGly). IOS outcomes included total airway resistance at 5 Hz (R5), central airway resistance at 20 Hz (R20), peripheral airway resistance (R5–R20), reactance at 5 Hz, area under reactance curve (AX) and resonant frequency (RF). In addition, we recorded ACQ-5 and salbutamol use. RESULTS: One hundred and twelve ICS-treated asthmatic patients (mean ICS dose 1238 µg/day), mean age 43 years, ACQ 2.34, FEV1 82 %, R5 177 % were identified—89 were also taking LABA. 61 patients were GlyGly, while 14 were ArgArg and 37 were ArgGly. There were no significant differences in IOS outcomes, ACQ or salbutamol use between the genotypes. The allelic risk (as odds ratio) for less well-controlled asthma (as ACQ > 1.5) was 1.1 (95 % CI 0.72–1.68) in relation to each Arg copy with a corresponding odds ratio for abnormal R5–R20 > 0.07kPA/l.s being 0.91 (95 % CI 0.57–1.44). 71 % of patients had an ACQ > 1.5 in the GlyGly group, versus 67 % in GlyArg/ArgArg group, with corresponding figures for abnormal R5–R20 > 0.07 kPa/l.s being 69 versus 73 %. CONCLUSION: In a real-life clinic setting for patients with poorly controlled persistent asthma taking ICS ± LABA, we found no evidence of any relationship of Gly16Arg to IOS, ACQ or salbutamol use

Cardiovascular events after clarithromycin use in lower respiratory tract infections:analysis of two prospective cohort studies

Objective: To study the association of clarithromycin with cardiovascular events in the setting of acute exacerbations of chronic obstructive pulmonary disease and community acquired pneumonia.Design: Analysis of two prospectively collected datasets.Setting: Chronic obstructive pulmonary disease dataset including patients admitted to one of 12 hospitals around the United Kingdom between 2009 and 2011; Edinburgh pneumonia study cohort including patients admitted to NHS Lothian Hospitals between 2005 and 2009.Population: 1343 patients admitted to hospital with acute exacerbations of chronic obstructive pulmonary disease and 1631 patients admitted with community acquired pneumonia.Main outcome measures: Hazard ratios for cardiovascular events at one year (defined as hospital admissions with acute coronary syndrome, decompensated cardiac failure, serious arrhythmia, or sudden cardiac death) and admissions for acute coronary syndrome (acute ST elevation myocardial infarction, non-ST elevation myocardial infarction, and unstable angina). Secondary outcomes were all cause and cardiovascular mortality at one year.Results: 268 cardiovascular events occurred in the acute exacerbations of chronic obstructive pulmonary disease cohort and 171 in the community acquired pneumonia cohort over one year. After multivariable adjustment, clarithromycin use in acute exacerbations of chronic obstructive pulmonary disease was associated with an increased risk of cardiovascular events and acute coronary syndrome—hazard ratios 1.50 (95% confidence interval 1.13 to 1.97) and 1.67 (1.04 to 2.68). After multivariable adjustment, clarithromycin use in community acquired pneumonia was associated with increased risk of cardiovascular events (hazard ratio 1.68, 1.18 to 2.38) but not acute coronary syndrome (1.65, 0.97 to 2.80). The association between clarithromycin use and cardiovascular events persisted after matching for the propensity to receive clarithromycin. A significant association was found between clarithromycin use and cardiovascular mortality (adjusted hazard ratio 1.52, 1.02 to 2.26) but not all cause mortality (1.16, 0.90 to 1.51) in acute exacerbations of chronic obstructive pulmonary disease. No association was found between clarithromycin use in community acquired pneumonia and all cause mortality or cardiovascular mortality. Longer durations of clarithromycin use were associated with more cardiovascular events. Use of β lactam antibiotics or doxycycline was not associated with increased cardiovascular events in patients with acute exacerbations of chronic obstructive pulmonary disease, suggesting an effect specific to clarithromycin.Conclusions: The use of clarithromycin in the setting of acute exacerbations of chronic obstructive pulmonary disease or community acquired pneumonia may be associated with increased cardiovascular events. These findings require confirmation in other datasets

Drug-repositioning screens identify Triamterene as a selective drug for the treatment of DNA Mismatch Repair deficient cells.

Purpose: The DNA Mismatch repair (MMR) pathway is required for the maintenance of genome stability. Unsurprisingly, mutations in MMR genes occur in a wide range of different cancers. Studies thus far have largely focused on specific tumor types or MMR mutations, however it is becoming increasingly clear that a therapy targeting MMR-deficiency in general would be clinically very beneficial. Experimental Design: Based on a drug-repositioning approach, we screened a large panel of cell lines with various MMR deficiencies from a range of different tumor types with a compound drug library of previously approved drugs. We have identified the potassium-sparing diuretic drug Triamterene, as a novel sensitizing agent in MMR-deficient tumor cells, in vitro and in vivo. Results: The selective tumor cell cytotoxicity of Triamterene occurs through its antifolate activity, and depends on the activity of the folate synthesis enzyme, thymidylate synthase. Triamterene leads to a thymidylate synthase-dependent differential increase in reactive oxygen species in MMR-deficient cells, ultimately resulting in an increase in DNA double strand breaks. Conclusion: Conclusively, our data reveal a new drug repurposing and novel therapeutic strategy that has potential for the treatment of MMR-deficiency in a range of different tumor types and could significantly improve patient survival

Project Report No. PR640-02: Optimal grazing management to enhance soil biodiversity and soil carbon in upland grassland

Here we report on a project instigated by and co-designed with a group of livestock farmers in Wales who wanted to know more about the health and sustainability of their grassland soils. The core aim of the project was to enhance the sustainability and resilience of livestock production relying on grassland whilst maintaining ecosystem services such as carbon sequestration and biodiversity provision. Soil carbon and nitrogen content and soil biodiversity measurements were obtained to determine whether these were being impacted by grazing management. The farmers were interviewed to determine the role of soil health in decision making as well as how best to communicate complex science evidence

Undetectable Measurable Residual Disease Is Associated With Improved Outcomes in AML Irrespective of Treatment Intensity

Acute myeloid leukemia (AML) can be treated with either high- or low-intensity regimens. Highly sensitive assays for measurable residual disease (MRD) now allow for a more precise assessment of response quality. We hypothesized that treatment (Rx) intensity may not be a key predictor of outcomes, assuming that an optimal response to therapy is achieved. We performed a single-center retrospective study including 635 patients with newly diagnosed AML responding to either intensive cytarabine/anthracycline-based chemotherapy (IA; n = 385) or low-intensity venetoclax-based regimens (LOW + VEN; n = 250) and who had adequate flow cytometry-based MRD testing performed at the time of best response. The median overall survival (OS) was 50.2, 18.2, 13.6, and 8.1 months for the IA MRD-, LOW + VEN MRD-, IA MRD+, and LOW + VEN MRD+ cohorts, respectively. The 2-year cumulative incidence of relapse (CIR) was 41.1%, 33.5%, 64.2%, and 59.9% for the IA MRD-, LOW + VEN MRD-, IA MRD+, and LOW + VEN MRD+ cohorts, respectively. The CIR was similar between patients within MRD categories irrespective of the treatment regimen received. The IA cohort was enriched for younger patients and favorable AML cytogenetic/molecular categories. Using multivariate analysis, age, best response (complete remission [CR]/CR with incomplete hematologic recovery/morphologic leukemia-free state), MRD status, and European LeukemiaNet (ELN) 2017 risk remained significantly associated with OS, whereas best response, MRD status, and ELN 2017 risk were significantly associated with CIR. Treatment intensity was not significantly associated with either OS or CIR. Achievement of MRD- CR should be the key objective of AML therapy in both high- and low-intensity treatment regimens