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Objective: Mobile low-dose computed tomography (LDCT) lung screenings are part of an outreach program in rural Appalachia to detect early lung cancer. Coronary artery calcium (CAC) scoring on LDCT can identify calcium deposits in coronary arteries and can prompt consideration of risk modification for prevention of cardiovascular disease (CVD) events. It is not known if Lung CT Screening Reporting & Data System (Lung-RADS) scoring correlates with CAC scores. There is no clear guidance for patients undergoing LDCT screenings to receive follow-up regarding CAC or prevention of associated CVD risk. Methods: This was a retrospective review of mobile LDCT LCS in adults with no known history of CVD. CT images were obtained at 100 kVp with a slice thickness of 3 mm. Agatston CAC scoring was performed retroactively. Lung-RADS scores were categorized as: Negative (1), Benign (2), Probably Benign (3), and Suspicious (4). CAC scoring was grouped as 0, 1–100, 101–399, and ≥400. Descriptive statistics and chi-square analyses were utilized. Results: A total of 526 LDCT screenings were included. Over 54 % of patients had coronary calcification on LDCT LCS. 161 patients (30.6 %) had a CAC score of ≥100 and 75 patients (14.3 %) had a CAC score ≥400. Of patients with a CAC score ≥100, 7.5 % received referrals for follow-up after the LDCT screen and 9.3 % had additional cardiac testing. Of those with a CAC score ≥100 not already on a statin (45.3 %) and not already on aspirin (63.3 %), few were started within 3 months of LDCT for prevention (8.2 % and 5.9 % respectively). Among patients with a Lung-RADS score of 4, 17 % had a CAC score >400, whereas only 12 % with a Lung-RADS score of 1 fell into the same CAC category. Higher Lung-RADS scores correlated with fewer patients with CAC of 0. A significant correlation was observed between higher Lung-RADS scores and elevated CAC scores (p = 0.02). Conclusion: In patients with no CVD history, coronary artery calcification was frequently identified on mobile LDCT lung screenings in rural communities. Patients with higher probabilities of malignant lung nodules may also be at increased risk for significant coronary artery disease. Calcium scoring from LDCT screenings allowed for simultaneous assessment of lung cancer and CVD risk. Unfortunately, few referrals or CVD prevention medications were initiated. Awareness of CAC score utility, follow-up for identified coronary calcifications, and consideration of primary prevention medications when indicated, would be beneficial in patients undergoing LDCT lung screenings, especially in rural areas with limited healthcare access.

Abstract Declining Arctic sea ice over recent decades has been linked to growth in coastal hazards affecting the Alaskan Arctic. In this study, climate model projections of sea ice are utilized in the simulation of an extratropical cyclone to quantify how future changes in seasonal ice coverage could affect coastal waves caused by this extreme event. All future scenarios and decades show an increase in coastal wave heights, demonstrating how an extended season of open water in the Chukchi and Beaufort Seas could expose Alaskan Arctic shorelines to wave hazards resulting from such a storm event for an additional winter month by 2050 and up to three additional months by 2070 depending on climate pathway. Additionally, for the Beaufort coastal region, future scenarios agree that a coastal wave saturation limit is reached during the sea ice minimum, where historically sea ice would provide a degree of protection throughout the year.

Niacin, an important component of a balanced diet, is central to lipid metabolism. Occasionally used to treat hyperlipidemia, niacin is widely available without a prescription, making its use often unknown to treating physicians. Severe hepatotoxicity has been reported with niacin use. In the following report, we describe a case of hospitalization for acute decompensated cirrhosis with cholestatic morphology in a patient taking self-initiated large quantities of extended-release niacin. Despite medical management and support, the patient unfortunately expired on day 16 of hospitalization. Given ease of access and unclear long-term benefit in hyperlipidemia, the current case serves to raise awareness of niacin’s potential hepatotoxicity through highlighting a severe outcome. Although mode of liver injury remains unknown, the use of extended-release niacin formulations and prolonged high-dose supplementation is associated with enhanced hepatotoxicity. Careful review and counseling of commonly available supplements remains an important task of both hospital and primary care physicians.

Objective: To identify and map the extent to which trials for pain interventions in individuals with knee osteoarthritis (OA) track measures of sleep, characterize the type of sleep measure assessed, and assess their influence on pain-related effect sizes. Design: A scoping review was conducted, searching seven bibliometric databases from 2000 to 2022. We included all randomized controlled trials with a primary purpose of assessing non-surgical pain management interventions for adults with knee OA. All non-surgical interventions and any comparator or control were included. Demographic data were pooled from all trials. Results: 926 trials conducted in 61 countries met eligibility. Nineteen trials (2.1%) recorded some form of sleep assessment. Eleven trials (1.2%) assessed a formal index of sleep disturbance collected at multiple time points. No trials formally assessed the influence of sleep on the primary pain outcome (e.g., as a potential mediator), nor met the most recent guidelines for core data element recommendations regarding sleep assessment. Conclusion: This review highlights the paucity of sleep data captured and reported in randomized controlled trials for knee OA. The vast majority of trials addressing symptomatic knee OA do not capture sleep measures, significantly limiting the ability to accurately determine an intervention's effect on pain. Future research should include formal sleep-centric assessments measured at multiple time points to analyze sleep dysfunction and its relationship on treatment effects.

The observed retreat and anticipated further decline in Arctic sea ice holds strong climate, environmental, and societal implications. In predicting climate evolution, ensembles of coupled climate models have demonstrated appreciable accuracy in simulating sea-ice area trends throughout the historical period, yet individual climate models still show significant differences in accurately representing the sea-ice thickness distribution. To better understand individual model performance in sea-ice simulation, nine climate models were evaluated in comparison with Arctic satellite and reanalysis-derived sea-ice thickness data, sea-ice area records, and atmospheric reanalysis data of surface wind and air temperature. This assessment found that the simulated spatial distribution of historical sea-ice thickness varies greatly between models and that several key limitations persist among models. Primarily, most models do not capture the thickest regimes of multiyear ice present in the Wandel and Lincoln seas; those that do often possess erroneous positive bias in other regions such as the Laptev Sea or along the Eurasian Arctic Shelf. This analysis provides enhanced understanding of individual model historical simulation performance, which is critical in informing the selection of coupled climate model projections for dependent future modeling efforts.

Abstract Background Ibrutinib is a Bruton’s tyrosine kinase inhibitor used in the treatment of hematological malignancies. The most common cardiotoxicity associated with ibrutinib is atrial arrhythmia (atrial fibrillation and flutter). It is known that patients with cardiovascular disease (CVD) are at an increased risk for developing atrial arrhythmia. However, the rate of atrial arrhythmia in patients with pre-existing CVD treated with ibrutinib is unknown. Objective This study examined whether patients with pre-existing CVD are at a higher risk for developing atrial arrhythmias compared to those without prior CVD. Methods A single-institution retrospective chart review of patients with no prior history of atrial arrhythmia treated with ibrutinib from 2012 to 2020 was performed. Patients were grouped into two cohorts: those with CVD (known history of coronary artery disease, heart failure, pulmonary hypertension, at least moderate valvular heart disease, or device implantation) and those without CVD. The primary outcome was incidence of atrial arrhythmia, and the secondary outcomes were all-cause mortality, risk of bleeding, and discontinuation of ibrutinib. The predictors of atrial arrhythmia (namely atrial fibrillation) were assessed using logistic regression. A Cox-Proportional Hazard model was created for mortality. Results Patients were followed for a median of 1.1 years. Among 217 patients treated with ibrutinib, the rate of new-onset atrial arrhythmia was nearly threefold higher in the cohort with CVD compared to the cohort without CVD (17% vs 7%, p = 0.02). Patients with CVD also demonstrated increased adjusted all-cause mortality (OR 1.9, 95% CI 1.06-3.41, p = 0.01) and decreased survival probability (43% vs 54%, p = 0.04) compared to those without CVD over the follow-up period. There were no differences in risk of bleeding or discontinuation between the two cohorts. Conclusions Pre-existing cardiovascular disease was associated with significantly higher rates of atrial arrhythmia and mortality in patients with hematological malignancies managed with ibrutinib.

Abstract Much of the United States Atlantic coastline continues to undergo subsidence due to post glacial settlement and ground water depletion. Combined with eustatic sea level rise (SLR), this contributes to an increased rate of relative SLR. In this work, we utilize the ADvanced CIRCulation model to project storm surges across coastal North Carolina. Recent hurricanes Irene and Matthew are simulated considering SLR and subsidence estimates for 2100. Relative to present day conditions, storm surge susceptible regions increase by 27% (Irene) to 40% (Matthew) due to subsidence. Combined with SLR (+ 74 cm), results suggest more than a doubling of areal flood extent for Irene and more than a three-fold increase for Hurricane Matthew. Considering current regional population distributions, this translates to an increase in at-risk populations of 18% to 61% due to subsidence. Even further, exposed populations are projected to swell relative to Matthew and Irene baseline simulations (8200 and 28,500) by more than 70,000 in all SLR scenarios (79,400 to 133,600). While increases in surge inundation are driven primarily by SLR in the region, there remains a substantial contribution due to vertical land movement. This outlines the importance of exploring spatially variable land movement in surge prediction, independent of SLR.

Abstract Background Internet Gaming Disorder (IGD) behaviours involve excessive use of Internet games to the extent that one’s everyday life is compromised. It has been suggested that IGD symptoms are dependent on whether one is more individualistic or collectivistic. However, the range of potential individualism-collectivismeffects on IGD presentations remains largely unknown. The current study aims to further understanding of the role of individualistic and collectivistic tendencies in IGD, allowing us to develop more gamer centredIGD prevention and intervention strategies. Methods One thousand and thirty-twocommunity participants withinternet gaming experience were measured online for IGD symptom’s severity using the Internet Gaming Disorder Scale – Short Form (IGDS9-SF) andindividualism-collectivism behavioursvia the Individualism & Collectivism Scale (ICS). Latent Class Analysis (LCA) and T-Tests were performed in relation to their responses. Results Upon inspection of the LCA output, two profiles of internet gamers were identified. These includedthe Collectivism Aversivegamers (CA; 11%) and the Collectivism Neutral gamers (CN; 89%). The CA gamers displayed significantly higher IGD behaviours overall, and, were higher inpreoccupation, withdrawal symptoms, tolerance, relapse, deception, escapism/mood modification, and functional impairment compared to CN gamers. There were no differences between CA and CN gamers in loss of interest and conflicts with others. Conclusions The findings suggest that one’s individualism-collectivism orientation can influence the presentation of IGD. Specifically, those who are less collectivistic or are less influenced by social groups willdisplay greater IGD symptoms and present a profile that requires a different intervention from gamers who are more collectivistic. Researchers and clinicians should emphasize the value of belonging in a collective and experiencing equality with others in relation to mental health and gaming patterns.

Background: This study aimed to investigate the role of circulating tumor cells (CTCs) and circulating cancer stem-like cells (cCSCs) before and after one cycle of chemotherapy and assessed the effects of early changes in CTCs and cCSCs on the outcomes of patients with metastatic breast cancer. Methods: Patients with stage IV invasive ductal carcinoma of the breast who received first-line chemotherapy between April 2014 and January 2016 were enrolled. CTCs and cCSCs were measured before the first cycle of chemotherapy (baseline) and on day 21, before the second cycle of chemotherapy commenced; a negative selection strategy and flow cytometry protocol were employed. Results: CTC and cCSC counts declined in 68.8 and 45.5% of patients, respectively. Declines in CTCs and cCSCs following the first chemotherapy cycle were associated with superior chemotherapy responses, longer progression-free survival (PFS), and longer overall survival (OS). An early decline in cCSCs remained an independent prognostic indicator for OS and PFS in multivariate analysis. Conclusions: A cCSC decline after one cycle of chemotherapy for metastatic breast cancer is predictive of a superior chemotherapy response and longer PFS and OS, implying that cCSC dynamic monitoring may be helpful in early prediction of treatment response and prognosis.

Introduction Ophthalmology education has been underemphasized in medical school curricula despite the fact that patient eye-related complaints are commonplace across primary care specialties. Although previous curricula used direct ophthalmoscopy to teach medical students the fundamentals of ophthalmic examination, there has been a growing call to teach these fundamentals through reading fundus photos due to the increasing prevalence and decreased costs of fundus cameras in primary care settings. We developed a virtual workshop to teach ophthalmoscopy to medical students using fundus photography. Methods First-year medical students were enrolled in a 2-hour, synchronous, virtual ophthalmoscopy workshop as part of an advanced physical exam curriculum at the University of Pittsburgh School of Medicine. Students participated in a pretest, introductory lecture, interactive small-group session, and posttest. Breakout groups were led by senior medical students or residents. We compared pre- and posttest results for improved understanding of concepts covered in the workshop. Results Of 147 students, the average scores on the pretest and posttest were 39% and 75%, respectively (p < .01). Students were significantly more confident in their ability to identify various pathologies on fundus photography. After the workshop, the student preceptors indicated increased comfort in a teaching role and greater interest in medical education. The preceptors were also more confident in their own ability to interpret fundus photography and in their understanding of various ocular pathologies. Discussion Our virtual, interactive workshop is effective in teaching medical students a systematic approach to the interpretation of fundus photographs.

Coastal flooding operational forecasting in the US is limited to short-range temporal scales (3–7 days), which limits the response time for emergency preparation and planning. The sub-seasonal prediction project (SubX), which produces weather forecasts with a lead time of up to four weeks, provides an opportunity to assess the potential for creating probabilistic flood forecasts with longer lead times. Using the ADCIRC hydrodynamic model for coastal storm surge, two major hurricanes, Isabel (2003) and Katrina (2005), were used as case studies to test coastal flood predictions induced by wind and pressure fields generated from five global weather models within SubX. The storm surges simulations are forced by Sea Level Pressure (SLP) and 10 m winds fields from SubX models for a lead-time of up to 30 days before storm landfall. The subseasonal surge forecasts are evaluated temporally and spatially at 1–4 weeks lead-time against the NOAA tide gages observations and a verification dataset derived by forcing the storm surge model with wind and pressure fields from the NCEP-Reanalysis. The results are evaluated in terms of lead-time and forecast skill metrics. The storm surge forecast skill is measured using the mean square error skill score (MSESS) relative to the verification dataset and an approximate of the climatology. A skill score greater than 0.55 is considered here useful for flood forecasting. The multi-model ensemble (MME) mean surge forecasts driven by several members of SubX models demonstrate skill greater than 0.55 up to a 4-day and 10-day lead for Katrina and Isabel, respectively. A sharper decrease in MSESS was noted from week 1 to week 3 lead-times for Katrina, in comparison to Isabel. Some ensemble members forecasted hurricanes and storm surges as early as 3–4 weeks lead-time. However, due to the offsets developed in the timing and magnitude of the peak at these lead-times, and based on a sample size of only two events, it is hard to establish the significance of these longer lead-time results. While a follow up study involving flood reforecasts over the entire SubX reforecast period (1999–2015) is needed to support more robust statistics of the forecast skill, our case studies demonstrate the feasibility of probabilistic flood forecasting at subseasonal timescales using the SubX models.

Inflammatory bowel disease (IBD) is a chronic ailment afflicting millions of people worldwide, with the majority of recognized cases within industrialized countries. The impacts of IBD at the individual level are long-lasting with few effective treatments available, resulting in a large burden on the health care system. A number of existing animal models are utilized to evaluate novel treatment strategies. Two commonly used models are (1) acute colitis mediated by dextran sulphate sodium (DSS) treatment of wild-type mice and (2) chronic colitis mediated by the transfer of proinflammatory T cells into immunodeficient mice. Despite the wide use of these particular systems to evaluate IBD therapeutics, the typical readouts of clinical disease progression vary depending on the model used, which may be reflective of mechanistic differences of disease induction. The most reliable indicator of disease in both models remains intestinal damage which is typically evaluated upon experimental endpoint. Herein, we evaluated the expression profile of a panel of cytokines and chemokines in both DSS and T cell transfer models in an effort to identify a number of inflammatory markers in the blood that could serve as reliable indicators of the relative disease state. Out of the panel of 25 markers tested, 6 showed statistically significant shifts with the DSS model, compared to 11 in the T cell transfer model with IL-6, IL-13, IL-22, TNF-α and IFN-γ being common markers of disease in both models. Our data highlights biological differences between animal models of IBD and helps to guide future studies when selecting efficacy readouts during the evaluation of experimental IBD therapeutics.

Abstract Background Circulating tumor cells (CTCs) are associated with breast cancer prognosis. Research is limited regarding the role of circulating cancer stem-like cells (cCSCs) considering the treatment response and survival among patients with metastatic breast cancer. Accordingly, we performed this prospective study to clarify the prognostic significance of baseline cCSCs for metastatic breast cancer in terms of first-line chemotherapy. Methods Between April 2014 and January 2016, we prospectively enrolled 48 patients with stage IV breast invasive ductal carcinoma who underwent first-line chemotherapy. We identified and analyzed CTCs and cCSCs by using a protocol based on negative selection and flow cytometry before chemotherapy. CTCs were identified as EpCAM+Hoechst+CD45– cells and cCSCs as CD133+EpCAM+Hoechst+CD45– cells. cCSCs were expressed as a percentage of CTCs. The associations between CTCs, cCSCs, and the clinicopathological variables that were predictive of the treatment response and survival outcome were analyzed using univariate and multivariate analyses. Results We identified CTCs in all the enrolled patients, with a median number of 33.9/mL CTCs. CSCs were isolated in 97.9% of the patients; the median percentage of cCSCs was 14.7%. A high baseline level of cCSCs was correlated with an inferior tumor response rate (54.2% vs. 95.8%, p

Abstract The ShUREX (Shigaraki UAV Radar Experiment) 2015 campaign carried out at the Shigaraki Middle and Upper atmosphere (MU) observatory (Japan) in June 2015 provided a unique opportunity to compare vertical profiles of atmospheric parameters estimated from unmanned aerial vehicle (UAV), balloon, and radar data in the lower troposphere. The present work is intended primarily as a demonstration of the potential offered by combination of these three instruments for studying the small-scale structure and dynamics in the lower troposphere. Here, we focus on data collected almost simultaneously by two instrumented UAVs and two meteorological balloons, near the MU radar operated continuously during the campaign. The UAVs flew along helical ascending and descending paths at a nearly constant horizontal distance from the radar (~ 1.0 km), while the balloons launched from the MU radar site drifted up to ~ 3–5 km in the altitude range of comparisons (~ 0.5 to 4.0 km) due to wind advection. Vertical profiles of squared Brünt-Väisälä frequency N 2 and squared vertical gradient of generalized potential refractive index M 2 were estimated at a vertical resolution of 20 m from pressure, temperature, and humidity data collected by UAVs and radiosondes. Profiles of M 2 were also estimated from MU radar echo power at vertical incidence at a vertical sampling of 20 m and various time resolutions (1–4 min). The balloons and the MU radar provided vertical profiles of wind and wind shear S so that two independent estimates of the gradient Richardson number (Ri = N 2/S 2) could be obtained at a range resolution of 150 m. The two estimates of Ri profiles also showed remarkable agreement at all altitudes. We show that all three instruments detected the same prominent temperature and humidity gradients, down to decameter scales in stratified conditions. These gradients extended horizontally over a few kilometers at least and persisted for hours without significant changes, indicating that the turbulent diffusion was weak. Large discrepancies between N 2and M 2 profiles derived from the balloon, UAV, and radar data were found in a turbulent layer generated by a Kelvin-Helmholtz (KH) shear flow instability in the height range from 1.80 to 2.15 km. The cause of these discrepancies appears to depend on the stage of the KH billows.

Abstract The Shigaraki unmanned aerial vehicle (UAV)-Radar Experiment (ShUREX) is an international (USA-Japan-France) observational campaign, whose overarching goal is to demonstrate the utility of small, lightweight, inexpensive, autonomous UAVs in probing and monitoring the lower troposphere and to promote synergistic use of UAVs and very high frequency (VHF) radars. The 2-week campaign lasting from June 1 to June 14, 2015, was carried out at the Middle and Upper Atmosphere (MU) Observatory in Shigaraki, Japan. During the campaign, the DataHawk UAV, developed at the University of Colorado, Boulder, and equipped with high-frequency response cold wire and pitot tube sensors (as well as an iMET radiosonde), was flown near and over the VHF-band MU radar. Measurements in the atmospheric column in the immediate vicinity of the radar were obtained. Simultaneous and continuous operation of the radar in range imaging mode enabled fine-scale structures in the atmosphere to be visualized by the radar. It also permitted the UAV to be commanded to sample interesting structures, guided in near real time by the radar images. This overview provides a description of the ShUREX campaign and some interesting but preliminary results of the very first simultaneous and intensive probing of turbulent structures by UAVs and the MU radar. The campaign demonstrated the validity and utility of the radar range imaging technique in obtaining very high vertical resolution (~20 m) images of echo power in the atmospheric column, which display evolving fine-scale atmospheric structures in unprecedented detail. The campaign also permitted for the very first time the evaluation of the consistency of turbulent kinetic energy dissipation rates in turbulent structures inferred from the spectral broadening of the backscattered radar signal and direct, in situ measurements by the high-frequency response velocity sensor on the UAV. The data also enabled other turbulence parameters such as the temperature structure function parameter CT2 $$ {C}_T^2 $$ and refractive index structure function parameter Cn2 $$ {C}_n^2 $$ to be measured by sensors on the UAV, along with radar-inferred refractive index structure function parameter Cn,radar2 $$ {C}_{n,\mathrm{radar}}^2 $$. The comprehensive dataset collected during the campaign (from the radar, the UAV, the boundary layer lidar, the ceilometer, and radiosondes) is expected to help obtain a better understanding of turbulent atmospheric structures, as well as arrive at a better interpretation of the radar data.

Acute kidney injury is a reversible medical condition commonly caused by nephrotoxic agents. The infrequency that a nebulized medication elicits a renal insult presents a rare diagnostic challenge. Within this case, we report a 57-year-old cystic fibrosis patient with chronic kidney disease (CKD) Stage G3b (baseline 1.5–1.6 mg/dL) who developed an acute kidney injury (AKI) with a serum creatinine elevation to 4.08 mg/dL and associated worsening vestibular dysfunction related to twice-daily nebulized tobramycin inhalation solution (TIS). The patient was found to have a tobramycin serum level of 4.2 μg/mL 2.5 h after TIS dosing, with elevation remaining present at 1.1 μg/mL 24 h after discontinuation of therapy. Laboratory values at one month continued to show elevated creatinine levels at 2.1 mg/dL, suggesting progression of his baseline CKD. This case supports the benefit of obtaining tobramycin serum levels and vestibular/audiology function testing when evaluating patients on chronic nebulized TIS who present with acute or chronic renal dysfunction. From these serum levels, adjustments to daily dosing, regular monitoring of tobramycin serum levels, or discontinuation of treatment should be made to prevent permanent renal damage in patients with CKD. Calculated Naranjo ADR Probability Scale: 9; Definite.

Assessing the accuracy of nearshore numerical models—such as SWAN—is important to ensure their effectiveness in representing physical processes and predicting flood hazards. In particular, for application to coastal wetlands, it is important that the model accurately represents wave attenuation by vegetation. In SWAN, vegetation might be implemented either implicitly, using an enhanced bottom friction; or explicitly represented as drag on an immersed body. While previous studies suggest that the implicit representation underestimates dissipation, field data has only recently been used to assess fully submerged vegetation. Therefore, the present study investigates the performance of both the implicit and explicit representations of vegetation in SWAN in simulating wave attenuation over a natural emergent marsh. The wave and flow modules within Delft3D are used to create an open-ocean model to simulate offshore wave conditions. The domain is then decomposed to simulate nearshore processes and provide the boundary conditions necessary to run a standalone SWAN model. Here, the implicit and explicit representations of vegetation are finally assessed. Results show that treating vegetation simply as enhanced bottom roughness (implicitly) under-represents the complexity of wave-vegetation interaction and, consequently, underestimates wave energy dissipation (error > 30%). The explicit vegetation representation, however, shows good agreement with field data (error < 20%).

An error in computing the spectral level from time series data from UAV-borne sensors was discovered after this article (Kantha et al. 2017) was published.

The asymmetric unit of the title salt, C12H14N22+·2C7H3N2O6−, comprises half a 4-[2-(pyridin-1-ium-4-yl)ethyl]pyridin-1-ium dication, being disposed about a centre of inversion, and a 2,6-dinitrobenzoate anion, in a general position. In the anion, the carboxylate group is inclined to the benzene ring [dihedral angle = 85.45 (9)°], whereas near-coplanar and twisted arrangements are found for the nitro groups [O—N—C—C torsion angles = 179.80 (14) and 20.2 (2)°]. In the crystal, three-component aggregates sustained by charge-assisted N+—H...O− hydrogen bonds are found and these are consolidated into a three-dimensional architecture by C—H...O and π–π [inter-centroid distances = 3.6796 (14) and 3.7064 (14) Å] interactions.

The asymmetric unit of title co-crystal, C14H16N4S22+·2C7H3N2O6−·4C7H4N2O6, comprises a centrosymmetric dipyridinium dication, a 2,6-dinitrobenzoate anion and two independent 2,6-dinitrobenzoic acid molecules. The pyridinium rings are each approximately perpendicular to the central dithioamide unit [dihedral angle = 80.67 (12)°]. The carboxylate/carboxylic acid groups are approximately perpendicular to the benzene ring to which they are attached [dihedral angles = 78.85 (16), 81.46 (19) and 71.28 (15)°]. By contrast, the major twist exhibited by a nitro group is manifested in a dihedral angle of 32.66 (17)°. The most prominent feature of the crystal packing is linear supramolecular chains along [1-10], featuring O—H...O(carboxylate) and pyridinium-N—H...O hydrogen bonds. These are consolidated into a three-dimensional architecture by thioamide–nitro N—H...O, C—H...O and π–π [inter-centroid distance = 3.524 (2) Å] interactions. One of the nitro O atoms was refined over two sites; the major site was 0.65 (7) occupied.

The asymmetric unit of the title co-crystal, C14H14N4S2·C14H10O4S2, comprises a twisted 2,2′-(disulfanediyl)dibenzoic acid molecule [dihedral angle between the benzene rings = 83.53 (14)°] and a U-shaped molecule of N,N′-bis(4-pyridylmethyl)ethanedithioamide in which intramolecular N—H...S hydrogen bonds are observed. Two molecules of each form a centrosymmetric ring, with an extended chair conformation, mediated by carboxyl–pyridine O—H...N hydrogen bonds between the carboxylic acid groups of two 2,2′-(disulfanediyl)dibenzoic acid molecules and pyridine-N atoms of two N,N'-bis(4-pyridylmethyl)ethanedithioamide molecules. The tetrameric aggregates are linked into a supramolecular chain along the b axis via amide–carbonyl N—H...O hydrogen bonds.

The asymmetric unit of the polymeric title salt, {[Ag(C5H5NO)2]PF6}n, comprises an AgI cation (located on a twofold axis), two 2-pyridone ligands (with distinct coordination modes), and half a PF6− anion (situated on a centre of inversion). The AgI atom is in an approximately octahedral AgO6 coordination geometry, which is stabilized by intramolecular N—H...O hydrogen bonds. The result of the bridging mode of the 2-pyridone ligand is the formation of a supramolecular chain along the c axis; these are consolidated in the crystal by C—H...F interactions.

In the title salt, [Ag2(CF3CO2)2(C10H8N2)]n, which may also be regarded as a coordination polymer if long Ag...O interactions are considered, each of the N atoms of the somewhat twisted 2,2′-bipyridine molecule [N—C—C—N = −27.5 (4)°] binds to an Ag atom, and each of the carboxylate ligands is tridentate, linking to three Ag atoms. The bidentate carboxylate O atoms bridge the same two Ag atoms, resulting in the formation of Ag2O2 rings. These rings are bridged by the 2,2′-bipyridine ligands, forming a chain along the b axis. The chains are linked into double chains via the remaining Ag—O bonds and Ag...Ag contacts. As a consequence of the Ag...Ag contacts, the NO4 donor set about each Ag atom is heavily distorted. Finally, the chains are linked into a three-dimensional network by a combination of C—H...O and C—H...F interactions.

In the title compound, [Ag(CF3SO3)(C8H10N4O2)2(H2O)], the AgI atom is coordinated by two caffeine N atoms and, at longer distances, two O atoms of a coordinated water molecule and the trifluoromethanesulfonate anion, resulting in an AgN2O2 seesaw geometry. The caffeine molecules are roughly coplanar [dihedral angle = 5.81 (5)°]. In the crystal, molecules self-assemble into a linear supramolecular chain along the c axis via O—H...O hydrogen bonds involving the coordinated water moledcule and carbonyl O atoms. The packing is consolidated by weak C—H...O interactions.

The asymmetric unit of the title salt, [Ag(C14H14N4O2)1.5](CF3SO3), comprises a Ag+ cation, three half-molecules of N,N′-bis(2-pyridylmethyl)oxalamide (each of which is disposed about a centre of inversion) and a trifluoromethanesulfonate anion. Distinct coordination modes are found for the bridging ligands, i.e., a μ2,κ2-bridging mode involving pyridine N atoms for one ligand, and a μ2,κ4-bridging mode, employing both pyridine N and amide O atoms for the remaining ligands. The Ag+ cations, which are in a distorted square-pyramidal coordination, and the ligands combine to form a two-dimensional array parallel to (101); these arrays are connected into a three-dimensional structure by trifluoromethanesulfonate anions via N—H...O, C—H...O, and C—F...O interactions.

The asymmetric unit of the title co-crystal, 2C13H10N2O3·C14H14N4O2, comprises one molecule of 2-(4-hydroxyphenyldiazenyl)benzoic acid and half of an N,N′-bis(4-pyridylmethyl)oxamide molecule as the latter is disposed about an inversion centre. The most notable feature of the crystal structure is the formation of supramolecular chains arising from hydroxy–pyridine O—H...N contacts and amide–hydroxy C—H...O contacts. These give rise to 40-membered {...OH...NNC4OH...NC4NC2NH}2 synthons, generating supramolecular chains along [01overline{1}]. The chains are connected into a two-dimensional array via C—H...π interactions. Layers, with a step-ladder topology, are consolidated into the crystal structure via further C—H...π interactions.

In the title molecular salt, C7H11N2+·C13H9N2O3−, the dihedral angle between the benzene rings in the anion is 35.14 (8)°. In the crystal, centrosymmetrically related anions associate via hydroxyl–carboxylate O—H...O hydrogen bonds, resulting in a 24-membered {...OC3N2C4OH}2 synthon. The cations are associated with this dimeric unit via pyridinium–carboxylate N—H...O hydrogen bonds. Weak C—H...O links further consolidate the packing, generating layers.

Atracotoxins are novel peptide toxins from the venom of Australian funnel-web spiders that slow sodium current inactivation in a similar manner to scorpion alpha-toxins. To analyse their interaction with known sodium channel neurotoxin receptor sites we determined their effect on scorpion toxin, batrachotoxin and saxitoxin binding. Nanomolar concentrations of delta-atracotoxin-Hv1 and delta-atracotoxin-Ar1 completely inhibited the binding of the scorpion alpha-toxin AaH II to rat brain synaptosomes as well as the binding of LqhalphaIT, a scorpion alpha-toxin highly active on insects, to cockroach neuronal membranes. Moreover, delta-atracotoxin-Hv1 cooperatively enhanced batrachotoxin binding to rat brain synaptosomes in an analogous fashion to scorpion alpha-toxins. Thus the delta-atracotoxins represent a new class of toxins which bind to both mammalian and insect sodium channels at sites similar to, or partially overlapping with, the receptor binding sites of scorpion alpha-toxins.

delta-Atracotoxins from the venom of Australian funnel-web spiders are a unique group of peptide toxins that slow sodium current inactivation in a manner similar to scorpion alpha-toxins. To analyze their interaction with known sodium channel neurotoxin receptor sites, we studied their effect on [3H]batrachotoxin and 125I-Lqh II (where Lqh is alpha-toxin II from the venom of the scorpion Leiurus quinquestriatus hebraeus) binding and on alkaloid toxin-stimulated 22Na+ uptake in rat brain synaptosomes. delta-Atracotoxins significantly increased [3H]batrachotoxin binding yet decreased maximal batrachotoxin-activated 22Na+ uptake by 70-80%, the latter in marked contrast to the effect of scorpion alpha-toxins. Unlike the inhibition of batrachotoxin-activated 22Na+ uptake, delta-atracotoxins increased veratridine-stimulated 22Na+ uptake by converting veratridine from a partial to a full agonist, analogous to scorpion alpha-toxins. Hence, delta-atracotoxins are able to differentiate between the open state of the sodium channel stabilized by batrachotoxin and veratridine and suggest a distinct sub-conductance state stabilized by delta-atracotoxins. Despite these actions, low concentrations of delta-atracotoxins completely inhibited the binding of the scorpion alpha-toxin, 125I-Lqh II, indicating that they bind to similar, or partially overlapping, receptor sites. The apparent uncoupling between the increase in binding but inhibition of the effect of batrachotoxin induced by delta-atracotoxins suggests that the binding and action of certain alkaloid toxins may represent at least two distinguishable steps. These results further contribute to the understanding of the complex dynamic interactions between neurotoxin receptor site areas related to sodium channel gating.

The present study investigates the actions of robustoxin (atracotoxin-Ar1) purified from the venom of the male Sydney funnel-web spider Atrax robustus on sodium channel gating. Using whole-cell patch-clamp techniques the study assessed the actions of robustoxin on tetrodotoxin-resistant (TTX-R) and tetrodotoxin-sensitive (TTX-S) sodium currents in rat dorsal root ganglion cells. Similar to the closely related funnel-web spider toxin versutoxin (delta-atracotoxin-Hv1) from Hadronyche versuta, robustoxin had no effect on TTX-R sodium currents but exerted potent effects on TTX-S sodium currents. The main action of robustoxin was a concentration-dependent slowing or removal of TTX-S sodium current inactivation. This steady-state current was maintained during long-lasting depolarisations at all test potentials. Robustoxin (30 nM) also caused a 13-mV hyperpolarising shift in the voltage midpoint of steady-state sodium channel inactivation (h infinity) leading to a reduced peak current at a holding potential of -80 mV. Moreover there was a steady-state or non-inactivating component present (18% of maximal sodium current) at prepulse potentials that normally inactivate all TTX-S sodium channels (more depolarised than -40 mV). In addition robustoxin produced a significant increase in the repriming kinetics of the sodium channel when channels returned to the resting state following activation. This increase in the rate of recovery of sodium current appears to explain the use-dependent effects on peak sodium current amplitude at high stimulation frequencies. Finally 30 nM robustoxin caused an 11-mV hyperpolarising shift in the voltage dependence of the channel but did not markedly modify tail current kinetics. These actions suggest that robustoxin inhibits conversion of the open state to the inactivated state of TTX-S sodium channels, thus allowing a fraction of the sodium current to remain at membrane potentials at which inactivation is normally complete. Given the recent reclassification of funnel-web spider toxins as atracotoxins, robustoxin should henceforth be known as delta-atracotoxin-Ar1 to reflect this main action on sodium channel inactivation. These present results further support the hypothesis that funnel-web spider toxins interact with neurotoxin receptor site 3 to slow channel inactivation in a manner similar to that of alpha-scorpion and sea anemone toxins.

We describe the extraction and enrichment of membrane proteins for separation by two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) after differential solubilization of an Escherichia coli cell lysate. In a simple three-step sequential solubilization protocol applicable for whole cell lysates, membrane proteins are partitioned from other cellular proteins by their insolubility in solutions conventionally used for isoelectric focusing (IEF). As the first step, Tris-base was used to solubilize many cytosolic proteins. The resultant pellet was then subjected to conventional solubilizing solutions (urea, 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate, dithiothreitol, Tris, carrier ampholytes). Following the completion of this step, 89% of the initial E. coli sample mass was solubilized. Finally, the membrane protein rich pellet was partially solubilized using a combination of urea, thiourea, tributyl phosphine and multiple zwitterionic surfactants. Using N-terminal sequence tagging and peptide mass fingerprinting we have identified 11 membrane proteins from this pellet. Two of these outer membrane proteins (Omp), OmpW and OmpX, have previously been known only as an open reading frame in E. coli, while OmpC, OmpT and OmpTOLC have not previously been identified on a 2-D gel. The prefractionation of an entire cell lysate into multiple fractions, based on solubility, results in simplified protein patterns following 2-D PAGE using broad-range pH 3.5-10 immobilized pH gradients (IPGs). Additional advantages of sample prefractionation are that protein identification and gel matching, for database construction, is a more manageable task, the procedure requires no specialized apparatus, and the sequential extraction is conducted in a single centrifuge tube, minimizing protein loss.

To understand the changes in protein expression associated with various physiological states as well as the development of pathological eye disease, we have begun to map the protein components of normal human reflex tears. An analytical reference map of normal human reflex tears was created using two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) with pH 3.5-10 immobilized pH gradients (IPGs). Micropreparatively loaded gels were transferred to polyvinylidene difluoride (PVDF) and analysed by a combination of N-terminal sequence tagging and amino acid compositional analysis. Thirty spots were sequence tagged, resulting in identification of six different proteins (lipocalin, lysozyme, lactotransferrin, zinc-alpha-2 glycoprotein, cystatin S, cystatin SN) that matched to entries in the SWISS-PROT database. A group of N-terminally blocked proteins was clearly identified from SWISS-PROT by amino acid analysis, isoelectric point (pI) and molecular weight (Mr). A number of highly expressed protein components remain unidentified despite being subjected to amino acid analysis and Edman sequencing. A majority of the abundant proteins showed varying degrees of charge heterogeneity attributed to post-translational processing such as glycosylation and N-terminal truncation. We have identified a previously undescribed protein that we have named lacryglobin. This protein displays strong homology with mammaglobin, a protein overexpressed in breast cancer. The discovery of this homologue in tears offers the potential for disease diagnosis by screening tear fluid proteins.

The amino acid sequence of a previously undescribed toxin from Australian death adder venom (Acanthophis antarcticus) has been elucidated. It appears to exist in two forms which are separated by reverse-phase high-performance liquid chromatography, but which have the same sequence and mol. wt. It has 79 amino acid residues and is therefore longer than other long postsynaptic neurotoxins. It shows homology with the conserved regions of the other long postsynaptic neurotoxins except for three unique substitutions of conserved residues, which are Arg-29 instead of Trp or Phe, Leu-33 instead of Arg and Thr-43 instead of Ala.

The present study investigated the action of textilotoxin, isolated from the venom of the Australian common brown snake Pseudonaja textilis, on neuromuscular transmission in isolated toad nerve-muscle preparations. Initial muscle twitch tension experiments revealed a triphasic pattern of changes in muscle tension and a irreversible binding action of textilotoxin (10 micrograms/ml) similar to other snake beta-neurotoxins. This was characterised by an initial depression of twitch tension, followed by a period of enhanced tension, eventually leading to a reduction in tension to complete neuromuscular blockade. These actions on muscle tension were investigated further by assessing the action of textilotoxin on end-plate potential amplitude (EPP). This revealed a similar triphasic alteration of the nerve-evoked release of acetylcholine from the motor nerve terminal. These actions on acetylcholine release were confirmed to be of a presynaptic origin since the modal amplitude of miniature end-plate potentials (MEPPs) was not reduced and in twitch tension experiments the muscle still contracted in response to direct muscle stimulation when nerve-evoked release was completely blocked. Interestingly dramatic effects were observed on the spontaneous release of acetylcholine, including an marked increase in MEPP frequency, a skewing of the MEPP amplitude frequency histogram to the right, and a resultant increase in the number of 'giant' MEPPs. These results indicate that textilotoxin causes a presynaptic blockade of neuromuscular transmission involving a disruption of the regulatory mechanism that controls acetylcholine release.

Robustoxin is the lethal polypeptide toxin in Atrax robustus venom. A monoclonal antibody was produced using synthetic, unfolded robustoxin conjugated to keyhole limpet haemocyanin as the immunogen. This monoclonal antibody did not protect newborn mice against challenge with the crude venom of the male Sydney funnel-web spider, but did slightly prolong their survival time. Western blotted crude venom of the male Sydney funnel-web spider showed two monoclonal antibody binding bands. One band at low M(r) corresponded to robustoxin (M(r) 4854), while the other higher M(r) band (approximately 37,000) may be due to a pre-robustoxin molecule.

The complete amino-acid sequences of subunits A, B, C and D of textilotoxin, the presynaptic neurotoxin from the venom of the Australian common brown snake, Pseudonaja textilis, were determined. These confirmed that it is structurally the most complex of any of the known snake venom neurotoxins. Textilotoxin consists of 623 amino-acid residues in five subunits (subunit A, 118 residues; subunit B, 121 residues; subunit C, 118 residues; subunit D, two chains of 133 residues each). All subunits A, B, C and D contain the putative phospholipase A2 active site. Only subunit A showed any lethality on its own (4 mg/kg i.v. in mice). Subunit D contained two identical covalently-linked subunits and was weakly glycosylated. All subunits were necessary for maximum lethality at 1 micrograms/kg mice intraperitoneally. Details of the sequences of the subunits A, B and C are reported and interesting homology with other snake venom phospholipase A2 neurotoxins indicated.

One of the main problems still hampering solid-phase peptide synthesis using orthogonal protection strategies based on the 9-fluorenylmethoxycarbonyl amino protecting group is the difficult removal of currently used arginine arylsulphonyl guanidino protecting groups. Poor acid liability of 4-methoxy-2,3,6-trimethylbenzenesulphonyl-protected arginine has led to the popularity of the newer 2,2,5,7,8- pentamethylchroman-6-sulphonyl guanidino protecting group. This group was initially believed to have liability to trifluoroacetic acid, the reagent commonly used to simultaneously deprotect peptides and detach them from the synthesis resin, comparable to tert.-butyl and trityl type protecting groups used for the protection of other peptide side-chain functionalities. In a comparison of three established cleavage/deprotection mixtures we have shown that this is not always the case, particularly in multiple arginine peptides. We have found that only hard-acid deprotection with trimethylsilyl bromide reliably removed both arylsulphonyl guanidino protecting groups from a variety of arginine-containing peptides.

A peptide containing four threonine residues was synthesised by the solid-phase method using fluorenyl-methoxycarbonylamino acid reactive esters or coupling by preactivation with 1-hydroxybenzotriazole and Castro's reagent. In two separate experiments the synthesis was carried out with or without protection of the side-chain hydroxyl group of threonine as the tert.-butyl ether. Comparison of the crude peptides after deprotection and detachment from the synthesis resin suggests that side-chain protection of threonine is unnecessary under the synthetic conditions employed.

Textilotoxin is a presynaptic neurotoxin in the venom of the Australian common brown snake, Pseudonaja textilis. It has the highest lethality and is structurally the most complex of any known snake venom neurotoxin. Reverse-phase HPLC was used to resolve textilotoxin into subunits A, B, C and D. Subunit D consists of two identical covalently linked polypeptide chains. Its sequence is now reported. It is an acidic, slightly glycosylated polypeptide of 133 amino acid residues in each chain. Although it is not itself neurotoxic, it was found to be essential for the neurotoxicity of textilotoxin.

The binding of textilotoxin and its subunits A, B, C and D to polyclonal rabbit antisera directed against textilotoxin, Australian common brown snake (Pseudonaja textilis) and tiger snake (Notechis scutatus scutatus) venoms was studied by ELISA. Subunit D showed greatest reactivity with antisera to textilotoxin and brown snake venom. The phospholipase A2 active subunit A reacted more strongly with antisera to tiger snake venom in keeping with the high degree of homology between the amino acid sequences of subunit A and notexin from tiger snake venom. Subunit A was the only subunit lethal to mice, but at doses 1000-fold greater than for textilotoxin.

The effect of stimulation frequency on the timecourse of neuromuscular blockade, following the administration of textilotoxin (20 micrograms/kg) or beta-bungarotoxin (50 micrograms/kg), was examined in the interdigital muscles of the hindlimb in anaesthetized mice. While the time of death was variable, neuromuscular blockade of the interdigital muscles occurred at the same time as respiratory failure with both textilotoxin and beta-bungarotoxin only at stimulation rates of 0.5 Hz and above. Textilotoxin (50 micrograms/kg) produced an increase in the heart rate prior to death but no change in the shape of the electrocardiogram.

1. A lethal neurotoxin (acanthophin d) was isolated from the venom of the Australian death adder snake Acanthophis antarcticus. 2. Acanthophin d consisted of a single polypeptide chain of 74 amino acid residues cross-linked by five disulphide bridges. 3. The results of neurophysiological experiments on murine phrenic nerve hemi-diaphragm preparations were consistent with irreversible post-synaptic blockage of neuromuscular transmission by acanthophin d.

Five biologically active daphnane orthoesters have been isolated from Pimelea species (Thymelaeaceae). Four of these possessing antineoplastic activity against in vivo murine P-388 lymphocytic leukemia are gnidimacrin from P. ligustrina, simpleximacrin from P. simplex, linimacrin d and Pimelea factor P3 from P. linifolia. Linimacrin c from P. linifolia and the other four compounds showed piscicidal activity. Gnidimacrin and Pimelea factor P3 have previously been isolated from other members of the Thymelaeaceae. Simpleximacrin and linimacrins c and d are new compounds.

Textilotoxin is a presynaptic neurotoxin from the venom of the Australian common brown snake, Pseudonaja textilis. It has the highest lethality and is structurally the most complex of any known snake venom neurotoxin. It was resolved into its five non-covalently linked subunits in a single step by reverse-phase HPLC. Two of the subunits were identical. The N-terminal amino-acid sequence and amino-acid composition of each subunit were determined. Subunit A was the only one found to possess phospholipase A activity. Separation of textilotoxin into its subunits was reversible and reformed textilotoxin had the same Mr and lethality in mice as the native toxin. Experiments with various unnatural combinations of subunits have led to interesting variations in lethality and Mr of the resulting complexes.

The complete amino acid sequence of pseudonajatoxin b, a basic neurotoxin from the venom of the Australian common brown snake, Pseudonaja textilis, was determined by automated Edman analysis of the reduced carboxymethylated polypeptide and of peptides derived by digestion of it with Staphylococcus aureus V8 proteinase. Pseudonajatoxin b consists of a single polypeptide chain of 71 amino acids with Mr 7762. The amino acid sequence showed considerable homology with postsynaptic long neurotoxins, but there were striking differences. Pseudonajatoxin b displayed relatively high lethality, LD50 15 micrograms/kg in mice.

The complete amino acid sequence of versutoxin, a lethal neurotoxic polypeptide isolated from the venom of male and female funnel-web spiders of the species Atrax versutus, was determined. Sequencing was performed in a gas-phase protein sequencer by automated Edman degradation of the S-carboxymethylated toxin and fragments of it produced by reaction with CNBr. Versutoxin consisted of a single chain of 42 amino acid residues. It was found to have a high proportion of basic residues and of cystine. The primary structure showed marked homology with that of robustoxin, a novel neurotoxin recently isolated from the venom of another funnel-web-spider species, Atrax robustus.

A growth hormone-dependent binding protein for insulin-like growth factors (IGF-I and IGF-II) has been isolated from human plasma. Analyzed on SDS gels, the preparation contained a major protein band of 53 kDa, and a minor band of 47 kDa. After transfer to nitrocellulose, both species bound iodinated IGF-I, and could be detected using an antibody raised against the purified preparation. In contrast, an IGF binding protein purified from human amniotic fluid bound IGF-I but was not detectable immunologically. The amino acid comparison of the plasma binding protein preparation was different from that reported for amniotic fluid and HEP G2 hepatoma proteins, and the unique amino-terminal sequence, Gly-Ala-Ser-Ser-Ala-Gly-Leu-Gly-Pro-Val-, was different from that of the amniotic fluid and hepatoma proteins. This study indicates that the growth hormone-dependent IGF binding protein of human plasma is structurally and immunologically distinct from other IGF binding proteins.