Core-shell model of the clusters of CPEB4 isoforms preceding liquid-liquid phase separation.

Protein solutions can undergo liquid-liquid phase separation (LLPS), where a dispersed phase with a low protein concentration coexists with coacervates with a high protein concentration. We focus on the low complexity N-terminal domain of cytoplasmic polyadenylation element binding-4 protein, CPEB4NTD, and its isoform depleted of the Exon4, CPEB4Δ4NTD. They both exhibit LLPS, but in contrast to most systems undergoing LLPS, the single-phase regime preceding LLPS consists mainly of soluble protein clusters. We combine experimental and theoretical approaches to resolve the internal structure of the clusters and the basis for their formation. Dynamic light scattering and atomic force microscopy show that both isoforms exhibit clusters with diameters ranging from 35 to 80 nm. Electron paramagnetic resonance spectroscopy of spin-labeled CPEB4NTD and CPEB4Δ4NTD revealed that these proteins have two distinct dynamical properties in both the clusters and coacervates. Based on the experimental results, we propose a core-shell structure for the clusters, which is supported by the agreement of the dynamic light scattering data on cluster size distribution with a statistical model developed to describe the structure of clusters. This model treats clusters as swollen micelles (microemulsions) where the core and the shell regions comprise different protein conformations, in agreement with the electron paramagnetic resonance detection of two protein populations. The effects of ionic strength and the addition of 1,6-hexanediol were used to probe the interactions responsible for cluster formation. While both CPEB4NTD and CPEB4Δ4NTD showed phase separation with increasing temperature and formed clusters, differences were found in the properties of the clusters and the coacervates. The data also suggested that the coacervates may consist of aggregates of clusters.

Magnetic Monopole-Like Behavior in Superparamagnetic Nanoparticle Coated With Chiral Molecules.

Superparamagnetic iron oxide nanoparticles (SPIONs) have attracted wide attention due to their promising applications in biomedicine, chemical catalysis, and magnetic memory devices. In this work, the force is measured between a single SPION coated with chiral molecules and a ferromagnetic substrate by atomic force microscopy (AFM), with the substrate magnetized either toward or away from the approaching AFM tip. The force between the coated SPION and the magnetic substrate depends on the handedness of the molecules adsorbed on the SPION and on the direction of the magnetization of the substrate. By inserting nm-scale spacing layers between the coated SPION and the magnetic substrate it is shown that the SPION has a short-range magnetic monopole-like magnetic field. A theoretical framework for the nature of this field is provided.

Malaria parasites release vesicle subpopulations with signatures of different destinations.

Malaria is the most serious mosquito-borne parasitic disease, caused mainly by the intracellular parasite Plasmodium falciparum. The parasite invades human red blood cells and releases extracellular vesicles (EVs) to alter its host responses. It becomes clear that EVs are generally composed of sub-populations. Seeking to identify EV subpopulations, we subject malaria-derived EVs to size-separation analysis, using asymmetric flow field-flow fractionation. Multi-technique analysis reveals surprising characteristics: we identify two distinct EV subpopulations differing in size and protein content. Small EVs are enriched in complement-system proteins and large EVs in proteasome subunits. We then measure the membrane fusion abilities of each subpopulation with three types of host cellular membranes: plasma, late and early endosome. Remarkably, small EVs fuse to early endosome liposomes at significantly greater levels than large EVs. Atomic force microscope imaging combined with machine-learning methods further emphasizes the difference in biophysical properties between the two subpopulations. These results shed light on the sophisticated mechanism by which malaria parasites utilize EV subpopulations as a communication tool to target different cellular destinations or host systems.

C-Axis Textured, 2-3 µm Thick Al0.75Sc0.25N Films Grown on Chemically Formed TiN/Ti Seeding Layers for MEMS Applications.

A protocol for successfully depositing [001] textured, 2−3 µm thick films of Al0.75Sc0.25N, is proposed. The procedure relies on the fact that sputtered Ti is [001]-textured α-phase (hcp). Diffusion of nitrogen ions into the α-Ti film during reactive sputtering of Al0.75,Sc0.25N likely forms a [111]-oriented TiN intermediate layer. The lattice mismatch of this very thin film with Al0.75Sc0.25N is ~3.7%, providing excellent conditions for epitaxial growth. In contrast to earlier reports, the Al0.75Sc0.25N films prepared in the current study are Al-terminated. Low growth stress (<100 MPa) allows films up to 3 µm thick to be deposited without loss of orientation or decrease in piezoelectric coefficient. An advantage of the proposed technique is that it is compatible with a variety of substrates commonly used for actuators or MEMS, as demonstrated here for both Si wafers and D263 borosilicate glass. Additionally, thicker films can potentially lead to increased piezoelectric stress/strain by supporting application of higher voltage, but without increase in the magnitude of the electric field.

Efficacy of catheter-based renal denervation in the absence of antihypertensive medications (SPYRAL HTN-OFF MED Pivotal): a multicentre, randomised, sham-controlled trial.

BACKGROUND: Catheter-based renal denervation has significantly reduced blood pressure in previous studies. Following a positive pilot trial, the SPYRAL HTN-OFF MED (SPYRAL Pivotal) trial was designed to assess the efficacy of renal denervation in the absence of antihypertensive medications. METHODS: In this international, prospective, single-blinded, sham-controlled trial, done at 44 study sites in Australia, Austria, Canada, Germany, Greece, Ireland, Japan, the UK, and the USA, hypertensive patients with office systolic blood pressure of 150 mm Hg to less than 180 mm Hg were randomly assigned 1:1 to either a renal denervation or sham procedure. The primary efficacy endpoint was baseline-adjusted change in 24-h systolic blood pressure and the secondary efficacy endpoint was baseline-adjusted change in office systolic blood pressure from baseline to 3 months after the procedure. We used a Bayesian design with an informative prior, so the primary analysis combines evidence from the pilot and Pivotal trials. The primary efficacy and safety analyses were done in the intention-to-treat population. This trial is registered at ClinicalTrials.gov, NCT02439749. FINDINGS: From June 25, 2015, to Oct 15, 2019, 331 patients were randomly assigned to either renal denervation (n=166) or a sham procedure (n=165). The primary and secondary efficacy endpoints were met, with posterior probability of superiority more than 0·999 for both. The treatment difference between the two groups for 24-h systolic blood pressure was -3·9 mm Hg (Bayesian 95% credible interval -6·2 to -1·6) and for office systolic blood pressure the difference was -6·5 mm Hg (-9·6 to -3·5). No major device-related or procedural-related safety events occurred up to 3 months. INTERPRETATION: SPYRAL Pivotal showed the superiority of catheter-based renal denervation compared with a sham procedure to safely lower blood pressure in the absence of antihypertensive medications. FUNDING: Medtronic.

Unusual Surface Texture, Dimensions and Morphology Variations of Chiral and Single Crystals*.

We demonstrate here a unique metallo-organic material where the appearance and the internal crystal structure are in contradiction. The egg-shaped (ovoid) crystals have a brain-like texture. Although these micro-sized crystals are monodispersed; like fingerprints their grainy surfaces are never exactly alike. Remarkably, our X-ray and electron diffraction studies unexpectedly revealed that these structures are single-crystals comprising a continuous coordination network of two differently shaped homochiral channels. By using the same building blocks under different reaction conditions, a rare series of crystals have been obtained that are uniquely rounded in their shape. In stark contrast to the brain-like crystals, these isostructural and monodispersed crystals have a comparatively smooth appearance. The sizes of these crystals vary by several orders of magnitude.

Control over size, shape, and photonics of self-assembled organic nanocrystals.

The facile fabrication of free-floating organic nanocrystals (ONCs) was achieved via the kinetically controlled self-assembly of simple perylene diimide building blocks in aqueous medium. The ONCs have a thin rectangular shape, with an aspect ratio that is controlled by the content of the organic cosolvent (THF). The nanocrystals were characterized in solution by cryogenic transmission electron microscopy (cryo-TEM) and small-angle X-ray scattering. The ONCs retain their structure upon drying, as was evidenced by TEM and atom force microscopy. Photophysical studies, including femtosecond transient absorption spectroscopy, revealed a distinct influence of the ONC morphology on their photonic properties (excitation energy transfer was observed only in the high-aspect ONCs). Convenient control over the structure and function of organic nanocrystals can enhance their utility in new and developed technologies.

Chiral and SHG-Active Metal-Organic Frameworks Formed in Solution and on Surfaces: Uniformity, Morphology Control, Oriented Growth, and Postassembly Functionalization.

We demonstrate the formation of uniform and oriented metal-organic frameworks using a combination of anion effects and surface chemistry. Subtle but significant morphological changes result from the nature of the coordinative counteranion of the following metal salts: NiX2 with X = Br-, Cl-, NO3-, and OAc-. Crystals could be obtained in solution or by template surface growth. The latter results in truncated crystals that resemble a half structure of the solution-grown ones. The oriented surface-bound metal-organic frameworks (sMOFs) are obtained via a one-step solvothermal approach rather than in a layer-by-layer approach. The MOFs are grown on Si/SiOx substrates modified with an organic monolayer or on glass substrates covered with a transparent conductive oxide (TCO). Regardless of the different morphologies, the crystallographic packing is nearly identical and is not affected by the type of anion or by solution versus the surface chemistry. A propeller-type arrangement of the nonchiral ligands around the metal center affords a chiral structure with two geometrically different helical channels in a 2:1 ratio with the same handedness. To demonstrate the accessibility and porosity of the macroscopically oriented channels, a chromophore (resorufin sodium salt) was successfully embedded into the channels of the crystals by diffusion from solution, resulting in fluorescent crystals. These "colored" crystals displayed polarized emission (red) with a high polarization ratio because of the alignment of these dyes imposed by the crystallographic structure. A second-harmonic generation (SHG) study revealed Kleinman symmetry-forbidden nonlinear optical properties. These surface-bound and oriented SHG-active MOFs have the potential for use as single nonlinear optical (NLO) devices.

Histamine releasing factor and elongation factor 1 alpha secreted via malaria parasites extracellular vesicles promote immune evasion by inhibiting specific T cell responses.

Protozoan pathogens secrete nanosized particles called extracellular vesicles (EVs) to facilitate their survival and chronic infection. Here, we show the inhibition by Plasmodium berghei NK65 blood stage-derived EVs of the proliferative response of CD4+ T cells in response to antigen presentation. Importantly, these results were confirmed in vivo by the capacity of EVs to diminish the ovalbumin-specific delayed type hypersensitivity response. We identified two proteins associated with EVs, the histamine releasing factor (HRF) and the elongation factor 1α (EF-1α) that were found to have immunosuppressive activities. Interestingly, in contrast to WT parasites, EVs from genetically HRF- and EF-1α-deficient parasites failed to inhibit T cell responses in vitro and in vivo. At the level of T cells, we demonstrated that EVs from WT parasites dephosphorylate key molecules (PLCγ1, Akt, and ERK) of the T cell receptor signalling cascade. Remarkably, immunisation with EF-1α alone or in combination with HRF conferred a long-lasting antiparasite protection and immune memory. In conclusion, we identified a new mechanism by which P. berghei-derived EVs exert their immunosuppressive functions by altering T cell responses. The identification of two highly conserved immune suppressive factors offers new conceptual strategies to overcome EV-mediated immune suppression in malaria-infected individuals.

Laboratory Insights into the Diel Cycle of Optical and Chemical Transformations of Biomass Burning Brown Carbon Aerosols.

Transformations of biomass burning brown carbon aerosols (BB-BrC) over their diurnal lifecycle are currently not well studied. In this study, the aging of BB tar proxy aerosols processed by NO3• under dark conditions followed by the photochemical OH• reaction and photolysis were investigated in tandem flow reactors. The results show that O3 oxidation in the dark diminishes light absorption of wood tar aerosols, resulting in higher particle single-scattering albedo (SSA). NO3• reactions augment the mass absorption coefficient (MAC) of the aerosols by a factor of 2-3 by forming secondary chromophores, such as nitroaromatic compounds (NACs) and organonitrates. Subsequent OH• oxidation and direct photolysis both decompose the organic nitrates (ONs, representing bulk functionalities of NACs and organonitrates) in the NO3•-aged wood tar aerosols, thus decreasing particle absorption. Moreover, NACs degrade faster than organonitrates by photochemical aging. The NO3•-aged wood tar aerosols are more susceptible to photolysis than to OH• reactions. The photolysis lifetimes for the ONs and for the absorbance of the NO3•-aged aerosols are on the order of hours under typical solar irradiation, while the absorption and ON lifetimes toward OH• oxidation are substantially longer. Overall, nighttime aging via NO3• reactions increases the light absorption of wood tar aerosols and shortens their absorption lifetime under daytime conditions.

Effect of renal denervation on blood pressure in the presence of antihypertensive drugs: 6-month efficacy and safety results from the SPYRAL HTN-ON MED proof-of-concept randomised trial.

BACKGROUND: Previous catheter-based renal denervation studies have reported variable efficacy results. We aimed to evaluate safety and blood pressure response after renal denervation or sham control in patients with uncontrolled hypertension on antihypertensive medications with drug adherence testing. METHODS: In this international, randomised, single-blind, sham-control, proof-of-concept trial, patients with uncontrolled hypertension (aged 20-80 years) were enrolled at 25 centres in the USA, Germany, Japan, UK, Australia, Austria, and Greece. Eligible patients had an office systolic blood pressure of between 150 mm Hg and 180 mm Hg and a diastolic blood pressure of 90 mm Hg or higher; a 24 h ambulatory systolic blood pressure of between 140 mm Hg and 170 mm Hg at second screening; and were on one to three antihypertensive drugs with stable doses for at least 6 weeks. Patients underwent renal angiography and were randomly assigned to undergo renal denervation or sham control. Patients, caregivers, and those assessing blood pressure were masked to randomisation assignments. The primary efficacy endpoint was blood pressure change from baseline (measured at screening visit two), based on ambulatory blood pressure measurements assessed at 6 months, as compared between treatment groups. Drug surveillance was used to assess medication adherence. The primary analysis was done in the intention-to-treat population. Safety events were assessed through 6 months as per major adverse events. This trial is registered with ClinicalTrials.gov, number NCT02439775, and follow-up is ongoing. FINDINGS: Between July 22, 2015, and June 14, 2017, 467 patients were screened and enrolled. This analysis presents results for the first 80 patients randomly assigned to renal denervation (n=38) and sham control (n=42). Office and 24 h ambulatory blood pressure decreased significantly from baseline to 6 months in the renal denervation group (mean baseline-adjusted treatment differences in 24 h systolic blood pressure -7·0 mm Hg, 95% CI -12·0 to -2·1; p=0·0059, 24 h diastolic blood pressure -4·3 mm Hg, -7·8 to -0·8; p=0.0174, office systolic blood pressure -6·6 mm Hg, -12·4 to -0·9; p=0·0250, and office diastolic blood pressure -4·2 mm Hg, -7·7 to -0·7; p=0·0190). The change in blood pressure was significantly greater at 6 months in the renal denervation group than the sham-control group for office systolic blood pressure (difference -6·8 mm Hg, 95% CI -12·5 to -1·1; p=0·0205), 24 h systolic blood pressure (difference -7·4 mm Hg, -12·5 to -2·3; p=0·0051), office diastolic blood pressure (difference -3·5 mm Hg, -7·0 to -0·0; p=0·0478), and 24 h diastolic blood pressure (difference -4·1 mm Hg, -7·8 to -0·4; p=0·0292). Evaluation of hourly changes in 24 h systolic blood pressure and diastolic blood pressure showed blood pressure reduction throughout 24 h for the renal denervation group. 3 month blood pressure reductions were not significantly different between groups. Medication adherence was about 60% and varied for individual patients throughout the study. No major adverse events were recorded in either group. INTERPRETATION: Renal denervation in the main renal arteries and branches significantly reduced blood pressure compared with sham control with no major safety events. Incomplete medication adherence was common. FUNDING: Medtronic.

Diameter-dependent wetting of tungsten disulfide nanotubes.

The simple process of a liquid wetting a solid surface is controlled by a plethora of factors-surface texture, liquid droplet size and shape, energetics of both liquid and solid surfaces, as well as their interface. Studying these events at the nanoscale provides insights into the molecular basis of wetting. Nanotube wetting studies are particularly challenging due to their unique shape and small size. Nonetheless, the success of nanotubes, particularly inorganic ones, as fillers in composite materials makes it essential to understand how common liquids wet them. Here, we present a comprehensive wetting study of individual tungsten disulfide nanotubes by water. We reveal the nature of interaction at the inert outer wall and show that remarkably high wetting forces are attained on small, open-ended nanotubes due to capillary aspiration into the hollow core. This study provides a theoretical and experimental paradigm for this intricate problem.

Catheter-based renal denervation in patients with uncontrolled hypertension in the absence of antihypertensive medications (SPYRAL HTN-OFF MED): a randomised, sham-controlled, proof-of-concept trial.

BACKGROUND: Previous randomised renal denervation studies did not show consistent efficacy in reducing blood pressure. The objective of our study was to evaluate the effect of renal denervation on blood pressure in the absence of antihypertensive medications. METHODS: SPYRAL HTN-OFF MED was a multicentre, international, single-blind, randomised, sham-controlled, proof-of-concept trial. Patients were enrolled at 21 centres in the USA, Europe, Japan, and Australia. Eligible patients were drug-naive or discontinued their antihypertensive medications. Patients with an office systolic blood pressure (SBP) of 150 mm Hg or greater and less than 180 mm Hg, office diastolic blood pressure (DBP) of 90 mm Hg or greater, and a mean 24-h ambulatory SBP of 140 mm Hg or greater and less than 170 mm Hg at second screening underwent renal angiography and were randomly assigned to renal denervation or sham control. Patients, caregivers, and those assessing blood pressure were blinded to randomisation assignments. The primary endpoint, change in 24-h blood pressure at 3 months, was compared between groups. Drug surveillance was done to ensure patient compliance with absence of antihypertensive medication. The primary analysis was done in the intention-to-treat population. Safety events were assessed at 3 months. This study is registered with ClinicalTrials.gov, number NCT02439749. FINDINGS: Between June 25, 2015, and Jan 30, 2017, 353 patients were screened. 80 patients were randomly assigned to renal denervation (n=38) or sham control (n=42) and followed up for 3 months. Office and 24-h ambulatory blood pressure decreased significantly from baseline to 3 months in the renal denervation group: 24-h SBP -5·5 mm Hg (95% CI -9·1 to -2·0; p=0·0031), 24-h DBP -4·8 mm Hg (-7·0 to -2·6; p<0·0001), office SBP -10·0 mm Hg (-15·1 to -4·9; p=0·0004), and office DBP -5·3 mm Hg (-7·8 to -2·7; p=0·0002). No significant changes were seen in the sham-control group: 24-h SBP -0·5 mm Hg (95% CI -3·9 to 2·9; p=0·7644), 24-h DBP -0·4 mm Hg (-2·2 to 1·4; p=0·6448), office SBP -2·3 mm Hg (-6·1 to 1·6; p=0·2381), and office DBP -0·3 mm Hg (-2·9 to 2·2; p=0·8052). The mean difference between the groups favoured renal denervation for 3-month change in both office and 24-h blood pressure from baseline: 24-h SBP -5·0 mm Hg (95% CI -9·9 to -0·2; p=0·0414), 24-h DBP -4·4 mm Hg (-7·2 to -1·6; p=0·0024), office SBP -7·7 mm Hg (-14·0 to -1·5; p=0·0155), and office DBP -4·9 mm Hg (-8·5 to -1·4; p=0·0077). Baseline-adjusted analyses showed similar findings. There were no major adverse events in either group. INTERPRETATION: Results from SPYRAL HTN-OFF MED provide biological proof of principle for the blood-pressure-lowering efficacy of renal denervation. FUNDING: Medtronic.

Tubular Hybrids: A Nanoparticle-Molecular Network.

We report here a new methodology for the formation of freestanding nanotubes composed of individual gold nanoparticles (NPs) cross-linked by coordination complexes or porphyrin molecules using WS2 nanotubes (INT-WS2) as a template. Our method consists of three steps: (i) coverage of these robust inorganic materials with monodispersed and dense monolayers of gold NPs, (ii) formation of a molecular AuNP network by exposing these decorated tubes to solutions containing a ruthenium polypyridyl complex or meso-tetra(4-pyridyl)porphyrin, and (iii) removal of the INT-WS2 template with a hydrogen peroxide solution. Nanoindentation of the template-free AuNP tubes with atomic force microscopy indicates a radial elastic modulus of 4 GPa. The template-free molecular AuNP tubes are characterized using scanning and transmission electron microscopy, energy-dispersive X-ray spectroscopy, and micro-Raman spectroscopy. The methodology provides a convenient and scalable strategy for the realization of molecular AuNP tubes with a defined length and diameter, depending on the dimensions of the template.

A controlled trial of renal denervation for resistant hypertension.

BACKGROUND: Prior unblinded studies have suggested that catheter-based renal-artery denervation reduces blood pressure in patients with resistant hypertension. METHODS: We designed a prospective, single-blind, randomized, sham-controlled trial. Patients with severe resistant hypertension were randomly assigned in a 2:1 ratio to undergo renal denervation or a sham procedure. Before randomization, patients were receiving a stable antihypertensive regimen involving maximally tolerated doses of at least three drugs, including a diuretic. The primary efficacy end point was the change in office systolic blood pressure at 6 months; a secondary efficacy end point was the change in mean 24-hour ambulatory systolic blood pressure. The primary safety end point was a composite of death, end-stage renal disease, embolic events resulting in end-organ damage, renovascular complications, or hypertensive crisis at 1 month or new renal-artery stenosis of more than 70% at 6 months. RESULTS: A total of 535 patients underwent randomization. The mean (±SD) change in systolic blood pressure at 6 months was -14.13±23.93 mm Hg in the denervation group as compared with -11.74±25.94 mm Hg in the sham-procedure group (P<0.001 for both comparisons of the change from baseline), for a difference of -2.39 mm Hg (95% confidence interval [CI], -6.89 to 2.12; P=0.26 for superiority with a margin of 5 mm Hg). The change in 24-hour ambulatory systolic blood pressure was -6.75±15.11 mm Hg in the denervation group and -4.79±17.25 mm Hg in the sham-procedure group, for a difference of -1.96 mm Hg (95% CI, -4.97 to 1.06; P=0.98 for superiority with a margin of 2 mm Hg). There were no significant differences in safety between the two groups. CONCLUSIONS: This blinded trial did not show a significant reduction of systolic blood pressure in patients with resistant hypertension 6 months after renal-artery denervation as compared with a sham control. (Funded by Medtronic; SYMPLICITY HTN-3 ClinicalTrials.gov number, NCT01418261.).

Sympathetic Response and Outcomes Following Renal Denervation in Patients With Chronic Heart Failure: 12-Month Outcomes From the Symplicity HF Feasibility Study.

BACKGROUND: Heart failure (HF) is associated with chronic sympathetic activation. Renal denervation (RDN) aims to reduce sympathetic activity by ablating the renal sympathetic nerves. We investigated the effect of RDN in patients with chronic HF and concurrent renal dysfunction in a prospective, multicenter, single-arm feasibility study. METHODS AND RESULTS: Thirty-nine patients with chronic systolic HF (left ventricular ejection fraction [LVEF] <40%, New York Heart Association class II-III,) and renal impairment (estimated glomerular filtration rate [eGFR; assessed with the use of the Modification of Diet in Renal Disease equation] < 75 mL • min-1 • 1.73 m-2) on stable medical therapy were enrolled. Mean age was 65 ± 11 years; 62% had ischemic HF. The average number of ablations per patient was 13 ± 3. No protocol-defined safety events were associated with the procedure. One subject experienced a renal artery occlusion that was possibly related to the denervation procedure. Statistically significant reductions in N-terminal pro-B-type natriuretic peptide (NT-proBNP; 1530 ± 1228 vs 1428 ± 1844 ng/mL; P = .006) and 120-minute glucose tolerance test (11.2 ± 5.1 vs 9.9 ± 3.6; P = .026) were seen at 12 months, but there was no significant change in LVEF (28 ± 9% vs 29 ± 11%; P= .536), 6-minute walk test (384 ± 96 vs 391 ± 97 m; P= .584), or eGFR (52.6 ± 15.3 vs 52.3 ± 18.5 mL • min-1 • 1.73 m-2; P= .700). CONCLUSIONS: RDN was associated with reductions in NT-proBNP and 120-minute glucose tolerance test in HF patients 12 months after RDN treatment. There was no deterioration in other indices of cardiac and renal function in this small feasibility study.

Nonclassical Crystal Growth as Explanation for the Riddle of Polarity in Centrosymmetric Glycine Crystals.

The riddle of anomalous polar behavior of the centrosymmetric crystal of α-glycine is resolved by the discovery of a polar, several hundred nanometer thick hydrated layer, created at the {010} faces during crystal growth. This layer was detected by two independent pyroelectric analytical methods: (i) periodic temperature change technique (Chynoweth) at ambient conditions and (ii) contactless X-ray photoelectron spectroscopy under ultrahigh vacuum. The total polarization of the surface layer is extremely large, yielding ≈1 µC·cm-2, and is preserved in ultrahigh vacuum, but disappears upon heating to 100 °C. Molecular dynamics simulations corroborate the formation of polar hydrated layers at the sub-microsecond time scale, however with a thickness of only several nanometers, not several hundred. This inconsistency might be reconciled by invoking a three-step nonclassical crystal growth mechanism comprising (i) docking of clusters from the supersaturated solution onto the evolving crystal, (ii) surface recognition and polar induction, and (iii) annealing and dehydration, followed by site-selective recrystallization.

Role of muscarinic-3 receptor antibody in systemic sclerosis: correlation with disease duration and effects of IVIG.

Gastrointestinal dysmotility in systemic sclerosis (SSc) is associated with autoantibodies against muscarinic-3 receptor (M3-R). We investigated the temporal course of the site of action of these autoantibodies at the myenteric neurons (MN) vs. the smooth muscle (SM) M3-R in relation to disease duration, and determined the role of intravenous immunoglobulin (IVIG) in reversing these changes. Immunoglobulins purified from SSc patients (SScIgG) were used to assess their differential binding to MN and SM (from rat colon) employing immunohistochemistry (IHC). Effect of SScIgG on neural and direct muscle contraction was determined by cholinergic nerve stimulation and bethanechol-induced SM contraction. Effects of IVIG and its antigen-binding fragment F(ab')2 on SScIgG binding were studied by enzyme-linked immunosorbent assay (ELISA) of rat colonic longitudinal SM myenteric plexus (LSMMP) lysate and to second extracellular loop peptide of M3-R (M3-RL2). SScIgG from all patients demonstrated significantly higher binding to MN than to SM. With progression of SSc duration, binding at MN and SM increased in a linear fashion with a correlation coefficient of 0.696 and 0.726, respectively (P < 0.05). SScIgG-mediated attenuation of neural and direct SM contraction also increased with disease duration. ELISA analysis revealed that IVIG and F(ab')2 significantly reduced SScIgG binding to LSMMP lysate and M3-RL2. Dysmotility in SSc occurs sequentially, beginning with SScIgG-induced blockage of cholinergic neurotransmission (neuropathy), which progresses to inhibition of acetylcholine action at the SM cell (myopathy). IVIG reverses this cholinergic dysfunction at the neural and myogenic receptors by anti-idiotypic neutralization of SScIgG.

The SPYRAL HTN Global Clinical Trial Program: Rationale and design for studies of renal denervation in the absence (SPYRAL HTN OFF-MED) and presence (SPYRAL HTN ON-MED) of antihypertensive medications.

Renal sympathetic activation plays a key role in the pathogenesis of hypertension, as demonstrated by high renal norepinephrine spillover into plasma of patients with essential hypertension. Renal denervation has demonstrated a significant reduction in blood pressure in unblinded studies of hypertensive patients. The SYMPLICITY HTN-3 trial, the first prospective, masked, randomized study of renal denervation versus sham control, failed its primary efficacy end point and raised important questions around potentially confounding factors, such as drug changes and adherence, study population, and procedural methods. The SPYRAL HTN Global Clinical Trial Program is designed to address limitations associated with predicate studies and provide insight into the impact of pharmacotherapy on renal denervation efficacy. The 2 initial trials of the program focus on the effect of renal denervation using the Symplicity Spyral multielectrode renal denervation catheter in hypertensive patients in the absence (SPYRAL HTN OFF-MED) and presence (SPYRAL HTN ON-MED) of antihypertensive medications. The SPYRAL HTN ON-MED study requires patients to be treated with a consistent triple therapy antihypertensive regimen, whereas the SPYRAL HTN OFF-MED study includes a 3- to 4-week drug washout period followed by a 3-month efficacy and safety end point in the absence of antihypertensive medications. The studies will randomize patients with combined systolic-diastolic hypertension to renal denervation or sham procedure. Both studies allow renal denervation treatments in renal artery branches and accessories. These studies will inform the design of the second pivotal phase of the program, which will more definitively analyze the antihypertensive effect of renal denervation.

Metal-organic microstructures: from rectangular to stellated and interpenetrating polyhedra.

Despite the tremendous progress made in the design of supramolecular and inorganic materials, it still remains a great challenge to obtain uniform structures with tailored size and shape. Metal-organic frameworks and infinite coordination polymers are examples of rapidly emerging materials with useful properties, yet limited morphological control. In this paper, we report the solvothermal synthesis of diverse metal-organic (sub)-microstructures with a high degree of uniformity. The porous and thermally robust monodisperse crystalline solids consist of tetrahedral polypyridyl ligands and nickel or copper ions. Our bottom-up approach demonstrates the direct assembly of these materials without the addition of any surfactants or modulators. Reaction parameters in combination with molecular structure encoding are the keys to size-shape control and structural uniformity of our metal-organic materials.