Infusion of Phospholipid Vesicles Amplifies the Local Thrombotic Response to TNF and Anti-Protein C into a Consumptive Response

Inflammation often is considered a contributing factor to both thrombosis and disseminated intravascular coagulation. The molecular mechanisms that dictate which of these clinical manifestations will result from the inflammatory stimulus remain obscure. Bacterial infection and certain tumors are common initiators of the disseminated intravascular coagulant response. Complement activation resulting from bacterial infection shares with selected tumors the capacity to generate or release membrane particles that lack functional adhesion receptors and hence could circulate to amplify a disseminated intravascular coagulant response. We developed a model of venous thrombosis that resulted in localized thrombus formation without disseminated intravascular coagulation. The model involves infusion of tumor necrosis factor, blockade of protein C and a partial decrease in venous flow caused by ligation of the superficial femoral vein without obstruction of the deep femoral vein. Infusion of phospholipid vesicles into this model resulted in amplification of a localized thrombotic response into a consumptive response.

Seven different groups of animals were studied. The first three groups established the conditions necessary to produce deep vein thrombosis. The second four groups established the conditions necessary to produce disseminated intravascular coagulation. The infusion of phospholipid vesicles plus tumor necrosis factor and anti-protein C antibody resulted in consumption of fibrinogen, the production of thrombin/antithrombin complexes, a fall in platelet count, and venous thrombosis. Without ligation and catheterization phospholipid vesicles failed to produce the consumptive response. We conclude, therefore, that phospholipid vesicles can amplify a local thrombotic response into a consumptive response, and that vesiculation accompanying inflammation is one means by which localized coagulant activity may be amplified to produce disseminated intravascular coagulation.

Oxidative Stress and Cardiovascular Risk in Type 1 Diabetes Mellitus: Insights From the DCCT/EDIC Study

Background

Hyperglycemia leading to increased oxidative stress is implicated in the increased risk for the development of macrovascular and microvascular complications in patients with type 1 diabetes mellitus.

Methods and Results

A random subcohort of 349 participants was selected from the DCCT / EDIC (Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications) cohort. This included 320 controls and 29 cardiovascular disease cases that were augmented with 98 additional known cases to yield a case cohort of 447 participants (320 controls, 127 cases). Biosamples from DCCT baseline, year 1, and closeout of DCCT , and 1 to 2 years post‐ DCCT ( EDIC years 1 and 2) were measured for markers of oxidative stress, including plasma myeloperoxidase, paraoxonase activity, urinary F 2α isoprostanes, and its metabolite, 2,3 dinor‐8 iso prostaglandin F 2α . Following adjustment for glycated hemoblobin and weighting the observations inversely proportional to the sampling selection probabilities, higher paraoxonase activity, reflective of antioxidant activity, and 2,3 dinor‐8 iso prostaglandin F 2α , an oxidative marker, were significantly associated with lower risk of cardiovascular disease (−4.5% risk for 10% higher paraoxonase, P <0.003; −5.3% risk for 10% higher 2,3 dinor‐8 iso prostaglandin F 2α , P =0.0092). In contrast, the oxidative markers myeloperoxidase and F 2α isoprostanes were not significantly associated with cardiovascular disease after adjustment for glycated hemoblobin. There were no significant differences between DCCT intensive and conventional treatment groups in the change in all biomarkers across time segments.

Conclusions

Heightened antioxidant activity (rather than diminished oxidative stress markers) is associated with lower cardiovascular disease risk in type 1 diabetes mellitus, but these biomarkers did not change over time with intensification of glycemic control.

Clinical Trial Registration

URL : https://www.clinicaltrials.gov . Unique identifiers: NCT 00360815 and NCT 00360893.

A two-stage approach to estimate spatial and spatio-temporal disease risks in the presence of local discontinuities and clusters

Disease risk maps for areal unit data are often estimated from Poisson mixed models with local spatial smoothing, for example by incorporating random effects with a conditional autoregressive prior distribution. However, one of the limitations is that local discontinuities in the spatial pattern are not usually modelled, leading to over-smoothing of the risk maps and a masking of clusters of hot/coldspot areas. In this paper, we propose a novel two-stage approach to estimate and map disease risk in the presence of such local discontinuities and clusters. We propose approaches in both spatial and spatio-temporal domains, where for the latter the clusters can either be fixed or allowed to vary over time. In the first stage, we apply an agglomerative hierarchical clustering algorithm to training data to provide sets of potential clusters, and in the second stage, a two-level spatial or spatio-temporal model is applied to each potential cluster configuration. The superiority of the proposed approach with regard to a previous proposal is shown by simulation, and the methodology is applied to two important public health problems in Spain, namely stomach cancer mortality across Spain and brain cancer incidence in the Navarre and Basque Country regions of Spain.

Hydro-nanofibrous mesh deep cell penetration: a strategy based on peeling of electrospun coaxial nanofibers

A two-step strategy for coaxial electrospinning and postelectrospinning is an effective method for fabricating superfine nanofibers composed of highly swellable hydrogels. Alginate and poly(ε-caprolactone) [PCL] were coelectrospun via fibrous meshes with a coaxial nozzle; alginate at the core was subsequently cross-linked in calcium chloride solution. The PCL sheath was removed from the meshes by repeated organic-phase washing. The peeling process was monitored by scanning electron microscopy, transmission electron microscopy, and differential scanning calorimetry, and the complete removal of the PCL outer layers was confirmed by the thinning of the fiber volume. The obtained alginate hydronanofiber showed extreme water-swellability and mass erosion depending on the degree of cross-linking. We also measured the nanoscale and macroscale mechanical properties of a single nanofiber and of the whole mesh by atomic force microscopy and rheometry. Quantitative analysis of nanomechanical properties indicated that the hydronanofiber with higher cross-linking density had higher stiffness and Derjaguin-Müller-Toporov modulus. Cells laid on the mesh and the vertical infiltration distance were visualized and quantified by confocal laser scanning microscopy. Cells on the mesh with higher cross-linking density infiltrated deeply to the bottom of the mesh. Thus, hydrogel-like nanofibrous meshes are versatile matrices allowing for deep infiltration of cells throughout the mesh via manipulation of the mechanical properties of the nanofiber.

Obesity increases the risk of small intestinal bacterial overgrowth (SIBO)

BACKGROUND

Small intestinal bacterial overgrowth (SIBO) has been associated with anatomical and motility-related abnormalities. Specifically, obesity has been postulated to alter small bowel motility, leading to SIBO.

AIMS

(i) Assess the prevalence of SIBO in obesity; (ii) determine the relationship of obesity and SIBO, using small bowel transit time (SBTT) and pH; (iii) profile the gut microbiome in obese and non-obese patients with SIBO.

METHODS

Thirty consecutive participants referred for SIBO underwent lactulose breath tests (LBTs) and wireless motility capsule (WMC) studies. Composition of the intestinal microbiome was assessed by analyzing samples from three different gastrointestinal sites via 16S rRNA gene-sequencing.

KEY RESULTS

SIBO was more frequent among obese patients vs non-obese patients (88.9% vs 42.9%, P < .05). Obesity did not correlate with small bowel transit time (SBTT), gastric pH, and small bowel pH. In patients with normal SBTT, obesity was associated with an 11-fold increase (P = .05) in the risk of SIBO. Whereas in those with prolonged SBTT, there was no correlation between obesity and SIBO. Obese vs non-obese patients exhibited significant differences in microbiome diversity in rectal samples. Obesity was associated with increased odds of developing SIBO (P = .04) in multivariate regression analyses.

CONCLUSIONS AND INFERENCES

While obesity was significantly associated with SIBO, our findings suggest that alterations in gut pH, SBTT, and decline in species richness do not account for the obesity-SIBO relationship.

Abstract PD3-04: Complete pathologic response rate to neoadjuvant chemotherapy increases with increasing HER2 ratio in HER2 over-expressing breast cancer: Analysis of the National cancer database (NCDB)

Background: HER2-positive (HER2+) breast cancer is an aggressive subtype that overexpresses human epidermal growth factor receptor 2 promoting cancer cell growth. Monoclonal antibodies targeting the HER2 receptor have improved survival for this patient population, and current NCCN guidelines recommend consideration of neoadjuvant anti-HER2 therapy (NAC) in Stage 2 & 3 HER2+ breast cancer. Pathologic complete response (pCR) to NAC has correlated with longer disease free survival in multiple trials.

Per ASCO-CAP guidelines tumors are considered HER2+ if HER2 copy number≥ 6/cell, HER2/CEP17 ratio≥ 2, or ratio&lt;2 & HER2 copy number ≥6/cell. We hypothesize that patients with higher HER2 ratios will have higher rates of pCR after NAC.

Methods: The National Cancer Database is supported by the American College of Surgeons and the American Cancer Society containing de-identified patient treatment data from over 1,500 US facilities. We performed a retrospective review comparing pCR rates after NAC based on HER2 ratio. Patients were excluded if they were HER2 negative, did not undergo NAC, or if the HER2 ratio was not recorded. Chi-squared and Fisher's exact test were used to compare pCR versus partial response between deciles of HER2 ratios.

Results: The NCDB included 237,118 patients with HER2 equivocal or HER2+ breast tumors. 29,291 of these patients underwent NAC, and HER2 ratios were recorded in 14,597 of the NAC cases. The majority (98%) of included cases were from 2010-2014. A pCR was noted in 9,752 patients and 11,402 patients had a partial response. No response was observed in 1,735 patients and 6,402 patients had a response but the degree was not recorded.

HER2 ratios were significantly different between pCR vs. partial response groups, p &lt;0.001. We identified a direct relationship between increasing HER2 ratio and response to NAC. For ratios 2-2.9, 23.6% achieved pCR and 44.7% had a partial response. For ratio of 5-5.9, 40.7% achieved pCR and even higher rates of pCR were noted for ratios 8-8.9; 49.5% achieved pCR. While both estrogen receptor (ER) positive and ER negative tumors demonstrated this trend, ER negative tumors had higher rates of pCR (ER negative pCR range 37.6% to 59.4% vs ER positive pCR range 16.9% to 42.3%, p&lt;0.01).

Conclusion: Contrary to current dogma, not all HER2+ tumors respond similarly to NAC. We demonstrate a linear relationship between HER2 ratio and pCR in over 14,000 patients. Those with HER2 ratios ≥5.0 were more likely to achieve pCR compared to patients with ratio ≤4.9. The NCDB reflects current clinical practice across the country not restricted to confines of clinical trials, and in this population higher HER2 ratios are predictive of pCR after NAC.

Response to NAC by Her2 Ratio- Complete vs Partial Response  Response to NAC   p ValueHER2 Ratio Complete Response- pCR (N) Partial Response (N)   1.00- 1.99141819.5%343047.2%&lt;0.01 2.00- 2.9951423.6%97444.7%&lt;0.01 3.00- 3.9928328.7%41942.4%&lt;0.01 4.00- 4.9926533.2%30638.2%&lt;0.01 5.00- 5.9929940.7%24333.1%&lt;0.01 6.00- 6.9929241.0%25435.5%&lt;0.01 7.00- 7.9924746.2%17432.5%&lt;0.01 8.00- 8.9918749.5%12132.0%&lt;0.01 9.00- 9.87 and greater44143.9%31431.3%&lt;0.01TOTAL 394627.0%623542.7%&lt;0.01

Citation Format: Greenwell K, Hussain L, Ho C, Dunki-Jacobs E, Lee D, Bramlage M, Bills G, Mehta A, Jones J, Jackson A, Wexelman B. Complete pathologic response rate to neoadjuvant chemotherapy increases with increasing HER2 ratio in HER2 over-expressing breast cancer: Analysis of the National cancer database (NCDB) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD3-04.

Multipoint scanning dual-detection confocal microscopy for fast 3D volumetric measurement

We propose a multipoint scanning dual-detection confocal microscopy (MS-DDCM) system for fast 3D volumetric measurements. Unlike conventional confocal microscopy, MS-DDCM can accomplish surface profiling without axial scanning. Also, to rapidly obtain 2D images, the MS-DDCM employs a multipoint scanning technique, with a digital micromirror device used to produce arrays of effective pinholes, which are then scanned. The MS-DDCM is composed of two CCDs: one collects the conjugate images and the other collects nonconjugate images. The ratio of the axial response curves, measured by the two detectors, provides a linear relationship between the height of the sample surface and the ratio of the intensity signals. Furthermore, the difference between the two images results in enhanced contrast. The normalising effect of the MS-DDCM provides accurate sample heights, even when the reflectance distribution of the surface varies. Experimental results confirmed that the MS-DDCM achieved high-speed surface profiling with improved image contrast capability.

Cell-sized lipid vesicles for cell-cell synaptic therapies

Cell-sized lipid vesicles (CLVs) have shown great promise for therapeutic and artificial cell applications, but their fragility and short shelf life has hindered widespread adoption and commercial viability. We present a method to circumvent the storage limitations of CLVs such as giant unilamellar vesicles (GUVs) and single-compartment multisomes (SCMs) by storing them in a double emulsion precursor form. The double emulsions can be stored for at least 8 months and readily converted into either GUVs or SCMs at any time. In this study, we investigate the interfacial parameters responsible for this morphological change, and we also demonstrate the therapeutic potential of CLVs by utilizing them to present a transmembrane protein, neuroligin-2, to pancreatic β-cells, forming cell-cell synapses that stimulate insulin secretion and cellular growth.

Measuring biotherapeutic viscosity and degradation on-chip with particle diffusometry

In the absence of efficient ways to test drug stability and efficacy, pharmaceuticals that have been stored outside of set temperature conditions are destroyed, often at great cost. This is especially problematic for biotherapeutics, which are highly sensitive to temperature fluctuations. Current platforms for assessing the stability of protein-based biotherapeutics in high throughput and in low volumes are unavailable outside of research and development laboratories and are not efficient for use in production, quality control, distribution, or clinical settings. In these alternative environments, microanalysis platforms could provide significant advantages for the characterization of biotherapeutic degradation. Here we present particle diffusometry (PD), a new technique to study degradation of biotherapeutic solutions. PD uses a simple microfluidic chip and microscope setup to calculate the Brownian motion of particles in a quiescent solution using a variation of particle image velocimetry (PIV) fundamentals. We show that PD can be used to measure the viscosity of protein solutions to discriminate native protein from degraded samples as well as to determine the change in viscosity as a function of therapeutic concentration. PD viscosity analysis is applied to two particularly important biotherapeutic preparations: insulin, a commonly used protein for diabetic patients, and monoclonal antibodies which are an emerging class of biotherapeutics used to treat a variety of diseases such as autoimmune disorders and cancer. PD-based characterization of solution viscosity is a new tool for biotherapeutic analysis, and owing to its easy setup could readily be implemented at key points of the pharmaceutical delivery chain and in clinical settings.

Broadband Surface Plasmon Lasing in One-dimensional Metallic Gratings on Semiconductor

We report surface plasmon (SP) lasing in metal/semiconductor nanostructures, where one-dimensional periodic silver slit gratings are placed on top of an InGaAsP layer. The SP nature of the lasing is confirmed from the emission wavelength governed by the grating period, polarization analysis, spatial coherence, and comparison with the linear transmission. The excellent performance of the device as an SP source is demonstrated by its tunable emission in the 400-nm-wide telecom wavelength band at room temperature. We show that the stimulated emission enhanced by the Purcell effect enables successful SP lasing at high energies above the gap energy of the gain. We also discuss the dependence of the lasing efficiency on temperature, grating dimension, and type of metal.