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This study examines the linkages between the upper-ocean (0–200 m) oxygen (O2) content and stratification in the North Pacific Ocean using four Earth system models (ESMs), an ocean hindcast simulation, and an ocean reanalysis. The trends and variability in oceanic O2 content are driven by the imbalance between physical supply and biological demand. Physical supply is primarily controlled by ocean ventilation, which is responsible for the transport of O2-rich surface waters to the subsurface. Isopycnic potential vorticity (IPV), a quasi-conservative tracer proportional to density stratification that can be evaluated from temperature and salinity measurements, is used herein as a dynamical proxy for ocean ventilation. The predictability potential of the IPV field is evaluated through its information entropy. The results highlight a strong O2–IPV connection and somewhat higher (as compared to the rest of the basin) predictability potential for IPV across the tropical Pacific, where the El Niño–Southern Oscillation occurs. This pattern of higher predictability and strong anticorrelation between O2 and stratification is robust across multiple models and datasets. In contrast, IPV at mid-latitudes has low predictability potential and its center of action differs from that of O2. In addition, the locations of extreme events or hotspots may or may not differ between the two fields, with a strong model dependency, which persists in future projections. On the one hand, these results suggest that it may be possible to monitor ocean O2 in the tropical Pacific based on a few observational sites co-located with the more abundant IPV measurements; on the other, they lead us to question the robustness of the IPV–O2 relationship in the extratropics. The proposed framework helps to characterize and interpret O2 variability in relation to physical variability and may be especially useful in the analysis of new observation-based data products derived from the BGC-Argo float array in combination with the traditional but far more abundant Argo data.

Observations and models indicate that climate warming is associated with the loss of dissolved oxygen from the ocean. Dissolved oxygen is a fundamental requirement for heterotrophic marine organisms (except marine mammals) and, since the basal metabolism of ectotherms increases with temperature, warming increases organisms' oxygen demands. Therefore, warming and deoxygenation pose a compound threat to marine ecosystems. In this study, we leverage an ecophysiological framework and a compilation of empirical trait data quantifying the temperature sensitivity and oxygen requirements of metabolic rates for a range of marine species (“ecotypes”). Using the Community Earth System Model Large Ensemble, we investigate how natural climate variability and anthropogenic forcing impact the ability of marine environments to support aerobic metabolisms on interannual to multi-decadal timescales. Warming and deoxygenation projected over the next several decades will yield a reduction in the volume of viable ocean habitats. We find that fluctuations in temperature and oxygen associated with natural variability are distinct from those associated with anthropogenic forcing in the upper ocean. Further, the joint temperature–oxygen anthropogenic signal emerges sooner than temperature and oxygen independently from natural variability. Our results demonstrate that anthropogenic perturbations underway in the ocean will strongly exceed those associated with the natural system; in many regions, organisms will be pushed closer to or beyond their physiological limits, leaving the ecosystem more vulnerable to extreme temperature–oxygen events.

The global ocean's oxygen content has declined significantly over the past several decades and is expected to continue decreasing under global warming, with far-reaching impacts on marine ecosystems and biogeochemical cycling. Determining the oxygen trend, its spatial pattern, and uncertainties from observations is fundamental to our understanding of the changing ocean environment. This study uses a suite of CMIP6 Earth system models to evaluate the biases and uncertainties in oxygen distribution and trends due to sampling sparseness. Model outputs are sub-sampled according to the spatial and temporal distribution of the historical shipboard measurements, and the data gaps are filled by a simple optimal interpolation method using Gaussian covariance with a constant e-folding length scale. Sub-sampled results are compared to full model output, revealing the biases in global and basin-wise oxygen content trends. The simple optimal interpolation underestimates the modeled global deoxygenation trends, capturing approximately two-thirds of the full model trends. The North Atlantic and subpolar North Pacific are relatively well sampled, and the simple optimal interpolation is capable of reconstructing more than 80 % of the oxygen trend in the non-eddying CMIP models. In contrast, pronounced biases are found in the equatorial oceans and the Southern Ocean, where the sampling density is relatively low. The application of the simple optimal interpolation method to the historical dataset estimated the global oxygen loss to be 1.5 % over the past 50 years. However, the ratio of the global oxygen trend between the sub-sampled and full model output has increased the estimated loss rate in the range of 1.7 % to 3.1 % over the past 50 years, which partially overlaps with previous studies. The approach taken in this study can provide a framework for the intercomparison of different statistical gap-filling methods to estimate oxygen content trends and their uncertainties due to sampling sparseness.

The molten salt synthesis has recently opened up new opportunities to functionalize two-dimensional MXenes with uniform halogen terminations. In this work, we synthesize Nb2CCl2 MXenes by etching the Al layer from the Nb2AlC precursor in the melt of CuCl2 Lewis acid. In Cl-terminated MXenes, intercalation of water is negligible, so that MXenes get closer to ideal, ordered van der Waals solids. We identify the preferential atomic stacking arrangement, which is of the AB type, as opposed to the AA stack assumed in previous works. We combine X-ray absorption near edge spectroscopy with density functional theory to clarify the local chemical environment of Cl atoms. Using vibrating sample magnetometry and specific heat measurements, we confirm that Nb2CCl2 MXenes are superconducting with a transition temperature of 6.0 K and find a Debye temperature of 320 K. We further show that the transition temperature slightly decreases with applied isostatic pressure.

Introduction In ESCAPE-TRD esketamine nasal spray (ESK-NS) significantly increased the probability of achieving remission at Week (Wk) 8 and being relapse‑free through Wk32 after remission at Wk8 versus (vs) quetiapine extended release (Q-XR) in patients (pts) with treatment resistant depression (TRD) (Reif et al. DGPPN 2022; P-01-04). We report ESK-NS vs Q-XR effects on pt-reported health-related quality of life (HRQoL) over 32 wks. Objectives Evaluate pt-reported HRQoL using the generic 36-item Short-Form Health Survey version 2 (SF-36v2, 4-wk recall, 2009 US population norms) in ESCAPE-TRD. Methods ESCAPE‑TRD (NCT04338321) was a randomised phase IIIb trial comparing the efficacy of ESK-NS vs Q-XR, both alongside an ongoing selective serotonin/serotonin-norepinephrine reuptake inhibitor, in pts with TRD. SF-36v2 was assessed every 4 wks (on-treatment and retrieved dropout visits). Domain scores and change from baseline (CfB) were analysed using a mixed model for repeated measures (MMRM; observed cases) adjusted for age, prior treatment failures, baseline score. Higher scores indicate better HRQoL. P values were not adjusted for multiple testing. Results 336 and 340 pts were randomised to ESK-NS and Q-XR. Baseline domain scores were below general population norms and lowest in Role Emotional, Mental Health and Social Functioning ( Figure 1A). All scores improved to Wk32 in both arms ( Figure 1B). At Wk4, CfB was significantly higher (better HRQoL) with ESK-NS vs Q-XR across domains (all p

Holography recreates both the amplitude and wave front of a three dimensional object, meaning that the observer perceives the image in the nearly same way as they would the true object. Creating such holographic images is challenging computationally, and requires extremely fast display update. Here, the authors combine a fast memoryless computation algorithm with the ultra-rapid writing based on all-optical switching of a ferrimagnetic film.

Introduction Treatment resistant depression (TRD) is estimated to affect 10–30% of patients with major depressive disorder (Al‑Harbi et al. Patient Prefer Adherence 2012; 6 369–88). Esketamine nasal spray (NS), in combination with a selective serotonin reuptake inhibitor (SSRI) or serotonin norepinephrine reuptake inhibitor (SNRI), increases remission and response rates in patients with TRD compared with placebo plus SSRI/SNRI (Popova et al. Am J Psychiatry 2019; 176 428–38). ESCAPE-TRD (NCT04338321) is the first randomised clinical trial to compare esketamine NS to quetiapine extended-release (XR), an antipsychotic augmentation therapy for patients with TRD. Objectives To explore the efficacy and safety of esketamine NS compared with quetiapine XR in TRD over 32 weeks (wks). Methods In the ESCAPE-TRD phase IIIb open-label, rater-blinded trial, patients were randomised 1:1 to esketamine NS (56/84 mg; twice per wk, weekly or every 2 wks) or quetiapine XR (150–300 mg daily) both in combination with an ongoing SSRI/SNRI. Remission (Montgomery-Åsberg Depression Rating Scale [MADRS] total score of ≤10) and response (≥50% improvement in MADRS total score from baseline or MADRS≤10) rates were analysed over time using last observation carried forward. MADRS change from baseline was analysed using Mixed Models for Repeated Measures (MMRM). The most common adverse events (AEs) leading to discontinuation are reported for patients who received ≥1 dose of study medication. Results At baseline, 336 patients were randomised to esketamine NS and 340 to quetiapine XR. A significantly higher percentage of patients in the esketamine NS group achieved remission (at each visit from Wk6 [p=0.008] onward) and response (at each visit from Day 15 [p

Hall transport and non-collinear magnetoresistance (NCMR) are studied for a chiral antiferromagnet (AFM) with the filled β-Mn-type structure. Magnetic and transport properties of epitaxial thin films of Co2−xPdxMo3N revealed that, in addition to a canted antiferromagnetic behavior above room temperature, thin films with x = 1.01∼1.38 exhibited a transition to a spin spiral state with a higher magnetic moment below TSR of around 50 K, which was assigned to a spin reorientation transition. The low-temperature phase shows both large anomalous Hall effect (AHE) and topological Hall effect (THE). Upon the transition to the canted AFM phase existing up to room temperature, the large AHE still persists with vanishing THE. The behavior of the Hall transport properties coupled with NCMR signals in the current-perpendicular-to-the plane configuration shows the formation of topological spin textures with locally antiferromagnetic order. The present results open the way for the study of topological antiferromagnetic spin textures, manipulation of their properties, and for future spintronic applications.

Western boundary currents act as transport pathways for nutrient-rich waters from low to high latitudes (nutrient streams) and are responsible for maintaining midlatitude and high-latitude productivity in the North Atlantic and North Pacific. This study investigates the centennial oxygen (O2) and nutrient changes over the Northern Hemisphere in the context of the projected warming and general weakening of the Atlantic Meridional Overturning Circulation (AMOC) in a subset of Earth system models included in the CMIP5 catalogue. In all models examined, the Atlantic warms faster than the Pacific Ocean, resulting in a greater basin-scale solubility decrease. However, this thermodynamic tendency is compensated by changes in the biologically driven O2 consumption which dominates the overall O2 budget. These changes are linked to the slowdown of the nutrient stream in this basin, in response to the AMOC weakening. The North Atlantic resists the warming-induced deoxygenation due to the weakened biological carbon export and remineralization, leading to higher O2 levels. Conversely, the projected nutrient stream and macronutrient inventory in the North Pacific remain nearly unchanged.

Recently, automatic feeders have become popular for collecting daily feed intake data in the pig industry, making it possible to evaluate genetic effects on feed efficiency and resilience traits, expressed as day-to-day fluctuations in feeding records. This study aimed to understand the influence of genetic factors on feed efficiency traits, including residual intake and BW gain (RIG), and resilience traits, as well as to compare the differences in genetic parameter estimates among three purebred pig breeds. A total of 6 103 pigs from three breeds (Large White: 1 193 pigs, Landrace: 3 010 pigs, and Duroc: 1 900 pigs) were raised in a specific pathogen-free environment. The growth and feed intake records during the testing period were obtained using automatic feeders, and the average daily gain (ADG) and average feed intake (AFI) were calculated. Feed conversion ratio (FCR), residual feed intake (RFI), residual gain, and RIG were calculated as feed efficiency traits, and the log-transformed variance of deviation for the daily feed intake (LnVar_FI), daily occupation time (LnVar_OC), and the daily number of visits to the feeder (LnVar_VT) was calculated as resilience traits. After estimating the genetic parameters for each breed, a meta-analysis was performed to obtain the weighted mean of heritability estimates (hm2) and genetic correlation estimates (GCm) for the three breeds. The hm2 were moderate and ranged from 0.31 to 0.39 for feed efficiency traits and 0.31 to 0.40 for resilience traits, and there were no significant differences in heritability estimates among the three breeds except for AFI, RFI, and RIG. For feed efficiency traits, the FCR and RIG showed favourably moderate GCm with AFI (0.29 and −0.33, respectively) and ADG (−0.39 and 0.31, respectively). For resilience traits, the LnVar_FI and LnVar_VT showed favourably low to moderate GCm with FCR (0.33 and 0.28, respectively) and RIG (−0.37 and 0.28, respectively), and there were no genetic relationships of LnVar_OC with FCR and RIG (the absolute value of GCm was 0.01). There was no significant difference in the genetic correlation estimates among the three breeds for feed efficiency and resilience traits. Our results suggest that feed efficiency and resilience traits were heritable, and resilience traits showed favourable or no genetic correlation with feed efficiency traits. In addition, the influence of genetic factors on feed efficiency and resilience traits could be the same among breeds.

Understanding the dynamics of cuprates following photoexcitation can provide insights into the complex coupling mechanisms that underlie their exotic equilibrium behaviour. Here the authors use pump-probe reflection spectroscopy to investigate the nonequilibrium spin dynamics of Mott-insulating Nd2CuO4.

The International Fusion Materials Irradiation Facility (IFMIF), presently in the Engineering Validation and Engineering Design Activities (EVEDA) phase was started from 2007 under the frame of the Broader Approach (BA) agreement. In the activities, a prototype Li loop with the world's highest flow rate of 3000L/min was constructed in 2010, and it succeeded in generating a 100mm wide and 25mm thick with a free-surface lithium flow along a concave back plate steadily at a high-speed of 15m/s at 250°C for 1300h. In the demonstration operation it was needed to develop the Li flowing measurement system with precious resolution less than 0.1mm, and a new wave height measuring method which is laser-probe method was developed for measurements of the 3D geometry of the liquid Li target surface. Using the device, the stability of the variation in the Li flowing thickness which is required in the IFMIF specification was ±1mm or less as the liquid Li target, and the result was satisfied with it and the feasibility of the long-term stable liquid Li flow was also verified. The results of the other engineering validation tests such as lithium purification tests of lithium target facility have also been evaluated and summarized.

It is well known that some sinkholes or subsidence take place from time to time in the areas where abandoned room and pillar type mines exist. The author has been involved with the stability of abandoned mines beneath urbanized residential areas in Tokai region and there is a great concern about the stability of these abandoned mines during large earthquakes as well as in the long term. The 2003 Miyagi Hokubu and 2011 Great East Japan earthquakes caused great damage to abandoned mines and resulted in many collapses. The author presents the effect of the depth and groundwater on the formation of sinkholes or ground subsidence associated with abandoned room and pillar lignite mines under static and dynamic conditions and discusses the implications on the areas above abandoned lignite mines in this paper.

The allelic frequency of c.335A>C polymorphisms in the porcine ghrelin/obestatin prepropeptide (GHRL) gene was surveyed among six pig breeds and two subspecies of wild boars. The c.335C was the most frequent allele in Berkshire, Landrace, Large White, Yorkshire, and Clawn miniature pigs and Ryukyu wild boars (Sus scrofa riukiuanus), whereas c.335A was the most frequent allele in Duroc and Meishan pigs and Japanese wild boars (S. s. leucomystax). The association of c.335A>C with performance traits was analyzed in Duroc, Landrace, Large White, and (Landrace × Large White) × Duroc (LWD) cross-bred pigs. No associations between c.335A>C genotype and average daily weight gain, backfat thickness, or intramuscular fat were detected. However, an association was observed between loin eye muscle area (EMA) and c.335A>C genotype in Duroc gilts. The AA genotype group had larger EMA than the AC genotype group in Duroc gilts; however, this association was not significant in Duroc boars and barrows or the other pig populations investigated. These results demonstrate that GHRL c.335A>C is not a major quantitative trait loci candidate on pig chromosome 13 affecting fat deposition.

No abstract available.

A 59-year-old male patient presented with left chest discomfort on admission. His medical history included encephalitis in childhood and his smoking history was 20 cigarettes per day for 40 years. A physical examination showed an anemic and edematous face with weak respiratory sounds in the left lung. The patient had elevated calcium levels and decreased hemoglobin and potassium. His parathyroid hormone-related protein level was elevated. Thoracic radiography showed cardiomegaly and computed tomography revealed a left lung mass with invasion of the heart and pleural effusion. Magnetic resonance imaging showed endocardial invasion of the tumor mass. Gallium-68 imaging revealed positive accumulation in the region surrounding the heart. No diagnoses were possible upon frequent cytology of his sputum and pleural effusion. The patient died from congestive heart failure with anoxia 38 days after admission. An autopsy revealed tumoral mass occlusion in the left main bronchus and tumoral invasion of the left atrium, left ventricle, and aorta.

A 94-year-old female patient presented with anorexia and left axillar lymphadenopathy on admission. Her past history was angina pectoris at 83 years of age and total gastrectomy due to gastric cancer at 87 years. The family history revealed that her son had had a malignant lymphoma, the histopathological diagnosis of which was diffuse large B-cell lymphoma. A physical examination showed both cervical, axillar, and inguinal lymphadenopathy without tenderness. She had elevated lactate dehydrogenase, ferritin, and soluble interleukin-2 receptor (sIL-2R). Whole-body computed tomography confirmed the cervical, axillary, and inguinal lymphadenopathy. Gallium-68 imaging revealed positive accumulation in these superficial lymph nodes. A right inguinal lymph node biopsy showed features of Epstein-Barr virus-associated lymphoproliferative disorder. Immunohistological studies on this lymph node biopsy showed CD20-positive large cells, CD3-positive small cells, and CD30-partly-positive large cells. In situ hybridization showed Epstein-Barr virus-positive, LMP-partly-positive, and EBNA2-negative cells. She refused chemotherapy as her son had died from hematemesis during chemotherapy. She received intravenous hyperalimentation for 1 month after admission. No palpable lymph nodes were identified by physical examination or computed tomography 3 months after admission, and regression of lactate dehydrogenase, ferritin, and sIL-2R was observed. She recovered from anorexia and was discharged. She died from pneumonia 10 months later after initial symptoms of anorexia. The autopsy showed no superficial lymphadenopathy.

No abstract available. doi:10.2204/iodp.sd.13.06.2011

The distribution of neuromyelitis optica (NMO)-characteristic brain lesions corresponds to sites of high aquaporin-4 (AQP4) expression, and the brainstem and hypothalamus lesions that express high levels of AQP4 protein are relatively characteristic of NMO. The syndrome of inappropriate antidiuretic hormone secretion (SIADH) is one of the important causes of hyponatremia and results from an abnormal production or sustained secretion of antidiuretic hormone (ADH). SIADH has been associated with many clinical states or syndromes, and the hypothalamic-neurohypophyseal system regulates the feedback control system for ADH secretion. We report the case of a 63-year-old man with NMO, whose initial manifestation was hyponatremia caused by SIADH. Retrospective analysis revealed that the serum anti-AQP4 antibody was positive, and an MRI scan showed a unilateral lesion in the hypothalamus. SIADH recovered completely with regression of the hypothalamic lesion. As such, NMO should even be considered in patients who develop SIADH and have no optic nerve or spinal cord lesions but have MRI-documented hypothalamic lesions.

The anti-allergic effect of an edible brown alga, Eisenia arborea, was investigated by determining the anti-degranulation activity on RBL cells or KU812 cells and the inhibitory effects on enzymatic activities involved in eicosanoid (leukotoriene and prostaglandin) synthesis. When the stimulated cells were treated with a M/C (methanol:chloroform = 1:2, v/v) extract of the alga, the histamine release of the cells was suppressed in a dose-dependent manner, and eicosanoid release from the cells was also strongly inhibited. Furthermore, the M/C extract and six phlorotannins (eckol, 6,6′-bieckol, 6,8′-bieckol, 8,8′-bieckol, phlorofucofuroeckol-A, phlorofucofuroeckol-B) derived from the extract inhibited enzymatic activities responsible for eicosanoid synthesis. This is the first report of the enzymatic activity inhibition by the phlorotannins 6,6′-bieckol, 6,8′-bieckol and PFF-B. Since histamine and eicosanoids are known to mediate the allergic reaction, inhibition of these mediators and enzymatic activities could be responsible for the anti-allergic effect of the alga.

No abstract available. doi:10.2204/iodp.sd.7.04.2009

No abstract available. doi:10.2204/iodp.sd.s01.38.2007

We present a novel technique based on a multi-resolutional clustering and nonlinear multi-dimensional scaling of earthquake patterns to investigate observed and synthetic seismic catalogs. The observed data represent seismic activities around the Japanese islands during 1997-2003. The synthetic data were generated by numerical simulations for various cases of a heterogeneous fault governed by 3-D elastic dislocation and power-law creep. At the highest resolution, we analyze the local cluster structures in the data space of seismic events for the two types of catalogs by using an agglomerative clustering algorithm. We demonstrate that small magnitude events produce local spatio-temporal patches delineating neighboring large events. Seismic events, quantized in space and time, generate the multi-dimensional feature space characterized by the earthquake parameters. Using a non-hierarchical clustering algorithm and nonlinear multi-dimensional scaling, we explore the multitudinous earthquakes by real-time 3-D visualization and inspection of the multivariate clusters. At the spatial resolutions characteristic of the earthquake parameters, all of the ongoing seismicity both before and after the largest events accumulates to a global structure consisting of a few separate clusters in the feature space. We show that by combining the results of clustering in both low and high resolution spaces, we can recognize precursory events more precisely and unravel vital information that cannot be discerned at a single resolution.

Abstract preview not available - see full-text PDF article.

Freshwater wetlands are groundwater-dependent ecosystems that require groundwater for saturation, for wetland plants and creatures, for maintenance of wetland soils, and thermal buffering. With worldwide wetland area in decline for decades if not centuries, finding and restoring wetlands provides enormous ecosystem and public benefits, yet so often these projects fail to yield self-sustaining wetland ecosystems. One reason is that restored wetlands are often built in places that are neither wet enough nor possess the underlying geology to sustain them, and they dry out or require continual (expensive!) water inputs. Massachusetts is making the best of a challenging situation for the declining cranberry farming industry: while competition from less expensive land and more productive varietals shifts cranberry production to other locations, everything under historic cranberry farms is ripe for resilient wetland restoration projects. These low-lying water-rich areas are underlain by glacial geology (peats and clays) that are ideal for holding water, they possess historic seed banks of wetland plants and large accumulations of organic and hydric soils, and are currently sought-after by a statewide restoration program, for which these results provide critical information for restoration design, enabling practitioners to maximize the capture and residence time of groundwater inputs to sustain the future wetland. In this paper, we investigate the human legacy of cranberry farming on the surface of a wetland as it has created a unique hydrogeologic unit: the anthropogenic aquifer. Water moves through an anthropogenically constructed aquifer in specific and predictable ways that were engineered to favor a monoculture of cranberry plants on the surface of what once was a peatland. In order to restore this landscape to a functioning freshwater wetland, every property of the anthropogenic aquifer must be reversed. We detail observational, thermal, hydrologic, geologic and isotopic evidence for the location of groundwater inflows to Foothills Preserve in southeastern Massachusetts. The specific properties of the Anthropogenic aquifer, and the location and magnitude of groundwater discharge at this location provide crucial information for practitioners when designing plans for a self-sustaining, resilient restored freshwater wetland on this and future sites.

Spatial navigation requires landmark coding from two perspectives, relying on viewpoint-invariant and self-referenced representations. The brain encodes information within each reference frame but their interactions and functional dependency remains unclear. Here we investigate the relationship between neurons in the rat's retrosplenial cortex (RSC) and entorhinal cortex (MEC) that increase firing near boundaries of space. Border cells in RSC specifically encode walls, but not objects, and are sensitive to the animal’s direction to nearby borders. These egocentric representations are generated independent of visual or whisker sensation but are affected by inputs from MEC that contains allocentric spatial cells. Pharmaco- and optogenetic inhibition of MEC led to a disruption of border coding in RSC, but not vice versa, indicating allocentric-to-egocentric transformation. Finally, RSC border cells fire prospective to the animal’s next motion, unlike those in MEC, revealing the MEC-RSC pathway as an extended border coding circuit that implements coordinate transformation to guide navigation behavior.

Background The clinical aspects of sickle cell anemia (SCA) are heterogeneous, and different patients may present significantly different clinical evolutions. Almost all organs can be affected, particularly the central nervous system. Transient ischemic events, infarcts, and cerebral hemorrhage can be observed and affect ≈25% of the patients with SCA. Differences in the expression of molecules produced by endothelial cells may be associated with the clinical heterogeneity of patients affected by vascular diseases. In this study, we investigated the differential expression of genes involved in endothelial cell biology in SCA patients with and without stroke. Methods and Results Endothelial progenitor cells from 4 SCA patients with stroke and 6 SCA patients without stroke were evaluated through the polymerase chain reaction array technique. The analysis of gene expression profiling identified 29 differentially expressed genes. Eleven of these genes were upregulated, and most were associated with angiogenesis (55%), inflammatory response (18%), and coagulation (18%) pathways. Downregulated expression was observed in 18 genes, with the majority associated with angiogenesis (28%), apoptosis (28%), and cell adhesion (22%) pathways. Remarkable overexpression of the MMP1 (matrix metalloproteinase 1) gene in the endothelial progenitor cells of all SCA patients with stroke (fold change: 204.64; P=0.0004) was observed. Conclusions Our results strongly suggest that angiogenesis is an important process in sickle cell stroke, and differences in the gene expression profile of endothelial cell biology, especially MMP1, may be related to stroke in SCA patients.