A Role of Effector CD 8 + T Cells Against Circulating Tumor Cells Cloaked with Platelets: Insights from a Mathematical Model.

Cancer metastasis accounts for a majority of cancer-related deaths worldwide. Metastasis occurs when the primary tumor sheds cells into the blood and lymphatic circulation, thereby becoming circulating tumor cells (CTCs) that transverse through the circulatory system, extravasate the circulation and establish a secondary distant tumor. Accumulating evidence suggests that circulating effector CD 8 + T cells are able to recognize and attack arrested or extravasating CTCs, but this important antitumoral effect remains largely undefined. Recent studies highlighted the supporting role of activated platelets in CTCs's extravasation from the bloodstream, contributing to metastatic progression. In this work, a simple mathematical model describes how the primary tumor, CTCs, activated platelets and effector CD 8 + T cells participate in metastasis. The stability analysis reveals that for early dissemination of CTCs, effector CD 8 + T cells can present or keep secondary metastatic tumor burden at low equilibrium state. In contrast, for late dissemination of CTCs, effector CD 8 + T cells are unlikely to inhibit secondary tumor growth. Moreover, global sensitivity analysis demonstrates that the rate of the primary tumor growth, intravascular CTC proliferation, as well as the CD 8 + T cell proliferation, strongly affects the number of the secondary tumor cells. Additionally, model simulations indicate that an increase in CTC proliferation greatly contributes to tumor metastasis. Our simulations further illustrate that the higher the number of activated platelets on CTCs, the higher the probability of secondary tumor establishment. Intriguingly, from a mathematical immunology perspective, our simulations indicate that if the rate of effector CD 8 + T cell proliferation is high, then the secondary tumor formation can be considerably delayed, providing a window for adjuvant tumor control strategies. Collectively, our results suggest that the earlier the effector CD 8 + T cell response is enhanced the higher is the probability of preventing or delaying secondary tumor metastases.

Fibrinogen binding to activated platelets and its biomimetic thrombus-targeted thrombolytic strategies.

Thrombosis is associated with various fatal arteriovenous syndromes including ischemic stroke, myocardial infarction, and pulmonary embolism. However, current clinical thrombolytic treatment strategies still have many problems in targeting and safety to meet the thrombolytic therapy needs. Understanding the molecular mechanism that underlies thrombosis is critical in developing effective thrombolytic strategies. It is well known that platelets play a central role in thrombosis and the binding of fibrinogen to activated platelets is a common pathway in the process of clot formation. Based on this, a concept of biomimetic thrombus-targeted thrombolytic strategy inspired from fibrinogen binding to activated platelets in thrombosis was proposed, which could selectively bind to activated platelets at a thrombus site, thus enabling targeted delivery and local release of thrombolytic agents for effective thrombolysis. In this review, we first summarized the main characteristics of platelets and fibrinogen, and then introduced the classical molecular mechanisms of thrombosis, including platelet adhesion, platelet activation and platelet aggregation through the interactions of activated platelets with fibrinogen. In addition, we highlighted the recent advances in biomimetic thrombus-targeted thrombolytic strategies which inspired from fibrinogen binding to activated platelets in thrombosis. The possible future directions and perspectives in this emerging area are briefly discussed.

Comparative analysis of the quality of platelet concentrates produced by apheresis procedures, platelet rich plasma, and buffy coat.

BACKGROUND: Platelet concentrates (PCs) could be prepared using either whole-blood processes or apheresis instruments. During collection, processing and storage, some biochemical and functional changes occur, which may result in quality reduction. Quality evaluation of PCs may be helpful for the precise control of platelet (PLT) inventory to reduce the risk of refractoriness and adverse effects caused by platelet transfusion. STUDY DESIGN AND METHODS: The study was aimed to evaluate the quality of PCs which were produced by five processes: apheresis (AP) procedures (using three different cell separators: Amicus, Trima Accel and MCS+ instruments), platelet rich plasma (PRP), and buffy coat (BC). A total of 100 PCs (20 of each group) were assessed in respect of routine quality control, morphology, size distribution, destroyed and activated platelets, and production of platelet-derived microparticles (PMPs). RESULTS: All PCs have satisfied the recommended quality of volume, platelet count, residual WBC count, residual RBC count, pH, and sterility according to the Chinese Technical Manual. There was no difference among the 5 groups in morphology and size of PLT and PMPs. Dynamic light scattering test showed that apheresis PCs showed peaks around 10-20 nm, but not whole blood-derived PCs. PCs prepared by Amicus had the relatively high percentage of destroyed platelet, activated platelets and PMPs than other groups. DISCUSSION: The data suggested high heterogeneity of PMPs, destroyed and activated platelets in PCs produced by different processes, which might be helpful to manage the platelet inventory for targeted use.

Adaptive changes in redox response and decreased platelet aggregation in lead-exposed workers.

Chronic lead exposure can generate pro-oxidative and pro-inflammatory conditions in the blood, related to high platelet activation and aggregation, altering cell functions. We studied ADP-stimulated aggregation and the oxidant/antioxidant system of platelets from chronically lead-exposed workers and non-exposed workers. Platelet aggregation was low in lead-exposed workers (62 vs. 97%), who had normal platelet counts and showed no clinical manifestations of hemostatic failure. ADP-activated platelets from lead-exposed workers failed to increase superoxide release (3.3 vs. 6.6 µmol/g protein), had low NADPH concentration (60 vs. 92 nmol/mg protein), high concentration of hydrogen peroxide (224 vs. 129 nmol/mg protein) and high plasma PGE2 concentration (287 vs. 79 pg/mL). Altogether, those conditions, on the one hand, could account for the low platelet aggregation and, on the other, indicate an adaptive mechanism for the oxidative status of platelets and anti-aggregating molecules to prevent thrombotic problems in the pro-oxidant and pro-inflammatory environment of chronic lead exposure.

Effects of diagnostic ultrasound with cRGD-microbubbles on simultaneous detection and treatment of atherosclerotic plaque in ApoE-/- mice.

Background: Atherosclerotic vulnerable plaque is the leading cause of acute fatal cardiovascular events. Thus, early rapid identification and appropriate treatment of atherosclerotic plaque maybe can prevent fatal cardiovascular events. However, few non-invasive molecular imaging techniques are currently available for the simultaneous detection and targeted treatment of atherosclerotic plaques. We hypothesized that diagnostic ultrasound (DU) combined with cyclic Arg-Gly-Asp-modified microbubbles (MBR) could provide targeted imaging and dissolution of activated platelets to identify advanced atherosclerotic plaques and improve plaque instability. Methods: Three mouse models, apolipoprotein E-deficient mice on a hypercholesterolemic diet (HCD) or normal chow diet and wild-type mice on an HCD were used. The most appropriate ultrasonic mechanical index (MI) was determined based on the expression of GP IIb/IIIa in sham, DU alone and DUMBR-treated groups at MI values of 0.5, 1.5, and 1.9. The video intensity (VI) values, activated platelets and plaque instability were analyzed by ultrasound molecular imaging, scanning electron microscopy and histopathological methods. Results: We found that the VI values of ultrasound molecular imaging of MBR were positively correlated with plaque GP IIb/IIIa expression, vulnerability index and necrotic center / fiber cap ratio. 24 h after treatment at different MIs, compared with those of the other groups, both the VI values and GP IIb/IIIa expression were significantly reduced in MI 1.5 and MI 1.9 DUMBR-treated groups. The plaque vulnerability index and necrotic center / fiber cap ratio were significantly decreased in MI 1.5-treated group, which may be due to targeted dissolution of activated platelets, with a reduction in von Willebrand factor expression. Conclusion: DUMBR targeting GP IIb/IIIa receptors could rapidly detect advanced atherosclerotic plaques and simultaneously give targeted therapy by dissolving activated and aggregated platelets. This technology may represent a novel approach for the simultaneous identification and treatment of atherosclerotic plaques.

Hyperadhesive von Willebrand Factor Promotes Extracellular Vesicle-Induced Angiogenesis: Implication for LVAD-Induced Bleeding.

Bleeding associated with left ventricular assist device (LVAD) implantation has been attributed to the loss of large von Willebrand factor (VWF) multimers to excessive cleavage by ADAMTS-13, but this mechanism is not fully supported by the current evidence. We analyzed VWF reactivity in longitudinal samples from LVAD patients and studied normal VWF and platelets exposed to high shear stress to show that VWF became hyperadhesive in LVAD patients to induce platelet microvesiculation. Platelet microvesicles activated endothelial cells, induced vascular permeability, and promoted angiogenesis in a VWF-dependent manner. Our findings suggest that LVAD-driven high shear stress primarily activates VWF, rather than inducing cleavage in the majority of patients.

Fucoidan-functionalized activated platelet-hitchhiking micelles simultaneously track tumor cells and remodel the immunosuppressive microenvironment for efficient metastatic cancer treatment.

Tumor metastasis is responsible for most mortality in cancer patients, and remains a challenge in clinical cancer treatment. Platelets can be recruited and activated by tumor cells, then adhere to circulating tumor cells (CTCs) and assist tumor cells extravasate in distant organs. Therefore, nanoparticles specially hitchhiking on activated platelets are considered to have excellent targeting ability for primary tumor, CTCs and metastasis in distant organs. However, the activated tumor-homing platelets will release transforming growth factor-ß (TGF-ß), which promotes tumor metastasis and forms immunosuppressive microenvironment. Therefore, a multitalent strategy is needed to balance the accurate tumor tracking and alleviate the immunosuppressive signals. In this study, a fucoidan-functionalized micelle (FD/DOX) was constructed, which could efficiently adhere to activated platelets through P-selectin. Compared with the micelle without P-selectin targeting effect, FD/DOX had increased distribution in both tumor tissue and metastasis niche, and exhibited excellent anti-tumor and anti-metastasis efficacy on 4T1 spontaneous metastasis model. In addition, due to the contribution of fucoidan, FD/DOX treatment was confirmed to inhibit the expression of TGF-ß, thereby stimulating anti-tumor immune response and reversing the immunosuppressive microenvironment. The fucoidan-functionalized activated platelets-hitchhiking micelle was promising for the metastatic cancer treatment.

Targeted Inhibition of Tumor Inflammation and Tumor-Platelet Crosstalk by Nanoparticle-Mediated Drug Delivery Mitigates Cancer Metastasis.

Sowing malignant cells (the "seeds" of metastasis) to engraft secondary sites requires a conducive premetastatic niche (PMN, the "soil" of metastasis). Inflammation and tumor associated platelet (TAP) has been hijacked by primary tumors to induce PMN "soil" in distant organs, as well as facilitate the dissemination of "seeds". This study reports a combinatory strategy with activated platelet-targeting nanoparticles to aim at the dynamic process of entire cancer metastasis, which exerts robust antimetastasis efficacy by simultaneously inhibiting tumor inflammation and tumor-platelet crosstalk. Our results reveals that the PSN peptide (a P-selectin-targeting peptide) modification enriched the accumulation of nanoparticles in primary tumor, pulmonary PMN, and metastases via capturing activated platelet. Such characteristics contribute to the efficient inhibition on almost every crucial and consecutive step of the metastasis cascade by retarding epithelial-mesenchymal transition (EMT) progression within tumors, specifically blocking the tumor-platelet crosstalk to remove the platelets "protective shield" around disseminated "seeds", and reversing the inflammatory microenvironment to interfere with the "soil" formation. Consisting of inflammation inhibiting and TAP impeding nanoparticles, this approach prominently reduces various metastasis in abscopal lung, including spontaneous metastasis, disseminated tumor cells metastasis, and post-operative metastasis. This work provides a generalizable nanoplatform of parallel inflammation disturbance and tumor-TAP crosstalk blockade to resist metastatic tumors.

Distribution and quantification of activated platelets in platelet-rich fibrin matrices.

Platelet-rich fibrin (PRF) has been widely applied in regenerative therapy owing to its simple preparation protocol. To date, the original protocol for preparing leukocyte-rich (L)-PRF has been modified to produce derivatives such as advanced (A)-PRF, concentrated growth factors (CGF), and horizontal (H)-PRF. However, these derivatives have not been rigorously compared to explore possible differences. We previously developed and validated a nondestructive near-infrared (NIR) imaging method to quantitatively examine the platelet distribution in PRF matrices. To further evaluate the characteristics of platelets in PRF, we herein examined the distribution of activated platelets. Four types of PRF matrices were prepared under different centrifugal conditions from blood samples obtained from the same healthy donors. After fixation and compression, the matrices were stained immunohistochemically without sectioning and visualized using an NIR imager. Qualitative morphological analysis revealed that whole platelets were distributed widely and homogeneously in H-PRF and A-PRF, but localized along the distal tube surface in L-PRF and CGF. Activated platelets were distributed as were whole platelets in A-PRF, L-PRF, and CGF, but localized mainly in the "buffy coat" region in H-PRF. Quantitative analysis revealed that there was no significant difference in the ratio of activated to whole platelets between PRF derivatives. These findings suggest that platelet activation is similarly induced in fibrin matrices regardless of centrifugal speed or rotor angulation. However, only the H-PRF group was distinguishable from the other PRF derivatives in terms of activated platelet distribution.

Fucoidan-functionalized activated platelet-hitchhiking micelles simultaneously track tumor cells and remodel the immunosuppressive microenvironment for efficient metastatic cancer treatment

Tumor metastasis is responsible for most mortality in cancer patients, and remains a challenge in clinical cancer treatment. Platelets can be recruited and activated by tumor cells, then adhere to circulating tumor cells (CTCs) and assist tumor cells extravasate in distant organs. Therefore, nanoparticles specially hitchhiking on activated platelets are considered to have excellent targeting ability for primary tumor, CTCs and metastasis in distant organs. However, the activated tumor-homing platelets will release transforming growth factor-β (TGF-β), which promotes tumor metastasis and forms immunosuppressive microenvironment. Therefore, a multitalent strategy is needed to balance the accurate tumor tracking and alleviate the immunosuppressive signals. In this study, a fucoidan-functionalized micelle (FD/DOX) was constructed, which could efficiently adhere to activated platelets through P-selectin. Compared with the micelle without P-selectin targeting effect, FD/DOX had increased distribution in both tumor tissue and metastasis niche, and exhibited excellent anti-tumor and anti-metastasis efficacy on 4T1 spontaneous metastasis model. In addition, due to the contribution of fucoidan, FD/DOX treatment was confirmed to inhibit the expression of TGF-β, thereby stimulating anti-tumor immune response and reversing the immunosuppressive microenvironment. The fucoidan-functionalized activated platelets-hitchhiking micelle was promising for the metastatic cancer treatment.

P2Y12 Inhibition in Murine Myocarditis Results in Reduced Platelet Infiltration and Preserved Ejection Fraction.

Previous mouse studies have shown the increased presence of platelets in the myocardium during early stages of myocarditis and their selective detection by MRI. Here, we aimed to depict early myocarditis using molecular contrast-enhanced ultrasound of activated platelets, and to evaluate the impact of a P2Y12 receptor platelet inhibition. Experimental autoimmune myocarditis was induced in BALB/c mice by subcutaneous injection of porcine cardiac myosin and complete Freund adjuvant (CFA). Activated platelets were targeted with microbubbles (MB) coupled to a single-chain antibody that binds to the "ligand-induced binding sites" of the GPIIb/IIIa-receptor (=LIBS-MB). Alongside myocarditis induction, a group of mice received a daily dose of 100 g prasugrel for 1 month. Mice injected with myosin and CFA had a significantly deteriorated ejection fraction and histological inflammation on day 28 compared to mice only injected with myosin. Platelets infiltrated the myocardium before reduction in ejection fraction could be detected by echocardiography. No selective binding of the LIBS-MB contrast agent could be detected by either ultrasound or histology. Prasugrel therapy preserved ejection fraction and significantly reduced platelet aggregates in the myocardium compared to mice without prasugrel therapy. Therefore, P2Y12 inhibition could be a promising early therapeutic target in myocarditis, requiring further investigation.

Hematological alterations in large Babesia species infection in dogs of Kannur District of Kerala.

Canine babesiosis is a tick-borne disease caused by apicomplexan intraerythrocytic hemoprotozoan parasites. It is caused by the small (Babesia gibsoni, B. conradae, and B. vulpes) and large (B. vogeli, B. canis, and B. rossi) Babesia groups. As per the recent reports, the most prominent Babesia species encountered in the Kerala state are the small Babesia, B. gibsoni followed by the large Babesia, B. vogeli. The latter is regarded as mildly pathogenic, causing subclinical or mild disease; however severe complications like systemic inflammatory response syndrome, multiple organ dysfunction syndrome, etc. have also been reported. The information on the status of hematological alterations in naturally infected dogs with large Babesia is lacking, particularly from the state of Kerala. The present study involves a retrospective study of clinical cases of large Babesia infection in dogs. The complete haematological profile from well-documented laboratory records of 4039 dogs suspected for babesiosis presented to District Veterinary Centre, Kannur during the period from December 2018 to October 2020 was analyzed for the study. Natural infections were recorded in 35 (0.87%) dogs based on the presence of intraerythrocytic piroplasm of large Babesia spp. by light microscopic examination of Giemsa-stained blood smears. The most consistent features observed were mild to moderate regenerative, normocytic and normochromic anemia, lowered to normal neutrophil count and thrombocytopenia. In comparison to hemolytic anemia, thrombocytopenia was the most frequent clinicopathological finding in the study with an increased presence of large activated platelets or macro-platelets.

Platelet-derived extracellular vesicles may contribute to the hypercoagulable state in preeclampsia.

It has previously been shown that preeclampsia is associated with disturbed hemostasis and that extracellular vesicles (EVs) play important role in the regulation of hemostatic homeostasis. Thus, we hypothesized that the altered procoagulant characteristics of circulating platelet-derived EVs may contribute to the disturbed hemostasis in preeclampsia. Using multicolor flow cytometry, we have analyzed both tissue factor expressing procoagulant EVs and platelet-derived EV subpopulations derived from resting and activated thrombocytes by examining them in plasma samples of preeclamptic patients and pregnancy-matched healthy individuals. Compared to pregnancy-matched healthy individuals in preeclamptic patients a significantly (p < 0.05) higher ratio of Annexin-V positive activated platelets and a higher number of CD142+ tissue factor bearing procoagulant EVs were found, whereas the absolute amount of circulating CD41a+ platelet-derived EVs and CD62P+/CD41a+ EVs produced by activated thrombocytes was significantly lower in the plasma of preeclamptic women. In the plasma samples, there was no significant difference in the amount of CD63+ platelet-derived EVs. We propose that increased platelet activation and tissue factor expression of platelet derived extracellular vesicles may contribute to the hypercoagulable state observed in preeclampsia.

Self-promoted Albumin-Based Nanoparticles for Combination Therapy against Metastatic Breast Cancer via a Hyperthermia-Induced "Platelet Bridge".

It has been a great challenge to simultaneously inhibit the outgrowth of both the primary tumor and metastasis in metastatic cancer treatment. Substantial studies have evidenced that the interaction of platelets and cancer cells supports tumor metastasis, and platelets are considered to have metastasis-targeting property. Inspired by injury-targeting and metastasis-targeting properties of platelets, we constructed a photothermal therapy strategy with activated platelet-targeting albumin-based nanoparticles, PSN-HSA-PTX-IR780, to amplify drug delivery in the primary tumor at mild temperatures and simultaneously inhibit metastasis via a "platelet bridge". Human serum albumin (HSA) was premodified with a P-selectin-targeting peptide (PSN peptide) or IR780 serving as a photosensitizer. Hybrid albumin nanoparticles were assembled via the disulfide reprogramming method and encapsulated paclitaxel (PTX) to formulate PSN-HSA-PTX-IR780. The PSN-modified albumin nanoparticles could bind with upregulated P-selectin on activated platelets and subsequently target cancer cells by using platelets as a "bridge". In addition, nanoparticle-generated hyperthermia induced tissue injury and increased tumor-infiltrating platelets, thereby recruiting more nanoparticles into the tumor in a self-promoted way. In vivo studies showed that the drug accumulation of PSN-HSA-PTX-IR780 was 2.86-fold higher than that of HSA-PTX-IR780 at the optimal temperature (45 °C), which consequently improved the therapeutic outcome. Moreover, PSN-HSA-PTX-IR780 also effectively targets and inhibits lung metastasis by binding with metastasis-infiltrating platelets. Altogether, the self-promoted nanoplatform provides a unique and promising strategy for metastatic cancer treatment with enhanced drug delivery efficacy.

Mechanisms Underlying Hepatocellular Carcinoma Progression in Patients with Type 2 Diabetes.

Hepatocellular carcinoma (HCC) ranks third in cancer-related deaths from solid tumors worldwide. The incidence of type 2 diabetes mellitus (T2DM) has increased worldwide in conjunction with the expansion of the Western lifestyle. Furthermore, patients with T2DM have been documented to have an increased risk of HCC, as well as bile tract cancer. Growing evidence shows that T2DM is a strong additive metabolic risk factor for HCC, but how diabetes affects the incidence of HCC requires additional investigation. In this review, we discuss the underlying mechanisms of HCC in patients with T2DM. Topics covered include abnormal glucose and lipid metabolism, hyperinsulinemia, and insulin resistance; the effect of activated platelets; hub gene expression associated with HCC; inflammation and signaling pathways; miRNAs; altered gut microbiota and immunomodulation. The evidence suggests that reducing obesity, diabetes, and nonalcoholic fatty liver disease/nonalcoholic steatohepatitis through efficient measures of prevention may lead to decreased rates of T2DM-related HCC.

Factor VIII and Factor V Membrane Bound Complexes.

The formation of membrane-bound complexes between specific coagulation factors at different cell surfaces is required for effective blood clotting. The most important of these complexes, the intrinsic Tenase and Prothrombinase complexes, are formed on the activated platelet surface during the propagation phase of coagulation. These two complexes are highly specific in their assembly mechanism and function modulated by anionic membranes, thus offering desirable targets for pharmaceutical interventions. Factor V (FV) and factor VIII (FVIII) are highly homologous non-enzymatic proteins. In their active state, FVa and FVIIIa serve as cofactors for the respective serine proteases factor Xa (FXa) and factor IXa (FIXa), significantly increasing their catalytic activity. This is achieved by forming well organized membrane-bound complexes at the phosphatidylserine rich activated platelet membrane in the presence of Ca2+ ions. The tenase (FVIIIa/FIXa) complex, catalyzes the proteolytic conversion of FX to FXa. Subsequently the prothrombinase (FVa/FXa) complex catalyzes the conversion of prothrombin to thrombin, required for efficient blood clotting. Although significant knowledge of FV and FVIII biochemistry and regulation has been achieved, the molecular mechanisms of their function are yet to be defined. Understanding the geometric assembly of the tenase and prothrombinase complexes is paramount in defining the structural basis of bleeding and thrombotic disorders. Such knowledge will enable the design of efficient pro- and anticoagulant therapies critical for regulating abnormal hemostasis. In this chapter, we will summarize the findings to date, showing our achievement in the field and outlining the future findings required to grasp the complexity of these proteins.

Mean Platelet Volume/Platelet Count Ratio is Associated with Poor Clinical Outcome After Aneurysmal Subarachnoid Hemorrhage.

BACKGROUND: Aneurysmal subarachnoid hemorrhage (aSAH) is both a hypercoagulable and inflammation state in which many biomarkers have been studied. Activated platelets have been identified to be of clinical importance in thrombosis and neuroinflammation after aSAH. The aim of this study was to investigate the relationship between mean platelet volume (MPV) to platelet count (PC) ratio, a surrogate parameter for activated platelets, and the functional outcome in aSAH patients. METHODS: A retrospective analysis was performed of patients with aSAH admitted to the stroke center of our institution between November 2018 and November 2019. The mean MPV/PC ratio during the first three days after aSAH onset was calculated. Poor outcome was defined as a modified Rankin Scale (mRS) score of 3-6 at 3 months. Receive operating characteristic (ROC) curve analysis was performed to determine the optimal value of MPV/PC ratio for the prediction of poor outcome in patients with aSAH. RESULTS: A total of 100 patients were included, 13 (13.0%) died and 35 (35.0%) had a poor outcome. Mean MPV/PC ratio (P < 0.001) when measured over the study period, was significantly higher among patients with poor outcome. In multivariable analysis, increased mean MPV/PC ratio was associated with poor functional outcome at 3 months (odds ratio (OR) = 1.94; 95% confidence interval (CI): 1.19-3.17; P = 0.008). The optimal cutoff of MPV/PC ratio for predicting poor outcome at 3 months was 6.77 (sensitivity 74.3%, specificity 61.5%). CONCLUSION: An increased MPV/PC ratio is associated with poor functional outcome in aSAH patients. MPV/PC ratio may be a useful predictor of outcome after aSAH.

Alterations to the contents of plasma membrane structural lipids are associated with structural changes and compartmentalization in platelets in hypertension.

Arterial hypertension (HTN) can lead to serious organ damage. Several mechanisms have been implicated in the pathogenesis of HTN including constitutive activation of platelets, which increases the risk of aggregation and clot formation. We recently demonstrated the plasma membranes of platelets from patients with HTN exhibit modified structural and physicochemical properties; Raman and Fourier transform infrared by attenuated total reflectance (FTIR-ATR) spectroscopy also indicated lipid content and protein structure alterations. This study aimed to precisely quantify the constituents of the main structural phospholipids and cholesterol in the plasma membranes of platelets from patients with HTN and normotensive individuals. We also assessed the consequence of these alterations on platelet structure and function. Liquid chromatography coupled to triple quadrupole mass spectrometry revealed the plasma membranes of HTN platelets contained less cholesterol and phosphatidylcholine, more phosphatidylserine and phosphatidylethanolamine and had similar sphingosine contents. Atomic force microscopy revealed HTN platelets exhibited increased surface roughness and more pleats. Transmission electron microscopy revealed diminution of the internal membranous structures in HTN platelets. Our findings strongly suggest plasma membrane lipid content alterations-including cholesterol depletion-occur in HTN, and these alterations may induce morphological and physiological abnormalities that participate in the functional changes associated with hypertension.

Cuboidal tethered cyclodextrin frameworks tailored for hemostasis and injured vessel targeting.

Rationale: Targeted delivery of therapeutic drugs or imaging agents to injured blood vessels via nanocarriers is likely to be dependent on the particle shape, yet cubic nanoparticle carriers have not been reported for vascular targeting. Here, we demonstrate that cuboidal cyclodextrin frameworks possess superior hemostasis effect and injured vessels targeting compared with spherical counterpart. Methods: Cuboidal and biocompatible γ-cyclodextrin metal-organic frameworks (CD-MOFs) are synthesized, tethered via crosslinking and surface modification with GRGDS peptide (GS5-MOFs). The specific interactions of cubic GS5-MOF nanoparticles with activated platelets were investigated by in vitro platelet aggregation assay and atomic force microscopy measurements (AFM). The hemostatic capacity and injured vessel targeting efficacy were evaluated in vivo. Results: Cuboidal GS5-MOF nanoparticles exhibit enhanced adhesion and aggregation with activated platelets in vitro under static condition and a physiologically relevant flow environment. The cubic GS5-MOF nanoparticles show efficient hemostatic effects with bleeding time and blood loss decrease of 90% and strong injured vessel targeting in vivo, markedly superior to spherical γ-CD nanosponges with the same chemical composition. Conclusions: These results clearly highlight the contribution of the cuboidal shape of GS5-MOFs to the enhanced aggregation of activated platelets and high targeting to damaged vessels. The cuboidal nanoparticle system provides an innovative delivery platform for the treatment and diagnosis of vascular diseases.

Combination of Preoperative D-Dimer and Platelet Distribution width Predicts Postoperative Deep Venous Thrombosis in Patients with Cervical Carcinoma

Background: Deep venous thrombosis (DVT) is associated with severe morbidity and mortality in cancer. Platelet distribution width (PDW), a platelet index, indicates variation in platelet size. We aimed to investigate whether the combination of D-dimer and PDW could have a better performance in predicting DVT in patients with cervical carcinoma. Materials and Methods: In 198 consecutive cervical carcinoma patients without preoperative DVT, preoperative D-dimer and PDW levels were measured. Compression ultrasonography was performed in all cervical carcinoma patients before surgery, as well as one month, three months, six months, and 12 months. Results: During a median period of 12 months, 17 of the 198 patients (8.6 %) developed DVT. PDW levels were reduced and D-dimer levels were increased in patients with DVT events compared to those without DVT. Multivariate Cox analysis revealed that both PDW and D-dimer were independent predictors for DVT events. The area under the ROC curve was 0.628 (95% CI: 0.556 to 0.695, p=0.142) when D-dimer was used alone, whereas it increased to 0.777 (95% CI: 0.712 to 0.833, p<0.011) with the addition of PDW. Incorporation of PDW into the D-dimer model significantly improved the predictive value. Conclusions: The combination of preoperative D-dimer and PDW improves the predictive power of postoperative DVT risk in patients with cervical carcinoma.