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991.
Platelets and their granular contents influence both angiogenesis and breast cancer progression. This study was performed to assess the effect of breast cancer and its treatment on platelet biology and the response to inhibition of the platelet P2Y12 receptor. Receptor-specific platelet activation and inhibition was studied for three platelet-associated proteins important in cancer angiogenesis and progression, vascular endothelial growth factor (VEGF), thrombospondin1 (TSP1), and transforming growth factor beta 1 (TGF-β1).

Twenty-four women with active breast cancer and 10 healthy controls not receiving antiplatelet therapy participated in the study. Ex vivo activation of platelets in whole blood was accomplished using PAR1AP, PAR4AP, convulxin, and ADP. Platelet inhibition was accomplished using the P2Y12 receptor antagonist cangrelor (the in vitro equivalent of clopidogrel). VEGF, TSP1, and TGF-β1 were measured using standard ELISA.

Platelet activation by ADP, PAR1, PAR4, and collagen receptors increased VEGF, TSP1, and TGF-β1 secretion in patients with breast cancer. Agonist-induced release of VEGF was greater in cancer patients as compared to healthy controls (p = 0.02 for ADP, p < 0.001 for PAR1AP, PAR4AP, and convulxin) despite a decrease in the efficiency of VEGF secretion in patients with breast cancer. These differences were not observed for TSP1 and TGF-β1 secretion. P2Y12 receptor inhibition decreased VEGF, TSP1, and TGF-β1 secretion. In patients with cancer, cangrelor inhibited TSP1 release to a greater extent than VEGF and TGF-β1 release. In patients with breast cancer, the magnitude of platelet inhibition achieved by cangrelor was greater than that achieved with healthy controls for all agonists and platelet proteins studied.

While platelets are known to influence progression of breast cancer, our results show that breast cancer and its treatment influence the platelet phenotype by increasing the secretion of pro-angiogenic proteins following platelet activation, modulating the efficiency of platelet protein release as well as increasing the response to antiplatelet therapy.  相似文献   

992.
Left ventricular hypertrophy (LVH) is prevalent among hypertensive children; however, blood pressure (BP) does not predict its presence. The authors conducted a 1‐year prospective cohort study to examine the hypothesis that obesity‐related risk factors are associated with left ventricular mass index (LVMI) in hypertensive children, and the association between adiposity and LVMI is mediated by BP‐dependent and ‐independent pathways. A total of 49 hypertensive children were enrolled: 51% were overweight/obese and 41% had LVH at baseline. Children overweight/obese at baseline and follow‐up had a greater LVMI increase than those of healthy weight at each visit: mean change of 6.4 g/m2.7 vs 0.95 g/m2.7. Baseline body mass index z score was independently associated with LVMI change (β=4.08, 1.54–6.61; P=.002). Only pulse pressure and serum aldosterone partially mediated this relationship. Hypertensive youth manifest multiple cardiovascular disease risk factors that worsen over time despite treatment. Of these, adiposity is most associated with LVH and increasing LVMI.  相似文献   
993.
Italy’s second wave of SARS-CoV-2 has hit hard, with more than three million cases and over 100,000 deaths, representing an almost ten-fold increase in the numbers reported by August 2020. Herein, we present an analysis of 6515 SARS-CoV-2 sequences sampled in Italy between 29 January 2020 and 1 March 2021 and show how different lineages emerged multiple times independently despite lockdown restrictions. Virus lineage B.1.177 became the dominant variant in November 2020, when cases peaked at 40,000 a day, but since January 2021 this is being replaced by the B.1.1.7 ‘variant of concern’. In addition, we report a sudden increase in another documented variant of concern—lineage P.1—from December 2020 onwards, most likely caused by a single introduction into Italy. We again highlight how international importations drive the emergence of new lineages and that genome sequencing should remain a top priority for ongoing surveillance in Italy.  相似文献   
994.
995.
Malignant lymphoma particularly of T phenotype can be associated with specific or non specific cutaneous lesions. These cutaneous manifestations can occur at the onset of the disease being sometimes the revealing sign or they can appear during the course of the lymphoreticular malignancies. Glomerulonephritis was also described in lymphoma. Ki- positive large cell lymphoma was recently identified. A new case is reported with lymphadenopathy and intestinal localisation revealed by cutaneous and mucosal ulcerations principally in the mouth and a focal segmental glomerulonephritis with endo- and extracapillary proliferation. The absence of lymphoma in cutaneous and renal lesions and the clinical presentation support the hypothesis of paraneoplastic manifestations, may be related to a vasculitis.  相似文献   
996.
In 990, Anhalt et al described a newly autoimmune billious disease: paraneoplastic pemphigus, in five patients. It was characterized by a distinct set of circulating autoantibodies from those in the sera of patients with pemphigus vulgaris and superficial pemphigus. We report a 7 year-old man with chronic lymphocytic leukemia of years duration who developed a severe mucocutaneous eruption with clinical and immunofluorescence findings of pemphigus vulgaris evolving into an oral bullous lichen planus presentation. Evaluation of his serum confirmed the presence of autoantibodies specific for paraneoplastic pemphigus by indirect immunofluorescence on rat-bladder and immunoprécipitation. Subsequently, additional cases have been reported in the literature. All occured in patients with various neoplastic conditions. These patients present with polymorphous skin lesions and severe erosive oral disease. Histologic examination shows interface dermatitis and keratinocyte necrosis in addition to acantolysis. Direct immunofluorescence may reveal deposition of immunoglobulin and/or complement at the basement membrane as well as deposition on epithelial cell surfaces. Circulating IgG anti-cell-surface antibodies are detectable with both stratified and stratified epithelia as substrates. These antibodies immunoprecipitate a complex of four desmosomal proteins, including desmoplakin I (50 kDa), the bullous pemphigoid antigen (0 kDa), desmoplakin II (0 kDa) and a 90 kDa antigen.  相似文献   
997.
Census data on endangered species are often sparse, error-ridden, and confined to only a segment of the population. Estimating trends and extinction risks using this type of data presents numerous difficulties. In particular, the estimate of the variation in year-to-year transitions in population size (the "process error" caused by stochasticity in survivorship and fecundities) is confounded by the addition of high sampling error variation. In addition, the year-to-year variability in the segment of the population that is sampled may be quite different from the population variability that one is trying to estimate. The combined effect of severe sampling error and age- or stage-specific counts leads to severe biases in estimates of population-level parameters. I present an estimation method that circumvents the problem of age- or stage-specific counts and is markedly robust to severe sampling error. This method allows the estimation of environmental variation and population trends for extinction-risk analyses using corrupted census counts--a common type of data for endangered species that has hitherto been relatively unusable for these analyses.  相似文献   
998.

Purpose of Review

To highlight the various applications of 3D printing in cardiovascular disease and discuss its limitations and future direction.

Recent Findings

Use of handheld 3D printed models of cardiovascular structures has emerged as a facile modality in procedural and surgical planning as well as education and communication.

Summary

Three-dimensional (3D) printing is a novel imaging modality which involves creating patient-specific models of cardiovascular structures. As percutaneous and surgical therapies evolve, spatial recognition of complex cardiovascular anatomic relationships by cardiologists and cardiovascular surgeons is imperative. Handheld 3D printed models of cardiovascular structures provide a facile and intuitive road map for procedural and surgical planning, complementing conventional imaging modalities. Moreover, 3D printed models are efficacious educational and communication tools. This review highlights the various applications of 3D printing in cardiovascular diseases and discusses its limitations and future directions.
  相似文献   
999.

Purpose of Review

Dengue continues to be a major global public health threat. Symptomatic infections can cause a spectrum of disease ranging from a mild febrile illness to severe and potentially life-threatening manifestations. Management relies on supportive treatment with careful fluid replacement. The purpose of this review is to define the unmet needs and challenges in current dengue diagnostics and patient monitoring and outline potential novel technologies to address these needs.

Recent Findings

There have been recent advances in molecular and point-of-care (POC) diagnostics as well as technologies including wireless communication, low-power microelectronics, and wearable sensors that have opened up new possibilities for management, clinical monitoring, and real-time surveillance of dengue.

Summary

Novel platforms utilizing innovative technologies for POC dengue diagnostics and wearable patient monitors have the potential to revolutionize dengue surveillance, outbreak response, and management at population and individual levels. Validation studies of these technologies are urgently required in dengue-endemic areas.
  相似文献   
1000.
Coronary embolism is the underlying cause of 3% of acute coronary syndromes but is often not considered in the differential of acute coronary syndromes. It should be suspected in the case of high thrombus burden despite a relatively normal underlying vessel or recurrent coronary thrombus. Coronary embolism may be direct (from the aortic valve or left atrial appendage), paroxysmal (from the venous circulation through a patent foramen ovale), or iatrogenic (following cardiac intervention). Investigations include transesophageal echocardiography to assess the left atrial appendage and atrial septum and continuous electrocardiographic monitoring to assess for paroxysmal atrial fibrillation. The authors review the historic and contemporary published data about this important cause of acute coronary syndromes. The authors propose an investigation and management strategy for work-up and anticoagulation strategy for patients with suspected coronary embolism.  相似文献   
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