Nanogold-coated stent facilitated non-invasive photothermal ablation of stent thrombosis and restoration of blood flow.

In-stent restenosis (ISR) and stent thrombosis (ST) are the most serious complications of coronary angioplasty and stenting. Although the evolution of drug-eluting stents (DES) has significantly restricted the incidence of ISR, they are associated with an enhanced risk of ST. In the present study, we explore the photothermal ablation of a thrombus using a nano-enhanced thermogenic stent (NETS) as a modality for revascularization following ST. The photothermal activity of NETS, fabricated by coating bare metal stents with gold nanorods generating a thin plasmonic film of gold, was found to be effective in rarefying clots formed within the stent lumen in various in vitro assays including those under conditions mimicking blood flow. NETS implanted in the rat common carotid artery generated heat following exposure to a NIR-laser that led to effective restoration of blood flow within the occluded vessel in a model of ferric chloride-induced thrombosis. Our results present a proof-of-concept for a novel photothermal ablation approach by employing coated stents in the non-invasive management of ST.

Non-canonical non-genomic morphogen signaling in anucleate platelets: a critical determinant of prothrombotic function in circulation.

Circulating platelets derived from bone marrow megakaryocytes play a central role in thrombosis and hemostasis. Despite being anucleate, platelets express several proteins known to have nuclear niche. These include transcription factors and steroid receptors whose non-genomic functions are being elucidated in platelets. Quite remarkably, components of some of the best-studied morphogen pathways, namely Notch, Sonic Hedgehog (Shh), and Wnt have also been described in recent years in platelets, which regulate platelet function in the context of thrombosis as well as influence their survival. Shh and Notch pathways in stimulated platelets establish feed-forward loops of autocrine/juxtacrine/paracrine non-canonical signaling that helps perpetuate thrombosis. On the other hand, non-canonical Wnt signaling is part of a negative feedback loop for restricting platelet activation and possibly limiting thrombus growth. The present review will provide an overview of these signaling pathways in general. We will then briefly discuss the non-genomic roles of transcription factors and steroid receptors in platelet activation. This will be followed by an elaborate description of morphogen signaling in platelets with a focus on their bearing on platelet activation leading to hemostasis and thrombosis as well as their potential for therapeutic targeting in thrombotic disorders.

Platelet functions in lymphatic filariasis patients.

Filariasis is a chronic disease where parasitic worms survive in human hosts even for decades and lead to complications like lymphedema and elephantiasis. Despite the persistent existence of filarial parasites in human hosts, fatal and thrombotic complications are not known, unlike other parasitic diseases like malaria. This suggests that filarial parasites might be affecting the host's platelet functions. This study was conducted to examine platelet functions in confirmed filariasis patients and healthy controls. Results showed that filariasis patients had larger platelets, inhibited aggregation, and slower speed of aggregation, compared to controls. However, in vivo markers of platelet activation and degranulation (beta thromboglobulin and soluble P-selectin) were not affected. Observations suggested that there is increased platelet turnover, cellular apoptosis and inhibited platelet functions in filariasis patients compared to controls. Platelet function inhibition was not associated with the duration of disease, lymphedema-affected organs, or gender of patients. This study confirms that filarial parasites modulate platelet functions in human hosts.

Nattokinase Encapsulated Nanomedicine for Targeted Thrombolysis: Development, Improved in Vivo Thrombolytic Effects, and Ultrasound/Photoacoustic Imaging.

Nattokinase (NK), a potent thrombolytic enzyme that dissolves blood clots, is highly used in the treatment of cardiovascular disorders. However, its effective delivery remains demanding because of stability and bioavailability problems owing to its high molecular weight and proteineous nature. In this research, we have developed novel NK-loaded nontargeted liposomes (NK-LS) and targeted liposomes (RGD-NK-LS and AM-NK-LS) by the reverse phase evaporation method. The physiochemical characterizations (particle size, polydispersity index, zeta potential, and morphology) were performed by a Zetasizer, SEM, TEM, and AFM. The Bradford assay and XPS analysis confirmed the successful surface conjugation of the targeting ligands. Platelet interaction studies by CLSM, photon imager optima, and flow cytometry showed significantly higher (P < 0.05) platelet binding affinity of targeted liposomes. In vitro evaluations were performed using human blood and a fibrinolysis study by CLSM imaging demonstrating the potent antithrombotic efficacy of AM-NK-LS. Furthermore, bleeding and clotting time studies revealed that the targeted liposomes were free from any bleeding complications. Moreover, the in vivo FeCl3 model on Sprague-Dawley (SD) rats using a Doppler flow meter and ultrasound/photoacoustic imaging indicated the increased % thrombolysis and potent affinity of targeted liposomes toward the thrombus site. Additionally, in vitro hemocompatibility and histopathology studies demonstrated the safety and biocompatibility of the nanoformulations.

Introducing the new face of CLSI M100 in 2023: An explanatory review.

BACKGROUND: The CLSI annual update of its M100 document is eagerly awaited every year. This year's update, the M100-Ed33, was published in February, and will significantly affect clinical practices. OBJECTIVE: To highlight and explain the rationale of the changes and their clinical impact. CONTENT: The major changes this year are mostly focused on PK/PD data, selective and cascade reporting of the antibiotics and therapy related comments. The CLSI has moved away from its classical grouping of antibiotics (A, B, U, O) to a tier-based approach (Tier 1, 2, 3, 4) which will aid in cascade reporting during an antibiotic susceptibility testing (AST). Rather than non-fastidious, fastidious and anaerobe grouping, the tables have been made organism specific. The aminoglycosides breakpoints have been changed for both Enterobacterales and Pseudomonas aeruginosa while for P. aeruginosa, the breakpoints of piperacillin - tazobactam (TZP) are also updated. These updates are mostly based on attainment of drug plasma level for bacterial stasis rather than bactericidal effect of the antibiotics. It is noteworthy, that these breakpoint changes are made, keeping in view that the aminoglycosides for all organisms should be used in combination therapy. For P. aeruginosa, gentamicin has been removed, while amikacin has been restricted for urinary isolates only.

Faecal calprotectin as an inflammatory biomarker to distinguish between bacterial and viral causes of childhood diarrhoea in Indian settings.

OBJECTIVES: The purpose of this study was to determine the value of faecal calprotectin (f-CP) in distinguishing between bacterial and viral aetiologies of infective diarrhoea in children attending a tertiary care hospital in Central India. METHODS: Stool samples from children aged 3 months to 10 years who had acute or persistent diarrhoea were processed for microscopy, bacterial culture, and viral antigen detection (Rotavirus and Norovirus). The remaining samples, as well as stool samples from 20 healthy controls, were tested for f-CP using the enzyme linked immunosorbent assay. RESULTS: Among 48 patients, 21 (43.7%) had bacterial diarrhoea, 14 (29.2%) had viral diarrhoea, and 13 (27.1%) had an unidentified aetiology. The median f-CP values were significantly (p â€‹= â€‹0.004) higher in children with bacterial diarrhoea (75.2 â€‹µg/g; IQR-18.75-239.15) than in children with viral diarrhoea (75.2 â€‹µg/g; IQR-123.5-1987.5). Bacterial aetiology could be reliably predicted at the optimum f-CP concentrations of >541 â€‹µg/g and >238.4 â€‹µg/g in children aged 1 and 1-4 years, with an area under the curve of 0.767 and 0.867, respectively, using receiver-operator characteristic analysis. CONCLUSIONS: Faecal calprotectin could reliably distinguish between bacterial and viral aetiologies of diarrhoea in children aged up to four years, but at relatively higher age-specified cut off values.

Glutamate Receptor Dysregulation and Platelet Glutamate Dynamics in Alzheimer's and Parkinson's Diseases: Insights into Current Medications.

Two of the most prevalent neurodegenerative disorders (NDDs), Alzheimer's disease (AD) and Parkinson's disease (PD), present significant challenges to healthcare systems worldwide. While the etiologies of AD and PD differ, both diseases share commonalities in synaptic dysfunction, thereby focusing attention on the role of neurotransmitters. The possible functions that platelets may play in neurodegenerative illnesses including PD and AD are becoming more acknowledged. In AD, platelets have been investigated for their ability to generate amyloid-ß (Aß) peptides, contributing to the formation of neurotoxic plaques. Moreover, platelets are considered biomarkers for early AD diagnosis. In PD, platelets have been studied for their involvement in oxidative stress and mitochondrial dysfunction, which are key factors in the disease's pathogenesis. Emerging research shows that platelets, which release glutamate upon activation, also play a role in these disorders. Decreased glutamate uptake in platelets has been observed in Alzheimer's and Parkinson's patients, pointing to a systemic dysfunction in glutamate handling. This paper aims to elucidate the critical role that glutamate receptors play in the pathophysiology of both AD and PD. Utilizing data from clinical trials, animal models, and cellular studies, we reviewed how glutamate receptors dysfunction contributes to neurodegenerative (ND) processes such as excitotoxicity, synaptic loss, and cognitive impairment. The paper also reviews all current medications including glutamate receptor antagonists for AD and PD, highlighting their mode of action and limitations. A deeper understanding of glutamate receptor involvement including its systemic regulation by platelets could open new avenues for more effective treatments, potentially slowing disease progression and improving patient outcomes.

Ayurvedic preparations of Raudra Rasa inhibit agonist-mediated platelet activation and restrict thrombogenicity without affecting cell viability.

Ayurveda is considered to be one of the most ancient forms of medicine still practiced. The Ayurvedic preparation Raudra Rasa and its derivatives have been widely employed against cancer since the 12th century, but the effect of these traditional formulations on platelet function and signaling has not previously been examined. Here we demonstrate that Raudra Rasa and its derivatives significantly reduce thrombin-induced integrin activation and granule secretion in platelets, as observed by reduced PAC-1 binding and P-selectin externalization, respectively. These formulations also inhibited thrombin-stimulated phosphatidylserine exposure, mitochondrial reactive oxygen species generation, and mitochondrial transmembrane potential in platelets. Consistent with the above, Raudra Rasa significantly reduced thrombin-induced tyrosine phosphorylation of the platelet proteins, as well as phosphorylation of the enzymes AKT and GSK-3ß. In summary, Raudra Rasa inhibits agonist-mediated platelet activation without affecting cell viability, suggesting it may have therapeutic potential as an anti-platelet/anti-thrombotic agent.

Comparative study on Saliva and Nasopharyngeal swabs and the outcome of RT-PCR test in patients with mild symptoms of SARS-CoV-2 / Estudio comparativo de muestras de saliva y nasofaríngeas y el resultado de la prueba RT-PCR en pacientes con síntomas leves de SARS-CoV-2

Aim A simple and reliable method for diagnosing COVID 19 infections is the needed. The role of saliva in the transmission of the infection has already been established. Method Saliva and nasopharyngeal swabs from patients suspected to have COVID 19 infections were taken simultaneously, and the results of the RT-PCR were compared. Result Total 405 samples were collected, of which 250 males and 155 females. In the 391 samples included for analysis, 370 (94.63%) samples were found to have concordance results, and 21 (5.37%) samples had discordant results. Conclusion The use of saliva to diagnose COVID 19 infection is reliable, and its use can be recommended. (AU)

Objetivo Un método simple y confiable para diagnosticar infecciones por COVID 19 es necesario. Ya se ha establecido el papel de la saliva en la transmisión de la infección. Método Se tomaron simultáneamente hisopos de saliva y nasofaríngeos de pacientes con sospecha de infección por COVID 19 y se compararon los resultados de la RT-PCR. Resultado Se recogieron 405 muestras, de las cuales 250 hombres y 155 mujeres. En las 391 muestras incluidas para el análisis, se encontró que 370 (94,63%) muestras tenían resultados de concordancia y 21 (5,37%) muestras tenían resultados discordantes. Conclusión El uso de la saliva para diagnosticar la infección por COVID 19 es confiable y se puede recomendar su uso. (AU)

Chitosan-g-estrone Nanoparticles of Palbociclib Vanished Hypoxic Breast Tumor after Targeted Delivery: Development and Ultrasound/Photoacoustic Imaging.

Breast cancer is the leading cause of death among women globally. Approximately 80% of all breast cancers diagnosed are overexpressed with estrogen receptors (ERs). In this study, we have developed an estrone (Egen)-grafted chitosan-based polymeric nanocarrier for the targeted delivery of palbociclib (PLB) to breast cancer. The nanoparticles (NPs) were prepared by solvent evaporation using the ionic gelation method and characterized for particle size, zeta potential, polydispersity, surface morphology, surface chemistry, drug entrapment efficiency, cytotoxicity assay, cellular uptake, and apoptosis study. The developed PLB-CS NPs and PLB-CS-g-Egen NPs had a particle size of 116.3 ± 1.53 nm and 141.6 ± 1.97 nm, respectively. The zeta potential of PLB-CS NPs and PLB-CS-g-Egen NPs was found to be 18.70 ± 0.416 mV and 12.45 ± 0.574 mV, respectively. The morphological analysis demonstrated that all NPs were spherical in shape and had a smooth surface. An in vitro cytotoxicity assay was performed in estrogen receptor (ER)-expressing MCF7 cells and T47D cells, which suggested that targeted NPs were 57.34- and 30.32-fold more cytotoxic compared to the pure PLB, respectively. Additionally, cell cycle analysis confirmed that cell cycle progression from the G1 into S phase was blocked more efficiently by targeted NPs compared to nontargeted NPs and PLB in MCF7 cells. In vivo pharmacokinetic studies demonstrated that entrapment of the PLB in the NPs improved the half-life and bioavailability by ∼2-3-fold. Further, ultrasound and photoacoustic imaging of DMBA induced breast cancer in the Sprague-Dawley (SD) rat showed that targeted NPs completely vanished breast tumor, reduced hypoxic tumor volume, and suppressed tumor angiogenesis more efficiently compared to the nontargeted NPs and free PLB. Further, in vitro hemocompatibility and histopathology studies suggested that NPs were biocompatible and safe for clinical use.

Necroptosis executioner MLKL plays pivotal roles in agonist-induced platelet prothrombotic responses and lytic cell death in a temporal order.

Necroptosis is a form of programmed cell death executed by receptor-interacting serine/threonine protein kinase 1 (RIPK1), RIPK3, and mixed lineage kinase domain-like (MLKL). Platelets are circulating cells that play central roles in haemostasis and pathological thrombosis. In this study we demonstrate seminal contribution of MLKL in transformation of agonist-stimulated platelets to active haemostatic units progressing eventually to necrotic death on a temporal scale, thus attributing a yet unrecognized fundamental role to MLKL in platelet biology. Physiological agonists like thrombin instigated phosphorylation and subsequent oligomerization of MLKL in platelets in a RIPK3-independent but phosphoinositide 3-kinase (PI3K)/AKT-dependent manner. Inhibition of MLKL significantly curbed agonist-induced haemostatic responses in platelets that included platelet aggregation, integrin activation, granule secretion, procoagulant surface generation, rise in intracellular calcium, shedding of extracellular vesicles, platelet-leukocyte interactions and thrombus formation under arterial shear. MLKL inhibition, too, prompted impairment in mitochondrial oxidative phosphorylation and aerobic glycolysis in stimulated platelets, accompanied with disruption in mitochondrial transmembrane potential, augmented proton leak and drop in both mitochondrial calcium as well as ROS. These findings underscore the key role of MLKL in sustaining OXPHOS and aerobic glycolysis that underlie energy-intensive platelet activation responses. Prolonged exposure to thrombin provoked oligomerization and translocation of MLKL to plasma membranes forming focal clusters that led to progressive membrane permeabilization and decline in platelet viability, which was prevented by inhibitors of PI3K/MLKL. In summary, MLKL plays vital role in transitioning of stimulated platelets from relatively quiescent cells to functionally/metabolically active prothrombotic units and their ensuing progression to necroptotic death.

Platelet function suggests cardioembolic aetiology in cryptogenic stroke.

Platelet-monocyte (PMA) and platelet-neutrophil aggregations (PNA) play critical roles in the evolution of acute ischemic stroke (AIS). The present study investigates the mechanistic basis of platelet responsiveness in cryptogenic stroke compared with cardioembolic stroke. Platelet from 16 subjects, each from cryptogenic and cardioembolic stroke groups and 18 age-matched healthy controls were subjected to different investigations. Compared to healthy controls, platelet-monocyte and platelet-neutrophil interactions were significantly elevated in cryptogenic (2.7 and 2.1 times) and cardioembolic stroke (3.9 and 2.4 times). P-selectin expression on platelet surface was 1.89 and 2.59 times higher in cryptogenic and cardioembolic strokes, respectively, compared to healthy control. Cell population with [Ca2+i] in either stroke group was significantly outnumbered (by 83% and 72%, respectively, in cryptogenic and cardioembolic stroke) in comparison to healthy controls. Noteworthy, TEG experiment revealed that the cryptogenic stroke exhibited significant decline in Reaction Time (R) and amplitude of 20 mm (K) (by 32% and 33%, respectively) while thrombin burst (α-angle) was augmented by 12%, which reflected substantial boost in thrombus formation in cryptogenic stroke. Although TEG analysis reveals a state of hypercoagulability in patients with cryptogenic stroke. However, platelets from both stroke subtypes switch to a 'hyperactive' phenotype.

Energy metabolism in platelets fuels thrombus formation: Halting the thrombosis engine with small-molecule modulators of platelet metabolism.

Platelets are circulating cells central to haemostasis that follows vessel injury, as well as thrombosis that ensues as a consequence of pathological stasis or plaque rupture. Platelet responses to various stimuli that mediate these processes are all energy-intensive. Hence, platelets need to adapt their energy metabolism to fulfil the requirements of clot formation while overcoming the adversities of the thrombus niche such as restricted access to oxygen and nutrient. In the present review, we describe the changes in energy metabolism of platelets upon agonist challenge and their underlying molecular mechanisms. We briefly discuss the metabolic flexibility and dependency of stimulated platelets in terms of choice of energy substrates. Finally, we discuss how targeting the metabolic vulnerabilities of stimulated platelets such as aerobic glycolysis and/or beta oxidation of fatty acids could forestall platelet activation and thrombus formation. Thus, we present a case for modulating platelet energy metabolism using small-molecules as a novel anti-platelet strategy in the management of vaso-occlusive disorders like acute myocardial infarction, ischemic stroke, deep vein thrombosis and pulmonary embolism.

Can Most Calcified Coronary Stenosis Be Optimized With Coronary Intravascular Lithotripsy?

Intravascular lithotripsy can be used as an effective therapy for lesion preparation in severely calcified lesions. The mechanism, as shown by optical coherence tomography, is calcium fractures. The aforementioned modification is performed with minimal risk of perforation, no-reflow and a low incidence of flow-limiting dissection and myocardial infarctions. Other techniques, such as cutting or scoring balloons and rotational atherectomy have also been shown to increase luminal diameter, but other complications, such as distal embolization, induced by these treatment modalities, are a source of concern. This review describes a single-center study of all-comer patients, including those with complex characteristics. This therapy is very effective, with a very low risk of complications. In this article, we characterize the mechanism of action of the intravascular lithotripsy catheter, its optical coherence tomography validation, clinical applications, and comparison with other calcium-modifying technologies, as well as future directions, which can be used to improve the technology.

Comparative study on Saliva and Nasopharyngeal swabs and the outcome of RT-PCR test in patients with mild symptoms of SARS-CoV-2.

AIM: A simple and reliable method for diagnosing COVID 19 infections is the needed. The role of saliva in the transmission of the infection has already been established. METHOD: Saliva and nasopharyngeal swabs from patients suspected to have COVID 19 infections were taken simultaneously, and the results of the RT-PCR were compared. RESULT: Total 405 samples were collected, of which 250 males and 155 females. In the 391 samples included for analysis, 370 (94.63%) samples were found to have concordance results, and 21 (5.37%) samples had discordant results. CONCLUSION: The use of saliva to diagnose COVID 19 infection is reliable, and its use can be recommended.

Fatty acid oxidation fuels agonist-induced platelet activation and thrombus formation: Targeting ß-oxidation of fatty acids as an effective anti-platelet strategy.

Platelet mitochondria possess remarkable plasticity for oxidation of energy substrates, where metabolic dependency on glucose or fatty acids is higher than glutamine. Since platelets metabolize nearly the entire pool of glucose to lactate rather than fluxing through mitochondrial tricarboxylic acid cycle, we posit that majority of mitochondrial ATP, which is essential for platelet granule secretion and thrombus formation, is sourced from oxidation of fatty acids. We performed a comprehensive analysis of bioenergetics and function of stimulated platelets in the presence of etomoxir, trimetazidine and oxfenicine, three pharmacologically distinct inhibitors of ß-oxidation. Each of them significantly impaired oxidative phosphorylation in unstimulated as well as thrombin-stimulated platelets leading to a small but consistent drop in ATP level in activated cells due to a lack of compensation from glycolytic ATP. Trimetazidine and oxfenicine attenuated platelet aggregation, P-selectin externalization and integrin αIIb ß3 activation. Both etomoxir and trimetazidine impeded agonist-induced dense granule release and platelet thrombus formation on collagen under arterial shear. The effect of inhibitors on platelet aggregation and dense granule release was dose- and incubation time- dependent with significant inhibition at higher doses and prolonged incubation times. Neither of the inhibitors could protect mice from collagen-epinephrine-induced pulmonary embolism or prolong mouse tail bleeding times. However, mice pre-administered with etomoxir, trimetazidine and oxfenicine were protected from ferric chloride-induced mesenteric thrombosis. In conclusion, ß-oxidation of fatty acids sustains ATP level in stimulated platelets and is therefore essential for energy-intensive agonist-induced platelet responses. Thus, fatty acid oxidation may constitute an attractive therapeutic target for novel antiplatelet agents.

Doença coronariana em jovens: novas formas de detecção, prevenção e tratamento / Coronary heart disease in young individuals: novel ways to detect, prevent and treat

Apesar dos grandes avanços nas estratégias de manejo e prevenção da aterosclerose, a prevalência da doença arterial coronariana aumenta em todo o mundo, tendo início em idade precoce. As doenças cardiovasculares em adultos jovens caracterizam-se como um grupo heterogêneo de doenças que ocorrem por causas congênitas ou adquiridas. Múltiplos fatores de risco, como dislipidemia, doença coronária prematura, diabetes melito e tabagismo, potencializam o risco do paciente para a coronariopatia precoce. A avaliação precoce de pacientes com doença arterial coronariana pode ser feita por meio de vários métodos de imagem não invasivos, que facilitam a seleção precoce de condutas preventivas e terapêuticas efetivas para manejo da doença arterial coronariana; no entanto, ela está associada a várias dificuldades, devido às limitações dos escores de risco e à sensibilidade limitada de vários métodos de rastreamento. Neste manuscrito, discutimos sobre fisiopatologia, fatores de risco, métodos de imagem invasivos e não invasivos e várias estratégias de manejo na prevenção precoce da doença coronariana em adultos jovens e, mais importante, os rumos futuros e a prevenção de doenças e da morte súbita cardíaca.

In spite of major advancements in the management and prevention strategies of atherosclerosis, the prevalence of coronary artery disease has risen worldwide, and might start at an early age. Cardiovascular diseases among young adults are characterized as a heterogeneous group of disorders due to congenital or acquired causes. Multiple risk factors, such as dyslipidemia, premature coronary heart disease, diabetes mellitus and cigarette smoking potentiate the patient's risk for early coronary heart disease. Early assessment of patients with coronary artery disease can be performed using various non-invasive imaging methods, which facilitate early selection of effective and preventative therapies for coronary artery disease management; however, it is associated with several challenges due to limitations in risk calculators, and limited sensitivity of various screening methods. In this manuscript, we will discuss about pathophysiology, risk factors, invasive and non- invasive imaging methods, and various management strategies for the early prevention of coronary heart disease in young adults and, importantly, the future directions and preventing disease and sudden cardiac death.