What Function Do Platelets Play in Inflammation and Bacterial and Viral Infections?

Friend or foe: the role of platelets in acute lung injury

Lung diseases, including acute lung injury (ALI) and acute respiratory distress syndrome (ARDS), are associated with various etiological factors and are characterized by high mortality rates. Current treatment strategies primarily focus on lung-protective ventilation and careful fluid management. Despite over 50 years of basic and clinical research, effective treatment options remain limited, and the search for novel strategies continues. Traditionally, platelets have been viewed primarily as contributors to blood coagulation; however, recent research has revealed their significant role in inflammation and immune regulation. While the relationship between platelet count and ALI/ARDS has remained unclear, emerging studies highlight the "dual role" of platelets in these conditions. On one hand, platelets interact with neutrophils to form neutrophil extracellular traps (NETs), promoting immune thrombosis and exacerbating lung inflammation. On the other hand, platelets also play a protective role by modulating inflammation, promoting regulatory T cell (Treg) activity, and assisting in alveolar macrophage reprogramming. This dual functionality of platelets has important implications for the pathogenesis and resolution of ALI/ARDS. This review examines the multifaceted roles of platelets in ALI/ARDS, focusing on their immunomodulatory effects, the platelet-neutrophil interaction, and the critical involvement of platelet-Treg cell complexes in shaping the inflammatory environment in ALI.

Fucosylated Glycosaminoglycan Oligosaccharide HS14, Derived from Sea Cucumbers, Is a Novel Inhibitor of Platelet Toll-like Receptor 2

(1) Background: Toll-like receptor 2 (TLR2) on platelets is increasingly recognized as a pivotal mediator in infection-induced platelet activation and aggregation, contributing to both inflammatory and thrombotic diseases. Targeting TLR2 on platelets offers a promising therapeutic strategy for inflammatory and thrombotic-related disorders. However, inhibitors targeting platelet TLR2 have not yet been reported. (2) Methods: Platelet aggregation was assessed using a light transmission aggregometer. Platelet activation was evaluated by measuring the release of P-selectin and von Willebrand factor (vWF) via ELISA. Intracellular Ca2+ mobilization was quantified using Fluo 3-AM fluorescence, recorded by flow cytometry. Static platelet adhesion was visualized under a microscope, and the formation of platelet-granulocyte aggregates in human whole blood was analyzed by flow cytometry. (3) Results: Fucosylated glycosaminoglycan (FG) tetradecasaccharide HS14 inhibited the activation and aggregation of human platelets induced by the synthetic bacterial lipopeptide Pam3CSK4 in a concentration-dependent manner. This inhibitory effect gives rise to significant anti-inflammatory and anti-thrombotic activities, as evidenced by reduced platelet adhesion and decreased platelet-granulocyte aggregates formation in human whole blood. (4) Conclusions: This study is the first to identify FG oligosaccharide HS14 as a promising inhibitor of platelet TLR2/TLR1, demonstrating significant therapeutic potential for inflammatory and thrombotic-related diseases.

Systemic immune-inflammation index and long-term mortality in patients with hypertension: a cohort study

OBJECTIVE

The objective of this study was to examine the relationship between systemic inflammation and long-term mortality in patients with hypertension.

METHODS

The study employed a retrospective cohort design. The study population was derived from the National Health and Nutrition Examination Survey (NHANES), and the mortality data for this population was acquired from the National Death Index (NDI) database. Systemic inflammation was quantified by the Systemic Immune Inflammation Index (SII) and the Systemic Inflammatory Response Index (SIRI), which were then categorized into four groups (Q1-Q4, with Q4 representing the highest level of SII or SIRI). Weighted Cox regression models were constructed to investigate the association between mortality and SII and SIRI, with hazard ratios (HRs) subsequently calculated.

RESULTS

A total of 7431 participants were included in the analysis. The highest quantile (Q4) of SII was associated with a higher risk of all-cause mortality (hazard ratio 1.36, 95% CI 1.1-1.69, P  < 0.001). After adjustment for important covariates, the association remained significant (hazard ratio 1.70, 95% CI 1.27-2.30, P  < 0.001). The highest quantile (Q4) of SIRI was also associated with the highest risk of mortality (hazard ratio 2.11, 95% CI 1.64-2.70, P  < 0.001), and this association remained significant after adjustment for important covariates (hazard ratio 1.64, 95% CI 0.61-1.22, P  = 0.001).

CONCLUSION

Both SII and SIRI scores were found to be associated with mortality rates in patients with hypertension. The findings suggest that these scores may serve as complementary biomarkers to the neutrophil-to-lymphocyte ratio (NLR) for assessing mortality risk in patients with hypertension. Further investigation is warranted to elucidate the underlying mechanisms that underpin this association.

PROTACs in platelets: emerging antithrombotic strategies and future perspectives

PURPOSE OF REVIEW

Proteolysis-targeted chimeras (PROTACs) are heterobifunctional compounds that selectively target proteins for degradation and are an emerging therapeutic modality to treat diseases such as cancer and neurodegenerative disorders. This review will widen the area of application by highlighting the ability of PROTACs to remove proteins from the anucleate platelets and evaluate their antithrombotic potential.

RECENT FINDINGS

Proteomic and biochemical studies demonstrated that human platelets possess the Ubiquitin Proteasomal System as well as the E3 ligase cereblon (CRBN) and therefore may be susceptible to PROTAC-mediated protein degradation. Recent findings confirmed that CRBN ligand-based PROTACs targeting generic tyrosine kinases, Btk and/or Fak lead to efficacious and selective protein degradation in human platelets. Downregulation of Btk, a key player involved in signalling to thrombosis, but not haemostasis, resulted in impaired in-vitro thrombus formation.

SUMMARY

Platelets are susceptible to targeted protein degradation by CRBN ligand-based PROTACs and have limited ability to resynthesise proteins, ensuring long-term downregulation of target proteins. Therefore, PROTACs serve as an additional research tool to study platelet function and offer new therapeutic potential to prevent thrombosis. Future studies should focus on enhancing cell specificity to avoid on-target side effects on other blood cells.

Characterization of Platelet Receptors and Their Involvement in Immune Activation of These Cells

The article characterises platelets, pointing out the role and contribution of their numerous receptors determining their specific and broad immune activity. Three types of platelet receptors are described, that is, extracellular and intracellular receptors-TLR (toll-like receptors), NLR (NOD-like receptor), and RLR (RIG-I-like receptor); extracellular receptors-selectins and integrins; and their other extracellular receptors-CLR (C-type lectin receptor), CD (cluster of differentiation), TNF (tumour necrosis factor), among others. Outlining the contribution of these numerous platelet receptors to the intravascular immunity, it has been shown that they are formed by their fusion with pathogen-associated molecular patterns (PAMPs), damage-associated molecular patterns (DAMPs), and lifestyle-associated molecular patterns (LAMPs). They are initiating and effector components of signal transduction of these cells, and their expression and quantity determine the specific and broad functions of platelets towards influencing vascular endothelial cells, but mainly PRRs (pattern recognition receptors) of blood immune cells. These facts make platelets the fundamental elements that shape not only intravascular homeostasis, as previously indicated, but they become the determinants of immunity in blood vessels. Describing the reactions of the characterised three groups of platelet receptors with PAMP, DAMP and LAMP molecules, the pathways and participation of platelets in the formation and construction of intravascular immune status, in physiological states, but mainly in pathological states, including bacterial and viral infections, are presented, making these cells essential elements in the health and disease of mammals, including humans.

Inpatient outcomes of NSTEMI among patients with immune thrombocytopenia: a propensity matched national study

Patients with immune thrombocytopenia (ITP) admitted for non-ST elevation myocardial infarction (NSTEMI) present a unique therapeutic challenge due to the increased risk of bleeding with antiplatelet and anticoagulation therapies. There is limited evidence studying hospital mortality and complications in this population. The study included a patient cohort from the 2018-2021 National Inpatient Sample database. Propensity score matched NSTEMI patients with and without ITP using a 1:1 matching ratio. Outcomes analyzed were in-hospital mortality, rates of diagnostic angiogram, percutaneous coronary intervention (PCI), acute kidney injury (AKI), congestive heart failure (CHF), cardiogenic shock, cardiac arrest, mechanical ventilation, tracheal intubation, ventricular tachycardia (VT), ventricular fibrillation (VF), major bleeding, need for blood and platelet transfusion, length of stay (LOS), and total hospitalization charges. A total of 1,699,020 patients met inclusion criteria (660,490 females [39%], predominantly Caucasian 1,198,415 (70.5%); mean [SD] age 67, [3.1], including 2,615 (0.1%) patients with ITP. Following the propensity matching, 1,020 NSTEMI patients with and without ITP were matched. ITP patients had higher rates of inpatient mortality (aOR 1.98, 95% CI 1.11-3.50, p 0.02), cardiogenic shock, AKI, mechanical ventilation, tracheal intubation, red blood cells and platelet transfusions, longer LOS, and higher total hospitalization charges. The rates of diagnostic angiogram, PCI, CHF, VT, VF, and major bleeding were not different between the two groups. Patients with ITP demonstrated higher odds of in-hospital mortality for NSTEMI and need for platelet transfusion with no difference in rates of diagnostic angiogram or PCI.

New vaccination approach using formalin-killed Streptococcus pyogenes vaccine on the liver of Oreochromis niloticus fingerlings

Newly synthesized vaccines prepared from formalin-killed bacteria Streptococcus pyogenes were investigated in the current study to evaluate the effectiveness of the newly synthesized vaccine as well as their safety by injected intraperitoneal. The study involved several steps 1st step is the preparation of the vaccine followed by the 2nd step: Evaluate the effectiveness and vaccine safety against pathogenic S. pyogenes through 4 different groups including control (Group I). Group II (Bacterial, infected group), Group III (Vaccine), and the Last group was the challenged group after the vaccination (Vacc + Bac). Different Immunological and biochemical parameters were measured in addition to hematological and histopathological examinations. For example, oxidative/antioxidants, inflammatory biomarkers, fragmentation and cell damage, and finally the histopathological study. The current study showed an increase in all oxidative, inflammatory, and cell damage (DNA fragmentation assays), additionally markedly elevation in histopathological cell damage in the infected group (Group II) compared with the control group. The vaccine and challenged after vaccination group (vaccine + Bacteria), showed great improvement in oxidative biomarkers (LPO) and an increase in antioxidants biomarkers (GSH, SOD, GST, DPPH, ABTS, GR and GPx), Also the inflammation and histopathological examination. The newly synthesized vaccine improved the resistance of Oreochromis niloticus and can be used as a preventive therapy agent for pathogenic bacteria S. pyogenes.

An Investigation of Mortality Associated With Comorbid Pneumonia and Thrombocytopenia in a Rural Southwest Missouri Hospital System

BACKGROUND

Pneumonia places a significant burden on individuals and society, contributing to a substantial number of hospital admissions, emergency department visits, deaths, and healthcare costs each year. Comorbidities can greatly increase the risk of poor outcomes when associated with pneumonia. One comorbidity that has yet to be thoroughly researched is thrombocytopenia, which is known to play an important role in activating the immune response to infections. A decrease in platelet count may limit the immune response and consequently increase mortality in patients with pneumonia. The purpose of this study was to investigate whether comorbid thrombocytopenia and pneumonia are associated with poor outcomes.

METHODS

This study was a retrospective cohort analysis comparing mortality rates among patients with comorbid thrombocytopenia and pneumonia, pneumonia without thrombocytopenia, and thrombocytopenia without pneumonia. Data were collected from Freeman Health System using International Classification of Diseases, Tenth Revision (ICD-10) codes from January 1, 2019, to December 31, 2021. ICD-10 codes for pneumonia and thrombocytopenia were extracted and stratified into three groups: those with both pneumonia and thrombocytopenia, those with pneumonia without thrombocytopenia, and those with thrombocytopenia without pneumonia. Mortality rates were then compared across the three groups.

RESULTS

There were 4,414 patients admitted with pneumonia and 1,157 admissions for thrombocytopenia without pneumonia. Among the 4,414 patients admitted with pneumonia, 3,902 did not have thrombocytopenia, while 512 had thrombocytopenia. Of the patients without thrombocytopenia, 14% (3,902) expired. Among the 512 patients with thrombocytopenia, 43% expired. In the thrombocytopenia without pneumonia group, 11% (1,157) expired.

CONCLUSION

These results indicate a significant increase in mortality in patients with both pneumonia and thrombocytopenia compared to those with pneumonia without thrombocytopenia (an increase in mortality of 28.93% with a 95% CI: 24.50-33.36%, P < 0.0001). While pneumonia itself increases mortality compared to the general population, patients with both pneumonia and thrombocytopenia exhibit even higher mortality rates.

Supernatant of platelet-Klebsiella pneumoniae coculture induces apoptosis-like death in Klebsiella pneumoniae

Multidrug-resistant Klebsiella pneumoniae strains, especially carbapenem-resistant K. pneumoniae, have become a rapidly emerging crisis worldwide, greatly limiting current therapeutic options and posing new challenges to infection management. Therefore, it is imperative to develop novel and effective biological agents for the treatment of multidrug-resistant K. pneumoniae infections. Platelets play an important role in the development of inflammation and immune responses. The main component responsible for platelet antibacterial activity lies in the supernatant stimulated by gram-positive bacteria. However, little research has been conducted on the interaction of gram-negative bacteria with platelets. Therefore, we aimed to explore the bacteriostatic effect of the supernatant derived from platelet-K. pneumoniae coculture and the mechanism underlying this effect to further assess the potential of platelet-bacterial coculture supernatant. We conducted this study on the gram-negative bacteria K. pneumoniae and CRKP and detected turbidity changes in K. pneumoniae and CRKP cultures when grown with platelet-K. pneumoniae coculture supernatant added to the culture medium. We found that platelet-K. pneumoniae coculture supernatant significantly inhibited the growth of K. pneumoniae and CRKP in vitro. Furthermore, transfusion of platelet-K. pneumoniae coculture supernatant alleviated the symptoms of K. pneumoniae and CRKP infection in a murine model. Additionally, we observed apoptosis-like changes, such as phosphatidylserine exposure, chromosome condensation, DNA fragmentation, and overproduction of reactive oxygen species in K. pneumoniae following treatment with the supernatant. Our study demonstrates that the platelet-K. pneumoniae coculture supernatant can inhibit K. pneumoniae growth by inducing an apoptosis-like death, which is important for the antibacterial strategies development in the future.IMPORTANCEWith the widespread use of antibiotics, bacterial resistance is increasing, and a variety of multi-drug resistant Gram-negative bacteria have emerged, which brings great challenges to the treatment of infections caused by Gram-negative bacteria. Therefore, finding new strategies to inhibit Gram-negative bacteria and even multi-drug- resistant Gram-negative bacteria is crucial for treating infections caused by Gram-negative bacteria, improving the abuse of antibiotics, and maintaining the balance between bacteria and antibiotics. K. pneumoniae is a common clinical pathogen, and drug-resistant CRKP is increasingly difficult to cure, which brings great clinical challenges. In this study, we found that the platelet-K. pneumoniae coculture supernatant can inhibit K. pneumoniae growth by inducing an apoptosis-like death. This finding has inspired the development of future antimicrobial strategies, which are expected to improve the clinical treatment of Gram-negative bacteria and control the development of multidrug-resistant strains.

Megakaryocytes possess a STING pathway that is transferred to platelets to potentiate activation

Platelets display unexpected roles in immune and coagulation responses. Emerging evidence suggests that STING is implicated in hypercoagulation. STING is an adaptor protein downstream of the DNA sensor cyclic GMP-AMP synthase (cGAS) that is activated by cytosolic microbial and self-DNA during infections, and in the context of loss of cellular integrity, to instigate the production of type-I IFN and pro-inflammatory cytokines. To date, whether the cGAS-STING pathway is present in platelets and contributes to platelet functions is not defined. Using a combination of pharmacological and genetic approaches, we demonstrate here that megakaryocytes and platelets possess a functional cGAS-STING pathway. Our results suggest that in megakaryocytes, STING stimulation activates a type-I IFN response, and during thrombopoiesis, cGAS and STING are transferred to proplatelets. Finally, we show that both murine and human platelets contain cGAS and STING proteins, and the cGAS-STING pathway contributes to potentiation of platelet activation and aggregation. Taken together, these observations establish for the first time a novel role of the cGAS-STING DNA sensing axis in the megakaryocyte and platelet lineage.

Platelet-Derived Extracellular Vesicles as Lipid Carriers in Severe Allergic Inflammation

The resolution of inflammation is a complex process that is critical for removing inflammatory cells and restoring tissue function. The dysregulation of these mechanisms leads to chronic inflammatory disorders. Platelets, essential cells for preserving homeostasis, are thought to play a role in inflammation as they are a source of immunomodulatory factors. Our aim was to identify key metabolites carried by platelet-derived extracellular vesicles (PL-EVs) in a model of allergic inflammation. PL-EVs were isolated by serial ultracentrifugation using platelet-rich plasma samples obtained from platelet apheresis from severely (n = 6) and mildly (n = 6) allergic patients and non-allergic individuals used as controls (n = 8). PL-EVs were analysed by a multiplatform approach using liquid and gas chromatography coupled to mass spectrometry (LC-MS and GC-MS, respectively). PL-EVs obtained from severely and mildly allergic patients and control individuals presented comparable particle concentrations and sizes with similar protein concentrations. Strikingly, PL-EVs differed in their lipid and metabolic content according to the severity of inflammation. L-carnitine, ceramide (Cer (d18:0/24:0)), and several triglycerides, all of which seem to be involved in apoptosis and regulatory T functions, were higher in PL-EVs from patients with mild allergic inflammation than in those with severe inflammation. In contrast, PL-EVs obtained from patients with severe allergic inflammation showed an alteration in the arachidonic acid pathway. This study demonstrates that PL-EVs carry specific lipids and metabolites according to the degree of inflammation in allergic patients and propose novel perspectives for characterising the progression of allergic inflammation.

Platelet Metabolic Flexibility: A Matter of Substrate and Location

Platelets are cellular elements that are physiologically involved in hemostasis, inflammation, thrombotic events, and various human diseases. There is a link between the activation of platelets and their metabolism. Platelets possess considerable metabolic versatility. Although the role of platelets in hemostasis and inflammation is known, our current understanding of platelet metabolism in terms of substrate preference is limited. Platelet activation triggers an oxidative metabolism increase to sustain energy requirements better than aerobic glycolysis alone. In addition, platelets possess extra-mitochondrial oxidative phosphorylation, which could be one of the sources of chemical energy required for platelet activation. This review aims to provide an overview of flexible platelet metabolism, focusing on the role of metabolic compartmentalization in substrate preference, since the metabolic flexibility of stimulated platelets could depend on subcellular localization and functional timing. Thus, developing a detailed understanding of the link between platelet activation and metabolic changes is crucial for improving human health.

Gestational psittacosis causes severe pneumonia and miscarriage: A case report and literature review

Psittacosis is an uncommon zoonotic illness, and gestational psittacosis is even rarer. The clinical signs and symptoms of psittacosis are varied, often overlooked, and swiftly identified by metagenomic next-generation sequencing. We recorded the case of a 41-year-old pregnant woman with psittacosis where the disease was not detected early on, resulting in severe pneumonia and fetal miscarriage. The clinical symptoms, diagnosis, and treatment of psittacosis in pregnancy are the subject of this case study.

The Role of Platelets in Infective Endocarditis

Over the last decade, the incidence of infective endocarditis (IE) has increased, with a change in the frequency of causative bacteria. Early evidence has substantially demonstrated the crucial role of bacterial interaction with human platelets, with no clear mechanistic characterization in the pathogenesis of IE. The pathogenesis of endocarditis is so complex and atypical that it is still unclear how and why certain bacterial species will induce the formation of vegetation. In this review, we will analyze the key role of platelets in the physiopathology of endocarditis and in the formation of vegetation, depending on the bacterial species. We provide a comprehensive outline of the involvement of platelets in the host immune response, investigate the latest developments in platelet therapy, and discuss prospective research avenues for solving the mechanistic enigma of bacteria-platelet interaction for preventive and curative medicine.

Protocols for the Isolation of Platelets for Research and Contrast to Production of Platelet Concentrates for Transfusion

Platelets are specialized cellular elements of blood and play a central role in maintaining normal hemostasis, wound healing, and host defense but also are implicated in pathologic processes of thrombosis, inflammation, and tumor progression and dissemination. Transfusion of platelet concentrates is an important treatment for thrombocytopenia (low platelet count) due to disease or significant blood loss, with the goal being to prevent bleeding or to arrest active bleeding. In blood circulation, platelets are in a resting state; however, when triggered by a stimulus, such as blood vessel injury, become activated (also termed procoagulant). Platelet activation is the basis of their biological function to arrest active bleeding, comprising a complex interplay of morphological phenotype/shape change, adhesion, expression of signaling molecules, and release of bioactive factors, including extracellular vesicles/microparticles. Advances in high-throughput mRNA and protein profiling techniques have brought new understanding of platelet biological functions, including identification of novel platelet proteins and secreted molecules, analysis of functional changes between normal and pathologic states, and determining the effects of processing and storage on platelet concentrates for transfusion. However, because platelets are very easily activated, it is important to understand the different in vitro methods for platelet isolation commonly used and how they differ from the perspective for use as research samples in clinical chemistry. Two simple methods are described here for the preparation of research-scale platelet samples from human whole blood, and detailed notes are provided about the methods used for the preparation of platelet concentrates for transfusion.

Risk factors for diabetic foot ulcers mortality and novel negative pressure combined with platelet-rich plasma therapy in the treatment of diabetic foot ulcers

The purpose of this study was to assess the risk factors for morbidity and mortality of diabetic foot ulcers (DFUs). For the treatment of diabetic foot ulcers, negative pressure wound therapy (NPWT) combined with platelet-rich plasma-fibrin glue (PRP) was also investigated. There were 653 patients in the diabetic foot ulcer group and 510 patients in the diabetic patients without foot ulceration (NFU) group, for a total of 1163 patients in the study samples after individuals without follow-up were excluded. The patients were randomized into two groups: the negative pressure wound therapy group and the negative pressure wound therapy combined with the PRP group. The findings of the univariate analysis revealed the blood indicators for predicting diabetic foot ulcer morbidity risk factors, such as C-reactive protein, albumin, creatinine, alkaline phosphatase, procalcitonin, platelets, 25-hydroxyvitamin D, β-2-microglobulin, monocyte ratio, low-density protein cholesterol (LDL), triglyceride, alanine aminotransferase (ALT), aminotransferase (AST), creatine kinase (CK) and total cholesterol. Using logistic regression analysis revealed only albumin and age to be independent predictors of diabetic foot ulcer mortality. Our study also revealed that, compared to negative pressure wound therapy alone, negative pressure wound therapy combined with PRP accelerated wound healing and reduced the mortality rate. According to the findings of this pilot study, new risk factors for diabetic foot ulcer morbidity and mortality have been found, and negative pressure wound therapy combined with PRP therapy may provide the first information that it is an effective adjunct treatment for diabetic foot ulcers.

Effect of antiplatelet agents on Escherichia coli sepsis mechanisms: A review

Despite ever-increasing improvements in the prognosis of sepsis, this condition remains a frequent cause of hospitalization and mortality in Western countries. Sepsis exposes the patient to multiple complications, including thrombotic complications, due to the ability of circulating bacteria to activate platelets. One of the bacteria most frequently implicated in sepsis, Escherichia coli, a Gram-negative bacillus, has been described as being capable of inducing platelet activation during sepsis. However, to date, the mechanisms involved in this activation have not been clearly established, due to their multiple characteristics. Many signaling pathways are thought to be involved. At the same time, reports on the use of antiplatelet agents in sepsis to reduce platelet activation have been published, with variable results. To date, their use in sepsis remains controversial. The aim of this review is to summarize the currently available knowledge on the mechanisms of platelet activation secondary to Escherichia coli sepsis, as well as to provide an update on the effects of antiplatelet agents in these pathological circumstances.

Platelet-Derived Biomarkers: Potential Role in Early Pediatric Serious Bacterial Infection and Sepsis Diagnostics

Fever is the most common complaint of children who are attending a pediatric emergency department (PED). Most of the fever cases are of viral origin; however, the most common markers, such as leucocyte, neutrophil count, or C-reactive protein, are not sensitive or specific enough to distinguish the etiology of fever, especially if children present at the early phase of infection. Currently, platelets have been attributed a role as important sentinels in viral and bacterial infection pathogenesis. Thus, our aim was to analyze different platelet indices, such as PNLR (platelet-to-neutrophil/lymphocyte ratio), PNR (platelet-to-neutrophil ratio) as well as specific secreted proteins, such as sP-selectin, CXCL4, CXCL7, and serotonin. We included 68 children who were referred to PED with the early onset of fever (<12 h). All children with comorbidities, older than five years, and psychiatric diseases, who refused to participate were excluded. All the participants were divided into viral, bacterial, or serious bacterial infection (SBI) groups. All the children underwent blood sampling, and an additional sample was collected for protein analysis. Our analysis revealed statistically significant differences between leucocyte, neutrophil, and CRP levels between SBI and other groups. However, leucocyte and neutrophil counts were within the age norms. A higher PNLR value was observed in a bacterial group, PNR-in viral. As we tested CXCL7 and sP-selectin, alone and together those markers were statistically significant to discriminate SBI and sepsis from other causes of infection. Together with tachypnoe and SpO2 < 94%, it improved the prediction value of sepsis as well as SBI. CXCL4 and serotonin did not differ between the groups. Concluding, CXCL7 and sP-selectin showed promising results in early SBI and sepsis diagnosis.

Role of Platelets in Osteoarthritis-Updated Systematic Review and Meta-Analysis on the Role of Platelet-Rich Plasma in Osteoarthritis

Platelets are an essential component of hemostasis, with an increasing role in host inflammatory processes in injured tissues. The reaction between receptors and vascular endothelial cells results in the recruitment of platelets in the immune response pathway. The aim of the present review is to describe the role of platelets in osteoarthritis. Platelets induce secretion of biological substances, many of which are key players in the inflammatory response in osteoarthritis. Molecules involved in cartilage degeneration, or being markers of inflammation in osteoarthritis, are cytokines, such as tumor necrosis factor α (TNFα), interleukins (IL), type II collagen, aggrecan, and metalloproteinases. Surprisingly, platelets may also be used as a treatment modality for osteoarthritis. Multiple randomized controlled trials included in our systematic review and meta-analyses prove the effectiveness of platelet-rich plasma (PRP) as a minimally invasive method of pain alleviation in osteoarthritis treatment.