Pro-Inflammatory Effects of Platelet Transfusions in Newborn Mice with and without Underlying Inflammation

Platelet transfusions (PTx) are frequently given to thrombocytopenic preterm neonates at higher platelet count (PC) thresholds than those used in adults, in an attempt to reduce their bleeding risk. However, in the largest randomized trial of neonatal PTx thresholds, infants transfused at a higher PC threshold had a significantly higher mortality and/or major bleeding compared to infants transfused at a lower threshold. Since platelets carry multiple cytokines and chemokines, and since activated adult platelets may have a higher ability to interact with immune cells than neonatal platelets (due to their higher P-selectin expression levels), we hypothesized that the deleterious effects of PTx in neonates would be related to pro-inflammatory effects. We further hypothesized that the effects of PTx on the systemic inflammatory response would be different in thrombocytopenic neonates with non-inflammatory conditions (e.g., intrauterine growth restriction, drugs, genetic syndromes) compared to neonates with underlying inflammation (e.g., sepsis, necrotizing enterocolitis). To test the effects of PTx in the absence of inflammation, we transfused healthy post-natal day 10 (P10) C57BL/6 pups with washed platelets (5x10 7/g, isolated from adult C57BL/6J mice or eGFP+ mice) or with Tyrode's buffer (TY control). Blood was collected via terminal bleed 2h, 4h, and 6h after transfusion, and plasma was separated for quantification of 31 pro- and anti-inflammatory cytokines by multiplex (n=5-10 mice per group/timepoint). Two hours after PTx, the transfused mice exhibited significantly higher levels of G-CSF, IL-1, IL-1, IL-6, IL-17, KC (CXCL1) and MCP-1 compared to controls, with the most striking increases observed in IL-6 (928±19 vs. 135±36 pg/dL, p<0.001) and KC (1201±239 vs 371±77 pg/dL, p=0.001). At 4h post-transfusion, the levels of most cytokines were decreasing, with the exception of G-CSF (1940±276 vs. 825±126 pg/dL, p=0.003), MCP-1 (185±39 vs. 58±14 pg/dL, p=0.003), and IL-17 (2.12±1 vs. 0.66±0.3 pg/dL, p=0.002), which peaked at four hours. All cytokines were decreasing by 6h. Next, to model neonates with inflammatory conditions, we injected P10 pups with lipopolysaccharide (LPS) IP at a sub-lethal dose (1µg/g), which induced mild weight loss, thrombocytopenia (~ 50% drop in PC), and leukopenia followed by leukocytosis. Two hours after LPS injection, pups were transfused with washed platelets from adult C57BL/6 mice or TY (as above). Blood was obtained by terminal phlebotomy 4h, 8h or 18h post LPS injection and plasma was separated and stored for cytokine quantification by multiplex. 4h after LPS, PTx pups had significantly higher levels of leukemia inhibitory factor (LIF, a member of the IL-6 family) compared to TY controls (35±6 pg/mL vs. 17±3.9 pg/mL, p<0.01). At both 4 and 8h, IL-6 and G-CSF levels were extremely high and at or above the upper limit of the standard curve in both groups. By 18h post-LPS, the majority of cytokines had decreased to near-normal levels in TY control pups, while IL-6, IL-5, KC (CXCL1) and IL-10 remained significantly elevated in PTx mice (IL-6: 601±114 vs. 187±38 pg/mL, p=0.0007; IL-5: 659±257 vs. 486±191 pg/mL, p=0.01; KC: 4569±1370 vs. 2686±827 pg/mL, p=0.04; IL-10: 729±283 vs. 330±131 pg/mL, p=0.009). Since IL-10 is an anti-inflammatory cytokine, we also evaluated the relation of IL-6 to IL-10 in PTx vs. TY control mice. This analysis showed that IL-6 levels were 2.3 times higher for any given IL-10 level in pups who received PTx compared to controls. In conclusion, our findings suggest that platelet transfusions induce an inflammatory response in newborn mice without underlying inflammation, characterized mostly by elevations in IL-6, G-CSF and KC. In newborn pups with underlying sub-lethal inflammation, platelet transfusions seem to prolong the inflammatory response. These observations may provide an explanation for the increased morbidity and mortality in human neonates receiving liberal PTx. Studies to identify the mechanisms through which platelets induce these responses are ongoing. Disclosures No relevant conflicts of interest to declare.

Influence of the Microbiome on Chronic Rhinosinusitis With and Without Polyps: An Evolving Discussion

Chronic rhinosinusitis (CRS) is widely prevalent within the population and often leads to decreased quality of life, among other related health complications. CRS has classically been stratified by the presence of nasal polyps (CRSwNP) or the absence nasal polyps (CRSsNP). Management of these conditions remains a challenge as investigators continue to uncover potential etiologies and therapeutic targets. Recently, attention has been given to the sinunasal microbiota as both an inciting and protective influence of CRS development. The healthy sinunasal microbiologic environment is largely composed of bacteria, with the most frequent strains including Staphylococcus aureus, Streptococcus epidermidis, and Corynebacterium genera. Disruptions in this milieu, particularly increases in S. aureus concentration, have been hypothesized to perpetuate both Th1 and Th2 inflammatory changes within the nasal mucosa, leading to CRS exacerbation and potential polyp formation. Other contributors to the sinunasal microbiota include fungi, viruses, and bacteriophages which may directly contribute to underlying inflammation or impact bacterial prevalence. Modifiable risk factors, such as smoking, have also been linked to microbiota alterations. Research interest in CRS continues to expand, and thus the goal of this review is to provide clinicians and investigators alike with a current discussion on the microbiologic influence on CRS development, particularly with respect to the expression of various phenotypes. Although this subject is rapidly evolving, a greater understanding of these potential factors may lead to novel research and targeted therapies for this often difficult to treat condition.

How Inflammation Pathways Contribute to Cell Death in Neuro-Muscular Disorders

Neuro-muscular disorders include a variety of diseases induced by genetic mutations resulting in muscle weakness and waste, swallowing and breathing difficulties. However, muscle alterations and nerve depletions involve specific molecular and cellular mechanisms which lead to the loss of motor-nerve or skeletal-muscle function, often due to an excessive cell death. Morphological and molecular studies demonstrated that a high number of these disorders seem characterized by an upregulated apoptosis which significantly contributes to the pathology. Cell death involvement is the consequence of some cellular processes that occur during diseases, including mitochondrial dysfunction, protein aggregation, free radical generation, excitotoxicity and inflammation. The latter represents an important mediator of disease progression, which, in the central nervous system, is known as neuroinflammation, characterized by reactive microglia and astroglia, as well the infiltration of peripheral monocytes and lymphocytes. Some of the mechanisms underlying inflammation have been linked to reactive oxygen species accumulation, which trigger mitochondrial genomic and respiratory chain instability, autophagy impairment and finally neuron or muscle cell death. This review discusses the main inflammatory pathways contributing to cell death in neuro-muscular disorders by highlighting the main mechanisms, the knowledge of which appears essential in developing therapeutic strategies to prevent the consequent neuron loss and muscle wasting.

Prevalence, etiologies and complications of teeth hypomineralization in pediatrics

Dental hypomineralization represents a major problem in childhood health that can cause serious problems and may even affect the permanent dentition. In previous literature review, the term molar incisor hypomineralization (MIH) has been frequently reported among different studies. However, the clinical problems and complications of the condition are not commonly described among studies in the literature, which adds a value to this current study. The present study was a literature review that aimed to discuss the problems of hypomineralization in baby teeth and the reported common problems according to recent studies in the literature. Tooth loss, anesthetic problems within the anterior teeth, hypersensitivity and the presence of underlying inflammation are potential complications that might affect these patients. Moreover, it was also previously reported that the subsurfaces of the affected enamels are usually porous and soft. On other hand, the surfaces of the intact enamels are usually hypermineralized, hard and smooth, owing to the subsequent post-eruptive maturation. Identification of the underlying etiology and risk factors is important for the proper management of these cases. A systemic origin of the disorder was strongly suggested while other environmental and genetic factors had been suggested. Moreover, establishing a proper diagnosis can be hard due to the presence of some similar disorders. Therefore, a differential diagnosis should be established as it is discussed in this literature.

Cardiovascular Risk in Rheumatoid Arthritis: Literature Review

Rheumatoid arthritis (RA) is the most common inflammatory arthritis disease with a worldwide prevalence of 1–3%. RA patients are at higher risk of atherosclerosis than their matched age-sex controls. Cardiovascular diseases (CVDs) account for a 50% risk of increased mortality and morbidity in RA. The pattern of CVD in RA patients differs from that in the general population; RA patients are more likely to have silent ischemic heart disease, sudden death, heart failure, and die early. RA patients tend to have a 5–10 years reduction in their life span than their matched healthy population. Traditional (classical) CV risk factors work separately or synergistically with the underlying inflammation to increase CVD risk in RA. Moreover, inflammation is defined as an independent CVD risk factor. This literature review aims to discuss the traditional CVD risk factors and their association with inflammation in RA.

Oxy-hydrogen Gas: The Rationale Behind Its Use as a Novel and Sustainable Treatment for COVID-19 and Other Respiratory Diseases

Oxy-hydrogen gas (HHO) is a gaseous mixture of molecular hydrogen and molecular oxygen that is generated by the electrolysis of water and delivered in a 2:1 ratio (66% and 33%, respectively) through the use of noninvasive inhalation devices such as nasal cannulas or nebulisers. Although there is a paucity of scientific evidence supporting this new and emerging therapy, initial investigations indicate that HHO proffers cytoprotective qualities, typically by reducing oxidative stress and attenuating the inflammatory response. These aspects are particularly favourable when considering respiratory medicine because underlying inflammation is known to drive the pathological progress of numerous respiratory conditions, including asthma, chronic obstructive pulmonary disorder, and, pertinently, coronavirus disease (COVID-19). Direct delivery to the lung parenchyma is also likely to increase the effectiveness of this emerging medical therapy. This narrative review aims to delineate how this particular combination of gases can affect cellular processes at the molecular level by focussing on the evolutionary requirement for both oxygen and hydrogen. Furthermore, the authors assess the current available data for the safety and efficacy of HHO in a clinical setting.

Prevalence of overuse of short-acting beta-2 agonists (SABA) and associated factors among patients with asthma in Germany

Background Overuse of short-acting beta-2 agonists (SABA), which do not treat the underlying inflammation of asthma, is linked to poor clinical outcomes such as increased exacerbation risk. This study, as part of the SABINA program, estimated the prevalence of SABA overuse and associated variables in outpatients in Germany. Methods This retrospective study used anonymized electronic healthcare data from the Disease Analyzer database (IQVIA). A total of 15,640 patients aged ≥ 12 years with asthma who received ≥ 1 SABA prescription(s) between July 2017 and June 2018 in 924 general physician and 22 pneumologist (PN) practices were included. SABA overuse was defined as ≥ 3 prescribed inhalers (~ 200 puffs each) during the study period. The associations between SABA overuse and physician specialty, Global Initiative for Asthma (GINA) steps (based on asthma medications), age, sex, and inhaled corticosteroid (ICS)/long-acting beta agonist (LABA) use were estimated using multivariable regression for patients with probable moderate (GINA step 2) and probable severe (GINA steps 3–5) asthma. Results Annually, 36% of all patients (GINA steps 1–5) in general and 38% in PN practices received ≥ 3 SABA inhalers. The risk of SABA overuse was 14% higher in patients treated by a general practitioner vs. a PN; 34% and 85% higher in GINA steps 4 and 5, respectively, vs. GINA step 3; and 40% higher in male vs. female patients. Conclusions SABA overuse is prevalent among patients with asthma across all GINA steps in Germany, which may indicate suboptimal asthma control. Further studies are needed to investigate the reasons behind SABA overuse.

A Narrative Review of the Classification and Use of Diagnostic Ultrasound for Conditions of the Achilles Tendon

Enthesitis is a cardinal feature of spondyloarthropathies. The Achilles insertion on the calcaneus is a commonly evaluated enthesis located at the hindfoot, generally resulting in hindfoot pain and possible tendon enlargement. For decades, diagnosis of enthesitis was based upon patient history of hindfoot or posterior ankle pain and clinical examination revealing tenderness and/or enlargement at the site of the tendon insertion. However, not all hindfoot or posterior ankle symptoms are related to enthesitis. Advanced imaging, including magnetic resonance imaging (MRI) and ultrasound (US), has allowed for more precise evaluation of hindfoot and posterior ankle conditions. Use of US in diagnosis has helped confirm some of these cases but also identified other conditions that may have otherwise been misclassified without use of advanced imaging diagnostics. Conditions that may result in hindfoot and posterior ankle symptoms related to the Achilles tendon include enthesitis (which can include retrocalcaneal bursitis and insertional tendonopathy), midportion tendonopathy, paratenonopathy, superficial calcaneal bursitis, calcaneal ossification (Haglund deformity), and calcific tendonopathy. With regard to classification of these conditions, much of the existing literature uses confusing nomenclature to describe conditions in this region of the body. Some terminology may imply inflammation when in fact there may be none. A more uniform approach to classifying these conditions based off anatomic location, symptoms, clinical findings, and histopathology is needed. There has been much debate regarding appropriate use of tendonitis when there is no true inflammation, calling instead for use of the terms tendinosis or tendonopathy. To date, there has not been clear examination of a similar overuse of the term enthesitis in conditions where there is no underlying inflammation, thus raising the need for more comprehensive taxonomy.