Fabrication and application of salicin-polycaprolactone 3D-printed scaffold in the healing of femur bone defects

Polycaprolactone (PCL) is a suitable material for bone repair due to good biocompatibility and mechanical properties. However, low bioactivity and hydrophobicity pose major challenges for its biomedical applications. To overcome these limitations, PCL-based scaffolds loaded with bioactive agents have been developed. Salicin (Sal) is an anti-inflammatory and analgesic herbal glycoside with osteogenic potential. In the present study, we aimed to produce a salicin-laden PCL (PCL-Sal) scaffold for bone healing applications. Three-dimensional (3D) scaffolds were produced and their biocompatibility, and physical-chemical characteristics were determined. The osteogenic potential of the net PCL (nPCL) and PCL-Sal scaffolds was evaluated using bone marrow mesenchymal stem cells (BMSCs). Scaffolds were implanted into a 4-mm bone defect created in the femur of adult rats, and the new bone fraction was determined using micro-CT scanning at one-month follow-up. The PCL-Sal scaffold had a structure, porosity, and fiber diameter suitable for bone construction. It also possessed a higher rate of hydrophilicity and bioactivity compared to the nPCL, providing a suitable surface for the proliferation and bone differentiation of BMSCs. Furthermore, PCL-Sal scaffolds showed a higher capacity to scavenge free radicals compared to nPCL. The improved bone healing potential of the PCL-Sal scaffold was also confirmed according to in vivo implantation results. Our findings revealed that the salicin-laden implant could be considered for bone repair due to desirable characteristics of salicin such as hydrophilicity, surface modification for cell attachment, and antioxidant properties.

Association between aspirin use and risk of dementia: a systematic review and meta-analysis

PURPOSE

Dementia and Alzheimer's disease (AD) pose significant challenges to public health globally with no effective treatment strategies available. Therefore, the research focuses on developing effective prophylaxis to prevent the onset of these diseases. Recent studies have suggested that low-dose aspirin may help reduce the risk of dementia. Nonetheless, evidence regarding the correlation between aspirin consumption and the onset of dementia and AD is limited. This review aims to provide an up-to-date summary of the existing evidence and evaluate the association between aspirin and the onset of dementia and Alzheimer's disease.

METHODS

A systematic search of PubMed, Embase, Web of Science, PsycINFO, and CINAHL databases was conducted to find eligible studies published until April 2023. A random-effects meta-analysis of the eligible studies was then performed to assess the link between aspirin use and the onset of dementia and Alzheimer's disease. Additionally, we conducted subgroup analyses to evaluate the overall effect of low-dose (75-100 mg) aspirin consumption on the onset of dementia and AD.

RESULTS

A total of 875 studies were identified, with only 22 meeting the inclusion criteria. There was no statistically significant impact of aspirin consumption on the onset of dementia (HR 1.13, 11 studies) or Alzheimer's disease (HR 0.91, 3 studies). Additionally, subgroup analysis showed that taking low doses of aspirin (75-100 mg) did not significantly affect the onset of either dementia (HR 0.96, 13 studies) or Alzheimer's disease (HR 0.85, 2 studies).

CONCLUSIONS

Aspirin use does not decrease the risk of dementia or AD, even when taken in low doses. However, the quality of the studies analyzed was inadequate, with only three randomized controlled trials included in the review. Future high-quality studies are needed to assess the effect of aspirin consumption on these diseases. These findings may assist clinicians in selecting appropriate prophylactic strategies for patients at risk of developing dementia and AD.

Incidence of rebound salicylate toxicity following cessation of urine alkalinization

INTRODUCTION

Management of patients with salicylate toxicity frequently requires urine alkalinization to enhance excretion of salicylate. One strategy for determining when to stop urine alkalinization is to wait for two consecutive serum salicylate concentrations to be less than 300 mg/L (2.17 mmol/L) and declining. When alkalinization of the urine ceases, a rebound in serum salicylate concentration can occur from tissue redistribution or delayed gastrointestinal absorption. Whether this can lead to rebound toxicity is not well understood.

METHODS

This was a single-center, retrospective review of cases with a primary ingestion of acetylsalicylic acid reported to the local poison center over a five-year period. Cases were excluded if the product was not listed as the primary ingestion or if there was no serum salicylate concentration documented after discontinuation of intravenous sodium bicarbonate infusion. The primary outcome was the incidence of serum salicylate rebound to a concentration greater than 300 mg/L (2.17 mmol/L) after discontinuation of intravenous sodium bicarbonate infusion.

RESULTS

A total of 377 cases were included. Of these, eight (2.1%) had a serum salicylate concentration increase (rebound) after stopping the sodium bicarbonate infusion. All these cases were acute ingestions. Five of the eight cases had rebound serum salicylate concentrations that were greater than 300 mg/L (2.17 mmol/L). Of these five patients, only one reported recurrent symptoms (tinnitus). Prior to stopping urinary alkalinization, the last or the last two serum salicylate concentrations were less than 300 mg/L (2.17 mmol/L) in three and two cases, respectively.

CONCLUSIONS

In patients with salicylate toxicity, the incidence of rebound in serum salicylate concentration after cessation of urine alkalinization, is low. Even if serum salicylate rebounds to supratherapeutic concentrations, symptoms are often absent or mild. Routine repeat serum salicylate concentrations after urine alkalinization is stopped may be unnecessary unless symptoms recrudesce.

Salicylic acid and jasmonic acid in elevated CO2-induced plant defense response to pathogens

Plants respond to elevated CO₂ (eCO₂) via a variety of signaling pathways that often rely on plant hormones. In particular, phytohormone salicylic acid (SA) and jasmonic acid (JA) play a key role in plant defense against diverse pathogens at eCO₂. eCO₂ affects the synthesis and signaling of SA and/or JA and variations in SA and JA signaling lead to variations in plant defense responses to pathogens. In general, eCO₂ promotes SA signaling and represses the JA pathway, and thus diseases caused by biotrophic and hemibiotrophic pathogens are typically suppressed, while the incidence and severity of diseases caused by necrotrophic fungal pathogens are enhanced under eCO₂ conditions. Moreover, eCO₂-induced modulation of antagonism between SA and JA leads to altered plant immunity to different pathogens. Notably, research in this area has often yielded contradictory findings and these responses vary depending on plant species, growth conditions, photoperiod, and fertilizer management. In this review, we focus on the recent advances in SA, and JA signaling pathways in plant defense and their involvement in plant immune responses to pathogens under eCO₂. Since atmospheric CO₂ will continue to increase, it is crucial to further explore how eCO₂ may alter plant defense and host-pathogen interactions in the context of climate change in both natural as well as agricultural ecosystems.

Honorary Professor Garry Graham

An appreciation of the contribution of Professor Gary Graham to anti-inflammatory and antirheumatic pharmacology and clinical pharmacology.

GETECCU 2020 guidelines for the treatment of ulcerative colitis. Developed using the GRADE approach

INTRODUCTION

Since the first edition of the Guidelines was published in 2013, much information has been generated around the treatment of ulcerative colitis, and new drugs and action protocols have been introduced. Clinical practice has changed substantially, warranting new approaches and a comprehensive review and update of the evidence.

MATERIAL AND METHODS

Once again, we used the GRADE approach, supported by an electronic tool (https://gradepro.org). The clinical scenarios are the same as in the previous version (induction and maintenance in severe and mild-moderate flare-ups), as are the variables and their evaluation. However, in the updated guidelines, three questions have been deleted, 14 added and 30 maintained, making a total of 44 clinical questions. After an exhaustive review of the evidence, the recommendations are now updated.

RESULTS

Of the 44 questions analysed, no recommendation could be established in two due to the very low quality of the evidence, while in the other 42, based on different degrees of quality of evidence, recommendations were made according to the GRADE system. In 25 of these questions the final recommendation is strongly in favour, in six strongly against, in seven weakly in favour and in four weakly against. According to the scenarios and recommendations, six algorithms are proposed as a simple guide for practical decision-making.

CONCLUSIONS

The aim of this update of the 2013 guidelines is to provide answers, based on the GRADE approach, to the different questions we ask ourselves daily when deciding the most appropriate treatment for our patients with ulcerative colitis in the different clinical scenarios.

Postmortem diagnostics of assumed suicidal food anaphylaxis in prison: a unique case of anaphylactic death due to peach ingestion

Suicidal ingestion of food which the victim is aware they are allergic to is an exceptional occurrence in the forensic field. To the best of our knowledge, no cases of suicidal food anaphylaxis have been reported to date. Therefore we present the first case described in the literature. A 30-year-old prisoner was found dead inside his cell with the remains of a peach remains next to his body, and a handwritten farewell note in his pocket. The autopsy revealed only non-specific findings, while laboratory investigations (serological, toxicological, histological, and immunohistochemical) played a pivotal role in determing the cause and manner of death. In particular, a high titer of both total and specific IgE antibodies was detected, as well as an increase of the tryptase level in cadaveric blood. Moreover, a massive concentration of salicylates was measured in the gastric contents. Microscopically, cellular residues characterized by a vegetal structure were observed in the gastric contents and elements suggestive of mast cells were detected in the glottis, lungs, and myocardium. The immunohistochemical investigation with anti-CD117 and anti-tryptase antibodies showed positivity for mast cells, some of which appeared degranulated. Such findings were entirely consistent with an acute systemic anaphylactic reaction triggered by allergy. Therefore, the prisoner’s death was attributed to self-induced food anaphylaxis caused by the ingestion of peaches. This conclusion was achieved based only on circumstantial data, anamnestic information, autopsy findings, and multiple laboratory results. This integrated approach should be used to pursue a post-mortem diagnosis of anaphylaxis.

Topical delivery of salicylates

Salicylates have a long history of use for pain relief. Salicylic acid and methyl salicylate are among the widely used topical salicylates namely for keratolytic and anti-inflammatory actions, respectively. The current review summarises both passive and active strategies, including emerging technologies employed to enhance skin permeation of these two salicylate compounds. The formulation design of topical salicylic acid targets the drug retention in and on the skin based on the different indications including keratolytic, antibacterial and photoprotective actions, while the investigations of topical delivery strategies for methyl salicylate are limited. The pharmacokinetics and metabolisms of both salicylate compounds are discussed. The current overview and future perspectives of the topical delivery strategies are also highlighted for translational considerations of formulation designs.

Methyl salicylate is the most effective natural salicylic acid ester to close stomata while raising reactive oxygen species and nitric oxide in Arabidopsis guard cells

Modulation by salicylic acid (SA) and its six esters of stomatal closure was evaluated in Arabidopsis thaliana. The seven compounds tested are salicylic acid (SA), acetylsalicylate (ASA), methyl salicylate (MeSA), propyl salicylate (PrSA), amyl salicylate, benzyl salicylate, and salicin. Among these, MeSA was the most effective to induce stomatal closure, followed by salicin and SA, while ASA was the least effective. Since SA, ASA, and MeSA could modulate plant function, the effects of these three compounds on the levels of reactive oxygen species (ROS) or nitric oxide (NO) in guard cells were studied. MeSA and SA raised the content of ROS or NO in as with ABA. The extent of ROS/NO production in response to ASA was the lowest. Reversal by cPTIO or catalase of stomatal closure by MeSA indicated the essentiality of NO and ROS for stomatal closure. Further studies revealed peroxidase as the ROS source during stomatal closure by MeSA, unlike the dominant role of NADPH oxidase in ROS production induced by ABA. The rise in NO production by ABA or MeSA was dependent on nitrate reductase and NO synthase-like enzyme. Given its most effective nature, MeSA can be an excellent tool to examine the signaling components in guard cells and other plant tissues. The ability of MeSA to induce stomatal closure is physiologically relevant because of its volatile nature, stability, and systemic action.

Compound-specific responses of phenolic metabolites in the bark of drought-stressed Salix daphnoides and Salix purpurea

The bark of willows (Salix spp.) is rich in bioactive phenolic compounds from different compound classes and is therefore used as an herbal remedy. The accumulation of these secondary plant metabolites is influenced by environmental factors, including the availability of water. To analyze the influence of drought stress on the profile of phenolic metabolites in willow bark, a pot experiment with Salix daphnoides Vill. and Salix purpurea L. was conducted. Plants were subjected to three irrigation treatments for four and ten weeks: 65-75% field capacity (well-watered), 33-38% field capacity (moderate drought), and 17-22% field capacity (severe drought). Shoot biomass and proline content were assessed as drought-sensitive traits. Contents of phenolic compounds were analyzed by high-performance liquid chromatography. Drought stress reduced shoot biomass and led to an increase of the bark proline content. The particular effects on phenolics depended on the individual compound, Salix species and drought stress duration. Whereas salicylates were not affected, some flavonoids and phenolic acid derivatives, as well as salireposide indicated treatment effects. The effects comprised decreasing as well as increasing contents. However, beyond the impact of drought stress, the observed responses are assumed to be superimposed by seasonal changes in the content of phenolics. Regarding the yield of willow shoots, the impairment of growth under water shortage seems to be more decisive than drought-induced changes of the bark metabolite content.

Common Toxidromes and the Role of Extracorporeal Detoxification

Extracorporeal modalities have been used for detoxification for decades, with hemodialysis the preferred and most commonly used modality. Salicylates, lithium, methanol, and ethylene glycol are the most common poisonings treated with dialysis. For each of these common poisonings, a description of the toxidrome including pharmacokinetics, clinical presentation, an overview of treatment, and the role and application of dialysis is outlined. Inhibition of alcohol dehydrogenase to prevent the formation of toxic metabolites in methanol and ethylene glycol is discussed in detail, including the use of fomepizole and ethanol to complement and in some cases prevent the need for hemodialysis. Hemodialysis has been attempted to treat many poisonings, often without success. A description of EXTRIP (Extracorporeal Treatments in Poisoning), a multidisciplinary project examining the evidence for extracorporeal treatments in poisoning, is also described. Recommendations for poisoning with acetaminophen, baclofen, barbiturates, carbamazepine, digoxin, metformin, phenytoin, thallium, theophylline, tricyclic antidepressants, and valproic acid are provided in a comprehensive table.

Worms on drugs: ecotoxicological effects of acetylsalicylic acid on the Polychaeta species Hediste diversicolor in terms of biochemical and histological alterations

Pharmaceuticals are important environmental stressors since they have a worldwide use; they are usually released in the aquatic compartment without adequate treatment, and because of their intrinsic properties, they may affect several non-target organisms. Acetylsalicylic acid (ASA), the active substance of aspirin, is a non-steroidal anti-inflammatory drug, being one of the most widely prescribed analgesics in human medical care. Consequently, this compound is systematically reported to occur in the wild, where it may exert toxic effects on non-target species, which are mostly uncharacterized so far. The objective of the present work was to assess the acute and chronic effects of ASA on selected oxidative stress biomarkers [catalase (CAT), glutathione reductase (GRed), glutathione peroxidase (GPx), glutathione S-transferase (GST)], lipid peroxidation (thiobarbituric acid-reactive substance), and histological alterations in the polychaete Hediste diversicolor (Annelida: Polychaeta). The obtained data showed that ASA is not exempt of toxicity, since it was responsible for significant, albeit transient, changes in biomarkers related to the redox status of the organisms, occurring as an increase in the activity of catalase in the individuals exposed acutely to ASA. Chronic exposure to ecologically relevant concentrations of this drug showed to be mostly ineffective in promoting any significant biochemical alteration in H. diversicolor. However, histochemical observations revealed proliferation of mucous cells in the tegument of chronically exposed individuals to ASA.

Which Fruits and Vegetables Should Be Excluded from a Low-Salicylate Diet? An Analysis of Salicylic Acid in Foodstuffs in Taiwan

BACKGROUND

Eliminating pseudoallergens is an important element of managing chronic spontaneous urticaria (CSU). Salicylic acid (SA) is a primary pseudoallergen in plant-based foodstuffs. Current dietary recommendations are not applicable in East Asia because data on the SA content of many vegetables and fruits commonly consumed in this region are lacking.

METHODS

We therefore determined the concentration of free SA in 79 popular vegetables and fruits frequently consumed in Taiwan using gas chromatography-mass spectrometry.

RESULTS

The SA content ranged from 0.09 to 2.3 mg/kg in the fresh vegetables examined, and from 0.01 to 0.48 mg/kg in the fruits.

CONCLUSIONS

Data regarding the SA content of East Asian vegetables and fruits could help CSU patients limit their pseudoallergen consumption.

Salicylate-based phytopharmaceuticals induce adaptive cytokine and chemokine network responses in human fibroblast cultures

BACKGROUND

Cytokines and chemokines (CC) play a central role in immunoregulatory and inflammatory processes. Neutralising antibodies for single proinflammatory cytokines have developed into a powerful, though expensive and not always curative therapeutic strategy for severe diseases. Considering the redundancy of CC functions, network (N) rather than single target approaches are essential. Phytopharmaceuticals, common adjuvant therapies, are known modulators of a broad spectrum of CCs, but as complex mixtures with multiple targets they have not been systematically investigated. We investigated the effect of clinically established salicylate-based phytopharmaceuticals alone or in combination on CCNs under non-inflammatory and inflammatory conditions, using fibroblasts being a major source of cytokines in connective tissue diseases.

METHODS

Synchronised human skin fibroblasts (HSKF) were treated for 6 h with standardised fluid plant extracts (E) of Populus tremula L. [end concentration: 0.06%, 0.1%], Solidago virgaurea L. [0.02%, 0.1%], Fraxinus excelsior L. [0.02%, 0.1%], an established combination of the three extracts-STW1 [0.05, 0.1%] and acetyl salicylic acid (ASA) [30 µg/ml], individually or in the presence of lipopolysaccharides (LPS) [10 µg/ml]. Cell lysates were profiled for 23 cytokines. Supernatants were investigated for IL-6 and IL-8 release (ELISA). Total RNA was isolated for gene-expression profiling.

RESULTS

Under non-inflammatory conditions P. tremula E and ASA increased cellular proteins (P) IL-8 and IL-10; S. virgaurea E modulated IL-1α, IL-10, IL-15 and Groα (P). F. excelsior decreased IL-1α and IL-15 (P). The combination of the three extracts (STW1) modulated IL-1α, IL-3 and TNF-ß (P). LPS stimulation increased cellular IL-8, Groα, MCP-1 and RANTES (P) and increased the secretion of IL-6 and IL-8 into the medium. Under these inflammatory conditions F. excelsior reduced GMCSF, GCSF and RANTES. STW1 reduced IL-1α, IL-8, Groα, and MCP-1(P). Secretion of IL-8 and IL-6 was reduced by STW1 and ASA. Gene expression profiles supported non-additive CCN profiles.

CONCLUSION

Salicylate based phytopharmaceuticals provoke cellular pro-and anti-inflammatory CCN responses under non-stress conditions, which adapt to anti-inflammatory responses after LPS-stimulation. CCN-profiles of the single extracts are not additives in combination. A simultaneous activation of cellular pro- and anti-inflammatory cytokines might heighten the immunological reactivity status of a cell.

Treatment with high dose salicylates improves cardiometabolic parameters: Meta-analysis of randomized controlled trials

INTRODUCTION

There is conflicting evidence regarding the efficacy of high dose salicylates in improving cardiometabolic risk in healthy and type 2 diabetes patients. We aimed to determine whether treatment with salicylates at an anti-inflammatory dose (≥1g daily) would improve cardiometabolic risk in healthy individuals and type 2 diabetes patients, compared to placebo.

METHODS

Medline, Medline-in-process, Embase, and all EBM databases were searched for studies published up to December 2016. Twenty-eight articles from 24 studies comprising 1591 participants were included. Two reviewers independently assessed the risk of bias and extracted data from included studies. Meta-analyses using random-effects model were used to analyze the data.

RESULTS

High dose salicylates (≥3g/d) decreased fasting glucose (MD -0.4mmol/l, 95% CI -0.54, -0.27) and glucose area under the curve (MD -0.41mmol/l, 95% CI -0.81, -0.01). Salicylates (≥3g/d) also increased fasting insulin (MD 2.4 μU/ml, 95% CI 0.3, 4.4), 2-h insulin (MD 25.4 μU/ml, 95% CI 8.2, 42.6), insulin secretion (MD 79.2, 95% CI 35, 123) but decreased fasting C-peptide (MD -0.11nmol/l, 95% CI -0.2, -0.04), insulin clearance (MD -0.26l/min, 95% CI -0.36, -0.16) and triglycerides (MD -0.36mmol/l, 95% CI -0.51, -0.21) and increased total adiponectin (MD 1.97μg/ml, 95% CI 0.99, 2.95). A lower salicylate dose (1-2.9g) did not change any cardiometabolic parameters (p>0.1). No significant difference was observed between those receiving salicylates and placebo following withdrawal due to adverse events.

CONCLUSIONS

High dose salicylates appear to improve cardiometabolic risk factors in healthy individuals and type 2 diabetes patients.

PROSPERO REGISTRATION NUMBER

CRD42015029826.

Drug-induced hyperthermic syndromes: part I. Hyperthermia in overdose

Drugs and natural compounds that affect the thermoregulatory system can induce or contribute to hyperthermia when used in excess. Hyperthermia associated with drug overdose is dangerous and potentially lethal. This article reviews the body's process of maintaining thermodynamic equilibrium, and describes the mechanisms by which it is influenced by sympathomimetic and anticholinergic drugs, salicylates, and thyroid replacement medications. Appropriate treatment strategies such as cooling and the administration of counteractive medications are discussed.

[Mucosal healling: a realistic aim or marketing myth?]

The classical aim of the treatment of ulcerative colitis is to induce and maintain remission. However, this aim has not been shown to prevent long-term complications. Current treatment goals attempt to prevent complications. In some studies, healing of the intestinal mucosa has been shown to improve long-term outcomes. In ulcerative colitis, mucosal healing reduces recurrence, the risk of colorectal cancer and the need for surgery, and improves patients' quality of life. The drugs for which there is greatest evidence of their efficacy in inducing and maintaining mucosal healing are salicylates and biological agents. In the near future, endoscopic monitoring may be required to evaluate response to the treatment and decisions may have to be taken according to the persistence or disappearance of these lesions.

Mesalamine hypersensitivity and Kounis syndrome in a pediatric ulcerative colitis patient

5-aminosalicylic acid (mesalamine) rarely induces hypersensitivity reactions. If chest pain associated with atypical electrocardiographic changes are seen during its administration, one should always bear in mind typeIvariant of Kounis syndrome. This variant includes patients, of any age, with normal coronary arteries, without predisposing factors for coronary artery disease, in whom the acute release of inflammatory mediators from mast cells can induce either sudden coronary artery narrowing, without increase of cardiac enzymes and troponins, or coronary artery spasm that progresses to acute myocardial infarction, with elevated cardiac enzymes and troponins.