Oxidative stress and persistent airway inflammation are thought to be important contributors to the development of chronic obstructive pulmonary disease (COPD). This review summarizes the evidence for targeting oxidative stress and inflammation in patients with COPD with mucolytic/antioxidant thiols and inhaled corticosteroids (ICS), either alone or in combination.Oxidative stress is increased in COPD, particularly during acute exacerbations. It can be triggered by oxidant air pollutants and cigarette smoke and/or by endogenous reactive oxygen species (ROS) released from mitochondria and activated inflammatory, immune and epithelial cells in the airways, together with a reduction in endogenous antioxidants such as glutathione (GSH). Oxidative stress also drives chronic inflammation and disease progression in the airways by activating intracellular signalling pathways and the release of further inflammatory mediators. ICS are anti-inflammatory agents currently recommended for use with long-acting bronchodilators to prevent exacerbations in patients with moderate-to-severe COPD, especially those with eosinophilic airway inflammation. However, corticosteroids can also increase oxidative stress, which may in turn reduce corticosteroid sensitivity in patients by several mechanisms. Thiol-based agents such as erdosteine, N-acetyl L-cysteine (NAC) and S-carboxymethylcysteine (S-CMC) are mucolytic agents that also act as antioxidants. These agents may reduce oxidative stress directly through the free sulfhydryl groups, serving as a source of reducing equivalents and indirectly though intracellular GSH replenishment. Few studies have compared the effects of corticosteroids and thiol agents on oxidative stress, but there is some evidence for greater antioxidant effects when they are administered together. The current Global Initiative for Chronic Obstructive Lung Disease (GOLD) report supports treatment with antioxidants  in addition to standard-of-care therapy as they have been demonstrated to reduce COPD exacerbations. However, such studies have demonstrated that NAC and S-CMC reduced the exacerbation risk only in patients not treated with ICS, whereas erdosteine reduced COPD exacerbations irrespective of concomitant ICS use suggesting that erdosteine has additional pharmacological actions to ICS.Further clinical trials of antioxidant agents with and without ICS are needed to better understand the place of thiol-based drugs in the treatment of patients with COPD. The pathogenesis of chronic obstructive pulmonary disease (COPD) is complex and not yet fully understood but is characterised by the presence of both oxidative stress and persistent airway inflammation. Typically, there is an abnormal inflammatory immune response of the lungs to air pollutants, such as ozone, nitrogen dioxide, combustion particulates and gases, usually from cigarette smoke and oxidant air pollution . The infIn the recent Rome Proposal, a COPD exacerbation was described as an event characterised by an acute burst of airways inflammation due to stimuli  that is coupled with worsening of existing airflow limitation, leading to worsening symptoms (dyspnoea and/or cough and sputum), which may be accompanied by tachypnea and/or tachycardia . For mos2−), which can lead to the formation of other reactive oxygen species (ROS), including hydroxyl radicals (OH−) and hydrogen peroxide (H2O2); ROS are cleared by endogenous antioxidants [The presence of inflammation in the lungs of patients with COPD is intimately linked to oxidative stress , 9, whicoxidants . The baloxidants .Oxidative stress is markedly increased in patients with COPD, especially during acute exacerbations, and contributes to the pathology of the disease , 13. It ROS are signalling molecules that influence many processes , and canROS cause tissue damage via lipid peroxidation and oxidation of both proteins and carbohydrates, leading to carbonyl stress, with accumulation of reactive carbonyls and subsequent protein carbonylation . In turnGSH is a low-molecular-weight thiol present in cells at millimolar concentrations. It plays important roles in cellular defence against oxidant stimulation, in redox regulation of protein thiols and in maintaining redox homeostasis, which is essential for the proper functioning of cellular processes including apoptosis . GSH actAntioxidant capacity in the lung is substantially reduced and oxidative stress can persist long after the cessation of cigarette smoking or an acute exacerbation of COPD owing to continued production of ROS from endogenous sources , 12. TheStudies in COPD patients have shown that GSH levels are increased in the bronchoalveolar lavage (BAL) fluid of smokers versus non-smokers and are reduced during severe exacerbations compared with stable COPD .To achieve therapeutic levels, high doses of GSH must be administered because it has a short half-life in blood plasma. Furthermore, GSH cannot cross cell membranes, but first needs to be broken down into its constituent amino acids and then re-synthesised inside the cell. To overcome these limitations of GSH, pro-GSH molecules could be used to restore or increase GSH levels .Suppression of the inflammatory response is a valid therapeutic goal for patients with COPD that aims to improve symptoms such as cough and mucus secretion, improve health status and reduce exacerbations .Corticosteroids are currently the main class of anti-inflammatory drugs used in the treatment of COPD to prevent exacerbations. Although these drugs are known to effectively suppress airway inflammation in subjects with asthma, their effect on the inflammation in COPD remains unclear . The valIt has been suggested that the heterogeneity of patients with COPD necessitates different treatment strategies for different subgroups of patients . In the Dual bronchodilation therapy plays a fundamental role in the treatment of the general COPD population, while ICS-containing therapy provides clinical benefit in the subgroup of patients with significant blood eosinophilia or a high-risk for exacerbation . HoweverThere is evidence that oxidative stress may reduce corticosteroid sensitivity in COPD by mechanisms involving phosphorylation of the glucocorticoid receptor (GR) as well as phosphorylation and inactivation of histone deacetylase-2 (HDAC-2) –41. A poSeveral preclinical studies have shown that corticosteroids retain some activity in the presence of oxidative stress. In a study from 1997, dexamethasone administered subcutaneously displayed antioxidant properties in the lungs of adult rats, with an increase in antioxidant enzymes  that was achieved by enzyme induction rather than through an activation process . Also, pParadoxically, corticosteroids can also increase oxidative stress. Although acute administration of methylprednisolone to rats increased antioxidant levels in lung tissue, suggesting potential benefits of corticosteroid use during acute events, chronic administration of methylprednisolone increased lung lipid peroxidation levels, indicating an increased risk of oxidative lung injury . There aDrugs containing the thiol moiety (–SH) or that are metabolised to thiol-containing species, such as N-(carboxymethylthioacetyl)-homocysteine thiolactone (erdosteine), N-acetyl-L-cysteine (NAC) and S-carboxymethylcysteine (S-CMC) Fig. , have be2O2-induced oxidative stress and DNA damage in lung epithelial cells through the scavenging of intracellular ROS [Erdosteine Fig. a is a prular ROS .Studies in COPD patients provide supportive clinical evidence that erdosteine is effective against oxidative stress . Erdoste2– and H2O2 are too low to make a significant contribution to oxidant scavenging [vivo model of COPD exacerbation induced by lipopolysaccharide (LPS) [NAC Fig. c is alsoavenging . Indirecde (LPS) , 70, andde (LPS) .S-CMC Fig. d is a th1 response to salbutamol [Several studies have compared the antioxidant activity of these different thiol agents. In an in vitro study comparing the inhibitory effects of erdosteine (Met 1), S-CMC and NAC on ROS produced by stimulated rat neutrophils, guinea pig eosinophils and human neutrophils, the effects of S-CMC and NAC were weaker than those of erdosteine . In a cllbutamol . The antlbutamol .Few experimental studies or clinical trials in COPD patients have directly compared the effects of corticosteroids versus thiol agents on oxidative stress.In an in vitro study of bronchial epithelial cells exposed to the oxidant activities of cigarette smoke extracts, S-CMC, but not fluticasone propionate, reduced ROS production, increased GSH, heme oxygenase-1 and HDAC-2 nuclear expression/activity . In contTreatment of COPD patients with oral corticosteroids, even for a short time, resulted in lower plasma MDA levels, an effect attributable to inhibition of lipid peroxidation, while NAC showed no significant effect on oxidant/antioxidant status, as measured by MDA or SOD levels .In a study examining whether ICS and NAC have any effect on oxidative stress markers in patients with stable COPD, fluticasone propionate administered for 10 weeks led to a small improvement from baseline in the systemic redox balance by increasing GPX activity, whereas 10 weeks of NAC tended to decrease interleukin (IL)-8 levels in sputum, but did not affect trolox equivalent antioxidant capacity (TEAC), which reflects antioxidant activity against ROS and reactive nitrogen species .The different antioxidant mechanisms activated by corticosteroids and thiols suggest that a combination of these two classes of drug may be useful in counteracting oxidative stress. A synergistic antioxidant effect was observed when budesonide and erdosteine were administered together to stimulated human neutrophils undergoing respiratory bursts . NAC incA small study in COPD patients compared the effects on oxidative stress of 6-months treatment with unapproved high-dose NAC (1200 mg/day) alone or in combination with an ICS . MDA plaIn cellular and animal models of steroid insensitivity mediated by oxidative stress, S-CMC restored steroid sensitivity by increasing HDAC-2 expression/activity through elevating GSH and SOD levels, reducing oxidative stress, enhancing HDAC-2 recruitment and reducing H4 acetylation in the IL-8 promoter region, and eventually alleviating inflammation and lung damage , 89.S-CMC alone and combined with beclomethasone dipropionate can counteract the effects of cigarette smoke exposure on chromatin remodelling and increased pro-inflammatory responses in human bronchial epithelial cells in vitro .ICS are widely prescribed in COPD, either alone or in combination with other drugs; reports in the literature estimate that up to 86% of COPD patients are treated with ICS, regardless of COPD severity and exacerbation risk . The higAs oxidative stress is increased in COPD patients, particularly during acute exacerbations , and NACIn 2019, the GOLD international guidelines recommended the use of oral antioxidant mucolytic agents, such as NAC, S-CMC or erdosteine, in patients with COPD who were not receiving ICS, as these agents may reduce exacerbations and improve patient health status . This reThe BRONCUS (Bronchitis Randomized On NAC Cost Utility Study) study indicated the possible benefit of the approved standard dose of NAC (600 mg/day) in reducing exacerbations in patients with moderate-to-severe COPD, but this effect may be limited to patients not treated with ICS . In contThere is only limited clinical evidence of the long-term effects of S-CMC in COPD patients receiving concomitant ICS. In the PEACE study, a randomised, placebo-controlled study in Chinese patients with COPD, there was a non-significant interaction between the preventive effects of S-CMC on acute exacerbations and concomitant ICS use, but > 50% of patients had GOLD stage III or IV COPD and only 16.7% of study participants were receiving ICS and at a low dose . This coThe RESTORE  placebo-controlled study demonstrated that erdosteine administered twice daily at the approved dose (300 mg twice daily) and added to usual maintenance therapy for 12 months, reduced the overall exacerbation rate in patients with moderate or severe COPD and a history of exacerbations in the previous year, many of whom were already receiving ICS . The resA recent Cochrane systematic review with meta-analysis  concludeConsidering the clinical evidence collected over the years (and discussed above), the 2023 GOLD Report confirmed that NAC and S-CMC may reduce exacerbations in COPD patients not receiving ICS, whereas erdosteine has been shown to have a significant effect on exacerbations irrespective of the concurrent treatment with ICS .The question of whether antioxidants should be used instead of ICS or in combination with ICS in COPD patients is widely discussed. The latest GOLD Report confirmed that antioxidants like erdosteine, NAC and S-CMC can be effective as add-on therapy for the treatment of COPD patients. NAC and S-CMC can reduce the risk of exacerbations, but this effect is limited to patients not receiving ICS, while erdosteine has proven to be effective independently of ICS use, thus also in patients using ICS.Although oxidative stress may play an important role in amplifying chronic lung inflammation in COPD, little is currently known about the involvement of oxidative stress in the different phenotypes, endotypes and etiotypes of COPD. Thus, the current recommendations on the use of thiol-based mucoactive drugs in COPD do not allow for personalised therapeutic management.Nevertheless, some experts have recommended that long-term treatment with thiols should be used in patients with exacerbation phenotype without chronic bronchitis, particularly in those with early stages of COPD with less severe airway obstruction, bronchiectasis with COPD overlap phenotype, and bronchitic phenotype with or without history of exacerbation . CombinaHowever, since it remains unclear whether patients with a bronchitis phenotype of COPD benefit more from mucolytic therapy than patients with other phenotypes , further


Breast augmentation surgery, like any other surgery, has potential complications, including the less common complication of pleural effusion. We present a unique case of a 44-year-old female who developed pleuritic chest pain and shortness of breath 10 days after her breast augmentation surgery, with no prior history of cardiac or autoimmune conditions. The temporal relationship between the surgery and the onset of symptoms suggested a possible direct link to the implants. Imaging showed a small- to moderate-sized left pleural effusion, and pleural fluid analysis revealed findings suggestive of a foreign body reaction (FBR), including evidence of mesothelial and inflammatory cells with a lymphocyte percentage of 44% and monocytes of 30%. The patient received intravenous steroids at a dose of 40 mg every eight hours for three days while hospitalized, followed by a tapered oral dose of steroids upon discharge, for over three weeks. Follow-up imaging studies showed complete resolution of the pleural effusion. The diagnosis of pleural effusion resulting from FBR to silicone gel-filled breast implants involves a clinical history, cytopathological examination, and the exclusion of other potential causes. This case highlights the importance of considering FBR as a potential cause of pleural effusion post-breast augmentation surgery. Breast augmentation surgery is a common procedure, with nearly 300,000 surgeries performed per year in the United States . It is tA 44-year-old female patient with a known medical history of hypertension presented to the emergency department with progressive pleuritic left-sided chest pain for 10 days. The pain was located at the anterolateral chest and extended to the back, associated with shortness of breath. The patient denied cough or fever at the time of presentation. The patient had undergone uncomplicated bilateral silicone breast implant placement two weeks prior. Three days after the procedure, the patient started having minimal left-sided chest discomfort that progressed to the level of unbearable pain, 10/10 in severity. The patient had no history of cardiac or autoimmune conditions. Physical examination on presentation showed normal vital signs, no swelling or redness of breasts, and a cleaned, healing surgical wound. Lung examination revealed reduced breathing sounds with dullness to percussion at the left base. Chest X-ray and computed tomography of the chest with contrast showed a small to moderate-sized left pleural effusion  with a lymphocyte percentage of 44% (reference range: 50-100%) and monocytes of 30% (reference range: 0-10%). Pleural fluid cytology showed evidence of mesothelial and inflammatory cells, including numerous macrophages. No malignant cells were found  and an erythrocyte sedimentation rate of 28 mm/hr (reference range: 0-20 mm/hr), and the workup for pneumonia, including sputum cultures and urine antigens for There was a concern for a silicone/foreign body reaction (FBR) to the implants causing a hyperinflammatory immune response without leaking, which could be reflected by reactive inflammatory pleural effusion fully responsive to steroids. The patient was started on intravenous steroids (40 mg every eight hours) for three days as an inpatient, followed by an oral taper of steroids over a three-week period .At the one-month follow-up, the patient reported complete resolution of symptoms, and follow-up imaging studies performed two months after treatment showed complete resolution of the pleural effusion.We report the case of a patient with left-sided pleuritic chest pain with pleural effusion following a silicone breast implant surgery, despite no evidence of implant leak. Notably, the patient had no prior history of cardiac or autoimmune conditions, further supporting the likelihood of the effusion being directly linked to the breast implants.Pleural effusion post-breast augmentation surgery was first described by Stevens et al. in 1987 . PleuralAfter breast implant surgery, an FBR can occur as a result of immune system activation, particularly involving CD4+ cells, dendritic cells, and macrophages. These immune cells communicate closely with fibroblasts, which can result in increased production of collagenous and non-collagenous extracellular matrix proteins . CapsulaBreast implant surgery can trigger an activation of the immune system that may result in complications other than capsular contractures. Chronic inflammation triggered by the presence of silicone in breast implants has been associated with immune deficiencies, autoimmune diseases, and neoplasias in patients who underwent this surgery. Autoinflammatory/autoimmunity syndrome induced by adjuvants (ASIA) is a systemic syndrome where many diverse symptoms such as fatigue, mind fog, hair loss, changes in weight, dry eyes, dry mouth, and depression develop after breast implant surgery ,13.It is reasonable to suspect FBR to silicone breast implants as the cause of our patient's pleural effusion based on its temporal relationship, cytology results, and response to steroids. Despite the absence of silicone in the pleural fluid and no evidence of implant rupture or leakage, FBR is a known complication of breast implants and can cause pleural effusion. The diagnosis of pleural effusion resulting from an FBR to silicone gel-filled breast implants involves a clinical history, cytopathological examination, and the exclusion of other potential causes. FBR is an inflammatory reaction caused by implanted materials, including breast implants, where tissue and inflammatory cells produce cytokines, chemokines, and matrix metalloproteinases. In cases of pleural effusion, cytology typically reveals mesothelial cells, macrophages, and lymphocytes, indicating FBR as the cause of the effusion .Corticosteroids can be an effective treatment option for pleural effusions resulting from inflammation in certain conditions, such as autoimmune diseases and post-cardiac injury syndrome. The anti-inflammatory properties of corticosteroids are believed to reduce pleural fluid production and accelerate its absorption rate, leading to faster resolution of the effusion . StudiesIn our case, the patient's effusion completely resolved with steroid treatment, suggesting this could be a viable therapeutic approach for similar cases. However, long-term monitoring is recommended given the potential for autoimmune diseases and neoplasias associated with breast implants.Silicone breast implant-associated pleural effusion is a rare but important complication that should be considered in patients with pleural effusion of unknown etiology following breast surgery. This case highlights the need for careful evaluation and exclusion of other potential causes of pleural effusion, as well as the importance of recognizing the potential for FBR to silicone implants. Although the prevalence of this complication is relatively low in the literature, accumulating more data on the diagnosis and treatment of this condition is crucial to improving patient outcomes. Additionally, systemic corticosteroids may be effective in treating silicone breast implant-associated pleural effusion, and further studies are needed to evaluate the optimal management of this condition.


Cancer is a major cause of morbidity and mortality among people with inflammatory bowel disease (IBD). Intestinal cancers may arise as a complication of IBD itself, while extra-intestinal cancers may arise due to some of the immunosuppressive therapies used to treat IBD. Colorectal cancer (CRC) and small bowel cancer risks remain elevated among persons with IBD as compared to age-and sex-matched members of the general population, and the lifetime risk of these cancers is strongly correlated to cumulative intestinal inflammatory burden. However, the cumulative risk of cancer, even among those with IBD is still low. Some studies suggest that IBD-CRC incidence has declined over the years, possibly owing to improved treatment standards and improved detection and management of early neoplastic lesions. Across studies of extra-intestinal cancers, there are generally higher incidences of melanoma, hepatobiliary cancer, and lung cancer and no higher incidences of breast cancer or prostate cancer, with equivocal risk of cervical cancer, among persons with IBD. While the relative risks of some extra-intestinal cancers are increased with treatment, the absolute risks of these cancers remain low and the decision to forego treatment in light of these risks should be carefully weighed against the increased risks of intestinal cancers and other disease-related complications with undertreated inflammatory disease. Quality improvement efforts should focus on optimized surveillance of cancers for which surveillance strategies exist  and the development of cost-effective surveillance strategies for less common cancers associated with IBD. Colorectal cancer occurs 1.5–2 times more often in those with IBD than comparable members of the general population and is responsible for as much as 15% of IBD-related deaths.Colorectal cancer risk is strongly associated with cumulative colorectal mucosal inflammatory burden encompassing IBD duration, extent of colorectal involvement, colitis severity, and frequency/chronicity of active disease.Extra-intestinal cancers may complicate IBD treatment with chronic immunosuppressive therapies, due to reduced immune surveillance and/or a direct effect of the medications.Thiopurines have been associated with increased risks of lymphoma and non-melanoma skin cancers. The risks of melanoma and cervical cancer in association with chronic immunosuppressive therapies remain uncertain.Hepatobiliary cancer risk is significantly higher among those with IBD, particularly among persons with co-morbid primary sclerosing cholangitis. Emerging data also suggest a higher risk of lung cancer among those with IBD.While the relative risks of certain cancers are increased in those with IBD, the absolute risks of those cancers remain low and should not be a deterrent to effective therapies to treat IBD.Systematic cancer surveillance strategies currently exist for colorectal cancer, hepatobiliary cancers (if co-morbid primary sclerosing cholangitis), cervical cancers, and skin cancers. Cost-effective surveillance strategies do not currently exist for less common cancers, such as small bowel cancers.Endoscopic surveillance and management of colorectal neoplasia have evolved considerably over the past 10–15 years, leading to higher rates of endoscopic resection of neoplastic lesions and lower rates of surgery. Surgery is now reserved for very high-risk neoplasia cases.Post-colonoscopy colorectal cancers (those arising within three years of a colonoscopy) account for up to 50% of colorectal cancers in persons with IBD, which may be because of inadequate surveillance frequency, suboptimal colonoscopy quality, or altered tumour biology. Regular, high-quality surveillance colonoscopy is important to promote detection and management of neoplastic lesions and reduce the risk of missed cancers.As people with IBD are living longer, gastroenterologists will experience a higher burden of individuals who develop cancer; this may impact treatment decisions/options. As the evidence accumulates, IBD care providers will need to revise their understanding of the implications of current IBD practice on cancer risk and accordingly modify preventive and treatment strategies across the spectrum of cancers observed in these individuals.Intestinal and extra-intestinal cancers can arise as complications of inflammatory bowel disease (IBD) and its treatments, respectively. Cancer is one of the most common causes of death in this population ,2, and cThe risk of some, but not all, cancers are increased among individuals with IBD. The most consistent evidence demonstrates increased risks of: (i) CRC among those with colonic involvement, varying with the extent, severity, and duration of colonic inflammation; (ii) small bowel cancer among those with Crohn’s disease; (iii) lymphoma and non-melanoma skin cancer among those treated with thiopurine medications; and (iv) to some extent, melanoma among those treated with anti Tumor Necrosis Factor (anti-TNF) biologic therapy. Children diagnosed with IBD have also been reported to have increased cancer risk in their adult life.No increase in cancer risk has been reported with vedolizumab or ustekinumab, or with tofacitinib so far among individuals with IBD, although more data are required as these therapies are relatively recent additions to the IBD armamentarium. In addition, no increased risk of cancer with anti-TNF therapy after an index cancer diagnosis has been demonstrated, suggesting lengthy post-cancer drug holidays are unlikely to be necessary. Importantly, the absolute risk of cancers is small even for the cancers demonstrated to be increased with therapy, which is important information for shared decision-making between providers and persons with IBD.In the following sections, we outline important studies that have influenced our understanding of the epidemiology of cancer in IBD, focusing on population-based studies (when available), and highlighting important Canadian studies on this topic. A summary of ranges of estimates of risks across studies included in this article is listed in Intestinal cancers arise in people with IBD as a result of cumulative carcinogenic DNA damage from chronic or recurrent bouts of bowel inflammation . Due to Most population-based studies have reported CRC risk to be elevated among persons with IBD as compared to age- and sex-similar persons without IBD ,21,23,59Since then, multiple population-based studies of CRC risk in IBD have been reported. A study from Northern California conducted between 1998 and 2010, based on the Kaiser Permanente database, reported SIRs for CRC among persons with Crohn’s disease and ulcerative colitis of 1.6  . ConversSeveral population-based studies have further reported a significant decline in CRC incidence over time among persons with IBD ,42, althCRC-related mortality has also been reported to be higher among persons with IBD across studies. The aHR for mortality among persons with IBD in a population-based study from Manitoba was 2.15  . A DanisSmall bowel carcinomas account for 1% to 5% of all gastrointestinal tract cancers in persons with Crohn’s disease and have been historically reported to occur at a 20–30-fold higher rate as compared to persons without IBD ,65. A reCRC incidence continues to be 1.5–2 times higher among persons with IBD as compared to age- and sex-matched members of the general population; a risk ratio that has not appreciably changed over time. This ratio suggests that the observed downward trend in absolute CRC incidence in persons with IBD over the past three decades in several studies may be more related to changing genetic and/or environmental risk factors as opposed to changes in IBD treatment. Increased uptake of colonoscopy screening in society may have played a role in declining CRC risk over time. CRC-related mortality also remains roughly two times higher among persons with IBD as compared to persons without IBD who develop CRC suggesting either more aggressive tumour biology; a higher rate of advanced, incurable cancers at diagnosis among persons with IBD; or a direct effect of increased CRC incidence. Persons with IBD remain at substantially higher risk of developing small bowel cancer as compared to their non-IBD counterparts, likely due to greater difficulty in managing small bowel inflammation and the absence of screening strategies for detecting early small bowel neoplasms. However, the absolute risk of small bowel cancer remains exceedingly low; overall, intestinal cancer risk is likely to always be dominated by CRC risk. Strategies aimed at reducing the CRC potential of IBD, and at improving identification of individuals at higher risk of developing CRC to prioritize colonoscopy or surgery, will be required to attenuate the difference in CRC risk between persons with and without IBD.Extra-intestinal cancers in persons with IBD may arise as a result of reduced immune surveillance in the setting of chronic immunosuppressive therapy or as a direct effect of such therapies. Thiopurines, for example, are photosensitizers and lead to development of mutagenic reactive oxygen species . The mosMany population-based studies have not shown an overall association between IBD and lymphoma risk . HoweverThiopurine use (azathioprine and 6-mercaptopurine) in persons with IBD has been consistently associated with an increased risk of lymphoma . In a reA more recent French nationwide study of 189,289 adults with IBD followed for a median of 6.7 years reported a 2–3-fold higher risk of lymphoma in association with thiopurine  and anti-TNF  monotherapy, and a synergistic effect with combination therapy . The aHR among those receiving combination therapy was 2.35  compared to thiopurine monotherapy and 2.53  compared to anti-TNF monotherapy . NotablyAcross Ontario 2017–2020), the SIR for non-Hodgkin’s lymphoma (NHL) and Hodgkin’s lymphoma among persons with IBD, relative to age- and sex-matched controls, was found to be 1.43  and 1.95 , respectively 17–2020, . To whatFurthermore, research with the DEVELOP registry has demonstrated a clear association between thiopurine use (but not biologic monotherapy) and lymphoma risk in children with IBD . While mMultiple studies have demonstrated a modest association of IBD with melanoma, although the impact of medical therapies on melanoma risk remains uncertain. A meta-analysis of 12 cohort studies between 1940 and 2009, comprising 172,837 persons with IBD, reported an increased risk of melanoma among persons with Crohn’s disease  and ulcerative colitis  . The pooA U.S. administrative claims database study comparing 108,579 people with IBD to matched controls without IBD between 1997–2009, similarly reported an IRR of 1.29 for melanoma among those with IBD  . A natioMost studies have not supported an increased risk of melanoma in association with thiopurine therapy ,80,81. ANMSC, mainly basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), are typically non-fatal cancers that are strongly linked to sun exposure. Studies using U.S. administrative health insurance claims data have reported a higher incidence of NMSC among persons with IBD compared with matched controls  or Crohn’s disease  between 1979 and 2011, matched to 1,508,334 women from the general population, reported that women with ulcerative colitis had increased risks of low-grade  and high-grade  squamous intraepithelial lesions, and women with Crohn’s disease had increased risks of low-grade SIL , high-grade SIL  and cervical cancer , compared with controls  reported no increased risk of cervical cancer among persons with Crohn’s disease  and a decreased risk of cervical cancer in persons with ulcerative colitis  17–2020 r. An earlIn the Manitoba study, combined exposure to corticosteroids and immunosuppressants was associated with increased risk of cervical abnormalities  . FurtherHepatobiliary cancers in people with IBD are more likely to occur as a complication of co-morbid liver or biliary disease—particularly primary sclerosing cholangitis—than as a complication of IBD itself or its treatments. A population-based study from Manitoba reported a higher incidence of hepatobiliary cancers in both Crohn’s disease  and ulcerative colitis  . HoweverA more recent meta-analysis of population-based studies reported pooled RRs of close to 3-fold for biliary tract cancers across three studies , but no increased risk of liver cancer across six studies . Strikingly, a meta-analysis of three population-based cohort studies in persons with pediatric-onset IBD reported a pooled RR of 55.45  for biliary tract cancers. Again, this heightened risk may largely relate to a lower baseline risk of biliary tract cancers in a younger population.A recent population-based study from Ontario 2017–2020) reported a 2.5-fold increased risk of hepatobiliary cancers  17–2020 r. There aAn earlier meta-analysis of population-based studies reported a higher incidence of lung cancer  and bladder cancer  among people with Crohn’s disease, and a lower incidence of lung cancer  among people with ulcerative colitis—as compared to persons without IBD . A more In a recent population-based study from Ontario, a weak association was observed between Crohn’s disease and lung cancer , but no association was observed between IBD and either breast cancer  or prostate cancer  . Across Overall, the risks of extra-intestinal cancers appear to be higher among persons with IBD as compared to persons without IBD, which may be partly driven by chronic systemic inflammation and/or by the immunosuppressive therapies used to treat IBD. Whether individuals with IBD also have increased genetic susceptibility to these cancers remains unknown. Clear signals for increased cancer risks among persons with IBD exist for lymphoma and NMSC (primarily in association with thiopurine therapy), hepatobiliary cancers (mainly in association with co-morbid primary sclerosing cholangitis), and lung cancer. However, the risks of other extra-intestinal cancers have been variable across studies and require further elucidation. A multi-provincial Canadian population-based study aims to investigate the association between anti-TNF and thiopurine therapies and cancer risks in the IBD population. Of particular concern is the potential risk of fatal lymphomas in association with thiopurine therapies in young males. Until more data are available, practitioners should limit excess thiopurine exposure for people with IBD, particularly the elderly and young males, and to maintain vigilance in minimizing the risk of extra-intestinal cancers, such as through following appropriate screening measures and monitoring for early signs of cancer occurrence.Prevention of CRC and CRC-related death have long been important goals in the management of IBD. Historical reports of widespread DNA damage in chronically inflamed colorectal mucosa  , a propeUpdated guidance favours endoscopic management of all colorectal neoplasia with clearly delineated borders and without advanced features suggestive of invasive cancer or submucosal fibrosis, as well as continued endoscopic surveillance, as opposed to surgery, for individuals without high-risk neoplastic findings  or difficult to surveille colons ,118. RefImportantly, several studies have demonstrated high rates of post-colonoscopy CRC (CRC diagnosed within three years following a colonoscopy) among persons with IBD, ranging between 25% and 50% of all CRC diagnosed in this population across studies ,122–124.There are inconsistent data regarding the chemopreventive benefits of IBD therapies, including 5-aminosalicylate acids therapies  and thioThere are no screening or surveillance recommendations for small bowel cancers in IBD due to the lower incidence as compared to CRC and perceived cost-ineffectiveness of routine screening ,64. FortThe American College of Gastroenterology (ACG) recommends screening for biliary tract and gall bladder cancers in the setting of co-morbid primary sclerosing cholangitis and IBD with ultrasound or magnetic resonance cholangiopancreatography along with CA19-9 measurement every six months . ProphylWhile it is unclear whether IBD or its treatments are truly associated with an increased risk of cervical cancer, the American College of Obstetricians and Gynecologists , ACG 13, and an The ACG recommends that all persons with IBD undergo regular skin surveillance for NMSC if they are receiving thiopurine therapy, particularly if they are over the age of 50, as well as regular skin surveillance for melanoma, irrespective of receipt of immunosuppressive therapy . They fuAt present, cancer screening recommendations in persons with IBD are best established for CRC and for biliary cancers in persons with co-morbid CRC, whereas guidance for other cancer screening is limited. It is reasonable for individuals with IBD, particularly those receiving chronic immunosuppressive therapy, to undergo regular skin exams and Pap testing with their family physician. The role of routine screening for small bowel cancers and lung cancers, as well as for other internal cancers, must weigh the benefits of screening against the risks and costs and should be individualized. Formal screening recommendations for these and other rare cancers in persons with IBD need to be developed. A summary of existing screening recommendations for IBD-relevant cancers is provided in Data are limited on the use of immunosuppressive therapies after a cancer diagnosis. Immunomodulators are currently not recommended within 2–5 years after a cancer diagnosis . MountinResearch in large cohorts with long-term follow-up is required to better understand cancer risks faced by those with IBD, particularly in relation to different classes of existing and emerging immunosuppressive therapies. Individual risk factors for treatment-related cancers need to be elucidated. Additionally, cancer risk from IBD itself needs to be distinguished from that related to IBD treatments.A clearer understanding of the importance and optimal methods of cancer screening and prevention is needed. Better defined and more widely available screening and surveillance methods are required for extra-intestinal cancers. Cost-effective screening and surveillance methods are also needed for cancers that are not as easily identifiable in their early stages.Better risk stratification tools to optimize colonoscopy delivery are also required to improve colorectal neoplasia detection in high-risk individuals and defer unnecessary colonoscopy in low-risk individuals.A better understanding of the reasons underlying the high rate of post-colonoscopy colorectal cancers and methods to reduce this occurrence is required.While the risk of developing cancer in persons living with IBD is small, there is still an increased risk of certain cancers that individuals with IBD need to be aware of. The risk of cancer can be associated with the disease itself or the medications used to treat IBD. Even though the prospect of being at a greater risk for cancer development can be worrying for some, patient partners welcome conversations with multidisciplinary providers regarding risk factors and recommended screening for cancers. Receiving this information can facilitate self-advocacy and informed, shared decision making about treatment options and disease management. Patient partners stressed the importance of cancer screening and surveillance to decrease the risk of cancer development or discovering the cancer in its early stages.Individuals with IBD receiving immunosuppressive therapies  should receive regular screening and surveillance for potential treatment-related cancers where screening protocols exist.Lifelong excellent control of bowel inflammation is important to reduce colorectal cancer risk; physicians should have access to the best treatment to control inflammatory burden as required.Beyond treating the underlying IBD, careful high-quality colonoscopy examinations remain the best strategy for CRC prevention and should be available to all individuals with colorectal IBD.Research should be encouraged and funded to develop non-invasive markers of neoplasia in IBD.Shared decision-making should inform treatment choices and cancer risks for IBD, weighing the risks of untreated inflammatory disease against the small, but potentially serious, risks of extra-intestinal cancers with immunosuppressive therapies. The difference between the absolute risks and relative risks of various cancers should be highlighted during these discussions.For individuals with IBD who develop cancer, regular communication between gastroenterologists and oncologists should be encouraged to optimize management.This article appears as part of the supplement “The Impact of Inflammatory Bowel Disease in Canada in 2023”, sponsored by Crohn’s and Colitis Canada, and supported by Canadian Institutes of Health Research Project Scheme Operating Grant (Reference number PJT-162393).


Treatment for stroke is time-dependent, and ambulance services play a vital role in the early recognition, assessment and transportation of stroke patients. Innovations which begin in ambulance services to expedite delivery of treatments for stroke are developing. However, research delivery in ambulance services is novel, developing and not fully understood.To synthesise literature encompassing ambulance service-based randomised controlled interventions for acute stroke with consideration to the characteristics of the type of intervention, consent modality, time intervals and issues unique to research delivery in ambulance services.Online searches of MEDLINE, EMBASE, Web of Science, CENTRAL and WHO IRCTP databases and hand searches identified 15 eligible studies from 538. Articles were heterogeneous in nature and meta-analysis was partially available as 13 studies reported key time intervals, but terminology varied. Randomised interventions were evident across all points of contact with ambulance services: identification of stroke during the call for help, higher dispatch priority assigned to stroke, on-scene assessment and clinical interventions, direct referral to comprehensive stroke centres and definitive care delivery at scene. Consent methods ranged between informed patient, waiver and proxy modalities with country-specific variation. Challenges unique to the prehospital setting comprise the geographical distribution of ambulance resources, low recruitment rates, prolonged recruitment phases, management of investigational medicinal product and incomplete datasets.Research opportunities exist across all points of contact between stroke patients and ambulance services, but randomisation and consent remain novel. Early collaboration and engagement between trialists and ambulance services will alleviate some of the complexities reported.PROSPERO 2018CRD42018075803The online version contains supplementary material available at 10.1007/s10072-023-06910-w. Stroke is the second-largest cause of death worldwide with an estimated 6.7 million deaths every year and the third-largest cause of disability –4. IschaTreating large numbers of patients in this hyperacute time window requires streamlined care pathways which are difficult to achieve through hyperacute hospital services alone . ConsideThere is increasing recognition that prehospital research is fundamental to further enhance hyperacute stroke care . InterveThis review seeks to systematically understand the breadth of randomised interventions trialled for ultra-acute stroke within ambulance service settings and to explore the unique characteristics reported when undertaking randomised controlled trials within ambulance services for hyperacute stroke.This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines  and is rTitles and abstracts of all returned studies were screened by one author (MD), and those meeting the selection criteria were retrieved. Two authors (MD and JPA) independently screened the full papers to confirm the eligibility for inclusion, and any discrepancies were discussed. A record of exclusions was maintained as well as information to support inclusion decisions. The reference lists of included studies were hand-examined for other relevant articles.A trial was considered randomised if the method of randomisation was clearly defined, or if the trial was reported as randomised, and no evidence of a non-randomised method of allocation was recorded. Eligible studies were included where adult patients presented to ambulance services with symptoms of acute stroke, and the randomised intervention was commenced prior to arrival at hospital.Papers were excluded that were not original research, not ambulance service-based, involved inter-hospital transfers where patients had received a diagnosis of acute stroke, or comprised a protocol, review or guideline paper.Risk of bias was assessed in accordance with the Cochrane collaboration’s tool for assessing bias in randomised trials .The following data was extracted and recorded in data tables: study design, setting, study period, inclusion criteria, randomisation strategy, intervention and control, primary outcome, sample size, population demographics, type of consent obtained, presence of doctor , final diagnosis, timings and logistics and any narrative characteristics or challenges unique to the prehospital research environment. Meta-analysis would be considered if sufficient numerical data allows.The search returned 538 references across five databases . Thirty articles were identified through the initial title, and abstract screening of which 15 met the full inclusion criteria  . Lastly. , and pre. ).Primary outcomes can be divided into four distinct groups of, triage/referral decisions and diagnosis , 31, 32,. [A range of randomisation methods were applied. Malekzadeh et al., a control room-based study, quasi-randomly assigned calls as they were received to triage nurses who were either trained or not trained in the trial process . Four tr.  and para.  where PA. . Randomi. , 31, 33.. , 29, 33.All studies reported consent mechanisms with twelve actively seeking informed consent that was either verbal or full Table .Table 2CWhere provisional consent was sought in the ambulance, this was followed by in hospital following positive imaging . HougaarFAST-MAG  requiredThe control centre-based trials did not take consent from patients. Two implemented service changes only with no change of clinical practice at the scene , 21. TheThe two UK-based pilot trials, PIL-FAST and RIGHT, tested a method of consent where paramedics assessed the capacity of the patient and obtained informed consent where capacity was demonstrated , 25. WheOne study failed to complete the consent process for patients enrolled in the control group after initial consent had been sought in the ambulance and resulted in a randomisation imbalance. These data were lost to follow up, and the number of patients that were lost is unknown .Nurmi et al., benefits of stroke treatment in an MSU (BEST-MSU), and Berglund et al. did not report a breakdown by source of consent; however, all indicate that patient consent or next of kin informed consent was obtained with the latter waiving consent in line with hospital routine practice in definitive stroke care , 26, 33.Thirteen of 15 studies reported time intervals , 31–33. The field administration of stroke therapy-magnesium (FAST-MAG) and RIGHT-2 trials reported the additional interventions applied on-scene for stroke did not compromise ambulance response timings and were viewed favourably as improving the quality of care offered to stroke patients , 29. ImpFinally, two studies where ambulances bypassed local hospitals in favour of conveying patients directly to comprehensive stroke centres reported contrasting results. In Sweden, the increased priority afforded to stroke did not adversely affect response to other waiting emergency calls ; howeverStudies reported numerous characteristics unique to research conducted in ambulance-based settings  paramedics trained in RIGHT-2 trial procedures recruited at least one patient. Furthermore, recruitment hours initially limited to typical working hours for research staff availability were extended in RIGHT-2 to encompass 24/7 recruitment reflective of real-world ambulance care to not limit participation and maximise inclusion .Consequently, re-familiarisation with recruitment protocols throughout the recruitment phase and recruitment of new paramedic or ambulance nurse researchers was necessary as some recruitment phases exceeded 60 months , 30, 33.Three trials reported data collection inconsistencies. First, data information sheets were missing in 55.5% of patients enrolled in to the intervention arm of PASTA despite efforts to encourage completion . Second,Two studies  where IMP was stored and randomised within ambulances experienced mislaid IMP. Crucially, the handover point between ambulance and hospital has been identified as a key risk for loss as both reported losses during the transition of care at the point of clinical handover , 29. SeaAll studies were successful in their approach to applying interventions in the ambulance service environment. Two achieved partial success, and one study was limited due to the oversight in capturing re-consent of patients in the control arm, rendering data unreportable . The stuThis review is the first to explore the types of randomised intervention and characteristics of ambulance service-based randomised controlled studies in stroke. Randomised interventions were identified across the chain of contact with ambulance services from detection of stroke and dispatch, clinical intervention on-scene and in-transit, direct referral to primary stroke centres and definitive stroke care delivery at the scene. Aligning to the time-is-brain concept  all inclThe majority of interventions focused on paramedic-led administration of interventions on-scene or in-transit. These are simple, time-efficient, well-suited to the existing prehospital provider’s skillset and widely distributable across large geographical regions without adding significant workload to what can often be disorganised, chaotic and challenging environments –42. WhilRecruitment rate must be considered a real-world factor in planning and facilitating research in prehospital care, and this has been described elsewhere . From a The method of randomisation offers a potential solution. Cluster randomisation by the ambulance station randomises a group of paramedics themselves without adding steps at the scene. This can allow paramedics to carry out research activity without impacting upon clinical care with fewer stages at the patient’s side , 46. ProIt is clear across all trials in this review that patient outcome and the relationship with prehospital time intervals are of interest to investigate. It is challenging to solely assess the effect of time intervals in the prehospital phase because there is major variation in time interval terminology reported. Future collaboration between triallists on reporting of distinct time phases within prehospital stroke will improve homogeneity for future meta-analysis.Mechanisms to obtain explicit informed consent in prehospital trials have often been extrapolated from more established medical settings where similar research pressures are seen . ParamedIncluded studies varied in quality, sample size and population. This was somewhat anticipated due to the novelty of research in the prehospital field. There were some methodological weaknesses identified but these relate to issues unique to the multicentre research in emergency settings and as such, four trials set secondary outcomes to assess the feasibility of ambulance-based research. Indeed, all conclude that prehospital research is feasible, but the unique ambulance-based setting presents challenges that warrant further exploration, especially as the paramedic profession continues to cultivate its research capabilities. Ensuring simplicity in future trial designs will undoubtedly encourage participation, promote interest and protocol compliance from Paramedics often working alone in chaotic and time-pressured environments.We limited studies to those involving an element of randomisation whether true or pseudo, e.g. alternate weeks as used in the mobile stroke unit trials. However, we explored the range and scope of interventions tested and purposely remained broad with no specification of time, language or country limitations.Summarising the literature in this way poses several challenges. First, these conclusions are drawn from a variety of data sources, countries, time periods and patient populations. Skill levels of medical providers on ambulances vary with country, clinical responsibilities and autonomy and experience of prehospital research. Not every study provided detail on the grades of prehospital staff working within each setting. Similarly, the arrangement of wider healthcare systems is too varied limiting the overall ability to draw conclusions. Not all studies report limitations or challenges in conducting research in ambulance services, and there is disparity in reported time intervals making meta-analysis unfeasible. However, this review serves as an initial insight to develop ambulance-based research for all health conditions, not just stroke.A wider review inclusive of prospective, non-randomised and observational trials may broaden the scope and complement this review with an overview of contemporary developments in ambulance-based stroke research.There is heterogeneity of research design and outcomes measured in the existing body of ambulance-based stroke literature. Whilst prehospital research is evolving, randomised activity is clearly feasible and can be undertaken in the prehospital environment with potential developments for stroke across every point of contact with ambulance services without impacting upon timeliness. However, none have yet resulted in a change to ambulance service practice.New methods need to be developed to help extrapolate intervention complexity and balance cost-effectiveness to increase generalisability across the wider practice setting. Early consultation between ambulance services and triallists, drawing on research of prior challenges and lessons learnt will contribute to understanding research complexity in the prehospital environment and mitigate some of the difficulties reported here.It can be concluded from this review, in congruence with the literature, that randomised research is taking place to support prompt identification of stroke , deliverFuture work to overcome challenges within this review to harmonise data acquisition and determine key time parameters will allow broader meta-analysis through collaboration with ambulance services, triallists and stroke networks serving to complement the existing literature in ambulance-based stroke research.ESM 1(DOCX 386 kb)


The gut microbiota plays crucial roles in maintaining the health and homeostasis of its host throughout lifespan, including through its ability to impact brain function and regulate behaviour during ageing. Studies have shown that there are disparate rates of biologic ageing despite equivalencies in chronologic age, including in the development of neurodegenerative diseases, which suggests that environmental factors may play an important role in determining health outcomes in ageing. Recent evidence demonstrates that the gut microbiota may be a potential novel target to ameliorate symptoms of brain ageing and promote healthy cognition. This review highlights the current knowledge around the relationships between the gut microbiota and host brain ageing, including potential contributions to age-related neurodegenerative diseases. Furthermore, we assess key areas for which gut microbiota-based strategies may present as opportunities for intervention. Physiological changes that occur during ageing can contribute to a progressive decline in overall brain health including cognitive abilities. This impairment in brain health is observable in multiple age-related diseases, including mild cognitive impairment (MCI), Alzheimer’s disease (AD), Parkinson’s disease (PD) and multiple sclerosis (MS), and leads to a worsened quality of life for patients. There is an important difference between one’s chronologic age (time since birth) versus one’s biologic age, and differences in the rate of ageing, especially during midlife, can significantly impact future age-related decline . Furthergut microbiota, these microbes have coexisted and coevolved with their host and are increasingly recognised for their contributions to maintaining the health of their host throughout the lifespan, including brain health. The gut microbiota can communicate bidirectionally with the brain through several mechanisms, including endocrinal, nervous, immune and microbial metabolite-driven pathways , worms , rodents, dogs, monkeys  demonstrated a causal role of the gut microbiota in longevity; transferring microbiota from young fish into middle-aged fish improved their lifespan and motor behaviour and was accompanied by distinct transcriptional changes in intestinal immunity  mice who received microbiota from old mice demonstrated increased hippocampal neurogenesis and signs of pro-longevity compared to those who received FMT from young mice, while the same effects did not occur in aged GF mice . HippocaFascinatingly, the gut microbiota from young mice appears to harness properties that enable it to rejuvenate aspects of brain ageing when transferred into aged mice. Two studies recently confirmed similar findings, wherein FMT from young mice to aged mice improved ageing-related deficits in memory and learning ability . MicrobiOn the other hand, it is currently unclear whether ageing-driven changes in the gut are protective or harmful to cognitive health in ageing. For instance, research by Accumulating evidence is revealing associations between the gut microbiota and neurodegenerative diseases associated with ageing, including mild cognitive impairment (MCI), Alzheimer’s disease (AD), Parkinson’s disease (PD) and multiple sclerosis (MS) . In addiFirmicutes and Bifidobacterium, and higher levels of Bacteroidetes, including Bacteroides  from MCI levels to healthy cognition at his 2-month follow-up visit  from early age reduced the amyloid plaque load observed later in life in male mice  is the second most common age-related neurodegenerative disease, and may have unique influences from the gut microbiota initiating disease pathogenesis in the gut . Mouse she brain . While PAkkermansia, Clostridium bolteae and Ruthenibacterium lactatiformans along with reduced levels of Blautia wexlerae, Dorea formicigenerans and Erysipelotrichaceae CCMM and altered microbial β-diversity  is a demyelinating neurodegenerative disease, with a typical age of onset in the 20s to 40s, and ageing can play an important role in disease progression . The majiversity . The abu T cells . Therefo T cells . Further T cells . In term T cells , raisingThe mechanism(s) of action underlying microbiota–gut–brain communication in ageing-related cognitive decline remain elusive. Given the increased inflammation and immunosenescence which occurs during ageing, it is probable that alterations to microbiota-immune signalling contribute to differences in host brain ageing. Indeed, recently literature has demonstrated that some ageing-induced alterations to gut-associated immunity were reversed following FMT from young to aged mice . This FMAkkermansia  and other small molecule secreted metabolites. These molecules are constantly produced by gut bacteria and shape host immunity . Some stpatients . GF wildpatients . GF APP/patients . Colonispatients .Recent literature demonstrated that bacterial-derived metabolite acetate regulates the function of microglia in the brain. In the 5xFAD mouse model of AD, oral administration of acetate to GF mice promoted a pro-inflammatory phenotype in cortical microglia, with reduced phagocytosis of amyloid plaques leading to accelerated pathology . In contIn addition to SCFAs, other microbially-derived metabolites have also been implicated in brain health during ageing. As discussed previously, the microbially-produced metabolite δ-valerobetaine is more abundant in older animals and was found to impair learning and memory abilities . MeanwhiBacteroides species produce indoles, and high level of Bacteroides was linked with increased mortality in 85+ individuals  for 3 months significantly reduced neurofilament-light levels in the serum and modestly improved other serum markers for disease severity, although no improvements to cognition were observed in this timeframe . InteresNonetheless, antibiotics may not be the best treatment approach for multiple reasons, including their potential for triggering harmful neurotoxic side effects. For instance, broad-spectrum antibiotics may deplete beneficial symbiotic gut bacteria, which may be playing critical support roles to the brain during ageing. Several case reports have linked the consumption of antibiotics and high plasma levels of antibiotics with the onset of delirium in the elderly . FurtherSince it is unclear whether the harms of antibiotic use outweigh the potential benefits in individuals that are not actively battling a bacterial infection, and because antibiotic use supports the development of antibiotic-resistant bacteria, the potential for antibiotics as a therapeutic for ageing-associated neurodegenerative diseases may be limited. Therefore, the development of novel antibiotics, such as engineered phages that could specifically eliminate individual identified pathogenic bacteria, could become valuable in treating conditions wherein specific pathogenic gut microbes are identified.Bifidobacterium breve strain could be an effective approach for improving memory functions of subjects with MCI showing improvements in various cognitive domains such as immediate, delayed and visuospatial memory  after 12-weeks supplementation  mildly enhanced cognitive performance in healthy elderly  host brain ageing, including in neurodegenerative diseases, making this an exciting time for research within this scope. Indeed, microbiota-targeted interventions have shown promise for improving cognitive performance and overall brain health during ageing. While this field of research is very young and mechanistic evidence is entirely preclinical, clinical studies involving probiotics and dietary interventions that alter the gut microbiota have shown success at improving aspects of cognition in older people. Furthermore, clinical trials and case studies involving FMT demonstrate promise for improving symptoms of neurodegenerative diseases, including PD, AD and MS, giving hope to the future of medicine for the thousands of individuals living with these diseases who currently have limited treatment options. Nonetheless, this is a rapidly emerging field, and large-scale, well-controlled clinical studies are required to better characterise the potential for the gut microbiota as a treatment target within these diseases.Ageing is a complex biological process, and individual’s age at different speeds and trajectories, which complicates defining healthy ageing, including how the gut microbiota should be modulated to support healthy ageing. Moreover, the impact of biological sex on ageing remains understudied, including how sex shapes age-related physiological changes in the microbiota-host dialogue, regardless of the increasing evidence that suggests biological sex contributes to the susceptibility for several age-related diseases. While the gut microbiota may become a diagnostic tool to better understand an individual’s biological age(ing) , it may A dominant, lingering question is the definition of a healthy gut microbiome, and whether a universal microbiome indicative of health during ageing indeed exists . Technol


Coronary artery disease (CAD) is one of the major causes of mortality and morbidity worldwide, with a high socioeconomic impact. Currently, various guidelines and recommendations have been published about chronic coronary syndromes (CCS). According to the recent European Society of Cardiology guidelines on chronic coronary syndrome, a multimodal imaging approach is strongly recommended in the evaluation of patients with suspected CAD. Today, in the current practice, non-invasive imaging methods can assess coronary anatomy through coronary computed tomography angiography (CCTA) and/or inducible myocardial ischemia through functional stress testing . However, recent trials (ISCHEMIA and REVIVED) have cast doubt on the previous conception of the management of patients with CCS, and nowadays it is essential to understand the limitations and strengths of each imaging method and, specifically, when to choose a functional approach focused on the ischemia versus a coronary anatomy-based one. Finally, the concept of a pathophysiology-driven treatment of these patients emerged as an important goal of multimodal imaging, integrating ‘anatomical’ and ‘functional’ information. The present review aims to provide an overview of non-invasive imaging modalities for the comprehensive management of CCS patients. Coronary artery disease (CAD) is a major cause of morbidity and mortality worldwide, and an accurate diagnostic assessment is pivotal for identifying patients that could potentially benefit from revascularization .A multimodal non-invasive diagnostic approach for CAD detection includes anatomical  and non-invasive functional imaging  ,3.While CCTA accurately depicts coronary anatomy, detects potential stenosis, and evaluates plaque features, other non-invasive functional imaging can demonstrate myocardial ischemia and the corresponding coronary territory. Integrating this complementary information is essential for the global risk assessment and the subsequential management of patients with suspected CAD .The current European Society of Cardiology (ESC) guidelines recommend the use of either anatomical or non-invasive functional imaging as the initial test for diagnosing CAD after a global clinical risk assessment .Which test to prescribe can be sometimes difficult to decide; typically CCTA is the preferred test in patients with a lower range of clinical likelihood of CAD, whereas the non-invasive functional tests for ischemia have better rule-in power and should be therefore preferred in those with higher clinical risk of coronary atherosclerosis . The aimDiagnosing CADGuiding appropriate therapy  in cases where CAD is confirmedAssessing the long-term outcomes and stratifying the risk for patients with CAD.Functional tests designed to identify suspected CAD, with or without cardiac imaging, traditionally serve three important clinical purposes in the field of cardiology:Cost-effectiveness and wide accessibilityAbsence of ionizing radiation Ease of performance, potentially at the bedsideHigh diagnostic accuracy, particularly in terms of specificity for severe/obstructive CAD .Stress echocardiography is commonly utilized as a non-invasive functional test during the diagnostic evaluation of CAD. It possesses the following characteristics:Stress echocardiography aims to detect myocardial ischemia by observing the transient changes in regional function that occur during stress. Specifically, the presence of coronary obstruction leads to reduced blood flow in the sub-endocardial region, resulting in decreased wall thickening and endocardial excursion in the ischemic areas. Stress echocardiography is performed using either exercise or pharmacologic stressors (dobutamine or vasodilator drugs) to induce myocardial ischemia. Furthermore, SE offers relevant information regarding coronary microvascular function, heart valves, or myocardium ,7,8,9,10Exercise, dobutamine, and vasodilators administered at adequately high doses have comparable effectiveness in inducing wall abnormalities in the presence of critical epicardial coronary stenosis . HoweverDespite the distinct pathophysiological mechanisms involved, dipyridamole and dobutamine tests demonstrate similar diagnostic accuracy when appropriately high doses and state-of-the-art protocols are employed . In routVasodilator SE provides the opportunity to incorporate measurements of coronary flow velocity reserve in the left anterior descending coronary artery (CFVR-LAD). This measurement is an important parameter that enhances the specificity of SE evaluation ,14,15 F. HoweverFurthermore, SE can be implemented with speckle-tracking echocardiography (STE). The evaluation of regional wall motion abnormalities (WMA) is based only on myocardium inward motion; STE offers additional information regarding longitudinal myocardial shortening, has been shown to be superior to the visually assessed regional WMA, and is a useful tool for ischemia detection in patients with suspected chronic coronary syndrome ,3.In this setting, the Artificial Intelligence-calculated Left Ventricular Ejection Fraction and Global Longitudinal strain (GLS) are demonstrated to provide incremental sensitivity to detect CAD . ArtificOverall, SE demonstrates very high specificity compared to other functional tests for severe obstructive CAD detection  and showFrom a clinical perspective, if a SE is positive for ischemia and ≥2 segments of the left ventricle show reversible wall motion abnormalities, obstructive CAD is usually diagnosed. On the other hand, the diagnosis of less than severe CAD, which may also cause angina symptoms or cardiac events, is difficult to obtain with standard SE. The global (obstructive or not) CAD burden is clearly better assessed and quantified with CCTA, although a reduced CFVR-LAD during SE may improve the sensitivity for CAD with proven diagnostic benefits ,24,25.Stress-echocardiography has an established prognostic and risk stratification role, not only considering wall motion abnormalities, but also using CFVR-LAD measurement, and other ancillary variables, such as contrast myocardial perfusion ,26,27.Nevertheless, the question of whether SE offers comparable or superior long-term risk stratification compared to anatomical coronary data remains unknown due to the lack of direct comparative studies. Previous studies such as PROMISE and SCOT-HEART have compared coronary CCTA with a combination of various functional tests, but a direct head-to-head examination of SE against anatomical data is lacking ,29.In conclusion, SE continues to be a preferred non-invasive approach for patients with suspected CAD due to its wide availability. Furthermore, SE enables a comprehensive evaluation of cardiac function and the assessment of hemodynamic effects in patients with valvulopathies.Among noninvasive imaging modalities, CMR has been increasingly used in recent years due to its unique qualities in providing a complete assessment in patients with known or suspected CAD . Indeed,In some cases, nuclear imaging may show false negative  or false positive results; in these circumstances, stress-CMR offers better sensibility and specificity in detecting functionally significant CAD .In a few large randomized clinical trials, stress-CMR has been shown to be even superior in detecting ischemia compared to single photon emission computed tomography (SPECT) ,35,36, aIn fact, numerous studies have demonstrated that pathological stress-CMR is associated with a higher risk of cardiac death and adverse events during long-term follow-up ,40,41,42In patients with prior revascularization, a stress-CMR reduces the need for further diagnostic imaging techniques, subsequent coronary angiography, and revascularizations without impairing patients’ prognosis .Stress-CMR can be performed after the injection of a vasodilator substance  which triggers a “coronary steal effect”: In normal myocardium, coronary microcirculation dilates during exercise ensuring adequate tissue perfusion, while in the presence of significantly stenotic coronary arteries, the distal microcirculation is almost maximally dilated even in resting conditions. During or after vasodilator injection, first-pass transit of GBCM is observed through the left ventricular myocardium with a typical wavefront from the subendocardial to the subepicardial region. Typically, 3 short-axis slices are acquired for each heartbeat, and the whole first-pass perfusion scan is performed during one breath-hold ,44. CurrPhase contrast CMR at the coronary sinus allows a valuable estimation of the global left ventricle (LV) myocardial blood flow. This imaging technique has been validated in small studies using positron emission tomography (PET). Recent studies demonstrated a prognostic role of CMR-derived Coronary Flow Reserve (CFR) in CAD patients ,46.Stress-CMR offers a global assessment of myocardial ischemia and myocardial viability in a single examination  47]. Th. Th47]. In cases where vasodilators are contraindicated, the assessment of myocardial ischemia can be conducted through dobutamine infusion. Dobutamine, a positive inotropic and chronotropic agent, raises myocardial oxygen demand, potentially inducing ischemia and resulting in left ventricular wall motion abnormalities in individuals with significant CAD. The protocol for this assessment is similar to that of SE, involving the administration of escalating doses of dobutamine until the target heart rate, equivalent to 85% of the maximal predicted heart rate, is achieved . DobutamThe use of single photon emission computed tomography (SPECT) is currently an established approach in the initial evaluation of patients with suspected CAD thanks to wide availability, standardized protocols, and the extensive data established for diagnostic accuracy. Ischemia can be provoked by exercise or pharmacological stressors (dobutamine) that increase myocardial work and oxygen demand, as in other stress imaging protocols . In caseSingle-photon emission computed tomography implicates the intravenous administration of gamma-emitting radiotracers, which are accumulated by cardiomyocytes in proportion to myocardial blood flow. This uptake occurs during periods of rest as well as during physical or pharmacological stress. The radionuclide agent is typically injected at the peak of exercise or during maximum vasodilation. During stress, a decrease in regional tracer uptake indicates relative myocardial hypoperfusion, whereas reduced uptake both during stress and at rest suggests the presence of a myocardial scar . Two radThe particular pharmacokinetic characteristic of 201Tl is the prolonged retention within the cardiomyocytes allowing the evaluation of the coronary reserve in a single administration immediately after the provocation test. On the contrary, the perfusion study should be performed in two sessions  using the technetium-based tracers, with more favorable dosimetry and improved quality of gated images thanks to their shorter half-life .Currently, myocardial perfusion studies are acquired in a gated mode using an ECG trigger and separate computed tomography (CT) scans are performed for attenuation correction (available for SPECT/CT hybrid machines). This hybrid modality offers the evaluation of the ventricular volumes and function  with an improvement in the diagnostic accuracy of perfusion imaging .Unfortunately, there are some limitations that need to be mentioned. First, SPECT can overlook cases of balanced ischemia . FurtherPositron emission tomography (PET) is another radionuclide imaging technique widely used in the study of ischemic heart disease and other cardiovascular pathologies ,66. ThisMyocyte metabolism shifts to glucose from fatty acids during ischemia. Thus, the lower uptake of a glucose analogue tracer (18F-Fluorodeoxyglucose—FDG) reflects the presence of myocardial ischemia. To evaluate regional perfusion, a tracer that remains in the vascular space and illustrates the distribution of myocardial blood flow (such as nitrogen 13-ammonia or rubidium-82) can be utilized. Consequently, the presence of enhanced FDG uptake in regions with reduced blood flow, known as a “mismatch,” signifies hibernated myocardium. Conversely, when both metabolism and flow show a consistent decrease, termed a “match,” it is believed to indicate necrotic myocardium. The presence of regional dysfunction alongside normal perfusion is an indication of stunning [The advantage of PET imaging is that the myocardial perfusion can be measured directly and quantified in all left ventricular myocardium. This allows the identification of ischemia even in the case of multivessel disease as well as the assessment of microvascular dysfunction .PET with myocardial perfusion imaging (PET-MPI) has some other advantages over SPECT such as lower radiation dose, better image quality, and greater diagnostic accuracy . In factCoronary CT Angiography (CCTA) is the preferred imaging technique in symptomatic patients with a low-intermediate pre-test probability of CAD ,69. The Coronary CT Angiography allows risk stratification of patients with CAD based on the severity of coronary stenoses but also evaluation of the plaque characteristics . ImportaThe specificity of CCTA in CAD is boosted with the integration of anatomical information with functional hemodynamic assessment , which iPerivascular adipose tissue (PVAT) is a fat depot with a paracrine function that produces a wide range of biologically active molecules, which may profoundly influence the vasculature itself ,88.PVAT attenuation, measured with CT imaging is a non-morphological marker of inflammation that was applied to the left atrium, carotid artery, and aorta ,90,91. TInflamed vessels release cytokines that prevent lipid accumulation in PVAT preadipocytes and play a key role in the progression of vascular atherosclerosis. Therefore, in the presence of vascular inflammation adipogenesis is inhibited in favor of lipolysis, and water content increases in the adipose cells. This process shifts overall PVAT attenuation on CT (measured in Hounsfield unit—HU) due to oedema and it is a useful biomarker for the in-vivo assessment of coronary inflammation . OikonomThe diagnosis of ischemia with no obstructive coronary arteries (INOCA) is currently challenging and is based on the demonstration of coronary microcirculatory dysfunction in the absence of CAD ,101. RecCT across the lesion is the strongest predictor of acute coronary syndrome, with a small incremental prognostic value provided by axial plaque and wall shear stress over plaque morphology alone [CT, the FFRCT Planner, allows virtual stenting of coronary stenosis and real-time prediction of post-angioplasty FFR, which could affect the patient selection and procedural planning [Coronary CT Angiography is expected to improve the diagnosis and management of patients with CCS, thanks to the evolution of CFD analytics, advances in hardware, and quantitative CT analysis. Besides vessel-related ischemia, CFD allows the evaluation of hemodynamic forces acting on coronary plaques, which could be related to plaque rupture and thus to the risk of developing acute coronary syndromes (ACS). The EMERALD trial has demonstrated that delta FFRgy alone . A novelplanning . Plaque planning . The derplanning ,107. Allplanning ,109,110.Non-invasive multimodality imaging in chronic coronary syndrome offers a comprehensive anatomic and functional assessment through direct visualization of coronary arteries and a precise quantification of myocardial ischemia or viability. Furthermore, modern techniques can now accurately evaluate functionally coronary microcirculation and diagnose coronary microvascular dysfunction (CMD) ,101.According to the 2019 ESC Guidelines for Coronary Chronic syndromes revascularization is indicated whenever significant stenosis or inducible ischemia are demonstrated at imaging techniques .Both anatomic and functional imaging techniques have strengths and limitations: ESC guidelines recommend CCTA as the initial diagnostic test in patients with a low-to-intermediate clinical probability of CAD due to its high negative predictive value. On the other hand, in patients with an intermediate-high clinical likelihood of CAD a functional ischemia test is preferred as the basis for subsequent coronary angiography . This stOn the other hand, in this trial, CCTA showed superior diagnostic performance compared to stress imaging as it was able to rule out significant CAD in 20% of patients with moderate-to-severe ischemia ,113.Furthermore, the paradigm of myocardial hibernation has been recently challenged by the REVIVED trial, which demonstrated that percutaneous revascularization did not result in a lower incidence of all-cause death or hospitalization for heart failure in patients with severe ischemic left ventricular dysfunction (Left Ventricular Ejection Fraction < 35%) and demonstrable myocardial viability at functional imaging, as compared to optimal medical therapy alone .Notwithstanding the growing relevance of anatomical imaging, some aspects should be considered. In these trials, ischemia is predominantly demonstrated through low specificity and sensitivity techniques such as treadmill tests: it could be argued that ischemia could significantly affect patients’ prognosis when assessed by more sophisticated functional tests, as suggested in patients with angina and non-obstructive coronary arteries . RecentlFunctional non-invasive imaging is essential in some subcategories. In fact, patients with suspected CAD and valvular diseases should undergo stress echocardiography for the assessment of ischemia and the effective hemodynamic impact of valvulopathy . On the Recent guidelines still recommend both functional and anatomical imaging in patients with suspected CAD based on their clinical likelihood. Both pathways offer complementary information for the global clinical diagnosis and subsequent management of suspected CAD ,120.In conclusion, although the most recent evidence hints towards anatomical imaging, it has to be outlined that a global assessment of the patient is often necessary and that functional imaging offers valuable information pivotal to the further therapeutic pathway. Non-invasive imaging methods for the diagnosis of CAD have distinct characteristics; the patient’s cardiovascular risk assessment and pre-test probability should guide the choice of the best method.Cardiologists and radiologists should therefore be aware of the strengths and weaknesses of these imaging techniques in order to choose the diagnostic pathway that tailors properly to the specific patient . Future


Pseudomonas exotoxin A. We also discuss the challenges and limitations of these studies that should be addressed before bacterial toxin-based drug delivery systems can become a viable new generation of drug delivery approaches in clinical translation.Recent advances in targeted cancer therapy hold great promise for both research and clinical applications and push the boundaries in finding new treatments for various currently incurable cancers. However, these therapies require specific cell-targeting mechanisms for the efficient delivery of drug cargo across the cell membrane to reach intracellular targets and avoid diffusion to unwanted tissues. Traditional drug delivery systems suffer from a limited ability to travel across the barriers posed by cell membranes and, therefore, there is a need for high doses, which are associated with adverse reactions and safety concerns. Bacterial toxins have evolved naturally to specifically target cell subtypes via their receptor binding module, penetrating the cell membrane efficiently through the membrane translocation process and then successfully delivering the toxic cargo into the host cytosol. They have, thus, been harnessed for the delivery of various drugs. In this review, we focus on bacterial toxin translocation mechanisms and recent progress in the targeted delivery systems of cancer therapy drugs that have been inspired by the receptor binding and membrane translocation processes of the anthrax toxin protective antigen, diphtheria toxin, and  Bacterial toxins are virulence factors that harm specific host cells by inhibiting cell growth and inducing cell death to favor bacterial infections that cause diseases in humans and animals ,2,3. ManPseudomonas exotoxin A and the related cancer-targeting immunotoxins that are inspired by their receptor binding and membrane translocation processes.Cancer is one of the leading causes of human death worldwide each year and is characterized by abnormal growth and uncontrollable expansion of cells. Despite great improvements in the treatment of cancer, it is still one of the top diseases that threaten human health . It is sBacillus anthracis and is the causative agent of the severe disease called anthrax. It is a binary toxin that consists of the receptor-binding and translocation machinery protective antigen (PA) plus enzymatic executor factors, which are referred to as the lethal factor (LF) and edema factor (EF)   20]. Th. ThBacilnd edema .As the membrane translocation module of the anthrax toxin, PA mediates the delivery of LF and EF through the membrane barrier into the host cytosol. LF and EF bind to the oligomeric HA63 pre-channel, forming the “flowers-in-vase” conformation, where the flowers correspond to the LF or EF cargo and the vase corresponds to the oligomeric HA a 27]. T. T27]. T19F NMR study, with the site-specific labeling of the Phe427 residues with p-fluorophenylalanine (pF-Phe427), shows that pF-Phe427 is intrinsically dynamic in the pre-channel state and even more dynamic in the channel state. Such dynamic behavior of the Φ clamp could provide flexibility and room for unfolded polypeptide chain movement during cargo translocation . As. As75]. otherapy . Moxetumotherapy ,78. Besiotherapy ,80,81.Intracellular proteins and signaling pathways represent vast drug targets, yet the cell membrane is a formidable barrier that prevents drugs from reaching their intracellular targets. Various drug delivery approaches are now being developed and optimized to overcome this challenge, including adeno-associated virus vectors, lipid nanoparticles, toxin proteins, endosymbiotic bacterial extracellular contractile injection systems (eCISs), and homologs of capsid protein-based platforms ,86,87. AA second problem of current bacterial toxin-based targeted delivery systems is the low efficiency of translocation during transmembrane cargo delivery. Currently, we know few details about the translocation of most bacterial toxins due to their dynamic nature, drastic structural rearrangements, as well as the involvement of the lipid bilayer environment. This highlights the need to study these mechanisms further.Another problem of the current bacterial toxin-based delivery systems is the immune clearance of the drug. Because bacterial toxins are exogenous antigens, the immune systems of patients can recognize the toxin and neutralize it before it enters the targeting cells, which can significantly reduce the efficacy of these immunotoxins. Even though various mutants have been designed to reduce immunogenicity based on the study of the B cell and T cell epitopes as well as human neutralizing antibodies, advances in our understanding of immunology could help to design de-immunogenized versions of the bacterial toxins so that they have less clearance by anti-drug antibodies ,90,91,92Capillary leak syndrome is one of the leading adverse effects of immunotoxin therapeutics. Although it can be partially controlled by proper medical management, it is still the dominant dose-limiting factor of ITs ,88. CapiAnother major hurdle for IT-based drug delivery is the relatively low translocation efficiency across cellular membranes, as a significant portion of toxin molecules fail to reach the cytosol . A mechaThe current ITs mainly utilize native toxic cargo to achieve cancer cell killing. Due to the highly modular nature of ITs, it is relatively easy to replace native toxic cargoes with other cargoes to finetune the intracellular pathways and cell-killing effects . Phage-aSince bacterial toxin-based targeted delivery systems can specifically target cancer cells and kill them, such systems, with new antigenic targets, optimized translocation domains, fine-tuned toxic cargoes, and reduced off-target toxicity and immunogenicity, hold great promise to push the boundaries in developing novel treatments of cancers that remain incurable. The combination of immunotoxins with chimeric antigen receptor T cells (CAR-T), immune checkpoint blockade therapy, as well as anticancer nanoparticles can also create novel treatment opportunities for synergistic and superior anticancer outcomes ,99,100.