Endothelial dysfunction and persistent inflammation in severe post-COVID-19 patients: implications for gas exchange.

BACKGROUND: Understanding the enduring respiratory consequences of severe COVID-19 is crucial for comprehensive patient care. This study aims to evaluate the impact of post-COVID conditions on respiratory sequelae of severe acute respiratory distress syndrome (ARDS). METHODS: We examined 88 survivors of COVID-19-associated severe ARDS six months post-intensive care unit (ICU) discharge. Assessments included clinical and functional evaluation as well as plasma biomarkers of endothelial dysfunction, inflammation, and viral response. Additionally, an in vitro model using human umbilical vein endothelial cells (HUVECs) explored the direct impact of post-COVID plasma on endothelial function. RESULTS: Post-COVID patients with impaired gas exchange demonstrated persistent endothelial inflammation marked by elevated ICAM-1, IL-8, CCL-2, and ET-1 plasma levels. Concurrently, systemic inflammation, evidenced by NLRP3 overexpression and elevated levels of IL-6, sCD40-L, and C-reactive protein, was associated with endothelial dysfunction biomarkers and increased in post-COVID patients with impaired gas exchange. T-cell activation, reflected in CD69 expression, and persistently elevated levels of interferon-ß (IFN-ß) further contributed to sustained inflammation. The in vitro model confirmed that patient plasma, with altered levels of sCD40-L and IFN-ß proteins, has the capacity to alter endothelial function. CONCLUSIONS: Six months post-ICU discharge, survivors of COVID-19-associated ARDS exhibited sustained elevation in endothelial dysfunction biomarkers, correlating with the severity of impaired gas exchange. NLRP3 inflammasome activity and persistent T-cell activation indicate on going inflammation contributing to persistent endothelial dysfunction, potentially intensified by sustained viral immune response.

SARS-CoV-2 S protein activates NLRP3 inflammasome and deregulates coagulation factors in endothelial and immune cells.

BACKGROUND: Hyperinflammation, hypercoagulation and endothelial injury are major findings in acute and post-COVID-19. The SARS-CoV-2 S protein has been detected as an isolated element in human tissues reservoirs and is the main product of mRNA COVID-19 vaccines. We investigated whether the S protein alone triggers pro-inflammatory and pro-coagulant responses in primary cultures of two cell types deeply affected by SARS-CoV-2, such are monocytes and endothelial cells. METHODS: In human umbilical vein endothelial cells (HUVEC) and monocytes, the components of NF-κB and the NLRP3 inflammasome system, as well as coagulation regulators, were assessed by qRT-PCR, Western blot, flow cytometry, or indirect immunofluorescence. RESULTS: S protein activated NF-κB, promoted pro-inflammatory cytokines release, and triggered the priming and activation of the NLRP3 inflammasome system resulting in mature IL-1ß formation in both cell types. This was paralleled by enhanced production of coagulation factors such as von Willebrand factor (vWF), factor VIII or tissue factor, that was mediated, at least in part, by IL-1ß. Additionally, S protein failed to enhance ADAMTS-13 levels to counteract the pro-coagulant activity of vWF multimers. Monocytes and HUVEC barely expressed angiotensin-converting enzyme-2. Pharmacological approaches and gene silencing showed that TLR4 receptors mediated the effects of S protein in monocytes, but not in HUVEC. CONCLUSION: S protein behaves both as a pro-inflammatory and pro-coagulant stimulus in human monocytes and endothelial cells. Interfering with the receptors or signaling pathways evoked by the S protein may help preventing immune and vascular complications driven by such an isolated viral element. Video Abstract.

Indications of Helicobacter pylori Eradication Treatment and Its Influence on Prescriptions and Effectiveness (Hp-EuReg).

BACKGROUND: The influence of indications for Helicobacter pylori investigation on prescriptions and effectiveness is unknown. The aim of the study was to assess the impact of indications for H. pylori investigation on prescriptions, effectiveness, compliance, and tolerance. METHODS: International, prospective, non-interventional registry of the management of H. pylori infection by European gastroenterologists (Hp-EuReg). Treatment-näive patients registered from 2013 to 2023 at e-CRF AEG-REDCap were analyzed. The effectiveness was assessed by modified intention-to-treat analysis. RESULTS: Overall, 53,636 treatment-naïve cases from 34 countries were included. Most frequent indications were: dyspepsia with normal endoscopy (49%), non-investigated dyspepsia (20%), duodenal ulcer (11%), gastric ulcer (7.7%), and gastroesophageal reflux disease (GERD) (2.6%). Therapy effectiveness varied by indication: duodenal ulcer (91%), gastric ulcer (90%), preneoplastic lesions (90%), dyspepsia with normal endoscopy (89%), GERD (88%), and non-investigated dyspepsia (87%). Bismuth-metronidazole-tetracycline and clarithromycin-amoxicillin-bismuth quadruple therapies achieved 90% effectiveness in all indications except GERD. Concomitant clarithromycin-amoxicillin-tinidazole/metronidazole reached 90% cure rates except in patients with non-investigated dyspepsia; whereas sequential clarithromycin-amoxicillin-tinidazole/metronidazole proved optimal (≥90%) in patients with gastric ulcer only. Adverse events were higher in patients treated for dyspepsia with normal endoscopy and duodenal ulcer compared with the remaining indications (23% and 28%, p < 0.001). Therapeutic compliance was higher in patients with duodenal ulcer and preneoplastic lesions (98% and 99%, p < 0.001). CONCLUSION: In Europe, patients with gastric or duodenal ulcers and preneoplastic lesions showed higher H. pylori treatment effectiveness. Bismuth and non-bismuth quadruple therapies achieved optimal results in almost all indications. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02328131.

Inflammasome activation mediated by oxidised low-density lipoprotein in patients with sleep apnoea and early subclinical atherosclerosis.

BACKGROUND: Atherosclerosis is a common comorbidity of obstructive sleep apnoea (OSA) patients, caused by the interaction of dyslipidaemia and systemic inflammation. The OSA pro-inflammatory response is mediated by NLRP3 inflammasome activation, which requires a priming signal mediated by intermittent hypoxia (IH) and an activation signal provided by soluble stimulus present in plasma. Our objectives were to study oxidised low-density lipoprotein (oxLDL) expression in OSA patients with or without early subclinical atherosclerosis (eSA) as well as its contribution to NLRP3 activation and tissue factor (TF) release. METHODS: We analysed oxLDL, key components of the NLRP3 inflammasome cascade and TF in plasma and monocytes from OSA patients and non-apnoeic subjects, with or without eSA as determined by increased carotid intima-media thickness without the appearance of atherosclerotic plaques. The oxLDL contribution to NLRP3 inflammasome activation was assessed using in vitro models. RESULTS: High levels of oxLDL were identified in plasma from OSA patients, particularly in those with eSA, as well as an overexpression of NLRP3 cascade components and TF. Furthermore, in vitro models showed that both oxLDL and plasma from OSA patients with eSA act synergistically with IH as a priming and activation signal of NLRP3 that enhances the inflammatory response, pyroptosis and TF release. CONCLUSIONS: OSA patients with eSA exhibit NLRP3 activation by IH and the presence of oxLDL capable of releasing TF, constituting a pathway for the interaction between dyslipidaemia and systemic inflammation in the development of atherosclerotic lesions.

PLK1 regulates centrosome migration and spindle dynamics in male mouse meiosis.

Cell division requires the regulation of karyokinesis and cytokinesis, which includes an essential role of the achromatic spindle. Although the functions of centrosomes are well characterised in somatic cells, their role during vertebrate spermatogenesis remains elusive. We have studied the dynamics of the meiotic centrosomes in male mouse during both meiotic divisions. Results show that meiotic centrosomes duplicate twice: first duplication occurs in the leptotene/zygotene transition, while the second occurs in interkinesis. The maturation of duplicated centrosomes during the early stages of prophase I and II are followed by their separation and migration to opposite poles to form bipolar spindles I and II. The study of the genetic mouse model Plk1(Δ/Δ) indicates a central role of Polo-like kinase 1 in pericentriolar matrix assembly, in centrosome maturation and migration, and in the formation of the bipolar spindles during spermatogenesis. In addition, in vitro inhibition of Polo-like kinase 1 and Aurora A in organotypic cultures of seminiferous tubules points out to a prominent role of both kinases in the regulation of the formation of meiotic bipolar spindles.

Inflammasome Activation: A Keystone of Proinflammatory Response in Obstructive Sleep Apnea.

Rationale: As the mechanism that links obstructive sleep apnea (OSA) with the regulation of inflammatory response is not well known, it is important to understand the inflammasome activation, mainly of NLRP3 (nucleotide-binding oligomerization domain-like receptor 3). Objectives: To assess the NLRP3 activity in patients with severe OSA and to identify its role in the systemic inflammatory response of patients with OSA. Methods: We analyzed the NLRP3 activity as well as key components of the inflammasome cascade, such as adaptor molecule apoptosis-associated speck-like protein, caspase-1, Gasdermin D, IL-1ß, IL-18, and tissue factor, in monocytes and plasma from patients with severe OSA and control subjects without sleep apnea. We explored the association of the different key markers with inflammatory comorbidities. Measurements and Main Results: Monocytes from patients with severe OSA presented higher NLRP3 activity than those from control subjects, which directly correlated with the apnea-hypopnea index and hypoxemic indices. NLRP3 overactivity triggered inflammatory cytokines (IL-1ß and IL-18) via caspase-1 and increased Gasdermin D, allowing for tissue factor to be released. In vitro models confirmed that monocytes increase NLRP3 signaling under intermittent hypoxia in a hypoxia-inducible factor-1α-dependent manner, and/or in combination with plasma from patients with OSA. Plasma concentrations of tissue factor were higher in patients with OSA with systemic inflammatory comorbidities than in those without them. Conclusions: In patients with severe OSA, NLRP3 activation might be a linking mechanism between intermittent hypoxia and other OSA-induced immediate changes with the development of systemic inflammatory response.

Analysis of the Ischemia-Modified Albumin as a Potential Biomarker for Cardiovascular Damage in Obstructive Sleep Apnea Patients with Acute Coronary Syndrome.

Obstructive sleep apnea (OSA) has been identified as a cardiovascular (CV) risk factor. The potential of OSA promoting the synthesis of CV biomarkers in acute coronary syndrome (ACS) is unknown. Ischemia-modified albumin (IMA) has been identified as a specific CV biomarker. The aim of this study was to evaluate the role of IMA as a potential biomarker for determining the impact of OSA in ACS patients. A total of 925 patients (15.5% women, age: 59 years, body mass index: 28.8 kg/m2) from the ISAACC study (NCT01335087) were included. During hospitalization for ACS, a sleep study for OSA diagnosis was performed and blood samples extraction for IMA determination were obtained. IMA values were significantly higher in severe OSA (median (IQR), 33.7 (17.2-60.3) U/L) and moderate (32.8 (16.9-58.8) U/L) than in mild/no OSA (27.7 (11.8-48.6) U/L) (p = 0.002). IMA levels were very weakly related to apnea-hypopnea index (AHI) as well as hospital and intensive care unit stay, although they only maintained a significant relationship with days of hospital stay after adjusting for sex, age and BMI (ß = 0.410, p = 0.013). The results of the present study would suggest a potentially weaker role of OSA in the synthesis of the CV risk biomarker IMA in patients with ACS than in primary prevention.

SMAD4 Expression in Monocytes as a Potential Biomarker for Atherosclerosis Risk in Patients with Obstructive Sleep Apnea.

Obstructive sleep apnea (OSA) patients are at special risk of suffering atherosclerosis, leading to major cardiovascular diseases. Notably, the transforming growth factor (TGF-ß) plays a crucial role in the development and progression of atherosclerosis. In this context, the central regulator of TGF-ß pathway, SMAD4 (small mother against decapentaplegic homolog 4), has been previously reported to be augmented in OSA patients, which levels were even higher in patients with concomitant cardiometabolic diseases. Here, we analyzed soluble and intracellular SMAD4 levels in plasma and monocytes from OSA patients and non-apneic subjects, with or without early subclinical atherosclerosis (eSA). In addition, we used in vitro and ex vivo models to explore the mechanisms underlying SMAD4 upregulation and release. Our study confirmed elevated sSMAD4 levels in OSA patients and identified that its levels were even higher in those OSA patients with eSA. Moreover, we demonstrated that SMAD4 is overexpressed in OSA monocytes and that intermittent hypoxia contributes to SMAD4 upregulation and release in a process mediated by NLRP3. In conclusion, this study highlights the potential role of sSMAD4 as a biomarker for atherosclerosis risk in OSA patients and provides new insights into the mechanisms underlying its upregulation and release to the extracellular space.

Impact of the COVID-19 pandemic in colorectal cancer diagnosis and presentation.

BACKGROUND AND OBJECTIVE: The COVID-19 pandemic has been associated with a decrease in the colorectal cancer (CRC) incidence, due to the disruption of screening programmes and a downscaling of endoscopic activity. The endpoint of this study is to evaluate if the pandemic has led to a change in CRC diagnostic rate and presentation in our population. METHODS: Multicenter retrospective study of all public hospitals of the Aragon region, attending a population of 1,329,391 inhabitants. We have analyzed all CRC cases detected and endoscopic units workload the year before the pandemic onset (1 March 2019-14 March 2020) and the first year of the COVID-19 pandemic (15 March 2020-28 February 2021). RESULTS: The diagnosis of CRC cases dropped a 38.9% (888 pre-pandemic vs 542 pandemic cases). Also, there were 30.3% less colonoscopies performed (24,860 vs 17,337). During the pandemic, CRC cases were diagnosed in older patients (72.4±12.2 vs 71.2±12.1 years, p=0.021), and had more frequently severe complications at diagnosis (14.6% vs 10.4%, p=0.019). Moreover, most CRC cases were diagnosed in symptomatic patients (81.4%). No significant difference was found in CRC stage at diagnosis, although stage IV was more frequent (20.1% vs 16.1%). Most hospitals reported a lower workload of endoscopic activity. CONCLUSION: CRC diagnostic rate was lower after the onset of the pandemic. CRC was diagnosed in older patients and was more frequently associated with complications. After the onset of the pandemic, the endoscopic units did not reach the workload performed previously.

Empirical rescue treatment of Helicobacter pylori infection in third and subsequent lines: 8-year experience in 2144 patients from the European Registry on H. pylori management (Hp-EuReg).

OBJECTIVE: To evaluate the use, effectiveness and safety of Helicobacter pylori empirical rescue therapy in third and subsequent treatment lines in Europe. DESIGN: International, prospective, non-interventional registry of the clinical practice of European gastroenterologists. Data were collected and quality reviewed until October 2021 at Asociación Española de Gastroenterología-Research Electronic Data Capture. All cases with three or more empirical eradication attempts were assessed for effectiveness by modified intention-to-treat and per-protocol analysis. RESULTS: Overall, 2144 treatments were included: 1519, 439, 145 and 41 cases from third, fourth, fifth and sixth treatment lines, respectively. Sixty different therapies were used; the 15 most frequently prescribed encompassed >90% of cases. Overall effectiveness remained <90% in all therapies. Optimised treatments achieved a higher eradication rate than non-optimised (78% vs 67%, p<0.0001). From 2017 to 2021, only 44% of treatments other than 10-day single-capsule therapy used high proton-pump inhibitor doses and lasted ≥14 days. Quadruple therapy containing metronidazole, tetracycline and bismuth achieved optimal eradication rates only when prescribed as third-line treatment, either as 10-day single-capsule therapy (87%) or as 14-day traditional therapy with tetracycline hydrochloride (95%). Triple amoxicillin-levofloxacin therapy achieved 90% effectiveness in Eastern Europe only or when optimised. The overall incidence of adverse events was 31%. CONCLUSION: Empirical rescue treatment in third and subsequent lines achieved suboptimal effectiveness in most European regions. Only quadruple bismuth-metronidazole-tetracycline (10-day single-capsule or 14-day traditional scheme) and triple amoxicillin-levofloxacin therapies reached acceptable outcomes in some settings. Compliance with empirical therapy optimisation principles is still poor 5 years after clinical practice guidelines update. TRIAL REGISTRATION NUMBER: NCT02328131.

Flexible endoscopy assisted by Ligasure™ for treatment of Zenker's diverticulum: an effective and safe procedure.

BACKGROUND: Flexible endoscopy allows use of the vessel-tissue sealer Ligasure™ (Covidien, Massachusetts, USA) to perform diverticulotomy. Few studies have used this endoscopic approach in the uncommon disorder Zenker's diverticulum. The aim of the present study was to evaluate the effectiveness and safety of flexible endoscopy treatment assisted by Ligasure™. METHODS: The single-center prospective and descriptive study included patients treated by flexible endoscopy using Ligasure™ for resection of Zenker's diverticulum. Consecutive patients were included from March 2009 to April 2018. Patients were censored until the end of follow-up or death. Complications, symptoms before treatment, type of sedation, and number of interventions needed to resolve Zenker's diverticulum were analyzed. Bleeding complications were considered when a case required a second endoscopy. RESULTS: A total of 46 symptomatic patients with Zenker's diverticulum were included in the final analysis (41.3% women, median age of 73.7 ± 11 years). The median follow-up period was 37.21 ± 28 months. Of all cases, 58.7% were considered small (< 3 cm). Solid or semi-solid food-related dysphagia was present in 55.6% of patients previously to the procedure. The technique was successful in a single procedure in 78.3% of cases. However, the success rate increased to 89.1% with a second procedure, and we had a complication rate of 4.3% with this technique. Most patients (79.66%) were managed as out-patients or with short (< 24 h) admission. CONCLUSION: In this large case series, treatment of Zenker's diverticulum based on flexible endoscopy assisted by Ligasure™ was a safe and effective procedure with a high success rate in a few endoscopy sessions and low complication rate.

Management of Helicobacter pylori infection at the primary care level. The implementation of specific counseling improves eradication rates.

BACKGROUND: Management of Helicobacter pylori infection has been expanded from the gastroenterology specialist (GS) to primary care physicians (PCPs), with a large increase in requests for urea breath tests (UBT). Due to the lack of evidence at this level, we evaluated the appropriateness of UBT indications and treatment for H pylori infections between PCPs and GSs and the effect of introducing specific counseling to PCPs. MATERIALS AND METHODS: This was a quasi-experimental study. Phase I included 650 consecutive UBT requested by PCPs (400) and GSs (250). Indications and treatments were classified as appropriate or inappropriate based on national guidelines. Data on eradication rates were also collected. In phase II, 240 UBT and patients' treatment outcomes were analyzed after individually counseling PCPs on both aspects. RESULTS: Of 1049 UBT, inappropriate indications in phase I were significantly higher in tests requested by PCP compared with GS (35.9% vs 7.2%; P < 0.001). Inappropriate treatment regimens were significantly higher for PCPs in phase I (65.8% vs 26.4%; P < 0.001). Consequently, eradication rates were significantly lower in patients treated by PCPs compared with those treated by GS (63.7% vs 81.4%; P = 0.004). A significant increase in adherence to appropriate treatment regimens (75.8% vs 34.2%; P < 0.001) and eradication rates (79.2% vs 63.7%; P = 0.002) were observed in the PCP group after counseling; however, the appropriateness of indications did not improve. CONCLUSIONS: Patients infected with H pylori managed at the primary care level had poorer outcomes. The introduction of specific counseling for PCPs significantly improved treatment management, but not indications.