Exposure to respirable silica contributes to lower airway inflammation in asthmatic horses.

BACKGROUND: Respirable mineral particles can induce lower airway inflammation, but the role they play in asthma of horses is unknown. OBJECTIVES: Respirable mineral particles, particularly respirable silica, are an overlooked determinant of chronic lung inflammation (asthma) in horses. ANIMALS: Twenty-three horses from an equine hospital population: 11 moderately affected (MEA), 7 severely asthmatic (SEA), and 5 control horses free from respiratory clinical signs. METHODS: Prospective observational study. The quantity and quality of mineral particles found in bronchoalveolar lavage fluid (BALF) were characterized, with particular attention to silica content. Polarized light microscopy performed on cytospin slides identified intracellular birefringent particles as silica. Spectrometry-based analysis performed on whole BALF determined total mineral and silica percentage and concentration. Group-related differences in BALF mineral and silica load were investigated as well as associations with BALF cytology. RESULTS: Intracellular birefringent particles were increased in SEA vs MEA (median [interquartile range, IQR]), 12 [7] vs 4 [5] particles/30 high power fields [hpf], respectively; P = .01) and vs controls (4 [2] particles/30 hpf; P = .02). Total mineral concentration in BALF was similar between the groups studied, whereas silica concentration and percentage were increased in SEA vs MEA (1758 [887] particles/mL and 20 [10]% vs 867 [662] particles/mL and 8 [6]%; P = .009 and P = .001) and control group (355 [330] particles/mL and 6 [3]%; P = .0003 and P = .002). Silica load in BALF was associated with BALF neutrophilia in MEA and SEA. CONCLUSIONS AND CLINICAL IMPORTANCE: Respirable silica is associated with neutrophilic lower airway inflammation in horses and might contribute to asthma development.

CharActeristics, sizing anD outcomes of stenotic, tapered, rapHe-type bicuspid aOrtic valves treated with trans-catheter device implantation: Insights the AD HOC registry.

BACKGROUND: Raphe-type bicuspid aortic valve (BAV) is a potential hostile scenario in trans-catheter aortic valve replacement (TAVR) due to pronounced calcium burden, possibly associated with tapered valve configuration. Trans-Catheter heart valve (THV) sizing strategy (annular vs. supra-annular) is controversial in this valve subtype. OBJECTIVES: To describe the phenotypical characteristics of severe, tapered, raphe-type, BAV stenosis undergoing TAVR and to explore safety and efficacy of modern-generation THVs, analysing the impact of annular and supra-annular sizing strategies on short- and mid-terms outcomes. METHODS: This is a retrospective, multicenter registry enrolling consecutive stenotic Sievers type 1 BAV treated with TAVR. Study population was divided into tapered and non-tapered configuration according to MSCT analysis. Matched comparison between annular and supra-annular sizing groups was performed in tapered population. RESULTS: From January 2016 to June 2023, 897 patients were enrolled. Of them, 696 patients displayed a tapered configuration. Of those, 510 received a THV according to annular sizing. After propensity score matching 186 matched pairs were selected. Technical success (96.2 % vs 94.1 %, OR 1.61 [0.61-4.24], p = 0.34), 30-day device success (83.6 % in both groups, OR 1.42 [0.78-2.57], p = 0.25) and 30-day early safety (71.8 % vs 70.5 %, OR 1.07 [0.68-1.68], p = 0.78) were similar between the annular and supra-annular sizing groups; a higher post-TAVR gradient was observed in supra-annular group, although it was only 2 mmHg mean. At mid-term follow-up, the rate of clinical efficacy was 84.7 %. CONCLUSIONS: TAVR with modern-generation devices is safe and effective for tapered raphe-type BAV, showing comparable results for annular and supra-annular sizing strategies.

Emission of 50-kHz ultrasonic vocalizations stimulated by antiparkinsonian dopaminomimetic drugs in hemiparkinsonian rats is associated with neuronal activation in subcortical regions that regulate the affective state.

Dopamine replacement therapy (DRT) of Parkinson's disease (PD) may trigger non-motor complications, some of which affect hedonic homeostatic regulation. Management of iatrogenic alterations in the affective state in PD is unsatisfactory, partly because of the limitations in the experimental models that are used in the preclinical investigation of the neurobiology and therapy of these alterations. In this connection, we recently employed a new experimental approach consisting in measuring the emission of 50-kHz ultrasonic vocalizations (USVs), a marker of positive affect, in hemiparkinsonian rats treated with drugs used in the DRT of PD. To further strengthen our approach, we here evaluated how the acute and repeated (× 5, on alternate days) administration of apomorphine (2 mg/kg, i.p.) or L-3,4-dihydroxyphenilalanine (L-DOPA, 12 mg/kg, i.p.) modified the immunoreactivity for Zif-268, a marker of neuronal activation, in the nucleus accumbens (NAc), caudate-putamen (CPu) and medial prefrontal cortex (mPFC), which are brain regions that regulate emotional states and drugs' affective properties. Acute and repeated treatment with either apomorphine or L-DOPA stimulated the emission of 50-kHz USVs in hemiparkinsonian rats, and this effect was paired with increased Zif-268 immunoreactivity in the NAc and CPu, but not mPFC. These findings indicate that subcortical and cortical regions may differently regulate the emission of 50-kHz USVs in hemiparkinsonian rats treated with dopaminergic drugs used in the DRT of PD. Moreover, they provide further evidence that measuring 50-kHz USV emissions in hemiparkinsonian rats may be a relevant approach to investigate at the preclinical level the affective properties of antiparkinsonian drugs.

Incidence, Predictors, and Outcomes of Paravalvular Regurgitation After TAVR in Sievers Type 1 Bicuspid Aortic Valves.

BACKGROUND: Transcatheter aortic valve replacement (TAVR) in patients with bicuspid aortic valve (BAV) stenosis is technically challenging and is burdened by an increased risk of paravalvular regurgitation (PVR). OBJECTIVES: The aim of this study was to identify the incidence, predictors, and clinical outcomes of PVR after TAVR in Sievers type 1 BAV stenosis. METHODS: Consecutive patients with Sievers type 1 BAV stenosis undergoing TAVR with current-generation transcatheter heart valves (THVs) in 24 international centers were enrolled. PVR was graded as none/trace, mild, moderate, and severe according to echocardiographic criteria. The endpoint of major adverse events (MAEs), defined as a composite of all-cause death, stroke, or hospitalization for heart failure, was assessed at the last available follow-up. RESULTS: A total of 946 patients were enrolled. PVR occurred in 423 patients (44.7%)-mild, moderate, and severe in 387 (40.9%), 32 (3.4%), and 4 (0.4%) patients, respectively. Independent predictors of moderate or severe PVR were a larger virtual raphe ring perimeter (adjusted OR: 1.07; 95% CI: 1.02-1.13), severe annular or left ventricular outflow tract calcification (adjusted OR: 5.21; 95% CI: 1.45-18.77), a self-expanding valve (adjusted OR: 9.01; 95% CI: 2.09-38.86), and intentional supra-annular THV positioning (adjusted OR: 3.31; 95% CI: 1.04-10.54). At a median follow-up of 1.3 years (Q1-Q3: 0.5-2.4 years), moderate or severe PVR was associated with an increased risk of MAEs (adjusted HR: 2.52; 95% CI: 1.24-5.09). CONCLUSIONS: After TAVR with current-generation THVs in Sievers type 1 BAV stenosis, moderate or severe PVR occurred in about 4% of cases and was associated with an increased risk of MAEs during follow-up.

Brain dysfunctions and neurotoxicity induced by psychostimulants in experimental models and humans: an overview of recent findings.

Preclinical and clinical studies indicate that psychostimulants, in addition to having abuse potential, may elicit brain dysfunctions and/or neurotoxic effects. Central toxicity induced by psychostimulants may pose serious health risks since the recreational use of these substances is on the rise among young people and adults. The present review provides an overview of recent research, conducted between 2018 and 2023, focusing on brain dysfunctions and neurotoxic effects elicited in experimental models and humans by amphetamine, cocaine, methamphetamine, 3,4-methylenedioxymethamphetamine, methylphenidate, caffeine, and nicotine. Detailed elucidation of factors and mechanisms that underlie psychostimulant-induced brain dysfunction and neurotoxicity is crucial for understanding the acute and enduring noxious brain effects that may occur in individuals who use psychostimulants for recreational and/or therapeutic purposes.

Divergent Acute and Enduring Changes in 50-kHz Ultrasonic Vocalizations in Rats Repeatedly Treated With Amphetamine and Dopaminergic Antagonists: New Insights on the Role of Dopamine in Calling Behavior.

BACKGROUND: Rats emit 50-kHz ultrasonic vocalizations (USVs) in response to nonpharmacological and pharmacological stimuli, with addictive psychostimulants being the most effective drugs that elicit calling behavior in rats. Earlier investigations found that dopamine D1-like and D2-like receptors modulate the emission of 50-kHz USVs stimulated in rats by the acute administration of addictive psychostimulants. Conversely, information is lacking on how dopamine D1-like and D2-like receptors modulate calling behavior in rats that are repeatedly treated with addictive psychostimulants. METHODS: We evaluated the emission of 50-kHz USVs in rats repeatedly treated (×5 on alternate days) with amphetamine (1 mg/kg, i.p.) either alone or together with (1) SCH 23390 (0.1-1 mg/kg, s.c.), a dopamine D1 receptor antagonist; (2) raclopride (0.3-1 mg/kg, s.c.), a selective dopamine D2 receptor antagonist; or (3) a combination of SCH 23390 and raclopride (0.1 + 0.3 mg/kg, s.c.). Calling behavior of rats was recorded following pharmacological treatment, as well as in response to the presentation of amphetamine-paired cues and to amphetamine challenge (both performed 7 days after treatment discontinuation). RESULTS: Amphetamine-treated rats displayed a sensitized 50-kHz USV emission during repeated treatment, as well as marked calling behavior in response to amphetamine-paired cues and to amphetamine challenge. Antagonism of D1 or D2 receptors either significantly suppressed or attenuated the emission of 50-kHz USVs in amphetamine-treated rats, with a maximal effect after synergistic antagonism of both receptors. CONCLUSIONS: These results shed further light on how dopamine transmission modulates the emission of 50-kHz USVs in rats treated with psychoactive drugs.

Evolving Paradigms in Transcatheter Aortic Valve Replacement: Results from a High-Volume, Single Center Experience.

Given the expanding indications toward younger patients at lower surgical risk, transcatheter aortic valve replacement (TAVR) simplification and streamlining are gaining increasing importance. Patients who underwent TAVR from the year 2015 to 2020 were prospectively enrolled. The patients were divided in time tertiles according to the date of intervention. Data on preprocedural planning, including coronary computed tomography angiography (CCTA), procedures, and outcomes, were compared between the time tertiles. A total of 771 consecutive patients from a single institution were enrolled. We observed a trend toward the use of a fully percutaneous versus surgical approach for the index access, left radial artery versus contralateral femoral artery for the secondary access, and left ventricular pacing on the stiff guidewire versus right ventricular pacing. Immediate device success significantly increased, whereas the length of hospital stay decreased. Overall, approximately 60% of the total study population underwent CCTA instead of coronary angiography, with no adverse events. One-year survival rates significantly improved over time. A simplified TAVR approach was associated with better survival, whereas low baseline functional capacity, preexisting coronary artery disease, renal impairment, periprocedural blood transfusions, and paravalvular leak were related to worse outcomes. In conclusion, our study showed a constant tendency to procedure streamlining and improve procedural success and 1-year outcomes. A strategy based on CCTA allows sparing safely almost half of the preoperative invasive coronary angiography.

Impact of Pacemaker Implantation After Transcatheter Aortic Valve Replacement on Long-Term Survival in Patients With Bicuspid Aortic Valve.

Limited data are available about the impact of permanent pacemaker (PPM) implantation on long-term survival in patients with a bicuspid aortic valve (BAV) and severe aortic stenosis (AS) treated with transcatheter aortic valve replacement (TAVR). We aimed to evaluate the long-term clinical outcomes of patients with BAV with AS who underwent periprocedural PPM implantation after TAVR with a self-expandable prosthesis. Data from patients with BAV and severe AS who underwent TAVR between April 2009 and January 2022 and followed in the framework of the One Hospital ClinicalService-CoreValve Project were collected. Patients were categorized in 2 groups according to PPM implantation after TAVR ("PPM" group) or not ("no PPM" group). The coprimary end points were all-cause death and a composite of cardiac mortality, rehospitalization because of cardiac causes, stroke, and myocardial infarction. Overall, 106 patients were considered (74 in the "no PPM" group and 32 in the "PPM" group). No statistically significant difference was found between the groups in terms of follow-up and baseline characteristics. Patients in the PPM group were more likely to show baseline conduction abnormalities (p = 0.023). Patients in the PPM group were more often treated with older generation prosthesis than those in the no PPM group (28.1% vs 5.4%, respectively, p = 0.013). At 2 years of follow-up, all-cause death in the no PPM and PPM groups occurred in 20.0% and 10.0% of patients, respectively (hazard ratio 0.37, 95% confidence interval 0.08 to 1.67). Similarly, no difference was evident for the composite end point between the 2 groups (no PPM vs PPM: 8 [14.6%] vs 6 [19.3%], hazard ratio 1.67, 95% CI 0.58 to 4.81). In conclusion, patients with severe AS and BAV treated with TAVR complicated by PPM implantation are not exposed to an increased risk of major adverse events at 2 years of follow-up.

Evolutionary modelling indicates that mosquito metabolism shapes the life-history strategies of Plasmodium parasites.

Within-host survival and between-host transmission are key life-history traits of single-celled malaria parasites. Understanding the evolutionary forces that shape these traits is crucial to predict malaria epidemiology, drug resistance, and virulence. However, very little is known about how Plasmodium parasites adapt to their mosquito vectors. Here, we examine the evolution of the time Plasmodium parasites require to develop within the vector (extrinsic incubation period) with an individual-based model of malaria transmission that includes mosquito metabolism. Specifically, we model the metabolic cascade of resource allocation induced by blood-feeding, as well as the influence of multiple blood meals on parasite development. Our model predicts that successful vector-to-human transmission events are rare, and are caused by long-lived mosquitoes. Importantly, our results show that the life-history strategies of malaria parasites depend on the mosquito's metabolic status. In our model, additional resources provided by multiple blood meals lead to selection for parasites with slow or intermediate developmental time. These results challenge the current assumption that evolution favors fast developing parasites to maximize their chances to complete their within-mosquito life cycle. We propose that the long sporogonic cycle observed for Plasmodium is not a constraint but rather an adaptation to increase transmission potential.

Haemodynamic and metabolic phenotyping of patients with aortic stenosis and preserved ejection fraction: A specific phenotype of heart failure with preserved ejection fraction?

AIMS: Degenerative aortic valve stenosis with preserved ejection fraction (ASpEF) and heart failure with preserved ejection fraction (HFpEF) display intriguing similarities. This study aimed to provide a non-invasive, comparative analysis of ASpEF versus HFpEF at rest and during exercise. METHODS AND RESULTS: We prospectively enrolled 148 patients with HFpEF and 150 patients with degenerative moderate-to-severe ASpEF, together with 66 age- and sex-matched healthy controls. All subjects received a comprehensive evaluation at rest and 351/364 (96%) performed a combined cardiopulmonary exercise stress echocardiography test. Patients with ASpEF eligible for transcatheter aortic valve replacement (n = 125) also performed cardiac computed tomography (CT). HFpEF and ASpEF patients showed similar demographic distribution and biohumoral profiles. Most patients with ASpEF (134/150, 89%) had severe high-gradient aortic stenosis; 6/150 (4%) had normal-flow, low-gradient ASpEF, while 10/150 (7%) had low-flow, low-gradient ASpEF. Both patient groups displayed significantly lower peak oxygen consumption (VO2 ), peak cardiac output, and peak arteriovenous oxygen difference compared to controls (all p < 0.01). ASpEF patients showed several extravalvular abnormalities at rest and during exercise, similar to HFpEF (all p < 0.01 vs. controls). Epicardial adipose tissue (EAT) thickness was significantly greater in ASpEF than HFpEF and was inversely correlated with peak VO2 in all groups. In ASpEF, EAT was directly related to echocardiography-derived disease severity and CT-derived aortic valve calcium burden. CONCLUSION: Functional capacity is similarly impaired in ASpEF and HFpEF due to both peripheral and central components. Further investigation is warranted to determine whether extravalvular alterations may affect disease progression and prognosis in ASpEF even after valve intervention, which could support the concept of ASpEF as a specific sub-phenotype of HFpEF.

Outcomes of Patients With Very Severe Aortic Stenosis Treated With Transcatheter Aortic Valve Implantation.

Symptoms of aortic stenosis (AS) are not proportional to its severity and patients with very severe AS (VSAS) remain asymptomatic for a long time. The appropriate time for intervention in patients with VSAS and the effects of transcatheter aortic valve implantation (TAVI) on left ventricular hypertrophy (LVH) remain debated. Our aim was to compare the procedural and 30-day outcomes of TAVI between patients with VSAS and patients with severe AS (SAS) and the changes in LVH. We selected patients with an aortic peak velocity ≥5 m/s (VSAS) and those with aortic peak velocity 4 to 5 m/s (SAS) treated with TAVI. Patients with reduced left ventricular ejection fraction (<45%) were excluded. The primary end point was the incidence of all-cause death at 30 days. The secondary end points included the 30-day incidence of cardiac death, cardiac rehospitalization, and stroke/transient ischemic attack and the changes in LVH from baseline to 30 days. A total of 102 patients in the VSAS group and 535 in the SAS group were included. Patients in the VSAS group had a thicker septal wall (p <0.001) and a higher Agaston score (p <0.001) and calcium volume (p = 0.007). No differences were observed regarding the primary and secondary clinical end points. However, patients with VSAS showed a significantly greater improvement in concentric LVH, although the prevalence of concentric LVH remained higher than in patients with SAS. TAVI in patients with VSAS showed similar procedural and clinical outcomes to patients with SAS and experienced a more pronounced improvement in the prevalence of concentric LVH.

Contemporary European practice in transcatheter aortic valve implantation: results from the 2022 European TAVI Pathway Registry.

Background: A steep rise in the use of transcatheter aortic valve implantation (TAVI) for the management of symptomatic severe aortic stenosis occurred. Minimalist TAVI procedures and streamlined patient pathways within experienced Heart Valve Centres are designed to overcome the challenges of ever-increasing procedural volume. Aims: The 2022 European TAVI Pathway Survey aims to describe contemporary TAVI practice across Europe. Materials and methods: Between October and December 2022, TAVI operators from 32 European countries were invited to complete an online questionnaire regarding their current practice. Results: Responses were available from 147 TAVI centres in 26 countries. In 2021, the participating centres performed a total number of 27,223 TAVI procedures, with a mean of 185 TAVI cases per centre (median 138; IQR 77-194). Treatment strategies are usually (87%) discussed at a dedicated Heart Team meeting. Transfemoral TAVI is performed with local anaesthesia only (33%), with associated conscious sedation (60%), or under general anaesthesia (7%). Primary vascular access is percutaneous transfemoral (99%) with secondary radial access (52%). After uncomplicated TAVI, patients are transferred to a high-, medium-, or low-care unit in 28%, 52%, and 20% of cases, respectively. Time to discharge is day 1 (12%), day 2 (31%), day 3 (29%), or day 4 or more (28%). Conclusion: Reported adoption of minimalist TAVI techniques is common among European TAVI centres, but rates of next-day discharge remain low. This survey highlights the significant progress made in refining TAVI treatment and pathways in recent years and identifies possible areas for further improvement.

Molecular and functional properties of human Plasmodium falciparum CSP C-terminus antibodies.

Human monoclonal antibodies (mAbs) against the central repeat and junction domain of Plasmodium falciparum circumsporozoite protein (PfCSP) have been studied extensively to guide malaria vaccine design compared to antibodies against the PfCSP C terminus. Here, we describe the molecular characteristics and protective potential of 73 germline and mutated human mAbs against the highly immunogenic PfCSP C-terminal domain. Two mAbs recognized linear epitopes in the C-terminal linker with sequence similarity to repeat and junction motifs, whereas all others targeted conformational epitopes in the α-thrombospondin repeat (α-TSR) domain. Specificity for the polymorphic Th2R/Th3R but not the conserved RII+/CS.T3 region in the α-TSR was associated with IGHV3-21/IGVL3-21 or IGLV3-1 gene usage. Although the C terminus specific mAbs showed signs of more efficient affinity maturation and class-switching compared to anti-repeat mAbs, live sporozoite binding and inhibitory activity was limited to a single C-linker reactive mAb with cross-reactivity to the central repeat and junction. The data provide novel insights in the human anti-C-linker and anti-α-TSR antibody response that support exclusion of the PfCSP C terminus from malaria vaccine designs.

Glycosylated nanoparticle-based PfCSP vaccine confers long-lasting antibody responses and sterile protection in mouse malaria model.

The development of an effective and durable vaccine remains a central goal in the fight against malaria. Circumsporozoite protein (CSP) is the major surface protein of sporozoites and the target of the only licensed Plasmodium falciparum (Pf) malaria vaccine, RTS,S/AS01. However, vaccine efficacy is low and short-lived, highlighting the need for a second-generation vaccine with superior efficacy and durability. Here, we report a Helicobacter pylori apoferritin-based nanoparticle immunogen that elicits strong B cell responses against PfCSP epitopes that are targeted by the most potent human monoclonal antibodies. Glycan engineering of the scaffold and fusion of an exogenous T cell epitope enhanced the anti-PfCSP B cell response eliciting strong, long-lived and protective humoral immunity in mice. Our study highlights the power of rational vaccine design to generate a highly efficacious second-generation anti-infective malaria vaccine candidate and provides the basis for its further development.

Withania somnifera influences MDMA-induced hyperthermic, cognitive, neurotoxic and neuroinflammatory effects in mice.

Withania somnifera (WS) is utilized in Ayurvedic medicine owing to its central and peripheral beneficial properties. Several studies have accrued indicating that the recreational amphetamine-related drug (+/-)- 3,4-methylenedioxymethamphetamine (MDMA; Ecstasy) targets the nigrostriatal dopaminergic system in mice, inducing neurodegeneration and gliosis, causing acute hyperthermia and cognitive impairment. This study aimed to investigate the effect of a standardized extract of W. somnifera (WSE) on MDMA-induced neurotoxicity, neuroinflammation, memory impairment and hyperthermia. Mice received a 3-day pretreatment with vehicle or WSE. Thereafter, vehicle- and WSE-pretreated mice were randomly divided into four groups: saline, WSE, MDMA alone, WSE plus MDMA. Body temperature was recorded throughout treatment, and memory performance was assessed by a novel object recognition (NOR) task at the end of treatment. Thereafter, immunohistochemistry was performed to evaluate in the substantia nigra pars compacta (SNc) and striatum the levels of tyrosine hydroxylase (TH), as marker of dopaminergic degeneration, and of glial fibrillary acidic protein (GFAP) and TMEM119, as markers of astrogliosis or microgliosis, respectively. MDMA-treated mice showed a decrease in TH-positive neurons and fibers in the SNc and striatum respectively, an increase in gliosis and body temperature, and a decrease in NOR performance, irrespective of vehicle or WSE pretreatment. Acute WSE plus MDMA counteracted the modifications in TH-positive cells in SNc, GFAP-positive cells in striatum, TMEM in both areas and NOR performance, as compared to MDMA alone, while no differences were observed as compared to saline. Results indicate that WSE acutely administered in combination with MDMA, but not as pretreatment, protects mice against the noxious central effects of MDMA.