Early tooth demineralization may be detectable through spatial analysis of polarized light images as demonstrated in this study. This may also prove useful in the early detection of epithelial tumors that comprise the majority of the cancer burden worldwide.The spatial properties of polarized light images have not been greatly exploited in biomedicine to improve sensitivity to superficial tissue regions; therefore, we investigate the optical sampling depth effects as a function of location in the backscattered polarimetric images.Backscattered linear polarization intensity distributions exhibit four-lobed patterns arising through single-scattering, multiple-scattering, and geometrical effects. These photon pathway dynamics are investigated through experimental imaging of microsphere suspensions along with corroborative computational polarization-sensitive Monte Carlo modeling. The studied sampling depth effects of linear and circular polarization images (explored in a previous study) are then evaluated on normal and demineralized human teeth, which are known to differ in their surface and sub-surface structures.Backscattered linear polarization images exhibit enhanced sensitivity to near-surface properties of media  at specific locations within the four-lobed patterns. This yields improved differentiation of two tooth types when spatially selecting image regions in the direction perpendicular to the incident linear polarization vector. Circular polarimetric imaging also yields improved differentiation through spatial selection of regions close to the site of illumination. Improved sensitivity to superficial tissues is achieved through a combination of these linear and circular polarimetric imaging approaches.Heightened sampling sensitivity to tissue microstructure in the surface/near-surface region of turbid tissue-like media and dental tissue is achieved through a judicious spatial selection of specific regions in the resultant co-linear and cross-circular backscattered polarimetric images. It is found that optimal differentiation is achieved through specific spatial selection of polarimetric image regions using both linearly and circularly polarized light. The encouraging results may prove useful for the detection of early tooth decay, an important pre-requisite for effective intervention.22.1® 3, Princeton Instruments), which output The configuration and detailed description of the polarimetric system can be found in Ref. 2.2Monodispersed polystyrene microspheres  of 2.3Teeth were provided by Dr. Anil Kishen from the University of Toronto School of Dentistry, following standard extraction. Upon visual inspection teeth were considered healthy with an intact enamel surface. Teeth were stored for up to 1 month in ethanol prior to use. Tested teeth included incisors and molars. For artificial induction of demineralization, teeth were oriented “sideways” and submerged halfway in 37% phosphoric acid , the scattered polarization intensity from a given incident polarization state can be calculated. For example, incident right-circularly polarized The scattered circular  a cross-circular setup can be employed (which detects helicity-flipped light) and (2) light that is closer to the region of illumination must be selected, as previously shown in fig. 6 in Ref. ,Co- and cross-images of backscattered linearly polarized light from the polystyrene microsphere suspension were obtained experimentally  and throThe “Another feature of the co-linear images is the detection of the reflection-like orthogonalized light see  whose poClearly, co- and cross-linear images, and the various spatial patterns within them, are dependent on sub-surface photon propagation pathway dynamics. The sampling depth effects of these linear polarization images can be further investigated through analysis of computational modeling statistics, which appear to be reliable as supported by the reasonable agreement between the simulation and experimental images.o-linear  and [Figo-linear  cross-lio-linear . It is eThe oblong shape of the distribution in the co-linear image gives rise to a similarly shaped It must be noted that one could instead simply select the light in the very sharply defined illumination region see  to enablOverall, it is shown that co-linear and cross-circular (helicity-flipped) detection are independent signal channels that are sensitive to reflection-like orthogonalized light. This type of light generally penetrates less deeply than the arc-like pathway light, which is much more prominent in cross-linear and co-circular detection configurations. In addition, certain regions within the co-linear and cross-circular images can be selected to further reduce the sampling depth, namely pixels closer to the illumination region (both images) and pixels along the perpendicular axis (co-linear image).4This reduced-sampling-depth polarimetric approach can be applied to biological tissue to evaluate its potential biomedical utility. We thus employ normal and demineralized teeth as representative tissues that are known to have structurally different surface and sub-surface properties.Polarimetric measurements were made on each tooth to differentiate the normal and acidified sides with a focus on superficial dental layers (enamel), and the differences between the two groups were quantified. ,,–,–,,The outermost layer of teeth, the enamel, consists primarily of enamel prisms surrounded by calcium hydroxyapatite.–,,–Analogous to the phantom study, we may gain some theoretical insight into the orthogonalized light response from teeth from their single-scattering Mie optical properties. The thickness of the human enamel layer is estimated to be To test if co-linear and cross-circular intensities are lower in demineralized teeth, the pixel values from the normal and acidified sides of each tooth were summed over the full image and compared using The spatial selection methods developed in the phantom investigation can be applied to improve this differentiation. Specifically, for circularly polarized light, the pixels within the illumination region are selected for summation, and for linearly polarized light, the pixels along the perpendicular axis within the illumination region are selected for summation. The illumination region encompasses the central pixels within a 3 mm diameter . The width of the perpendicular axis rectangle is taken as 1/2 of the illumination region diameter (1.5 mm). These dimensions were chosen to best capture light along the perpendicular axis direction while avoiding “crosstalk” from the higher-order scattering along the 45 deg axes’ directions; again, the “optimal” dimensions of this region should be further investigated. As shown in –,Another potential method of results analysis is to pair the data points as 5Here, it is demonstrated that optical sensitivity to the superficial regions of tissue phantoms and normal/demineralized teeth can be enhanced through a combination of co-linear and cross-circular polarization detection along with judicious spatial selection of specific regions in the backscattered images. In the circular case, the field closer to the illumination region can be selected to reduce the sampling depth. In the linear case, the axis that is perpendicular to the incident linear polarization vector within an area closer to the illumination region can be selected. These results are supported by (1) experimental and computational modeling evidence using polystyrene microsphere suspensions, and (2) experimental polarimetric measurements on normal and demineralized teeth, which are known to differ in their surface/sub-surface structures.–,,In the future, larger tooth sample sizes should be used to further evaluate the approach for this important clinical problem. This dual-channel polarimetric spatial field selection approach can be combined with other depth-sensitive techniques, such as angular-resolved detection,


MtDNA copy number (CN), a putative noninvasive biomarker of mitochondrial dysfunction, is associated with renal disease. The purpose of this review is to describe studies which measured human blood mtDNA-CN in the context of chronic kidney disease (CKD), and to evaluate its potential as a clinical biomarker of kidney disease.Following on from small scale cross-sectional studies implicating mtDNA-CN changes in diabetic kidney disease, recent large scale population studies provide compelling evidence of the association of mtDNA-CN and risk of renal disease in the general population and poor outcomes in CKD patients.The kidney has high bioenergetic needs, renal cells are rich in mitochondrial content containing 100s to 1000s of mtDNA molecular per cell. MtDNA has emerged as both a potential mediator, and a putative biomarker of renal disease. Damage to mtDNA can result in bioenergetic deficit, and reduced MtDNA levels in the blood have been shown to correlate with CKD. Furthermore, leakage of mtDNA outside of mitochondria into the cytosol/periphery can directly cause inflammation and is implicated in acute kidney injury (AKI). Recent large-scale population studies show the association of mtDNA-CN and renal disease and provide a strong basis for the future evaluation of circulating DNA-CN in longitudinal studies to determine its utility as a clinical biomarker for monitoring renal function. The loss of eGFR over time has some predictive value but is inconsistent, and the prediction of eGFR loss based on clinical and demographic risk factors is poor. The refinement of an individual's CKD progression risk has been partially improved by The Kidney Disease Improving Global Outcomes (KDIGO) classification, which combine eGFR with ACR, and categorizes the risk of CKD progression into four groups  . We showed that when HMCs are grown in diabetic conditions, the high glucose leads to increased ROS and at the same time we observed more than 200% increase in cellular MtDNA, however this MtDNA was damaged, and moreover continued growth in high glucose led to reduced mtDNA-CN, and damaged cellular respiration in parallel with increased ROS [35▪▪]. We also found evidence of similar changes in blood samples taken from diabetes patients with and without diabetic kidney disease [35▪▪].mtDNA is present in all nucleated cells and present in high numbers in cells with high bioenergetic needs such as renal cells. Measurement of mtDNA-CN in blood cells can be viewed as a surrogate for systemic mtDNA levels including in the kidney . The pot35In this section we will review human studies which link aspects of renal function with changes in circulating mtDNA-CN Table .▪▪]. Furthermore, PBMCs from patients with diabetic kidney disease also showed reduced bioenergetic flexibility and increased mtDNA damage [35▪▪], confirming the presence of mitochondrial dysfunction. A recent study that showed the potential functional consequence of blood mtDNA-CN changes in patients with diabetic kidney disease was by Petrica et al.. The authors estimated mtDNA-CN in peripheral blood using 25 high-quality mitochondrial single nucleotide polymorphisms from the Affymetrix 6.0 array in 9058 participants, making this one of the largest studies of mtDNA-CN at this scale which reported a link between incident CKD and mtDNA-CN. The blood samples used were described as buffy coat from which genomic DNA was isolated and hybridized to Affymetrix 6.0 microarrays. Twenty five high quality mtDNA SNPs were identified which were said to not cross hybridize to the NUMTs in the nuclear genome. This allowed the authors to use probe densities which were standardized using a linear model which corrected for DNA quality, quantity, batch effects and GC content to estimate relative mtDNA-CN. 1490 participants developed CKD over a median follow-up of 19.6 years. There was no association with mtDNA-CN and eGFR at baseline, but higher mtDNA-CN associated with lower risk of incident CKD  after adjusting for age, sex, and race. After adjusting for additional risk factors of CKD, including prevalent diabetes, hypertension, C-reactive protein level, and white blood cell count, this association remained significant . The authors suggested that future research should focus on modifiable risk factors that improve mtDNA-CN. Although this study shows an association, the authors did not provide any information on the relationship between the estimated mtDNA-CN using mtDNA SNPS and the corresponding absolute mtDNA-CN [▪▪]. The data generated are arbitrary numbers based on probe densities, the potential use of mtDNA-CN as a biomarker requires the determination of the normal and abnormal values of mtDNA-CN in the population under study to identify potential risk ranges. Nevertheless, the scale of this study provides excellent robust support for both a potential mechanistic role of mtDNA-CN changes in the risk of incident CKD, as well as highlighting the promise of mtDNA-CN as a risk marker.The next key report was a large cohort study showing an association between mtDNA-CN and incident CKD in the Atherosclerosis Risk in Communities Study ▪▪. The amtDNA-CN ▪▪. The d▪▪]. Unlike other large cohort studies which estimated mtDNA-CN, Fazzini et al. used a highly accurate plasmid based real time PCR quantification assay allowing them to determine absolute values of mtDNA-CN, which they reported as between 21.29 and 379.5 per cell for CKD patients at stages G3 or G1-2,A3. They showed a 1.8-fold increase in mortality in patients with the lowest quartile of mtDNA-CN and this effect was independent of renal function and cardiovascular disease. They also showed an increased risk of cardiovascular disease as well as nearly double the risk of hospitalization and infection in the lowest quartile of mtDNA-CN. Their data strongly supports the future use of mtDNA-CN as a clinically useful tool for assessing risk by identifying patients in the lowest quartile and determining whether this can be modified.An excellent study which has gone some way to resolving the question of normal and abnormal ranges came from a well established large cohort of 4812 patients from the German Chronic Kidney Disease (GCKD) study, an ongoing prospective multicentre observational study which enrolled patients under the regular care of nephrologists for whom good clinical information especially in terms of renal function was available ▪▪. Unliket al.[▪▪] who assessed the prospective association of mtDNA-CN with CKD progression. They used 2943 participants from the Chronic Renal Insufficiency Cohort study (CRIC) and estimated mtDNA-CN from probe intensities of mitochondrial single nucleotide polymorphisms. They found that the lowest tertile of estimated mtDNA-CN showed the highest risk of progression, again providing strong support for the use of mtDNA-CN as a risk biomarker. However, they did not determine absolute mtDNA-CN, and as they estimated mtDNA-CN in the serum of the patients, this would represent cell free mtDNA, a different blood fraction from the other studies described in this section.Another study looking at a large CKD cohort was by He et al.▪▪ who aset al., 2023), reduced peripheral blood mtDNA-CN was linked to low GFR (eGFR< 60 mL/min/1.73 m2) in patients with biopsy proven immunoglobulin A nephropathy [As well as the above studies on circulating mtDNA-CN largely related to CKD or renal function, many studies have reported changes in both circulating and urinary mtDNA-CN associated with other renal disorders but which are beyond the scope of the current article. Interestingly, in a recent study (Liu hropathy . UrinaryIn this article, the focus was on evaluating studies which have measured circulating mtDNA-CN in the context of CKD, as well as population studies which found a link with aspects of renal function and changes in mtDNA-CN. The evidence that reduced circulating mtDNA-CN indicates risk of renal function decline as well as poor outcome is increasing, and recent large-scale studies have shown strong negative association between mtDNA-CN and health outcomes in the CKD population. However, apart from a few studies which have measured absolute levels, we still do not have established normal and ‘at risk’ levels of mtDNA-CN. This issue is confounded by studies using different sample types. There is a lack of studies measuring the change in mtDNA-CN over time, this is important to determine whether mtDNA-CN has prognostic value in predicting future loss of renal function. There is a strong argument for undertaking such studies as routine monitoring of mtDNA-CN in the CKD population could provide an additional marker to the existing KDIGO, ACR and eGFR based methods. As a DNA based marker which can be measured accurately using very small volumes of whole blood, as little as 10ul, using qPCR to determine values, the use of mtDNA-CN could provide a fast, accessible, and economical biomarker for clinical use.None.None.There are no conflicts of interest.


Radiation dermatitis is a common side effect of radiotherapy in patients with acute and chronic changes affecting the skin. While acute changes occur within 90 days of radiation exposure, chronic changes manifest thereafter. This paper presents a case of a 70-year-old male with squamous cell carcinoma in situ (SCCIS) on the right zygoma who was treated with superficial radiation therapy (SRT), which resulted in a hypo-pigmented atrophic scar. The scar was successfully treated with a single session of Erbium:YAG laser therapy. The findings highlight the need for improved treatment options for radiation-induced skin changes and demonstrate the efficacy of fractionated laser therapy in addressing SRT-induced dermal atrophy. Radiation dermatitis is a frequent adverse effect of radiotherapy observed in approximately 95% of patients undergoing treatment . The sevDespite the widespread use of radiation therapy in dermatology, there is currently no established standard of care for the treatment of radiation-induced skin changes . Skin moA 70-year-old white male presented to the dermatology clinic in August of 2021 with SCCIS on the right zygoma Figure .The skin effects of radiation therapy are well documented, and their severity is graded on a scale of 1 to 5 by the National Cancer Institute , and platelet-derived growth factor (PDGF) . TGF-B aTypically, most patients delight in the aesthetic results of SRT, especially in well-vascularized areas where healing often occurs with minimal cosmetic imperfections. However, the chronic changes of extensive atrophy and hypopigmentation witnessed in this case are an unusual occurrence post-treatment. The proposed solutions for this patient included the use of fillers, such as poly-L-lactic acid (Sculptra), to stimulate collagen production or, alternatively, the application of fractionated Erbium laser, known for its capacity to induce collagen synthesis through controlled thermal injury. Currently, there is no established standard of care for radiation-induced skin changes. Previous research has suggested that conservative measures, including daily washing with soap and water, and application of a mid-potency steroid like mometasone furoate, along with the use of silver nylon dressings to cover the wound, may be beneficial . PharmacOur case adds to the growing evidence of the efficacy of fractionated laser therapy in treating SRT-induced dermal atrophy. By utilizing the Erbium:YAG laser treatment with settings of 500-micron depth at 11% density and 250 microns around the perimeter, we observed a noticeable improvement in atrophy within a mere four weeks.Radiation dermatitis is a common occurrence in patients undergoing radiotherapy, and it can lead to acute and chronic changes in the skin. Despite the lack of a standardized treatment approach, conservative measures, such as skin hygiene and moisturizing and pharmacologic options, have shown some benefits. This case report emphasizes the successful use of Erbium:YAG laser therapy in treating a hypo-pigmented atrophic scar resulting from SRT. The findings support the growing evidence that fractionated laser therapy holds promise for addressing radiation-induced skin changes, particularly dermal atrophy. Further research and larger studies are needed to establish the optimal protocols and effectiveness of laser therapy in managing radiation-induced skin alterations. Improved treatment options can significantly enhance patients’ quality of life by addressing the aesthetic and functional implications of these skin changes.


Although smoking is a well-recognized causative factor of urothelial bladder cancer and accounts for 50% of cases, less is known about the prognostic significance of smoking on non-muscle invasive bladder cancer (NMIBC) prognosis. This systematic review and meta-analysis aimed to evaluate the effect of smoking on the risk of NMIBC recurrence and progression.We systematically searched Medline, Web of Science and Scopus databases for original articles published before October 2021 regarding the effect of smoking on NMIBC recurrence and progression. Information about smoking status and the number of events or odds ratio or hazard ratio for event-free survival must have been reported to include the study in the analysis. Quality In Prognosis Studies tool was utilized for the risk of bias assessment.P < 0.0001) compared to never smokers. Subgroup analysis of 2967 patients revealed that current smokers were at a 1.24 higher risk of recurrence  compared to former smokers. A meta-analysis of the hazard ratio revealed that smokers are at higher risk of recurrence  and progression  compared to never smokers. Detrimental prognostic effect of smoking on progression, but not for recurrence risk was also noted in the subgroup analysis of high-risk patients  and BCG-treated ones .We selected 64 eligible studies, including 28 617 patients with NMIBC with available data on smoking status. In a meta-analysis of 28 studies with 7885 patients, we found that smokers (current/former) were at higher risk for recurrence (OR = 1.68; 95% CI 1.34–2.09; In conclusion, patients with non-muscle invasive bladder cancer and a history of smoking have a worse prognosis regarding recurrence-free and progression-free survival compared to non-smokers.The online version contains supplementary material available at 10.1007/s00432-022-04464-6. Urothelial bladder cancer (UBC) is ranked as the seventh most common malignancy worldwide in men and seventeenth in women. Smoking is a well-evidenced, strong causative factor responsible for the development of approximately 50% of bladder tumours  and outcomes of radical cystectomy (RC) for muscle-invasive bladder cancer (MIBC) are compromised in smokers  to identify studies published before October 2021. We searched Medline (Pubmed), Scopus and Web of Science databases using the following terms: “ AND (non-muscle invasive bladder cancer OR NMIBC) AND (Risk factors OR Smoking OR smoke OR cigarette OR tobacco)) OR  AND (non-muscle invasive bladder cancer OR NMIBC) AND (Smoking OR smoke OR cigarette OR tobacco))” and “ AND (non-muscle invasive bladder cancer OR NMIBC) AND (Smoking OR smoke OR cigarette OR tobacco)”, respectively.Relevant citations of identified papers were manually searched to retrieve any further studies not found using algorithmic queries. Studies were included only if the information regarding smoking status  and NMIBC recurrence and/or progression risk were available and its association with the risk of recurrence and/or progression in non-muscle invasive bladder cancer. Either the number of events, event rate or odds ratio or hazard ratio for event-free survival must have been reported to include the study in the analysis. Studies in which the odds ratio for recurrence/progression according to the smoking status were available but the number of events were not reported and could not be recalculated were excluded . In the bias evaluation with QUIPS, the following six domains were analyzed: study participation (sampling bias), study attrition (attrition bias), prognostic factor measurement, outcome measurement (ascertainment bias), study confounding, and statistical analysis and reporting  version 5.4. software.Groups of current smokers vs former smokers and former vs never smokers were compared in terms of NMIBC recurrence risk (odds ratio). Recurrence-free survival was compared between current vs never smokers and former vs never smokers (pooled hazard ratio). Groups of smokers (current or former) vs non-smokers (never smokers) were compared in terms of recurrence and progression risk (odds ratio and pooled hazard ratio). Odds ratios supplemented with 95% confidence intervals were generated based on contiguous tables containing raw data with the number of events in smokers/non-smokers or current/former/never smokers. Hazard ratios for time to recurrence or progression were retrieved from studies with respective 95% confidence intervals and the pooled hazard ratio was calculated. Adjusted hazard ratios were preferably extracted whenever available. We summarized the data using a random-effects model. Forest plots with 95% confidence intervals were generated. To assess the heterogeneity we used the Chi-square test for the degrees of freedom evaluation and the We selected 64 eligible studies, including 28,617 patients with non-muscle invasive bladder cancer and reported oncological outcomes according to the smoking status Figs. . Thirty-The characteristics of included studies and patient cohorts are summarized in Table The conducted analyses Figs. , 7, 8, 9I2 = 71%; P < 0.0001) compared to never smokers . Analysis of 9 studies including 2672 patients regarding the progression risk did not reveal an increased risk for smokers vs never smokers  are at higher risk for recurrence  provided exact data on recurrences in the group of current smokers, former smokers and never smokers, respectively. The comparison between the risk of recurrence was also performed between the respective groups: current smokers vs former smokers and current vs never smokers  compared to former smokers and former smokers had an increased risk compared to never .Seventeen studies N = 405 proviMany studies did not provide comprehensive data on recurrence/ progression rates or numbers in the subgroups of smokers and non-smokers, but provided hazard ratios supplemented with 95% confidence interval and those were used for RFS and PFS analysis. Fifty studies were available for analyses of the pooled hazard ratio for recurrence and/or progression.I2 = 77%; P < 0.0001)    compared to never smokers    included six studies and showed that smoking status did not influence RFS    included eight studies and showed that smoking status did not influence RFS  have a worse prognosis than non-smokers diagnosed with NMIBC. Both RFS and PFS are compromised in patients who have ever smoked compared to never smokers. A separate analysis of the recurrence rates confirmed an increased risk of recurrence but not progression in smokers compared to non-smokers.The initial evidence of the smoking impact on bladder cancer prognosis comes from the cohorts treated with neoadjuvant chemotherapy (NAC) and radical cystectomy (RC), in which smoking status increased cancer-specific mortality (CSM) , we failed to validate it in contingency tables evaluating progression risk itself (P = 0.12). The discrepancy between the evidenced risk of compromised PFS (HR) but not increased progression risk (OR) might signalize the bias in the selection of the studies. Significant differences in follow-up time and characteristics of cohorts analyzed in included studies might therefore explain the discrepancy. The extraction of the data for this meta-analysis from studies that did not aim to focus on the smoking effect on prognosis as the main research question and, therefore, did not show comprehensive data on smoking, must be considered as another limitation. Analyses of event-free survival and risk of an event do not lead to the same conclusions and, therefore, presented effects of smoking on progression should be interpreted with caution. Nevertheless, the detrimental effect of smoking on PFS was also observed in the sensitivity analysis  and subgroup analyses- in BCG-treated individuals as well as in the high-risk-only NMIBC cohort. Another issue is the lack of adjustment for other prognostic factors  when calculating recurrence/progression risk (odds ratio), but in the majority of studies providing RFS/PFS assessment, the hazard ratio was adjusted for other confounders. The higher prevalence of aggressive cancer in smokers than in non-smokers . Almost all included studies were retrospective and the majority of them did not focus directly on smoking status and did not address its prognostic value as a main research question. Consequently, smoking status reporting differed between studies Below is the link to the electronic supplementary material.


Nature in March 2023, Fabio Zani and colleagues reported that high concentrations of the zero-calorie artificial sweetener sucralose affected the proliferation and differentiation of T cells toward interferon-γ-producing subsets, with no effect observed for B cells and myeloid cells.1 The publication has raised high hopes in the lay press on a widely available cure for patients suffering from autoimmune diseases.In their research article in 1 Cell type-specific differences in cell membrane lipid composition are suggested by the authors as an explanation for the effect of high concentration sucralose, specifically in T cells. Indeed, lipid rafts compartmentalize signaling molecules in a spatially and temporally dynamic manner, thereby providing a means to selectively and flexibly permit or avoid activation of individual signaling cascades. This principle has been acknowledged to be crucial for T-cell expansion. Several mechanisms by which sucralose might potentially affect lipid raft formation and/or targeting of individual proteins to lipid rafts are conceivable, while keeping in mind the non-stable interaction of sucralose with T-cell membranes.1 More detailed molecular characterization of lipid rafts and functional interaction of proteins therein in the presence of sucralose, also in a concentration-dependent manner, may provide further insight into underlying molecular mechanisms.1 With respect to a potential clinical application in humans, it would be worthwhile to examine whether the membrane composition of T cells is indeed particularly sensitive to sucralose or whether other cell types are similarly affected by sucralose. This includes cells from the myeloid lineage, which are receptive to molecular patterns including glycated metabolites and cell components, and platelets which can be activated by another artificial sweetener, erythritol.2 Inter-individual variations in sucralose plasma levels might then translate into differential cell type-specific effects.Sucralose interfered with T-cell membrane order and limited PLCγ1-dependent induction of intracellular calcium release into the cytoplasm Fig. .1 Cell t1 Despite the experimental nature of data with limited transferability to humans due to differences in immune system function, genetic variability between the species, and high heterogeneity in genetic background and lifestyle in humans . The long-term safety of artificial sweeteners is a recurring concern, with sucralose considered one of the safest.4 Long-term data on sucralose effects on human health when given daily at doses comparable to those used by Zani et al. are not available and will be needed prior to a potential clinical exploitation in patients with autoimmune diseases. Considering potential infection and tumor risk as well as practical issues of palatability, very likely a potential clinical application would constitute in a short-term application limiting acute autoimmune flares rather than a long-term preventive treatment. The observation that sucralose effects appeared to be reversible after washing-out of sucralose would improve the safety profile if replicated in humans on a systemic level.Differences between experimental findings in the current study and previous pre-clinical and clinical reports might also be explained by the extremely high dose of sucralose used by Zani et al.In conclusion, randomized prospective clinical studies are warranted to determine whether the authors’ hypothesis that high doses of sucralose may be beneficial for various conditions arising from unrestrained T-cell activity in humans is more than a “sweet dream”.


Motor learning is defined as an improvement in performance through practice. The ability to learn new motor skills may be particularly challenged in patients with Parkinson’s disease, in whom motor execution is impaired by the disease-defining motor symptoms such as bradykinesia. Subthalamic deep brain stimulation is an effective treatment in advanced Parkinson’s disease, and its beneficial effects on Parkinsonian motor symptoms and motor execution have been widely demonstrated. Much less is known about whether deep brain stimulation directly interacts with motor learning independent of modulation of motor execution. We investigated motor sequence learning in 19 patients with Parkinson’s disease treated with subthalamic deep brain stimulation and 19 age-matched controls. In a cross-over design, patients performed an initial motor sequence training session with active and inactive stimulation, respectively (experiments separated by ≥14 days). Performance was retested after 5 min and after a 6 h consolidation interval with active stimulation. Healthy controls performed a similar experiment once. We further investigated neural correlates underlying stimulation-related effects on motor learning by exploring the association of normative subthalamic deep brain stimulation functional connectivity profiles with stimulation-related differences in performance gains during training. Pausing deep brain stimulation during initial training resulted in the inhibition of performance gains that could have been indicative of learning at the behavioural level. Task performance improved significantly during training with active deep brain stimulation, but did not reach the level of learning dynamics of healthy controls. Importantly, task performance after the 6 h consolidation interval was similar across patients with Parkinson’s disease independent of whether the initial training session had been performed with active or inactive deep brain stimulation. This indicates that early learning and subsequent consolidation were relatively intact despite severe impairments of motor execution during training with inactive deep brain stimulation. Normative connectivity analyses revealed plausible and significant connectivity of volumes of tissue activated by deep brain stimulation with several cortical areas. However, no specific connectivity profiles were associated with stimulation-dependent differences in learning during initial training. Our results show that motor learning in Parkinson’s disease is independent of modulation of motor execution by subthalamic deep brain stimulation. This indicates an important role of the subthalamic nucleus in regulating general motor execution, whereas its role in motor learning appears negligible. Because longer-term outcomes were independent of performance gains during initial training, patients with Parkinson’s disease may not need to wait for an optimal motor state to practice new motor skills. et al. report that motor learning in persons with Parkinson’s disease is independent of modulation of motor execution by subthalamic deep brain stimulation during initial training. This indicates an important role of the subthalamic nucleus in regulating general motor execution, whereas its role in intrinsic motor learning seems negligible.Muehlberg   This is the case in Parkinson’s disease (PD), in which motor execution becomes increasingly impaired with disease progression due to worsening of characteristic motor symptoms such as bradykinesia and rigidity. The disease-defining motor symptoms are caused by the loss of nigro-striatal dopaminergic projections, resulting in a depletion of striatal dopamine.13 Given the striatal dysfunction in PD,15 and the important role of cortico-striatal interactions in initial online learning and offline consolidation,9-12 one would expect PD to impair motor learning. Previous research that primarily investigated early online motor learning yielded inconsistent results regarding whether motor learning is impaired in PD.16-23 Even less is known about whether offline motor memory consolidation is affected by the disease. The scarce evidence, however, indicates that consolidation in PD is comparable to that of age-matched healthy controls both overnight and over the day.25The ability to acquire and refine motor skills is essential to maintaining functional independence throughout life. One approach to investigate the behavioural correlates and neural mechanisms of motor learning is to apply motor sequence-learning paradigms. Typically, in these paradigms, a series of simple movements are ultimately integrated into a coherent unit through practice.27 Despite extensive research demonstrating that DBS improves Parkinsonian motor symptoms, much less is known about the potential effects of DBS on motor learning. A recent study by de Almeida Marcelino et al.28 reported that early motor skill acquisition was impaired in PD (when DBS was inactive) but could be substantially enhanced by DBS almost up to the level of age-matched healthy controls. However, withdrawal of DBS, by design, leads to substantial worsening of PD motor symptoms, which limits motor execution and, consequently, contaminates the range of potential training-induced performance gains. It is thus difficult to disentangle the effects of DBS on motor learning from effects on motor execution during practising. Similar limitations may apply to a smaller sample size study,29 which also reported a relative improvement in motor learning with active DBS compared with learning under inactive DBS across a single training session. It is generally believed that online and offline motor learning processes strongly interact and that motor memory consolidation already starts during practice.30-36 Because consolidation appears to be intact in PD, delayed retesting of motor performance after an offline consolidation interval may represent a more reliable indicator of how much was learned during initial training independent of motor execution at that time.In recent years, subthalamic deep brain stimulation (DBS) has become an established and proven effective treatment for patients with PD suffering from motor complications related to fluctuations in the efficacy of dopaminergic medication.37 In two separate experiments, PD patients performed initial motor sequence learning with active and inactive DBS, respectively. The primary outcome, however, was motor sequence performance after an offline consolidation interval of 6 h. This design, on the one hand, allowed us to separate the effects of DBS on motor learning from those on motor execution. On the other hand, it allowed us to investigate the interaction of DBS with online motor memory formation and subsequent offline consolidation. We also explored normative functional connectivity networks underlying DBS-associated differences in motor learning and Parkinsonian motor symptom improvements. The results provide new insights into motor skill acquisition in PD and the effects of subthalamic DBS on motor learning and motor execution.The current study aimed to address the question of whether subthalamic DBS specifically interacts with motor learning or whether the effects of DBS are limited to the facilitation of motor execution in PD. This distinction is essential as conditions that affect performance do not necessarily have to affect learning.The study protocol was approved by the local Ethics Committee (registration code: 277/20-ek) and was registered in the German Clinical Trials Register .38 exclusion cut-off <18) and no relevant depressive symptoms according to the short version of Beck’s Depression Inventory39 . According to the Edinburgh Handedness Inventory,40 all participants, except one PD patient and two HCs who were classified as ambidextrous, were right-handed. PD motor symptoms were assessed by applying the motor section of the Movement Disorder Society Unified Parkinson’s Disease Rating Scale (MDS-UPDRS-III41).Forty individuals  were recruited for the study between September 2020 and March 2022. PD patients were recruited from the movement disorders outpatient clinic at the Department of Neurology, Leipzig University Medical Center. Age-matched HCs without PD either were spouses of the recruited PD patients or recruited via local announcements. All participants were naive to the motor sequence-learning task. We excluded subjects with a history of alcohol/drug abuse, other neurological diseases than PD, acute psychosis and any severe internal or orthopaedic conditions that could have interfered with task performance. All participating individuals demonstrated no relevant cognitive impairment as assessed by the Montreal Cognitive Assessment , an early retest of motor sequence performance 5 min after termination of the training session (EarlyRT), and a late retest after a further interval of 6 h (LateRT). Experiments differed with respect to the DBS condition during the initial training session. In the DBS-OFF experiment, DBS was switched off 30 min before the onset of the training session, and participants performed the training session under inactive DBS. Immediately after the termination of the training session, DBS was turned back on so that EarlyRT and LateRT were executed under active DBS. In the DBS-ON experiment, DBS remained active all the time. PD motor symptoms (MDS-UPDRS-III) were assessed at baseline, immediately before the training session (pre-Training), and before early (pre-EarlyRT) and late retesting (pre-LateRT). Due to the narrow time window between the end of Training and EarlyRT, assessment of motor symptoms before EarlyRT consisted of only the right upper extremity subscore of the MDS-UPDRS-III (rUES), which was condensed to the items that are specifically relevant for right-hand function . No modifications were made to the regular dopaminergic PD medication for either one of the experiments. Healthy controls performed only one but otherwise identical experiment . Particiet al.1 In each experiment, participants were asked to execute either one of two equally difficult five-element finger-tapping sequences  on a four-button keyboard with the right hand. Before the onset of the actual training session, participants had to correctly reproduce the assigned sequence three times in a row to verify explicit knowledge. The initial training session and the LateRT comprised 14 blocks of successive sequence execution, while the EarlyRT consisted of only 4 blocks. A green visual cue displayed on a computer monitor in front of the participants indicated the onset of a training block, while a stop signal  indicated the onset of a 25 s rest period. Participants were instructed to perform the finger-tapping sequence as fast as possible, while making as few errors as possible. Unbeknownst to the participants, each block of task execution was terminated after 60 button presses, which results in a maximum number of 12 correctly performed sequences per block. This design ensures that all participants perform the same number of finger movements regardless of task performance speed. Participants were instructed to refrain from mentally or physically practising the task in the consolidation period between the early and LateRT and to go about their regular daily business. During the ongoing study, we additionally introduced a visual analogue scale  to assess subjective fatigue of the right hand before EarlyRT in the DBS-OFF and DBS-ON experiments (n = 11 patients).Motor sequence learning was assessed using a modified version of the explicit sequential finger-tapping task introduced by Karni 42Custom MATLAB®  scripts were used to record the timing of button presses on a customized gaming keyboard and to extract measures of speed performance and accuracy. Performance in terms of speed was defined as the average time (seconds) it took to execute a correct sequence within a given block of task execution . Accuracy was defined as the ratio of the number of correctly performed sequences per block to the maximum number of sequences per block (i.e. 12). As a primary measure of task performance, we applied a performance index (PI) that incorporates both equally important components of task performance as both speed and accuracy were modulated by DBS (see Results) and to take into account potential interindividual differences with respect to the strategy to improve task performance :x is the block no., CSD(x)is the mean correct sequence duration in block x, and ACC(x) is the number of correctly performed sequences divided by 12 (i.e. the number of sequences per block) in block x.where t-tests (as applicable) were used for a follow-up analysis in case rmANOVA revealed a significant interaction of within- or between-subject factors. Learning across initial training was assessed as the difference between the end-of-training performance  and baseline task performance in the first block of the training session . Offline performance changes (i.e. consolidation) between the EarlyRT and LateRT were assessed as the difference between task performance at the beginning of the LateRT (PI of the first block) and the average performance across the four blocks of EarlyRT. We chose to use only the first block of LateRT for calculating offline performance changes to avoid confounding the consolidation measure with additional online learning. Associations of Parkinsonian motor symptoms and task performance gains were assessed with Pearson’s correlation coefficient . All statistical analyses were performed with SPSS® 27  and MATLAB . For all statistical tests, the alpha level was set to P< 0.05. rmANOVAs were checked for violation of sphericity and degrees of freedom, and P-values were corrected accordingly (Greenhouse-Geisser correction). For handling of missing data, see Changes in task performance (PI/speed/accuracy) across blocks of practice and changes in the MDS-UPDRS-III/rUES values across time were explored by repeated measures ANOVAs. Follow-up rmANOVAs and paired-sample or independent-sample two-sided 43), the Lead-DBS toolbox (v2.5.344), and SPM12 . Plausibility of the electrode reconstruction procedure was validated by a sweet-spot analysis using the VTAs (left DBS lead) and the DBS-associated differences of task-relevant motor symptoms (rUES scores). We then used publicly available resting-state functional MRI data from healthy controls included in the human connectome project to estimate VTA-to-whole-brain connectivity. In addition, R-maps were calculated as the voxel-wise correlation of VTA-to-voxel-connectivity with DBS-associated differences in performance gains during training and DBS-induced improvement of Parkinsonian motor symptoms to identify DBS-connectivity profiles that are associated with these metrics  were estimated from individual preoperative MRI scans and postoperative computed tomography scans using 3DSlicer . Additionally, PD patients differed significantly from HCs in terms of depressive symptoms , and there was a trend for lower MoCA scores in PD patients . However, for both metrics, scores did not reach the threshold that would indicate mild depression or manifest dementia in either group.Demographic and clinical characteristics of PD patients and HCs included in the final analysis are provided in P = 0.831) demonstrating a similar baseline burden of PD motor symptoms at the beginning of both experiments. A rmANOVA conducted on the MDS-UPDRS-III scores with the main factors DBS (DBS-ON/DBS-OFF) and Time (Baseline/pre-Training) revealed a significant interaction of DBS × Time . This was driven by almost doubled MDS-UPDRS-III scores in the pre-Training assessment compared with baseline in the DBS-OFF experiment (41.9 ± 12.7), while motor symptom severity remained unchanged in the DBS-ON experiment  = 15.041, P < 0.001]. This interaction was driven by the observation that turning DBS off led to increased (i.e. worse) rUES values in the pre-Training assessment (8.5 ± 2.7) that differed significantly from the pre-Training rUES values under active DBS , whereas the rUES did not significantly differ at any other time point .Baseline MDS-UPDRS-III averaged 22.7 ± 8.4 in the DBS-ON experiment and 22.9 ± 8.1 in the DBS-OFF experiment  = 6.184, P = 0.023] that was driven by faster sequence execution in the DBS-ON condition  compared with the DBS-OFF condition (5.2 ± 4.2 s). Accuracy was modulated by DBS in a similar direction as mean accuracy across the initial training session amounted to 0.86 ± 0.14 in the DBS-ON experiment and 0.74 ± 0.28 in the DBS-OFF experiment , a significant main effect of Block , and a significant interaction of DBS × Block . As expected, the significant main effect of DBS was driven by impaired overall task performance across blocks of training in the DBS-OFF condition  compared with the DBS-ON condition  = 5.733, P< 0.001], while there was no significant change of task performance across the training session  in the DBS-OFF condition . The significant effect of Block in the DBS-ON condition was driven by an average individual PI improvement across training of 3.87 ± 4.53 (difference of PI at EOT minus BOT), while PI improved by only 0.62 ± 2.79 during training in the DBS-OFF condition  = 31.908, P < 0.001], a significant main effect of Group  was found, driven by significantly higher PI values averaged across training in HCs (17.39 ± 9.69) compared with PD patients under active DBS (7.33 ± 8.62). More importantly, different dynamics of performance gains in DBS-ON and HCs were indicated by a significant interaction of Group × Block  and interaction of Group × Block  generated by the overall low task performance and lack of performance improvements across training in PD patients under inactive DBS compared with HCs. Collectively, the above findings indicate that suspending subthalamic DBS inhibits the ability of PD patients to improve task performance across the training session. Active DBS, however, restored the motor learning abilities of PD patients leading to increased training-induced performance gains, yet not up to the level of age-matched HCs.Training performance in the DBS-ON and DBS-OFF experiments was compared with age-matched HCs by applying mixed rmANOVAs to the PI values with the between-subject factor Group  and the within-subject factor Block separately for DBS-ON and DBS-OFF. In addition to a significant main effect of Block  that was driven by impaired task performance in the DBS-OFF experiment compared with the DBS-ON experiment . There was a significant effect of Block , but no significant interaction of DBS × Block , indicating similar learning dynamics during EarlyRT (P< 0.001), but no significant interaction of Group × Block in both cases (both P ≥ 0.860). Collectively, this demonstrates that after DBS was turned back on in the DBS-OFF experiment, the capacity to learn across EarlyRT did not differ from that in the DBS-ON experiment and from that of HCs.RmANOVA conducted on the four blocks of EarlyRT revealed a significant main effect of DBS , but no significant effect of the DBS condition during Training , and no significant interaction of both factors , indicating a similar level of overall task performance and similar learning across LateRT in the DBS-OFF and DBS-ON experiments (P < 0.001).RmANOVA on PI values across blocks of the LateRT session revealed a significant effect of Block  and a significant effect of Session , there was a trend for a significant interaction of DBS × Session , suggesting that offline performance gains differed between the DBS-ON and DBS-OFF experiments. This was driven by the fact that performance decreased from Early RT  to the first block of LateRT  in the DBS-ON experiment, while task performance remained stable in the DBS-OFF experiment . HCs showed a similar pattern of consolidation as PD patients in the DBS-ON experiment in that task performance decreased significantly offline . Accordingly, comparison of consolidation between HCs and PD patients in the DBS-ON and DBS-OFF experiments by separate rmANOVAs revealed a significant main effect of Group in both cases (both P< 0.001), while a significant interaction of Group × Session was only found for the comparison of HCs and DBS-OFF . This supports that inactive DBS-associated inhibition of performance gains across training was later compensated during offline consolidation.Consolidation across the 6 h offline interval was explored by applying a rmANOVA with the factors DBS and Session (EarlyRT/LateRT) to the average PI across the four blocks of EarlyRT and the PI at the onset of LateRT (first block). In addition to a significant effect of DBS [P = 0.005, n = 38), indicating that a worse motor state was associated with impaired performance gains during training , this correlation was lost when DBS was turned off , the magnitude of performance gains during training was negatively associated with pre-Training task-relevant Parkinsonian motor symptoms  which correspond well with previously published coordinates.± 1.1 mm . This inP ≥ 0.682, DBS-induced motor symptom improvement P ≥ 0.997 for every cluster). We then calculated R-maps to further explore VTA-connectivity associated with DBS-related differences in performance gains and DBS-induced improvement of Parkinsonian motor symptoms. The unthresholded R-maps exhibited both positive and negative correlations, albeit in partly different locations. DBS-associated differences in performance gains during training had positive correlations to VTA-connectivity to cerebellar, frontal and parietotemporal regions particularly in the left brain, while negative correlations were found with the central region. DBS-induced improvement of task-relevant motor symptoms was correlated with positive VTA-connectivity to bilateral parietotemporal and frontal areas, while negative connectivity to central regions was also correlated with improvements in rUES. The pattern was retained, although attenuated, when masking the R-maps with the map of voxels whose connectivity to the VTAs was significant . Following the approach by de Almeida Marcelino et al.,28 the correlation between the behavioural metrics and the individual similarities of connectivity maps to the R-map for the same metric was significant for DBS-associated differences in performance gains during training  and DBS-associated motor symptom improvement . However, as R-maps are built upon the metric with which they are correlated, this result arises directly from the way R-maps are constructed and, therefore, does not generate new insights. We, additionally, used leave-one-out cross-validation to predict DBS-induced differences in performance gains during training and DBS-induced motor symptom improvement from the similarity of individual connectivity maps to the R-maps generated by leaving out the patient whose behavioural metric was to be predicted. We found that neither DBS-associated performance gains during training nor DBS-induced improvements in Parkinsonian motor symptoms could be predicted using this approach .In the normative resting-state functional MRI analysis, we found significant positive VTA-to-whole-brain connectivity to bilateral basal ganglia, insular, frontal, perisylvic and precentral regions, while negative connectivity was found to cerebellar and occipital areas . We furtnificant . The simThe current study investigated the effects of subthalamic DBS on motor sequence learning during initial training and subsequent offline consolidation in PD. We found that task performance gains were inhibited during initial training with inactive DBS as expected. While performance improved significantly during training under active DBS, patients with PD did not reach the level of task performance and learning dynamics of age-matched HCs. Importantly, motor sequence performance after an offline consolidation interval of 6 h was similar in PD patients regardless of whether the initial training session had been performed under active or inactive DBS. This could indicate that despite severe impairments of training-induced improvements in motor sequence execution under inactive DBS, formation of motor sequence memory traces to be later consolidated offline may still be intact. Interestingly, inhibition of performance gains during initial training in PD patients under inactive DBS was compensated during offline motor memory consolidation, while motor performance decreased across the offline consolidation interval in both age-matched HCs and PD patients when initial training was performed under active DBS.29 However, withdrawal of DBS, by design, results in clinically relevant worsening of Parkinsonian motor symptoms, which contaminates the behavioural readout of motor learning by limiting overall motor performance and, consequently, the range of training-induced performance gains. It is impossible to distinguish the effects of DBS on motor learning from temporary DBS-associated effects on motor performance in this context. However, this distinction is essential as conditions that affect execution do not necessarily have to affect learning.37 The alternative interpretation for the assumption that DBS improves early motor learning is that impaired motor execution due to DBS withdrawal prevented any training-induced performance improvements that could have indicated online learning. Different levels of contamination of performance gains with impairments of motor execution (e.g. due to differences in dopaminergic medication or disease stage) may also at least partly explain the inconsistent results of previous research in terms of whether motor sequence learning is impaired in PD or not.46 Our current results suggest that not only general motor execution but also learning dynamics during initial training were still significantly impaired in PD compared with age-matched healthy controls despite ‘best possible’ treatment with subthalamic DBS and dopaminergic medication. However, PD patients on active DBS continued to show clinically relevant impairments of motor execution due to remaining Parkinsonian motor symptoms. Therefore, we cannot rule out the possibility that the apparent differences between PD patients and HCs in terms of early learning dynamics in the current study are still actually driven by differences in motor execution.Motor learning is traditionally defined as an improvement in motor performance through practice. According to this definition and if only the initial training session of our study is considered, our results are in line with previous evidence, suggesting that subthalamic DBS improves early motor learning compared with impaired learning under inactive DBS.37 A link between the neural substrates underlying, on the one hand, online encoding of motor sequence memory traces during training and, on the other hand, offline consolidation, is provided by several functional imaging studies which demonstrated that training-induced changes of motor task-related activity and connectivity predict subsequent consolidation.34-36 This could mean that activation in an online motor learning-related network during training is necessary to induce consolidation. However, in the current study, motor sequence performance after the 6 h offline consolidation interval did not relevantly differ regardless of whether initial training was performed under ‘optimal’ (active DBS) or impaired (inactive DBS) motor execution conditions. This may indicate that encoding of motor sequence memory traces during initial training was similarly effective under active and inactive DBS despite severely impaired task execution under the latter condition. One could still argue that the significant difference with respect to sequence performance during the EarlyRT may well indicate improved early learning under active DBS since worsened motor symptoms under inactive DBS had already recovered to the level of the DBS-ON experiment at this time. However, PD patients reported significantly higher hand fatigue after training under inactive DBS despite ‘normalization’ of task-relevant Parkinsonian motor symptoms. As neuromuscular fatigue itself may degrade task execution,48 this might at least partly explain the performance differences across early retesting without having to assume relevant differences in prior learning. However, even if task performance differences during early retesting were indeed indicative of improved learning under active DBS, this advantage is lost across the offline consolidation interval. A similar pattern was observed in age-matched HCs indicating that the ability of PD patients to consolidate training-induced performance gains is not inferior to that of age-matched HCs. This corroborates previous evidence showing similar overnight and over-the-day motor memory consolidation in PD and age-matched HCs.25 The observation that consolidation was even relatively enhanced in PD patients following prior training under inactive DBS further supports that the capacity to consolidate motor memories is relatively intact in PD. Importantly, we do not suggest that suspending DBS during training enhances later motor memory consolidation. Rather, intact offline motor memory consolidation in PD was the precondition to compensate for the inhibition of performance gains during initial training when the ability to improve performance—but not the ability to learn—was taken by the withdrawal of DBS.Importantly, the ultimate goal of motor training is not to temporarily promote motor performance during the period of practising, but to induce sustained improvements in motor skills. Moreover, given that performance-learning distinction is especially evident under challenging training conditions (which is the case in a PD patient who has been withdrawn from DBS), delayed recall of training-induced learning after consolidation may represent a more valid, however indirect, indicator of how much was actually learned during training.49 direct alteration of M1 excitability by DBS50 and reduction of M1 activity by DBS over time.51 The significant connectivity to frontal perisylvic areas (e.g. SMA) and basal ganglia is plausible and clinically relevant.52-54 However, no significant voxels of VTA-to-whole-brain connectivity were associated with DBS-dependent differences in performance gains during training (‘early learning’) or Parkinsonian motor symptom improvements. Following the approach by de Almeida Marcelino et al.,28 we calculated R-maps for DBS-associated differences in performance gains during training and, in addition, DBS-induced motor symptom improvements. The resulting R-map pattern for DBS-induced motor symptom improvements with positive correlations to frontal and parietotemporal regions and negative correlations to central regions is in line with previous results.55 The R-map pattern for DBS-induced differences in performance gains during training was different from the pattern associated with DBS-induced improvements of motor symptoms and visually similar to the connectivity pattern that was associated with DBS-induced effects on ‘early learning’ in de Almeida Marcelino et al.28 Different connectivity patterns of DBS-associated differences in early learning and Parkinsonian motor symptom improvements may seem to support a specific role of subthalamic DBS in motor learning apart from facilitating motor execution in PD. However, since R-maps are created based on the behavioural metrics, the contamination of behavioural metrics by the learning-performance distinction problem also confounds the generation of the R-maps. Because the DBS-induced differences in performance gains during training and DBS-induced motor symptom improvements were not correlated at the behavioural level, it is not surprising that a lack of association was found between these parameters when expressed in terms of connectivity in the joint fMRI data set. Different R-map patterns of connectivity related to DBS-associated differences in ‘learning’ and improvements of Parkinsonian motor symptoms, thus, do not indicate specific subthalamic DBS involvement in inherent motor learning processes.We then explored whether specific DBS-connectivity patterns could be identified that underlie DBS-associated effects on early motor learning. In line with previous research, the resting-state fMRI analysis demonstrated plausible significant connectivity between the VTAs and several cortical areas in a cohort of healthy participants. Significant connectivity between subthalamic nucleus (STN) and the primary motor cortex is in line with studies demonstrating the hyperdirect pathway,56-58 However, their function in motor control and motor learning likely differs. Specifically, it has been shown that within the striatum, early motor learning is supported by the activation of associative subareas, whereas activation of sensorimotor subareas of the striatum is involved in the execution of already well-learned sequences.59-61 The sensorimotor STN, however, rather affects motor execution by modulating the excitatory control over the inhibitory basal ganglia motor output to the thalamus and the cortex.62 Facilitation of movement execution as mediated by the STN is associated with suppression of beta oscillations in the STN that is tightly linked to movement preparation and movement execution.63-68 In PD, pathologically exaggerated beta oscillations were linked to motor symptoms such as bradykinesia and rigidity.69-71 Although the exact mechanisms of how DBS improves Parkinsonian motor symptoms remain elusive, suppression of pathologically increased beta oscillations by high-frequency interruption of the sensorimotor STN is likely one key mechanism.73 However, given the above evidence that motor execution and motor learning rely on finely tuned temporal dynamics of beta oscillations in the STN and the associated cortico-basal ganglia circuits, it seems unlikely that constant unspecific disruption of STN activity by DBS may facilitate such complex and timing-critical processes in a specific manner. These considerations are in line with our current findings that indicate a fundamental role of the STN in global motor control that is well accessible to modulation by DBS, while modulation of STN activity by DBS had no relevant effect on motor learning itself when DBS-induced effects on motor execution were accounted for. However, DBS-associated changes in performance gains across initial training did not significantly correlate with DBS-induced modulation of Parkinsonian motor symptoms despite a generally strong negative association of performance gains during training and Parkinsonian motor symptom load. Like in previous studies, this may be interpreted as evidence that DBS modulates motor learning independent of effects on motor execution. However, the decorrelation of these metrics is, again, likely driven by the inhibition of training-induced performance gains in the DBS-OFF experiment due to severe impairments in motor execution . Of note, when DBS was on , training-induced performance gains were significantly correlated with PD motor symptom expression. This indirectly supports that DBS rather provides the precondition to improve performance by facilitating motor execution than to directly modulate motor learning.Our findings corroborate current concepts regarding the role of the STN in motor control. Both the striatum and the STN are input structures to the basal ganglia and are subdivided into sensorimotor, associative and limbic subareas based on cortical connectivity.Although subthalamic DBS led to a well-established improvement in Parkinsonian motor symptoms and motor execution, the current study showed that subthalamic DBS had no specific effects on motor learning. This is evidenced by the fact that task performance at delayed retesting was similar across experiments despite large DBS-dependent differences in motor execution during initial learning. Moreover, despite plausible patterns of VTA-to-whole-brain connectivity, we found no particular connectivity patterns that suggested a role of the stimulated portion of the STN in motor learning when contrasted to the role of the STN in Parkinsonian motor symptom modulation. This supports that the STN has an important role in general motor control, while it does not modulate motor learning, at least not directly. Importantly, offline consolidation was intact in PD patients as inhibition of motor performance gains during initial training under inactive DBS was later compensated across offline consolidation. From a clinical perspective, this suggests that it is not necessary for PD patients to wait for an optimal motor state to practice a new motor skill, as longer-term outcomes, including an offline consolidation phase, appear to be independent of the magnitude of performance gains during initial training.fcad070_Supplementary_DataClick here for additional data file.


Neutrosophic multicriteria is a method of decision-making that uses indeterminacy to combine several criteria or elements, frequently with incomplete or ambiguous information, to find a solution. The neutrosophic multicriteria analysis enables the assessment of qualitative and subjective aspects and can assist in resolving conflicting goals and preferences. In the Neutrosophic Multi-Attribute Group Decision Making (NMAGDM) problems, all the information provided by the decision makers (DMs) is expressed as single value neutrosophic triangular and trapezoidal numbers examined in this study which can provide more flexibility and accuracy in capturing uncertainty and aggregating preferences. We offer a novel approach for determining the neutrosophic possibility degree of two and three trapezoidal and triangular neutrosophic sets and the concepts of neutrosophic possibility mean value. The trapezoidal and triangular neutrosophic Bonferroni mean (TITRNBM) operator and the trapezoidal and triangular neutrosophic weighted Bonferroni mean (TITRNWBM) operator are two aggregation methods we then create. Further, we examine the TITRNBM and TITRNWBM attributes and their uniqueness. The NMAGDM approach with trapezoidal and triangular information is suggested based on the TITRNWBM operator and possibility degree. Finally, a concrete example of manufacturing companies searching for the best supplier for assembling the critical parts is provided to validate the established strategies and show their practical applicability and efficacy. Chen2 explained the evaluation of aggregative risk rate utilizing the development of software of fuzzy sets in the fuzzy group decision-making environment. Wang and Lin3 developed a method of selecting the configuration items using the software. The compromise programming method solves the above problem (FMAGDM) by taking the aggregating function as Li4 introduces fuzzy weighted Minkowski distance. A maximizing deviation method is used to solve the above problem (FMAGDM) in the linguistic atmosphere by Wu and Chen5. The practical, interactive procedure used for solving the above method (FMAGDM), where the attribute weights are given partially, is explained by Xu6. Lin and Wu7 use a simple analytical method. Also, a computing coordination method was proposed to solve the above method (FMAGDM) was explained by Tsai and Wang8. A multi-granularity linguistic method is used to solve the above problem (FMAGDM) is explained in Fan and Liu9. Using the non-homogenous information, different distance values have been measured, and a different method is developed to solve the above (FMAGDM) presented in Li10. However, all the above method is based on type-1 fuzzy sets.The problem of group decision-making in multi-attributes using Fuzzy (FMAGDM) is the method used to find the feasible alternative when the group decision makers' information is uncertain because of the complication in the social environment, economic environment, and unclear subject thinking of human nature. In past years several methods were used to solve the above problem (FMAGDM) with the help of type-1 fuzzy sets. Chen11 first initiated the extension of type-1 fuzzy sets to type-2 fuzzy sets. The type-2 fuzzy set solved more uncertainty compared to the type-1 fuzzy set by crisp the numbers of the type-1 fuzzy set as used as the membership value for type-2 fuzzy sets introduced in Wu and Mendel12. Because of the complexity of using type-2 fuzzy sets, the interval type-2 fuzzy sets were presented by Mendal et al.13 and applied in many practical applications, as given in Mendal and Wu17. A new Linguistic weighted average method is imposed in interval type-2 fuzzy sets to solve the above problem (FMAGDM) given in Wu and Mendal19. The FMAGDM is solved using the ranking method and arithmetic operations in interval type-2 fuzzy sets, as provided by Chen and Lee20. Also, the TOPSIS method is applied to solve. FMAGDM uses interval type-2 fuzzy sets, which is explained in Chen and Lee21. Even though the attribute weights are partially known, the interval type-2 fuzzy set used in characterizing the attribute values is clearly explained in Wang and Liu22. A ranking method in interval type-2 fuzzy set to solve the FMAGDM method is introduced by Chen and Yang23. A new method was introduced to solve FMAGDM using a trapezoidal interval type-2 fuzzy set by Zhang and Zhang24. A technique of possibility degree used to solve the FMAGDM problem is explained in Hu et al.25.Zadeh26 mean operator is used in interval type-2 fuzzy set to solve the FMAGDM problem, as explained in Gong et al.27. Using the weighted geometric Bonferroni operator and the possible degree of interval type-2 fuzzy set, an FMAGDM problem is solved. Peng and Smarandache28 examined the single-valued neutrosophic Dombi Bonferroni mean operator, single-valued neutrosophic weighted Dombi Bonferroni mean operator, single-valued neutrosophic Dombi geometric Bonferroni mean operator and single-valued neutrosophic weighted Dombi geometric Bonferroni mean operator mobile to illustrate the cloud computing industry decision making problem. Awang et al.29 proposed an interval-valued neutrosophic Shapley normalized weighted Bonferroni mean (INSNWBM) operator and explored the applicability of the INSNWBM in decision-making. Banerjee et al.30 introduced the generalized partitioned Bonferroni mean (GPBM) in an interval-valued fuzzy set based on the strict t-conorms additive generators. They developed the interval valued GPBM (IVGPBM) and the weighted IVGPBM (WIVGPBM) aggregation operators to study multi-attribute decision-making problems. Deli31 developed the generalized trapezoidal hesitant fuzzy Bonferroni arithmetic mean operator and generalized trapezoidal hesitant fuzzy Bonferroni geometric mean operator for aggregating the generalized trapezoidal hesitant fuzzy information in order to discuss the multi-attributes decision-making problems. Further, the multi-attribute group decision-making problems analysed by Bonferroni mean operators in the picture hesitant fuzzy numbers environments32. Ali et al.33 derived complex q-rung orthopair fuzzy Archimedean Bonferroni mean and weighted Bonferroni mean operators and examined the interrelationship among the finite number of attributes in modern data fusion theory. Chakraborty and Saha34 studied the Fermatean fuzzy multi-criteria group decision making with the help of Bonferroni mean and weighted Bonferroni mean operators for the healthcare industry. In order to improve the possibility degree and a better solution in this paper, we use the single value neutrosophic method. The accuracy has been increased when using the neutrosophic rather than the interval type-2 fuzzy sets and other generalizations. Hence, we present a new method to solve the FMAGDM problem by using two aggregate methods, such as the trapezoidal and triangular neutrosophic Bonferroni mean (TITRNBM) operator and the trapezoidal and triangular neutrosophic weighted Bonferroni mean (TITRNWBM) operator. FMAGDM problem is to find the most desirable alternative from a set of feasible alternatives, where the information provided by a group of decision makers is usually uncertain or fuzzy due to the increasing complexity of the socio-economic environment and the vagueness of inherent subjective nature of human thinking. Hence, the significant advantage of the proposed operator is that they have considered the interrelationships of aggregated values. Hence, we have employed an illustration related to a manufacturing company searching for the best supplier for assembling the critical parts to validate the proposed operators' practical applicability and effectiveness.The Bonferroni operator is a mathematical operator used in decision-making and statistical analysis. Its advantages make it a valuable tool in specific contexts, such as conservatism, simplicity, broad applicability, flexibility and control of Type I errors. FMAGDM models can capture and handle the uncertainty and ambiguity inherent in decision-making processes by employing the neutrosophic Bonferroni operator. The Neutrosophic Bonferroni operator considers each attribute's membership, indeterminacy, and non-membership degrees, providing a comprehensive and balanced aggregation of the decision-maker's opinions. The scope of the neutrosophic Bonferroni operator in FMAGDM lies in its ability to handle uncertain and indeterminate information. It enables decision-makers to express their preferences more nuancedly, leading to more accurate and reliable decision outcomes. However, it is essential to note that the neutrosophic Bonferroni operator is just one of many methods available for FMAGDM, and its suitability depends on the specific context and requirements of the decision problem at hand. A BonferroniThus, the paper is formulated in “In this section, we define some definitions and arithmetic operations for a neutrosophic set used in forthcoming sections.Smarandache35) Let (Wang36) Let ,,4), neutStep 4:Then use  to deterStep 5:Then find the neutrosophic preference matrix FP using  which isStep 6:By using Eq.  the neutStep 7:Finally using , the ranStep 8:The ranking will be given in the descending order Step 9:Now we will give a comparative study with the previous methods in Table The conventional Bonferroni mean operator and possibility degree have been extended to the trapezoidal and triangular neutrosophic environment to better organize and model the uncertainties and indeterminacy inside multi-attribute decision analysis. In FMAGDM, the neutrosophic Bonferroni operator can aggregate individual preferences or evaluations of multiple decision-makers. Neutrosophic environments, as opposed to trapezoidal and triangular ones, can convey the decision-makers' uncertainty, indeterminacy, and ambiguity. We have introduced a novel approach for NMAGDM based on the neutrosophic possibility degree and the TITRNWBM operator. We also offer numerical examples to show how the proposed method's NMAGDM process works for a manufacturing company searching for the best supplier for assembling the critical parts. The outcome demonstrates that the suggested approach gives us a practical means of resolving NMAGDM issues based on trapezoidal and triangular neutrosophic environments. Future work will apply the proposed techniques to other decision-making issues involving Plithogenic environments.


Case Presentation. A 77-year-old male with terminal diabetic nephropathy complained of dialysis-induced hypotension due to AF and was admitted to our hospital for catheter ablation. Here, we report a case of non-iatrogenic localized-reentrant figure of eight AT in the SVC.  The superior vena cava (SVC) is an important non-pulmonary venous foci of atrial fibrillation (AF) and is known as the arrhythmogenic site of scar-related atrial tachycardia (AT). Scar-related ATs may occur after catheter ablation and open heart surgery; however, idiopathic AT rarely occurs.  SVC has the arrhythmogenic potential for re-entrant tachycardia, and the development of mapping technology can reveal arrhythmogenic mechanisms. It is well known that scar-related atrial tachycardias (ATs) may occur after catheter ablation and open heart surgery . The eleCurrently, activation mapping technology is being developed. Three-dimensional mapping using a coherent map integrated with a vector and velocity map  helps to identify the mechanism of arrhythmia, allowing us to differentiate a focal source from a localized reentry . Here, wA 77-year-old man with terminal diabetic nephropathy complained of dialysis-induced hypotension due to atrial fibrillation (AF) and was admitted to our hospital for catheter ablation. He was receiving dialysis via the left hand's autologous arteriovenous fistula. We performed circumferential pulmonary vein isolation using a Thermo-Cool STSF catheter (Biosense Webster Inc.) under CARTO®3 version 7, and achieved bidirectional blocks of both pulmonary veins. After the procedure, 200 ms burst programmed stimulation of the atrium induced AT with a cycle length of 190 ms. The activation sequence of the AT demonstrated constantly from proximal to distal in the coronary sinus (CS) and from superior to inferior in the right atrium (RA), and early activations were located at the SVC site. The SVC and RA maps were acquired using a multielectrode mapping catheter  and the coherent map module. Electrical activation revealed localized reentry on the SVC, appearing as a double loop circuit or a figure of eight (Supplemental Videos 1 and Figures The main findings of this case were the arrhythmogenic possibility of SVC and the efficacy of coherent mapping.First, we described a patient with non-iatrogenic localized-reentrant AT on the SVC. SVCs are known to be the foci site of AF and the arrhythmogenic site of scar-related AT , and cleSecond, we recognize AT as a localized reentry because a coherent map revealed the circuit of the AT and slow conduction isthmus. However, conventional activation mapping based on local activation time alone could not describe the slow conduction regions due to inaccurate annotation of fragmented electrograms, and the tachycardia appeared to be a focal AT (Supplemental Video 2, The coherent map was useful for differentiating a localized reentrant mechanism from a true focal mechanism; thus, we may easily recognize the localized reentrant tachycardias that appear as focal tachycardias mapped by the conventional activation mapping system. A more developed mapping technology permits more frequent detection of localized-reentrant ATs in the future; thus, SVC-localized reentrant ATs may become less rare. Furthermore, continuous mapping technology development will continue to improve the recognition of arrhythmogenic mechanisms and contribute to enhanced procedural outcomes of AT ablation.


Schizophrenia (SZ) is a complex disorder with a highly polygenic inheritance. It can be conceived as the extreme expression of a continuum of traits that are present in the general population often broadly referred to as schizotypy. However, it is still poorly understood how these traits overlap genetically with the disorder. We investigated whether polygenic risk for SZ is associated with these disorder-related phenotypes  in a sample of 253 non-clinically identified participants. Polygenic risk scores (PRSs) were constructed based on the latest SZ genome-wide association study using the PRS-CS method. Their association with self-report and interview measures of SZ-related traits was tested. No association with either schizotypy or psychotic-like experiences was found. However, we identified a significant association with the Motor Change subscale of the Comprehensive Assessment of At-Risk Mental States (CAARMS) interview. Our results indicate that the genetic overlap of SZ with schizotypy and psychotic-like experiences is less robust than previously hypothesized. The relationship between high PRS for SZ and motor abnormalities could reflect neurodevelopmental processes associated with psychosis proneness and SZ.The online version contains supplementary material available at 10.1007/s00406-023-01633-7. Schizophrenia (SZ) is a severe and disabling mental disorder that affects around 24 million people worldwide . Family According to the dimensional view of mental disorders, the psychosis phenotype is manifested across a dynamic continuum in which SZ represents the most extreme of a much broadly distributed clinical expression of psychosis liability expressed as schizotypy traits and psychotic-like experiences in the general population –9. SZ anTo date, little is known about the contribution of genetic risk loci for SZ to SZ-related traits in the general population . In the In the field of psychosis proneness, studies applying PRSs for SZ (SZ-PRSs) to examine the genetic overlap between SZ and its related subclinical phenotypes so far have led to controversial results. On the one hand, several previous studies failed to detect an association between SZ-PRSs and psychotic-like experiences when examining population-based samples of varying sample sizes e.g., –28). Sim. Sim28])Given this background, the aim of this study was to examine the contribution of SZ genetic risk variants to SZ-related traits by analyzing whether SZ-PRSs are associated with SZ-related phenotypes in a sample of non-clinical young adults. The phenotyping of participants was enriched by including the assessment of self-reported traits and psychotic-like experiences as well as face-to-face interviews of a broad range of subclinical experiences and symptoms.Universitat Autònoma de Barcelona (UAB) and 261 students from seven technical training schools in Barcelona were initially screened with self-report questionnaires. At T2, a subsample of 253 individuals  oversampled for schizotypy scores to ensure enough variance in the construct of interest was selected to conduct in depth examinations comprising a wide range of interview, questionnaire and experience sampling methodology measurements. This study uses data from the 253 subjects of this T2 subsample, although 25 of them were excluded during the quality control of genetic data. Out of the final 228 participants, 164 were women (71.9%) and 64 were men (28.1%); with a mean age of 19.6 years  and 20.8 , respectively. Seven percent of them had a family history of psychotic disorder. All subjects volunteered to take part in the study and provided written informed consent when the assessments were carried. Ethical approval was obtained from local research ethics committees.The sample of the present study was part of the ongoing Barcelona Longitudinal Investigation of Schizotypy Study (BLISS) –40. At Tnever), 2 (sometimes), 3 (often), to 4 . The positive and negative dimensions were used in this study.Psychotic-like experiences were assessed with the Spanish version of the Community Assessment of Psychic Experiences (CAPE) , which hSchizotypy was assessed with the Wisconsin Schizotypy Scales (WSS), which include the Perceptual Aberration, Magical Ideation, Revised Social Anhedonia and Physical Anhedonia scales –47. SubjAll participants were interviewed by trained psychologists with the Comprehensive Assessment of At-Risk Mental States (CAARMS) . This seCentro Nacional de Genotipado  using the Illumina Infinium Global Screening Array-24 v2.0 (GSA) BeadChip. GenomeStudio v2.0.4  was used to generate the genotype calls. The quality control (QC) was carried out with PLINK v1.9 (www.cog-genomics.org/plink/1.9/) )Other plausible explanations for such a lack of associations in the literature have been pointed out. Nenadić et al.  suggesteAnother plausible explanation for the increasing number of negative results in previous research could be that, like SZ, its related subclinical phenotypes might also be determined by different types of genetic variants beyond common SNPs considered in PRS computation. In fact, SNP-based heritability estimates for SZ indicate that common variation only explains around 24% of the variance in SZ liability . Thus, fRegarding the CAARMS interview, our findings seem to identify an association between the polygenic risk for SZ and the presence of motor abnormalities. We found an association with the Motor/physical Change subscale, which evaluates subjectively experienced difficulties with movement and objective signs of catatonia, including: subjective complaints of impaired motor functioning; informant reported or observed changes in motor functioning; subjective complaints of impaired bodily sensation; and subjective complaints of impaired autonomic functioning . IndividSome studies have estimated that up to 80% of patients with SZ present some motor anomalies, already observed very early during premorbid development in most of these patients . These aThe findings of the present study should be interpreted with caution bearing in mind some limitations. On the one hand, given the face-to-face nature of part of the psychometric assessment, our sample was relatively small for the type of investigation carried out and a slight lack of statistical power has to be acknowledged. On the other hand, the sex-stratified analyses performed may be biased since more than 70% of the participants were women and the size of the male subsample (N = 64) will likely have affected our statistical power. Additionally, we had no knowledge of the developmental and drug use history of the participants, which could have added an interesting insight to the analyses carried out. Finally, due to the non-clinical nature of the sample analyzed in this study, most participants reported relatively low scores on the psychometric scales. On the CAARMS interview, especially, a clear floor effect could be observed as this interview was initially designed to evaluate help-seeking individuals rather than non-clinical subjects—although we highlight that the present sample was oversampled for both positive and negative schizotypy and psychotic-like experiences from a larger unselected sample. Thus, the CAARMS variables were dichotomized, which might have led to a loss of statistical power . Even soIn conclusion, our results seem to suggest that schizotypy and psychotic-like experiences share less genetic variability with SZ than initially hypothesized and that SZ-PRSs are able to capture the subjective motor changes measured with the CAARMS interview presented in some healthy subjects from the general population. Further studies in larger non-clinical samples are required in order to finally unravel the shared genetic background between this disorder and its subclinical phenotypes and to ensure the replicability of the association with motor abnormalities found in the present study. Moreover, the replication of this finding across levels of severity expression  would allow us to both understand more in depth the nature of this association and test whether, as it would be expected, this association becomes more evident at greater severity expressions of the extended psychosis phenotype that presumably index increasing genetic load for SZ.Supplementary file1 (DOCX 34 KB)Below is the link to the electronic supplementary material.