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Swoboda, S.

Publications and source records attributed to Swoboda, S..

3 recordsLinked to original sources

Experimentally induced pain and paresthesia respond differently to cuff-based compression

Neuropathic pain is a significant therapeutic challenge due to the co-occurrence with other neurological symptoms such as paresthesia. Human-based models such as cuff algometry can enhance our understanding of pain-paresthesia relationships. This experiment aimed to characterize (psychophysically) pain and paresthesia evoked by stimuli of different temporal and intensity parameters and to demonstrate the reliability of experimental induction of these two symptoms using cuff algometry. Forty participants, aged 18-35, were exposed to mechanical pressure stimuli at three intensities (100, 150, 200 mmHg) and three durations (90, 120, 150s). Skin Conductance (SC) was continuously monitored, and participants rated pain and paresthesia in real-time using a computerized visual analog scale. The General Linear Model analysis revealed significant differences in paresthesia across all durations (p<0.01), but not all intensities, as paresthesia did not increase from 150 to 200 mmHg (p>0.05). Conversely, pain responses showed significant differences across all pressure intensities (p<0.05) but not durations, as pain did not increase from 90 to 120 and from 120 to 150s (p>0.05). No interaction effects were found for either symptom. SC analysis showed no significant main or interaction effects. Intraclass correlation coefficients (ICCs) indicated moderate to good reliability for pain and paresthesia induction across different durations and intensities (ICC: 0.52-0.90), while SC showed poor to moderate reliability (ICC: 0.21-0.73). In conclusion, computerized cuff algometry seems to be an effective and reliable method for simultaneously inducing and assessing pain and paresthesia, revealing that these symptoms follow different patterns based on pressure duration and intensity.

physiology↗

Single-cell analysis of myeloid cells in HPV+ tonsillar cancer

The incidence of Human Papillomavirus positive (HPV+) tonsillar cancer has been sharply rising during the last two decades. Myeloid cells represent an appropriate therapeutic target due to their ability to orchestrate antigen-specific immunity within the tonsil, the availability of viral antigens, and the proximity of the tumor and the underlying lymphoid tissue. However, the interrelationship of steady-state and inflammatory myeloid cell subsets, and their impact on patient survival remains unexplored. Here, we used single-cell RNA-sequencing to map the myeloid compartment in HPV+ tonsillar cancer. Our analysis unveiled the existence of four dendritic cell lineages, two macrophage polarization processes, and their sequential maturation profiles. We observed an expansion of the myeloid compartment in HPV+ tonsillar cancer, accompanied by interferon-induced cellular responses both in DCs and monocyte-macrophages. Within the DC lineages, we describe a balance shift in the frequency of progenitor and mature cDC favoring the cDC1 lineage in detriment of cDC2s, in HPV+ lesions. Furthermore, we observed that all DC lineages apart from DC5s matured into a common activated DC profile. In turn, the monocyte-macrophage lineage was subjected to early monocyte polarization events, which gave raise to inflammatory-activated, and chemokine-producing macrophages. We validated the existence of most of the single-cell RNA-seq clusters using 26-plex flow cytometry, and described a positive impact of cDC1, activated DCs and macrophages in patient survival using signature scoring. The current study contributes towards the understanding of myeloid ontogeny and dynamics in human papilloma driven tonsillar cancer, and details myeloid biomarkers that can be used to predict therapy effects and assess patient prognosis.

immunology↗

Reproducibility of spatial summation of pain effect during COVID-19 pandemic

The purpose of this study was to reproduce the previously observed spatial summation of pain effect (SSp) using non-laboratory procedures and commercial equipment. An additional aim was to explore the association between expectations and SSp. The Cold Pressor Task (CPT) was used to induce SSp. Healthy participants (N=68) immersed their non-dominant hands (divided into 5 segments) into cold water (CPT). Two conditions were used 1) gradual hand immersion (ascending condition) and 2) gradual hand withdrawal (descending condition). Pain intensity was measured on a Visual Analogue Scale (VAS). Psychological factors, such as the participants expectations of pain intensity were also measured on a VAS. Results showed significant SSp (X2(4) = 116.90, p < 0.001), reproduced with non-laboratory equipment in a home-based set-up. Furthermore, two novel findings were observed: i) there was a significant correlation between expectations and perceived pain, indicating a link between pain expectations and SSp, ii) spatial summation increased with the increase in duration exposure to the noxious stimulus (Wald X2(8) = 80.80, p < 0.001). This study suggests that SSp is associated with pain expectations and can be formed by a mixture of excitatory and inhibitory mechanisms potentially driven by temporal characteristics of neural excitation. Moreover, this study proposes a new feasible way to induce SSp using a home-based set-up.

physiology↗