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BMC Sports Science, Medicine &... Oct 2023Practical blood flow restriction (pBFR) during exercise is a cost-saving alternative to traditional blood flow restriction using pneumatic cuffs, particularly when...
Influence of cuff stiffness on hemodynamics and perceived cuff pressure in the upper extremities in males and females: implications for practical blood flow restriction training.
BACKGROUND
Practical blood flow restriction (pBFR) during exercise is a cost-saving alternative to traditional blood flow restriction using pneumatic cuffs, particularly when exercising in a group setting. Depending on the pBFR technique, several factors (e.g., cuff width, limb circumference) have already been shown to be of importance when applying the pBFR pressure. Given that elastic cuffs are often used for pBFR, the cuff stiffness might be an additional influencing factor. Therefore, the present study compared the acute effects of three elastic cuffs with identical width but different stiffness (high stiffness (HS), medium stiffness (MS), and low stiffness (LS)) on hemodynamic measures and perceived cuff pressure at rest.
METHODS
In a randomized, counter-balanced cross-over study, 36 young and normotensive participants completed three experimental trials. After a 10-min rest period in supine position, the cuff was loosely and proximally applied to the right upper arm. Following baseline data recording, the cuff was successively tightened in 10%-increments with respect to the limb circumference (%overlap) until arterial blood flow was occluded. At baseline and during each %overlap, systolic peak blood flow velocity of the brachial artery, rating of perceived cuff pressure, as well as muscle oxygen saturation and total hemoglobin concentration of the biceps brachii muscle were recorded.
RESULTS
The %overlap required to occlude arterial blood flow was different between the three cuffs (HS: 30.9 ± 3.8%, MS: 43.9 ± 6.1%, LS: 54.5 ± 8.3%). Furthermore, at 30% overlap, systolic peak blood flow velocity was lower when applying the HS (9.0 ± 10.9 cm∙s) compared to MS (48.9 ± 21.9 cm∙s) and LS cuff (62.9 ± 19.1 cm∙s). Rating of perceived cuff pressure at 30% overlap was higher when using the HS (6.5 ± 1.5 arbitrary unit (a.u.)) compared to MS (5.1 ± 1.4 a.u.) and LS cuff (4.9 ± 1.5 a.u.) with no difference between the MS and LS cuff. However, muscle oxygen saturation and total hemoglobin concentration were not different between the three cuffs.
CONCLUSIONS
The present study revealed that the cuff stiffness influenced blood flow velocity and arterial occlusion pressure. Therefore, cuff stiffness seems an important factor for the application of pBFR.
PubMed: 37858237
DOI: 10.1186/s13102-023-00745-w -
Frontiers in Pediatrics 2024In contrast to significant declines in deaths due to lung cancer and cardiac disease in Westernised countries, the mortality due to 'chronic obstructive pulmonary... (Review)
Review
In contrast to significant declines in deaths due to lung cancer and cardiac disease in Westernised countries, the mortality due to 'chronic obstructive pulmonary disease' (COPD) has minimally changed in recent decades while 'the incidence of bronchiectasis' is on the rise. The current focus on producing guidelines for these two airway 'diseases' has hindered progress in both treatment and prevention. The elephant in the room is that neither COPD nor bronchiectasis is a disease but rather a consequence of progressive untreated airway inflammation. To make this case, it is important to review the evolution of our understanding of airway disease and how a pathological appearance (bronchiectasis) and an arbitrary physiological marker of impaired airways (COPD) came to be labelled as 'diseases'. Valuable insights into the natural history of airway disease can be obtained from the pre-antibiotic era. The dramatic impacts of antibiotics on the prevalence of significant airway disease, especially in childhood and early adult life, have largely been forgotten and will be revisited as will the misinterpretation of trials undertaken in those with chronic (bacterial) bronchitis. In the past decades, paediatricians have observed a progressive increase in what is termed 'persistent bacterial bronchitis' (PBB). This condition shares all the same characteristics as 'chronic bronchitis', which is prevalent in young children during the pre-antibiotic era. Additionally, the radiological appearance of bronchiectasis is once again becoming more common in children and, more recently, in adults. Adult physicians remain sceptical about the existence of PBB; however, in one study aimed at assessing the efficacy of antibiotics in adults with persistent symptoms, researchers discovered that the majority of patients exhibiting symptoms of PBB were already on long-term macrolides. In recent decades, there has been a growing recognition of the importance of the respiratory microbiome and an understanding of the ability of bacteria to persist in potentially hostile environments through strategies such as biofilms, intracellular communities, and persister bacteria. This is a challenging field that will likely require new approaches to diagnosis and treatment; however, it needs to be embraced if real progress is to be made.
PubMed: 38910961
DOI: 10.3389/fped.2024.1391290 -
Respiratory Medicine Feb 2024The quality of e-Consultations in the COPD is unknown. The objectives of this study were (i) to evaluate the quality of referrals; (ii) to define the characteristics of... (Observational Study)
Observational Study
INTRODUCTION
The quality of e-Consultations in the COPD is unknown. The objectives of this study were (i) to evaluate the quality of referrals; (ii) to define the characteristics of patients referred from Primary Care (PC) to the Unit of Pulmonology; and (iii) to describe differences between accepted and rejected patients.
METHODS
A retrospective, observational study of e-Consultations requested by PC for suspected COPD throughout 2022. To quantify the quality of the e-Consultations, an arbitrary scale of 12 variables (score 0-10) was created.
RESULTS
In total, 384 e-Consultations were reviewed, of which 167 (43.5 %) resulted in a face-to-face visit, and 217 (56.5 %) were rejected. No differences were observed between the two types of patients, except for confirmations of diagnostic suspicion of COPD [significantly higher in accepted patients (p = 0.042)]; physical examination data of rejected patients (more data provided; p = 0.015); and lung function (significantly better in rejected patients). The mean quality of referrals was acceptable (5.6 ± 2.1 score): 121 (31.3 %) had insufficient quality; 118 (30.5 %) acceptable; 75 (19.4 %) good, and 30 (7.8 %) excellent. Quality was low in half of the variables analyzed (6/12); acceptable in 3, and good in another 3. The capacity of resolution of referrals was good (one e-Consultation) in 199 requests (66.1 %); deficient (two e-Consultations) in 72 (23.9 %), and poor (≥3 e-Consultations) in 30 (10 %). Overdiagnosis was 40.2 % (86/214 e-Consultations). The risk could be classified in 247 patients (64.3 %; 135 low-risk; 90 high-risk).
CONCLUSIONS
When adequate information is provided, e-Consultations help identify different levels of severity. However, the quality and capacity of resolution of referrals were suboptimal, with a high percentage of overdiagnoses.
Topics: Humans; Retrospective Studies; Pulmonary Disease, Chronic Obstructive; Referral and Consultation
PubMed: 38171405
DOI: 10.1016/j.rmed.2023.107514 -
Clinical Rheumatology Oct 2023The study aims to increase the understanding regarding the role of regulatory T cells (Tregs) in lupus nephritis (LN) and ANCA-associated vasculitis (AAV) by comparing...
The study aims to increase the understanding regarding the role of regulatory T cells (Tregs) in lupus nephritis (LN) and ANCA-associated vasculitis (AAV) by comparing their localization in renal tissue and changes following immunosuppressive therapy. Kidney biopsies from 12 patients with LN and 7 patients with AAV were examined. Kidney biopsies had been performed both at active disease and following immunosuppressive treatment. Clinical data was collected at both biopsy occasions. Expression of Forkhead Box P 3 (Foxp3) in renal tissue was assessed by immunohistochemistry. An arbitrary scale was used to estimate the number of Foxp3+ cells. In LN, 8/12 (67%) had positive tissue staining for Foxp3 at baseline, most pronounced in inflammatory infiltrates, but also interstitially and in a peri-glomerular pattern. At second biopsies, after immunosuppressive treatment, 4/12 (33%) still had detectable Foxp3+ cells, found in persisting inflammatory infiltrates and some in the interstitium. Patients with a good clinical response to treatment had high grade of Foxp3+ cells in first biopsies. In AAV, only 2/7 (29%) had positive staining for Foxp3 at baseline, in inflammatory infiltrates and to a lesser extent in the interstitium, despite large areas of inflammatory infiltrates in all patients. At follow-up, 2/7 (29%) biopsies were positive for Foxp3. Our data show a higher presence of Foxp3+ cells in renal tissue from LN patients compared to AAV, suggesting that Tregs may be differently involved in the control of inflammatory mechanisms in these diseases. These findings could have further implication for therapeutic approaches aiming at restoring the immunological tolerance. Key Points • Foxp3+-cells are present in larger amount in renal tissue in lupus nephritis vs. ANCA-associated vasculitis. • Our data suggest that Foxp3+ regulatory T cells are involved in the control of inflammatory processes in lupus nephritis.
Topics: Humans; Lupus Nephritis; Kidney Glomerulus; Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis; Biopsy; Forkhead Transcription Factors; Kidney
PubMed: 37368057
DOI: 10.1007/s10067-023-06676-8 -
International Urology and Nephrology May 2024The present study aimed to investigate the effects of α-Klotho and oxidative stress markers on urinary stone disease (USD) and demonstrate their use as biochemical...
PURPOSE
The present study aimed to investigate the effects of α-Klotho and oxidative stress markers on urinary stone disease (USD) and demonstrate their use as biochemical markers in USD.
METHODS
Among the 90 individuals included, 30 individuals were healthy controls (Group 1), 30 individuals presented with USD for the first time (Group 2), and 30 individuals demonstrated recurrent USD (Group 3). Serum levels of α-Klotho, vitamin D, malondialdehyde (MDA), total oxidant status, and total antioxidant status were determined using spectrophotometry analysis. Serum calcium and parathormone levels and 24-h urine calcium levels were measured via biochemical analysis.
RESULTS
No significant intergroup difference was noted in terms of age and sex. The groups had significant differences regarding α-Klotho, oxidative stress index (OSI), MDA, and 24-h urine calcium levels. α-Klotho was a determinant of 24-h urine calcium level and OSI. An increase of 1 pg/mL in α-Klotho level appeared to result in a decrease of 8.55 mg in 24-h urine calcium level and a decrease of 0.04 Arbitrary Unit in OSI. In patients experiencing USD for the first time, α-Klotho values were < 21.83 pg/mL and showed 66% sensitivity and 64% specificity. In individuals with recurrent stone formation, α-Klotho values below 19.41 pg/mL had 60% sensitivity and 77% specificity.
CONCLUSIONS
The biochemical markers investigated herein, i.e., α-Klotho, OSI, and MDA, were involved in the pathogenesis of stone formation and can be used in day-to-day clinical practices of urology clinics to identify patients at risk for both first time and recurrent USD.
Topics: Humans; Klotho Proteins; Calcium; Vitamin D; Urolithiasis; Urinary Calculi; Oxidative Stress; Vitamins; Biomarkers; Recurrence
PubMed: 38194188
DOI: 10.1007/s11255-023-03929-y -
Neural Networks : the Official Journal... Feb 2024Adjoint operators have been found to be effective in the exploration of CNN's inner workings (Wan and Choe, 2022). However, the previous no-bias assumption restricted...
Adjoint operators have been found to be effective in the exploration of CNN's inner workings (Wan and Choe, 2022). However, the previous no-bias assumption restricted its generalization. We overcome the restriction via embedding input images into an extended normed space that includes bias in all CNN layers as part of the extended space and propose an adjoint-operator-based algorithm that maps high-level weights back to the extended input space for reconstructing an effective hypersurface. Such hypersurface can be computed for an arbitrary unit in the CNN, and we prove that this reconstructed hypersurface, when multiplied by the original input (through an inner product), will precisely replicate the output value of each unit. We show experimental results based on the CIFAR-10 and CIFAR-100 data sets where the proposed approach achieves near 0 activation value reconstruction error.
Topics: Deep Learning; Image Processing, Computer-Assisted; Algorithms
PubMed: 37977090
DOI: 10.1016/j.neunet.2023.11.009 -
Nature Communications Jun 2024We introduce Ultra-Flexible Tentacle Electrodes (UFTEs), packing many independent fibers with the smallest possible footprint without limitation in recording depth using...
We introduce Ultra-Flexible Tentacle Electrodes (UFTEs), packing many independent fibers with the smallest possible footprint without limitation in recording depth using a combination of mechanical and chemical tethering for insertion. We demonstrate a scheme to implant UFTEs simultaneously into many brain areas at arbitrary locations without angle-of-insertion limitations, and a 512-channel wireless logger. Immunostaining reveals no detectable chronic tissue damage even after several months. Mean spike signal-to-noise ratios are 1.5-3x compared to the state-of-the-art, while the highest signal-to-noise ratios reach 89, and average cortical unit yields are ~1.75/channel. UFTEs can track the same neurons across sessions for at least 10 months (longest duration tested). We tracked inter- and intra-areal neuronal ensembles (neurons repeatedly co-activated within 25 ms) simultaneously from hippocampus, retrosplenial cortex, and medial prefrontal cortex in freely moving rodents. Average ensemble lifetimes were shorter than the durations over which we can track individual neurons. We identify two distinct classes of ensembles. Those tuned to sharp-wave ripples display the shortest lifetimes, and the ensemble members are mostly hippocampal. Yet, inter-areal ensembles with members from both hippocampus and cortex have weak tuning to sharp wave ripples, and some have unusual months-long lifetimes. Such inter-areal ensembles occasionally remain inactive for weeks before re-emerging.
Topics: Animals; Neurons; Electrodes, Implanted; Brain; Hippocampus; Male; Rats; Signal-To-Noise Ratio; Action Potentials; Mice; Prefrontal Cortex
PubMed: 38844769
DOI: 10.1038/s41467-024-49226-9 -
MedRxiv : the Preprint Server For... Apr 2024Active cigarette smoking leads to increased CXCL5 production. CXCL5 mediates the immune response by attracting immune cells to areas of inflammation. Elevated CXCL5...
BACKGROUND
Active cigarette smoking leads to increased CXCL5 production. CXCL5 mediates the immune response by attracting immune cells to areas of inflammation. Elevated CXCL5 levels are associated with various inflammatory diseases and tumorigenesis. In addition, smoking is linked to an increase in the level of the cytokine CEACAM6 in the bloodstream of smokers. CEACAM6 is increased in pancreatic adenocarcinoma, breast cancer, non small cell lung cancer, gastric cancer, colon cancer and other cancers and promotes tumor progression, invasion, and metastasis. Although cytokine secretion in the innate immune response returns to nonsmoker levels after quitting smoking, the effects on the adaptive response appear to persist for years or decades due to epigenetic memory. As a result, epigenetic changes induced by smoking may contribute to long-lasting alterations in immune function, including elevated CXCL5 and CEACAM6. The effects of cannabis smoking might be similar.
METHODS
In the current study we used UK Biobank (UKB) data to assess the relationship of CXCL5, CEACAM6, and pulmonary function to cigarette and cannabis smoking. Our UK Biobank application was approved as UKB project 57245 (S.L., P.H.R.). Our analysis included all subjects with smoking and/or marijuana use data in the UK Biobank database. Circulating levels of CXCL5 and CEACAM6 were from UKB Olink data. Individual CXCL5 and CEACAM6 levels are NPX, Normalized Protein expression, Olink arbitrary unit in Log2 scale (Olink Proteomics AB, Uppsala, Sweden; http://www.olink.com).
RESULTS
Current smokers and past smokers had elevated circulating levels of CXCL5 and CECAM6. In multivariate analysis, current, past, or no smoking history was significantly related to CXCL5 level and CECAM6 levels, independent of the effects of age, sex. Frequency of cannabis use had a similar effect. In multivariate analysis, frequency of cannabis use was significantly related to CXCL5 level and CECAM6 levels, independent of the effects of age, sex, and years between last cannabis use and enrollment in study.
CONCLUSION
we can confirm a previous report of epigenetic changes induced by cigarette smoking that may contribute to long-lasting alterations in immune function related to CXCL5 and CEACAM6. In addition, we have found that these same long-lasting smoking alterations in immune function related to CXCL5 and CEACAM6 occur in cannabis smokers, possibly rendering them vulnerable to smoking-related tumors in later life.
PubMed: 38633792
DOI: 10.1101/2024.04.01.24305156 -
Optics Express Sep 2023We correct the error in [Opt. Express30, 3866 (2022)10.1364/OE.450092], Fig. 6(c). The unit of the vertical axis in the figure should be arbitrary units, not dB. All...
We correct the error in [Opt. Express30, 3866 (2022)10.1364/OE.450092], Fig. 6(c). The unit of the vertical axis in the figure should be arbitrary units, not dB. All the conclusions are unchanged after the correction.
PubMed: 37859122
DOI: 10.1364/OE.504612 -
Psychophysiology May 2024Recent evidence indicates that measures of brain functioning as indexed by event-related potentials (ERPs) on the electroencephalogram align more closely to...
Recent evidence indicates that measures of brain functioning as indexed by event-related potentials (ERPs) on the electroencephalogram align more closely to transdiagnostic measures of psychopathology than to categorical taxonomies. The Hierarchical Taxonomy of Psychopathology (HiTOP) is a transdiagnostic, dimensional framework aiming to solve issues of comorbidity, symptom heterogeneity, and arbitrary diagnostic boundaries. Based on shared features, the emotional disorders are allocated into subfactors Distress and Fear. Evidence indicates that disorders that are close in the HiTOP hierarchy share etiology, symptom profiles, and treatment outcomes. However, further studies testing the biological underpinnings of the HiTOP are called for. In this study, we assessed differences between Distress and Fear in a range of well-studied ERP components. In total, 50 patients with emotional disorders were divided into two groups (Distress, N = 25; Fear, N = 25) according to HiTOP criteria and compared against 37 healthy comparison (HC) subjects. Addressing issues in traditional ERP preprocessing and analysis methods, we applied robust single-trial analysis as implemented in the EEGLAB toolbox LIMO EEG. Several ERP components were found to differ between the groups. Surprisingly, we found no difference between Fear and HC for any of the ERPs. This suggests that some well-established results from the literature, e.g., increased error-related negativity in OCD, are not a shared neurobiological correlate of the Fear subfactor. Conversely, for Distress, we found reductions compared to Fear and HC in several ERP components across paradigms. Future studies could utilize HiTOP-validated psychopathology measures to more precisely define subfactor groups.
Topics: Humans; Psychopathology; Fear; Mood Disorders; Evoked Potentials; Comorbidity; Mental Disorders
PubMed: 38073133
DOI: 10.1111/psyp.14500