Search Results (287)

Low-load conditioning activity with blood flow restriction has been addressed as an efficient method to enhance an individual’s performance during their main exercise activity. However, the optimal degree of blood flow restriction remains unclear. Therefore, this study investigated the acute effects of low-load conditioning activity with different degrees of blood flow restriction on muscle strength, power, and perceived exertion. Twenty recreationally trained men (20.9 ± 2.3 years) participated in a randomized crossover design including three conditions: control, low-load blood flow restriction at 50%, and 75% of total arterial occlusion pressure. Participants performed squats (three sets of ten reps) followed by isokinetic assessments of the knee flexor and extensor performance at 7 and 10-min post-exercise. The session rating of perceived exertion (SRPE) was recorded 30 min after each session. No significant effects were observed for condition, time, or their interaction on peak torque, total work, or average power (p < 0.05). However, SRPE was significantly higher in the 75% BFR condition compared to both the 50% BFR and control conditions (p < 0.05), with no difference between the 50% BFR and control. These findings suggest that low-load conditioning activity with blood flow restriction does not acutely enhance neuromuscular performance. However, a higher degree of restriction increases perceived exertion. Full article

Background/Objectives: Total knee arthroplasty (TKA) is commonly associated with postoperative muscle atrophy and weakness, while traditional rehabilitation is often limited by pain and patient compliance. Passive blood flow restriction (pBFR) training may offer a safe, low-threshold method to attenuate muscle loss in this early phase. This pilot study examined the feasibility, safety, and early effects of pBFR initiated during hospitalization on muscle mass, swelling, and functional recovery after TKA. Methods: In a prospective, single-blinded trial, 26 patients undergoing primary or aseptic revision TKA were randomized to either a control group (CON: sham BFR at 20 mmHg) or intervention group (INT: pBFR at 80% limb occlusion pressure). Both groups received 50 min daily in-hospital rehabilitation sessions for five consecutive days. Outcomes, including lean muscle mass (DXA), thigh/knee circumference, 6 min walk test (6 MWT), handgrip strength, and patient-reported outcomes, were assessed preoperatively and at discharge, six weeks, and three months postoperatively. Linear mixed models with Bonferroni correction were applied. Results: The INT group showed significant preservation of thigh circumference (p = 0.002), reduced knee swelling (p < 0.001), and maintenance of lean muscle mass (p < 0.01), compared with CON, which exhibited significant declines. Functional performance improved faster in INT (e.g., 6 MWT increase at T3: +23.7%, p < 0.001; CON: −7.2%, n.s.). Quality of life improved in both groups, with greater gains in INT (p < 0.05). No adverse events were reported. Conclusions: Initiating pBFR training on the first postoperative day is feasible, safe, and effective in preserving muscle mass and reducing swelling after TKA. These findings extend prior BFR research by demonstrating its applicability in older, surgical populations. Further research is warranted to evaluate its integration with standard rehabilitation programs and long-term functional benefits. Full article

Low-load resistance training combined with vascular occlusion or hypoxia can increase muscle cross-sectional area (CSA), but the effect of such training on hormonal response and cardiovascular response is less clear. Thirty female netball athletes took part in a 5-week training of knee muscles in which low-load resistance exercise (20% 1-RM) was combined with either an occlusion pressure (KT, n = 10), hypoxic air (HT, n = 10), or no additional stimulus (CT, n = 10). Growth hormones (GHs), cardiovascular parameters, and CSA were measured before and after the training program. Compared to CT, both HT and KT showed a substantial increase in GH release after the first training bout (pre). After 5 weeks of training (post), the release of GH was substantially reduced in all groups. Compared to CT, HT showed a substantial decrease in SP (11.7 ± 11.3%, mean ± 90% CL) over the training period. The reduction in systolic blood pressure (SP) after hypoxic training resulted in a substantial decrease in the rate-pressure product (RPP) by 15.6 ± 9.6%, compared to CT. CSA from HT and KT is likely related to the heightened release of GH found after training. The hypoxic training protocol has a greater cardiovascular benefit than similar resistance training with blood flow restriction. Full article

The temporary or permanent occlusion of cerebral blood vessels results in ischemic stroke (IS). Ischemia per se causes focal neuronal damage, and the subsequent ischemia–reperfusion injury that occurs after blood flow restoration further compromises brain tissue and cells in the neurovascular unit, significantly contributing to poor patient outcomes and functional impairments. Current research indicates that the ubiquitin–proteasome system (UPS) plays a crucial role in the pathological processes associated with cerebral ischemia–reperfusion injury (CIRI). Notably, E3 ubiquitin (Ub) ligases, which are essential in the UPS, have garnered increasing attention as potential novel therapeutic targets for treating ischemia–reperfusion damage in the brain. This review focuses primarily on the background of E3 Ub ligases and explores their intricate relationships with the pathological processes of CIRI. Full article

Medical Infrared Thermography (MIT) is a safe, non-invasive technique for assessing temperature changes on the skin’s surface that may reflect pathological processes in the underlying tissues. In temporomandibular joint disorders (TMDs), which are often associated with reduced mobility and muscle overactivity, tissue metabolism and blood flow may be diminished, resulting in localized hypothermia. Aim: The purpose of this study was to evaluate muscle tone in the masseter, suprahyoid, and sternocleidomastoid muscles following the application of two types of occlusal splints, a Michigan splint and a double repositioning splint, based on temperature changes recorded using a Fluke Ti401 PRO thermal imaging camera. Materials and Methods: Sixty dental students diagnosed with TMDs were enrolled in this study. After applying the inclusion and exclusion criteria, participants were randomly assigned to one of two groups. Group M received a Michigan splint, while group D was treated with a double repositioning splint. Results: The type of occlusal splint influenced both temperature distribution and muscle tone. In the double repositioning splint group, temperature decreased by approximately 0.8 °C between T1 and T3, whereas in the Michigan splint group, temperature increased by approximately 0.7 °C over the same period. Conclusions: Occlusal splint design has a measurable impact on temperature distribution and muscle activity. The double repositioning splint appears to be more effective in promoting short-term muscle relaxation and may provide relief for patients experiencing muscular or myofascial TMD symptoms. Full article

Background/Objectives: Assessment of the hemodynamic status of the brain in patients with cerebrovascular diseases is crucial for providing valuable clinical information. Various magnetic resonance perfusion sequences are used in studies, and one of the current challenges is comparing methods utilizing exogenous and endogenous contrast. This meta-analysis aimed to evaluate the correlation between arterial spin labeling (ASL)-derived perfusion parameters and those obtained by dynamic susceptibility contrast (DSC) perfusion in stroke and steno-occlusive diseases. Methods: A systematic review and meta-analysis were conducted, including 14 studies that reported correlation coefficients between perfusion MRI sequences in the assessment of stroke or steno-occlusive diseases. The correlation between ASL-derived cerebral blood flow (ASL-CBF) and DSC-derived cerebral blood flow (DSC-CBF) was analyzed, considering different magnetic field strengths (1.5 T and 3.0 T), sequence types, and brain regions. Additionally, real and normalized data were compared. Results: A moderate positive correlation was found between ASL-CBF and DSC-CBF (R = 0.464). Subgroup analysis demonstrated that ASL-CBF and DSC-CBF correlated at 3.0 T (R = 0.401) and 1.5 T (R = 0.700). No significant differences were observed in correlation coefficients based on sequence type or brain region. Normalized data demonstrated a higher correlation coefficient compared to real data (Rreal = 0.393, Rnorm = 0.496). Additionally, the correlation coefficient between ASL-CBF and DSC-derived mean transit time (DSC-MTT) for all included studies was R = −0.422. Conclusions: ASL-derived perfusion parameters demonstrate moderate-to-high agreement with DSC perfusion parameters in stroke and steno-occlusive patients. These findings support the potential utility of ASL as a non-invasive alternative to DSC perfusion imaging in clinical and research settings. Full article

Pericytes, specialized mural cells surrounding microvessels, play a crucial role in maintaining vascular homeostasis and function across various organs, including the eye. These versatile cells regulate blood flow, support the integrity of the blood–retinal barrier, and contribute to angiogenesis. Recent advancements in molecular and cellular biology have revealed the heterogeneity of pericytes and their critical involvement in ocular physiology and pathology. This review provides a comprehensive analysis of pericyte functions in ocular health and their implications in diseases such as diabetic retinopathy, age-related macular degeneration, glaucoma, and retinal vein occlusion. Pericyte dysfunction is implicated in vascular instability, neurovascular coupling failure, inflammation, and pathological neovascularization, contributing to vision-threatening disorders. The review further explores recent findings on pericyte-targeted therapies, including pharmacological agents, gene therapy, and cell-based approaches, aiming to restore pericyte function and preserve ocular health. Full article

Blood flow restriction exercise (BFRE), which partially restricts arterial inflow and occludes venous outflow to the limbs, has gained attention for its potential to elevate serum brain-derived neurotrophic factor (BDNF), a key mediator in the muscle–brain crosstalk leading to improvement of neuroplasticity, neurogenesis, and cognitive health. In this systematic review of five studies, participants included healthy young adults, older adults, and individuals with clinical conditions. Most investigations found that BFRE increased serum BDNF, with responses comparable to those elicited by high-intensity exercise. Proposed mechanisms center on the metabolic demands of BFRE, which may increase lactate and thereby trigger BDNF release. However, two studies showed no significant changes, possibly due to short exercise duration, insufficient training intensity, or age-related reductions in BDNF responsiveness. The small sample sizes and varied protocols across studies limit definitive conclusions. Nonetheless, BFRE may provide a valuable alternative for populations who cannot tolerate high mechanical loads, and it shows promise for enhancing neurotrophic support and potentially improving brain health. Larger, well-controlled trials are warranted to refine BFRE protocols and better understand optimal strategies for increasing BDNF and supporting neuroplasticity. Full article

Background/Objectives: As aging leads to a decline in muscle mass, strength, and functional capacity, identifying effective, low-risk interventions for older adults is essential. Blood flow restriction training (BFRT) has gained recognition as a potential substitute for traditional high-load resistance training, offering comparable benefits with reduced mechanical stress. This scoping review explores current BFRT protocols—specifically cuff pressure, training frequency, and duration—and their impact on muscular strength, hypertrophy, and functional capabilities among healthy elderly individuals. Methods: Following PRISMA-ScR and Arksey and O’Malley’s framework, six databases were searched (2010–2024), yielding 13 eligible studies. Data were charted for BFRT parameters, training regimens, and outcomes related to strength, muscle size, and functionality. Risk of bias was assessed using Cochrane guidelines. Results: Low-load BFRT (20–40% 1RM), applied 2–4 times weekly for 6–12 weeks, significantly improved muscle strength, hypertrophy (e.g., quadriceps CSA), and functional performance (e.g., TUG, 6MWT). Cuff pressures ranged from 50 to 80% arterial occlusion pressure (AOP) for the lower limbs and 30–50% above systolic pressure for the upper limbs. Wider cuffs enhanced safety and comfort. BFRT demonstrated comparable or superior outcomes to conventional training in most studies, with minimal adverse effects reported. Conclusions: The existing evidence suggests that BFRT may be a promising intervention for improving muscle health and functionality in older adults; however, future research should focus on standardizing protocols, long-term outcomes, and tailored guidelines to optimize safety and efficacy. Full article

In this study, pharmacotherapies of abdominal compartment syndrome (ACS) and intra-abdominal hypertension (IAH) in animal studies were reviewed from the perspective of ACS/IAH as failed cytoprotection issues, as non-specific injuries, and from the point of view of the cytoprotection concept as resolution. Therefore, this review challenges the unresolved theoretical and practical issues of severe multiorgan failure, acknowledged significance in clinics, and resolving outcomes (i.e., open abdomen). Generally, the reported agents not aligned with cytoprotection align with current pharmacotherapy limitations and have (non-)confirmed effectiveness, mostly in only one organ, mild/moderate IAH, prophylactic application, and provide only a tentative resolution. Contrarily, stable gastric pentadecapeptide BPC 157 therapy, as a novel and relevant cytoprotective mediator having pleiotropic beneficial effects, simultaneously resolves many targets, resolving established disturbances, specifically compression/ischemia (grade III and grade IV), and decompression/advanced reperfusion. BPC 157 therapy rapidly activates collateral bypassing pathways, and, in ACS and IAH, and later, in reperfusion, there is a “bypassing key” (i.e., azygos vein direct blood flow delivery). This serves to counteract multiorgan and vessel failure, including lesions and hemorrhages in the brain, heart, lung, liver, kidney and gastrointestinal tract, thrombosis, peripherally and centrally, intracranial (superior sagittal sinus), portal and caval hypertension and aortal hypotension, occlusion/occlusion-like syndrome, advanced Virchow triad circumstances, and free radical formation acting as a membrane stabilizer and free radical scavenger. Likewise, not only in ACS/IAH resolving, but also in other occlusion/occlusion-like syndromes, this “bypassing key” could be an effect of the essential endothelial cytoprotective capacity of BPC 157 and a particular modulatory effect on the NO-system, and a rescuing impact on vasomotor tone. Full article

Background/Objectives: Jaw deformities affect not only facial aesthetics but also various oral functions. While previous studies have demonstrated that mandibular prognathism (MP) alters masticatory-induced brain blood flow (BBF), the temporal characteristics of these hemodynamic changes have remained unclear. In this cross-sectional observational study, we investigated the following two specific objectives: (1) whether food hardness affects not only the magnitude but also the temporal patterns of BBF changes during mastication and (2) how malocclusion is associated with these temporal hemodynamic responses. Methods: Twenty-six participants with normal occlusion (NORM) and twenty patients with MP participated in this study. BBF was measured using functional near-infrared spectroscopy, while participants chewed soft paraffin or hard gummy candy. Maximum oxygenated hemoglobin (oxy-Hb) values and time-to-peak BBF were analyzed. Results: While food hardness did not significantly affect maximum oxy-Hb within groups, the MP group showed significantly lower responses during hard gummy candy mastication compared to the NORM group. The occlusal contact area exhibited significant positive correlation with maximum oxy-Hb values, while the ANB angle, an indicator of intermaxillary skeletal relationship, showed no significant correlation with BBF parameters. The hard gummy candy/paraffin ratio of maximum oxy-Hb was significantly higher in the NORM group compared to the MP group. Time-to-peak BBF was approximately twice as long for hard gummy candy compared to paraffin in both groups, with no significant differences between groups. Conclusions: These findings reveal that while MP attenuates the magnitude of masticatory-induced BBF, particularly during hard food mastication, the temporal adaptation to increased food hardness is preserved. This dissociation between magnitude and timing effects suggests that intact basic neurovascular coupling mechanisms would be maintained even in the condition of altered masticatory function in a MP subject, which is providing new insights for rehabilitation strategies in orthognathic surgery cases. Full article

Background: Chronic ischemic stroke presents a significant challenge in neurology, with limited therapeutic options available for long-term recovery. During cerebral infarction, anti-inflammatory phenotype microglia/macrophages produce anti-inflammatory cytokines and neurotrophic factors that facilitate the process of brain repair. However, obtaining sufficient anti-inflammatory microglia/macrophages from the human central nervous system is challenging. Bone marrow-derived inducible microglia-like cells (BM-iMGs) with an anti-inflammatory microglial phenotype were explored to induce neuroprotective properties. Here, we transplanted BM-iMGs into the brain of middle cerebral artery occlusion (MCAO) model male mice to explore their potential for treating chronic ischemic stroke. Methods: Bone marrow-derived mononuclear cells (BM-MNCs) were isolated from green fluorescent protein mice and incubated with granulocyte–macrophage colony-stimulating factor (GM-CSF) and IL-4 to induce BM-iMGs with an anti-inflammatory phenotype. BM-iMGs were transplanted into the brains of mice on day 14 after MCAO, and behavioral tests, histology, cerebral blood flow, and gene expression were evaluated. Results: An intracranial injection of BM-iMGs promoted neurobehavioral recovery, reduced neuronal cell loss, suppressed neuroinflammatory astrocytic and microglial responses in the brain, and increased cortical surface cerebral blood flow in MCAO mice. Furthermore, neuroprotective genes were upregulated, whereas proinflammatory genes were downregulated. Conclusions: The intracranial injection of BM-iMG cells shows significant potential as a novel therapy for chronic ischemic stroke. Full article

The application of blood flow restriction (BFR) during resistance exercise enhances muscular adaptations under low-load conditions. However, its acute effects on explosive neuromuscular performance, particularly on kinetic variables such as the rate of force development (RFD), impulse, and peak force remain poorly understood in women. Twenty-five participants underwent randomized sessions under three occlusion conditions (0%, 40%, and 80% limb occlusion pressure), followed by isometric mid-thigh pull (IMTP) assessments at five time points (pre-exercise; post-exercise; and 5, 10, and 15 min post-exercise). Peak force, impulse, and RFD were analyzed across early (0–50 ms), mid (51–150 ms), and late (151–250 ms) time intervals. BFR did not result in statistically significant alterations in RFD or isometric force production at any time or pressure. These findings indicate that acute BFR application, even when volitional fatigue is induced, does not substantially impair neuromuscular function in isometric settings. These findings indicate that acute exposure to BFR, even under fatiguing conditions, does not substantially impair isometric force production or explosive performance in young physically active women. These results support the task-specific and temporally dependent nature of neuromuscular responses to BFR, highlighting the need for population-specific approaches in BFR programming. Full article

Background and Clinical Significance: Carotid stump syndrome (CSS) is a rare and unexpected cause of recurrent ischemic ipsilateral events in the carotid vascular territory despite the demonstrated occlusion of the internal carotid artery (ICA). It is believed to be caused by microemboli due to turbulent blood flow in the patent stump of the occluded ICA that passes through anastomotic channels and retrograde flow into the middle cerebral artery circulation. Case Presentation: We describe the case of a 65-year-old male patient who suffered multiple concurrent transient ischemic attacks (TIAs) with a totally occluded ipsilateral ICA revealed by computed tomography angiography (CTA). He was diagnosed with CSS, which required the safest therapeutic approach. A further investigation with digital subtraction angiography (DSA) was performed, and a trickle of blood flow was observed in the reportedly occluded ICA. The diagnosis of a true ICA occlusion was withdrawn, and a diagnosis of pseudo-occlusion was established, affecting the final treatment strategy. Therefore, the patient underwent an ipsilateral carotid endarterectomy (CEA), and he has remained asymptomatic since then. Conclusions: The differentiation between a pseudo-occlusion and a true ICA occlusion is essential in promptly managing acute recurrent ipsilateral ischemic strokes in the carotid vascular territory. A further investigation with DSA in cases with a totally occluded ICA using CTA is essential for excluding pseudo-occlusions in ipsilaterally symptomatic patients. Full article

Background. Statins appear to be useful in patients with acute ischemic stroke. Our aim was to evaluate the association between premorbid statin treatment and CT perfusion characteristics of acute ischemic stroke. Methods. A retrospective analysis of patients with acute stroke secondary to occlusion of large vessels in the anterior circulation was performed to assess collateral flow, ischemic core volume, and ischemic penumbra using CT angiography and CT perfusion maps. Fisher’s exact test was used to compare baseline characteristics of patients in the two groups. The Wilcoxon rank-sum test for independent groups was used to compare all variables obtained for the two different groups with and without statin use. Results. We identified 61 patients, including 29 treated with statins and 32 not treated with statins before stroke onset matched by age, gender, and vascular risk factors except for hypercholesterolemia. The statin group showed lower National Institutes of health Stroke Scale scores at onset (14 ± 6.1 vs. 16 ± 4.5; p = 0.04) and lower volumes of brain tissue characterized by impaired cerebral blood flow (CBF), cerebral blood volume (CBV), and ${\mathrm{T}}_{\mathrm{m}\mathrm{a}\mathrm{x}}^{9.5-25\mathrm{s}}$; otherwise, no statistically significant difference was found in the volume of the ${\mathrm{T}}_{\mathrm{m}\mathrm{a}\mathrm{x}}^{16-25\mathrm{s}}$ between the two groups. Conclusions. Premorbid statin treatment is associated with a favorable imaging condition of acute ischemic stroke in terms of ischemic core and ischemic penumbra volume. Full article