Development and validation of a nomogram for tracheotomy decannulation in individuals in a persistent vegetative state: A multicentre study.

BACKGROUND: Decannulation for people in a persistent vegetative state (PVS) is challenging and relevant predictors of successful decannulation have yet to be identified. OBJECTIVE: This study aimed to explore the predictors of tracheostomy decannulation outcomes in individuals in PVS and to develop a nomogram. METHOD: In 2022, 872 people with tracheostomy in PVS were retrospectively enrolled and their data was randomly divided into a training set and a validation set in a 7:3 ratio. Univariate and multivariate regression analyses were performed on the training set to explore the influencing factors for decannulation and nomogram development. Internal validation was performed using 5-fold cross-validation. External validation was performed using receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA) on both the training and validation sets. RESULT: Data from 610 to 262 individuals were used for the training and validation sets, respectively. The multivariate regression analysis found that duration of tracheostomy tube placement≥30 days (Odds Ratio [OR] 0.216, 95 % CI 0.151-0.310), pulmonary infection (OR 0.528, 95 %CI 0.366-0.761), hypoproteinemia (OR 0.669, 95 % CI 0.463-0.967), no passive standing training (OR 0.372, 95 % CI 0.253-0.547), abnormal swallowing reflex (OR 0.276, 95 % CI 0.116-0.656), mechanical ventilation (OR 0.658, 95 % CI 0.461-0.940), intensive care unit (ICU) duration>4 weeks (OR 0.517, 95 % CI 0.332-0.805), duration of endotracheal tube (OR 0.855, 95 % CI 0.803-0.907), older age (OR 0.981, 95 % CI 0.966-0.996) were risk factors for decannulation failure. Conversely, peroral feeding (OR 1.684, 95 % CI 1.178-2.406), passive standing training≥60 min (OR 1.687, 95 % CI 1.072-2.656), private caregiver (OR 1.944, 95 % CI 1.350-2.799) and ICU duration<2 weeks (OR 1.758, 95 % CI 1.173-2.634) were protective factors conducive to successful decannulation. The 5-fold cross-validation revealed a mean area under the curve of 0.744. The ROC curve C-indexes for the training and validation sets were 0.784 and 0.768, respectively, and the model exhibited good stability and accuracy. The DCA revealed a net benefit when the risk threshold was between 0 and 0.4. CONCLUSION: The nomogram can help adjust the treatment and reduce decannulation failure. REGISTRATION: Clinical registration is not mandatory for retrospective studies.

The impact of post-stroke fatigue on inpatient rehabilitation outcomes: An observational study.

BACKGROUND: Post-stroke fatigue is a typical complication following stroke. However, existing research primarily focused on its underlying mechanisms, and its impact on rehabilitation outcomes has yet to be uncovered. OBJECTIVE: This study aims to explore the impact of post-stroke fatigue on rehabilitation outcomes during hospitalization. METHOD: This was a prospective multicenter observational study including 46 stroke patients receiving comprehensive rehabilitation treatment. Patients' basic information was recorded upon admission and patients' functional independence was assessed with Functional Independence Measure (FIM) both upon admission and discharge. One week after rehabilitation treatment, fatigue, positivity in daily activity, attention, and memory were assessed. Serum biochemical indicators and levels of C-reactive protein (CRP) were assessed weekly following admission. The pain scores were assessed during the first week of hospitalization to calculate the average. Correlation analysis, linear regression and propensity score matching (PSM) were used to analyze the impact of fatigue on FIM scores at discharge and length of hospital stay. RESULT: The proportion of patients with low fatigue was 39.13% and significant improvement was revealed in FIM scores upon admissions and discharge [(50.67±18.61) vs. (75.13±21.04), P<0.05]. Positivity in daily activity, attention, and age are factors that influence post-stroke fatigue. After PSM, low-fatigue group (Fatigue score< 3) showed significant higher motor function independence at discharge [(54.39 ± 15.42) vs. (41.89 ± 14.90), P<0.05] and shorter hospital stay [(28.54±9.13)d vs. (37.32 ± 9.81)d, P<0.05] than high-fatigue group. There was a significant difference (P<0.05) in level of CRP between the first inpatient week and the third week, with declining trend. CONCLUSION: Post-stroke fatigue can affect the rehabilitation outcomes regarding motor function independence and length of hospital stay.

Uncovering sympathetic nervous system dysfunction in disorders of consciousness via heart rate variability during head-up tilt test.

Few standardized tools are available for evaluation of disorders of consciousness (DOC). The potential of heart rate variability (HRV) during head-up tilt (HUT) test was investigated as a complementary evaluation tool. Twenty-one DOC patients and 21 healthy participants were enrolled in this study comparing clinical characteristics and HRV time- and frequency-domain outcomes and temporal changes during HUT test. During the 1st-5th min of the HUT, DOC group showed a significant increase and decrease in log low frequency (LF) (p = 0.045) and log normalized high frequency (nHF) (p = 0.02), respectively, compared to the supine position and had lower log normalized LF (nLF) (p = 0.004) and log ratio of low-to-high frequency (LF/HF) (p = 0.001) compared to healthy controls. As the HUT continued from the 6th to the 20th min, DOC group exhibited a significant increase in log LF/HF (16th-20th min) (p < 0.05), along with a decrease in log nHF (6th-10th and 16th-20th min) (p < 0.05) and maintained lower log LF, log nLF, and log LF/HF than controls (p < 0.05). 1st-10th min after returning to the supine position, DOC group demonstrated a significant decrease in log nHF (p < 0.01) and increases in log LF/HF (p < 0.01) and had lower log LF (p < 0.01) and log nLF (p < 0.05) compared to controls. In contrast, the control group exhibited a significant decrease in log nHF (p < 0.05) and increase in log LF/HF (p < 0.05) throughout the entire HUT test. Notably, no significant differences were observed when comparing time-domain outcomes reflecting parasympathetic nervous system between the two groups. HRV during HUT test indicated a delayed and attenuated autonomic response, particularly in the sympathetic nervous system, in DOC patients compared with healthy individuals.

Factors and predictive model for malnutrition in poststroke disabled patients: A multicenter cross-sectional study.

BACKGROUND: Although malnutrition has been shown to influence the clinical outcome of poststroke disabled patients, the associated factors and the prediction model have yet to be uncovered. OBJECTIVES: This study aims to assess the current prevalence and factors associated with malnutrition in poststroke disabled patients and establish a prediction model. METHODS: A multicenter cross-sectional survey among Chinese poststroke disabled patients (≥18 y old) was conducted in 2021. Information on patients' basic data, medical history, Barthel Index, dysphagia, and nutritional status was collected. A multivariable logistic regression model was used to identify the factors that influence malnutrition. Nomogram was developed and internal validation was conducted using 5-fold cross-validation. External validation was performed using the data from a preliminary survey. Receiver operating characteristic (ROC) analysis, calibration curves, and decision curve analysis (DCA) were used to analyze the predictive value of the nomogram. RESULTS: Four hundred fifty-seven cases were enrolled, with the prevalence of malnutrition as 71.77%. Age (aOR = 1.039, 95% CI: 1.006-1.078), pulmonary infection (aOR = 4.301, 95% CI: 2.268-14.464), dysphagia (aOR = 24.605, 95% CI: 4.966-191.058), total intake volume (aOR = 0.997, 95% CI: 0.995-0.999), Barthel Index (aOR = 0.965, 95% CI: 0.951-0.980), and nasogastric tube (aOR = 16.529, 95% CI: 7.418-52.518) as nutrition support mode (compared to oral intake) were identified as the associated factors of malnutrition in stroke-disabled patients (P < 0.05). ROC analysis showed that the area under the curve (AUC) for nomogram was 0.854 (95% CI: 0.816-0.892). Fivefold cross-validation showed the mean AUC as 0.829 (95% CI: 0.784-0.873). There were no significant differences between predicted and actual probabilities. The DCA revealed that the model exhibited a net benefit when the risk threshold was between 0 and 0.4. CONCLUSIONS: Age, pulmonary infection, dysphagia, nutrition support mode, total intake volume, and Barthel Index were factors associated with malnutrition in stroke-related disabled patients. The nomogram based on the result exhibited good accuracy, consistency and values.

Dorsal dentate gyrus mediated enriched environment-induced anxiolytic and antidepressant effects in cortical infarcted mice.

Anxiety and depression are the most common mental health disorders worldwide, each affecting around 30% stroke survivors. These complications not only affect the functional recovery and quality of life in stroke patients, but also are distressing for caregivers. However, effective treatments are still lacking. Enriched environment (EE), characterized with novel and multi-dimensional stimulation, has been reported to exert therapeutic effects on physical and cognitive function. In addition, EE also had potential positive effects on emotional disorders after ischemic stroke; however, the underling mechanisms have not been well elucidated. This study aimed to explore the effectiveness of EE on emotional disorders after cerebral ischemia and its underling mechanism. Sensorimotor cortical infarction was induced by photothrombosis with stable infarct location and volume, resulting in motor dysfunction, anxiety and depression-like behaviors in mice, with decreased ALFF and ReHo values and decreased c-fos expression in the infarction area and adjacent regions. Seven days' EE treatment significantly improved motor function of contralateral forelimb and exhibited anxiolytic and antidepressant effects in infarcted mice. Compared to the mice housing in a standard environment, those subjected to acute EE stimulation had significantly increased ALFF and ReHo values in the bilateral somatosensory cortex (S1, S2), dorsal dentate gyrus (dDG), dorsal CA1 of hippocampus (dCA1), lateral habenular nucleus (LHb), periaqueductal gray (PAG), ipsilateral primary motor cortex (M1), retrosplenial cortex (RSC), parietal association cortex (PtA), dorsal CA3 of hippocampus (dCA3), claustrum (Cl), ventral pallidum (VP), amygdala (Amy), and contralateral auditory cortex (Au). Some of, but not all, the ipsilateral brain regions mentioned above showed accompanying increases in c-fos expression with the most significant changes in the dDG. The number of FosB positive cells in the dDG, decreased in infarcted mice, was significantly increased after chronic EE treatment. Chemogenetic activation of dDG neurons reduced anxiety and depressive-like behaviors in infarcted mice, while neuronal inhibition resulted in void of the anxiolytic and antidepressant effects of EE. Altogether, these findings indicated that dDG neurons may mediate EE-triggered anxiolytic and antidepressant effects in cortical infarcted mice.

High-frequency repetitive transcranial magnetic stimulation promotes ipsilesional functional hyperemia and motor recovery in mice with ischemic stroke.

Neurovascular decoupling plays a significant role in dysfunction following an ischemic stroke. This study aimed to explore the effect of low- and high-frequency repetitive transcranial magnetic stimulation on neurovascular remodeling after ischemic stroke. To achieve this goal, we compared functional hyperemia, cerebral blood flow regulatory factors, and neurochemical transmitters in the peri-infract cortex 21 days after a photothrombotic stroke. Our findings revealed that low- and high-frequency repetitive transcranial magnetic stimulation increased the real-time cerebral blood flow in healthy mice and improved neurobehavioral outcomes after stroke. Furthermore, high-frequency (5-Hz) repetitive transcranial magnetic stimulation revealed stronger functional hyperemia recovery and increased the levels of post-synaptic density 95, neuronal nitric oxide synthase, phosphorylated-endothelial nitric oxide synthase, and vascular endothelial growth factor in the peri-infract cortex compared with low-frequency (1-Hz) repetitive transcranial magnetic stimulation. The magnetic resonance spectroscopy data showed that low- and high-frequency repetitive transcranial magnetic stimulation reduced neuronal injury and maintained excitation/inhibition balance. However, 5-Hz repetitive transcranial magnetic stimulation showed more significant regulation of excitatory and inhibitory neurotransmitters after stroke than 1-Hz repetitive transcranial magnetic stimulation. These results indicated that high-frequency repetitive transcranial magnetic stimulation could more effectively promote neurovascular remodeling after stroke, and specific repetitive transcranial magnetic stimulation frequencies might be used to selectively regulate the neurovascular unit.

Effect of Intermittent Oro-Esophageal Tube Feeding in Bulbar Palsy After Ischemic Stroke: A Randomized Controlled Study.

BACKGROUND: Nasogastric tube feeding (NG) has been widely used in patients with bulbar palsy after ischemic stroke but is associated with a significant risk of complications including malnutrition and pneumonia. Intermittent oro-esophageal tube feeding (IOE) can help alleviate these concerns. This study explored the clinical effect of IOE versus NG on nutritional status, swallowing function, stroke-associated pneumonia, and depression in patients with bulbar palsy after ischemic stroke. METHODS: This randomized controlled study included 148 patients with bulbar palsy after ischemic stroke who underwent routine treatment and swallowing rehabilitation training in the Department of Rehabilitation Medicine between July 2017 and July 2019 in China. The participants were randomly divided into the IOE group (n=74) and NG group (n=74) with IOE and NG as nutritional supports, respectively. The primary outcome was nutritional status including (1) body mass index (kg/m2), (2) serum ALB (albumin, g/L), and (3) PA (prealbumin, mg/L). The secondary outcomes were (1) swallowing function including (i) Functional Oral Intake Scale (FOIS) and (ii) Penetration-Aspiration Scale, (2) pneumonia, (3) depression, and (4) adverse events. Statistical analyses for continuous outcomes were performed using t test, Mann-Whitney U test and Wilcoxon signed-rank test and categorical variables using χ2 test. SPSS 21.0 was used for all analysis. RESULTS: There were no significant baseline differences between the 2 groups. After the treatment, the IOE group demonstrated significantly better results compared with the NG group in ALB ([32.71±0.94] versus [32.28±0.81] g/L; P=0.003), PA ([278.15±13.81] versus [270.31±15.08] mg/L; P=0.001], body mass index ([19.77±1.03] versus [19.41±0.98] kg/m2; P=0.002], FOIS (P<0.001), Penetration-Aspiration Scale (P<0.001), stroke-associated pneumonia ([1, 4.05%] versus [26, 35.14%]; P<0.001), depression ([1, 1.35%] versus [44, 59.46%]; P<0.001) and overall less adverse events (reflux, fever, discomfort in the throat; P<0.001). CONCLUSIONS: In patients with dysphagia with bulbar palsy after ischemic stroke who received routine treatment and swallowing rehabilitation training, IOE is safer and more conducive to the improvement of nutritional status, swallowing function, stroke-associated pneumonia, and depression than NG. REGISTRATION: URL: https://www.chictr.org.cn; Unique identifier: ChiCTR-INC-17011741.

Integrin α3 is required for high-frequency repetitive transcranial magnetic stimulation-induced glutamatergic synaptic transmission in mice with ischemia.

BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS) is an effective therapy in post-stroke motor recovery. However, the underlying mechanisms of rTMS regulates long-lasting changes with synaptic transmission and glutamate receptors function (including AMPARs or NMDARs) remains unclear. METHODS: Mice were received 10-Hz rTMS treatment once daily on the third day after photothrombotic (PT) stroke for 18 days. Motor behaviors and the Western blot were used to evaluate the therapeutic efficacy of 10-Hz rTMS in the mice with PT model. Moreover, we used wild-type (WT) and NEX-α3-/- mice to further explore the 10-Hz rTMS effect. RESULTS: We found that 10-Hz rTMS improved the post-stroke motor performance in the PT mice. Moreover, the levels of AMPAR, vGlut1, and integrin α3 in the peri-infarct were significantly increased in the rTMS group. In contrast, 10-Hz rTMS did not induce these aforementioned effects in NEX-α3-/- mice. The amplitude of AMPAR-mediated miniature excitatory postsynaptic currents (EPSCs) and evoked EPSCs was increased in the WT + rTMS group, but did not change in NEX-α3-/- mice with rTMS. CONCLUSIONS: In this study, 10-Hz rTMS improved the glutamatergic synaptic transmission in the peri-infract cortex through effects on integrin α3 and AMPARs, which resulted in motor function recovery after stroke.

Predictors of long-term decannulation in patients with disorders of consciousness.

Purpose: The predictors of tracheostomy decannulation in patients with disorders of consciousness (DOC) are not comprehensively understood, making prognosis difficult. The primary objective of this study was to identify predictors of tracheostomy decannulation in patients with disorders of consciousness (DOC). The secondary aim was to evaluate the feasibility and safety of the modified Evans blue dye test (MEBDT) in tracheostomized DOC patients. Methods: This retrospective study included all patients with disorders of consciousness (DOC) who underwent tracheostomy and were admitted between January 2016 and September 2022. Age, sex, etiology, initial Glasgow coma scale (GCS), initial Coma Recovery Scale-Revised (CRS-R), diagnosis of unresponsive wakefulness syndrome (UWS) or minimal consciousness state (MCS), MEBDT, initial modified Rankin scale (mRS), and initial Functional Oral Intake Scale (FOIS) were collected upon study enrollment. The relationship between clinical characteristics and cannulation status was investigated through a Cox regression model. Results: A total of 141 patients were included in the study. The average age of these patients was 52.5 ± 16.7 years, with 42 (29.8%) being women. During the study period, 86 subjects (61%) underwent successful decannulation. Univariate analysis revealed that decannulated patients exhibited a significantly better conscious state compared to those without decannulation (CRS-R: p < 0.001; GCS: p = 0.023; MCS vs. UWS: p < 0.001). Additionally, a negative modified Evans blue dye test (MEBDT) result was significantly associated with tracheostomy decannulation (p < 0.001). In the multivariate analysis, successful decannulation was associated with a higher level of consciousness (MCS vs. UWS, p < 0.001, HR = 6.694) and a negative MEBDT result (negative vs. positive, p = 0.006, HR = 1.873). The Kaplan-Meier analysis further demonstrated that MEBDT-negative patients and those in the MCS category had a higher probability of decannulation at 12 months (p < 0.001). Conclusion: The findings of this study indicate that a negative MEBDT result and a higher level of consciousness can serve as predictive factors for successful tracheostomy decannulation in DOC patients.

Theta-burst transcranial magnetic stimulation for dysphagia patients during recovery stage of stroke: a randomized controlled trial.

BACKGROUND: The Theta-burst Transcranial Magnetic Stimulation (TBS) is an emerging modality of Repetitive Transcranial Magnetic Stimulation (rTMS). However, the efficacy of TBS on post-stroke recovery-stage patients with dysphagia remains unclear. AIM: To investigate the effect of intermittent theta burst stimulation (iTBS) and continuous theta burst stimulation (cTBS) in post-stroke dysphagia patients within the recovery stage. DESIGN: Randomized controlled double blinded trial. SETTING: Inpatient. POPULATION: Ninety patients with dysphagia after stroke within 1 to 6 months. METHODS: Patients were divided into the supratentorial group and the brainstem group, and both of groups were further divided into three subgroups, including the sham subgroups, the iTBS subgroups, and the cTBS subgroups. Each of subgroups received 30 min of traditional swallowing rehabilitation treatment every day for 4 weeks. In addition, the iTBS subgroups received iTBS over the cortex of the suprahyoid muscles on the affected hemisphere, the cTBS subgroups received cTBS on the unaffected hemisphere, and the sham subgroups received sham stimulation on unilateral hemisphere. Standardized swallowing assessment (SSA), Oral Motor Function Scale (OMFS) and fiberoptic endoscopic examination of swallowing (FEES) were assessed before and after treatments. RESULTS: In the supratentorial group, compared with the sham and cTBS subgroups, the iTBS subgroups showed significant improvement in SSA, OMFS, vocal folds movement, laryngeal sensation, and Rosenbek Penetration-Aspiration Scale (PAS) (P<0.05). In the brainstem group, compared with the sham subgroup, the iTBS subgroup significantly improved SSA, OMFS, Yale Pharyngeal Residue Severity Rating Scale (YPR-SRS) and PAS (P<0.05), and the cTBS subgroup significantly improved SSA, YPR-SRS and PAS (P<0.05). CONCLUSIONS: This study demonstrated that iTBS might be an effective stimulation pattern to improve the overall swallowing function whether in supratentorial stroke patients or brainstem stroke patients. CLINICAL REHABILITATION IMPACT: iTBS seems to be a promising approach for rehabilitation of overall swallowing function in post-stroke patients.

Design and evaluation of a rodent-specific focal transcranial magnetic stimulation coil with the custom shielding application in rats.

Repetitive TMS has been used as an alternative treatment for various neurological disorders. However, most TMS mechanism studies in rodents have been based on the whole brain stimulation, the lack of rodent-specific focal TMS coils restricts the proper translation of human TMS protocols to animal models. In this study, we designed a new shielding device, which was made of high magnetic permeability material, to enhance the spatial focus of animal-use TMS coils. With the finite element method, we analyzed the electromagnetic field of the coil with and without the shielding device. Furthermore, to assess the shielding effect in rodents, we compared the c-fos expression, the ALFF and ReHo values in different groups following a 15 min 5 Hz rTMS paradigm. We found that a smaller focality with an identical core stimulation intensity was achieved in the shielding device. The 1 T magnetic field was reduced from 19.1 mm to 13 mm in diameter, and 7.5 to 5.6 mm in depth. However, the core magnetic field over 1.5 T was almost the same. Meanwhile, the area of electric field was reduced from 4.68 cm2 to 4.19 cm2, and 3.8 mm to 2.6 mm in depth. Similar to this biomimetic data, the c-fos expression, the ALFF and ReHo values showed more limited cortex activation with the use of the shielding device. However, compared to the rTMS group without the shielding application, more subcortical regions, like the striatum (CPu), the hippocampus, the thalamus, and the hypothalamus were also activated in the shielding group. This indicated that more deep stimulation may be achieved by the shielding device. Generally, compared with the commercial rodents' TMS coil (15 mm in diameter), TMS coils with the shielding device achieved a better focality (~6 mm in diameter) by reducing at least 30% of the magnetic and electric field. This shielding device may provide a useful tool for further TMS studies in rodents, especially for more specific brain area stimulation.

An Enriched Environment Promotes Motor Function through Neuroprotection after Cerebral Ischemia.

Stroke seriously affects human health. Many studies have shown that enriched environment (EE) can promote functional recovery after stroke, but the intrinsic mechanisms remain unclear. In order to study the internal mechanisms of EE involved in functional recovery after ischemic stroke and which mechanism plays a leading role in the recovery of limb function after cerebral infarction, key proteins potentially involved in neuronal protection and synaptic remodeling in the ischemic penumbra have been investigated. In this study, adult C57BL/6 mice after permanent middle cerebral artery occlusion (pMCAO) were assigned to the EE and standard housing (SH) groups 3 days after operation. The EE house was spacious that contained a large variety of small toys; the SH was a normal sized cage. Sham-operated mice without artery occlusion were housed under standard conditions and were fed a normal diet. On days 3, 7, 14, and 21, postoperative motor functional recovery was tested using the modified neurological severity score (mNSS) and the Rotarod test. The expression of B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), growth-associated protein-43 (GAP-43), and synaptophysin (SYN) was examined by western blotting and immunofluorescence staining. The motor functional recovery (based on the mNSS and Rotarod test 3, 7, 14, and 21 days post operation) of mice in the EE group improved significantly compared to the SH group. The expression of GAP-43 and SYN and the ratio of Bcl-2/Bax were all upregulated in the EE group compared to the SH group. In addition, we also explored the relationship between neuronal protection and synaptic remodeling in the EE-mediated recovery of limb function after cerebral infarction by correlation analysis. Correlation analysis showed that compared with the increase of Bcl-2/Bax ratio, the increased expression of GAP-43 and SYN was more closely related to the recovery of limb function in ischemic mice. These data support the hypothesis that EE can promote the process of improvement of limb dysfunction induced by ischemic stroke, and this behavior restoration may, via promoting neuroprotection in the ischemic penumbra, be dependent on the regulation of the expression of GAP-43, SYN, Bcl-2, and Bax. A limitation of the study was that we only observed several representative key indicators of synaptic remodeling and neuronal apoptosis, without an in-depth study of the potential mechanisms involved.

Brain Metabolic Connectivity Patterns in Patients with Prolonged Disorder of Consciousness after Hypoxic-Ischemic Injury: A Preliminary Study.

Understanding the patterns of brain glucose metabolism and connectivity in hypoxic-ischemic encephalopathy (HIE) patients with prolonged disorders of consciousness (DOC) may be of positive significance to the accurate assessment of consciousness and the optimization of neuromodulation strategy. We retrospectively analyzed the brain glucose metabolism pattern and its correlation with clinical Coma Recovery Scale-Revised (CRS-R) score in six HIE patients with prolonged DOC who had undergone 18F-deoxyglucose brain positron emission tomography scanning (FDG-PET). We also compared the differences in global metabolic connectivity patterns and the characteristics of several brain networks between HIE patients and healthy controls (HC). The metabolism of multiple brain regions decreased significantly in HIE patients, and the degree of local metabolic preservation was correlated with CRS-R score. The internal metabolic connectivity of occipital lobe and limbic system in HIE patients decreased, and their metabolic connectivity with frontal lobe, parietal lobe and temporal lobe also decreased. The metabolic connectivity patterns of default mode network, dorsal attention network, salience network, executive control network and subcortex network of HIE also changed compared with HC. The present study suggested that pattern of cerebral glucose metabolism and network connectivity of HIE patients with prolonged DOC were significantly different from those of healthy people.

Intermittent theta-burst stimulation improves motor function by inhibiting neuronal pyroptosis and regulating microglial polarization via TLR4/NFκB/NLRP3 signaling pathway in cerebral ischemic mice.

BACKGROUND: Neuronal pyroptosis and neuroinflammation with excess microglial activation are widely involved in the early pathological process of ischemic stroke. Repetitive transcranial magnetic stimulation (rTMS), as a non-invasive neuromodulatory technique, has recently been reported to be anti-inflammatory and regulate microglial function. However, few studies have elucidated the role and mechanism of rTMS underlying regulating neuronal pyroptosis and microglial polarization. METHODS: We evaluated the motor function in middle cerebral artery occlusion/reperfusion (MCAO/r) injury mice after 1-week intermittent theta-burst rTMS (iTBS) treatment in the early phase with or without depletion of microglia by colony-stimulating factor 1 receptor (CSF1R) inhibitor treatment, respectively. We further explored the morphological and molecular biological alterations associated with neuronal pyroptosis and microglial polarization via Nissl, EdU, TTC, TUNEL staining, electron microscopy, multiplex cytokine bioassays, western blot assays, immunofluorescence staining and RNA sequencing. RESULTS: ITBS significantly protected against cerebral ischemia/reperfusion (I/R) injury-induced locomotor deficits and neuronal damage, which probably relied on the regulation of innate immune and inflammatory responses, as evidenced by RNA sequencing analysis. The peak of pyroptosis was confirmed to be later than that of apoptosis during the early phase of stroke, and pyroptosis was mainly located and more severe in the peri-infarcted area compared with apoptosis. Multiplex cytokine bioassays showed that iTBS significantly ameliorated the high levels of IL-1ß, IL-17A, TNF-α, IFN-γ in MCAO/r group and elevated the level of IL-10. ITBS inhibited the expression of neuronal pyroptosis-associated proteins (i.e., Caspase1, IL-1ß, IL-18, ASC, GSDMD, NLRP1) in the peri-infarcted area rather than at the border of infarcted core. KEGG enrichment analysis and further studies demonstrated that iTBS significantly shifted the microglial M1/M2 phenotype balance by curbing proinflammatory M1 activation (Iba1+/CD86+) and enhancing the anti-inflammatory M2 activation (Iba1+/CD206+) in peri-infarcted area via inhibiting TLR4/NFκB/NLRP3 signaling pathway. Depletion of microglia using CSF1R inhibitor (PLX3397) eliminated the motor functional improvements after iTBS treatment. CONCLUSIONS: rTMS could alleviate cerebral I/R injury induced locomotor deficits and neuronal pyroptosis by modulating the microglial polarization. It is expected that these data will provide novel insights into the mechanisms of rTMS protecting against cerebral I/R injury and potential targets underlying neuronal pyroptosis in the early phase of stroke.

Effect of Tongue-Pressure Resistance Training in Poststroke Dysphagia Patients With Oral Motor Dysfunction: A Randomized Controlled Trial.

OBJECTIVES: The aims of the study were to investigate the effect of tongue-pressure resistance training in poststroke dysphagia patients with oral motor dysfunction and to examine the therapeutic value of tongue-pressure resistance training in the oral and pharyngeal phases. DESIGN: Patients were divided into an experimental and a control group. Both groups received 30 mins of traditional swallowing rehabilitation treatment every day for 4 wks. In addition, the experimental group received tongue-pressure resistance training for an extra 20 mins/d. Maximum tongue pressure and fiberoptic endoscopic examination of swallowing were assessed before and after treatments. RESULTS: Compared with the control group, the experimental group showed significant improvement in Functional Communication Measure for swallowing, Oral Motor Function Scale, maximum tongue pressure, Murray Secretion Scale, Rosenbek Penetration-Aspiration Scale, and food residue in pyriform sinuses ( P < 0.05). There was no significant difference in food residue in epiglottic vallecula between both groups ( P > 0.05). CONCLUSIONS: This study demonstrated that tongue-pressure resistance training is an effective approach to improve the overall swallowing function in patients with oral motor dysfunction. The improvement of oral motor function could facilitate the recovery of pharyngeal motor function. Tongue-pressure resistance training seems to have more clearance of residue in piriform sinus than epiglottic vallecula.

High-Intensity Interval Training Improves Physical Function, Prevents Muscle Loss, and Modulates Macrophage-Mediated Inflammation in Skeletal Muscle of Cerebral Ischemic Mice.

Although skeletal muscle is the main effector organ largely accounting for disability after stroke, considerably less attention is paid to the secondary abnormalities of stroke-related skeletal muscle loss. It is necessary to explore the mechanism of muscle atrophy after stroke and further develop effective rehabilitation strategy. Here, we evaluated the effects of high-intensity interval (HIIT) versus moderate-intensity aerobic training (MOD) on physical function, muscle mass, and stroke-related gene expression profile of skeletal muscle. After the model of middle cerebral artery occlusion (MCAO) was successfully made, the blood lactate threshold corresponding speed (S LT) and maximum speed (S max) were measured. Different intensity training protocols (MOD < S LT; S LT < HIIT < S max) were carried out for 3 weeks beginning at 7 days after MCAO in the MOD and HIIT groups, respectively. We found that both HIIT and MOD prevented stroke-related gastrocnemius muscle mass loss in MCAO mice. HIIT was more beneficial than MOD for improvements in muscle strength, motor coordination, walking competency, and cardiorespiratory fitness. Furthermore, HIIT was superior to MOD in terms of reducing lipid accumulation, levels of IL-1ß and IL-6 in paretic gastrocnemius, and improving peripheral blood CD4+/CD8+ T cell ratio, level of IL-10. Additionally, RNA-seq analysis revealed that the differentially expressed genes among HIIT, MOD, and MCAO groups were highly associated with signaling pathways involved in inflammatory response, more specifically the I-kappaB kinase/NF-kappaB signaling. Following the outcome, we further investigated the infiltrating immune cells abundant in paretic muscles. The results showed that HIIT modulated macrophage activation by downregulating CD86+ (M1 type) macrophages and upregulating CD163+ (M2 type) macrophages via inhibiting the TLR4/MyD88/NFκB signaling pathway and exerting an anti-inflammatory effect in paretic skeletal muscle. It is expected that these data will provide novel insights into the mechanisms and potential targets underlying muscle wasting in stroke.

The Muscle Activation Differences in Post-Stroke Upper Limb Flexion Synergy Based on Spinal Cord Segments: A Preliminary Proof-of-Concept Study.

Objective: This study examined the activation difference of muscles innervated by cervical cord 5-6 (C5-C6) and cervical cord 8- thoracic cord 1 (C8-T1) in upper limb flexion synergy after stroke. Methods: Surface electromyography (sEMG) signals were collected during elbow flexion in stroke patients and healthy controls. The study compared normalized activation of two pairs of muscles that could cause similar joint movement but which dominated different spinal cord segments (clavicular part of the pectoralis major, PC vs. Sternocostal part of the pectoralis major, PS; Flexor carpi radialis, FCR vs. Flexor carpi ulnaris, FCU). In each muscle pair, one muscle was innervated by the same spinal cord segment (C5-C6), dominating the elbow flexion and the other was not. The comparison of the activation of the same muscle between patients and healthy controls was undertaken after standardization based on the activation of the biceps brachii in elbow flexion. Results: There was no difference between the PC and PS's normalized activation in healthy controls while the PC's normalized activation was higher than PS in stroke patients during elbow flexion. Similarly, there was no significant difference in normalized activation between FCR and FCU in healthy controls, and the same is true for stroke patients. However, the standardized activation of both FCR and FCU in stroke patients was significantly lower than that in healthy controls. Conclusion: After stroke, the activation of the distal muscles of the upper limb decreased significantly regardless of the difference of spinal cord segments; while the activation of the proximal muscles innervated by the same spinal cord segment (C5-C6) dominating the elbow flexion showed higher activation during flexion synergy. The difference in muscle activation based on spinal cord segments may be the reason for the stereotyped joint movement of upper limb flexion synergy.

Cortical excitability signatures for the degree of sleepiness in human.

Sleep is essential in maintaining physiological homeostasis in the brain. While the underlying mechanism is not fully understood, a 'synaptic homeostasis' theory has been proposed that synapses continue to strengthen during awake and undergo downscaling during sleep. This theory predicts that brain excitability increases with sleepiness. Here, we collected transcranial magnetic stimulation measurements in 38 subjects in a 34 hr program and decoded the relationship between cortical excitability and self-report sleepiness using advanced statistical methods. By utilizing a combination of partial least squares regression and mixed-effect models, we identified a robust pattern of excitability changes, which can quantitatively predict the degree of sleepiness. Moreover, we found that synaptic strengthen occurred in both excitatory and inhibitory connections after sleep deprivation. In sum, our study provides supportive evidence for the synaptic homeostasis theory in human sleep and clarifies the process of synaptic strength modulation during sleepiness.

Differential Changed Excitability of Spinal Motor Neurons Innervating Tibialis Anterior and Peroneus Muscles Cause Foot Inversion After Stroke.

Objective: To study differential post-stroke changes of excitability of spinal motor neurons innervating a group of antagonist muscles of ankle and their effects on foot inversion. Methods: F waves in tibialis anterior (TA) and peroneus muscles (PN) were recorded. The condition of spasticity and foot inversion in stroke patients were also evaluated. The differences of F wave parameters between patients and healthy controls (HC), as well as TA and PN, were investigated. Results: There were natural differences in the persistence of the F waves (Fp) and F/M amplitude ratio (F/M) between TA and PN in HC. Stroke patients showed significantly higher F/M in TA and PN, while there was no difference in Fp comparing to HC. The natural differences in F wave parameters between TA and PN were differentially retained after stroke. The natural difference of the two muscles in Fp remained unchanged and the F/M difference disappeared in those without spasticity or foot inversion, while the Fp difference disappeared and the F/M difference remained in those with spasticity or foot inversion. Conclusion: Based on the natural difference of the number and size of spinal motor neurons innervating TA and PN, their excitability may change differently according to the severity of the stroke, which may be the reason of foot inversion.

Environmental enrichment enhances post-ischemic cerebral blood flow and functional hyperemia in the ipsilesional somatosensory cortex.

Environmental enrichment has been reported to promote functional recovery in an ischemic stroke. However, the underlying mechanism remains unclear. This study aimed to investigate the effect of environmental enrichment treatment on post-ischemic cerebral blood flow and functional hyperemia in the ipsilesional primary somatosensory cortex of rats. With laser speckle imaging, we were able to monitor the resting cerebral blood flow alteration in the middle cerebral artery occlusion model. Both 3- and 28-day post-ischemic infarct volumes were then examined with triphenyltetrazolium chloride and cresyl violet staining, respectively. We found that an exposure to environmental enrichment was associated with higher post-ischemic cerebral blood flow and less brain tissue loss in the ipsilesional primary somatosensory cortex compared with the standard cage environment. Furthermore, environmental enrichment also enhanced the cerebral blood flow response to whisker stimulation in the ipsilesional barrel cortex when measured 28 days after the middle cerebral artery occlusion. Together, the data suggested that an exposure to environmental enrichment promoted the restoration of cerebral blood flow in the ipsilesional cortex and contributed to a better coupling between functional activation and cerebral blood flow change, which might be the possible mechanisms underlying the neuroprotective effects of EE after ischemia.