Effects of Cued and Uncued Swallowing in Patients With Dementia

Purpose: Parameters such as bolus location at swallow onset (BLSO), stage transition duration (STD), pharyngeal transition duration (PTD), pharyngeal response duration (PRD), and pharyngeal phase duration (PPD) often vary between cued and uncued swallowing conditions. Research has demonstrated that cued swallows may offer functional benefits that mitigate pathophysiological processes. However, there are limited data assessing differences between cued and uncued swallows in disordered populations, such as dementia. The purpose of this study was to evaluate if cued swallowing alters swallowing biomechanics in patients living with dementia. Method: Through a retrospective analysis of videofluoroscopic swallow studies (VFSS), 105 swallows from 26 participants living with dementia ( M age = 81 years; 14 women) were analyzed in duplicate by blinded raters using the Analysis of Swallowing Physiology, Events, Kinematics, and Timing method. Only VFSS with at least one cued and one uncued swallow were included in the analysis. Chi-square tests were used to explore differences in BLSO. Repeated-measures analyses of variance (ANOVAs) were used to explore differences in STD, PTD, PRD, and PPD. Results: Results revealed no significant differences in BLSO between cued and uncued swallows for patients living with dementia ( p = .934). Repeated-measures ANOVAs revealed no significant differences between the two types of swallows for STD ( p = .995), PTD ( p = .864), PRD ( p = .807), or PPD ( p = .660). Conclusions: This study suggests that there may be limited benefit to providing cued swallows to individuals living with dementia. Further research should investigate if this is due to impaired cognition and/or changes in motor control to volitionally complete the cued swallow.

Control of G2 phase duration by CDC25B modulates the switch from direct to indirect neurogenesis in the neocortex

During development, cortical neurons are produced in a temporally regulated sequence from apical progenitors, directly, or indirectly through the production of intermediate basal progenitors. The balance between these major progenitors types is determinant for the production of the proper number and types of neurons and it is thus important to decipher the cellular and molecular cues controlling this equilibrium. Here we address the role of a cell cycle regulator, the CDC25B phosphatase, in this process. We show that deleting CDC25B in apical progenitors leads to a transient increase of the production of TBR1+ neurons at the expense of TBR2+ basal progenitors in mouse neocortex. This phenotype is associated with lengthening of the G2 phase of the cell cycle, the total cell cycle length being unaffected. Using in utero electroporation and cortical slice cultures, we demonstrate that the defect in TBR2+ basal progenitor production requires interaction with CDK1 and is due to the G2 phase lengthening in CDC25B mutants. Altogether, this study identifies a new role for CDC25B and the length of the G2 phase in direct versus indirect neurogenesis at early stages of the cortical development.

Upright versus supine MRI: effects of body position on craniocervical CSF flow

Background Cerebrospinal fluid (CSF) circulation between the brain and spinal canal, as part of the glymphatic system, provides homeostatic support to brain functions and waste clearance. Recently, it has been observed that CSF flow is strongly driven by cardiovascular brain pulsation, and affected by body orientation. The advancement of MRI has allowed for non-invasive examination of the CSF hydrodynamic properties. However, very few studies have addressed their relationship with body position (e.g., upright versus supine). It is important to understand how CSF hydrodynamics are altered by body position change in a single cardiac phase and how cumulative long hours staying in either upright or supine position can affect craniocervical CSF flow. Methods In this study, we investigate the changes in CSF flow at the craniocervical region with flow-sensitive MRI when subjects are moved from upright to supine position. 30 healthy volunteers were imaged in upright and supine positions using an upright MRI. The cranio-caudal and caudo-cranial CSF flow, velocity and stroke volume were measured at the C2 spinal level over one cardiac cycle using phase contrast MRI. Statistical analysis was performed to identify differences in CSF flow properties between the two positions. Results CSF stroke volume per cardiac cycle, representing CSF volume oscillating in and out of the cranium, was ~ 57.6% greater in supine (p < 0.0001), due to a ~ 83.8% increase in caudo-cranial CSF peak velocity during diastole (p < 0.0001) and extended systolic phase duration when moving from upright (0.25 ± 0.05 s) to supine (0.34 ± 0.08 s; p < 0.0001). Extrapolation to a 24 h timeframe showed significantly larger total CSF volume exchanged at C2 with 10 h spent supine versus only 5 h (p < 0.0001). Conclusions In summary, body position has significant effects on CSF flow in and out of the cranium, with more CSF oscillating in supine compared to upright position. Such difference was driven by an increased caudo-cranial diastolic CSF velocity and an increased systolic phase duration when moving from upright to supine position. Extrapolation to a 24 h timeframe suggests that more time spent in supine position increases total amount of CSF exchange, which may play a beneficial role in waste clearance in the brain.

Different Effects of Robot-Assisted Gait and Independent Over-Ground Gait on Foot Plantar Pressure in Incomplete Spinal Cord Injury: A Preliminary Study

Background: There is insufficient evidence to establish the optimal treatment protocol for robot-assisted gait training. Objective: This study aimed to analyze the effects of robot-assisted gait and independent over-ground gait on foot pressure and to determine an effective training protocol for improvement of gait pattern in patients with incomplete spinal cord injury due to industrial accidents. Methods: Four patients with incomplete spinal cord injury due to an industrial accident who had gait disturbance underwent measurement of peak foot pressure and stance phase duration using a foot pressure analysis system with robot-assisted gait and independent over-ground gait. Results: The robot-assisted gait condition has lower peak foot pressure and shorter stance phase duration than the independent over-ground gait. Conclusions: In this study, robot-assisted gait was found to limit gait pattern improvement in patients with gait disturbance caused by incomplete spinal cord injury due to industrial accidents. Therefore, future research will be conducted to determine the optimal protocol for robot-assisted gait training for gait pattern improvement.

Relationship between electrical myocardial instability and postinfarction remodeling in patients with ST-segment elevation myocardial infarction

Aim To study the clinical value of markers for myocardial electrical instability in combination with echocardiographic parameters for predicting the risk of cardiovascular complications (CVC) in the postinfarction period.Material and methods This study included 118 patients with ST segment elevation myocardial infarction (STEMI) and hemodynamically significant stenosis of one coronary artery. A percutaneous coronary intervention (PCI) with stenting of the infarct-related artery was performed for all patients. On day 7-9 and at 24 and 48 weeks after the treatment, ECG Holter monitoring was performed, which included analyses of ventricular late potentials, dispersion of QT interval duration, heart rate turbulence (HRT) and variability (HRV), and heart chronotropic load (HCL). At baseline and during postinfarction week 12, all patients underwent echocardiography with calculation of indexes of end-diastolic volume (iEDV) and end-systolic volume (iESV) to verify the signs of left ventricular (LV) myocardial remodeling. The criteria for LV pathological remodeling included increases in iEDV >20 % and/or iESV >15 % at 12 weeks after STEMI. The group without remodeling, R(-), consisted of 79 (67 %) patients and the group with signs of LV pathological remodeling, R(+), consisted of 39 (33 %) patients. Quality of life and achieved endpoints were evaluated during 144 weeks.Results By week 48 in group R(-), the stabilization of electrical processes in the myocardium was more pronounced as indicated by a decrease in HFLA by 12 % (р=0.004) and by a fourfold increase in RMS (р=0.047). Only in this group, the baroreflex sensitivity restored; pathological ТРС decreased from 20 to 5% (p=0.002) by the end of the active treatment. Stabilization of the repolarization phase duration in various parts of the myocardium was more active in patients without pathological remodeling as shown by decreases in disp QTa (р=0.009), disp QTe (р=0.03), sd QTa (р=0.006), and sd QTe (р=0.009). This was not observed in the group R(+). The recovery of vagosympathetic balance due to leveling the sympathetic component also was more effective in the group R(-), which was reflected in increased spectral and temporal HRV indexes (р<0.05). Both groups showed reduced HCL values at 24 weeks (р=0.047 and р=0.006); however, the HCL regression remained also at 48 weeks only in the group R(-) (р=0.006). Group R(-) patients reported higher quality of life (р=0.03) than group R(+) patients. Endpoints were achieved more frequently in the group R(+): 87.1 % vs. 27.8 % (odds ratio, 11.8; 95 % confidence interval, 4.6–30.8; р=0.00001).Conclusion Pathological myocardial remodeling in early postinfarction period is associated with electrophysiological instability of the myocardium, which results in the development of CVC and low quality of life in patients with STEMI.

A Study of Biofeedback Gait Training in Cerebral Stroke Patients in the Early Recovery Phase with Stance Phase as Target Parameter

Walking function disorders are typical for patients after cerebral stroke. Biofeedback technology (BFB) is currently considered effective and promising for training walking function, including in patients after cerebral stroke. Most studies recognize that BFB training is a promising tool for improving walking function; however, the data on the use of highly selective walking parameters for BFB training are very limited. The aim of our study was to investigate the feasibility of using BFB training targeting one of the basic parameters of gait symmetry—stance phase duration—in cerebral stroke patients in the early recovery period. The study included 20 hemiparetic patients in the early recovery period after the first hemispheric ischemic stroke. The control group included 20 healthy subjects. The BFB training and biomechanical analysis of walking (before and after all BFB sessions) were done using an inertial system. The mean number of BFB sessions was nine (from 8 to 11) during the three weeks in clinic. There was not a single negative response to BFB training among the study patients, either during the sessions or later. The spatiotemporal parameters of walking showed the whole syndrome complex of slow walking and typical asymmetry of temporal walking parameters, and did not change significantly as a result of the study therapy. The changes were more significant for the functioning of hip and knee joints. The contralateral hip amplitude returned to the normal range. For the knee joint, the amplitude of the first flexion increased and the value of the amplitude of hyperextension decreased in the middle of the stance phase. Concerning muscle function, the observed significant decrease in the function of m. Gastrocnemius and the hamstring muscles on the paretic side remained without change at the end of the treatment course. We obtained positive dynamics of the biomechanical parameters of walking in patients after the BFB training course. The feasibility and efficacy of their use for targeted correction need further research.

Effect of Intramuscular Administration of Dexamethasone on Shortening of the Duration of Induction of Labor

Background Induction of labor refers to iatrogenic stimulation of uterine contractions to accomplish delivery prior to the onset of spontaneous labor. Induction of labor is undertaken when both of the following criteria are met: Continuing the pregnancy is believed to be associated with greater maternal or fetal risk than intervention to deliver the pregnancy, and there is no contraindication to vaginal birth. Aim of the Work to evaluate the effect of intramuscular administration of dexamethasone on the duration of vaginal delivery in women undergoing induction of labor. Patients and Methods This double-blinded randomized controlled study was conducted on 60 termed pregnant women who were divided into two groups, Dexamethasone group: injected with 2 ml of the product (dexamethasone®) 12 hours before initiation of labor induction and placebo group: injected with 2 ml distilled water 12 hours before initiation of labor induction. The two groups were induced by the same standard protocol. Determination of interval between initiation of induction and beginning of active phase, duration of active phase, duration of 2nd stage and duration 3rd stage have been detected for both groups and statistically analyzed. Results There were significant statistical differences between the two studied groups as regard rate of cervical dilatation. There were high significant statistical differences between the two studied groups as regard duration between initiation of labor induction and beginning of active phase of labor, duration of active phase of labor and duration of second and third stage of labor. Conclusion an intramuscular injection of dexamethasone before labor induction is found to shorten the duration of labor induction by decreasing the interval between the initiation of induction and the beginning of the active phase, duration of active phase and duration of second stage of labor with no observed maternal or neonatal complications.