Latency Of Wave Research Articles

Decoding the spatiotemporal regulation of transcription factors during human spinal cord development

The spinal cord is a crucial component of the central nervous system that facilitates sensory processing and motor performance. Despite its importance, the spatiotemporal codes underlying human spinal cord development have remained elusive. In this study, we have introduced an image-based single-cell transcription factor (TF) expression decoding spatial transcriptome method (TF-seqFISH) to investigate the spatial expression and regulation of TFs during human spinal cord development. By combining spatial transcriptomic data from TF-seqFISH and single-cell RNA-sequencing data, we uncovered the spatial distribution of neural progenitor cells characterized by combinatorial TFs along the dorsoventral axis, as well as the molecular and spatial features governing neuronal generation, migration, and differentiation along the mediolateral axis. Notably, we observed a sandwich-like organization of excitatory and inhibitory interneurons transiently appearing in the dorsal horns of the developing human spinal cord. In addition, we integrated data from 10× Visium to identify early and late waves of neurogenesis in the dorsal horn, revealing the formation of laminas in the dorsal horns. Our study also illuminated the spatial differences and molecular cues underlying motor neuron (MN) diversification, and the enrichment of Amyotrophic Lateral Sclerosis (ALS) risk genes in MNs and microglia. Interestingly, we detected disease-associated microglia (DAM)-like microglia groups in the developing human spinal cord, which are predicted to be vulnerable to ALS and engaged in the TYROBP causal network and response to unfolded proteins. These findings provide spatiotemporal transcriptomic resources on the developing human spinal cord and potential strategies for spinal cord injury repair and ALS treatment.

Electrophysiological variations of Guillain-Barre syndrome in Bangladesh- Hospital based study

Introduction: Guillain-Barre syndrome (GBS) is an immune mediated disorder of peripheral nerves which usually presents by rapidly evolving ascending weakness & mild sensory loss and hypo- or areflexia. Electrodiagnostic study (EDS) is the basis for classification of different subtypes of the disease. EDS also has a crucial role in diagnosis, ruling out of some differential diagnosis like myopathic and motor neuron disorders and confirming the neuropathic nature of GBS. The benefit of immunotherapy is greatest when introduced early. In addition, electrophysiological characteristic can predict the prognosis of patients with GBS. This study was conducted to determine the predominant subtype and electrophysiological pattern of GBS in the context of Bangladesh. Objectives: Objective of this study was to compare the electrophysiological variations among different electrophysiological subtypes of GBS. Methods: It is an observational cross sectional study conducted in Department of Medicine and Neurology, Sir Salimullah Medical College & Mitford Hospital and National Institute of Neuroscience (NINS), Dhaka, over a period of one year & four months. Total 30 patients were selected by purposive sampling technique. Demographic data were collected from the patients and recorded in structured case report form. Clinical examination and relevant investigations were done meticulously. Collected questionnaire were checked to identify any error in data. Data was analyzed with SPSS version 21 software. Result: In this study, maximum numbers of patients 53% were between 21-30 years of age group with mean value 27.47±8.1 years. Male to female ratio was 1.7:1. Frequency of Guillain-Barre syndrome is predominance at middle age group. Commonest presentation was limb weakness (parapledgia or quadripledgia) in 60% patients, paresthesias & numbness (40%), pain (100%) and deviation of mouth (63%) of GBS patients. Cerebrospinal fluid shows a mild pleocytosis (5 to 50 cells/µl) in majority of cases was found in 76% of patients. Whereas elevated CSF Protein (>45 mg/dl) was seen in all GBS patient. Increased distal motor latency (DML) was found in 93% patients, whereas 7% patients had normal DML. In the case of the lower limbs, increased distal motor latency was predominant. Decreased amplitude of sensory nerve action potential (SNAP) was seen in 83% patients while 16% patients had normal. Slowing of motor conduction velocities, decreased amplitude as well as increase in distal motor latencies were observed, being more pronounced in the lower limbs. F-wave was completely absent in 20.0% patients while 20% patients showed decreased conduction velocity with prolonged latency. Sensory nerve action potential revealed that decreased sensory conduction velocity (SCV) was seen in 26%, absent SCV in 10% and normal SCV in 63% patients. Present study demonstrated that Acute inflammatory demyelinating polyneuropathy (AIDP) was the commonest type of Guillain-Barré syndrome, present in 56% of patient. Around 30% of the patients belonged to acute motor axonal polyneuropathy (AMAN) and 13% were acute motor sensory axonal polyneuropathy (AMSAN). Conclusion: In this study AIDP was the most frequent subtype. The characteristic findings supportive of AIDP include prolonged distal motor latencies, reduced conduction velocities, conduction blocks at non-entrapment sites, temporal dispersion and prolonged F wave latencies. J MEDICINE 2024; 25: 11-16

Altered brain function and structure in carpal tunnel syndrome: a systematic review and meta-analysis of structural and functional brain imaging.

This systematic review with a meta-analysis aimed to identify the altered brain structure and function in carpal tunnel syndrome (CTS) by summarizing the literature about magnetic resonance imaging (MRI), functional magnetic resonance imaging (fMRI), and magnetoencephalography (MEG) outcomes compared to healthy controls (HC). CTS is the most common nerve entrapment in the arm associated with altered peripheral and central nociceptive system. PRISMA guidelines were used to report the outcomes. Six databases were searched for relevant literature (Web of Science, Scopus, PubMed, Sage, EBSCO host, and Cochrane). Eligible studies comparing MRI, fMRI, and MEG findings in people with CTS (present for at least 2months) and HC through the following parameters: (1) interdigit cortical separation distance, (2) white and grey matter changes, (3) peak latency of M20 wave and recovery function of N20 from the somatosensory cortex (SI), and (4) surface area of activated digit cortical representation. The results from different studies were pooled and a meta-analysis was done. From 17 included, there was a significant reduction of interdigit cortical separation distance of index-middle and index-little fingers in the CTS (SMD = -0.869, 95% CI (-1.325, -0.413), p-value = 0.000) and (SMD = -0.79, 95% CI (-1.217, -0.364), p-value = 0.000), respectively. Middle-little fingers interdigit separation showed no difference (SMD = -0.2, 95% CI (-0.903, 1.309), p-value = 0.718). There is evidence supporting the altered brain structure and function in CTS as evidenced by reduction of interdigit cortical separation distance, and excessive blurring and disinhibition of SI, with low resting state functional connectivity. Thus, centrally directed therapeutic approaches might complement peripheral treatments.

Supra-Threshold LS CE-Chirp Auditory Brainstem Response in the Elderly

Introduction: Aging deteriorates peripheral and central auditory structures and functions. In elders, for an accurate audiological evaluation, it is important to explore beyond the cochlear receptor. Audiograms provide an estimation of hearing thresholds, while the amplitudes and latencies of supra-threshold auditory brainstem response (ABR) can offer noninvasive measures of the auditory pathways functioning. Regarding ABR, in young populations, level-specific chirp (LS CE-chirp) stimulus has been proposed as an alternative synchronizing method to obtain larger ABR responses than those evoked by clicks. However, the supra-threshold characteristics of chirp evoked ABR, and their association to hearing thresholds is relatively unknown in the elderly. The aim of this study was to evaluate supra-threshold LS CE-chirp ABRs in an aged population by comparing their features with click ABRs, and evaluating their relationship with audiometric hearing thresholds. Methods: We carried out a cross-sectional study to characterize the hearing of 125 adults aged over 65 years. We determined the audiometric hearing thresholds and supra-threshold ABRs elicited by LS CE-chirp and click stimuli at 80 dB nHL. We evaluated associations by means of partial correlations and covariate adjustment. We performed specific frequencies’ analysis and subgroup analysis per hearing level. Results: Wave V responses had significantly shorter latencies and larger amplitudes when elicited by LS CE-chirp as compared to click-evoked responses. Audiometric hearing thresholds correlated with age, but ABR characteristics did not. We found mild correlations between hearing thresholds and ABR characteristics, predominantly at higher frequencies and with chirp. We found scarce evidence of correlation between ABR characteristics and the average of behavioral hearing thresholds between 0.5 to 4 kHz (0.5–4 kHz PTA). After subgroup analysis according to the hearing level, no stronger or more significant correlations were found between ABR characteristics and 0.5–4 kHz PTA. Discussion: In this study, we found that supra-threshold LS CE-chirp ABR presented some of the previously described similitudes and differences with supra-threshold click ABR in younger populations. Although, the average amplitude and latency of wave V evoked by LS CE-chirp were larger and faster than those evoked by clicks, these results should be taken with caution at the individual level, and further studies are required to state that LS CE-chirp ABRs are better than click ABRs in elders for clinical evaluations. We did not find consistent associations between hearing thresholds and supra-threshold wave V features, suggesting that these measures should be considered independently in the elderly.

Avaliação do processo maturacional auditivo em crianças portadoras da síndrome da infecção congênita pelo Zika vírus

ABSTRACT Purpose: to analyze the absolute latencies of waves I. III and V and the interpeak intervals I-III. III-V and I-V of the ABR recorded from different age groups of children with congenital zika virus infection and their peers without risk indicators for hearing impairment. Methods: 84 newborns and infants (N=51 study group and N=33 control group) divided into groups with different post-conceptual ages. with the results of their hearing exams analyzed by age group and compared with their peers without other risk indicators for hearing impairment. The assessment of the auditory pathway was conducted through tympanometry. otoacoustic emissions and auditory brain stem responses. Results: only the latency of wave I and the interpeak III-V showed no significant difference between the study and control groups. The absolute latency and interpeak values found in the study group were significantly lower than those found in the control group. Conclusion: the maturation of the brain stem in children with ZIKV infection occurred within normal limits. with no retrocochlear disorders until the age of 5 years.

Blindness as a presenting feature of leptospiral infection: A case report and review of literature

Leptospira is an emerging cause of acute febrile illness in India, which is acquired through contact of skin with contaminated water and soil. Generally, leptospirosis has mild, self-limiting course; rarely, multiple organ dysfunction can occur like aseptic meningitis (20%) and Weil’s disease (10%). Here, we report a case of bilateral optic neuritis in a girl child who presented with blindness following Leptospira infection. On ophthalmological examination, she could appreciate hand movements close to face and had afferent pupillary defect bilaterally. Fundoscopy showed normal fundus with no signs of disc edema. Magnetic resonance imaging (MRI) of brain and orbit showed bilateral hyperintensities in the optic nerve. Visual evoked potential showed prolonged latency in p100 wave in both eyes, suggestive of bilateral optic neuritis. She was diagnosed with Leptospira infection with aseptic meningitis and retrobulbar optic neuritis. She was treated conservatively. She responded well with improvement of visual acuity to 6/6 at the time of discharge.

Infants with neonatal Chronic Lung Disease are associated with delayed auditory conduction in the rostral brainstem after term

AimsVery Low Birthweight (VLBW) infants with neonatal Chronic Lung Disease (CLD) have been found to have functional impairment of the brainstem auditory pathway at term. This study investigated the functional status of the brainstem auditory pathway in VLBW infants with CLD after term for any abnormality. MethodsFifty-two VLBW infants were recruited at 50 weeks of Postconceptional Age: 25 with neonatal CLD and 27 without CLD. None had any other major complications to minimize confounding effects. Brainstem Auditory Evoked Responses were studied at 21‒91/s click rates. ResultsCompared with those without CLD, VLBW infants with CLD had relatively shorter latencies of BAER waves I and III, associated with a slightly lower BAER threshold. Wave V latency and I‒V interpeak interval did not differ significantly between the two groups of infants. The I‒III interval in infants with CLD was shorter than in those without CLD at 91/s clicks. However, the III‒V interval was significantly longer than in those without CLD at all click rates (all p < 0.05). There were no significant differences in the amplitudes of BAER wave components between the two groups of infants. ConclusionsThe main BAER abnormality in VLBW infants with CLD was a prolonged III‒V interval. Auditory conduction is delayed or impaired at more central regions of the brainstem in CLD infants. After term central auditory function is adversely affected by neonatal CLD. Monitoring post-term change is required to provide valuable information for post-term care of CLD infants.

Study of VEP in Ethambutol Optic Neuropathy: A Cross-sectional Study

Introduction: One important first-line drug for treating Tuberculosis (TB) is Ethambutol (EMB), which carries a builtin risk of causing optic neuropathy, potentially resulting in permanent visual impairment. The subjective tests currently used in the diagnostic process, such as visual acuity and visual field assessments, may overlook early changes in visual function. The purpose of the present study is to investigate how well Visual Evoked Potentials (VEP) work as an evaluation tool for identifying optic neuropathy. Aim: To assess the utility of VEP in detecting subtle changes in visual function due to EMB-induced optic neuropathy. Materials and Methods: The cross-sectional study conducted at the Department of Physiology, B.J. Medical College, Ahmedabad, Gujarat, India, over approximately five months (August 2023 to December 2023) involved 62 eyes, with 30 eyes from TB patients undergoing EMB treatment and the rest serving as a control group. VEP recordings were made using a Personal Computers (PC)-based, 2-channel Recorders &amp; Medicare Systems Pvt Ltd Nerve Conduction Velocity (NCV) Electromyography (EMG) Mark II machine with standard silversilver chloride disc electrodes. VEP recordings were conducted regardless of the treatment period and the analysis focused on the amplitude and latency of the P100 wave, a critical component of VEP. Statistical analysis was carried out using Student’s unpaired t-test to compare the results between both groups, with p-values calculated. Results: The mean age of case was 40±17.4 years and controls was 31.12±12.54 years. The study revealed changes in VEP parameters, specifically showing a progressive reduction in P100 amplitude (p-value=0.0001). Conclusion: The present research highlights the potential of VEP as a sensitive and reliable method for assessing EMBinduced optic neuropathy. Incorporating VEP into routine ophthalmologic assessments for patients receiving EMB could improve TB management while reducing the risk of vision loss.

Brainstem auditory evoked potential variability in unmedicated schizophrenic patients

Background: Schizophrenia (SCZ) is one of the most incapacitating and financially disastrous medical conditions and ranks among the most severe and burdensome diseases in the world due to the onset, progression, and frequency of disability. Few researches have been reported that SCZ is linked to a number of neurophysiological abnormalities, including changes in brainstem auditory evoked potentials (BAEPs). Aims and Objectives: The current study aimedto measure brainstem function using BAEPs in patients with SCZ and compare their findings with healthy controls. Materials and Methods: A cross-sectional case–control study was conducted on 51 schizophrenic drug-naive patients selected from the outpatient department of psychiatry, fulfilling the diagnostic criteria of DSM-IV, aged 18-28 years, male and female, with a matching control group of 50 subjects recruited from patients’ relatives. For assessing the severity of SCZ, the positive and negative syndrome scale was utilized. The BAEPs were recorded using a brainstem-evoked response audiometry (BERA) device (NeuroStim-NS 2). Data were analyzed using Independent t-test and Mann–Whitney test based on normality. P-value was considered significant at P &lt; 0.05, P &lt; 0.01 level. Results: A significant difference was observed in patients and control group BAEPs. The absolute latency of waves I and III in the right ear, waves I and V, IPL I-III in the left ear was shown to be significantly different. The results demonstrate that the patient group’s mean latency was higher than the controls. Conclusion: Based on findings, it was concluded that abnormal BAEPs in schizophrenic patients might be attributed to their primary symptom of discontinuity in perceptual and other cerebral functions and slower transmission in the lower brainstem auditory pathway and decreased activity at the brainstem level.

Hearing ability of prairie voles (Microtus ochrogaster).

The hearing abilities of mammals are impacted by factors such as social cues, habitat, and physical characteristics. Despite being used commonly to study social behaviors, hearing of the monogamous prairie vole (Microtus ochrogaster) has never been characterized. In this study, anatomical features are measured and auditory brainstem responses (ABRs) are used to measure auditory capabilities of prairie voles, characterizing monaural and binaural hearing and hearing range. Sexually naive male and female voles were measured to characterize differences due to sex. It was found that prairie voles show a hearing range with greatest sensitivity between 8 and 32 kHz, binaural hearing across interaural time difference ranges appropriate for their head sizes. No differences are shown between the sexes in binaural hearing or hearing range (except at 1 kHz), however, female voles have increased amplitude of peripheral ABR waves I and II and longer latency of waves III and IV compared to males. The results confirm that prairie voles have a broad hearing range, binaural hearing consistent with rodents of similar size, and differences in amplitudes and thresholds of monaural physiological measures between the sexes. These data further highlight the necessity to understand sex-specific differences in neural processing that may underly variability in responses between sexes.

Changes in visual evoked potentials during the menstrual cycle in young women

Background: The visual evoked potential (VEP) is a form of an electrical signal. VEP originates from the visual cortex which is located in Brodman areas 17 and 18 of the occipital lobe. VEP is generated in response to stimulation of the retina by light flashes or pattern stimuli. The advent of VEPs in the 1970s first allowed clinicians to assess neural conduction in the optic nerve. There are many factors that affect VEP such as age and gender; one among them is the hormonal factor. Ovarian and thyroid hormones are vital factors in the generation of olfactory, taste, visual, and auditory neuronal activity. The ovarian hormones progesterone and estrogen play a major role in the conduction of the optic nerve. Aims and Objectives: The aims and objectives of the study are to evaluate the influence of ovarian hormones in the VEPs. Materials and Methods: Among the 1st year medical students, 26 young females (18–20 years of age) were randomly selected. Informed consent was obtained from them and the institutional ethical committee approved the study. Students having regular menstrual periods for the past 6 months with normal visual acuity were included. Those with a history of polycystic ovarian disease, having irregular periods, under hormonal treatment were excluded from the study. Detailed history helps in identifying the proliferative and secretory phases of the menstrual cycle. The P100 wave latency of VEPs was recorded during these two different phases. Results: An unpaired t-test was used for analyzing the data. While comparing the proliferative and secretory phases, P100 wave latency was significantly reduced in the proliferative phase (101±3.6 vs. 97.9 ± 1.43 ms; P &lt; 0.0001). Conclusion: The receptor sensitivity in the visual pathways to dopamine is increased by estrogen which in turn leads to a decrease in the time taken by the visual impulses to reach the visual cortex. Progesterone antagonizes estrogen activity in the central nervous system. Therefore, estrogen is responsible for the reduction in latency during the proliferative phase and progesterone is responsible for the prolonged VEP latency in the secretory phase. Thus, the excitability of the visual system is influenced by the ovarian hormones.

The Effect of Simultaneous Contralateral White Noise Masking on Cortical Auditory Evoked Potentials Elicited by Speech Stimuli.

Introduction Noise obscures speech signal, causing auditory masking. The effects of this masking can be observed through the cortical auditory evoked potentials (CAEPs). White noise, in turn, has an effect on the auditory cortex, interfering, for example, with lexical decision making. Objective To analyze the effect of simultaneous masking by contralateral white noise on CAEPs elicited by speech stimuli. Methods Cross-sectional observational analytical study carried out with 15 participants of both sexes, who were submitted to CAEPs in two conditions: 1) without noise; 2) with white noise at 100 dBSPL intensity, contralaterally and simultaneously. To compare these conditions, the Student t test or the Wilcoxon test were used, depending on the sample normality. Differences with p values < 0.05 were considered significant. Results : When white noise was presented contralaterally and simultaneously to the CAEPs with speech stimulus, an increase in P1, N1 and P2 wave latencies was observed. P1 and P2 amplitudes and N1-P2 peak to peak amplitude also increased, unlike N1 amplitude, which decreased. The differences were significant for P1 and P2 wave latencies and for P2 wave amplitude. Conclusion The simultaneous masking effect was observed from the morphological alterations of the CAEPs with speech stimulus when white noise was presented in the contralateral ear. There was a significant increase in P1 and P2 wave latencies, as well as in P2 wave amplitude.

Mice prone to tinnitus after acoustic trauma show increased pre-exposure sensitivity to background noise.

Noise-induced tinnitus is generally associated with hearing impairment caused by traumatic acoustic overexposure. Previous studies in laboratory animals and human subjects, however, have observed differences in tinnitus susceptibility, even among individuals with similar hearing loss. The mechanisms underlying increased sensitivity or, conversely, resistance to tinnitus are still incompletely understood. Here, we used behavioral tests and ABR audiometry to compare the sound-evoked responses of mice that differed in the presence of noise-induced tinnitus. The aim was to find a specific pre-exposure neurophysiological marker that would predict the development of tinnitus after acoustic trauma. Noise-exposed mice were screened for tinnitus-like behavior with the GPIAS paradigm and subsequently divided into tinnitus (+T) and non-tinnitus (-T) groups. Both groups showed hearing loss after exposure, manifested by elevated audiometric thresholds along with reduced amplitudes and prolonged latencies of ABR waves. Prior to exposure, except for a slightly increased slope of growth function for ABR amplitudes in +T mice, the two groups did not show significant audiometric differences. Behavioral measures, such as the magnitude of the acoustic startle response and its inhibition by gap pre-pulse, were also similar before exposure in both groups. However, +T mice showed significantly increased suppression of the acoustic startle response in the presence of background noise of moderate intensity. Thus, increased modulation of startle by background sounds may represent a behavioral correlate of susceptibility to noise-induced tinnitus, and its measurement may form the basis of a simple non-invasive method for predicting tinnitus development in laboratory rodents.

Intraoperative cochlear nerve monitoring in microvascular decompression of hemifacial spasm and resection of vestibular schwannoma

Objective: To analyze the application of direct cochlear nerve monitoring technology-cochlear nerve action potential (CNAP) monitoring in resection of vestibular schwannoma (VS) and to compare with which in microvascular decompression (MVD) of hemifacial spasm (HFS), in order to provide reference for identification of the cochlear nerve during VS resection surgery and predicting postoperative hearing preservation. Methods: From June 2018 to March 2022, patients with facial spasm and vestibular schwannoma who underwent retrosigmoid approach surgery at the Chinese PLA General Hospital were collected. Before surgery, there were a total of 11 HFS patients and 30 VS patients. Before surgery, the former had hearing level of class A(AAO-HNS), while the latter had serviceable hearing (AAO-HNS class A-B), with a maximum tumor diameter of≤20 mm. CNAP combined with Auditory Brainstem Response (ABR) monitoring was performed during surgery. SPSS 23.0 software was used to analyze the differences of ABR and CNAP parameters between the two groups. Results: The preoperative ABR test in the VS group showed that the latency of wave V and I-V interval were significantly prolonged compared to the HFS group (t=8.36, P<0.001; t=4.61, P<0.001).In VS group, all tumors were totally removed with preserved facial nerve function (House-Brackmann grade Ⅰ-Ⅱ). The serviceable hearing preservation rate was 63.3%. In the HFS group, the initial CNAP waveforms were triphasic and biphasic, with N1 wave latency of (4.32±0.37) ms and amplitude of 25.20 [15.63, 35.40]μV. The distribution of CNAP waveforms before tumor resection in the VS group was the same as that in the HFS group, and which in the hearing preservation group after surgery was also the same. Compared with the HFS group, the latency of N1 wave was prolonged (t=2.670, P=0.011;t=4.584, P<0.001), and the amplitude of N1 wavein the VS group before tumor resection was lower (Z=-3.001, P=0.003). The amplitude of N1 wave in the hearing preservation group after surgery was 20.20 [6.23, 40.90] μV,which was significantly higher than that before tumor resection (Z=-2.133, P=0.033), but there was no statistically significant difference compared to the HFS group (Z=-0.495, P=0.621). Conclusions: The reference range of CNAP in normal hearing population can be preliminarily obtained by the analysis of CNAP in MVD surgery. The latency of N1 wave in VS patients is prolonged and the amplitude of N1 wave is decreased due to tumor compression. The CNAP waveform combined with the change of N1 wave amplitude can provide reference for intraoperative mapping of the cochlear nerve and prediction of postoperative hearing preservation.

Animacy Processing in Autism: Event-Related Potentials Reflect Social Functioning Skills.

Though previous studies with autistic individuals have provided behavioral evidence of animacy perception difficulties, the spatio-temporal dynamics of animacy processing in autism remain underexplored. This study investigated how animacy is neurally encoded in autistic adults, and whether potential deficits in animacy processing have cascading deleterious effects on their social functioning skills. We employed a picture naming paradigm that recorded accuracy and response latencies to animate and inanimate pictures in young autistic adults and age- and IQ-matched healthy individuals, while also employing high-density EEG analysis to map the spatio-temporal dynamics of animacy processing. Participants' social skills were also assessed through a social comprehension task. The autistic adults exhibited lower accuracy than controls on the animate pictures of the task and also exhibited altered brain responses, including larger and smaller N100 amplitudes than controls on inanimate and animate stimuli, respectively. At late stages of processing, there were shorter slow negative wave latencies for the autistic group as compared to controls for the animate trials only. The autistic individuals' altered brain responses negatively correlated with their social difficulties. The results suggest deficits in brain responses to animacy in the autistic group, which were related to the individuals' social functioning skills.

Abstract 13542: Electrical Delay, LA Electromechanical Delay, and LA Volume Contribute to Increased LA Stiffness in Relatively Elderly Patients With Pulmonary Vein Isolation for Atrial Fibrillation

Background: Atrial dysfunction occurs after pulmonary vein isolation (PVI) for atrial fibrillation (AF), and some reports suggest that electrical conduction delay (ECD) via the Bachmann bundle could be a contributing factor. However, the relationship between ECD in the atria and LA function after PVI remains unclear. The LA reservoir strain (LARS) by speckle-tracking echocardiography (STE) is used to assess LA booster function, with a decrease indicating increased LA stiffness. Purpose: We aim to investigate ECD, LA electromechanical delay (LAEMD), and LA function in patients after PVI for AF. Methods: This single-center retrospective study included 74 patients (Mean age at 70.4 ± 9.1 years, 44 males, left ventricular ejection fraction (LVEF): 62.9 ± 6.8 %, LA volume index: LAVI 39.0 ± 10.8 ml/m 2 ) who were in sinus rhythm at the echocardiographic examination. ECD on the ECG was defined as the presence of biphasic P waves, which were classified into those not observed (group A; n=42), those observed only in III lead (group B; n=23), and those observed in all lower wall leads (II, III, aVF) (group C; n=9). LAEMD was defined as the time interval between the top of the R wave on the ECG and the start of the late diastolic wave (a') on the tissue doppler imaging, and the lateral (a' lateral) and septum (a' septum) time differences (a’ sep-lat time) were calculated. To evaluate the LA function, two-dimensional STE was analyzed. Results: Mean observation period was 19.2 months after PVI. Groups B and C showed significant differences in a' sep-lat time compared to group A. LARS was markedly reduced in all groups (average: 19.0 ± 6.3). LARS and LAVI showed a significant difference between groups A and C. Multivariate analysis of factors leading to LARS showed correlations with a', E/e'. Conclusion: These results suggest that in relatively elderly post-PVI AF patients with preserved LVEF, the ECD and LAEMD as well as LAVI may affect LA function long after PVI and contribute to increased LA stiffness.

Renal and cardiovascular prognostic significance of echocardiographic early diastolic mitral annular velocity in IgA nephropathy.

In chronic kidney disease (CKD), as in IgA nephropathy (IgAN), cardiovascular (CV) mortality and morbidity are many times higher than in the general population, and diastolic dysfunction (LVDD) has prognostic significance as well. Tissue Doppler Echocardiography (TDI) is another method for measuring myocardial contractility and determining diastolic dysfunction. 79 IgAN patients (age 46 ± 11years) with CKD stages 1-3 were investigated and followed for 70 ± 28.7months. Doppler echocardiography was used to measure the E (early) and A (late) waves, as well as the E wave deceleration time (EDT) during mitral inflow. TDI was used to measure early (Ea) and late (Aa) diastolic velocities (lateral and septal basal wall fragment average). From these, we calculated the E/Ea and Ea/Aa ratios. The primary combined endpoints were total mortality, major CV events, and end-stage renal disease, and the secondary endpoints were cardiovascular or renal (eGFR decreased below 15ml/min/1.73 m2 or renal replacement therapy was started). Patients with decreased Ea (< 13cm/s) had significantly more endpoints (20/42 vs. 3/37; p = 0.001) than patients with higher Ea (≥ 13cm/s). The secondary renal endpoints were also significantly higher (p = 0.004). In a multivariate model, the eGFR showed independent correlation with the E/A ratio (r = 0.466; p < 0.01), EDT (r = - 0.270; p < 0.01), Ea/Aa ratio (r = 0.455; p < 0.01), and decreased Ea (r = 0.544; p < 0.01). Independent factors influencing Ea were only EDT by uni- and multivariate regression but age and albuminuria by logistic regression. Decreased Ea measured by TDI seems to be an eligible factor to predict the prognosis of IgA nephropathy. The decreased Ea may be a helpful parameter to identify high-risk CKD patients.

Prospective Matched Case-Control Study of Over-Early P100 Wave Latency in Migraine with Aura.

A sizable portion of the world's population suffers from migraines with aura. The purpose of this research is to describe the findings of a case-control study that was carried out to gain a better understanding of how migraine with aura manifests. The research looked at the P100 delay of the visual-evoked potential in both eyes of 92 healthy people and 44 patients who suffered from migraines with visual aura. All of the participants in the study were recruited from King Fahad University Hospital in Saudi Arabia. Both sets of people had the same ancestry and originated from the same location. Patients who suffered from migraines with aura exhibited a significantly shorter P100 delay in both eyes compared to healthy controls (p = 0.001), which is evidence that their early visual processing was distinct. In order to arrive at these findings, we compared people who suffer from migraines with aura to people who do not suffer from migraines and used them as subjects. These findings contribute to the ongoing attempts to bring the disease under control and provide vitally significant new information regarding the functioning of headaches with auras. The primary focus of study in the future should be on determining the nature of the connection between issues with early visual processing and headaches with aura.

The effect of repeated transcranial magnetic stimulation combined with cognitive rehabilitation training on post-stroke cognitive impairment.

The aim of this study was to explore the effect of repetitive transcranial magnetic stimulation (rTMS) combined with cognitive rehabilitation training on post-stroke cognitive impairment (PSCI). We retrospectively reviewed clinical data from 119 patients with PSCI admitted to our hospital from December 2021 to April 2023, of which 58 received pure cognitive rehabilitation training (control group) and 61 received rTMS combined with cognitive rehabilitation training (observation group). We calculated measures of cognitive function rehabilitation, daily living activity abilities, latency and amplitude of P300 wave of evoked potential, and serum biochemical index levels before and after the intervention in the two groups. After the intervention, the scores of the Montreal Cognitive Assessment (MoCA) scale and Rivermead behavioral memory test (RBMT) had improved in the two groups. Also, the Modified Barthel Index (MBI) scores of the two groups increased after the intervention. The P300 wave latencies in both groups decreased and their amplitudes increased after the intervention. The levels of serum neurotrophin-3 (NT-3) and brain-derived neurotrophic factor (BDNF) in the two groups were higher, and the levels of brain glial fibrillary acidic protein (GFAP) were lower after the intervention. All these improvements were more marked in the observation group than in the control group (all p<0.05). Compared with simple cognitive rehabilitation training, the training combined with rTMS was more effective at restoring cognitive function, improving daily living activity abilities, and improving the treatment outcome of patients with PSCI.

High-dose pharmaceutical-grade biotin in patients with demyelinating neuropathies: a phase 2b open label, uncontrolled, pilot study

BackgroundWe proposed to investigate high-dose pharmaceutical-grade biotin in a population of demyelinating neuropathies of different aetiologies, as a proof-of-concept.MethodsPhase IIb open label, uncontrolled, single center, pilot study in 15 patients (three groups of five patients) with chronic demyelinating peripheral neuropathy, i.e. chronic inflammatory demyelinating polyradiculoneuropathy, anti-myelin-associated glycoprotein neuropathy and Charcot-Marie-Tooth 1a or 1b. The investigational product was high-dose pharmaceutical-grade biotin (100 mg taken orally three times a day over a maximum of 52 weeks.The primary endpoint was a 10% relative improvement in 2 of the following 4 electrophysiological variables: motor nerve conduction velocity, distal motor latency, F wave latency, duration of the compound muscle action potential. The secondary endpoints included Overall Neuropathy Limitations Scale (ONLS) score, Medical Research Council (MRC) sum score, Inflammatory Neuropathy Cause and Treatment (INCAT) sensory sum score, 10-m walk test, 6-min walk test, posturography parameters, and nerve excitability variables.ResultsThe primary endpoint was reached in one patient. In the full population analysis, some secondary endpoints parameters improved: MRC score, INCAT sensory sum score, 6-min walk distance, strength-duration time constant, and rheobase. There was a positive correlation between the improvement in the 6-min walk distance and the strength-duration time constant. Regarding the safety results, 42 adverse events occurred, of which three were of severe intensity but none was considered as related to the investigational product.ConclusionsEven if the primary endpoint was not met, administration of high-dose pharmaceutical-grade biotin led to an improvement in various sensory and motor parameters, gait abilities, and nerve excitability parameters. The tolerance of the treatment was satisfactory.Trial registrationClinicalTrials.gov Identifier: NCT02967679; date 2016/12/05.