Significant Difference In Latency Research Articles

Distinguishing Doors and Floors on All Fours: Landmarks as Tools for Vertical Navigation Learning in Domestic Dogs (Canis familiaris)

Spatial navigation allows animals to understand their environment position and is crucial to survival. An animal’s primary mode of spatial navigation (horizontal or vertical) is dependent on how they naturally move in space. Observations of the domestic dog (Canis familiaris) have shown that they, like other terrestrial animals, navigate poorly in vertical space. This deficit is visible in their use of multi-story buildings. To date, no research has been conducted to determine if dogs can learn how to navigate in an anthropogenic vertical environment with the help of a landmark. As such, we herein investigate the effect of the addition of a visual or olfactory landmark on dogs’ ability to identify when they are on their home floor. Subject behaviors toward their home door and a contrasting floor door were compared before and after exposure to a landmark outside of their home door. While subjects initially showed no difference in latency to approach an apartment door on their home or a wrong floor, we found a significant difference in latency to approach the doors in the test trials for subjects who approached the doors in every trial. Other findings are equivocal, but this result is consistent with the hypothesis that dogs can learn to navigate in vertical space.

Biochemical characterization of the human ubiquitous glucose-6-phosphatase in neutrophil granulocytes.

Glucose-6-phosphatase-β (G6PC3) is a ubiquitous phosphatase present in the endoplasmic reticulum, which, unlike G6PC1, is not responsible for maintaining blood glucose level under starvation. Recently, G6PC3 has been shown to play an important role in neutrophil granulocytes, eliminating the toxic metabolite 1,5-anhydroglucitol-6-phosphate. The present study aimed to look for alternative substrates for the enzyme and outline the expression changes in the parts of this multicomponent system during neutrophil granulocyte differentiation. We determined the kinetic characteristics of recombinant human G6PC3 towards different sugar phosphates, and the transport of these compounds was also measured in rat liver microsomes. We found that all investigated sugar phosphates are substrates for G6PC3, although their microsomal transport is much slower than that of glucose-6-phosphate. Using the HL-60 promyelocytic leukemia cell line as an in vitro model system for myeloid differentiation, we found no significant differences in enzyme expression and phosphatase activity latency between undifferentiated and differentiated cells. Our results provide novel insights into the possible role of G6PC3 in the dephosphorylation of alternative sugar phosphates or their metabolites synthesized in the endoplasmic reticulum and confirm the potential feature of the enzyme in the promyelocytic stage as well. These findings contribute to our knowledge of intracellular carbohydrate metabolism of neutrophil granulocytes, which facilitates further research directions to better understand the underlying mechanisms of neutropenias.

F-waves responses derived from low-intensity electrical stimulation: A method to explore split-hand pathogenesis

ObjectivesThe “split-hand syndrome” is a common clinical sign in amyotrophic lateral sclerosis (ALS), being characterized by more severe atrophy of the hand muscles on the radial side of the hand compared to the ulnar side. We aimed to investigate possible physiological differences between relevant hand muscles using low-intensity F-wave stimulation to assess spinal motoneuron excitability. MethodsWe recruited 36 healthy volunteers. F-waves were recorded from the abductor pollicis brevis (APB), first dorsal interosseous (FDI) and abductor digiti minimi (ADM), using 20 supramaximal stimuli followed by 20 stimuli at a low-intensity required to obtain M-waves with 10 % amplitude of maximal CMAP. We evaluated the following F-wave parameters: F-M latency, chronodispersion, persistence, amplitude, F/CMAP amplitude ratio and number of F-wave repeaters (with low-intensity). In 10 subjects, low-intensity stimulation F-waves were compared after 20 and 50 stimuli in each muscle. ResultsLow-intensity stimulation resulted in lower F-wave amplitude and persistence and higher F/CMAP amplitude ratios. There were no significant differences in F-wave latencies and chronodispersion. When comparing the three muscles, we found higher F-wave persistence and F/CMAP amplitude ratios when recording over the ADM and APB compared to the FDI. We also found a higher number of F-wave repeaters in the ADM with low-intensity stimulation. Results from 20 to 50 low-intensity stimuli were similar. DiscussionA small number of low-intensity stimuli is appropriate to study F-wave latencies and chronodispersion. We found differences in some physiological properties of the ADM spinal motoneuron pool compared to other hand muscles.

The early visual processing of faces in a basic classification task: An ERP study of spatial frequency, other-race and other species effect

ABSTRACT This study investigates the neural processing of other-race and other-species faces, using spatial frequencies (SFs) to probe into early visual processing mechanisms. We conducted a basic classification task to reveal fundamental aspects of facial processing without the complexity of higher-order recognition tasks. This approach utilized SFs set at low (LSF, 0.53 cycles per degree [cpd]), broadband (BB), and high (HSF, 2.1 cpd) SFs to examine their impact on the both P100 and N170 components of event-related potentials. Our findings revealed a significant latency difference in the N170 component under HSF conditions, indicating race-specific efficiency in processing fine details between Asian and Caucasian faces. Furthermore, N170 amplitudes were consistently larger for human than monkey faces, with this difference more pronounced in LSF and BB conditions. This finding indicates that the other-species effect in early visual processing is more pronounced in holistic processing (LSF and BB conditions) rather than in fine-detail processing.

Systematic review/meta-analysis on the role of CB1R regulation in sleep-wake cycle in rats.

A systematic review/meta-analysis was conducted to investigate the effect of cannabinoid type-1 receptor (CB1R) regulation on the sleep-wake cycle of rats and to provide new ideas and evidence-based basis for clinical research on the treatment of sleep disorders. We searched Cochrane Library, PubMed, Web of Science, Embase, Chinese Biomedicine Literature Database (CBM), China National Knowledge Infrastructure, WanFang, and VIP databases for relevant papers, about the effects of CB1R agonists/antagonists on sleep-wake cycle in rats, from inception to November 2023. Two reviewers performed study screening, data extraction, and risk of bias assessment using the SYRCLE's risk of bias tool. Meta-analysis was performed using RevMan 5.3 software. Heterogeneity test was performed on the included studies (Test standard α=0.1). I2 value was used to evaluate the heterogeneity. Forest plot was drawn, and p ≤ 0.05 indicates statistically significant difference. A total of 16 trials involving 484 experimental rats were included. The methodological quality evaluation results showed that the overall quality of the included studies was low. The results of the meta-analysis showed that single administration of CB1R agonists could shorten the wakefulness (W) time in the first 6h (h) (standardized mean difference (SMD)=-2.52, 95% confidence interval (CI) (-3.83, -1.22), p=0.0002) and 24h (SMD=-0.84, 95% CI (-1.31, -0.36), p=0.0005) after administration, prolong nonrapid eye movement sleep (NREM) time (SMD=1.75, 95% CI (0.54, 2.95), p=0.005) and rapid eye movement sleep (REM) time (SMD=1.76, 95% CI (0.26, 3.26), p=0.02), and increase REM frequency after administration (SMD=1.67, 95% CI (0.98, 2.35), p<0.00001), these results were all statistically different. There were no significant differences in sleep latency and average duration of REM. Single administration of CB1R antagonists prolonged the first 6h W time after administration (SMD=1.36, 95%CI (0.29, 2.43), p=0.01), shortened the first 6h NREM time (SMD=-1.73, 95% CI (-2.88, -0.57), p=0.003) and REM time (SMD=-2.07, 95% CI (-3.17, -0.96), p=0.0003) after administration, and increased the frequency of W after administration (SMD=3.57, 95% CI (1.42, 5.72), p=0.001). There was no statistical difference in the average duration of W. REM time and REM frequency increased after continuous CB1R agonist withdrawal. According to the existing evidence, CB1R played a pivotal role in regulating the sleep-wake cycle in rats. CB1R agonists tended to reduce W time, increase NREM and REM sleep times, boost REM frequency, and promote sleep. Conversely, CB1R antagonists could increase the duration and frequency of W, shorten NREM and REM sleep times, and promote W.

Effects of simulated gas of thermobaric bomb charge explosion on Tau protein phosphorylation and cognitive function in rats

Objective: To explore the effect of simulated gas of thermobaric bomb charge explosion on cognitive function and the related mechanism of damage. Methods: In January 2022, thirty-two SPF rats were selected and randomly divided into control group, exposed group 1, 2 and 3 (the exposure time of the simulated gas of the explosion of the thermobaric bomb charge was 5 min, 10 min and 15 min, respectively) according to random number table method, with 8 rats in each group. The simulated gas of the explosion of the thermobaric bomb charge were CO 0.15%, CO(2) 3%, NO 0.1%, O(2) 15%, and the rest were N(2). After 30 days of exposure, water maze was used to detect the learning and memory function of rats. Golgi staining was used to observe the number distribution and morphological structure of hippocampal neurons in rats. Western blot was used to detect the expression of Tau-5, pSer262, pSer396, pThr181 and pThr231 proteins in rats. Repeated measure ANOVA was used to compare the design data of repeated measure, one-way ANOVA was used for multi-group mean comparison, and LSD method was used for pound-wise comparison. Results: There were significant differences in the results of repeated measurement ANOVA of the water maze localization navigation test (F=80.98, P<0.001), and there was an interaction between the group and the training days (F=2.16, P=0.022). There were significant differences in escape latency of rats at the 2nd, 3rd, 4th and 5th days among all groups (P<0.05). The results of spatial exploration showed that the frequency of rats crossing the platform was significantly different among all groups (F=4.49, P=0.011). The frequency of rats crossing the platform in exposed group 2 and exposed group 3 was lower than that in control group, and the frequency of rats crossing the platform in exposed group 3 was lower than that in exposed group 1 (P<0.05). With the increase of exposure time, the number of hippocampal neurons decreased, and the dendrite spine density of neurons in CA1 region decreased (P<0.05). Compared with the control group, there was no significant difference in the relative expression level of Tau-5 protein in all exposed groups (P>0.05), but the expression level of pSer262 protein was significantly increased (P<0.05). Compared with the control group, the protein expressions of pSer396, pThr181 and pThr231 in exposed group 2 and exposed group 3 were significantly increased (P<0.05) . Conclusion: The simulated gas of the explosion of the thermobaric bomb charge may contribute to the development of cognitive dysfunction by damaging hippocampal neurons with aberrant phosphorylation of Tau proteins.

The impact of virtual reality and distractors on attentional processes: insights from EEG.

Virtual reality (VR) allows to create controlled scenarios in which the quantity of stimuli can be modulated, as happen in real-life, where humans are subjected to various multisensory-often overlapping-stimuli. The present research aimed to study changes in attentional processes within an auditory oddball paradigm during a virtual exploration, while varying the amount of distractors. Twenty healthy volunteers underwent electroencephalography (EEG) during three different experimental conditions: an auditory oddball without VR (No-VR condition), an auditory oddball during VR exploration without distractors (VR-Empty condition), and an auditory oddball during VR exploration with a high level of distractors (VR-Full condition). Event-related potentials (ERPs) were computed averaging epochs of EEGs and analyzing peaks at 100ms (N100) and 300ms (P300) latencies. Results showed modulation of N100 amplitude in Fz and of P300 amplitude in Pz. Statistically significant differences in latency were observed only for P300 where the latency results delayed from the No-VR to VR-Full. The scalp topography revealed for P100 no significant differences between frequent and rare stimuli in either the No-VR and VR-Empty conditions. However, significant results were found in N100 in VR-Full condition. For P300, results showed differences between frequent and rare stimuli, in every condition. However, this difference is gradually less widespread from No-VR condition to the VR-Full. The emerging integration of VR with EEG may have important implications for studying brain attentional processing.

Evaluation of the audiovestibular system before and after treatment in patients with Idiopathic intracranial hypertension

Background Idiopathic intracranial hypertension (IIH) can affect both hearing and balance due to increased inner ear pressure. Aims/Objectives This study aimed to evaluate the impact of increased inner ear pressure on hearing and balance in patients with IIH using auditory and vestibular tests. Material and Methods Twenty-four IIH patients and 28 healthy controls underwent oVEMP, pure tone audiometry, tympanometry, and acoustic reflex tests pre-lumbar punctures. IIH patients received acetazolamide. Pre- and post-treatment results, tinnitus, and vertigo scores were compared. Post-treatment oVEMP and audiometry results were compared between groups. Results Pre-treatment oVEMP showed a significant left N1 latency difference (p = 0.049). Post-treatment, left ear amplitude (p = 0.035) and both ear amplitude ratios (p = 0.044 and p = 0.047) increased significantly. Audiometry had no significant changes (p < 0.05). Tinnitus and vertigo scores decreased significantly (p ≤ 0.001). Conclusion Prolonged oVEMP latency suggests IIH may impact the brain stem and vestibular nerve, while increased amplitude values indicate peripheral vestibular involvement. IIH affects hearing across all frequencies, especially at 4000 Hz, impacting both hearing and balance. Significance Understanding the effects of IIH on auditory and vestibular functions can guide effective treatments, improving quality of life for patients by addressing both hearing and balance issues.

An observational study of auditory-evoked potential mismatch negativity response in individuals at high genetic risk for schizophrenia

Objectives: This study presents a novel approach by investigating the abnormal mismatch negativity (MMN) found during response to auditory-evoked potential (ERP) in schizophrenia (SZ) patients. Our unique focus is on the genetic high-risk (GHR) for SZ, comparing it with healthy controls (HC). In addition, we aim to illuminate the interrelationship of MMN with socio-occupational functioning in the GHR group, a novel aspect of our research. Material and Methods: We conducted this study with a rigorous methodology, ensuring the reliability and validity of our findings. Thirty first-degree relatives of SZ patients (GHR) who met the inclusion and exclusion criteria were recruited by purposive sampling and compared with thirty HCs. We collected sociodemographic and clinical data from all study participants, which were assessed by the Family Interview of Genetic Studies. GHR was evaluated for current socio-occupation functioning using the Social and Occupational Functioning Assessment Scale (SOFAS). All the participants underwent 128-channel electroencephalographic recording using an auditory-evoked responses paradigm. The MMN was calculated at the frontal electrode clusters, ensuring accurate and reliable data collection. Results: The study revealed a statistically significant difference in frontal MMN latency between GHR and HC. Moreover, a positive relationship was noted between the SOFAS score and MMN amplitude, and a negative relationship was found between the latencies at the frontal region. Conclusion: Our research has made a significant breakthrough in understanding SZ. Our findings reveal that individuals with a genetic susceptibility to SZ exhibit a unique response in a particular test known as MMN. This test measures the automatic auditory change detection mechanism, which detects minor alterations in the acoustic environment and is referred to as MMN. This newfound insight could prove instrumental in developing more effective diagnoses and treatments for SZ.

Peripheral hearing sensitivity is similar between the sexes in a benthic turtle species despite the larger body size of males.

Sexually dimorphic hearing sensitivity has evolved in many vertebrate species, and the sex with a larger body size typically shows more sensitive hearing. However, generalizing this association is controversial. Research on sexually dimorphic hearing sensitivity contributes to an understanding of auditory sense functions, adaptations, and evolution among species. Therefore, the hypothesized association between body size and hearing needs further validation, especially in specific animal groups. In this study, we assessed hearing sensitivity by measuring auditory brainstem responses (ABRs) in both sexes of 3-year-old Chinese softshell turtles (Pelodiscus sinensis). In this species, male bodies are larger than those of female, and individuals spend most of their lives in the mud at the bottom of freshwater habitats. We found that for both sexes, the hearing sensitivity bandwidth was 0.2-0.9 kHz. Although males were significantly larger than females, no significant differences in ABR thresholds or latencies were found between males and females at the same stimulus frequency. These results indicate that P. sinensis hearing is only sensitive to low-frequency (typically <0.9 kHz) sound signals and that sexually dimorphic hearing sensitivity is not a trait that has evolved in P. sinensis. Physiological and environmental reasons may account for P. sinensis acoustic communication via low-frequency sound signals and the lack of sexually dimorphic hearing sensitivity in these benthic turtles. The results of this study refine our understanding of the adaptation and evolution of the vertebrate auditory system.

Role of Oncostatin M in Exercise-Induced Breast Cancer Prevention.

Moderate-to-vigorous-intensity physical activity decreases the risk of breast cancer. The muscle-derived cytokine (myokine), oncostatin M (OSM), has been shown to decrease breast cancer cell proliferation. We hypothesized that OSM is involved in physical activity-induced breast cancer prevention, and that OSM antibody (Anti-OSM) administration would mitigate the effect of physical activity in a rat model of mammary carcinoma. Female Sprague Dawley rats were injected with 50 mg/kg N-methyl-N-nitrosourea to induce mammary carcinogenesis. During the 20-week study, rats were exercise trained (EX) or remained sedentary (SED). Additional groups were treated with Anti-OSM antibody (SED + Anti-OSM and EX + Anti-OSM) to explore the impact of OSM blockade on tumor latency. Exercise training consisted of treadmill acclimation and progressive increases in session duration, speed, and grade, until reaching 30 min/day, 20 m/min at 15% incline. Experimentally naïve, age-matched, female rats also completed an acute exercise test (AET) with time course blood draws to evaluate OSM plasma concentrations. Relative tumor-free survival time was significantly longer in EX animals (1.36 ± 0.39) compared to SED animals (1.00 ± 0.17; p = 0.009), SED + Anti-OSM animals (0.90 ± 0.23; p = 0.019), and EX + Anti-OSM animals (0.93 ± 0.74; p = 0.004). There were no significant differences in relative tumor latency between SED, SED + Anti-OSM, or EX + Anti-OSM animals. Following the AET, OSM plasma levels trended higher compared to baseline OSM levels (p = 0.080). In conclusion, we observed that exercise-induced delay of mammary tumor development was mitigated through Anti-OSM administration. Thus, future studies of the OSM mechanism are required to lay the groundwork for developing novel chemo-prevention strategies in women who are unable or unwilling to exercise.

Neural markers associated with improved tinnitus perception after tinnitus retraining therapy

Objective Tinnitus retraining therapy (TRT) has been widely used in tinnitus management. However, its efficacy is often assessed through subjective methods. Here, we aimed to assess potential neural changes following TRT using mismatch negativity (MMN). Design Chronic tinnitus (>6 months) patients participated in a six-month TRT program. We collected tinnitus psychoacoustic features and gathered the tinnitus handicap inventory (THI) before and after TRT. We also used a multi-featured paradigm, including frequency, intensity, duration, location and silent gap deviants, to elicit MMN response before and after TRT. Data were analyzed retrospectively. Study sample The study involved 26 chronic tinnitus patients. Results Post-TRT measurements showed that MMN amplitudes significantly increased for all deviant conditions (p ≤ .03). However, we did not find a significant difference in MMN latencies for all deviant conditions (p ≥ .13). The THI scores of the patients significantly decreased following the TRT program (p < 0.001). Our results reveal improved subjective tinnitus perception following the TRT program. Conclusion These findings indicate that TRT might be a viable alternative in tinnitus management. The greater MMN amplitudes and improved subjective tinnitus perception raise the possibility that MMN can be a useful tool in tinnitus research and tinnitus patient follow-up.

Variability in sleep architecture and alterations in circadian rhythms in patients with acute cerebral infarction accompanied by sleep-disordered breathing.

To continuously and dynamically monitor the sleep status of patients in the acute phase of cerebral infarction, and to investigate the characteristics of acute cerebral infarction(ACI)associated with sleep-disordered breathing (SDB), variations in sleep structure, and changes in sleep circadian rhythms. Patients with ACI within 48h of onset who were admitted to the Department of Neurology at Kailuan General Hospital from November 2020 to December 2022 were selected. Detailed baseline information such as age, gender, smoking history, drinking history, were recorded for the selected participants. From the beginning of their hospitalization, the selected participants were monitored for their sleep status continuously for 5 days using the Intelligent Mattress-based Sleep Monitoring Platform System(IMSMPS). Based on the heart rate data obtained from the monitoring, the interdaily stability (IS) and intradaily variability (IV) of the sleep circadian rhythm were calculated. 1,367 patients with ACI were selected. Monitoring results over 5 days indicated 147 cases (10.75%) without SDB, and 1,220 cases (89.25%) with SDB. Among the group with SDB, there were 248 cases (18.14%) with continuous mild SDB, 395 cases (28.90%) with moderate SDB, 295 cases (21.58%) with severe SDB, and 282 cases (20.63%) that fluctuated between different severity levels. Within this fluctuating group, 152 cases (53.90%) fluctuated between two severity levels, 120 cases (42.55%) between three levels, and 10 cases (3.55%) among all four levels. There were statistically significant differences (P < 0.05) in the sleep latency, sleep efficiency, non-rapid eye movement stages 1-2, rapid eye movement, proportion of non-rapid eye movement, proportion of rapid eye movement, wake after sleep onset, time out of bed, number of awakenings, respiratory variability index, and heart rate variability index among patients with ACI monitored from day 1 to 5. However, other monitored sleep structure parameters did not show statistically significant differences (P > 0.05). The coefficient of variation for all sleep monitoring parameters ranged between 14.54 and 36.57%. The IV in the SDB group was higher than in the group without SDB (P < 0.05), and the IS was lower than in the group without SDB (P < 0.05). Patients in the acute phase of cerebral infarction have a high probability of accompanying SDB. The sleep structure of these patients shows significant variability based on the onset time of the stroke, and some patients experience fluctuations among different severity levels of SDB. ACI accompanied by SDB can further reduce the IS of a patient's sleep circadian rhythm and increase its IV.

Sleep Patterns Analysis Using Polysomnography: A Comparison Between Active and Sedentary Male

While there is a rising focus on sleep issues among population, a notable gap exists in the comparative analyses of sleep patterns between Active and Sedentary Male. The purpose of this study is to investigate and compare sleep patterns and polysomnography measures between active and sedentary men. Total ten male participants were randomly selected to fulfill the purpose of the study. All the participants were in the age group 18-25 only. The selected variable, i.e. Total sleep time (TST), sleep onset latency (SOL), sleep efficiency (SE) and wake after sleep onset (WASO) was measured by RMS Quest 24/32 channel polysomnography machine. The obtained data were analyzed by applying independent t-test to identify the significant difference. An α-value &lt;0.05 was considered statistically significant. Results indicate that significant difference were found in selected variables as total sleep time (TST) of active and sedentary male, as the p-value (000) was &lt; 0.05, a significant difference in the sleep onset latency (SOL) of active and sedentary male, as the p-value (000) was &lt; 0.05, a significant difference in the wake after sleep onset (WASO) of active and sedentary male, as the p-value (000) was &lt; 0.05, also a significant difference in the sleep efficiency (SE) of active and sedentary male, as the p-value (000) was &lt; 0.05, at 5% level of significance.

Evaluation of Brainstem Auditory-Evoked Potentials in Infants with Iron Deficiency Anemia

Purpose: To evaluate and compare the brain functions of infants with and without Iron Deficiency anaemia (IDA) electrophysiologically with brainstem auditory potentials (BAEPs). Materials and Methods: BAEP tests were performed on 26 healthy infants and 26 infants with iron deficiency anaemia, aged 6-24 months, who were followed through the Paediatric Haematology Department at SDU Faculty of Medicine. Children were classified as anaemic if their haemoglobin (Hb) level fell below -2 standard deviations for their age. All patients diagnosed with iron deficiency anaemia received 5 mg/kg/day of divalent iron glycine sulphate complex in three doses daily for a duration of 12 weeks, to be taken on an empty stomach. Both group were orally administered Chloral hydrate at a dosage of 50mg/kg prior to the BAEP test to induce sedation. The BAEP was recorded at a sound intensity level of 90 decibels, with a frequency of 10 Hertz, and with click stimuli ranging from 1000 to 2000. The BAEP test was administered to the IDA group before and after treatment, as well as to the control group, with a 3-month interval between tests. Results: 14 (53.8%) of the IDA patients were males, and 16 (61.5%) of the control group were females. Patients with IDA had an average age of 14.4±3.09 months, while the control group patients have an average age of 11.2±4.04 months. Patients with iron deficiency anaemia had lower pre-treatment levels of Hb, Hct, MCV, MCH, MCHC, transferrin saturation percentage, and ferritin compared to the control group, whereas platelet and RDW values were greater (p˂0.001). The study compared the Brainstem Auditory Evoked Potential (BAEP) values of patients with Iron Deficiency Anaemia (IDA) before treatment with those of control patients. The results indicated that the III-V interval, showing nerve conduction time, was significantly prolonged in the pre-treatment BAEPs (p˂0.05). There was no significant difference in interpeak latencies between the control group and patients with iron deficiency anaemia (IDA) following therapy (p˂0.05). Significant differences were found in the I-III, III-V, and I-V interpeak latencies of individuals with iron deficiency anaemia before and after treatment (p

Aged HIV-1 Tg26 Transgenic Mice display Vascular Dysfunction with No Alterations in Neurocognitive Function or Cerebral Blood Flow

Although combination antiretroviral therapy (cART) has markedly reduced HIV mortality and increased life expectancy, people living with HIV (PLWH) develop premature cognitive and brain aging, classified as HIV-associated neurocognitive disorder (HAND). Vascular dysfunction and expression of HIV-derived proteins have independently been associated with cognitive impairment without causality being established. Thus, we investigated the role of HIV viral proteins in endothelial dysfunction and cognitive impairment in an aged mouse model of HIV. We used 18-month-old Tg26 mice and their wild-type littermate controls. Tg26 mice express 7 out of the 9 HIV viral proteins under the control of the long-term repeat promoter and have previously been shown to exhibit signs of cognitive impairment at eight months of age. Conduction of concentration-response curves to acetylcholine in mesenteric arteries using wire myography revealed impaired endothelium-dependent relaxation in Tg26 mice compared to WT mice. Measurements of brain perfusion with arterial spin labeling magnetic resonance imaging showed no differences in the whole brain and hippocampal cerebral blood flow. In addition, there were no changes in the hippocampus volume, which has been reported to be reduced with cognitive impairments. Two methods were employed to assess the cognitive abilities of the mice: Morris water maze (MWM) and the IntelliCage system. MWM requires human handling while the IntelliCage system is fully automated enabling the testing of mouse cognitive function during their active period and independently of human handling. Tg26 and WT mice underwent ten days of MWM testing and eight days of IntelliCage testing to assess spatial learning and memory. Tg26 mice showed no significant differences in latency to platform, distance swam to platform, or swim velocity when compared to their WT littermates. The IntelliCage results showed no differences in total visits, total visits with nose pokes, or total licks during the reversal learning period. Additionally, there were no significant differences in percent side error or place error indicating that cognitive function is not impaired in Tg26 mice. The Y-maze test further showed no differences in spontaneous alteration, a measure of spatial working memory. Altogether, our data shows that although 18-month-old female Tg26 mice develop endothelial dysfunction, they display no alterations in cerebral blood flow and no cognitive impairment indicating that systemic viral protein expression and vascular dysfunction might minimally contribute to neurocognitive impairment in HIV. R01HL130301 &amp; R01HL155265 (E.J.B). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Otolithic functions in patients with residual dizziness after successful repositioning manoeuvres for unilateral posterior canal BPPV.

To evaluate otolithic functions in patients with residual dizziness after successful canalith repositioning procedures (CRPs) for unilateral posterior canal benign paroxysmal positional vertigo (BPPV), and to investigate possible risk factors. This case-control observational study included healthy controls and patients with residual dizziness after improvement following CRP for BPPV. All participants were subjected to full history taking, otoscopy, audiological basic evaluation, Dix-Hallpike test to search for posterior canal BPPV, residual dizziness screening, and vestibular evoked myogenic potential (VEMP) testing. Between-group differences were assessed and possible factors associated with residual dizziness were identified by univariate analysis. A total of 50 patients with residual dizziness (mean age, 56.53 ± 7.46 years [29 female: 21 male]) and 50 healthy controls (mean age, 58.13 ± 7.57 years [20 female: 30 male]) were included. A significant difference in VEMP latencies was found between the patient and control group (delayed in the patient group), with no significant between-group difference in amplitude in both ears. Aging, female sex, long duration of BPPV, number of CRPs, cervical VEMP and ocular VEMP abnormalities, and winter onset, were significantly associated with the risk of residual dizziness. Residual dizziness is a frequent sequel of BPPV that may relate to otolithic dysfunction. VEMP changes were revealed in the form of delayed latencies.

Correlation analysis between HLA-DQA1*0102/DQB1*0602 genotypes and narcolepsy patients in China.

At present, the etiology of narcolepsy is not fully understood, and it is generally believed to be an autoimmune reaction caused by interactions between environmental and genetic factors. Human leukocyte antigen (HLA) class II genes are strongly associated with this gene, especially HLA-DQB1*0602/DQA1*0102. In this study, we mainly analyzed the correlation between different genotypes of HLA-DQB1*0602/DQA1*0102 and clinical manifestations in Chinese patients with narcolepsy. Narcolepsy patients who were treated at the Department of Neurology, The First Affiliated Hospital of Shandong First Medical University from January 2021 to September 2023 were selected. General information, sleep monitoring data, cerebrospinal fluid (CSF) orexin levels, and human leukocyte antigen gene typing data were collected. The statistical analysis was performed using SPSS 26.0, and the graphs were drawn using GraphPad Prism 9.5. A total of 78 patients were included in this study. The DQA1 and DQB1 gene loci were detected in 54 patients, and only the DQB1 gene locus was detected in 24 narcoleptic patients. The most common allele at the HLA-DQB1 locus was *0602 (89.7%), and the most common genotype at this locus was *0602*0301 (19.2%), followed by *0602*0602 (17.9%). The most common phenotype of the HLA-DQA1 locus is *0102 (92.6%), and the most common genotype of this locus is *0102*0102 (27.8%), followed by *0102*0505 (14.8%). There were significant differences (p < 0.05) between HLA-DQB1*0602-positive and HLA-DQB1*0602-negative patients in terms of orexin-A levels, presence or absence of cataplexy, UNS, PSG sleep latency, REM sleep latency, N1 sleep percentage, oxygen depletion index, and average REM latency on the MSLT. The HLA-DQA1*0102-positive and HLA-DQA1*0102-negative patients showed significant differences (p < 0.05) in disease course, presence or absence of sudden onset, PSG REM sleep latency, N1 sleep percentage, and average REM latency on the MSLT. There were significant differences in the average REM latency of the MSLT between HLA-DQB1*0602/DQA1*0102 homozygous and heterozygous patients p < 0.05, and no differences were found in the baseline data, orexin-A levels, scale scores, or other sleep parameters. Different genotypes of HLA-DQA1*0102/DQB1*0602 are associated with symptoms of cataplexy in Chinese narcoleptic patients. Homozygous individuals have a shorter mean REM latency in the MSLT, greater genetic susceptibility, and relatively more severe sleepiness.

Implications of depressive mood in OSAHS patients: insights from event-related potential

BackgroundObstructive sleep apnea-hypopnea syndrome (OSAHS) is a chronic breathing disorder characterized by recurrent upper airway obstruction during sleep. Although previous studies have shown a link between OSAHS and depressive mood, the neurobiological mechanisms underlying mood disorders in OSAHS patients remain poorly understood. This study aims to investigate the emotion processing mechanism in OSAHS patients with depressive mood using event-related potentials (ERPs).MethodsSeventy-four OSAHS patients were divided into the depressive mood and non-depressive mood groups according to their Self-rating Depression Scale (SDS) scores. Patients underwent overnight polysomnography and completed various cognitive and emotional questionnaires. The patients were shown facial images displaying positive, neutral, and negative emotions and tasked to identify the emotion category, while their visual evoked potential was simultaneously recorded.ResultsThe two groups did not differ significantly in age, BMI, and years of education, but showed significant differences in their slow wave sleep ratio (P = 0.039), ESS (P = 0.006), MMSE (P < 0.001), and MOCA scores (P = 0.043). No significant difference was found in accuracy and response time on emotional face recognition between the two groups. N170 latency in the depressive group was significantly longer than the non-depressive group (P = 0.014 and 0.007) at the bilateral parieto-occipital lobe, while no significant difference in N170 amplitude was found. No significant difference in P300 amplitude or latency between the two groups. Furthermore, N170 amplitude at PO7 was positively correlated with the arousal index and negatively with MOCA scores (both P < 0.01).ConclusionOSAHS patients with depressive mood exhibit increased N170 latency and impaired facial emotion recognition ability. Special attention towards the depressive mood among OSAHS patients is warranted for its implications for patient care.

Fractionated brain X-irradiation profoundly reduces hippocampal immature neuron numbers without affecting spontaneous behavior in mice

Whole brain radiotherapy (WBRT) is used to improve tumor control in patients with primary brain tumors, or brain metastasis from various primary tumors to improve tumor control. However, WBRT can lead to cognitive decline in patients. We assessed whether fractionated WBRT (fWBRT) affects spontaneous behavior of mice in automated home cages and cognition (spatial memory) using the Barnes maze.Male C57Bl/6j mice received bi-lateral fWBRT at a dosage of 4 Gy/day on 5 consecutive days. In line with previous reports, immunohistochemical analysis of doublecortin positive cells in the dentate gyrus showed a profound reduction in immature neurons 4 weeks after fWBRT. Surprisingly, spontaneous behavior as measured in automated home cages was not affected. Moreover, learning and memory measured with Barnes maze, was also not affected 4–6 weeks after fWBRT. At 10–11 weeks after fWBRT a significant difference in escape latency during the learning phase, but not in the probe test of the Barnes maze was observed.In conclusion, although we confirmed the serious adverse effect of fWBRT on neurogenesis 4 weeks after fWBRT, we did not find similar profound effects on spontaneous behavior in the automated home cage nor on learning abilities as measured by the Barnes maze. The relationship between the neurobiological effects of fWBRT and cognition seems more complex than often assumed and the choice of animal model, cognitive tasks, neurobiological parameters, and experimental set-up might be important factors in these types of experiments.