Significant Increase In Latency Research Articles

Postnatal Development of Synaptic Plasticity at Hippocampal CA1 Synapses: Correlation of Learning Performance with Pathway-Specific Plasticity.

To determine the critical timing for learning and the associated synaptic plasticity, we analyzed developmental changes in learning together with training-induced plasticity. Rats were subjected to an inhibitory avoidance (IA) task prior to weaning. While IA training did not alter latency at postnatal day (PN) 16, there was a significant increase in latency from PN 17, indicating a critical day for IA learning between PN 16 and 17. One hour after training, acute hippocampal slices were prepared for whole-cell patch clamp analysis following the retrieval test. In the presence of tetrodotoxin (0.5 µM), miniature excitatory postsynaptic currents (mEPSCs) and inhibitory postsynaptic currents (mIPSCs) were sequentially recorded from the same CA1 neuron. Although no changes in the amplitude of mEPSCs or mIPSCs were observed at PN 16 and 21, significant increases in both excitatory and inhibitory currents were observed at PN 23, suggesting a specific critical day for training-induced plasticity between PN 21 and 23. Training also increased the diversity of postsynaptic currents at PN 23 but not at PN 16 and 21, demonstrating a critical day for training-induced increase in the information entropy of CA1 neurons. Finally, we analyzed the plasticity at entorhinal cortex layer III (ECIII)-CA1 or CA3-CA1 synapses for each individual rat. At either ECIII-CA1 or CA3-CA1 synapses, a significant correlation between mean α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid/N-methyl-D-aspartic acid (AMPA/NMDA) ratio and learning outcomes emerged at PN 23 at both synapses, demonstrating a critical timing for the direct link between AMPA receptor-mediated synaptic plasticity and learning efficacy. Here, we identified multiple critical periods with respect to training-induced synaptic plasticity and delineated developmental trajectories of learning mechanisms at hippocampal CA1 synapses.

Hyperbaric Oxygen Therapy Attenuates the Whole Brain Radiotherapy-Induced Progressive Cognitive Dysfunction via Promoting Hippocampal Neurogenesis in Rats

Radiation therapy is a widely used brain tumor treatment; however, it can cause significant effects on the central nervous system, including neurogenesis impairment, microglia activation, and oxidative stress, leading to brain injury. Hyperbaric oxygen therapy (HBOT) has been shown to benefit various neurological conditions, but its effect on radiation-induced brain injury damage remains limited. This study aims to investigate the impact of HBOT on radiation-induced neurogenesis impairment, microglia activation, and lipid peroxidation levels, and also aim to assess the therapeutic potential of HBOT on preventing irradiation-induced brain injury. This study used a rat model that delivered different doses (2, 4, 10 Gy) of whole-brain radiation therapy (WBRT). The rats were divided into two groups: one received HBOT, and the other acted as the control (normal baric air, NBA) group. HBOT was performed on day 8 of post-radiation once per day for five consecutive days a week for four weeks. The rats were subjected to different irradiation dosages as described, followed by administration of 5-chloro-2'-deoxyuridine (CldU) immediately at day 0 or day 0 to day 7 and 5-iodo-2'-deoxyuridine (IdU) at day 2 or day 14 to day 28 following WBRT to detect serially replicating cells. Then the rats underwent behavioral tests to assess their cognitive and motor function every week. Brain tissues were collected and analyzed to evaluate neurogenesis, microglia activation, lipid peroxidation, and antioxidant levels using immunofluorescence stain and ELISA on days 7 and 28 of post-WBRT. The radial maze was used to measure spatial learning and memory in rats. Compared with the 0 Gy-WBRT group, the 2 Gy-, 4 Gy-, and 10 Gy-WBRT groups of rats displayed a significant increase in latency. Seven days of post-WBRT, the newly proliferation cells (IdU positive) and serial replicating cells (CldU+IdU double positive) in the hippocampal dentate gyrus were significantly increased but were coupled with apoptosis. The alterations in the cellular composition of the dentate gyrus area were observed on days 7 and 28 post-WBRT, including increased newborn neuroblast and neuron, but half underwent apoptosis, which is associated with microglia phagocytosis and results in cognitive impairment. The lipid peroxidation was significantly increased on day 28 of post-WBRT. HBOT improves cognitive function by attenuating the WBRT-induced lipid oxidation, newly-formed cell apoptosis, and microglia phagocytosis. Our present study suggests that HBOT may have a potential role in mitigating the effects of irradiation-induced brain injury by maintaining neurogenesis and reducing lipid peroxidation.

Effect of Ketamine and Dexmedetomidine as Adjuvant to Total Intravenous Anesthesia on Intraoperative Cranial Nerve Monitoring in the Patients Undergoing Posterior Fossa Craniotomies-A Randomized Quadruple Blind Placebo-Controlled Study.

Objectives Total intravenous anesthesia (TIVA) is used during surgery with intraoperative neurophysiological monitoring. Addition of adjuvant may minimize suppression of potentials by reducing doses of propofol. We studied the effect of addition of ketamine or dexmedetomidine to propofol-fentanyl-based TIVA on corticobulbar motor evoked potential (CoMEP) in patients undergoing posterior fossa surgeries. Materials and Methods Forty-two patients were assigned to three groups ( n = 14 each), Group S-saline, Group D-dexmedetomidine (0.25 μg/kg/h), and Group K-ketamine (0.25 mg/kg/h). Patients received propofol and fentanyl infusions along with study drugs. CoMEPs were recorded from muscles innervated by cranial nerves bilaterally at predefined intervals (T baseline , T 2 , T 3 , T 4 , and T 5 ). Effect on amplitude and latency of CoMEPs was assessed. Results A significant fall in CoMEP amplitude was observed across all analyzed muscles at time T 4 and T 5 in saline and dexmedetomidine group as compared with ketamine group, p -value less than 0.05. A significant increase in latency was observed at T4 and T5 among groups ( p -value, D vs. K = 0.239, D vs. S = 0.123, and K vs. S = 0.001). Conclusion Both ketamine and dexmedetomidine provide and allow effective recording of CoMEPs. Ketamine emerges as a better agent especially when prolonged surgical duration is expected as even propofol-fentanyl-based TIVA adversely affects CoMEPs when used for long duration.

P300 Wave Alterations and Cognitive Impairment in Cerebellum Lesions.

Patients with cognitive deficits have a prolonged latency and reduced amplitude of the P300 wave. However, no study has correlated P300 wave alterations with the cognitive performance of patients with cerebellar lesions. We aimed to determine if the cognitive status of these patients was associated with P300 wave alterations. We recruited 30 patients with cerebellar lesions from the wards of the N.R.S. Medical College, Kolkata, in West Bengal (India). The Kolkata Cognitive Screening Battery tasks and the Frontal Assessment Battery (FAB)were used to assess the cognitive status and the International Cooperative Ataxia Rating Scale (ICARS)for cerebellar signs. We compared the results with the normative data of the Indian population. Patients had P300 wave alterations with a significant increase in latency and a non-significant trend in amplitude. In a multivariate model, P300 wave latency was positively associated with the ICARS kinetic subscale (p = 0.005) and age (p = 0.009), regardless of sex and years of education. In the model that included cognitive variables, P300 wave latency was negatively associated with performance in phonemic fluency (p = 0.035) and construction (p = 0.009). Furthermore, P300 wave amplitude was positively associated with the FAB total score (p < 0.001). In closing,patients with cerebellar lesions had an increase in latency and a decrease in the amplitude of the P300 wave. These P300 wave alterations were also associated with worse cognitive performance and some of the subscales of theICARS, reinforcing that the cerebellum has motor, cognitive, and affective functions.

Clinical-immunological and neurophysiological correlations in paraneoplastic polyneuropathy caused by small cell lung cancer

Objective. To study the correlation between the neurological, immunological and neurophysiological signs of paraneoplastic polyneuropathy (PPNP) caused by small cell lung cancer (SCLC), to improve the quality of diagnosis of this pathology.Materials and methods. Clinical, immunological (anti-Hu) and neurophysiological (electromyography (EMG), electroneuromyography (ENMG), somatosensory evoked potentials (SSEP)) examination of 61 patients with PPNP caused by SCLC are presented.Results. It was established that sensory disorders in the limbs are the first and obligate clinical symptoms of PPNP, which precede the initial diagnosis of SCLC in 56% in 3-12 months, characterized by a predominance of a decrease in surface sensitivity in the form of distal hypoesthesia in 70% of cases. The motor form is characterized by an older age (67 years) than the sensory (60 years) and sensorimotor (58.0 years, p &lt;0,05). Motor disorders in the limbs occur in 46% of cases, manifested by mild symmetrical distal paresis of the legs and subclinical damage to the motor nerves of the upper extremities according to the results of ENMG (p &lt;0,001). Detection of anti-Hu in plasma is highly correlated with a significant increase in latency and a decrease in amplitudes component N22 in the conduct of SSEP, which indicates the defeat of the axons of the sensory nerves of the limbs (p &lt;0,05). Changes in amplitude parameters, with preserved speed indicators of nerves according to the results of ENMG indicate an axonal type of lesion (p &lt;0,05), which, in combination with the detection of anti-Hu in plasma, are pathognomonic signs of the paraneoplastic nature of the process.Conclusion. As a result of the study, clinical, immunological and neurophysiological features of various forms of PPNP were identified. The obtained correlations make it possible to diagnose the corresponding type of nerve pathology more accurately and in a timely manner and to suspect the development of oncological disease in time. The revealed changes in the indicators of the N22 component of SSEP can serve as a marker of axonal lesion of peripheral nerves, which with high diagnostic efficiency justifies the expediency of inclusion in the protocol of the ENMG study for verification of additional signs characteristic of PPNP.

Characteristics and dynamics of pathological changes in visual evoked potentials in multiple sclerosis

Clarification of the characteristics and dynamics of changes in the main indicators of visual evoked potentials (VEP) for a reverse chess pattern in patients with multiple sclerosis (MS) at various stages of the disease and severity of disability. The study of VEP was carried out on 477 subjects, 120 of which were healthy volunteers and 357 patients with MS, including those with clinically isolated syndrome (CIS; 22.7%), remitting course (RT; 55.7%), primary progressive course (PPT; 8.4%), secondary progressive course (VPT; 13.2%). Disability was assessed using the Expanded Disability Status Scale (EDSS). A high sensitivity of VEP in the detection of demyelinating damage to the visual pathways, including subclinical, was noted already at the initial stages of MS, which increases with the progression of the disease from 77.8 to 97.8%. There was a significant increase in latency (r=0.42, p<0.05) and a decrease in amplitude (r= -0.26, p<0.05) of the P100 peak as the EDSS score increased. In patients with MS, 5 patterns of VEP were identified depending on the level and severity of damage to the visual pathways, where pattern 1 is normative VEP, pattern 5 is the absence of VEP recording in case of a pronounced axonal-demyelinating lesion of the visual pathways (prechiasmal/postchiasmal levels). Patterns 1 and 2 are most typical for CIS (22.2 and 53.1%) or RT (20.1 and 26.6%). Patterns 3 and 4 are typical for APT (70 and 20%) and VPT (48.9 and 21.3%), pattern 5 - for VPT (19.1%). Patterns 3-5 predominated in patients with higher EDSS (r=0.54, p<0.05). The classification of VEP changes into patterns makes it possible to identify the dissemination of a focal lesion in the projections of the visual pathways, which increases the diagnostic efficiency of the study and makes it possible to assess the severity of MS.

SGLT-2 inhibitors as potential anticonvulsants: empagliflozin, but not dapagliflozin, renders a pronounced effect and potentiates the sodium valproate activity in pentylenetetrazole-induced seizures

On the way to the search for effective adjuvant medicines for epilepsy treatment, antidiabetic medicines such as sodium-glucose cotransporter-2 inhibitors, which are expressed not only in the kidneys but also in the brain, attract attention. From previous studies, it is known that dapagliflozin improves electroencephalographic parameters in rats on the model of pentylenetetrazole-induced seizures. However, the anticonvulsant potential of other medicines from this group needs to be clarified.&#x0D; The aim of the study is to estimate the effect of empagliflozin, dapagliflozin per se and their combinations with sodium valproate on pentylenetetrazole-induced seizures, as well as on muscle tone and motor coordination in mice.&#x0D; Material and methods. 42 random-bred male albino mice weighing 24-28 g were used in the experiments. Empagliflozin (20 mg/kg) and dapagliflozin (50 mg/kg) were administered intragastrically for 3 days. The classic anticonvulsant sodium valproate (150 mg/kg) per se, in combination with the medicines mentioned above, was administered in a similar regimen. On the second day, 30 minutes after administering all medicines, their effect on muscle tone and coordination of movements was determined in the rotarod test. On the third day, 30 minutes after the last administration of the medicines, their effect on pentylenetetrazole-induced (80 mg/kg subcutaneously) seizures was studied.&#x0D; Results. For the first time, a pronounced anticonvulsant effect of empagliflozin was established both when used alone (a significant increase in latency of the convulsions and a decrease in lethality by 43 %) and especially in combination with sodium valproate (a significant increase in latency of the convulsions, a decrease in the number and severity of seizures and a decrease in lethality by 83 %), as well as the absence of a muscle relaxant effect in both cases. Dapagliflozin has neither its anticonvulsant properties nor its effect on the action of sodium valproate. However, this medicine caused muscle relaxation, especially when combined with sodium valproate.&#x0D; Conclusions. The results suggest that empagliflozin, unlike dapagliflozin, has a high potential as an adjuvant medicine in treating epilepsy, as it enhances the efficacy of the classic anticonvulsant sodium valproate without muscle relaxant side effects

Protective Effects of N-Acetylcysteine on Dipentyl Phthalate Induced Cognitive Dysfunction and Brain Oxidative Stress in Mice

Background: Dipentyl phthalate (DPeP) is a plasticizer compound commonly used in polyvinylchloride plastic to enhance softness and flexibility. They are not bound covalently to plastic polymers; therefore, they can dissolve into the environment and adversely affect the health of humans and animals.&#x0D; Objectives: The aim of this study was to investigate the effect of DPeP on cognition and protective effects of N-acetylcysteine (NAC) on DPeP induced alteration in cognitive behaviour and oxidative stress markers in mice.&#x0D; Methods: Mice were orally treated with 2 doses (33 mg/kg and 100 mg/kg) of DPeP for 28 days. Cognitive functions were assessed using spatial navigation tasks on the Morris water maze and the step-down latency in the passive avoidance apparatus. Oxidative stress was assessed by examining the levels of malondialdehyde, glutathione, ferric reducing antioxidant power, and 8-hydroxy-deoxyguanosine levels in the whole brain of mice.&#x0D; Results: There was a significant increase in latency in spatial navigation tasks and a significant decline in the step-down latency in passive avoidance apparatus in the DPeP-treated group compared to the control groups. There was also a significant increase in the levels of oxidative stress following DPeP administration as seen with the rise in the levels of malondialdehyde, 8-hydroxy-deoxyguanosine, and a fall in glutathione and ferric reducing antioxidant power levels.&#x0D; Conclusion: The present study demonstrated that DPeP adversely affects learning and memory functions in mice by oxidative stress-mediated neuronal damage. These effects were attenuated by pretreatment with N-acetylcysteine.

ATTENUATION OF OXIDATIVE STRESS AND NEUROTOXICITY BY MK-801 (DIZOCILPINE) ON DIPENTYLPHTHALATE-INDUCED COGNITIVE DYSFUNCTION IN MICE

Objectives: The aim of our research is to study the effect of dipentylphthalate (DPeP), a plasticizer on cognition and various oxidative stress markers in mice, and to explore the modulatory effects of MK-801. Methods: In the present study, experimental mice were orally treated with two doses (33 and 100 mg/kg) of DPeP for 28 days. Cognitive functions were assessed using spatial navigation task on Morris water maze (MWM) and step-down latency (SDL) in passive avoidance apparatus. Oxidative stress was assessed by examining the levels of malondialdehyde (MDA), glutathione (GSH), ferric-reducing antioxidant power (FRAP), and 8-hydroxy-deoxyguanosine (8-OH-dG) levels in whole brain of mice. Results: DPeP exposure led to a statistically significant increase of latency in spatial navigation task and significant decline in the SDL in passive avoidance apparatus when compared to the control groups. Oxidative stress markers showed a significant increase following DPeP administration as seen with rise in levels of MDA, 8-OH-dG, and a fall in GSH and FRAP levels. Conclusion: The present data suggest that DPeP could adversely affect learning and memory functions in mice by an oxidative stress-mediated neuronal damage and pre-administration of MK-801 has the potential to attenuate these effects.

Effect of Tennis Expertise on Motion-in-Depth Perception at Different Speeds: An Event-Related Potential Study.

Tennis experts need to extract effective visual information from a sphere in high-speed motion, in which motion-in-depth perception plays an important role. The purpose of the current study was to investigate the impact of sphere speed and tennis expertise on motion-in-depth perception by using the expert–novice task paradigm along with event-related potential (ERP) technology. The study also explored differences in behavior and electroencephalogram (EEG) characteristics between tennis experts and novices. Results show that faster sphere movement led to shorter response times and a lower accuracy rate. The P1 component in the occipital–temporal region showed that the expert group activated earlier and were stronger when the sphere was far away. The latent period of P2 in the occipital region was significantly shorter in the expert group in comparison to the novice group. Faster speed led to the induction of increased P300 volatility and a significant increase in latency. The findings of the current study show that the speed of the sphere movement affects the invocation and allocation of cognitive resources in the process of motion-in-depth perception, irrespective of whether the athletes were experts or novices. There is a special effect in the process of motion-in-depth perception for experts, mainly because attention resources are invested earlier in experts rather than novices.

Effects of Satureja Bachtiarica Essential Oil in Preventing Seizure in Pentylenetetrazol-Kindled Mice.

Epilepsy is a group of chronic neurological disorders characterized by seizures. The present study aimed to investigate the effects of Satureja bachtiarica essential oil in preventing epilepsy. In this experimental study, 50 mice were randomly assigned to five groups of 10 each. The control group received normal saline plus tween-80 and after 30 min pentylenetetrazol (PTZ). Groups 2 and 3 were treated first with S. bachtiarica essential oil at 50 and 100 mg/kg, respectively and then after 30 min received PTZ. Group 4 received diazepam and 30 min later PTZ. Group 5 received flumazenil and 30 min later PTZ. After the last injection of PTZ, the time of seizure onset, seizure severity and score, the completion time of each seizure (attack episode), and mortality rate in different groups were recorded and compared. The administration of S. bachtiarica essential oil at 50 and 100 mg/kg to PTZ-treated mice caused a significant increase in latency to the first seizure and survival of mice, as well as a significant decrease in the frequency of the head and upper limbs seizure, total body seizures, tonic seizures, and jumping. S. bachtiarica essential oil at 100 mg/kg caused a significant decrease in the head tic frequency. The administration of flumazenil significantly inhibited S. bachtiarica essential oil-induced effects and increased the head and upper limbs seizures, tonic seizures, and jumping. The present study demonstrated that S. bachtiarica essential oil could prevent PTZ-induced seizure and these findings authenticate the traditional claims about the use of S. bachtiarica in treating epilepsy. The administration of S. bachtiarica essential oil at 50 and 100 mg/kg to pentylenetetrazol PTZ-treated mice caused a significant increase in latency to the first seizure.• The administration of S. bachtiarica essential oil at 50 and 100 mg/kg to PTZ-treated mice caused a significant decrease in the frequency of the head and upper limbs seizures, total body seizures, tonic seizures, and spin and jump.• The administration of flumazenil significantly inhibited S. bachtiarica essential oil-induced effects and increased the head and upper limbs seizures, tonic seizures, and jumping. Epilepsy is one of the most common disorders of the central nervous system, so that one in every 100 people is suffering from epilepsy globally. Despite the development of antiepileptic drugs, novel strategies are sought out because of drug resistance and the side effects resulting from these drugs at high concentrations. Researchers have focused on plants for certain reasons such as availability, the history of long-term use, being nature-based, and relative safety. In the current study, the effect of the pretreatment with S. bachtiarica essential oil in preventing seizure was studied in the pentylenetetrazol-kindled mice. The injection of 50 and 100 mg/kg of S. bachtiarica essential oil caused a significant increase in latency to the first seizure and survival duration, and a significant decrease in the frequency of the head and upper limbs seizures, tonic seizures, and spin and jump in the pentylenetetrazol-receiving mice.

Study of the latency of transcranial motor evoked potentials in spinal cord monitoring during surgery for adolescent idiopathic scoliosis

ObjectiveAn increase in the latency of a motor evoked potential might be as significant as a decrease in amplitude to predict a significant and clinically symptomatic neurological injury in spinal surgery for adolescent idiopathic scoliosis. The aim of the study was to investigate the impact of monitoring of latency of motor evoked potentials during spinal surgery for adolescent idiopathic scoliosis by describing intraoperative data. MethodsPreoperative recordings of 50 patients undergoing posterior spinal fusion for idiopathic scoliosis were studied. Latencies of appearance of the motor evoked potential curves on the right and left side were recorded for each group of muscles at several key moments during the procedure (basal, before the first implant, before and after corrective maneuvers). ResultsMean latencies were approximately the same in each muscle group on the right and the left side, before and after correction. There was no significant increase in latency during surgery. Overall results showed that the measured latency did not differ significantly between the two age groups (p=0.07). Negative correlation between height and the means of latencies was recorded in the abductor pollicis brevis and abductor digiti minimi (r=0.4; p=0.009), rectus femoris (r=0.4; p=0.01), tibialis anterior (r=0.4; p=0.007), and abductor hallucis (r=0.5; p=0.0004). No significant correlation was found between age and intraoperative parameters. ConclusionIntraoperative latency could be a reliable intraoperative monitoring criteria with low variability, that might be used to predict postoperative motor deficits in surgery for adolescent idiopathic scoliosis.

Monitoring Platform Evolution Toward Serverless Computing for 5G and Beyond Systems

Fifth generation (5G) and beyond systems require flexible and efficient monitoring platforms to guarantee optimal key performance indicators (KPIs) in various scenarios. Their applicability in Edge computing environments requires lightweight monitoring solutions. This work evaluates different candidate technologies to implement a monitoring platform for 5G and beyond systems in these environments. For monitoring data plane technologies, we evaluate different virtualization technologies, including bare metal servers, virtual machines, and orchestrated containers. We show that containers not only offer superior flexibility and deployment agility, but also allow obtaining better throughput and latency. In addition, we explore the suitability of the Function-as-a-Service (FaaS) serverless paradigm for deploying the functions used to manage the monitoring platform. This is motivated by the event oriented nature of those functions, designed to set up the monitoring infrastructure for newly created services. When the FaaS warm start mode is used, the platform gives users the perception of resources that are always available. When a cold start mode is used, containers running the application’s modules are automatically destroyed when the application is not in use. Our analysis compares both of them with the standard deployment of microservices. The experimental results show that the cold start mode produces a significant latency increase, along with potential instabilities. For this reason, its usage is not recommended despite the potential savings of computing resources. Conversely, when the warm start mode is used for executing configuration tasks of monitoring infrastructure, it can provide similar execution times to a microservice-based deployment. In addition, the FaaS approach significantly simplifies the code logic in comparison with microservices, reducing lines of code to less than 38%, thus reducing development time. Thus, FaaS in warm start mode represents the best candidate technology to implements such management functions.

Влияние гипотермии на импульсную активность нейронов первичной слуховой коры домовой мыши (Mus musculus)

The paper reports the results of the study that investigated discharges of neurons in the primary auditory cortex of the house mouse (Mus musculus) under general hypothermia. The study focused on multiunit response amplitude, latencies and post-stimulus adaptation to a series of tones at normal body temperature, at body temperature reduced by 1–6 ºС and after the normalization of temperature in anesthetized animals. The data were obtained from extracellular recordings. The study showed a significant increase in latencies (on average of 49 ms) and the replacement of patch discharge with a long-latency response. Anesthetized animals do not show such behaviour of auditory cortex neurons at normal body temperature. The amplitude of multiunit responses decreased to the point of a complete fade-away. Parameters of post-stimulus adaptation to a series of tonal signals registered under normal body temperature were distorted during hypothermia. Normalization of body temperature resulted in the recovery of activity typical for primary auditory cortex neurons: the appearance of responses to sound signals with a latency of less than 35 ms, the normalization of post-stimulus adaptation in response to a series of tonal signals in all studied neurons and the normalization of summary response amplitude.

NEUROPHYSIOLOGICAL EFFECT OF LOW LEVEL LASER THERAPY ON ULNAR NERVE

Low level laser therapy is widely used in managing pain and inflammation in musculoskeletal ailments. Its effect on Peripheral nervous system and its function is not yet clearly studied. Objective: To analyze the neurophysiological effect of Low level laser irradiation on ulnar nerve MATERIALS AND METHODS: Sixty healthy subjects with age group between 20-30 years of both genders were recruited in this experimental study design.. The procedure was clearly explained to the subjects and informed consent was obtained. They were assigned randomly to either Ga. As.Laser group or Sham laser group. All the subject’s were positioned in supine lying with the irradiated dominant hand kept at 135 degrees of flexion. Ground electrode was placed over the thenar eminence. The subject's skin (electrode placement area) was degreased for proper transmission of laser. Nerve conduction velocity was recorded Antidromically. A 904nm diode laser was used to irradiate the skin overlying the ulnar nerve behind the medial epicondyle of the humerus for 20 secs. The laser was set to deliver continuous energy at 4.0 J/cm².Antidromically action potential, peak to peak amplitude, onset latency, nerve conduction velocity was recorded before and after irradiation of the ulnar nerve. RESULT: The study revealed that there was a significant difference in onset Latency (P=0.0021) but there was no significant difference in Nerve conduction velocity (P=0.2738) and PPA (P=1.0000) between laser group and sham laser group. CONCLUSIONS: Low level laser irradiation of skin overlying the ulnar nerve resulted in a significant increase in latency in this study. This increase in latency corresponds to a decrease in sensory nerve conduction velocity and could help explain the alleged pain relieving effects of low level laser irradiation.

Response to sertraline and antiepileptic drugs in pentylenetetrazole kindling in rats

Anti-epileptic drugs (AEDs) are the mainstay of epilepsy treatment but these may be a potential risk factor for behavioral disturbances particularly depression which requires treatment. In this study, the effect of antidepressant sertraline (SRT) in combination with AEDs sodium valproate (SV) and levetiracetam (LEV) on seizures, cognitive impairment and oxidative stress in rats was evaluated.After administration of 24th injection of pentylenetetrazole (PTZ), 77.8% rats were kindled. Administration of SRT showed no protective effect on kindling development while SV was 100% protective. With LEV 42.9% were kindled. On combining SRT with SV or LEV 25% and 20% rats were kindled. A significant increase in latency to reach platform zone in Morris water maze(MWM), and increased transfer latencies in Elevated plus maze(EPM) was observed in PTZ kindled rats as compared to normal control on day 49 and when LEV was combined with SRT. In EPM test, however none of the drug treatments had any effect on transfer latencies except LEV pretreated kindled group. In Passive avoidance (PA) test, kindling was associated with a significant decrease in retention time(p = 0.018) while LEV and SV had no effect. The PTZ kindled rats showed significantly higher malondialdehyde(MDA) levels in brain hippocampus(p = 0.0286) while both SRT and SV were associated with significantly lower MDA levels as compared to kindled control group. In case of glutathione (GSH), kindling had no significant effect.The use of sertraline for depression in persons with epilepsy on AEDs needs to be carefully evaluated and monitored due to likelihood of individual variation.

Brainstem Evoked Auditory Responses in Neonatal Hyperbilirubinemia Infants

Jaundice is a common finding in neonates affecting 70% of term and 80% of preterm neonates during the first week of life. Objective of this study is to evaluate auditory and brainstem responses in hyperbilirubinemia infants and to see if there is any statistically significant increase in latencies of wave I and V waves with rise in bilirubin levels. In the present study we have taken 53 infants with hyperbilirubinemia&gt;11mg% &amp; with no other risk factors like preterm, low birth weight, birth asphyxia and age and sex matched controls who visited pediatric OPD of Bapuji Child Health Centre were evaluated using RMS EMG. EP MARK –II machine. Latencies of Waves I and V and inter-peak latency of I-V were recorded. Latency of wave V and IPL I-V were increased slightly compared to normal control subjects. Increase in the threshold leading to hearing impairment in the affected infants and complete deafness where none of the waves were recorded signify that hyperbilirubinemia is a risk factor for deafness. Since hyperbilirubinemia is a risk factor for hearing impairment, their hearing screening by BERA at the earliest and follow up will help in their earliest initiation of rehabilitation when the brain is sensitive to the development of speech &amp; language.

Electrophysiological biomarkers of central nervous system affection in cases of chronic obstructive pulmonary disease (COPD)

BackgroundChronic obstructive pulmonary disease is associated with significant systemic abnormalities which includes systemic inflammation and neurohormonal activation that are considered the main mechanisms of the pathophysiology in systemic involvement. The aim of the present study was to detect the subclinical affection of the central nervous system in patients with stable chronic obstructive pulmonary disease.ResultsForty patients with chronic obstructive pulmonary disease were enrolled in this study and 30 healthy subjects as a control group. All patients and healthy subjects were submitted to full history taking, clinical examination, arterial blood gases, spirometry, evoked potential, and electroencephalogram. Regarding to brain stem auditory evoked potentials, there was a statistically significant increase of latency of waves numbers I, III, and V, and a statistically significant increase of interpeak latencies I–III in the COPD group when compared to the control group. On the other hand, there was a statistically significant decrease of brain stem auditory evoked potential I and V amplitudes on both sides in the COPD group when compared to the control group. In visual evoked potential, there was a statistically significant increase of latency and decrease of amplitude of P100. In addition, there was a statistically significant increase of electroencephalogram changes in the COPD group when compared to the control group (20.0% vs. 3.3%, respectively).ConclusionIn patients with chronic obstructive pulmonary disease, the central nervous system could be affected subclinically as the severity of chronic obstructive pulmonary disease increased, and the patient should be electrophysiologically monitored for early detection of nervous system affection.

Fyn-tau Ablation Modifies PTZ-Induced Seizures and Post-seizure Hallmarks of Early Epileptogenesis.

Both Fyn and tau have been associated with neuronal hyperexcitability and neurotoxicity in many tauopathies, including Alzheimer's disease (AD). Individual genetic ablation of fyn or tau appears to be protective against aberrant excitatory neuronal activities in AD and epilepsy models. It is, however, still unknown whether ablation of both Fyn and tau can likely elicit more profound anti-seizure and neuroprotective effects. Here, we show the effects of genetic deletion of Fyn and/or tau on seizure severity in response to pentylenetetrazole (PTZ)-induced seizure in mouse models and neurobiological changes 24 h post-seizures. We used Fyn KO (fyn−/−), tau KO (tau−/−), double knockout (DKO) (fyn−/−/tau−/−), and wild-type (WT) mice of the same genetic background. Both tau KO and DKO showed a significant increase in latency to convulsive seizures and significantly decreased the severity of seizures post-PTZ. Although Fyn KO did not differ significantly from WT, in response to PTZ, Fyn KO still had 36 ± 8% seizure reduction and a 30% increase in seizure latency compared to WT. Surprisingly, in contrast to WT, Fyn KO mice showed higher mortality in <20 min of seizure induction; these mice had severe hydrocephalous. None of the tau−/− and DKO died during the study. In response to PTZ, all KO groups showed a significant reduction in neurodegeneration and gliosis, in contrast to WT, which showed increased neurodegeneration [especially, parvalbumin (PV)-GABAergic interneurons] and gliosis. DKO mice had the most reduced gliosis. Immunohistochemically, phospho-tau (AT8, pS199/S202), Fyn expression, as well as Fyn-tau interaction as measured by PLA increased in WT post-PTZ. Moreover, hippocampal Western blots revealed increased levels of AT8, tyrosine phospho-tau (pY18), and phosphorylated Src tyrosine family kinases (pSFK) in PTZ-treated WT, but not in KO, compared to respective controls. Furthermore, PV interneurons were protected from PTZ-induced seizure effects in all KO mice. The levels of inwardly rectifying potassium (Kir 4.1) channels were also downregulated in astrocytes in the WT post-PTZ, while its levels did not change in KO groups. Overall, our results demonstrated the role of Fyn and tau in seizures and their impact on the mediators of early epileptogenesis in PTZ model.

Liquid Crystalline Nanoparticles for Nasal Delivery of Rosuvastatin: Implications on Therapeutic Efficacy in Management of Epilepsy.

In the present study we investigated the protective role of intranasal rosuvastatin liquid crystalline nanoparticles (Ros-LCNPs) against pentylenetetrazole (PTZ) induced seizures, increasing current electroshock (ICES) induced seizures, and PTZ-induced status epilepticus. From the dose titration study, it was evident that intranasal rosuvastatin (ROS), at lower dose, was more effective than oral and intraperitoneal ROS. The Ros-LCNPs equivalent to 5 mg/kg ROS were developed by hydrotrope method using glyceryl monooleate (GMO) as lipid phase. The high resolution TEM revealed that the formed Ros-LCNPs were cubic shaped and multivesicular with mean size of 219.15 ± 8.14 nm. The Ros-LCNPs showed entrapment efficiency of 70.30 ± 1.84% and release was found to be biphasic following Korsmeyer–Peppas kinetics. Intranasal Ros-LCNPs (5 mg/kg) showed significant increase in latency to PTZ-induced seizures and ICES seizure threshold compared to control and intranasal ROS solution. Additionally, intranasal Ros-LCNPs provided effective protection against PTZ-induced status epilepticus. No impairment in cognitive functions was observed following intranasal Ros-LCNPs. The results suggested that Ros-LCNPs could be an effective and promising therapeutics for the epilepsy management.