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Hydroxychloroquine for treatment of rheumatoid arthritis: multifocal electroretinogram and laser flare-cell photometry study

PurposeTo evaluate early changes in multifocal electroretinogram (mfERG) and subclinical aqueous humor flare and cellularity in patients receiving hydroxychloroquine (HCQ) as treatment for rheumatoid arthritis.MethodsTen patients receiving treatment with HCQ and no ophthalmic symptoms were enrolled. After complete ocular examination, mfERG and laser flare-cell photometry were performed. Patients were also divided into two subgroups with HCQ cumulative dose (CD) higher or lower than 500 g. Results obtained were compared with a control group of ten healthy subjects and statistical analysis was performed.ResultsIn patients receiving HCQ treatment, mfERG P1-wave in ring 2 showed a significant reduction in amplitude and a significant increase in latency compared to healthy control subjects, respectively resulting in 1.143 μV vs 1.316 μV (P=0.040) and 38.611 ms vs 36.334 ms (P=0.024). These changes are highly related to CD. Furthermore, when using the laser flare-cell photometry, a significant increase in aqueous humor flare and cellularity was shown in patients with CD higher than 500 g, resulting in a mean value of 14.4 ph/ms compared to 8.1 ph/ms in patients with CD lower than 500 g (P=0.0029). These reports appear highly related to CD (P=0.001). Receiver operating characteristic curve analysis showed mfERG P1-wave amplitude in ring 2 as the most sensitive value in detecting early HCQ-related retinopathy.ConclusionMfERG was shown to be a very sensitive test in detecting early retinal toxicity and should be used for the screening of patients receiving HCQ treatment. Although less sensitive, laser flare-cell photometry can provide further information to evaluate early toxic retinal cell damage.

Влияние острой гипоксии в позднем пренатальном периоде на проявление нейротоксического эффекта толуола у взрослых белых крыс

The aim of the present investigation is to estimate the role of prenatal hypoxia in toluene neurotoxic effect in adult rats. Toluene-induced behavioral and electroencephalographic manifestations were investigated in animals with normal and abnormal embryonic development. To simulate prenatal hypoxia, we gave subcutaneous injections of sodium nitrite to pregnant female rats in a dose of 50mg/kg on the 18–19th day of gestation. At the age of 3months the males from the offspring were exposed to toluene inhalation (560mg/m3, 4w eeks, 4h/day, 5days/week). After toluene inhalation exposure we estimated rats’ individual behavior by plus maze test and visual and auditory evoked potentials (VEPs and AEPs). Toluene reduced P2N2 interpeak amplitude of VEPs compared with control rats without any latency change. We found out that toluene exposure of rats with acute prenatal hypoxia in late gestation had led to inhibition of motor activity and a statistically significant increase in latency of VEP’s N1, AEP’s P3 and N1P2 interpeak amplitude of AEP in comparison with all remained groups. Thus, these results show that prenatal hypoxic damage to the central nervous system is an aggravating factor in toluene intoxication in rats.

Early hydroxychloroquine retinal toxicity enhanced by multifocal electroretinogram and laser flare‐cell meter

PurposeThe aim of this study is the evaluation of the multifocal electroretinogram (mfERG) and the laser flare‐cell meter methodology (LFM) in early detection of hydroxychloroquine (HCQ) retinal toxicity.MethodsWe enrolled 10 patients mean age 64.8 years with rheumatoid arthritis in therapy with hydroxychloroquine (400 mg/day) and cumulative dose (CD) of 625.6 ± 167.44‐g with no signs of retinal toxicity. As control group we recruited 10 health subjects mean age 61.3 years. MfERG (Retimax Plus, CSO, Florence, Italy) and LFM (FM‐500, Kowa, Tokio, Japan) were performed in all patients and controls. The Wilcoxon signed‐rank test and Spearman's correlation test was performed considering p < 0.05 as positive.ResultsPatients treated with HCQ showed compared to controls a significant amplitude reduction 0.518 ± 0.348 μV vs. 0.745 ± 0.337 μV (p = 0.035) with equally significant increase in latency 38.611 ± 2.857 ms vs. 36.334 ± 2.212 ms (p = 0.024) P1 wave in ring 2 of mfERG. The alteration of dependent values of mfERG correlated to the HCQ‐CD. To evaluate the behavior of the flare we divided the patients into two groups according to the CD: a group with CD > 500‐g and one with CD < 500‐g. The CD Group > 500‐g had a significant increase in flare values than the CD group < 500‐g: 14.4 ± 6.266 pg/ms vs. 8.1 ± 2.828 pg/ms (p = 0.008). The increase in the flare on the CD group>500 g was found to be related to the drug CD (r = 0.899; p = 0.001).ConclusionsWe found that mfERG P1 wave implicit time in ring 2 and the flare is the more sensitive test for demonstrating retinal dysfunction from HCQ toxicity in the setting of a normal fundus with a normal authomated visual field 10.2 and normal visual acuity. The increase in the flare would indicate not only a damage to the iris and cliary body pigmented cells but also an enzyme‐based breakdown of the blood retinal barrier directly caused by HCQ.

Anticonvulsant mechanism of saponins fraction from adventitious roots of Ficus religiosa: possible modulation of GABAergic, calcium and sodium channel functions

In our previous studies, quantified saponins-rich fraction from adventitious root extract of Ficus religiosa L., Moraceae, showed anticonvulsant effect in acute, as well as chronic mice models of epilepsy. The present study was designed to reveal putative anticonvulsant mechanism of quantified saponins-rich fraction using target specific animal models. The anticonvulsant effect of quantified saponins-rich fraction was initially studied in maximal electroshock and pentylenetetrazol test at 1, 2 and 4mg/kg; i.p. doses. Based on the results of initial anticonvulsant testing, different groups of mice were injected with vehicle or quantified saponins-rich fraction (4mg/kg; i.p.), 30min prior to an injection of N-methyl-d-aspartic acid (100mg/kg; s.c.), bicuculline (5mg/kg; i.p.), strychnine hydrochloride (2mg/kg; i.p.), BAY k-8644 (37.5μg; i.c.v.), veratridine (500μg/kg; i.p.) and the convulsive episodes were studied. Treatment with the extract (1, 2 and 4mg/kg) showed significant protection in maximal electroshock and pentylenetetrazol-induced convulsion tests, in a dose-dependent manner. Moreover, quantified saponins-rich fraction at 4mg/kg dose showed significant increase in latency to clonic convulsions, decrease in seizure severity and increase in average wave amplitude in bicuculline, BAY k-8644 and veratridine tests, respectively, as compared to vehicle control. However, SRF treatment failed to abolish N-methyl-d-aspartic acid and strychnine-induced convulsions, indicated by insignificant change in the appearance of turning behavior and onset of tonic extension, respectively, as compared to vehicle control. From the results of present study, it is concluded that quantified saponins-rich fraction suppress maximal electroshock, pentylenetetrazol, bicuculline, BAY k-8644 and veratridine-induced convulsions, indicating its GABAergic, Na+ and Ca2+ channel modulatory effects. Further it can be correlated that quantified saponins-rich fraction causes deactivation of voltage-gated Na+ and Ca2+ channels, without effecting ligand-gated Na+ and Ca2+ channels. More studies are required at molecular levels using in vitro techniques to understand the exact molecular interactions of quantified saponins-rich fraction with these pathways.

Analgesic synergism of gabapentin and carbamazepine in rat model of diabetic neuropathic pain

Purpose: To evaluate synergy in the analgesic effects of a combination therapy of carbamazepine (CBZ) and gabapentin (GBP) in diabetic neuropathic pain.Methods: Neuropathic pain was produced in rats by a single intraperitoneal injection of streptozotocin (STZ) at 60 mg/kg. CBZ, GBP, and their combination were orally administered at varying doses (GBP 30 - 180 mg/kg; CBZ 20 - 40 mg/kg) comparable to their therapeutic doses in humans. Nociceptive responses in the diabetic rats were assessed using hot plate test.Results: Hot plate latency significantly increased with oral administration of GBP at a dose of 180 mg/kg when compared with control group (p < 0.05), while at a dose of 90 mg/kg, the increase was not significant. Oral administration of CBZ at doses of 20 and 40 mg/kg did not produce any significant impact on hot plate latency. However, a combination of GBP at 90 mg/kg and CBZ at 20 mg/kg produced significant increase in latency, compared with control group and other groups (p < 0.05), except the group that received 180 mg/kg GBP. The combination of low dose GBP 30 mg/kg and carbamazepine 30 mg/kg had no significant effect on latency (p > 0.05).Conclusion: The results obtained in this study provide useful information on the combination therapy of GBP and CBZ, which may be applied in the treatment of pain in diabetic neuropathy.Keywords: Diabetic neuropathy, Carbamazepine, Gabapentin, Hot-plate test

Peripheral and Central Nervous System Involvement in Recently Diagnosed Cases of Hypothyroidism: An Electrophysiological Study.

Background:Hypothyroidism, one of the most common endocrine disorders, may induce neurological abnormalities at an early stage of the disease.Aim:The study was designed to assess the electrophysiological alterations of some selected variables of nerve conduction, brainstem auditory evoked potentials (BAEPs), and visual evoked potentials (VEPs) in hypothyroid patients.Subjects and Methods:Sixty patients of newly diagnosed hypothyroidism and an equal number of age-matched controls were selected for the study. Nerve conduction studies that included parameters as latencies, conduction velocities, and amplitude of motor nerves, i.e., median, ulnar, common peroneal, tibial nerve, and sensory nerves, i.e., median and sural nerves was performed in both hypothyroid patients and controls. Further, BAEPs and VEPs of all the patients were done. The data were compiled and statistically analyzed using Student's unpaired t-test to observe any electrophysiological alterations in hypothyroid patients as compared to healthy controls.Results:On comparative evaluation, statistically significant increase in latency of median, ulnar, tibial, and sural nerves; decrease in conduction velocities of all the tested nerves and decrease in amplitude of median, tibial, and sural nerves was observed in hypothyroid patients. Statistically significant increase in latencies, interpeak latencies, and decrease in amplitudes of BAEP waves and statistically significant increase in P100 latency of VEP was seen in hypothyroid patients.Conclusion:The results of our study suggest that peripheral and central neuropathy develops in patients of hypothyroidism at an early stage of disease and the electrophysiological investigations of such patients can help in timely detection and treatment of neurological disorders that occur due to thyroid hormone deficiency.

Phytochemical Screening and Antinociceptive and Antidiarrheal Activities of Hydromethanol and Petroleum Benzene Extract of Microcos paniculata Barks.

Introduction. Microcos paniculata is traditionally used for treating diarrhea, wounds, cold, fever, hepatitis, dyspepsia, and heat stroke. Objective. To investigate the qualitative phytochemical constituents of hydromethanol (HMPB) and petroleum benzene extract of Microcos paniculata barks (PBMPB) and to evaluate their antinociceptive and antidiarrheal activities. Methods. Phytochemical constituents and antinociceptive and antidiarrheal activities were determined and evaluated by different tests such as Molisch's, Fehling's, Mayer's, Wagner's, Dragendorff's, frothing, FeCl3, alkali, Pew's, and Salkowski's test, general test of glycosides, Baljet and NH4OH test, formalin-induced paw licking, acetic acid-induced writhing, tail immersion, and hot plate tests, and castor oil and MgSO4 induced diarrheal tests. Results. These extracts revealed the presence of saponins, flavonoids, and triterpenoids and significantly (⁎ P < 0.05, versus control) reduced paw licking and abdominal writhing of mice. At 30 min after their administration, PBMPB revealed significant increase in latency (⁎ P < 0.05, versus control) in tail immersion test. In hot plate test, HMPB and PBMPB 200 mg/kg showed significant increase in response latency (⁎ P < 0.05, versus control) at 30 min after their administration. Moreover, both extracts significantly (⁎ P < 0.05, versus control) inhibited percentage of diarrhea in antidiarrheal models. Conclusion. Study results indicate that M. paniculata may provide a source of plant compounds with antinociceptive and antidiarrheal activities.

Assessment of a carbon dioxide laser for the measurement of thermal nociceptive thresholds following intramuscular administration of analgesic drugs in pain-free female cats

ObjectiveTo assess the potential of a thermal carbon dioxide (CO2) laser to explore antinociception in pain-free cats. Study designExperimental, prospective, blinded, randomized study. AnimalsSixty healthy adult female cats with a (mean ± standard deviation) weight of 3.3 ± 0.6 kg. MethodsCats were systematically allocated to one of six treatments: saline 0.2 mL per cat; morphine 0.5 mg kg−1; buprenorphine 20 μg kg−1; medetomidine 2 μg kg−1; tramadol 2 mg kg−1, and ketoprofen 2 mg kg−1. Latency to respond to thermal stimulation was assessed at baseline and at intervals of 15–30, 30–45, 45–60, 60–75, 90–105 and 120–135 minutes. Thermal thresholds were assessed using time to respond behaviourally to stimulation with a 500 mW CO2 laser. Within-treatment differences in response latency were assessed using Friedman’s test. Differences amongst treatments were assessed using independent Kruskal–Wallis tests. Where significant effects were identified, pairwise comparisons were conducted to elucidate the direction of the effect. ResultsCats treated with morphine (X2 = 12.90, df = 6, p = 0.045) and tramadol (X2 = 20.28, df = 6, p = 0.002) showed significant increases in latency to respond. However, subsequent pairwise comparisons indicated that differences in latencies at specific time-points were significant (p < 0.05) only for tramadol at 60–75 and 90–105 minutes after administration (21.9 and 43.6 seconds, respectively) in comparison with baseline (11.0 seconds). No significant pairwise comparisons were found within the morphine treatment. Injections of saline, ketoprofen, medetomidine or buprenorphine showed no significant effect on latency to respond. Conclusions and clinical relevanceThe CO2 laser technique may have utility in the assessment of thermal nociceptive thresholds in pain-free cats after analgesic administration and may provide a simpler alternative to existing systems. Further exploration is required to examine its sensitivity and comparative utility.

Visual evoked potential changes in diabetes mellitus

Background: Diabetes Mellitus (DM) a metabolic disorder is the most common cause of neuropathy. Electrophysiological studies are commonly employed to detect the neuropathy. The present study was undertaken to find out the utility of visual evoked potential (VEP) as an early indicator of central neuropathy in diabetic patients. Materials & methods: The present study was carried out in 60 healthy subjects and 60 diagnosed DM patients of age group 20 to 40 years. Visual evoked potential (VEP) tests were recorded in sports physiology laboratory of Medical College on an outpatient basis, using RMS EMG.EP machine. It is to find out whether the VEP latencies are altered in diabetes or not. Result: In our study there is statistically significant increase in latencies of P100 waves of both eyes in diabetic patients as compared to control subjects (p 0.05). Conclusion: The abnormalities in the VEP response occur in diabetic patients before the development of overt retinopathy. So, VEP measurements can be used for the early diagnosis of central neuropathy to offer an early opportunity for proper management.

Tat-induced histopathological alterations mediate hippocampus-associated behavioural impairments in rats.

BackgroundHIV-1 is a global catastrophe, and is exceedingly prevalent in Sub-Saharan Africa. HIV-associated neurocognitive disorder is characterized by symptoms such as motor impairments, a decline in cognition, and behavioural irregularities. The aim of this study was to provide insight into the fundamental behavioural and histopathological mechanisms underlying the development and progression of HIV-1 neuropathology.MethodsUsing stereotaxic techniques, Tat protein Clade B (1 μg/μl, 10 μl) was injected bilaterally into the dorsal hippocampus of male Sprague–Dawley rats. The Morris water maze (MWM) and novel object recognition test (NORT) were used to assess spatial learning and recognition memory, respectively. Haematoxylin and eosin staining was used to identify the histopathological changes.ResultsA highly significant increase in latency to reach the hidden platform in the MWM implied that noteworthy hippocampal damage had occurred. Severe behavioural deficits were also observed in the NORT where the Tat-injected group showed a greater preference for a familiar object over a novel one. This damage was confirmed by the histopathological changes (increased astrogliosis, cells becoming eosinophilic and a significant reduction in the pyramidal cell layer) observed in the hippocampus. Additionally, increases in the hippocampal mass and protein were observed, consistent with the structural alterations.ConclusionThis study highlights the relationship between hippocampal-associated behavioural changes and histologic alterations following stereotaxic intra-hippocampal administration of Tat protein in rats. The implications of this study may positively impact the fields of immunology and neuroscience by encouraging future researchers to consider novel strategies to understand the complexities of the pathogenesis of HIV-associated neurocognitive disorder.

Evaluation of Analgesic and Anti-Inflammatory Activity of Extract of Holoptelea Integrifolia and Argyreia Speciosa in Animal Models

Long term use of NSAIDs, opioids and corticosteroids was associated with serious adverse effects. Hence, the search for a safer analgesic and anti-inflammatory agent was always going on. It was considered worthwhile to evaluate analgesic and anti-inflammatory activities of Holoptelea integrifolia and Argyreia speciosa. To evaluate analgesic and anti-inflammatory activities of aqueous extract of leaves of Holoptelea Integrifolia and methanolic extract of Argyreia Speciosa root powder in mice and rats. After obtaining permission from animal ethics committee, the animals were divided into 7 groups of 6 animals each {control, standard - ibuprofen 100mg/kg, Holoptelea integrifolia (250 and 500 mg/kg), Argyreia speciosa (100 and 300 mg/kg) and combination of Holoptelea integrifolia (250 mg/kg) and Argyreia speciosa (100 mg/kg)}. The analgesic activity of the extracts was evaluated using tail-flick with radiant heat and acetic acid induced writhing method and the anti-inflammatory activity was evaluated using carrageenan induced paw oedema method. One-way ANOVA followed by post-hoc test. p < 0.05 was considered to be significant. In tail-flick method, both Holoptelea integrifolia and Argyreia speciosa produced significant (p<0.05) increase in latency as compared to control, their combination showed a significant increase in latency as compared to control as well as to the standard - ibuprofen. In writhing method, Holoptelea integrifolia and Argyreia speciosa, alone and in combination, significantly decreased the number of writhes as compared to control. In paw oedema method, both Holoptelea integrifolia and Argyreia speciosa showed significant inhibition of paw oedema as compared to control and the activity was comparable to ibuprofen. Extracts of Holoptelea integrifolia and Argyreia speciosa exhibits significant central and peripheral analgesic and anti-inflammatory activity.

Visual evoked potentials in examining the visual analyzer in patients with multiple sclerosis

Objective: to study the neurophysiological features of the visual analyzer in patients with multiple sclerosis (MS) to optimize the early diagnosis of the disease. Patients and methods. Seventy-nine patients (57 women and 22 men, mean age 34.31±4.7 years) diagnosed as having MS were examined. The mean duration of the disease with consideration for its clinical form was 3.3±2.2 years in relapsing-remitting MS (RRMS), 9.1±4.2 years in secondary progressive MS (SPMS), and 2.7±1.9 years in primary progressive MS (PPMS). Results and discussion. The neurophysiological examination indicated that demyelination processes in MS proceeded differently in response to dissimilar lights in the structures of the visual analyzer. The most marked significant (p<0.01) deviations in the values of visual evoked potentials (VEPs) to the black-white tessellated pattern (TP) were observed in the patients with SPMS and in those with PPMS. The latency of the P100 wave increased dramatically and differed significantly (p<0.001) from those in the control group (127.09 msec for RRMS, 128.3 msec for SPMS, 124.5 msec for PPMS, and 106.1 msec in the control). Amplitude analysis could reveal a significant decrease in the force of a N75–N100 wave response to the black-white stimulus in all the clinical groups, averaging 3.3 μW (8.5 μW in the control). The latency of the P100 wave to the red-yellow TP increased considerably and differed significantly (p<0.001) from that in the control group, by comprising 147.29±1.19 msec for RRMS, 150.23±1.49 msec for SPMS, and 144.38±2.11 msec for PPMS. There were the same changes that to the greenblack TP. Examination of 25 patients with MS established higher levels of IgG antibodies against myelin basic protein. The most significant latency increase occurs in response to the color spectrum of visible light against the black-white background, which may serve as an early diagnostic criterion for MS. These changes lead to a sharp decrease in a cortical feedback. The use of the color pattern will largely contribute to the improved early diagnosis of MS.

Efficient and Reliable Application Layer Multicast for Flash Dissemination

To disseminate messages from a single source to a large number of targeted receivers, a natural approach is the tree-based application layer multicast (ALM). In time-constrained flash dissemination scenarios, e.g. earthquake early warning, where time is of the essence, the reliable extensions of the tree-based ALM using ack-based failure recovery protocols cannot support reliable dissemination in the timeframe needed. In this paper, we propose FaReCast which exploits path diversity, i.e., exploit the use of multiple data paths, to achieve fast and reliable data dissemination. First, we design a forest-based M2M (Multiple parents-To-Multiple children) ALM structure where every node has multiple children and multiple parents. The intuition is to enable lower dissemination latency through multiple children, while enabling higher reliability through multiple parents. In order to maintain the M2M ALM structure in a scalable and reliable manner, we develop a DHT-based Distributed Configuration Manager. Second, we design multidirectional multicasting algorithms that effectively utilize the multiple data paths in the M2M ALM structure. A key aspect of our reliable dissemination mechanism is that nodes, in addition to communicating the data to children, also selectively disseminate the data to parents and siblings. As compared to trees using traditional multicasting algorithm, we observe an 80 percent improvement in reliability under 20 percent of failed nodes with no significant increase in latency for over 99 percent of the nodes. Moreover, we notice that FaReCast can reduce the network overhead more than 50 percent by tuning the M2M structure, as compared to the other reliable ALM based disseminations.

EHMTI-0181. Fast recovery of visual evoked potential amplitude after photostress in migraine patients between attacks

Results VEP parameters did not differed between groups at the baseline. In all groups, the VEPs recorded after PS showed a significant increase in latency at 20s. In HV, N75-P100 amplitude significantly decreased 20s after PS, and recovered subsequently. There was no effect in the migraine groups. In fact, the percentage reduction in N75-P100 amplitude observed at 20s after photostress in MO and MA patients were lower than in HV (MO & MA vs. HV P<0.05). When data of migraine patients were combined, the percentage of amplitude change at 20s was negatively correlated with number of days since the last migraine attack (r=-0.525, p=0.02).

English

OBJECTIVE: Jaundice is a common finding in neonates affecting 70% of term and 80% of preterm neonates during the first week of life. So the objective of this study is to evaluate auditory and brainstem responses in hyper bilirubinemic infants and to see if there is any statistically significant increase in latencies of wave I and V waves. To initiate rehabilitative procedure as early in life as possible a screening method to detect auditory disabilities in hyper bilirubinemic infants is of great importance. So the present study is done to know the incidence of hearing loss in hyper bilirubinemic infants & to evaluate the waves I and V in those subjects. METHODS: 45 Infants with hyper bilirubinemia>12mg% & with no other risk factor 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 interpeak latency of I-V were recorded. RESULTS: On one sample t-test, latency of wave I and IPL I-V were significantly increased (p-value <0.001), latency of V was prolonged which was statistically significant (p-value <0.01). Hearing impairment in the affected infants and complete deafness where none of the waves were recorded signify that it is a risk factor for deafness. CONCLUSION: Since hyper bilirubinemia is a risk factor for hearing impairment, their hearing screening by BERA at the earliest will help in their earliest initiation of rehabilitation when the brain is sensitive to the development of speech & language.

Virtual reality walking and dopamine: Opening new doorways to understanding freezing of gait in Parkinson's disease

Freezing of gait (FOG) is a disabling form of gait disturbance that is common in the advanced stages of Parkinson's disease (PD). Despite its prevalence, methods of studying and assessing FOG are limited. We have previously shown that a virtual reality paradigm was able to distinguish between those who report FOG (“freezers”) and those who do not report FOG (“non-freezers”). In this paradigm, ‘freezers’ were found to have prolonged footstep latency in response to known triggers of FOG including doorways, sliding doors and dual-tasking. In this study, we employed the same paradigm to assess performance of 27 freezers and 14 non-freezers in their clinical ‘on’ and ‘off’ medication states. In this study, only participants in the freezing group demonstrated statistically significant increases in latencies experienced in the ‘off’ state compared to the ‘on’ state in response to wide and narrow doorways and the opening of a sliding door. By contrast, these behavioral differences were not apparent in non-freezers. Furthermore the delay was specific to environmental cues and was not due to generalized slowing in the ‘off’ state. The findings suggest that this motor delay when processing environmentally salient cues is specific to freezers and is partially mediated by dopamine-dependent neurocircuitry.

Evaluation of antinociceptive activity of hydromethanol extract of Cyperus rotundus in mice

BackgroundCyperus rotundus Linn. (Cyperaceae) is used to treat inflammation, pain, fever, wounds, boils and blisters in folk medicine. This study evaluated the antinociceptive effect of the hydromethanol extract of whole plant of C. rotundus (HMCR).MethodsThe antinociceptive activity of HMCR was investigated in thermal-induced (hot plate and tail immersion) and chemical-induced (formalin) nociception models in mice at three different doses (50, 100 and 200 mg/kg; p.o.). Morphine sulphate (5 mg/kg, i.p.) and diclofenac sodium (10 mg/kg, i.p.) were used as reference analgesic agents.ResultsIn the hot-plate and tail-immersion tests HMCR significantly increased the latency period to the thermal stimuli at all the tested doses (50, 100 and 200 mg/kg) (p < 0.05). The significant increase in latency is clear from the observations at 60 and 90 min. In formalin-induced paw licking test oral administration of HMCR at 100 and 200 mg/kg doses decreased the licking of paw in early phase. All the tested doses (50, 100 and 200 mg/kg) significantly decreased the licking of paw in late phase of the test (p < 0.001). The dose 200 mg/kg was most effective showing maximum percentage of inhibition of licking in both early (61.60%) and late phase (87.41%).ConclusionThese results indicate the antinociceptive effect of C. rotundus and suggest that this effect is mediated by both peripheral and central mechanisms. These results support the traditional use of this plant in different painful conditions.

Variation in the gaze, caloric test and vestibular-evoked myogenic potential with advancing age

Objectives: The present study was aimed to investigate age related changes on Caloric test, Gaze Test and Vestibular Evoked Myogenic Potential (cVEMP). Materials and Methods: The participants included 50 individuals ranging from 20-70 years having no complaint of dizziness or any major illness. The basic audiological test battery was carried out followed by Caloric test, Gaze Test and the VEMP. Results: There was no consistent pattern seen on the caloric test and gaze test with advancing age while VEMP showed significant increase in latency and decrease in amplitude of both P13 and N23 as the age advances. Discussion: The comparison of the mean SPV values do not show an age related pattern because the caloric test does not challenge the semicircular canal system enough so as to reveal its defects. The age related changes in the cVEMP parameters could be attributed to the age related degeneration in the vestibular sense organ

Memory, learning, and participation of the cholinergic system in young rats exposed to environmental enrichment

The present study demonstrates the consequences of animal exposure to an enriched environment compared to animals living in a standard environment regarding learning and space memory. Male albino Wistar rats were exposed to an enriched environment for 4 weeks after the lactation period and tested in the Morris water maze in the distal and proximal clue version and in the arena. In the former test, the animals were tested at 50 days of age with 12 daily trials on two consecutive days. At the end of each session, scopolamine at the dose of 0.6mg/kg/ml or saline solution was injected intraperitoneally. Twenty-eight days after the first phase, a new test consisting of a single trial was held (retest). An independent group of animals receiving no drug was subjected to the arena test and to the proximal clue version of the Morris maze. In the distal clue version the results did not show differences between groups in the first phase of the experiment. After 28 days (retest), the animals reared in a standard environment and treated with scopolamine exhibited a significant increase in latency compared to the group receiving the same drug and stimulated and to the group receiving saline. The arena data demonstrated a significant increase in exploratory activity in the group of animals reared in an enriched environment. The proximal clue version of the Morris maze did not show differences between groups. The results of the present study indicate that animals exposed to environmental enrichment react less to the amnesic effects of scopolamine and show an increase in exploratory activity.

The effect of finger joint hypomobility on precision grip force

Study designRepeated measures experiment. IntroductionTraumatic injuries and certain other diseases of the hand typically affect mobility of the finger joints. Decreased mobility may alter grip force control while one is grasping and lifting objects. However, the effect of finger joint hypomobility on grip force control has not yet been systematically investigated. Purpose of the studyThe aim of this study was to investigate the effects of limited finger joint mobility, without other associated symptoms like pain, or sensory/proprioceptive deficits, on precision grip force control. MethodsFifteen healthy subjects performed a pinching and lifting task of an object equipped with a force sensor and an accelerometer, via opposition of the thumb and index finger, in the following experimental conditions: unrestricted finger joint movement (UJM), restricted finger flexion (RFF), restricted finger extension (RFE), mock restricted flexion (MRF), mock restricted extension (MRE). The following pinch force variables were measured and analyzed: grip force at lift off, grip force peak, load force peak, latency, and static force. ResultsA significant increase in latency (F = 4.41, p < 0.01) was noted during RFE relative to UJM and MRF conditions. There were no statistically-significant differences between the conditions among the other variables of precision grip force control. ConclusionsLimited joint mobility of the thumb and index finger may cause temporal changes in precision grip force control, which can lead to reduced manual dexterity. Restoring range of motion might be an important priority to improve thumb-index pinch force control during manipulative tasks.