Design, and optimization of COVID-19 hospital wards to produce Oxygen and electricity through solar PV panels with hydrogen storage systems by neural network-genetic algorithm

COVID-19 has affected energy consumption and production pattern in various sectors in both rural and urban areas. Consequently, energy demand has increased. Therefore, most health care centers report a shortage of energy, particularly during the summer seasons. Therefore, integrating renewable energies into hospitals is a promising method that can generate electricity demand reliably and emits less CO2. In this research paper, a hybrid renewable energy system (HRES) with hydrogen energy storage is simulated to cover the energy demand of sections and wards of a hospital that dealt with COVID-19 patients. Produced Oxygen from the hydrogen storage system is captured and stored in medical capsules to generate the oxygen demand for the patients. Results indicate that 29.64% of the annual consumed energy is utilized in COVID-19 sections. Afterward, modeled system has been optimized with a neural network-genetic algorithm to compute the optimum amount of the demand power from the grid, CO2 emission, oxygen capsules, and cost rate. Results determine that by having 976 PV panels, 179 kW fuel cell, and 171.2 kW electrolyzer, annual CO2 emission is 315.8 tons and 67,833 filled medical oxygen capsules can be achieved. The cost rate and demand electricity from the grid for the described system configuration are 469.07 MWh/year and 18.930 EUR/hr, respectively.

Can rice bran, sesame, and olive oils be used as substitutes for soybean oil to improve French salad dressing quality?

Soybean oil is a commonly-used vegetable oil for the industrial manufacture of French salad dressing. The effect of rice bran, sesame, olive, and soybean oils on French salad dressing’s quality characteristics was investigated. After one month, the highest acidity, peroxide value (PV), and the lowest emulsion stability were observed in the control containing soybean oil (p < 0.05). Samples formulated with sesame (T4) and rice bran oils (T3) had the lowest PVs. Color measurement results indicated that a* of a sample containing olive oil (T2) was most influenced and declined on the 30th day (p < 0.05). In the rheological test, samples were solid viscoelastic. The elastic modulus and complex viscosity of T2 were slightly higher. The highest and the lowest overall sensory acceptance belonged to T3 and T2, respectively. Therefore, soybean oil could be replaced to obtain a more desirable product. Finally, T3 was selected as the superior sample.

Sustained ICP Elevation Is a Driver of Spatial Memory Deficits After Intraventricular Hemorrhage and Leads to Activation of Distinct Microglial Signaling Pathways

The mechanisms of cognitive decline after intraventricular hemorrhage (IVH) in some patients continue to be poorly understood. Multiple rodent models of intraventricular or subarachnoid hemorrhage have only shown mild or even no cognitive impairment on subsequent behavioral testing. In this study, we show that intraventricular hemorrhage only leads to a significant spatial memory deficit in the Morris water maze if it occurs in the setting of an elevated intracranial pressure (ICP). Histopathological analysis of these IVH + ICP animals did not show evidence of neuronal degeneration in the hippocampal formation after 2 weeks but instead showed significant microglial activation measured by lacunarity and fractal dimensions. RNA sequencing of the hippocampus showed distinct enrichment of genes in the IVH + ICP group but not in IVH alone having activated microglial signaling pathways. The most significantly activated signaling pathway was the classical complement pathway, which is used by microglia to remove synapses, followed by activation of the Fc receptor and DAP12 pathways. Thus, our study lays the groundwork for identifying signaling pathways that could be targeted to ameliorate behavioral deficits after IVH.

Combined Inhibition of Fyn and c-Src Protects Hippocampal Neurons and Improves Spatial Memory via ROCK after Traumatic Brain Injury

Our previous studies demonstrated that TBI and ventricular administration of thrombin caused hippocampal neuron loss and cognitive dysfunction via activation of Src family kinases (SFKs). Based on SFK localization in brain, we hypothesized SFK subtypes Fyn and c-Src as well as SFK downstream molecule Rho-associated protein kinase (ROCK) contribute to cell death and cognitive dysfunction after TBI. We administered nanoparticle wrapped siRNA-Fyn and siRNA-c-Src, or ROCK inhibitor Y-27632 to adult rats subjected to moderate lateral fluid percussion (LFP) induced TBI. Spatial memory function was assessed from 12 to 16 days, and NeuN stained hippocampal neurons were assessed 16 days after TBI. The combination of siRNA-Fyn and siRNA-c-Src, but neither alone, prevented hippocampal neuron loss and spatial memory deficits after TBI. The ROCK inhibitor Y-27632 also prevented hippocampal neuronal loss and spatial memory deficits after TBI. The data suggest that the combined actions of three kinases (Fyn, c-Src, ROCK) mediate hippocampal neuronal cell death and spatial memory deficits produced by LFP-TBI, and that inhibiting this pathway prevents the TBI-induced cell death and memory deficits.

Allopregnanolone Improves Locomotor Activity and Arousal in the Aged CGG Knock-in Mouse Model of Fragile X-Associated Tremor/Ataxia Syndrome

Carriers of the fragile X premutation (PM) can develop a variety of early neurological symptoms, including depression, anxiety and cognitive impairment as well as being at risk for developing the late-onset fragile X-associated tremor/ataxia syndrome (FXTAS). The absence of effective treatments for FXTAS underscores the importance of developing efficacious therapies to reduce the neurological symptoms in elderly PM carriers and FXTAS patients. A recent preliminary study reported that weekly infusions of Allopregnanolone (Allop) may improve deficits in executive function, learning and memory in FXTAS patients. Based on this study we examined whether Allop would improve neurological function in the aged CGG knock-in (CGG KI) dutch mouse, B6.129P2(Cg)-Fmr1^tm2Cgr/Cgr, that models much of the symptomatology in PM carriers and FXTAS patients. Wild type and CGG KI mice received 10 weekly injections of Allop (10 mg/kg, s.c.), followed by a battery of behavioral tests of motor function, anxiety, and repetitive behavior, and 5-bromo-2'-deoxyuridine (BrdU) labeling to examine adult neurogenesis. The results provided evidence that Allop in CGG KI mice normalized motor performance and reduced thigmotaxis in the open field, normalized repetitive digging behavior in the marble burying test, but did not appear to increase adult neurogenesis in the hippocampus. Considered together, these results support further examination of Allop as a therapeutic strategy in patients with FXTAS.

Early Intervention via Stimulation of the Medial Septal Nucleus Improves Cognition and Alters Markers of Epileptogenesis in Pilocarpine-Induced Epilepsy

Over one-third of patients with temporal lobe epilepsy are refractory to medication. In addition, anti-epileptic drugs often exacerbate cognitive comorbidities. Neuromodulation is an FDA treatment for refractory epilepsy, but patients often wait >20 years for a surgical referral for resection or neuromodulation. Using a rodent model, we test the hypothesis that 2 weeks of theta stimulation of the medial septum acutely following exposure to pilocarpine will alter the course of epileptogenesis resulting in persistent behavioral improvements. Electrodes were implanted in the medial septum, dorsal and ventral hippocampus, and the pre-frontal cortex of pilocarpine-treated rats. Rats received 30 min/day of 7.7 Hz or theta burst frequency on days 4-16 post-pilocarpine, prior to the development of spontaneous seizures. Seizure threshold, spikes, and oscillatory activity, as well as spatial and object-based learning, were assessed in the weeks following stimulation. Non-stimulated pilocarpine animals exhibited significantly decreased seizure threshold, increased spikes, and cognitive impairments as compared to vehicle controls. Furthermore, decreased ventral hippocampal power (6-10 Hz) correlated with both the development of spikes and impaired cognition. Measures of spikes, seizure threshold, and cognitive performance in both acute 7.7 Hz and theta burst stimulated animals were statistically similar to vehicle controls when tested during the chronic phase of epilepsy, weeks after stimulation was terminated. These data indicate that modulation of the septohippocampal circuit early after pilocarpine treatment alters the progression of epileptic activity, resulting in elevated seizure thresholds, fewer spikes, and improved cognitive outcome. Results from this study support that septal theta stimulation has the potential to serve in combination or as an alternative to high frequency thalamic stimulation in refractory cases and that further research into early intervention is critical.

Recovery of Theta Frequency Oscillations in Rats Following Lateral Fluid Percussion Corresponds With a Mild Cognitive Phenotype

Whether from a fall, sports concussion, or even combat injury, there is a critical need to identify when an individual is able to return to play or work following traumatic brain injury (TBI). Electroencephalogram (EEG) and local field potentials (LFP) represent potential tools to monitor circuit-level abnormalities related to learning and memory: specifically, theta oscillations can be readily observed and play a critical role in cognition. Following moderate traumatic brain injury in the rat, lasting changes in theta oscillations coincide with deficits in spatial learning. We hypothesized, therefore, that theta oscillations can be used as an objective biomarker of recovery, with a return of oscillatory activity corresponding with improved spatial learning. In the current study, LFP were recorded from dorsal hippocampus and anterior cingulate in awake, behaving adult Sprague Dawley rats in both a novel environment on post-injury days 3 and 7, and Barnes maze spatial navigation on post-injury days 8–11. Theta oscillations, as measured by power, theta-delta ratio, peak theta frequency, and phase coherence, were significantly altered on day 3, but had largely recovered by day 7 post-injury. Injured rats had a mild behavioral phenotype and were not different from shams on the Barnes maze, as measured by escape latency. Injured rats did use suboptimal search strategies. Combined with our previous findings that demonstrated a correlation between persistent alterations in theta oscillations and spatial learning deficits, these new data suggest that neural oscillations, and particularly theta oscillations, have potential as a biomarker to monitor recovery of brain function following TBI. Specifically, we now demonstrate that oscillations are depressed following injury, but as oscillations recover, so does behavior.

Comparison of in vitro antifungal activity of novel triazoles with available antifungal agents against dermatophyte species caused tinea pedis

OBJECTIVE

Dermatophytes are a group of keratinophilic fungi that invade and infect the keratinized tissues and cause dermatophytosis. We investigated effectiveness of novel triazole (luliconazole and lanaconazole) in comparison with available antifungal agents against dermatophyte species isolated from patients with tinea pedis.

MATERIAL AND METHODS

A total of 60 dermatophytes species were isolated from the patients with tinea pedis. Identification of species was done by DNA sequencing of the ITS1-5.8S rDNA-ITS2 rDNA region. In vitro antifungal susceptibility testing with luliconazole and lanaconazole and available antifungal agent was done in accordance with the Clinical and Laboratory Standards Institute, M38-A2 document.

RESULTS

In all investigated isolates, luliconazole had the lowest minimum inhibitory concentration (MIC) (MIC range=0.0005-0.004μg/mL), while fluconazole (MIC range=0.4-64μg/mL) had the highest MICs. Geometric mean MIC was the lowest for luliconazole (0.0008μg/mL), followed by lanoconazole (0.003μg/mL), terbinafine (0.019μg/mL), itraconazole (0.085 μg/mL), ketoconazole (0.089μg/mL), econazole (0.097μg/mL), griseofulvin (0.351 μg/mL), voriconazole (0.583μg/mL) and fluconazole (11.58μg/mL).

CONCLUSION

The novel triazoles showed potent activity against dermatophytes and promising candidates for the treatment of tinea pedis caused by Trichophyton and Epidermophyton species. However, further studies are warranted to determine the clinical implications of these investigations.

Medial septal stimulation increases seizure threshold and improves cognition in epileptic rats

BACKGROUND

Temporal lobe epilepsy is most prevalent among focal epilepsies, and nearly one-third of patients are refractory to pharmacological intervention. Persistent cognitive and neurobehavioral comorbidities also occur due to the recurrent nature of seizures and medication-related side effects.

HYPOTHESIS

Electrical neuromodulation is an effective strategy to reduce seizures both in animal models and clinically, but its efficacy to modulate cognition remains unclear. We hypothesized that theta frequency stimulation of the medial septum would increase septohippocampal oscillations, increase seizure threshold, and improve spatial learning in a rat model of pilocarpine-induced epilepsy.

METHODS

Sham and pilocarpine rats were implanted with electrodes in the medial septum, hippocampus and prefrontal cortex. EEG was assessed days prior to and following stimulation. Sham and pilocarpine-treated rats received either no stimulation, continuous (throughout each behavior), or pre-task (one minute prior to each behavior) 7.7 Hz septal stimulation during the Barnes maze spatial navigation test and also during assessment of flurothyl-induced seizures.

RESULTS

Both continuous and pre-task stimulation prevented epilepsy-associated reductions in theta oscillations over time. Additionally, both stimulation paradigms significantly improved spatial navigation in the Barnes maze, reducing latency and improving search strategy. Moreover, stimulation led to significant increases in seizure threshold in pilocarpine-treated rats. There was no evidence of cognitive enhancement or increased seizure threshold in stimulated sham rats.

CONCLUSION

These findings have profound implications as theta stimulation of the septum represents a single frequency and target that has the potential to both improve cognition and reduce seizures for patients with refractory epilepsy.

Treatment of paper-recycling wastewater by electrocoagulation using aluminum and iron electrodes

Treatment of industrial wastewater by electrocoagulation (EC) is one of the most efficient methods to remove pollutants. Paper-recycling wastewater is a complex mixture containing toxic and recalcitrant substances, indicating complexity and difficulty of its treatment. The aim of the present study was to assess the effectiveness of paper-recycling wastewater treatment by EC process using aluminum (Al) and iron (Fe) plate electrodes. Removal of chemical oxygen demand (COD), total suspended solids (TSS), color and ammonia from paper-recycling mill effluent was evaluated at various electrolysis times (10-60 min), voltage (4-13 V) and pH (3.5-11). The optimum process conditions for the maximum removal of COD, TSS, color and ammonia from paper-recycling industry wastewater have been found to be pH value of 7, treatment time of 60 min and voltage of 10 V. Under optimum operating conditions, the removal capacities of COD, TSS, color and ammonia were 79.5%, 83.4%, 98.5% and 85.3%, respectively. It can be concluded that EC could be considered as an effective alternative for treatment of paper-recycling wastewater.

Clinically indicated electrical stimulation strategies to treat patients with medically refractory epilepsy

Focal epilepsies represent approximately half of all diagnoses, and more than one-third of these patients are refractory to pharmacologic treatment. Although resection can result in seizure freedom, many patients do not meet surgical criteria, as seizures may be multifocal in origin or have a focus in an eloquent region of the brain. For these individuals, several U.S. Food and Drug Administration (FDA)-approved electrical stimulation paradigms serve as alternative options, including vagus nerve stimulation, responsive neurostimulation, and stimulation of the anterior nucleus of the thalamus. All of these are safe, flexible, and lead to progressive seizure control over time when used as an adjunctive therapy to antiepileptic drugs. Focal epilepsies frequently involve significant comorbidities such as cognitive decline. Similar to antiepilepsy medications and surgical resection, current stimulation targets and parameters have yet to address cognitive impairments directly, with patients reporting persistent comorbidities associated with focal epilepsy despite a significant reduction in the number of their seizures. Although low-frequency theta oscillations of the septohippocampal network are critical for modulating cellular activity and, in turn, cognitive processing, the coordination of neural excitability is also imperative for preventing seizures. In this review, we summarize current FDA-approved electrical stimulation paradigms and propose that theta oscillations of the medial septal nucleus represent a novel neuromodulation target for concurrent seizure reduction and cognitive improvement in epilepsy. Ultimately, further advancements in clinical neurostimulation strategies will allow for the efficient treatment of both seizures and comorbidities, thereby improving overall quality of life for patients with epilepsy.

Stimulation of the medial septum improves performance in spatial learning following pilocarpine-induced status epilepticus

Temporal lobe epilepsy often leads to hippocampal sclerosis and persistent cognitive deficits, including difficulty with learning and memory. Hippocampal theta oscillations are critical in optimizing hippocampal function and facilitating plasticity. We hypothesized that pilocarpine-induced status epilepticus would disrupt oscillations and behavioral performance and that electrical neuromodulation to entrain theta would improve cognition specifically in injured rats. Rats received a pilocarpine (n=30) or saline injection (n=27) and unilateral bi-polar electrodes were implanted into the medial septum and hippocampus the following day. Hippocampal and septal theta were recorded in a Plexiglas box over the first week following implantation. Control and pilocarpine-treated rats were split into stimulation (continuous 7.7Hz, 80μA, 1ms pulse width) and non-stimulation groups for behavioral analysis. Continuous stimulation was initiated one-minute prior to and throughout an object exploration task (post-injury day seven) and again for each of six trials on the Barnes maze (post-injury days 12-14). There was a significant reduction in hippocampal theta power (p<0.05) and percentage of time oscillating in theta (p<0.05). In addition there was a significant decrease in object exploration in rats post-pilocarpine (p<0.05) and an impairment in spatial learning. Specifically, pilocarpine-treated rats were more likely to use random search strategies (p<0.001) and had an increase in latency to find the hidden platform (p<0.05) on the Barnes maze. Stimulation of the medial septum at 7.7Hz in pilocarpine-treated rats resulted in performance similar to shams in both the object recognition and Barnes maze tasks. Stimulation of sham rats resulted in impaired object exploration (p<0.05) with no difference in Barnes maze latency or strategy. In conclusion, pilocarpine-induced seizures diminished hippocampal oscillations and impaired performance in both an object exploration and a spatial memory task in pilocarpine-treated rats. Theta stimulation at 7.7Hz improved behavioral outcome on the Barnes maze task; this improvement in function was not related to a general cognitive enhancement, as shams did not benefit from stimulation. Therefore, stimulation of the medial septum represents an exciting target to improve behavioral outcome in patients with epilepsy.

Making Waves in the Brain: What Are Oscillations, and Why Modulating Them Makes Sense for Brain Injury

Traumatic brain injury (TBI) can result in persistent cognitive, behavioral and emotional deficits. However, the vast majority of patients are not chronically hospitalized; rather they have to manage their disabilities once they are discharged to home. Promoting recovery to pre-injury level is important from a patient care as well as a societal perspective. Electrical neuromodulation is one approach that has shown promise in alleviating symptoms associated with neurological disorders such as in Parkinson’s disease (PD) and epilepsy. Consistent with this perspective, both animal and clinical studies have revealed that TBI alters physiological oscillatory rhythms. More recently several studies demonstrated that low frequency stimulation improves cognitive outcome in models of TBI. Specifically, stimulation of the septohippocampal circuit in the theta frequency entrained oscillations and improved spatial learning following TBI. In order to evaluate the potential of electrical deep brain stimulation for clinical translation we review the basic neurophysiology of oscillations, their role in cognition and how they are changed post-TBI. Furthermore, we highlight several factors for future pre-clinical and clinical studies to consider, with the hope that it will promote a hypothesis driven approach to subsequent experimental designs and ultimately successful translation to improve outcome in patients with TBI.

Septohippocampal Neuromodulation Improves Cognition after Traumatic Brain Injury

Traumatic brain injury (TBI) often results in persistent attention and memory deficits that are associated with hippocampal dysfunction. Although deep brain stimulation (DBS) is used to treat neurological disorders related to motor dysfunction, the effectiveness of stimulation to treat cognition remains largely unknown. In this study, adult male Harlan Sprague-Dawley rats underwent a lateral fluid percussion or sham injury followed by implantation of bipolar electrodes in the medial septal nucleus (MSN) and ipsilateral hippocampus. In the first week after injury, there was a significant decrease in hippocampal theta oscillations that correlated with decreased object exploration and impaired performance in the Barnes maze spatial learning task. Continuous 7.7 Hz theta stimulation of the medial septum significantly increased hippocampal theta oscillations, restored normal object exploration, and improved spatial learning in injured animals. There were no benefits with 100 Hz gamma stimulation, and stimulation of sham animals at either frequency did not enhance performance. We conclude, therefore, that there was a theta frequency-specific benefit of DBS that restored cognitive function in brain-injured rats. These data suggest that septal theta stimulation may be an effective and novel neuromodulatory therapy for treatment of persistent cognitive deficits following TBI.

Plasma levels of Transforming Growth Factor Beta in HIV-1 patients with oral candidiasis

BACKGROUND AND PURPOSE

TGF-β is a potent regulator and suppressor of the immune system and overproduction of this cytokine may contribute to immunosuppression in HIV-infected patients. Increasing population of immunosuppressed patients has resulted in increasingly frequent of fungal infections, including oral candidiasis. The aim of this study was to evaluate the plasma levels of TGF-β under in vivo conditions.

MATERIALS AND METHODS

Seventy- two samples were obtained from the oral cavities of HIV-positive Iranian patients and cultured on Sabouraud's dextrose agar and CHROMagar. Also blood samples were obtained to assess TGF-β levels using ELISA technique.

RESULTS

Thirty-three out of 72 oral samples yielded candida isolates, Candida albicans in 14 and non-albicans candida in 19.Fungal infection decreased significantly more TGF-β level than non-fungal infection also HIV negative were significantly more TGF-β than HIV positive.

CONCLUSION

Our findings suggest a significant interaction between fungal infection and HIV on expression of Transforming Growth Factor Beta.

Abstract T P234: Cell Cycle Inhibition via Blocking Src Family Kinases Promotes Hippocampal Neuron Survival and Improves Cognitive Function after Intraventricular Hemorrhage

Intraventricular hemorrhage (IVH) is one of the most serious hemorrhagic brain diseases being associated with blood brain barrier (BBB) disruption, brain edema, neuron loss, cognitive impairment and high mortality in humans. Increasing evidence suggests that neuronal cell death ensues when neurons attempt to re-enter the cell cycle. Our previous study has demonstrated that cell cycle inhibition via blocking Src family kinases (SFKs) prevents neuronal cell death. However, one of the concerns with cell cycle therapy might be that it would inhibit proliferation of neural progenitor cells (NPCs) and that inhibiting neurogenesis would produce cognitive effects related to the therapy itself.

Using the rodent in vivo IVH model we show that i.p. injection of SFK inhibitor (PP2) prevents IVH-induced death of hippocampal neurons and cognitive deficits assessed on the Morris Water Maze. Moreover, PP2 (i.p.) alone did not affect proliferation of NPCs and did not affect cognition. Since there are several SFK gene family members in brain, we targeted specific SFK subtypes (e.g. Fyn, Lck and c-Src) using a newly developed in vivo nanoparticle-based siRNA transfection system. We show that nanoparticle-siRNA-Fyn plus nanoparticle-siRNA-Src attenuate IVH-induced neuron loss and cognitive deficits. Nanoparticle-siRNA-Fyn nor nanoparticle-siRNA-Src had no significant affects on population of NPCs or cognitive side effects, possibly because the nanoparticle-based siRNA transfection system only produces transient knockdown of the gene targets. This could provide a novel therapy for treating IVH patients as the nanoparticle-based siRNA approach provides heightened specificity for specific SFK gene(s) with less off target effects and this approach has been used in humans.

Acknowledgements: This study was supported by AHA Beginning Grant-in-Aid 12BGIA12060381 (DZL) and NIH grant NS054652 (FRS). There were no conflicts of interest.

Medial septal nucleus theta frequency deep brain stimulation improves spatial working memory after traumatic brain injury

More than 5,000,000 survivors of traumatic brain injury (TBI) live with persistent cognitive deficits, some of which likely derive from hippocampal dysfunction. Oscillatory activity in the hippocampus is critical for normal learning and memory functions, and can be modulated using deep brain stimulation techniques. In this pre-clinical study, we demonstrate that lateral fluid percussion TBI results in the attenuation of hippocampal theta oscillations in the first 6 days after injury, which correlate with deficits in the Barnes maze spatial working memory task. Theta band stimulation of the medial septal nucleus (MSN) results in a transient increase in hippocampal theta activity, and when delivered 1 min prior to training in the Barnes maze, it significantly improves spatial working memory. These results suggest that MSN theta stimulation may be an effective neuromodulatory technique for treatment of persistent learning and memory deficits after TBI.

A comparative study of human and rat hippocampal low-frequency oscillations during spatial navigation

Rhythmic oscillations within the 3-12 Hz theta frequency band manifest in the rodent hippocampus during a variety of behaviors and are particularly well characterized during spatial navigation. In contrast, previous studies of rhythmic hippocampal activity in primates under comparable behavioral conditions suggest it may be less apparent and possibly less prevalent, or even absent, compared with the rodent. We compared the relative presence of low-frequency oscillations in rats and humans during spatial navigation by using an oscillation detection algorithm ("P-episode" or "BOSC") to better characterize their presence in microelectrode local field potential (LFP) recordings. This method quantifies the proportion of time the LFP exceeds both a power and cycle duration threshold at each frequency, characterizing the presence of (1) oscillatory activity compared with background noise, (2) the peak frequency of oscillatory activity, and (3) the duration of oscillatory activity. Results demonstrate that both humans and rodents have hippocampal rhythmic fluctuations lasting, on average, 2.75 and 4.3 cycles, respectively. Analyses further suggest that human hippocampal rhythmicity is centered around ∼3 Hz while that of rats is centered around ∼8 Hz. These results establish that low-frequency rhythms relevant to spatial navigation are present in both the rodent and human hippocampus, albeit with different properties under the behavioral conditions tested.

NAAG peptidase inhibitor improves motor function and reduces cognitive dysfunction in a model of TBI with secondary hypoxia

Immediately following traumatic brain injury (TBI) and TBI with hypoxia, there is a rapid and pathophysiological increase in extracellular glutamate, subsequent neuronal damage and ultimately diminished motor and cognitive function. N-acetyl-aspartyl glutamate (NAAG), a prevalent neuropeptide in the CNS, is co-released with glutamate, binds to the presynaptic group II metabotropic glutamate receptor subtype 3 (mGluR3) and suppresses glutamate release. However, the catalytic enzyme glutamate carboxypeptidase II (GCP II) rapidly hydrolyzes NAAG into NAA and glutamate. Inhibition of the GCP II enzyme with NAAG peptidase inhibitors reduces the concentration of glutamate both by increasing the duration of NAAG activity on mGluR3 and by reducing degradation into NAA and glutamate resulting in reduced cell death in models of TBI and TBI with hypoxia. In the following study, rats were administered the NAAG peptidase inhibitor PGI-02776 (10mg/kg) 30 min following TBI combined with a hypoxic second insult. Over the two weeks following injury, PGI-02776-treated rats had significantly improved motor function as measured by increased duration on the rota-rod and a trend toward improved performance on the beam walk. Furthermore, two weeks post-injury, PGI-02776-treated animals had a significant decrease in latency to find the target platform in the Morris water maze as compared to vehicle-treated animals. These findings demonstrate that the application of NAAG peptidase inhibitors can reduce the deleterious motor and cognitive effects of TBI combined with a second hypoxic insult in the weeks following injury.

Abstract 2357: Src Kinase Inhibition Blocks Thrombin-induced Brain Injuries without Cognitive Side Effects

Intracerebral hemorrhage (ICH) activates thrombin, a potent mitogen. Thrombin triggers mitosis by modulating several intracellular mitogenic molecules including Src family kinases. These molecules regulate mitogen-activated protein kinases (MAPKs) and cell cycle proteins such as cyclin-dependent kinases (Cdks); and play critical roles in mitogenic signaling pathways and cell cycle progression. Since aberrant cell cycle reentry results in death of mature neurons, cell cycle inhibition appears to be a candidate strategy for the treatment of neurological diseases including ICH. However, this can also block cell cycle (proliferation) of neural progenitor cells (NPCs) and thus impair brain neurogenesis leading to cognitive deficits. We hypothesized that inhibition of cell cycle by blocking mitogenic signaling molecules (i.e., Src family kinase members) blocks cell cycle reentry of mature neurons without injuring NPCs, which will avoid cognitive side effects during cell cycle inhibition treatment for ICH. Our data shows: (1) Thrombin 30U/ml results in apoptosis of mature neurons via neuronal cell cycle reentry in vitro ; (2) PP2 (Src family kinase inhibitor) 0.3 µM attenuates the thrombin-induced neuronal apoptosis via blocking neuronal cell cycle reentry, but does not affect the viability of NPCs at the same doses in vitro ; (3) Intracerebral ventricular thrombin injection (20U, i.c.v.) results in neuron loss in hippocampus and cognitive deficits 5 weeks after thrombin injection in vivo ; (4) PP2 (1mg/kg, i.p.), given immediately after thrombin injection (i.c.v.), blocks the thrombin-induced neuron loss in hippocampus and cognitive deficits, whereas PP2 on its own at the same doses does not affect normal cognition in vivo . These suggest that Src kinase inhibition prevents hippocampal neuron death via blocking neuronal cell cycle reentry after ICH, but does not affect survival of NPCs.

Effects of mitomycin C on corneal endothelial cell counts in pterygium surgery: role of application location

PURPOSE

To evaluate changes in corneal endothelial cell counts after pterygium surgery with application of mitomycin C (MMC) either on the perilimbal sclera or in the subconjunctival space.

DESIGN

Prospective, randomized interventional study.

METHODS

Fifty-six eyes of 56 patients with primary pterygium underwent excision followed by removal of subconjunctival fibrovascular tissue, 0.02% MMC application, and amniotic membrane transplantation. These were stratified randomly into 2 groups. In 1 group (n = 28), MMC was applied on the perilimbal bare sclera (sclera group), and in other group (n = 28), MMC was applied under conjunctiva, where subconjunctival fibrovascular tissue was removed (subconjunctiva group). Based on severity of pterygium fleshiness, MMC was used for 1, 3, or 5 minutes in 8, 13, and 7 eyes, respectively, in the sclera group and in 9, 13, and 6 eyes, respectively, in the subconjunctiva group. Central corneal endothelial cell counts were evaluated before and during 6 months of follow-up after surgery.

RESULTS

Mean preoperative endothelial cell count was 2810 ± 278 cells/mm(2) in the sclera group and 2857 ± 332 cells/mm(2) in the subconjunctiva group. Mean endothelial cell losses in sclera and subconjunctiva groups were 9.7% and 9.0% at 1 week, 6.5% and 6.5% at 1 month, 4.0% and 5.0% at 3 months, and 3.4% and 4.8% at 6 months, respectively, with no statistically significant difference between the 2 groups. Longer durations of MMC application were associated with significantly greater endothelial losses in both groups.

CONCLUSIONS

Regardless of application location, MMC use during pterygium surgery can cause a significant decrease in central endothelial cell count.