Involvement of orexin type-2 receptors in genetic absence epilepsy rats.

Introduction: Orexin is a neuropeptide neurotransmitter that regulates the sleep/wake cycle produced by the lateral hypothalamus neurons. Recent studies have shown the involvement of orexin system in epilepsy. Limited data is available about the possible role of orexins in the pathophysiology of absence seizures. This study aims to understand the role of orexinergic signaling through the orexin-type 2 receptor (OX2R) in the pathophysiology of absence epilepsy. The pharmacological effect of a selective OX2R agonist, YNT-185 on spike-and-wave-discharges (SWDs) and the OX2R receptor protein levels in the cortex and thalamus in adult GAERS were investigated. Methods: The effect of intracerebroventricular (ICV) (100, 300, and 600 nmol/10 µL), intrathalamic (30 and 40 nmol/500 nL), and intracortical (40 nmol/500 nL) microinjections of YNT-185 on the duration and number of spontaneous SWDs were evaluated in adult GAERS. The percentage of slow-wave sleep (SWS) and spectral characteristics of background EEG were analyzed after the ICV application of 600 nmol YNT-185. The level of OX2R expression in the somatosensory cortex and projecting thalamic nuclei of adult GAERS were examined by Western blot and compared with the non-epileptic Wistar rats. Results: We showed that ICV administration of YNT-185 suppressed the cumulative duration of SWDs in GAERS compared to the saline-administered control group (p < 0.05). However, intrathalamic and intracortical microinjections of YNT-185 did not show a significant effect on SWDs. ICV microinjections of YNT-185 affect sleep states by increasing the percentage of SWS and showed a significant treatment effect on the 1-4 Hz delta frequency band power during the 1-2 h post-injection period where YNT-185 significantly decreased the SWDs. OXR2 protein levels were significantly reduced in the cortex and thalamus of GAERS when compared to Wistar rats. Conclusion: This study investigated the efficacy of YNT-185 for the first time on absence epilepsy in GAERS and revealed a suppressive effect of OX2R agonist on SWDs as evidenced by the significantly reduced expression of OX2R in the cortex and thalamus. YNT-185 effect on SWDs could be attributed to its regulation of wake/sleep states. The results constitute a step toward understanding the effectiveness of orexin neuropeptides on absence seizures in GAERS and might be targeted by therapeutic intervention for absence epilepsy.

The correlation between death anxiety, loneliness and hope levels in patients treated in the cardiac intensive care unit.

BACKGROUND: A sense of hope plays an important role in relieving stress and psychological distress of cardiology patients, as well as improving their physical well-being. AIM: The aim of this study is to investigate the correlation between death anxiety, loneliness and hope levels in patients receiving treatment in a cardiac intensive care unit (ICU). DESIGN: This is a prospective, descriptive and correlational study. METHODS: The study was completed with 150 cardiac ICU patients in Istanbul, Turkey. The data were collected using a Patient Information Form, the Templer Death Anxiety Scale (TDAS), the Herth Hope Index (HHI) and the UCLA Loneliness Scale (UCLA-LS). RESULTS: The patients had a mean age of 63.56 ± 12.74 years. Most of the patients (82%) were treated in the ICU for heart failure. There was a statistically significant positive correlation between total scores of TDAS and UCLA-LS (r = .337; p < .001) and a statistically significant negative correlation between total scores of UCLA-LS and HHI (r = -.292; p < .001). Also, there was a statistically significant negative correlation between the scores of UCLA-LS and Positive Readiness and Expectancy Subscale (r = -.164; p = .044). The multiple linear regression indicated that the model was statistically significant (F = 7.177, p < .001). The variables of age and UCLA-LS among those included in the model were statistically significant predictors of the death anxiety scores of the patients (23.1%) (p < .05). CONCLUSIONS: The cardiology patients who received treatment in the ICU had a high level of death anxiety and moderate levels of loneliness and hope. The age and loneliness level were statistically significant predictors of death anxiety. RELEVANCE TO CLINICAL PRACTICE: It is recommended that individualized nursing care be planned and provided to conscious cardiology patients who are treated in the ICU, considering their age and loneliness levels and that nursing care be planned for individuals who are at risk of fear, anxiety, loneliness and hopelessness by periodically assessing their death anxiety, loneliness and hope levels.

Socially assistive robots in health and social care: Acceptance and cultural factors. Results from an exploratory international online survey.

AIM: This study explored the views of an international sample of registered nurses and midwives working in health and social care concerning socially assistive robots (SARs), and the relationship between dimensions of culture and rejection of the idea that SARs had benefits in these settings. METHODS: An online survey was used to obtain rankings of (among other topics) the extent to which SARs have benefits for health and social care. It also asked for free text responses regarding any concerns about SARs. RESULTS: Most respondents were overwhelmingly positive about SARs' benefits. A small minority strongly rejected this idea, and qualitative analysis of the objections raised by them revealed three major themes: things might go wrong, depersonalization, and patient-related concerns. However, many participants who were highly accepting of the benefits of SARs expressed similar objections. Cultural dimensions of long-term orientation and uncertainty avoidance feature prominently in technology acceptance research. Therefore, the relationship between the proportion of respondents from each country who felt that SARs had no benefits and each country's ratings on long-term orientation and uncertainty avoidance were also examined. A significant positive correlation was found for long-term orientation, but not for uncertainty avoidance. CONCLUSION: Most respondents were positive about the benefits of SARs, and similar concerns about their use were expressed both by those who strongly accepted the idea that they had benefits and those who did not. Some evidence was found to suggest that cultural factors were related to rejecting the idea that SARs had benefits.

Enactment of compassionate leadership by nursing and midwifery managers: results from an international online survey.

AIM: To explore the views of an international sample of nursing and midwifery managers concerning attributes that they associate with compassionate management. METHOD: A cross-sectional online survey. Using a snowballing sampling method, 1217 responses were collected from nursing and midwifery managers in 17 countries. A total of complete 933 responses to a question related to which actions and behaviours indicated that a manager was exercising compassionate leadership were analysed for this paper. First, content analysis of the responses was conducted, and second, a relative distribution of the identified themes for the overall sample and for each participating country was calculated. RESULTS: Six main themes were identified describing the attributes of a compassionate leader: (1) Virtuous support, (2) Communication, (3) Personal virtues of the manager, (4) Participatory communication, (5) Growth/flourishing/ nurturing and (6) Team cohesion. The first three themes mentioned above collectively accounted for 63% of the responses, and can therefore be considered to be the most important characteristics of compassionate management behaviour. CONCLUSION: The key indicators of compassionate management in nursing and midwifery which were identified emphasise approachability, active and sensitive listening, sympathetic responses to staff members' difficulties (especially concerning child and other caring responsibilities), active support of and advocacy for the staff team and active problem solving and conflict resolution. While there were differences between the countries' views on compassionate healthcare management, some themes were widely represented among different countries' responses, which suggest key indicators of compassionate management that apply across cultures.

The effect of chronic treatment with sodium channel blocker lacosamide on early development of absence seizures in genetic absence epilepsy rats.

OBJECTIVE: Lacosamide (LCM) is a new generation antiepileptic drug that affects the slow inactivation of voltage-gated sodium channels. We studied whether chronic LCM treatment prior to onset of absence seizures was able to prevent/reduce the development of absence seizures in GAERS rats, a well-validated animal model of absence epilepsy and epileptogenesis. Drug effects on the duration, mean duration, number and spectral characteristics of spike-wave discharges (SWDs) were measured both 1 and 2 months after treatment withdrawal and compared with the ethosuximide (ETX) that has anti-epileptogenic activity in GAERS. Furthermore, the acute effects of LCM on SWDs in adult GAERS were evaluated. METHODS: GAERS rats were administered either with LCM (10 mg/kg/day or 30 mg/kg/day, i.p) or ETX (25 mg/kg/day, i.p) or saline (%0.9 NaCl) until PN60 for 40 consecutive days starting from PN20. Animals were stereotaxically implanted with cortical screw electrodes under ketamine/xylazine anesthesia at PN53. Following recovery period, EEG were recorded at PN60 (last day of drug administration)- 61-62, PN90-91-92 and PN120-121-122 time periods for 3 consecutive days. RESULTS: The chronic treatment with both LCM and ETX led to an ∼50% reduction in the development of spontaneous absence seizures in GAERS at PN90 and PN120 after the treatment withdrawal at PN60. The spectral analysis of EEG data revealed significant slowing of the peak frequency of SWDs in LCM treated animals at PN62. CONCLUSION: These results confirm that chronic LCM treatment modifies the development of absence seizures in GAERS and suggest that LCM exerts beneficial effects on absence seizure epileptogenesis.

Antiepileptogenic effects of rapamycin in a model of infantile spasms due to structural lesions.

OBJECTIVE: Infantile spasms may evolve into persistent epilepsies including Lennox-Gastaut syndrome. We compared adult epilepsy outcomes in models of infantile spasms due to structural etiology (multiple-hit model) or focal cortical inflammation and determined the anti-epileptogenic effects of pulse-rapamycin, previously shown to stop spasms in multiple-hit rats. METHODS: Spasms were induced in 3-day-old male rats via right intracerebral doxorubicin/lipopolysaccharide (multiple-hit model) infusions. Controls and sham rats were used. Separate multiple-hit rats received pulse-rapamycin or vehicle intraperitoneally between postnatal days 4 and 6. In adult mice, video-EEG (electroencephalography) scoring for seizures and sleep and histology were done blinded to treatment. RESULTS: Motor-type seizures developed in 66.7% of multiple-hit rats, usually from sleep, but were reduced in the pulse-rapamycin-treated group (20%, p = .043 vs multiple-hit) and rare in other groups (0-9.1%, p < .05 vs multiple-hit). Spike-and-wave bursts had a slower frequency in multiple-hit rats (5.4-5.8Hz) than in the other groups (7.6-8.3Hz) (p < .05); pulse rapamycin had no effect on the hourly spike-and-wave burst rates in adulthood. Rapamycin, however, reduced the time spent in slow-wave-sleep (17.2%), which was increased in multiple-hit rats (71.6%, p = .003). Sham rats spent more time in wakefulness (43.7%) compared to controls (30.6%, p = .043). Multiple-hit rats, with or without rapamycin treatment, had right more than left corticohippocampal, basal ganglia lesions. There was no macroscopic pathology in the other groups. SIGNIFICANCE: Structural corticohippocampal/basal ganglia lesions increase the risk for post-infantile spasms epilepsy, Lennox-Gastaut syndrome features, and sleep dysregulation. Pulse rapamycin treatment for infantile spasms has anti-epileptogenic effects, despite the structural lesions, and decreases the time spent in slow wave sleep.

The Importance of Being a Compassionate Leader: The Views of Nursing and Midwifery Managers From Around the World.

INTRODUCTION: Despite the importance of compassionate leadership in health care, many of the existing publications do not account for the effect of culture. The aim of this study is to explore the views of nursing and midwifery managers from different countries in relation to the definition, advantages, and importance of compassion. METHODOLOGY: A cross-sectional, descriptive, exploratory online survey was conducted across 17 countries, containing both closed and open-ended questions. Data from N = 1,217 respondents were analyzed using a directed hybrid approach focusing only on qualitative questions related to compassion-giving. RESULTS: Four overarching themes capture the study's results: (1) definition of compassion, (2) advantages and importance of compassion for managers, (3) advantages and importance of compassion for staff and the workplace, and (4) culturally competent and compassionate leadership. DISCUSSION: Innovative research agendas should pursue further local qualitative empirical research to inform models of culturally competent and compassionate leadership helping mangers navigate multiple pressures and be able to transculturally resonate with their staff and patients.

Agmatine has beneficial effect on harmaline-induced essential tremor in rat.

Essential tremor (ET) is one of the most prevalent movement disorders and the most common cause of abnormal tremors. However, it cannot be treated efficiently with the currently available pharmacotherapy options. The pathophysiology of harmaline-induced tremor, most commonly used model of ET, involves various neurotransmitter systems including glutamate as well as ion channels. Agmatine, an endogenous neuromodulator, interacts with various glutamate receptor subtypes and ion channels, which have been associated with its' beneficial effects on several neurological disorders. The current study aims to assess the effect of agmatine on the harmaline model of ET. Two separate groups of male rats were injected either with saline or agmatine (40 mg/kg) 30 min prior to single intraperitoneal injection of harmaline (20 mg/kg). The percent duration, intensity and frequency of tremor and locomotor activity were evaluated by a custom-built tremor and locomotion analysis system. Pretreatment with agmatine reduced the percent tremor duration and intensity of tremor induced by harmaline, without affecting the tremor frequency. However, it did not affect the decreased spontaneous locomotor activity due to harmaline. This pattern of ameliorating effects of agmatine on harmaline-induced tremor provide the first evidence for being considered as a treatment option for ET.

Attitudes of three generations of women toward gender roles.

PURPOSE: This study was conducted to investigate the attitudes of three generations of women regarding gender roles. DESIGNS AND METHODS: In this study, 58 female students, their mothers, and grandmothers participated. Percentages and means, χ2 test, Kruskal Wallis test, and multiple regression analysis were used to analyze the data. FINDINGS: The findings obtained in this study showed that 91.5% of the students, 89.8% of the mothers, and 84.6% of the grandmothers had an egalitarian attitude regarding gender roles. The egalitarian attitudes of students were affected onefold by the attitudes of mothers, whereas grandmothers' attitudes affected the attitudes of students 1.1 times. These two variables explain 48% of the status of having egalitarian attitudes of the students. PRACTICAL IMPLICATIONS: Students had more traditional attitudes regarding gender roles than their mothers and grandmothers.

The Effect of COVID-19 Pandemic on Death Anxiety of Nursing Students.

BACKGROUND: It is required to determine death anxiety of nursing students so that they who will become healthcare professionals can cope with the fast-spreading and high-mortality diseases such as COVID-19 infection upon graduation, can communicate with infected and dying patients, and can provide patients with the necessary support and care. The purpose of this study is to determine the death anxiety experienced by nursing students due to COVID-19, the related factors. SUBJECTS AND METHODS: This descriptive and correlational study was completed between June and September 2020. The data were collected by using the Socio-demographic and COVID-19 Pandemic Information Form and Death Anxiety Scale (DAS). The student nurses who agreed to participate in the study were asked to fill out an online questionnaire that was sent by the researchers. The study was conducted with 115 nursing students. RESULTS: The DAS mean scores of the nursing students were found to be 8.01±1.96. When the correlation between DAS scores of the nursing students and their knowledge and attitudes regarding COVID-19 pandemic was examined, it was determined that as their anxiety levels about transmission of coronavirus increased, DAS scores also increased (p=0.037). The scores of death anxiety scale decreased as the level of students' attention to events other than coronavirus, their level of comforting themselves and their belief mentioning that they would heal if they catch coronavirus increased (p<0.05). No statistically significant correlation was found between DAS scores and other knowledge and attitudes of nursing students regarding COVID-19 pandemic (p<0.05). CONCLUSION: It would be an effective method to provide the training to nursing students, in order to change their negative attitudes and awareness towards COVID-19 related death anxiety and to improve their coping skills for death anxiety and help to reduce the burden of anxiety.

The Effect of Acupressure on Clinical Stress Management in Nursing Students: A Randomised Controlled Study.

Background: Nursing students experience clinical stress frequently and severely. The application of acupressure is reported to be effective in stress management. Objectives: This study was conducted to determine the effects of acupressure on reducing the stress of nursing students in clinical practice. Methods: This study was carried out using a single-blind randomized controlled experimental design. The experimental and control groups were randomly determined by using a previously prepared randomization checklist. A Participant Information Form, VAS, and the State Anxiety Inventory were applied to all students before practice. Acupressure was performed on the HT7 point and Yintang point (EX-HN3), respectively, every five minutes for a total of 30 minutes in the experimental group. Results: The level of stress experienced by the students in the experimental group before the intervention according to VAS was 6.95 ± 1.57, and it was determined as 2.82 ± 1.94 after the third application (p < 0.05). The mean clinical stress score before the application was 46.54 ± 3.81, and after the 3rd week of application, it was 25.15 ± 5.26 (p < 0.05). It was observed that the students' stress levels decreased in all measurements made after the acupressure intervention. Conclusion: This study determined that acupressure effectively reduces the stress levels of nursing students, and it may be applied in clinical stress management.

Atipamezole, a specific α2A antagonist, suppresses spike-and-wave discharges and alters Ca2⁺ /calmodulin-dependent protein kinase II in the thalamus of genetic absence epilepsy rats.

OBJECTIVE: The role of α2A adrenergic receptors (α2A ARs) in absence epilepsy is not well characterized. Therefore, we investigated the outcomes of the specific antagonism of α2A ARs on the spike-and-wave discharges (SWDs) in genetic absence epilepsy rats from Strasbourg (GAERSs), together with its influence on the behavior and second messenger systems, which may point to the mechanisms to which a possible SWD modulation can be related. METHODS: Atipamezole, an α2A AR antagonist, was administered intracerebroventricularly to the adult GAERSs, and electroencephalography (EEG) was conducted. The cumulative duration and number of SWDs, and the mean duration of each SWD complex were counted. The relative power of the EEG frequency bands and behavioral activity after the acute application of two doses (12 and 31 µg/5 µL) of atipamezole were evaluated. The levels of cyclic adenosine monophosphate and calcium/calmodulin-dependent kinase II (CaMKII) were measured in the cortex, thalamus, and hippocampus of naive Wistar rats and GAERSs, administered with artificial cerebrospinal fluid (aCSF) as a vehicle, or either acute or chronic atipamezole (12 µg), the latter being administered for 5 consecutive days. RESULTS: Atipamezole significantly suppressed SWDs dose-dependently, without affecting the relative power values of EEG frequency spectrum. The stereotypic activity was significantly lower in both naive Wistar rats and GAERSs receiving the highest dose (31 µg) of atipamezole compared to GAERSs receiving aCSF. In GAERSs, CaMKII levels were found to be higher in the thalamus after the acute and chronic application of SWD-suppressing doses of atipamezole (12 and 31 µg) compared to aCSF. SIGNIFICANCE: This study emphasizes the α2 AR-related modulation of absence epilepsy and particularly the significance of α2 AR antagonism in suppressing SWDs. Atipamezole's SWD-suppressive actions may be through CaMKII-mediated second messenger systems in the thalamus.

Pharmacologically induced absence seizures versus kindling in Wistar rats.

OBJECTIVE: This study aimed to investigate the effects of γ-butyrolactone (GBL), a prodrug of gamma-Hydroxybutyric acid -induced absence seizures on the development of kindling in Wistar rats. METHODS: Three groups of adult male Wistar rats under anesthesia were implanted with bilateral cortical recording electrodes for the GBL group (GBL) and/or bipolar stimulation electrodes into the right basolateral amygdala for the Kindling group (KI) alone and Kindling plus GBL group (GBL+KI). Rats in the KI and GBL+KI groups were stimulated twice daily at the afterdischarge threshold until they reached Racine's stage 5 seizure state. The animals in the GBL + group had an i.p injection of GBL 20 minutes before each electrical stimulation, and the effects of GBL-induced seizures on the development of kindling were investigated. The animals in the GBL group were injected GBL twice daily i.p. for 15 days without receiving any electrical stimulation. RESULTS: The KI animals reached stage 5 seizure stage at 12th stimulations, whereas the GBL+KI rats reached at 27th stimulations. The mean numbers of stimulations needed for the development of the first stage 3, 4, or 5 generalized seizures were significantly higher in the GBL+KI group than the KI group. CONCLUSION: The resistance to amygdala kindling in the GBL model can be modulated by the absence seizure mechanism alone, without the intervention of an abnormal genetic background.

The lower expression of parvalbumin in the primary somatosensory cortex of WAG/Rij rats may facilitate the occurrence of absence seizures.

Absence epilepsy (AE) is classified as a genetic generalized epilepsies. WAG/Rij strain of rats are regarded one of the most validated models of absence epilepsy. Studies point out the existence of hyperexcitable focus in somatosensory cortex of these rats, which has been attributed to the deficits in the GABAergic system. In the current study, we studied the changes of calcium binding proteins (CaBPs) in somatosensory cortex (S1) of the 2 and 8 month-old WAG/Rij rats and their age-matched Wistar Albino controls by investigating the expression levels of CaBPs (calbindin, calretinin and parvalbumin) in western blotting. Since WAG/Rij rats showed the low expression level of parvalbumin (PV) in western blots in comparison to Wistar Albino rats, we selectively investigated the number of PV positive neurons using the immunofluorescence staining method in order to confirm this decrement in the perioral region of somatosensory cortex (S1po). The most critical finding of this study was the age- independent reduction in the expression level of PV in the somatosensory cortex of epileptic rats as demonstrating western blotting. Nevertheless, no significant difference was found among numbers of PV + neuron in the S1po region by immunofluorescence staining concerning both of age and strain dependency. These results suggest that the disruption in the activity of the PV-expressing GABAergic interneurons might be involved in the generation of rather than the age-dependent increase in the SWDs in WAG/Rij rats.

Methodologic recommendations and possible interpretations of video-EEG recordings in immature rodents used as experimental controls: A TASK1-WG2 report of the ILAE/AES Joint Translational Task Force.

The use of immature rodents to study physiologic aspects of cortical development requires high-quality recordings electroencephalography (EEG) with simultaneous video recording (vEEG) of behavior. Normative developmental vEEG data in control animals are fundamental for the study of abnormal background activity in animal models of seizures or other neurologic disorders. Electrical recordings from immature, freely behaving rodents can be particularly difficult because of the small size of immature rodents, their thin and soft skull, interference with the recording apparatus by the dam, and other technical challenges. In this report of the TASK1 Working Group 2 (WG2) of the International League Against Epilepsy/American Epilepsy Society (ILAE/AES) Joint Translational Task Force, we provide suggestions that aim to optimize future vEEG recordings from immature rodents, as well as their interpretation. We focus on recordings from immature rodents younger than 30 days old used as experimental controls, because the quality and correct interpretation of such recordings is important when interpreting the vEEG results of animals serving as models of neurologic disorders. We discuss the technical aspects of such recordings and compare tethered versus wireless approaches. We also summarize the appearance of common artifacts and various patterns of electrical activity seen in young rodents used as controls as a function of behavioral state, age, and (where known) sex and strain. The information herein will hopefully help improve the methodology of vEEG recordings from immature rodents and may lead to results and interpretations that are more consistent across studies from different laboratories.

Exploring Nurses' Meaning and Experiences of Compassion: An International Online Survey Involving 15 Countries.

PURPOSE: In recent years, there has been much focus on compassion in nursing care, and concern has been raised in a number of reports and media stories regarding decreased compassion. The aim of this study was to explore similarities and differences in the understanding and demonstration of compassion in nursing practice across 15 countries. DESIGN: A total of 1,323 nurses from 15 countries responded to questions in relation to compassion, via an international online survey. RESULTS: The data revealed the impact of sociopolitical influences on perceptions of compassion, and the conscious and intentional nature of compassion. DISCUSSION AND CONCLUSION: The study demonstrated shared understandings of the importance of compassion as well as some common perceptions of the attributes of compassionate care. The differences reported were not as significant as had been expected. IMPLICATIONS FOR PRACTICE: Further research is needed to explore the country and culture differences in the enactment of compassion.

Job satisfaction and burnout among paediatric nurses.

PURPOSE: This study aims to determine factors of job satisfaction and burnout levels of paediatric nurses. METHODS: A total of 165 nurses working in paediatric clinics completed the Minnesota job satisfaction scale and the Maslach burnout scale. FINDINGS: Average scores of the emotional exhaustion and depersonalisation score were low, while personal accomplishment scores were high. A high level of job satisfaction, being married, increased age and a decreased number of assigned patients were significantly associated with a low level of burnout. CONCLUSIONS: Paediatric nurses experience burnout at significant levels. The most important variable that affected job satisfaction was income. IMPLICATIONS FOR NURSING PRACTICE: The results of the study could guide development of strategies that might prevent or alleviate burnout of paediatric nurses.

Natural Killer-Like T-Cell Lymphoma Localized to the Terminal Ileum: Case Report.

Intestinal intraepithelial lymphocytes are non-organized lymphoid populations that are composed of heterogeneous subsets with diverse ontogeny and phenotypes, and the differential diagnosis is crucial. A 43-year-old male patient underwent an emergency laparotomy due to a perforated mass of the terminal ileum. A right hemicolectomy plus small bowel resection was performed. Histopathological examination showed medium to large cells with vesicular nuclei, including marked nucleoli with large, colorless cytoplasm. No signs of celiac disease were found in the adjacent mucosa. The tumor cells were immunohistochemically CD45+, CD3+, CD4+, CD8+, CD56+, Pan-Cytokeratin-, CD20-, CD79a-, CD5- and CD30-. Endomysial antibody and antigliadin antibody, IgM and IgG tests; and anti-Ebstein Barr virus latent membrane protein all proved negative. Finally, the histopathological diagnosis of tumor mass was natural killer-like T-cell lymphoma. Primary intestinal cytotoxic natural killer-like T-cell lymphoma is a rare entity, which is difficult to distinguish from other T-cell lymphomas. In addition to microscopic evaluation, immunohistochemical analysis and serological tests are essential to reach a definitive diagnosis.

Evaluation of GAD67 immunoreactivity in the region of substantia nigra pars reticulata in resistance to development of convulsive seizure in genetic absence epilepsy rats.

OBJECTIVE: Nonconvulsive absence epilepsy and convulsive epilepsy seizures are rarely seen in the same patient. It has been demonstrated that there is a resistance to development of convulsive seizures in genetic absence epilepsy models. The present study investigated glutamic acid decarboxylase (GAD) immunoreactivity in the brain region related to the interaction of these two seizure types, namely substantia nigra pars reticulata (SNR) subregions, SNRanterior and SNRposterior. METHODS: Nonepileptic adult male Wistar rats and Genetic Absence Epilepsy Rats from Strasbourg (GAERS) were used. Experimental groups of Wistar and GAERS were electrically stimulated for kindling model to induce convulsive epileptic seizures. An electrical stimulation cannula was stereotaxically implanted to the basolateral amygdala and recording electrodes were placed on the cortex. Sagittal sections of SNR were used to evaluate immunohistochemical reaction. Sections were incubated with anti-GAD67 antibody. Densitometric analysis of GAD67 immunoreactive neurons was performed using photographs of stained sections. One-way analysis of variance and post hoc Bonferroni test were used for statistical analysis of the data. RESULTS: There was no difference in GAD67 immunoreactivity of SNR subregions of control Wistar and control GAERS. An increase in GAD67 immunoreactivity was detected in SNRposterior subregion of stimulated Wistar rats, whereas there was a decrease in GAD67 immunoreactivity in SNRposterior of stimulated GAERS. The difference in GAD67 immunoreactivity between these two groups was statistically significant. CONCLUSION: Level of synthetized gamma-aminobutyric acid in SNRposterior subregion plays an important role in the interaction of nonconvulsive absence epilepsy seizures and convulsive epilepsy seizures.

The role of the substantia nigra pars reticulata in kindling resistance in rats with genetic absence epilepsy.

OBJECTIVE: Genetic Absence Epilepsy Rats from Strasbourg (GAERS) show a resistance to secondary generalization of focal limbic seizures evoked by kindling. The substantia nigra pars reticulata (SNR) is involved in the propagation and modulation of seizures in kindling. We first examined the role of the SNRanterior and SNRposterior subregions in the resistance to the development of kindling in GAERS. Subsequently, to determine whether kindling resistance relates to differential sensitivity of γ-aminobutyric acid γ-aminobutyric acid (GABA)ergic or dopaminergic SNR neurons to kindling, we studied the effects of kindling-inducing stimulations on parvalbumin (PRV; GABAergic neuron marker) or tyrosine hydroxylase (TH; dopaminergic neuron marker) immunoreactivity (ir), respectively, in GAERS and in nonepileptic control (NEC) Wistar rats that lack kindling resistance. METHODS: Adult male GAERS were implanted with a stimulation electrode in the amygdala, and bilateral injection cannulas for lidocaine or saline injection (30 min before each kindling stimulation until the animals reached three stage 5 seizures or the 22 stimulations) into the SNRanterior or SNRposterior . In another experiment, PRV-ir in SNRanterior and SNRposterior and TH-ir in SNRposterior only were densitometrically compared in GAERS-SHAM, NEC-SHAM GAERS-STIM, and NEC-STIM animals (6 kindling stimulations). RESULTS: Bilateral SNRposterior infusions of lidocaine eliminated the kindling resistance and resulted in stage 5 generalized motor seizures in all kindled rats. Bilateral lidocaine infusions in the SNRanterior failed to alter the kindling resistance in GAERS. PRV-ir in the SNRposterior was unaltered in GAERS-STIM but increased in NEC-STIM group. Cellular TH-ir in the SNRposterior significantly increased by kindling stimulations in both NEC-STIM and GAERS-STIM groups. SIGNIFICANCE: The kindling resistance in GAERS is mediated by the SNRposterior in a lidocaine-sensitive manner. The insensitivity to kindling stimulation of PRV-ir in SNRposterior of GAERS but not NEC rats, implicate GABAergic SNRposterior neurons in kindling resistance. In contrast, the observed stimulation-specific increase in TH-ir in the SNRposterior is unrelated to kindling resistance.