Antoinette Conca, Doaa Ebrahim, Sandra Noack, Angela Gabele, Helen Weber, Mehrnaz Prins, Anja Keller, Mariann Hari, Angela Engel, Katharina Regez, Ursula Schild, Philipp Schuetz, Beat Müller, Sebastian Haubitz, Alexander Kutz, Andreas Huber, Lukas Faessler and Petra Schäfer-Keller
crossing over of clusters at different time points (for example, switching from control to intervention in a random rollout). The baseline is the first time point of measurement where no intervention is received. At subsequent time points, the clusters start the planned intervention and the response to the intervention are continuously measured ( figure 1 ).
Ward-level randomization in stepped wedge clusters in weeks
The time for a cluster to begin the intervention is randomized ( Hussey & Hughes, 2007 ). The design is considered suitable for the
Effects of Ketamine on Memory and Nociception in Rats
Background: Ketamine is intravenous anaesthetic with NMDA-glutamate receptors mechanism of action.
Material and methods: Male Wistar rats were treated with saline (group A) or 10, 15 or 20 mg/kg of ketamine (groups B, C and D, respectively). For active avoidance test an automatic reflex conditioner was used. The observed variables were number of avoidances, escapes and intertrial crossings. Step-through and step-down passive avoidance tests were done with learning and memory retention test. Criteria for step-through test were latency of reactions of 180 sec in the light chamber. Criteria for step-down test were latency of reaction of 60 sec on the platform. The hot-plate test evaluates the reaction time of the rats dropped on a heated surface. The analgesy-meter test exerts a force increased at constant rate.
Results: In active avoidance test the controls increased the number of avoidances during learning and memory tests. Ketamine in all doses used increased the number of avoidances during learning and in memory test. Controls did not change the number of escapes, but the ketamine treated animals decreased it. The number of intertrial crossings was not changed by controls or ketamine-treated rats during learning and memory tests. In passive avoidance tests the controls and ketamine-treated rats increased the latency time during learning and memory retention tests. In hot-plate analgesic test and in analgesy-meter test the controls and ketamine-treated rats did not change the latency of reaction.
Conclusion: The results suggest that ketamine improves learning and memory processes and has no analgesic effect in the doses applied.
Maria T. Georgieva-Kotetarova and Ivanka I. Kostadinova
During the past decade, evidence has emerged that statins have neuroprotective effects.
AIM: The aim of this study was to investigate the effects of atorvastatin and rosuvastatin on learning and memory in rats with diazepam-induced amnesia.
MATERIAL AND METHODS: Experiments were carried out on 48 white male Wistar rats, divided into 6 groups, each of 8 rats. The experimental animals were treated per os for 14 days with atorvastatin and rosuvastatin in doses of 10 mg/kg and 20 mg/kg body weight, respectively. To induce amnesia diazepam was administered intraperitoneally in a dose of 2.5 mg/kg bw. Cognitive skills of the animals were examined after the induction of amnesia with active avoidance test using autonomic reflex conditioner (shuttle box) and passive avoidance tests (step-through and step down) (Ugo Basile, Italy). The following parameters were assessed: number of conditioned responses (avoidances), number of unconditioned responses (escapes) and number of intertrial crossings in the active avoidance test; latency of reactions was measured in the passive avoidance tests.
RESULTS: We found a significant increase of conditioned responses in atorvastatin treated animals (in a dose of 10 mg/kg bw) in active avoidance training. In the animals treated with rosuvastatin in both doses there was a statistically significant increase of unconditioned responses. In the step-through passive avoidance test there was significant improvement of short-term and long-term memory following administration of atorvastatin (10 mg/kg bw). Rosuvastatin (10 mg/kg bw) preserves long-term memory. In the step-down passive avoidance test, atorvastatin (10 mg/kg bw) and rosuvastatin (10 mg/kg bw and 20 mg/kg bw) preserve long-term memory.
CONCLUSIONS: Atorvastatin (10 mg/kg bw) and rosuvastatin (10 mg/kg and 20 mg/kg bw) improve cognitive functions in rats with diazepam-induced amnesia and preserve longterm memory.
Gina Amanda, Dianiati Kusumo Sutoyo and Erlina Burhan
( 7 , 8 , 9 ). Pneumococci are 0.5–1.25 mm in diameter, non-motile, and do not form spores. Their best growth requires 5% of carbon dioxide and needs catalase to neutralize a large number of hydrogen peroxides which are produced by bacteria. On blood agar, pneumococci are shown as glisten colonies and form a zone of alpha-haemolysis that has a greenish colour. This zone differentiates pneumococci with beta-haemolytic bacteria, but it is also found in commensal streptococci such as Streptococcus viridans Optochin and bile solubility test may be performed to
were recorded as lasting 121 s [ 5 , 7 ]. The adhesive sticker removal task was evaluated at 1 day before injury (day 1) and postinjury on days 3, 7, 14, 21, 28, and 35.
Horizontal ladder test
A horizontal ladder test was used to assess skilled locomotion. The horizontal wooden ladder used was 129.39 cm long and 16.51 cm wide, and 37 rungs (0.79 cm diameter) were inserted 2.5, 3.2, or 5.7 cm apart [ 3 ]. While rats crossing the ladder, was focused behavior on the side of the injury. The pattern of rungs was changed weekly to prevent animals from learning and
Maria T. Georgieva-Kotetarova, Ivanka I. Kostadinova and Delian P. Delev
Statins are widely used for treatment of hyperlipidemia. They have been shown to possess pleiotropic effects apart from their lipid-lowering activity - anti-inflammatory, immunomodulatory, and neuroprotective. Most studies suggest that statins can protect the brain against damage but it is not clear whether they improve cognitive function in patients without neuropathy. The aim of the present study was to investigate the effect of 3-month treatment with atorvastatin and rosuvastatin on learning and memory processes in rats without brain damage. Wistar rats were treated orally for 90 days with atorvastatin and rosuvastatin at a dose of 10 mg/kg b. w. in parallel with the vehicle-treated group. After that period, learning ability and memory retention was evaluated using an active avoidance test - automatic reflex conditioner (shuttle box). The learning session was carried out on 5 consecutive days. Memory retention test was performed on day 12. The following behavioral reactions were investigated: conditioned responses (avoidance), unconditioned responses (escapes), and intertrial crossings. We found increased number of conditioned responses in groups, treated with atorvastatin 10 mg/kg b.w., and with rosuvastatin 10 mg/kg b.w. during the learning session and on the memory retention test, as compared to the same-day control group. The atorvastatin-treated group showed an increased number of unconditioned responses on days 1 and 2, as compared to the control group. In the group treated with Rosuvastatin there was an increased number of escapes on days 1,2 and 4, as compared to the vehicle-treated group. Atorvastatin and rosuvastatin at a dose of 10 mg/kg b.w. improved processes of learning and memory retention after the 3-month treatment.
vertical line. The parotid artery perforator deviates because there were 4 branches running across the lateral canthal line at the lower alar level in 4 of 7 specimens. There were 2 facial artery perforators crossing the lateral canthal line between the lower eye lid and tip of the nose level. The diameter of the buccal branch shows a significant sex difference ( P = 0.018), the buccal branch diameter in men was larger than in women. However, the buccal artery perforator diameter in men was significantly larger than it was in women ( P = 0.019). Table 2 shows the
Ingfar Soontarawirat, Mallika Imwong, Charles J. Woodrow, Chalisa Louicharoen Cheepsunthorn, Nicholas P.J. Day, Richard Paul and Pratap Singhasivanon
). These abnormalities are because of complex mutations in opsin genes on the Xq28 chromosome coding for the long-wavelength and middle-wavelength sensitive cone photopigments ( OPN1LW and OPN1MW respectively) [ 9 ].
The telomeric region of the X chromosome within band Xq28 consists of about 3 Mb and contains the genes coding for G6PD, the opsin red or green color pigments, and coagulation factor VIIIc. The distance between the opsin genes and G6PD is approximately 300 kb [ 10 , 11 ]. Consistent with the strong linkage disequilibrium between the genes, a number
Effat Hatefnia, Kobra Alizadeh and Mostafa Ghorbani
Hypertension is one of the most important risk factors for atherosclerosis, cerebrovascular accident, and heart and renal failure in many countries, and the leading cause of preventable premature deaths worldwide [ 1 , 2 ]. Hypertension refers to intermittent and continuous increase of blood pressure in an individual through which his or her systolic blood pressure might continuously be ≥140 mm Hg and diastolic blood pressure might be ≥90 mm Hg [ 3 ]. Hypertension itself accounts for 7 million premature deaths worldwide [ 4 ]. The number of people suffering