Integrating EEG and Machine Learning to Analyze Brain Changes during the Rehabilitation of Broca's Aphasia.

The fusion of electroencephalography (EEG) with machine learning is transforming rehabilitation. Our study introduces a neural network model proficient in distinguishing pre- and post-rehabilitation states in patients with Broca's aphasia, based on brain connectivity metrics derived from EEG recordings during verbal and spatial working memory tasks. The Granger causality (GC), phase-locking value (PLV), weighted phase-lag index (wPLI), mutual information (MI), and complex Pearson correlation coefficient (CPCC) across the delta, theta, and low- and high-gamma bands were used (excluding GC, which spanned the entire frequency spectrum). Across eight participants, employing leave-one-out validation for each, we evaluated the intersubject prediction accuracy across all connectivity methods and frequency bands. GC, MI theta, and PLV low-gamma emerged as the top performers, achieving 89.4%, 85.8%, and 82.7% accuracy in classifying verbal working memory task data. Intriguingly, measures designed to eliminate volume conduction exhibited the poorest performance in predicting rehabilitation-induced brain changes. This observation, coupled with variations in model performance across frequency bands, implies that different connectivity measures capture distinct brain processes involved in rehabilitation. The results of this paper contribute to current knowledge by presenting a clear strategy of utilizing limited data to achieve valid and meaningful results of machine learning on post-stroke rehabilitation EEG data, and they show that the differences in classification accuracy likely reflect distinct brain processes underlying rehabilitation after stroke.

Increased pituitary adenylate cyclase-activating peptide genes expression in the prefrontal cortex in schizophrenia in relation to suicide.

Introduction: Pituitary adenylate cyclase-activating peptide (PACAP) is a stress-related neuropeptide that is produced in several brain areas. It acts by 3 receptors: PACAP type-1 (PAC1), vasoactive intestinal peptide (VIP) -1 and -2 (VPAC1 and 2). Data on polymorphisms in PACAP and PAC1 indicate a relationship of the PACAP system with schizophrenia (SCZ). Methods: The prefrontal cortex was chosen to measure PACAP-gene related expression changes, since this is a central structure in the symptoms of schizophrenia (SCZ). We investigated alterations in the expression of the PACAP-related genes by qPCR in the human dorsolateral prefrontal cortex (DLPFC) and anterior cingulate cortex (ACC) of 35 SCZ patients and 34 matched controls in relation to SCZ, suicide, gender and medication. Results: The ACC revealed an upregulation in PACAP, PAC1, VPAC1 and VPAC2 in SCZ suicide (S) completers compared to controls. An increase in PACAP, VPAC1 and VPAC2 expression was also present in the ACC in SCZ-S compared to SCZ patients who died naturally (SCZ-N). In the DLPFC, an increase in PAC1 was found in SCZ-N patients compared to SCZ-S and controls. Moreover, an increase in all PACAP-related genes was present in SCZ-N male patients compared to SCZ-N females. Concluding, expression changes were found in PACAP-related genes in relation to SCZ, suicide and gender. In particular, there was a higher PACAP-related gene expression in SCZ patients in the ACC in relation to suicide and in DLPFC in relation to SCZ. Discussion: These findings suggest a potential link between PACAP and the pathophysiology of SCZ and suicide. Further research is needed to understand the functional significance and potential clinical applications of these changes.

Hypoplastic arteries of the cerebral arterial ring in the blind spot of computed tomography angiography.

BACKGROUND: Some variations of the cerebral arterial circle (CAC) are associated with an increased risk for the development of various pathological conditions. This paper aimed to determine the prevalence of hypoplastic arteries of CAC and to emphasize the limited possibility of their visualization by computed tomography angiography (CTA). MATERIALS AND METHODS: The research was performed on 400 adult cadavers by macro- and microdissection of the cerebral arteries. Each case was photographed and the diameter of the arteries was measured digitally, by analyzing photographs of the bases of the brain in the ImageJ program. RESULTS: The largest prevalence of artery diameter <1mm (<0.6mm) in CAC had the posterior communicating artery (PCoA). PCoA on the left side was hypoplastic in 44.9% (11.4%) of cases, while the same artery on the right side was hypoplastic in 44.3% (6.6%) of cases. The posterior cerebral artery was hypoplastic on the left side in 3% (0.6%) and on the right side in 4.2% (0.6%) of cases. The anterior cerebral artery had a hypoplastic caliber only on the right side in 2.4% (0.6%) of the cases, while the internal carotid arteries did not have a diameter <1mm in any case. The anterior communicating artery showed the greatest variability in morphology. Studies on CTA describe the occurrence of aplasia in a statistically significantly higher percentage, and the occurrence of hypoplastic arteries in a statistically significantly lower percentage compared to studies on cadavers. CONCLUSIONS: Due to significant differences between cadaveric and radiological studies, it is necessary to analyze their results regarding arterial hypoplasia and aplasia separately. A diameter of less than 1 mm has been suggested as a criterion for arterial hypoplasia.

Marital status and survival in cancer patients: A systematic review and meta-analysis.

BACKGROUND: In recent years, authors have repeatedly reported on the significance of social support in cancer survival. Although overall the studies appear to be convincing, little is known about which types of social support promote better survival rates, and which subgroups of cancer patients are more susceptible to the benefits of it. The aim of this study was to identify, organize, and examine studies reporting on the significance of social support in cancer survival. METHODS: The PubMed, CINAHL and EBSCO databases were searched using the keywords social support/marital status, cancer, and survival/mortality. Where possible we used a meta-analytical approach, specifically a random effect model, in order to combine the results of the hazard ratios in studies from which this information could be obtained. When interpreting clinical relevance, we used the number needed to treat (NNT). RESULTS: Better survival was observed in married patients when compared to unmarried (single, never-married, divorced/separated, and widowed) in overall and cancer-specific survival. Gender group differences showed that the association was statistically significant only in cancer-specific survival when comparing divorced/separated male and female cancer patients (p < 0.001), thus confirming results from the previous meta-analysis. CONCLUSIONS: Being unmarried is associated with significantly worse overall and cancer-specific survival. The most vulnerable group found in our study were divorced/separated men. The results of this review can motivate physicians, oncologists, and other healthcare professionals to be aware of the importance of patients' social support, especially in the identified sub-group.

Olanzapine decreased osteocyte maturation and Wnt/ß-catenin signaling during loading of the alveolar bone in rats.

Several studies indicate the influence of olanzapine on bone metabolism; however, the results are contradictory. We evaluated the effects of olanzapine on the Wnt/ß-catenin signaling pathway, physiological alveolar bone turnover, and alveolar bone modeling due to an applied orthodontic force. Adult male rats (n=48) were treated with either olanzapine or a vehicle for 21 days; then 8 rats from each group were sacrificed and the rest were divided into 4 groups: control, appliance-only, olanzapine-only, and olanzapine-appliance. The rats in the appliance groups were mounted with a superelastic closed coil spring that maintained constant orthodontic force between molars and incisors. We studied the effects of olanzapine on physiological alveolar bone turnover on day 21 of the experiment, and on alveolar bone modeling due to orthodontic force on day 56. We determined tooth movement, alveolar bone volume, activity of bone-specific cells, serum alkaline phosphatase (ALP) activity, and gene expression levels of Wnt/ß-catenin signaling target genes. During forced bone modeling, olanzapine increased osteoblast volume (P<0.0001) and ALP activity (P=0.0011) and decreased osteoclast volume (P<0.0001) and gene expression of the Wnt/ß-catenin signaling target genes Fosl1, Axin2, and Dkk1(P=0.001, P=0.0076, and P=0.036, respectively), and the osteocyte markers Sost and Dmp1 (P=0.0432 and P=0.0021, respectively). Similar results were obtained during physiological alveolar bone turnover on day 21, when olanzapine downregulated the gene expression of osteocyte markers and Wnt/ß-catenin signaling target genes. We concluded that olanzapine attenuated osteocyte maturation during forced bone modeling and physiological alveolar bone turnover, potentially through downregulation of the Wnt/ß-catenin signaling pathway.

Neural Bases of Age-Related Sensorimotor Slowing in the Upper and Lower Limbs.

With advanced age, there is a loss of reaction speed that may contribute to an increased risk of tripping and falling. Avoiding falls and injuries requires awareness of the threat, followed by selection and execution of the appropriate motor response. Using event-related potentials (ERPs) and a simple visual reaction task (RT), the goal of our study was to distinguish sensory and motor processing in the upper- and lower-limbs while attempting to uncover the main cause of age-related behavioral slowing. Strength (amplitudes) as well as timing and speed (latencies) of various stages of stimulus- and motor-related processing were analyzed in 48 healthy individuals (young adults, n = 24, mean age = 34 years; older adults, n = 24, mean age = 67 years). The behavioral results showed a significant age-related slowing, where the younger compared to older adults exhibited shorter RTs for the upper- (222 vs. 255 ms; p = 0.006, respectively) and the lower limb (257 vs. 274 ms; p = 0.048, respectively) as well as lower variability in both modalities (p = 0.001). Using ERP indices, age-related slowing of visual stimulus processing was characterized by overall larger amplitudes with delayed latencies of endogenous potentials in older compared with younger adults. While no differences were found in the P1 component, the later components of recorded potentials for visual stimuli processing were most affected by age. This was characterized by increased N1 and P2 amplitudes and delayed P2 latencies in both upper and lower extremities. The analysis of motor-related cortical potentials (MRCPs) revealed stronger MRCP amplitude for upper- and a non-significant trend for lower limbs in older adults. The MRCP amplitude was smaller and peaked closer to the actual motor response for the upper- than for the lower limb in both age groups. There were longer MRCP onset latencies for lower- compared to upper-limb in younger adults, and a non-significant trend was seen in older adults. Multiple regression analyses showed that the onset of the MRCP peak consistently predicted reaction time across both age groups and limbs tested. However, MRCP rise time and P2 latency were also significant predictors of simple reaction time, but only in older adults and only for the upper limbs. Our study suggests that motor cortical processes contribute most strongly to the slowing of simple reaction time in advanced age. However, late-stage cortical processing related to sensory stimuli also appears to play a role in upper limb responses in the elderly. This process most likely reflects less efficient recruitment of neuronal resources required for the upper and lower extremity response task in older adults.

Nutrition and Congruent Care Improve Wellbeing of Residents With Dementia in Slovenian Care Homes.

Introduction: Current nutritional strategies for people with dementia focus on nutritional diets and regimens, although in recent years congruent care for people with dementia has been increasingly recognized to improve their wellbeing. This includes consistency of care, respecting the variability of psycho-sociological factors, emphasizing the importance of participation in activities, and congruence with the individual's needs and capabilities. When applied to the nutritional aspects of care, it aims to empower people with dementia to have an active role in their care and during meals. Congruent care has previously shown promising results in improving the quality of life of residents, reducing the incidence of negative social interactions and daily intake of medicines. Methods: A mixed methods qualitative-quantitative study was carried out. Out of 102 residential care homes for the elderly in Slovenia, a non-random sample of homes was selected. Seven homes that have implemented congruent care and five who have not implemented it agreed to participate. Content analysis of the transcripts of focus group interviews was carried out, to establish how the congruent care model was included into their everyday practice of care for people with dementia. Qualitative comparative analysis was used to describe the differences in the practice of care between the two groups of homes, in the fields of nutritional and general care. Frequencies and assigned importance of statements relating to different aspects of nutritional care were statistically compared. Results: The introduction of congruent care improved the wellbeing of the people with dementia, as observed by caregivers. The homes that had implemented congruent care gave more attention to the food choice aspects of nutritional care (p = 0.0474, 95%CICongruent = 50.77-72.35%, 95%CINon-congruent = 27.65-49.23%), while the homes that had not were more attentive to the dietary intake aspects (p = 0.0067, 95%CICongruent = 22.79-44.74%, 95%CINon-congruent = 55.26-77.21%). In the homes for the elderly that had implemented congruent care, both caregivers and management reported that the frequency of use of pro re nata medication decreased, which is supported by the results of the linear regression ( R 2 adjusted =78.4, p = 0.005), although the data available is limited. Conclusion: First, the people with dementia in the care homes that had implemented congruent care were observed to have improved in mood, attitudes toward eating and wellbeing, as reported by caregivers. Second, the implementation of congruent care was well received by the management and caregivers of the care homes. A model of implementation of congruent nutritional care for people with dementia is presented.

Assessment of Model Accuracy in Eyes Open and Closed EEG Data: Effect of Data Pre-Processing and Validation Methods.

Eyes open and eyes closed data is often used to validate novel human brain activity classification methods. The cross-validation of models trained on minimally preprocessed data is frequently utilized, regardless of electroencephalography data comprised of data resulting from muscle activity and environmental noise, affecting classification accuracy. Moreover, electroencephalography data of a single subject is often divided into smaller parts, due to limited availability of large datasets. The most frequently used method for model validation is cross-validation, even though the results may be affected by overfitting to the specifics of brain activity of limited subjects. To test the effects of preprocessing and classifier validation on classification accuracy, we tested fourteen classification algorithms implemented in WEKA and MATLAB, tested on comprehensively and simply preprocessed electroencephalography data. Hold-out and cross-validation were used to compare the classification accuracy of eyes open and closed data. The data of 50 subjects, with four minutes of data with eyes closed and open each was used. The algorithms trained on simply preprocessed data were superior to the ones trained on comprehensively preprocessed data in cross-validation testing. The reverse was true when hold-out accuracy was examined. Significant increases in hold-out accuracy were observed if the data of different subjects was not strictly separated between the test and training datasets, showing the presence of overfitting. The results show that comprehensive data preprocessing can be advantageous for subject invariant classification, while higher subject-specific accuracy can be attained with simple preprocessing. Researchers should thus state the final intended use of their classifier.

Real-life dental examination elicits physiological responses different to visual and auditory dental-related stimuli.

BACKGROUND: Previous studies on dental anxiety have examined the psychophysiological responses evoked in dentally anxious subjects by dental-related stimuli, but not during a real-life dental examination, which was achieved in the present study. METHODS: The heart rate, skin conductance level, and heart rate variability of 25 subjects with dental anxiety and 25 healthy controls were examined. Anxiety was determined by the Modified Dental Anxiety Scale and the Dental Anxiety Scale-Revised. The psychophysiological reactions of the two groups were compared during exposure to dental-related pictures, dental-related sounds, and an actual examination in a dental surgery. RESULTS: All the dental-related stimuli provoked an increase in heart rate, i.e. visual stimuli (p<0.001; 95% CI 0.98-3.95 bpm), auditory stimuli (p<0.001; 95% CI 1.34-4.99 bpm), and a dental examination (p<0.001; 95% CI 1.26-5.39 bpm). Dental-related pictures provoked inferior skin conductance level changes compared to dental-related sounds and the dental examination (visual modality vs auditory p<0.001; 95% CI 0.039-0.152; visual modality vs examination p<0.001; 95% CI 0.083-0.275). Heart rate variability manifested in a complex pattern of responses to the dental examination. However, when exposed to all three dental-related stimuli presentation conditions, the heart rate (F = 0.352, p = 0.556), skin conductance level (F = 0.009, p = 0.926), and heart rate variability parameters of subjects with dental anxiety did not differ in comparison to the healthy controls. CONCLUSIONS: This pilot study represents an evaluation of psychophysiological reactions during a real-life dental examination compared to single modality stimuli, and shows that a real-life dental examination provokes an increase in heart rate, heart rate variability and skin conductance level. Additionally, autonomic responses did not differ between the experimental and control groups. The key issue for future studies is the effect of real-life situations on the physiological and psychological state of the subjects, which should be considered when planning new research and studied in depth.

Mental health and drug use severity: the role of substance P, neuropeptide Y, self-reported childhood history of trauma, parental bonding and current resiliency.

BACKGROUND: Many risk factors lead to opioid use and drug-related problems. One of the challenges to understand behavioural factors, drug problems and psychopathology is to identify biological markers that are suitable for research on broad substance abuse and dependence involving human participants. AIMS: The study has examined the relationships between the self-reported childhood history of trauma, parental bonding, psychopathology, impulsivity, current resiliency, two neuropeptides, possible markers of behaviour and emotion regulation, and severity of drug-related problems. METHODS: One hundred and sixty-seven individuals with a history of opioid use completed questionnaires. Serum neuropeptide Y (NPY) and substance P (SP) levels were analysed. Moderating and mediating relationships between variables were examined using structural equation modelling (SEM). RESULTS: Antisocial features, depression, impulsivity, SP, NPY, emotional neglect and resilience are associated with severity of drug-related problems. SP is associated with antisocial personality traits. CONCLUSIONS: The novelty of this study is the proposed possible link between biochemical markers, antisocial features and behavioural and emotional regulation. Serum NPY and SP levels have a potential to be used as a biomarker in opioid users before and in the treatment process to account for interactions between biological vulnerabilities and childhood risk factors in predicting behavioural adjustment and more severe drug-related problems.

Increased Risk-Taking Behaviour and Brain-Derived Neurotrophic Factor Val66Met Polymorphism Correlates to Decreased Serum Brain-Derived Neurotrophic Factor Level in Heroin Users.

BACKGROUND: This study has examined the relationships and interactions between serum brain-derived neurotrophic factor (BDNF) levels, BDNF Val66Met polymorphism and self-reported risk-taking behaviour in individuals with a history of heroin use undergoing outpatient treatment in comparison to healthy individuals. METHODS: We enrolled 167 heroin users and 86 healthy subjects and examined serum BDNF levels, Val66Met polymorphism, and personal characteristics using Connor Davidson Resilience Scale, Risk-taking (RT) propensity questionnaire, and Personality Assessment Inventory. RESULTS: Heroin users had significantly higher serum BDNF levels than controls. In addition, serum BDNF levels were significantly higher in Val/Val carriers than in Met/Val or Met/Met in all recruited subjects. Furthermore, a stepwise multiple regression analysis of serum BDNF levels as a dependent variable with related factors showed that in heroin users, Alcohol Use Disorder Identification Test score, anxiety and RT score were found as independent contributors to serum BDNF levels. When performing gene-environment interaction it was additionally found that heroin users with self-reported high risk-taking behaviour had significantly lower levels of serum BDNF among heroin users with the Met allele. CONCLUSIONS: These results indicate that genetic variant Met66 decreased the serum BDNF levels in combination with self-reported risk-taking propensity among heroin users. If results of future work confirm the influence of this combined effect between neurotrophic genotype and risk-taking behaviour, 66Met carriers might require higher levels of intervention to overcome their drug use pattern and risky behaviour.

Sub-therapeutic doses of fluvastatin and valsartan are more effective than therapeutic doses in providing beneficial cardiovascular pleiotropic effects in rats: A proof of concept study.

BACKGROUND: Statins and sartans can, in therapeutic doses, induce pleiotropic cardiovascular effects. Similar has recently been shown also for sub-therapeutic doses. We thus explored and compared the cardiovascular pleiotropic efficacy of sub-therapeutic vs. therapeutic doses. METHODS: Wistar rats were randomly divided into 7 groups receiving fluvastatin, valsartan and their combination in sub-therapeutic and therapeutic doses, or saline. After 6weeks, the animals were euthanised, their hearts and thoracic aortas isolated, and blood samples taken. Endothelium-dependent relaxation of the thoracic aortae and ischaemic-reperfusion injury of the isolated hearts were assessed along with the related serum parameters and genes expression. RESULTS: Fluvastatin and valsartan alone or in combination were significantly more effective in sub-therapeutic than therapeutic doses. The sub-therapeutic combination greatly increased thoracic aorta endothelium-dependent relaxation and maximally protected the isolated hearts against ischaemia-reperfusion injury and was thus most effective. Beneficial effects were accompanied by increased levels of nitric oxide (NO) and decreased levels of asymmetric dimethylarginine (ADMA) in the serum (again prominently induced by the sub-therapeutic combination). Furthermore, nitric oxide synthase 3 (NOS3) and endothelin receptor type A (EDNRA) genes expression increased, but only in both combination groups and without significant differences between them. In the therapeutic dose groups, fluvastatin and valsartan decreased cholesterol values and systolic blood pressure. CONCLUSION: Sub-therapeutic doses of fluvastatin and valsartan are more effective in expressing cardiovascular pleiotropic effects than therapeutic doses of fluvastatin and/or valsartan. These results could be of significant clinical relevance.

Cardioprotective effects of silver fir (Abies alba) extract in ischemic-reperfused isolated rat hearts.

BACKGROUND: Silver fir trunk extract (SFTE) is a complex mixture of antioxidative polyphenols (lignans and phenolic acids) from the trunks of silver fir trees (Abies alba, lignum). In our previous study, we have shown that SFTE exerts strong antioxidative and protective effects against atherogenic, diet-induced arterial wall damage. OBJECTIVE: The aim of the present study was to test the potential protective effects of SFTE and its compounds, two phenolic acids (p-coumaric and protocatechuic acids) in ischemia-reperfusion injury of isolated rat hearts. DESIGN: Isolated hearts of Wistar rats aged 4-8 weeks were exposed to perfusion, ischemia, and reperfusion periods. The experiments were performed using the following five groups: control, SFTE (10 µg/L), SFTE (100 µg/L), protocatechuic acid, and p-coumaric. Aortas were isolated to measure vascular responses in the presence of Nω-Nitro-L-arginine. RESULTS: SFTE dose-dependently reduced ischemic-reperfusion heart damage, which was indicated as the decrease in the lactate dehydrogenase (LDH) release rate and arrhythmias duration by 80% and an increase in coronary flow rate during the reperfusion period. Two tested compounds (p-coumaric and protocatechuic acids) acted less cardioprotective, since they decreased the duration of arrhythmias only by 40 and 45%, respectively, and did not decrease LDH release rates during the reperfusion period. Only p-coumaric acid increased coronary flow rates, whereas protocatechuic acid did not. CONCLUSIONS: We conclude that the SFTE exerted the strongest cardioprotective effect, whereas its constituents (the p-coumaric and protocatechuic acids) were less effective in inducing cardioprotection.

The "Rise-Peak-Fall" Pattern of Time Dependency of the Cardiovascular Pleiotropic Effects of Treatment With Low-dose Atorvastatin, Losartan, and a Combination Thereof in Rats.

Treatment with low, subtherapeutic doses of statins and sartans expresses beneficial pleiotropic effects on the arterial wall. The present study explored whether these effects depend on treatment duration. Wistar rats were randomly divided into 4 groups and received low-dose atorvastatin, low-dose losartan, their combination, or saline (control) daily. After 4, 6, 8, and 10 weeks of treatment, the animals were anesthetized, blood samples taken, and hearts and thoracic aortas isolated. Thoracic aorta endothelium-dependent relaxation and parameters of the isolated heart exposed to ischemic-reperfusion injury were assessed along with blood serum parameters and vasoactive genes expression. Low-dose atorvastatin, losartan, and especially their combination showed the characteristic time dependency of all studied parameters (thoracic aorta relaxation, isolated heart parameters, C-reactive protein values, genes encoding endothelial nitric oxide synthase, and CD40). The peak in efficacy was observed after 6 weeks of treatment and subsequently steadily declined. The peak versus control values were significant for all measured parameters. Only a combination of atorvastatin and losartan increased nitric oxide and decreased asymmetric dimethylarginine. A characteristic time-dependent "rise-peak-fall" pattern of the cardiovascular pleiotropic effects of statins and sartans in subtherapeutic low doses was revealed. Evidently, resistance to the explored treatment occurs after a certain period.

Bone remodeling during orthodontic tooth movement in rats with type 2 diabetes.

INTRODUCTION: Type 2 diabetes is known to affect bone metabolism. In this study, we aimed to determine the effects of type 2 diabetes on bone remodeling during orthodontic tooth movement. METHODS: The 48 rats were divided into 4 groups: Wistar control group (n = 8), Goto-Kakizaki (GK) control group (n = 8), Wistar appliance group (n = 16), and GK appliance group (n = 16). The distances between the teeth were measured weekly. On day 42, maxillary alveolar bone specimens were obtained for histologic evaluation and determination of the gene expression levels of the receptor activator of nuclear factor Ò¡B (RANK), RANK ligand (RANKL), and osteoprotegerin (OPG). RESULTS: No significant difference was observed in the levels of tooth movement between the 2 appliance groups. After orthodontic force application, the alveolar bone volume and osteoblast surface in the GK rats were diminished compared with those in the Wistar rats. The increase in the osteoclast surface relative to the control groups was 2.4-fold greater in the GK rats than in the Wistar rats. Significant upregulations of the RANK and OPG gene expression levels in the Wistar appliance group were observed. The RANKL/OPG ratio was increased in the GK appliance group compared with the Wistar appliance group. CONCLUSIONS: Diminished bone formation and slightly increased bone resorption were observed during orthodontic tooth movement in the rats with type 2 diabetes.

Silver fir (Abies alba) trunk extract protects guinea pig arteries from impaired functional responses and morphology due to an atherogenic diet.

BACKGROUND: Diet, rich in plant polyphenols prevents atherogenesis that manifests as reduced vascular relaxation and formation of plaques. HYPOTHESIS: Atherosclerosis could be reduced by the intake of silver fir (Abies alba) extract (SFTE), rich in polyphenols. STUDY DESIGN: Chronic, in vivo treatment animal study. METHODS: Guinea pigs (Cavia porcellus) were fed for 8 weeks with one of the following three diets: atherogenic, basic or atherogenic + SFTE. After isolation, we measured the relaxation and contractile responses of the thoracic aorta. Additionally, we measured the area of fatty plaques on the aortic walls. RESULTS: Compared to the basic diet, the atherogenic diet decreased the ability of the aorta to relax by 63% (p < 0.001). The addition of SFTE to the atherogenic diet improved the aorta relaxation response compared to that of the atherogenic diet without SFTE (the decrease relative to the basic diet was 26%, p < 0.001). The aorta contractility did not differ between the groups. The SFTE group generated significantly fewer atherosclerotic plaques than did the atherogenic group. The areas of atherosclerotic plaques were 7.4, 0.3 and 1.6% in the aortas of guinea pigs receiving atherogenic, basic or atherogenic + SFTE diets, respectively. CONCLUSIONS: In a guinea pig model, prolonged treatment with antioxidative polyphenol-rich SFTE prevents aortic functional and morphological changes caused by an atherogenic diet.

The low-dose atorvastatin and valsartan combination effectively protects the arterial wall from atherogenic diet-induced impairment in the guinea pig.

New preventive strategies for atherosclerosis are needed. In this study, we tested whether a new therapeutic approach consisting of low-dose treatment with a statin and sartan combination could prevent atherogenic diet-induced impairment of the arterial wall in guinea pigs. Twenty-five Dunkin-Hartley guinea pigs were randomly assigned to five experimental groups: 1) normal diet; 2) atherogenic diet (AD); 3) AD + a low-dose atorvastatin and valsartan combination (5mg/kg/day and 2.4mg/kg/day, respectively); 4) AD + low-dose atorvastatin (5mg/kg/day); 5) AD + low-dose valsartan (2.4mg/kg/day). After 8 weeks of treatment, the animals were killed, blood samples collected and thoracic and abdominal aortas isolated. The atherogenic diet significantly impaired maximal thoracic aorta endothelium-dependent relaxation by 40.1% relative to the normal diet. The low-dose combination, compared to the separate drugs, completely preserved thoracic aorta endothelium-dependent relaxation at the level of the group receiving normal diet. This substantial effect was associated with a significant change in the expression of NOS3 (R=0.93; P=0.0002) and IL1b (R=-0.79; P=0.003) genes. In addition, treatment with the low-dose combination or the separate drugs also prevented atherosclerotic plaque formation. We found that treatment with the low-dose atorvastatin and valsartan combination has the capability to completely protect the arterial wall from atherogenic diet-induced damage in the guinea pig model. Further studies evaluating this new therapeutic approach are desirable.

Low-dose atorvastatin, losartan, and particularly their combination, provide cardiovascular protection in isolated rat heart and aorta.

Statins and angiotensin receptor blockers at therapeutic doses have beneficial cardiovascular effects, which can be applied for cardiovascular protection. We explored whether low doses of atorvastatin, losartan, and particularly their combination, possess important pleiotropic vasodilatory effects. Wistar rats were treated daily with low-dose atorvastatin (2 mg/kg, n = 15), low-dose losartan (5 mg/kg, n = 15), their combination (n = 15), or saline (n = 15). After 4, 6, or 8 weeks the animals were anesthetized, blood samples taken, and their hearts and thoracic aortas isolated. Two kinds of experiments were performed: the measurement of coronary flow rate after ischemia/reperfusion myocardial injury and endothelium-dependent relaxation of thoracic aorta. In both models, maximal vasodilation activity was obtained in rats treated for 6 weeks. In the ischemia/reperfusion myocardial injury model, coronary flow increased (atorvastatin or losartan 1.9-fold, P < 0.01; combination 2.4-fold, P < 0.001) compared with controls. In the thoracic aorta model, endothelium-dependent relaxation significantly increased only in the combination group compared with the control group (up to 1.4-fold; P < 0.01). Simultaneously, we detected increased anti-inflammatory activity and increased nitric oxide concentration, but no changes in lipids and blood pressure. In a rat model we showed important vasodilatory activity of low-dose atorvastatin, losartan, and particularly their combination. The effects of the low-dose combination were accompanied by, and probably at least partly achieved by, anti-inflammatory and nitric oxide pathways. Overall, these results could be valuable for the development of new vascular protective strategies focusing on a low-dose regimen of statins and sartans, and particularly their combination.

Treatment with low-dose atorvastatin, losartan, and their combination increases expression of vasoactive-related genes in rat aortas.

Recently it has been shown that statins and angiotensin receptor blockers (ARBs) at low doses express beneficial pleiotropic vascular effects. We aimed to explore whether these drugs at low doses induce the expression of vasoactive-related genes. Sixty adult Wistar rats were treated with low-dose atorvastatin (2 mg/kg), low-dose losartan (5 mg/kg), their combination or saline daily for 4, 6, or 8 weeks. Expression of the vasoactive-related genes endothelin receptor type A (EDNRA), endothelial nitric oxide synthase 3 (NOS3), inducible nitric oxide synthase 2 (NOS2), and angiotensin II receptor type 1 (AGTRL1a) was measured in isolated thoracic aortas. Expression of EDNRA gradually decreased, the lowest values being obtained after 8 weeks (low-dose atorvastatin, losartan [1.6- and 1-7-fold vs controls, respectively; both P < .05], and the combination [2.3-fold vs control, P < .001]). The highest values of NOS3 were obtained after 6 weeks (low-dose atorvastatin, losartan, and their combination, 3.1-fold, P < .01; 3.4-fold, P < .001; and 3.6-fold, P < .001 vs controls, respectively) and then declined after 8 weeks. The combination was more effective in inducing total NOS3 expression when compared to the separate drugs (1.4-fold; P < .05). Importantly, expression of NOS3 was associated with increased plasma NO levels and positively correlated with thoracic aorta relaxation. No changes in expression of NOS2 and AGTRL1a were observed. We showed that low-dose atorvastatin or losartan and especially their combination increases the expression of NOS3 and decreases the expression of EDNRA. These findings are valuable in explaining the effectiveness of the "low-dose pharmacological approach" for improvement in arterial function.

Recombinant single-chain antibody with the Trojan peptide penetratin positioned in the linker region enables cargo transfer across the blood-brain barrier.

Delivery of therapeutic proteins into tissues and across the blood-brain barrier (BBB) is limited by the size and biochemical properties of the proteins. Efficient delivery across BBB is generally restricted to small, highly lipophilic molecules. However, in the last decades, several peptides that can pass cell membranes have been identified. It has been shown that these peptides are also capable of delivering large hydrophilic cargoes into cells and are therefore a powerful biological tool for transporting drugs across cell membranes and even into the brain. We designed and prepared a single-chain antibody fragment (scFvs), specific for the pathological form of the prion protein (PrP(Sc)), where a cell-penetrating peptide (CPP) was used as a linker between the two variable domains of the scFv. The intravenously administered recombinant scFv-CPP was successfully targeted to and delivered into mouse brain cells. Our single-chain antibody fragments are of special interest in view of possible therapeutic reagents design not only for prion diseases but also for other neurodegenerative diseases.