917 resultados para artery


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Migraine is a highly prevalent disease, and despite several important breakthroughs there are still a many questions unanswered in the clinical, genetic and pathophysiological aspects of migraine research. Migraine has been linked to several other diseases such as epilepsy and stroke, but there are still unsolved issues concerning the true nature of these associations. Three genes predisposing to hemiplegic migraine and several loci associated to migraine have been identified, but so far no genes responsible for common forms of migraine have been recognized. Triptans have provided an important step in migraine treatment, but their usefulness in rare forms of migraine have been controversial. The Finnish Migraine Gene Project (FMGP) includes more than 1600 families and 7500 individuals. We evaluated comorbidity from 1000 consecutive subjects in the FMGP. To search for novel loci, we performed a genome-wide linkage scan in 36 families with high prevalences of migraine with visual aura. We collected 76 subjects from the FMGP who suffer from hemiplegic migraine and have used triptans. Finally, to study possible links between stroke and migraine we evaluated the prevalence of migraine in subjects with cervical artery dissection (CAD) and healthy controls. Migraine was associated with increased prevalence of allergy, hypotension and psychiatric diseases. Additionally, men suffering from migraine with aura had increased prevalence of epilepsy and stroke. Further evidence of association between migraine and epilepsy was found in our linkage study. The parametric two-point linkage analysis showed significant evidence of linkage between migraine aura and a locus on 9q21-q22. Interestingly, the same locus has been associated with occipitotemporal epilepsy. CAD seems to be a migraine risk factor, and therefore a link between stroke and migraine. Notably, CAD seems to alleviate migraine activity further indicating the association between these two conditions. Despite the contraindications of triptans, it seems that they are safe and effective in the abortive treatment of hemiplegic migraine.

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Nisäkkäillä keskushermoston uudistuminen on rajallista. Keskushermostovamman jälkeen aktivoituu monien paranemista edistävien tekijöiden lisäksi myös estäviä tekijöitä. Monella molekyylillä, kuten laminiinilla, on keskushermoston paranemista tehostava vaikutus. Laminiinit ovat myös kehon tyvikalvojen oleellisia rakennuskomponentteja. Keskushermoston laminiinit ovat tärkeitä sikiökehityksen aikana, esimerkiksi hermosäikeiden ohjauksessa. Myöhemmin ne osallistuvat veriaivoesteen ylläpitoon sekä vammojen jälkeiseen kudosreaktioon. Väitöskirjatutkimuksessani olen selvittänyt lamiiniinien, erityisesti γ1 laminiinin ja sen KDI peptidin, ekspressiota keskushermoston vammatilanteissa. Kokeellisessa soluviljelmäasetelmassa, joka simuloi vammautunutta keskushermostoympäristöä, osoitimme että KDI peptidi voimistaa sekä hermosolujen selviytymistä että hermosäikeiden kasvua. Kainihappo on glutamaattianalogi, ja glutamaattitoksisuudella uskotaan olevan tärkeä merkitys keskushermoston eri vamma- ja sairaustilanteissa tapahtuvassa hermosolukuolemassa. Toisessa väitöskirjani osatyössä osoitimme eläinmallissa KDI peptidin suojaavan rotan aivojen hippokampuksen hermosoluja kainihapon aiheuttamalta solutuholta. Elektrofysiologisilla mittauksilla osoitimme kolmannessa osatyössäni, että KDI peptidi estää glutamaattireseptorivirtoja ja suojaa siten glutamaattitoksisuudelta. Aivoveritulpan aiheuttama aivovaurio on yleinen syy aivohalvaukseen. Viimeisessä osatyössäni tutkimme eläinmallissa laminiinien ekspressiota iskemian vaurioittamassa aivokudoksessa. Laminiiniekspression todettiin voimistuvan vaurion jälkeen sekä tyvikalvo- että soluväliainerakenteissa. Vaurion ympärillä havaittiin astrosyyttejä, jotka jo melko aikaisessa vaiheessa vamman jälkeen ekspressoivat γ1 laminiinia ja KDI peptidiä. Tästä voidaan päätellä laminiinien osallistuvan aivoiskeemisen vaurion patofysiologiaan. Yleisesti väitöskirjatyöni kartoitti laminiinien ekspressiota sekä terveessä että vammautuneessa keskushermostossa. Väitöskirjatyöni tukee hypoteesia, jonka mukaan KDI peptidi suojaa keskushermostoa vaurioilta.

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Background. Hyperlipidemia is a common concern in patients with heterozygous familial hypercholesterolemia (HeFH) and in cardiac transplant recipients. In both groups, an elevated serum LDL cholesterol level accelerates the development of atherosclerotic vascular disease and increases the rates of cardiovascular morbidity and mortality. The purpose of this study is to assess the pharmacokinetics, efficacy, and safety of cholesterol-lowering pravastatin in children with HeFH and in pediatric cardiac transplant recipients receiving immunosuppressive medication. Patients and Methods. The pharmacokinetics of pravastatin was studied in 20 HeFH children and in 19 pediatric cardiac transplant recipients receiving triple immunosuppression. The patients ingested a single 10-mg dose of pravastatin, and plasma pravastatin concentrations were measured up to 10/24 hours. The efficacy and safety of pravastatin (maximum dose 10 to 60 mg/day and 10 mg/day) up to one to two years were studied in 30 patients with HeFH and in 19 cardiac transplant recipients, respectively. In a subgroup of 16 HeFH children, serum non-cholesterol sterol ratios (102 x mmol/mol of cholesterol), surrogate estimates of cholesterol absorption (cholestanol, campesterol, sitosterol), and synthesis (desmosterol and lathosterol) were studied at study baseline (on plant stanol esters) and during combination with pravastatin and plant stanol esters. In the transplant recipients, the lipoprotein levels and their mass compositions were analyzed before and after one year of pravastatin use, and then compared to values measured from 21 healthy pediatric controls. The transplant recipients were grouped into patients with transplant coronary artery disease (TxCAD) and patients without TxCAD, based on annual angiography evaluations before pravastatin. Results. In the cardiac transplant recipients, the mean area under the plasma concentration-time curve of pravastatin [AUC(0-10)], 264.1 * 192.4 ng.h/mL, was nearly ten-fold higher than in the HeFH children (26.6 * 17.0 ng.h/mL). By 2, 4, 6, 12 and 24 months of treatment, the LDL cholesterol levels in the HeFH children had respectively decreased by 25%, 26%, 29%, 33%, and 32%. In the HeFH group, pravastatin treatment increased the markers of cholesterol absorption and decreased those of synthesis. High ratios of cholestanol to cholesterol were associated with the poor cholesterol-lowering efficacy of pravastatin. In cardiac transplant recipients, pravastatin 10 mg/day lowered the LDL cholesterol by approximately 19%. Compared with the patients without TxCAD, patients with TxCAD had significantly lower HDL cholesterol concentrations and higher apoB-100/apoA-I ratios at baseline (1.0 ± 0.3 mmol/L vs. 1.4 ± 0.3 mmol/L, P = 0.031; and 0.7 ± 0.2 vs. 0.5 ± 0.1, P = 0.034) and after one year of pravastatin use (1.0 ± 0.3 mmol/L vs. 1.4 ± 0.3 mmol/L, P = 0.013; and 0.6 ± 0.2 vs. 0.4 ± 0.1, P = 0.005). Compared with healthy controls, the transplant recipients exhibited elevated serum triglycerides at baseline (median 1.3 [range 0.6-3.2] mmol/L vs. 0.7 [0.3-2.4] mmol/L, P=0.0002), which negatively correlated with their HDL cholesterol concentration (r = -0.523, P = 0.022). Recipients also exhibited higher apoB-100/apoA1 ratios (0.6 ± 0.2 vs. 0.4 ± 0.1, P = 0.005). In addition, elevated triglyceride levels were still observed after one year of pravastatin use (1.3 [0.5-3.5] mmol/L vs. 0.7 [0.3-2.4] mmol/L, P = 0.0004). Clinically significant elevations in alanine aminotransferase, creatine kinase, or creatinine ocurred in neither group. Conclusions. Immunosuppressive medication considerably increased the plasma pravastatin concentrations. In both patient groups, pravastatin treatment was moderately effective, safe, and well tolerated. In the HeFH group, high baseline cholesterol absorption seemed to predispose patients to insufficient cholesterol-lowering efficacy of pravastatin. In the cardiac transplant recipients, low HDL cholesterol and a high apoB-100/apoA-I ratio were associated with development of TxCAD. Even though pravastatin in the transplant recipients effectively lowered serum total and LDL cholesterol concentrations, it failed to normalize their elevated triglyceride levels and, in some patients, to prevent the progression of TxCAD.

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Listening to music involves a widely distributed bilateral network of brain regions that controls many auditory perceptual, cognitive, emotional, and motor functions. Exposure to music can also temporarily improve mood, reduce stress, and enhance cognitive performance as well as promote neural plasticity. However, very little is currently known about the relationship between music perception and auditory and cognitive processes or about the potential therapeutic effects of listening to music after neural damage. This thesis explores the interplay of auditory, cognitive, and emotional factors related to music processing after a middle cerebral artery (MCA) stroke. In the acute recovery phase, 60 MCA stroke patients were randomly assigned to a music listening group, an audio book listening group, or a control group. All patients underwent neuropsychological assessments, magnetoencephalography (MEG) measurements, and magnetic resonance imaging (MRI) scans repeatedly during a six-month post-stroke period. The results revealed that amusia, a deficit of music perception, is a common and persistent deficit after a stroke, especially if the stroke affects the frontal and temporal brain areas in the right hemisphere. Amusia is clearly associated with deficits in both auditory encoding, as indicated by the magnetic mismatch negativity (MMNm) response, and domain-general cognitive processes, such as attention, working memory, and executive functions. Furthermore, both music and audio book listening increased the MMNm, whereas only music listening improved the recovery of verbal memory and focused attention as well as prevented a depressed and confused mood during the first post-stroke months. These findings indicate a close link between musical, auditory, and cognitive processes in the brain. Importantly, they also encourage the use of listening to music as a rehabilitative leisure activity after a stroke and suggest that the auditory environment can induce long-term plastic changes in the recovering brain.

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In the recent time CFD tools have become increasingly useful in the engineering design studies especially in the area of aerospace vehicles. This is largely due to the advent of high speed computing platforms in addition to the development of new efficient algorithms. The algorithms based on kinetic schemes have been shown to be very robust and further meshless methods offer certain advantages over the other methods. Preliminary investigations of blood flow visualization through artery using CFD tool have shown encouraging results which further needs to be verified and validated.

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Background: The improved prognosis of early preterm birth has created a generation of surviving very low birth weight (< 1500 g, VLBW) infants whose health risks in adulthood are poorly known. Of every 1000 live-born infants in Finland, about 8 are born at VLBW. Variation in birth weight, even within the normal range, relates to considerable variation in the risk for several common adult disorders, including cardiovascular disease and osteoporosis. Small preterm infants frequently exhibit severe postnatal or prenatal growth retardation, or both. Much reason for concern thus exists, regarding adverse health effects in surviving small preterm infants later lives. We studied young adults, aiming at exploring whether VLBW birth and postnatal events after such a birth are associated with higher levels of risk factors for cardiovascular disease or osteoporosis. Subjects and Methods: A follow-up study for VLBW infants began in 1978; by the end of 1985, 335 VLBW survivors at Helsinki University Central Hospital participated in the follow-up. Their gestational ages ranged from 24 to 35 weeks, mean 29.2 and standard deviation 2.2 weeks. In 2004, we invited for a clinic visit 255 subjects, aged 18 to 27, who still lived in the greater Helsinki area. From the same birth hospitals, we also invited 314 term-born controls of similar age and sex. These two study groups underwent measurements of body size and composition, function of brachial arterial endothelium (flow-mediated dilatation, FMD) and carotid artery intima-media thickness (cIMT) by ultrasound. In addition, we measured plasma lipid concentrations, ambulatory blood pressure, fasting insulin, glucose tolerance and, by dual-energy x-ray densitometry, bone-mineral density. Results: 172 control and 166 VLBW participants underwent lipid measurements and a glucose tolerance test. VLBW adults fasting insulin (adjusted for body mass index) was 12.6% (95% confidence interval, 0.8 to 25.8) higher than that of the controls. The glucose and insulin concentrations 120 minutes after 75 g glucose ingestion showed similar differences (N=332) (I). VLBW adults had 3.9 mmHg (1.3 to 6.4) higher office systolic blood pressure, 3.5 mmHg (1.7 to 5.2) higher office diastolic blood pressure (I), and, when adjusted for body mass index and height, 3.1 mmHg (0.5 to 5.5) higher 24-hour mean systolic blood pressure (N=238) (II). VLBW birth was associated neither with HDL- or total cholesterol nor triglyceride concentrations (N=332) (I), nor was it associated with a low FMD or a high cIMT (N=160) (III). VLBW adults had 0.51-unit (0.28 to 0.75) lower lumbar spine Z scores and 0.56-unit (0.34 to 0.78) lower femoral neck Z scores (N=283). Adjustments for size attenuated the differences, but only partially (IV). Conclusions: These results imply that those born at VLBW, although mostly healthy as young adults, already bear several risk factors for chronic adult disease. The significantly higher fasting insulin level in adults with VLBW suggests increased insulin resistance. The higher blood pressure in young adults born at VLBW may indicate they later are at risk for hypertension, although their unaffected endothelial function may be evidence for some form of protection from cardiovascular disease. Lower bone mineral density around the age of peak bone mass may suggest increased risk for later osteoporotic fractures. Because cardiovascular disease and osteoporosis are frequent, and their prevention is relatively cheap and safe, one should focus on prevention now. When initiated early, preventive measures are likely to have sufficient time to be effective in preventing or postponing the onset of chronic disease.

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Background: The improved prognosis of early preterm birth has created a generation of surviving very low birth weight (PIENEMPI KUIN 1500 g, VLBW) infants whose health risks in adulthood are poorly known. Of every 1000 live-born infants in Finland, about 8 are born at VLBW. Variation in birth weight, even within the normal range, relates to considerable variation in the risk for several common adult disorders, including cardiovascular disease and osteoporosis. Small preterm infants frequently exhibit severe postnatal or prenatal growth retardation, or both. Much reason for concern thus exists, regarding adverse health effects in surviving small preterm infants later lives. We studied young adults, aiming at exploring whether VLBW birth and postnatal events after such a birth are associated with higher levels of risk factors for cardiovascular disease or osteoporosis. Subjects and Methods: A follow-up study for VLBW infants began in 1978; by the end of 1985, 335 VLBW survivors at Helsinki University Central Hospital participated in the follow-up. Their gestational ages ranged from 24 to 35 weeks, mean 29.2 and standard deviation 2.2 weeks. In 2004, we invited for a clinic visit 255 subjects, aged 18 to 27, who still lived in the greater Helsinki area. From the same birth hospitals, we also invited 314 term-born controls of similar age and sex. These two study groups underwent measurements of body size and composition, function of brachial arterial endothelium (flow-mediated dilatation, FMD) and carotid artery intima-media thickness (cIMT) by ultrasound. In addition, we measured plasma lipid concentrations, ambulatory blood pressure, fasting insulin, glucose tolerance and, by dual-energy x-ray densitometry, bone-mineral density. Results: 172 control and 166 VLBW participants underwent lipid measurements and a glucose tolerance test. VLBW adults fasting insulin (adjusted for body mass index) was 12.6% (95% confidence interval, 0.8 to 25.8) higher than that of the controls. The glucose and insulin concentrations 120 minutes after 75 g glucose ingestion showed similar differences (N=332) (I). VLBW adults had 3.9 mmHg (1.3 to 6.4) higher office systolic blood pressure, 3.5 mmHg (1.7 to 5.2) higher office diastolic blood pressure (I), and, when adjusted for body mass index and height, 3.1 mmHg (0.5 to 5.5) higher 24-hour mean systolic blood pressure (N=238) (II). VLBW birth was associated neither with HDL- or total cholesterol nor triglyceride concentrations (N=332) (I), nor was it associated with a low FMD or a high cIMT (N=160) (III). VLBW adults had 0.51-unit (0.28 to 0.75) lower lumbar spine Z scores and 0.56-unit (0.34 to 0.78) lower femoral neck Z scores (N=283). Adjustments for size attenuated the differences, but only partially (IV). Conclusions: These results imply that those born at VLBW, although mostly healthy as young adults, already bear several risk factors for chronic adult disease. The significantly higher fasting insulin level in adults with VLBW suggests increased insulin resistance. The higher blood pressure in young adults born at VLBW may indicate they later are at risk for hypertension, although their unaffected endothelial function may be evidence for some form of protection from cardiovascular disease. Lower bone mineral density around the age of peak bone mass may suggest increased risk for later osteoporotic fractures. Because cardiovascular disease and osteoporosis are frequent, and their prevention is relatively cheap and safe, one should focus on prevention now. When initiated early, preventive measures are likely to have sufficient time to be effective in preventing or postponing the onset of chronic disease.

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We investigated the associations of anger and cynicism with carotid artery intima-media thickness (IMT) and whether these associations were moderated by childhood or adulthood socioeconomic status (SES). The participants were 647 men and 893 women derived from the population-based Cardiovascular Risk in Young Finns Study. Childhood SES was measured in 1980 when the participants were aged 3-18. In 2001, adulthood SES, anger, cynicism, and IMT were measured. There were no associations between anger or cynicism and IMT in the entire population, but anger was associated with thicker IMT in participants who had experienced low SES in childhood. This association persisted after adjustment for a host of cardiovascular risk factors. It is concluded that the ill health-effects of psychological factors such as anger may be more pronounced in individuals who have been exposed to adverse socioeconomic circumstances early in life.

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There is a widespread reporting habit of combining the outcomes for patients with rest pain (Fontaine III) and tissue loss (Fontaine IV) under the single category of critical leg ischaemia (CLI). This study focused on patients with ischaemic tissue loss treated with infrainguinal bypass surgery (IBS). All patients included in the study were treated at Helsinki University Central Hospital in 2000-2007. First, ulcer healing time after IBS and factors influencing healing time were prospectively assessed in 2 studies including 148 and 110 patients, respectively. Second,the results of redo IBS were retrospectively evaluated in 593 patients undergoing primary IBS for CLI with tissue loss . Third,long-term outcome were retrospectively analysed in 636 patients who underwent IBS for CLI with tissue loss . Fourth, the outcome of IBS was retrospectively compared with endovascular treatment (PTA) of the infrapopliteal arteries in 1023 CLI patients. Fifth, the influence multidrug resistant Pseudomans aeruginosa (MDR Pa) bacteria contamination in CLI patients treated with IBS was retropectively assessed. Sixty-four patients with positive MDR Pa -culture were matched with 64 MDR Pa - negative controls. Complete ulcer healing rate, including the ischemic ulcers and incisional wounds, was 40% at 6 months after IBS and 75% at one year. Diabetes was a risk factor for prolonged complete ulcer healing time. Ischaemic tissue lesions located in mid-and hindfoot healed poorly. At one year after IBS 50% of the patients were alive with salvaged leg and completely healed ulcers. The absence of gap between tertiary graft patency and leg salvage rates indicates the importance of a patent infrainguinal graft to save a leg with ischaemic tissue loss. Long-term survival for patients with ischaemic tissue loss was poor, 38% at 5 years. Only 30% of the patients were alive without amputation at 5 years. Several of the patient comorbidities increased independently the mortality risk; coronary artery disease, renal insufficiency, chronic obstructive lung disease and high age. When both PTA and bypass is feasible, infrapopliteal PTA as a first-line strategy is expected to achieve similar long-term results to bypass surgery in CLI when redo surgery is actively utilized. MDR Pa in a patient with CLI should be considered as a serious event with increased risk of early major amputation or death. Conclusion: Despite a successful infrainguinal bypass healing of the ischaemic ulcers and incisional wounds ulcer healing is a slow process especially in diabetics. Bypass surgery and PTA improve the outcome of the ischaemic leg but the mortality rate of the patients is high due to their severe comorbidities.

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The main purpose of revascularization procedures for critical limb ischaemia (CLI) is to preserve the leg and sustain the patient s ambulatory status. Other goals are ischaemic pain relief and healing of ischaemic ulcers. Patients with CLI are usually old and have several comorbidities affecting the outcome. Revascularization for CLI is meaningless unless both life and limb are preserved. Therefore, the knowledge of both patient- and bypass-related risk factors is of paramount importance in clinical decision-making, patient selection and resource allocation. The aim of this study was to identify patient- and graft-related predictors of impaired outcome after infrainguinal bypass for CLI. The purpose was to assess the outcome of high-risk patients undergoing infrainguinal bypass and to evaluate the usefulness of specific risk scoring methods. The results of bypasses in the absence of optimal vein graft material were also evaluated, and the feasibility of the new method of scaffolding suboptimal vein grafts was assessed. The results of this study showed that renal insufficiency - not only renal failure but also moderate impairment in renal function - seems to be a significant risk factor for both limb loss and death after infrainguinal bypass in patients with CLI. Low estimated GFR (PIENEMPI KUIN 30 ml/min/1.73 m2) is a strong independent marker of poor prognosis. Furthermore, estimated GFR is a more accurate predictor of survival and leg salvage after infrainguinal bypass in CLI patients than serum creatinine level alone. We also found out that the life expectancy of octogenarians with CLI is short. In this patient group endovascular revascularization is associated with a better outcome than bypass in terms of survival, leg salvage and amputation-free survival especially in presence of coronary artery disease. This study was the first one to demonstrate that Finnvasc and modified Prevent III risk scoring methods both predict the long-term outcome of patients undergoing both surgical and endovascular infrainguinal revascularization for CLI. Both risk scoring methods are easy to use and might be helpful in clinical practice as an aid in preoperative patient selection and decision-making. Similarly than in previous studies, we found out that a single-segment great saphenous vein graft is superior to any other autologous vein graft in terms of mid-term patency and leg salvage. However, if optimal vein graft is lacking, arm vein conduits are superior to prosthetic grafts especially in infrapopliteal bypasses for CLI. We studied also the new method of scaffolding suboptimal quality vein grafts and found out that this method may enable the use of vein grafts of compromised quality otherwise unsuitable for bypass grafting. The remarkable finding was that patients with the combination of high operative risk due to severe comorbidities and risk graft have extremely poor survival, suggesting that only relatively fit patients should undergo complex bypasses with risk grafts. The results of this study can be used in clinical practice as an aid in preoperative patient selection and decision-making. In the future, the need of vascular surgery will increase significantly as the elderly and diabetic population increases, which emphasises the importance of focusing on those patients that will gain benefit from infrainguinal bypass. Therefore, the individual risk of the patient, ambulatory status, outcome expectations, the risk of bypass procedure as well as technical factors such as the suitability of outflow anatomy and the available vein material should all be assessed and taken into consideration when deciding on the best revascularization strategy.

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Unilateral ischemia in the right cerebral hemisphere of the rat was induced by ligation of the right common carotid artery coupled with controlled hemorrhage to produce hypotension (25±8 mm/Hg). Where indicated after 30 min of ischemia, the withdrawn blood was reinfused to restore arterial pressure to normal. Mitochondria isolated from the ipsilateral hemisphere after 30 min of ischemia showed significantly lower respiratory rates than the organelles isolated from the contralateral side. Oxidation of NAD+-linked substrates was more sensitive to inhibition in ischemia (30%) than was of ferrocytochromec (12%), succinate oxidation being intermediate. The activities of membrane-bound dehydrogenases (both NADH and succinate-linked) were also significantly lowered. Ischemia did not affect the cytochrome content of mitochondria. Respiratory activity (NAD+-linked) of mitochondria isolated from the ipsilateral hemisphere was twice as sensitive to inhibition by fatty acid as was of preparations from the contralateral side. Mitochondria isolated from cerebral cortex after 90 min of post-ischemic reperfusion showed no significant improvement in the rate of substrate oxidation. Adenine nucleotide translocase activity and energy-dependent Ca2+ uptake, both of which decreased significantly in mitochondria isolated from the ischemic brain, showed little recovery, on reperfusion. These observations suggested the strong possibility that the deleterious effects of ischemia on mitochondrial respiratory function might be mediated by free fatty acids that are known to accumulate in large amounts in ischemic tissues. The pattern of inhibition of ATPase activity was consistent with this view.

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Heart failure is a common, severe, and progressive condition associated with high mortality and morbidity. Because of population-aging in the coming decades, heart failure is estimated to reach epidemic proportions. Current medical and surgical treatments have reduced mortality, but the prognosis for patients has remained poor. Transplantation of skeletal myoblasts has raised hope of regenerating the failing heart and compensating for lost cardiac contractile tissue. In the present work, we studied epicardial transplantation of tissue-engineered myoblast sheets for treatment of heart failure. We employed a rat model of myocardial infarction-induced acute and chronic heart failure by left anterior descending coronary artery ligation. We then transplanted myoblast sheets genetically modified to resist cell death after transplantation by expressing antiapoptotic gene bcl2. In addition, we evaluated the regenerative capacity of myoblast sheets expressing the cardioprotective cytokine hepatocyte growth factor in a rat chronic heart failure model. Furthermore, we utilized in vitro cardiomyocyte and endothelial cell culture models as well as microarray gene expression analysis to elucidate molecular mechanisms mediating the therapeutic effects of myoblast sheet transplantation. Our results demonstrate that Bcl2-expression prolonged myoblast sheet survival in rat hearts after transplantation and induced secretion of cardioprotective, proangiogenic cytokines. After acute myocardial infarction, these sheets attenuated left ventricular dysfunction and myocardial damage, and they induced therapeutic angiogenesis. In the chronic heart failure model, inhibition of graft apoptosis by Bcl-2 improved cardiac function, supported survival of cardiomyocytes in the infarcted area, and induced angiogenesis in a vascular endothelial growth factor receptor 1- and 2-dependent mechanism. Hepatocyte growth factor-secreting myoblast sheets further enhanced the angiogenic efficacy of myoblast sheet therapy. Moreover, myoblast-secreted paracrine factors protected cardiomyocytes against oxidative stress in an epidermal growth factor receptor- and c-Met dependent manner. This protection was associated with induction of antioxidative genes and activation of the unfolded protein response. Our results provide evidence that inhibiting myoblast sheet apoptosis can enhance the sheets efficacy for treating heart failure after acute and chronic myocardial infarction. Furthermore, we show that myoblast sheets can serve as vehicles for delivery of growth factors, and induce therapeutic angiogenesis in the chronically ischemic heart. Finally, myoblasts induce, in a paracine manner, a cardiomyocyte-protective response against oxidative stress. Our study elucidates novel mechanisms of myoblast transplantation therapy, and suggests effective means to improve this therapy for the benefit of the heart failure patient.

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According to a large body of evidence, carotid endarterectomy (CEA) can prevent strokes, provided that appropriate inclusion criteria and high-quality perioperative treatment methods are utilised with low complication rates. From the patient s perspective, it is of paramount importance that the operation is as safe and effective as possible. From the community s point of view, it is important that CEA provision prevents as many strokes as possible. In order to define the stroke preventing potential of CEA in different communities, a comparison between eight European countries and Australia was performed including 53 077 carotid interventions. A more detailed evaluation was performed in Finland, the United Kingdom and Egypt. It could be estimated that many potentially preventable strokes occur due to insufficient diagnostics and CEA provision. The number of CEAs should be at least doubled in the Helsinki region. The theoretical power of CEA provision in stroke prevention varied significantly between the countries. Delay from symptom to surgery has been identified as one of the most important factors influencing the effectiveness of CEA. In 2008 only 11% of CEAs in Helsinki university central hospital (HUCH) were performed within the recommended14 days. Registered data of 673 CEAs in HUCH during 2000-2005 was analyzed. There was no systematic error that would have changed the outcome analysis. However it is important that registers are audited regularly and cross matching of different registries is possible. A previously unpublished method of combining medial mandibulotomy, neck incision and carotid artery interposition was carried out as a collaboration of maxillofacial, ear, nose and throat and vascular surgeons. Five patients were operated on with a technique that was feasible and possible to perform with little morbidity, but due to the significant risks involved, this technique should be reserved for carefully selected cases. In stroke prevention, organisational decisions seem far more important than details in interventional procedures when CEA is performed with low complication rates, as was the case in the present study. A TIA clinic approach with close co-operation between the on-call vascular surgeons, neurologists and radiologists should be available at all centres treating these patients. Patients should have a direct and fast admission to the hospital performing CEA.

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Internal haemorrhage, often leading to cardio-vascular arrest happens to be one of the prime sources of high fatality rates in mammals. We propose a simplistic model of fluid flow in our attempt to specify the location of the haemorrhagic spot, which, if located accurately, could possibly be operated leading to an instant cure. The model we employ for the purpose is basically fluid mechanical in origin and consists of a viscous fluid, pumped by a periodic force and flowing through an elastic tube. The analogy is with that of blood, pumped from the heart and flowing through an artery or vein. Our results, aided by graphical illustrations, match reasonably well with experimental observations.

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The present study was to investigate the effect of W. calendulacea on ischemia and reperfusion-induced cerebral injury. Cerebral ischemia was induced by occluding right and left common carotid arteries (global cerebral ischemia) for 30 min followed by reperfusion for 1 h and 4 h individually. Various biochemical alterations, produced subsequent to the application of bilateral carotid artery occlusion (BCAO) followed by reperfusion viz. increase in lipid peroxidation (LPO), hydrogen peroxide (H(2)O(2)), and decrease in reduced glutathione (GSH), catalase (CAT) and superoxide dismutase (SOD), level in the brain tissue, Western blot analysis (Cu-Zn-SOD and CAT) and assessment of cerebral infarct size were measured. All those enzymes are markedly reversed and restored to near normal level in the groups pre-treated with W. calendulacea (250 and 500 mg/kg given orally in single and double dose/day for 10 days) in dose-dependent way. The effect of W. calendulacea had increased significantly the protein expression of copper/zinc superoxide dismutase (Cu-Zn-SOD) and CAT in cerebral ischemia. W. claendulacea was markedly decrease cerebral infarct damages but results are not statistically significant. It can be concluded that W. calendulacea possesses a neuroprotective activity against cerebral ischemia in rat.