959 resultados para Distal Limb


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In this paper we consider HCI's role in technology interventions for health and well-being. Three projects carried out by the authors are analysed by appropriating the idea of a value chain to chart a causal history from proximal effects generated in early episodes of design through to distal health and well-being outcomes. Responding to recent arguments that favour bounding HCI's contribution to local patterns of use, we propose an unbounded view of HCI that addresses an extended value chain of influence. We discuss a view of HCI methods as mobilising this value chain perspective in multi-disciplinary collaborations through its emphasis on early prototyping and naturalistic studies of use.

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The pathogenesis of inflammatory rheumatic diseases, including rheumatoid arthritis (RA) and spondyloarthropathies (SpAs) such as reactive arthritis (ReA), is incompletely understood. ReA is a sterile joint inflammation, which may follow a distal infection caused by Gram-negative bacteria that have lipopolysaccharide (LPS) in their outer membrane. The functions of innate immunity that may affect the pathogenesis, prognosis and treatment of these diseases were studied in this thesis. When compared with healthy controls, whole blood monocytes of healthy subjects with previous ReA showed enhanced capacity to produce TNF, an essential proinflammatory cytokine, in response to adherent conditions (mimicking vascular endothelium made adherent by inflammatory signals) and non-specific protein kinase C stimulation. Also, blood neutrophils of these subjects showed high levels of CD11b, an important adhesion molecule, in response to adherence or LPS. Thus, high responsiveness of monocytes and neutrophils when encountering inflammatory stimuli may play a role in the pathogenesis of ReA. The results also suggested that the known risk allele for SpAs, HLA-B27, may be an additive contributor to the observed differences. The promoter polymorphisms TNF 308A and CD14 (gene for an LPS receptor component) 159T were found not to increase the risk of acute arthritis. However, all female patients who developed chronic SpA had 159T and none of them had 308A, possibly reflecting an interplay between hormonal and inflammatory signals in the development of chronic SpA. Among subjects with early RA, those having the polymorphic TLR4 +896G allele (causing the Asp299Gly change in TLR4, another component of LPS receptor) required a combination of disease-modifying antirheumatic drugs to achieve remission. It is known that rapid treatment response is essential in order to maintain the patients work ability. Hence, +896G might be a candidate marker for identifying the patients who need combination treatment. The production of vascular endothelial growth factor (VEGF), which strongly promotes vascular permeability and angiogenesis that takes place e.g. early in rheumatic joints, was induced by LPS and inhibited by interferon (IFN)-alpha in peripheral blood mononuclear cells. These long-living cells might provide a source of VEGF when stimulated by LPS and migrating to inflamed joints, and the effect of IFN-alpha may contribute to the clinical efficacy of this cytokine in inhibiting joint inflammation.

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The type III secretion system (T3SS) is an essential requirement for the virulence of many Gram-negative bacteria which infect plants, animals and men. Pathogens use the T3SS to deliver effector proteins from the bacterial cytoplasm to the eukaryotic host cells, where the effectors subvert host defenses. The best candidates for directing effector protein traffic are the bacterial type III-associated appendages, called needles or pili. In plant pathogenic bacteria, the best characterized example of a T3SS-associated appendage is the HrpA pilus of the plant pathogen Pseudomonas syringae pv. tomato DC3000. The components of the T3SS in plant pathogens are encoded by a cluster of hrp (hypersensitive reaction and pathogenicity) genes. Two major classes of T3SS-secreted proteins are: harpin proteins such as HrpZ which are exported into extracellular space, and avirulence (Avr) proteins such as AvrPto which are translocated directly to the plant cytoplasm. This study deals with the structural and functional characterization of the T3SS-associated HrpA pilus and the T3SS-secreted harpins. By insertional mutagenesis analysis of HrpA, we located the optimal epitope insertion site in the amino-terminus of HrpA, and revealed the potential application of the HrpA pilus as a carrier of antigenic determinants for vaccination. By pulse-expression of proteins combined with immuno-electron microscopy, we discovered the Hrp pilus assembly strategy as addition of HrpA subunits to the distal end of the growing pilus, and we showed for the first time that secretion of HrpZ occurs at the tip of the pilus. The pilus thus functions as a conduit delivering proteins to the extracellular milieu. By using phage-display and scanning-insertion mutagenesis methods we identified a conserved HrpZ-binding peptide and localized the peptide-binding site to the central domain of HrpZ. We also found that the HrpZ specifically interacts with a host bean protein. Taken together, the current results provide deeper insight into the molecular mechanism of T3SS-associated pilus assembly and effector protein translocation, which will be helpful for further studies on the pathogenic mechanisms of Gram-negative bacteria and for developing new strategies to prevent bacterial infection.

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The modern diet has become highly sweetened, resulting in unprecedented levels of sugar consumption, particularly among adolescents. While chronic long-term sugar intake is known to contribute to the development of metabolic disorders including obesity and type II diabetes, little is known regarding the direct consequences of long-term, binge-like sugar consumption on the brain. Because sugar can cause the release of dopamine in the nucleus accumbens (NAc) similarly to drugs of abuse, we investigated changes in the morphology of neurons in this brain region following short- (4 weeks) and long-term (12 weeks) binge-like sucrose consumption using an intermittent two-bottle choice paradigm. We used Golgi-Cox staining to impregnate medium spiny neurons (MSNs) from the NAc core and shell of short- and long-term sucrose consuming rats and compared these to age-matched water controls. We show that prolonged binge-like sucrose consumption significantly decreased the total dendritic length of NAc shell MSNs compared to age-matched control rats. We also found that the restructuring of these neurons resulted primarily from reduced distal dendritic complexity. Conversely, we observed increased spine densities at the distal branch orders of NAc shell MSNs from long-term sucrose consuming rats. Combined, these results highlight the neuronal effects of prolonged binge-like intake of sucrose on NAc shell MSN morphology.

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Sensory nerve action potentials (SNAPs) and compound nerve action potentials (CNAPs) were recorded from 25 normal subjects and 21 hanseniasis patients following electrical stimulation of the median nerve at the wrist. The various nerve conduction parameters from the affected nerves of the patients were compared with those from the clinically normal nerves of patients as well as data from healthy individuals. Analysis of the data and clinical correlation studies indicate the suitability of amplitudes of the SNAPs and CNAPs rather than the nerve conduction velocities in better characterizing the neuropathy of the patients. Significantly reduced amplitudes of responses from clinically unaffected nerves of patients indicate an early stage of neuropathy, thus being of predictive value. Further, a discriminant classifier, trained on data from clinically affected nerves of patients, classified most of the data from clinically unaffected nerves of patients as abnormal. This indicates that clinical neurophysiological studies can reveal leprous neuropathy much before it becomes clinically evident by means of sensory or motor loss. A discriminant score involving only the parameters of motor threshold, amplitude of digit potential and palm nerve conduction velocity is able to classify almost all of the normal and abnormal responses. The authors hope that further confirmative studies might ultimately lead to the use of the study of distal sensory conduction in the upper limbs in possible screening of a population exposed to Mycobacterium leprae. On the other hand, misclassification of a normal person occurred and suggests that further refinement of the methods is necessary in order to facilitate wider use of the methods under held conditions.

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Background The estimated likelihood of lower limb amputation is 10 to 30 times higher amongst people with diabetes compared to those without diabetes. Of all non-traumatic amputations in people with diabetes, 85% are preceded by a foot ulcer. Foot ulceration associated with diabetes (diabetic foot ulcers) is caused by the interplay of several factors, most notably diabetic peripheral neuropathy (DPN), peripheral arterial disease (PAD) and changes in foot structure. These factors have been linked to chronic hyperglycaemia (high levels of glucose in the blood) and the altered metabolic state of diabetes. Control of hyperglycaemia may be important in the healing of ulcers. Objectives To assess the effects of intensive glycaemic control compared to conventional control on the outcome of foot ulcers in people with type 1 and type 2 diabetes. Search methods In December 2015 we searched: The Cochrane Wounds Specialised Register; The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library); Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid EMBASE; EBSCO CINAHL; Elsevier SCOPUS; ISI Web of Knowledge Web of Science; BioMed Central and LILACS. We also searched clinical trial databases, pharmaceutical trial databases and current international and national clinical guidelines on diabetes foot management for relevant published, non-published, ongoing and terminated clinical trials. There were no restrictions based on language or date of publication or study setting. Selection criteria Published, unpublished and ongoing randomised controlled trials (RCTs) were considered for inclusion where they investigated the effects of intensive glycaemic control on the outcome of active foot ulcers in people with diabetes. Non randomised and quasi-randomised trials were excluded. In order to be included the trial had to have: 1) attempted to maintain or control blood glucose levels and measured changes in markers of glycaemic control (HbA1c or fasting, random, mean, home capillary or urine glucose), and 2) documented the effect of these interventions on active foot ulcer outcomes. Glycaemic interventions included subcutaneous insulin administration, continuous insulin infusion, oral anti-diabetes agents, lifestyle interventions or a combination of these interventions. The definition of the interventional (intensive) group was that it should have a lower glycaemic target than the comparison (conventional) group. Data collection and analysis All review authors independently evaluated the papers identified by the search strategy against the inclusion criteria. Two review authors then independently reviewed all potential full-text articles and trials registry results for inclusion. Main results We only identified one trial that met the inclusion criteria but this trial did not have any results so we could not perform the planned subgroup and sensitivity analyses in the absence of data. Two ongoing trials were identified which may provide data for analyses in a later version of this review. The completion date of these trials is currently unknown. Authors' conclusions The current review failed to find any completed randomised clinical trials with results. Therefore we are unable to conclude whether intensive glycaemic control when compared to conventional glycaemic control has a positive or detrimental effect on the treatment of foot ulcers in people with diabetes. Previous evidence has however highlighted a reduction in risk of limb amputation (from various causes) in people with type 2 diabetes with intensive glycaemic control. Whether this applies to people with foot ulcers in particular is unknown. The exact role that intensive glycaemic control has in treating foot ulcers in multidisciplinary care (alongside other interventions targeted at treating foot ulcers) requires further investigation.

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There is an ongoing controversy as to which methods in total hip arthroplasty (THA) could provide young patients with best long-term results. THA is an especially demanding operation in patients with severely dysplastic hips. The optimal surgical treatment for these patients also remains controversial. The aim of this study was to evaluate the long-term survival of THA in young patients (<55 years at the time of the primary operation) on a nation-wide level, and to analyze the long-term clinical and radio-graphical outcome of uncemented THA in patients with severely dysplastic joints. Survival of 4661 primary THAs performed for primary osteoarthritis (OA), 2557 primary THAs per-formed for rheumatoid arthritis (RA), and modern uncemented THA designs performed for primary OA in young patients, were analysed from the Finnish Arthroplasty Register. A total of 68 THAs were per-formed in 56 consecutive patients with high congenital hip dislocation between 1989-1994, and 68 THAs were performed in 59 consecutive patients with severely dysplastic hips and a previous Schanz osteotomy of the femur between 1988-1995 at the Orton Orthopaedic Hospital, Helsinki, Finland. These patients underwent a detailed physical and radiographical evaluation at a mean of 12.3 years and 13.0 years postoperatively, respectively. The risk of stem revision due to aseptic loosening in young patients with primary OA was higher for cemented stems than for proximally porous-coated or HA-coated uncemented stems implanted over the 1991-2001 period. There was no difference in the risk of revision between all-poly cemented-cups and press-fit porous-coated uncemented cups implanted during the same period, when the end point was defined as any revision (including exchange of liner). All uncemented stem designs studied in young patients with primary OA had >90% survival rates at 10 years. The Biomet Bi-Metric stem had a 95% (95% CI 93-97) survival rate even at 15 years. When the end point was defined as any revision, 10 year survival rates of all uncemented cup designs except the Harris-Galante II decreased to <80%. In young patients with RA, the risk of stem revision due to aseptic loosening was higher with cemented stems than with proximally porous-coated uncemented stems. In contrast, the risk of cup revision was higher for all uncemented cup concepts than for all-poly cemented cups with any type of cup revision as the end point. The Harris hip score increased significantly (p<0.001) both in patients with high con-genital hip dislocation and in patients with severely dysplastic hips and a previous Schanz osteotomy, treated with uncemented THA. There was a negative Trendelenburg sign in 92% and in 88% of hips, respectively. There were 12 (18%) and 15 (22%) perioperative complications. The rate of survival for the CDH femoral components, with revision due to aseptic loosening as the end point, was 98% (95% CI 97-100) at 10 years in patients with high hip dislocation and 92% (95% CI, 86-99) at 14 years in patients with a previous Schanz osteotomy. The rate of survival for press-fit, porous-coated acetabular components, with revision due to aseptic loosening as the end point, was 95% (95% CI 89-100) at 10 years in patients with high hip dislocation, and 98% (95% CI 89-100) in patients with a previous Schanz osteotomy. When revision of the cup for any reason was defined as the end point, 10 year sur-vival rates declined to 88% (95% CI 81-95) and to 69% (95% CI, 56-82), respectively. For young patients with primary OA, uncemented proximally circumferentially porous- and HA-coated stems are the implants of choice. However, survival rates of modern uncemented cups are no better than that of all-poly cemented cups. Uncemented proximally circumferentially porous-coated stems and cemented all-poly cups are currently the implants of choice for young patients with RA. Uncemented THA, with placement of the cup at the level of the true acetabulum, distal advancement of the greater trochanter and femoral shortening osteotomy provided patients with high congenital hip dislocation good long-term outcomes. Most of the patients with severely dysplastic hips and a previous Schanz osteotomy can be successfully treated with the same method. However, the subtrochanteric segmental shortening with angular correction gives better leg length correction for the patients with a previous low-seated unilateral Schanz osteotomy.

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Esophageal atresia (EA), a common congenital anomaly comprising interrupted esophagus with or without a tracheoesophageal fistula (TEF), affects one in 2840 newborns. Over half have associated anomalies. After EA repair in infancy, gastroesophageal reflux (GER) and esophageal dysmotility and respiratory problems are common. As there exist no previous population-based long-term follow-up-studies on EA, its long-term sequelae are unclear. The aims of this study were to assess the cancer incidence (I), esophageal morbidity and function (II), respiratory morbidity (III), and the spinal defects (IV) in adults with repaired EA. All patients treated for EA at the Hospital for Children and Adolescents, University of Helsinki, from 1947 to 1985 were identified, and those alive with their native esophagus were contacted, and the first hundred who replied made up the study group. The patients were interviewed, they filled in symptom questionnaires, and they underwent esophageal endoscopy and manometry, pulmonary function tests, and a full orthopedic evaluation was performed with radiographs of the spine. The questionnaire was also sent by mail to adults with repaired EA not attending the clinical study, and to 287 general population-derived controls matched for age, gender, and municipality of residence. Incidence of cancer among the study population was evaluated from the population-based countrywide cancer registry. 169 (72%) adults with repaired EA replied; 101 (42%) (58 male) participated in the clinical studies at a median age of 36 years (range, 22-56). Symptomatic GER occurred in 34% and dysphagia in 85% of the patients and in 8% and 2% of the controls (P<0.001 for both). The main endoscopic findings included hiatal hernia (28%), Barrett´s esophagus (11%), esophagitis (8%), and stenotic anastomosis (8%). Histology revealed esophagitis in 25 individuals, and epithelial metaplasia in another 21. At immunohistochemistry, CDX2-positive columnar epithelial metaplasia was present in all 21 individuals, and 6 of these also demonstrated goblet cells and MUC2 positivity. In all histological groups, GER and dysphagia were equally common (P=ns). Esophageal manometry demonstrated non-propagating peristalsis in most of the patients, and low ineffective pressure of the distal esophageal body in all. The changes were significantly worse in those with epithelial metaplasia (P≤0.022). Anastomotic complications (OR 8.6-24, 95%CI 1.7-260, P=0.011-0.008), age (OR 20, 95%CI 1.3-310, P=0.034), low distal esophageal body pressure (OR 2.6, 95%CI 0.7-10, P=0.002), and defective esophageal peristalsis (OR 2.2, 95%CI 0.4-11, P=0.014) all predicted development of epithelial metaplasia. Despite the high incidence of esophageal metaplasia, none of the EA patients had suffered esophageal cancer, according to the Finnish Cancer Registry. Although three had had cancer (SIR, 1.0; 95% CI, 0.20-2.8). The overall cancer incidence among adults with repaired EA did not differ from that of the general Finnish population. Current respiratory symptoms occurred in 11% of the patients and 2% of the controls (P<0.001). Of the patients, 16%, and 6% of the controls had doctor-diagnosed asthma (P<0.001). A total of 56% and 70% of the patients and 20% and 50% of the controls had a history of pneumonia and of bronchitis (P<0.001 for both). Respiratory-related impaired quality of life was observable in 11% of the patients in contrast to 6% of the controls (P<0.001). PFT revealed obstruction in 21 of the patients, restriction in 21, and both in 36. A total of 41 had bronchial hyper-responsiveness (BHR) in HCT, and 15 others had an asthma-like response. Thoracotomy-induced rib fusion (OR 3.4, 95%CI 1.3-8.7, P=0.01) and GER-associated epithelial metaplasia in adulthood (OR 3.0, 95%CI 1.0-8.9, P=0.05) were the most significant risk factors for restrictive ventilatory defect. Vertebral anomalies were evident in 45 patients, predominating in the cervical spine in 38. The most significant risk factor for the occurrence of vertebral anomalies was any additional anomaly (OR 27, 95%C I8-100). Scoliosis (over 10 degrees) was observable in 56 patients, over 20 degrees in 11, and over 45 degrees in one. In the EA patients, risk for scoliosis over 10 degrees was 13-fold (OR 13, 95%CI 8.3-21) and over 20 degrees, 38-fold (OR 38, 95%CI 14-106) when compared to that of the general population. Thoracotomy-induced rib fusion (OR 3.6, 95%CI 0.7-19) and other associated anomalies (OR 2.1, 95%CI 0.9-2.9) were the strongest predictive factors for scoliosis. Significant esophageal morbidity associated with EA extends into adulthood. No association existed between the esophageal symptoms and histological findings. Surgical complications, increasing age, and impaired esophageal motility predicted development of epithelial metaplasia after repair of EA. According to our data, the risk for esophageal cancer is less than 500-fold that of the general population. However, the overall cancer incidence among adults with repaired EA did not differ from that of the general population. Adults with repaired EA have had significantly more respiratory symptoms and infections, as well as more asthma, and allergies than does the general population. Thoracotomy-induced rib fusion and GER-associated columnar epithelial metaplasia were the most significant risk factors for the restrictive ventilatory defect that occurred in over half the patients. Over half the patients with repaired EA are likely to develop scoliosis. Risk for scoliosis is 13-fold after repair of EA in relation to that of the general population. Nearly half the patients had vertebral anomalies. Most of these deformities were diagnosed neither in infancy nor during growth. The natural history of spinal deformities seems, however, rather benign, with spinal surgery rarely indicated.

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The prevalence and assessment of neuroleptic-induced movement disorders (NIMDs) in a naturalistic schizophrenia population that uses conventional neuroleptics were studied. We recruited 99 chronic schizophrenic institutionalized adult patients from a state nursing home in central Estonia. The total prevalence of NIMDs according to the diagnostic criteria of the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) was 61.6%, and 22.2% had more than one NIMD. We explored the reliability and validity of different instruments for measuring these disorders. First, we compared DSM-IV with the established observer rating scales of Barnes Akathisia Rating Scale (BARS), Simpson-Angus Scale (SAS) (for neuroleptic-induced parkinsonism, NIP) and Abnormal Involuntary Movement Scale (AIMS) (for tardive dyskinesia), all three of which have been used for diagnosing NIMD. We found a good overlap of cases for neuroleptic-induced akathisia (NIA) and tardive dyskinesia (TD) but somewhat poorer overlap for NIP, for which we suggest raising the commonly used threshold value of 0.3 to 0.65. Second, we compared the established observer rating scales with an objective motor measurement, namely controlled rest lower limb activity measured by actometry. Actometry supported the validity of BARS and SAS, but it could not be used alone in this naturalistic population with several co-existing NIMDs. It could not differentiate the disorders from each other. Quantitative actometry may be useful in measuring changes in NIA and NIP severity, in situations where the diagnosis has been made using another method. Third, after the relative failure of quantitative actometry to show diagnostic power in a naturalistic population, we explored descriptive ways of analysing actometric data, and demonstrated diagnostic power pooled NIA and pseudoakathisia (PsA) in our population. A subjective question concerning movement problems was able to discriminate NIA patients from all other subjects. Answers to this question were not selective for other NIMDs. Chronic schizophrenia populations are common worldwide, NIMD affected two-thirds of our study population. Prevention, diagnosis and treatment of NIMDs warrant more attention, especially in countries where typical antipsychotics are frequently used. Our study supported the validity and reliability of DSM-IV diagnostic criteria for NIMD in comparison with established rating scales and actometry. SAS can be used with minor modifications for screening purposes. Controlled rest lower limb actometry was not diagnostically specific in our naturalistic population with several co-morbid NIMDs, but it may be sensitive in measuring changes in NIMDs.

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Within the last 15 years, several new leukoencephalopathies have been recognized. However, more than half of children with cerebral white matter abnormalities still have no specific diagnosis. Our aim was to classify unknown leukoencephalopathies and to identify new diseases among them. During the study, three subgroups of patients were delineated and examined further. First, we evaluated 38 patients with unknown leukoencephalopathy. Brain MRI findings were grouped into seven categories according to the predominant location of the abnormalities. The largest subgroups were myelination abnormalities (n=20) and periventricular white matter abnormalities (n=12). Six patients had uniform MRI findings with signal abnormalities in hemispheric white matter and in selective brain stem and spinal cord tracts. Magnetic resonance spectroscopy (MRS) showed elevated lactate and decreased N-acetylaspartate in the abnormal white matter. The patients presented with ataxia, tremor, distal spasticity, and signs of dorsal column dysfunction. This phenotype - leukoencephalopathy with brain stem and spinal cord involvement and elevated white matter lactate (LBSL) - was first published elsewhere in 2003. A new finding was development of a mild axonal neuropathy. The etiopathogenesis of this disease is unknown, but elevated white matter lactate in MRS suggests a mitochondrial disorder. Secondly, we studied 22 patients with 18q deletions. Clinical and MRI findings were correlated with molecularly defined size of the deletion. All patients with deletions between markers D18S469 and D18S1141 (n=18) had abnormal myelination in brain MRI, while four patients with interstitial deletions sparing that region, had normal myelination pattern. Haploinsufficiency of myelin basic protein is suggested to be responsible for this dysmyelination. Congenital aural atresia/stenosis was found in 50% of the cases and was associated with deletions between markers D18S812 (at 18q22.3) and D18S1141 (at q23). Last part of the study comprised 13 patients with leukoencephalopathy and extensive cerebral calcifications. They showed a spectrum of findings, including progressive cerebral cysts, retinal telangiectasias and angiomas, intrauterine growth retardation, skeletal and hematologic abnormalities, and severe intestinal bleeding, which overlap with features of the previously reported patients with "Coats plus" syndrome and "leukoencephalopathy with calcifications and cysts", suggesting that these disorders are related. All autopsied patients had similar neuropathologic findings showing calcifying obliterative microangiopathy. Our patients may represent an autosomally recessively inherited disorder because there were affected siblings and patients of both sexes. We have started genealogic and molecular genetic studies of this disorder.

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Background. Cardiovascular disease (CVD) remains the most serious threat to life and health in industrialized countries. Atherosclerosis is the main underlying pathology associated with CVD, in particular coronary artery disease (CAD), ischaemic stroke, and peripheral arterial disease. Risk factors play an important role in initiating and accelerating the complex process of atherosclerosis. Most studies of risk factors have focused on the presence or absence of clinically defined CVD. Less is known about the determinants of the severity and extent of atherosclerosis in symptomatic patients. Aims. To clarify the association between coronary and carotid artery atherosclerosis, and to study the determinants associated with these abnormalities with special regard to novel cardiovascular risk factors. Subjects and methods. Quantitative coronary angiography (QCA) and B-mode ultrasound were used to assess coronary and carotid artery atherosclerosis in 108 patients with clinically suspected CAD referred for elective coronary angiography. To evaluate anatomic severity and extent of CAD, several QCA parameters were incorporated into indexes. These measurements reflected CAD severity, extent, and overall atheroma burden and were calculated for the entire coronary tree and separately for different coronary segments (i.e., left main, proximal, mid, and distal segments). Maximum and mean intima-media thickness (IMT) values of carotid arteries were measured and expressed as mean aggregate values. Furthermore, the study design included extensive fasting blood samples, oral glucose tolerance test, and an oral fat-load test to be performed in each participant. Results. Maximum and mean IMT values were significantly correlated with CAD severity, extent, and atheroma burden. There was heterogeneity in associations between IMT and CAD indexes according to anatomical location of CAD. Maximum and mean IMT values, respectively, were correlated with QCA indexes for mid and distal segments but not with the proximal segments of coronary vessels. The values of paraoxonase-1 (PON1) activity and concentration, respectively, were lower in subjects with significant CAD and there was a significant relationship between PON1 activity and concentration and coronary atherosclerosis assessed by QCA. PON1 activity was a significant determinant of severity of CAD independently of HDL cholesterol. Neither PON1 activity nor concentration was associated with carotid IMT. The concentration of triglycerides (TGs), triglyceride-rich lipoproteins (TRLs), oxidized LDL (oxLDL), and the cholesterol content of remnant lipoprotein particle (RLP-C) were significantly increased at 6 hours after intake of an oral fatty meal as compared with fasting values. The mean peak size of LDL remained unchanged 6 hours after the test meal. The correlations between total TGs, TRLs, and RLP-C in fasting and postprandial state were highly significant. RLP-C correlated with oxLDL both in fasting and in fed state and inversely with LDL size. In multivariate analysis oxLDL was a determinant of severity and extent of CAD. Neither total TGs, TRLs, oxLDL, nor LDL size were linked to carotid atherosclerosis. Insulin resistance (IR) was associated with an increased severity and extent of coronary atherosclerosis and seemed to be a stronger predictor of coronary atherosclerosis in the distal parts of the coronary tree than in the proximal and mid parts. In the multivariate analysis IR was a significant predictor of the severity of CAD. IR did not correlate with carotid IMT. Maximum and mean carotid IMT were higher in patients with the apoE4 phenotype compared with subjects with the apoE3 phenotype. Likewise, patients with the apoE4 phenotype had a more severe and extensive CAD than individuals with the apoE3 phenotype. Conclusions. 1) There is an association between carotid IMT and the severity and extent of CAD. Carotid IMT seems to be a weaker predictor of coronary atherosclerosis in the proximal parts of the coronary tree than in the mid and distal parts. 2) PON1 activity has an important role in the pathogenesis of coronary atherosclerosis. More importantly, the study illustrates how the protective role of HDL could be modulated by its components such that equivalent serum concentrations of HDL cholesterol may not equate with an equivalent, potential protective capacity. 3) RLP-C in the fasting state is a good marker of postprandial TRLs. Circulating oxLDL increases in CAD patients postprandially. The highly significant positive correlation between postprandial TRLs and postprandial oxLDL suggests that the postprandial state creates oxidative stress. Our findings emphasize the fundamental role of LDL oxidation in the development of atherosclerosis even after inclusion of conventional CAD risk factors. 4) Disturbances in glucose metabolism are crucial in the pathogenesis of coronary atherosclerosis. In fact, subjects with IR are comparable with diabetic subjects in terms of severity and extent of CAD. 5) ApoE polymorphism is involved in the susceptibility to both carotid and coronary atherosclerosis.

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The purpose of the present study was to investigate the effects of low-intensity ultrasound on bioabsorbable self-reinforced poly-L-lactide (SR-PLLA) screws and on fracture healing after SR-PLLA device fixation in experimental and clinical cancellous bone fracture. In the first experimental study, the assessment of the mechanical strengths of the SR-PLLA screws was performed after 12 weeks of daily 20-minute ultrasound exposure in vitro. In the second experimental study, 32 male Wistar rats with an experimental distal femur osteotomy fixed with an SR-PLLA rod were exposed for daily low-intensity ultrasound treatment for 21 days. The effects on the healing bone were assessed. The clinical studies consist of three prospective, randomized, and placebo-controlled series of dislocated lateral malleolar fractures fixed with one SR-PLLA screw. The total number of the patients in these series was 52. Half of the patients were provided randomly with a sham ultrasound device. The patients underwent ultrasound therapy 20 minutes daily for six weeks. Radiological bone healing was assessed both by radiographs at two, six, nine, and 12 weeks and by multidetector computed tomography (MDCT) scans at two weeks, nine weeks, and 18 months. Bone mineral density was assessed by dual-energy X-ray absorptiometry (DXA). The clinical outcome was assessed by both Olerud-Molander scoring and clinical examination of the ankle. Low-intensity ultrasound had no effects on the mechanical properties and degradation behaviour of the SR-PLLA screws in vitro. There were no obvious signs of low-intensity ultrasound-induced enhancement in the bone healing in SR-PLLA-rod-fixed metaphyseal distal femur osteotomy in rats. The biocompatibility of low-intensity ultrasound treatment and SR-PLLA was found to be good. In the clinical series low-intensity ultrasound was observed to have no obvious effects on the bone mineral density of the fractured lateral malleolus. There were no obvious differences in the radiological bone healing times of the SR-PLLA-screw-fixed lateral malleolar fractures after low-intensity ultrasound treatment. Low-intensity ultrasound did not have any effects on radiological bone morphology, bone mineral density or clinical outcome 18 months after the injury. There were no obvious findings in the present study to support the hypothesis that low-intensity pulsed ultrasound enhances bone healing in SR-PLLA-rod-fixed experimental metaphyseal distal femur osteotomy in rats or in clinical SR-PLLA-screw-fixed lateral malleolar fractures. It is important to limit the conclusions of the present set of studies only to lateral malleolar fractures fixed with an SR-PLLA screw.

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Fatigue fracture is an overuse injury commonly encountered in military and sports medicine, and known to relate to intensive or recently intensified physical activity. Bone responds to increased stress by enhanced remodeling. If physical stress exceeds bone s capability to remodel, accumulation of microfractures can lead to bone fatigue and stress fracture. Clinical diagnosis of stress fractures is complex and based on patient s anamnesis and radiological imaging. Bone stress fractures are mostly low-risk injuries, healing well after non-operative management, yet, occurring in high-risk areas, stress fractures can progress to displacement, often necessitating surgical treatment and resulting in prolonged morbidity. In the current study, the role of vitamin D as a predisposing factor for fatigue fractures was assessed using serum 25OHD level as the index. The average serum 25OHD concentration was significantly lower in conscripts with fatigue fracture than in controls. Evaluating TRACP-5b bone resorption marker as indicator of fatigue fractures, patients with elevated serum TRACP-5b levels had eight times higher probability of sustaining a stress fracture than controls. Among the 154 patients with exercise induced anterior lower leg pain and no previous findings on plain radiography, MRI revealed a total of 143 bone stress injuries in 86 patients. In 99% of the cases, injuries were in the tibia, 57% in the distal third of the tibial shaft. In patients with injury, forty-nine (57%) patients exhibited bilateral stress injuries. In a 20-year follow-up, the incidence of femoral neck fatigue fractures prior to the Finnish Defence Forces new regimen in 1986 addressing prevention of these fractures was 20.8/100,000, but rose to 53.2/100,000 afterwards, a significant 2.6-fold increase. In nineteen subjects with displaced femoral neck fatigue fractures, ten early local complications (in first postoperative year) were evident, and after the first postoperative year, osteonecrosis of the femoral head in six and osteoarthritis of the hip in thirteen patients were found. It seems likely that low vitamin D levels are related to fatigue fractures, and that an increasing trend exists between TRACP-5b bone resorption marker elevation and fatigue fracture incidence. Though seldom detected by plain radiography, fatigue fractures often underlie unclear lower leg stress-related pain occurring in the distal parts of the tibia. Femoral neck fatigue fractures, when displaced, lead to long-term morbidity in a high percentage of patients, whereas, when non-displaced, they do not predispose patients to subsequent adverse complications. Importantly, an educational intervention can diminish the incidence of fracture displacement by enhancing awareness and providing instructions for earlier diagnosis of fatigue fractures.

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Esophageal and gastroesophageal junction (GEJ) adenocarcinoma is rapidly increasing disease with a pathophysiology connected to oxidative stress. Exact pre-treatment clinical staging is essential for optimal care of this lethal malignancy. The cost-effectiviness of treatment is increasingly important. We measured oxidative metabolism in the distal and proximal esophagus by myeloperoxidase activity (MPA), glutathione content (GSH), and superoxide dismutase (SOD) in 20 patients operated on with Nissen fundoplication and 9 controls during a 4-year follow-up. Further, we assessed the oxidative damage of DNA by 8-hydroxydeoxyguanosine (8-OHdG) in esophageal samples of subjects (13 Barrett s metaplasia, 6 Barrett s esophagus with high-grade dysplasia, 18 adenocarcinoma of the distal esophagus/GEJ, and 14 normal controls). We estimated the accuracy (42 patients) and preoperative prognostic value (55 patients) of PET compared with computed tomography (CT) and endoscopic ultrasound (EUS) in patients with adenocarcinoma of the esophagus/GEJ. Finally, we clarified the specialty-related costs and the utility of either radical (30 patients) or palliative (23 patients) treatment of esophageal/GEJ carcinoma by the 15 D health-related quality-of-life (HRQoL) questionnaire and the survival rate. The cost-utility of radical treatment of esophageal/GEJ carcinoma was investigated using a decision tree analysis model comparing radical, palliative, and hypothetical new treatment. We found elevated oxidative stress ( measured by MPA) and decreased antioxidant defense (measured by GSH) after antireflux surgery. This indicates that antireflux surgery is not a perfect solution for oxidative stress of the esophageal mucosa. Elevated oxidative stress in turn may partly explain why adenocarcinoma of the distal esophagus is found even after successful fundoplication. In GERD patients, proximal esophageal mucosal anti-oxidative defense seems to be defective before and even years after successful antireflux surgery. In addition, antireflux surgery apparently does not change the level of oxidative stress in the proximal esophagus, suggesting that defective mucosal anti-oxidative capacity plays a role in development of oxidative damage to the esophageal mucosa in GERD. In the malignant transformation of Barrett s esophagus an important component appears to be oxidative stress. DNA damage may be mediated by 8-OHdG, which we found to be increased in Barrett s epithelium and in high-grade dysplasia as well as in adenocarcinoma of the esophagus/GEJ compared with controls. The entire esophagus of Barrett s patients suffers from increased oxidative stress ( measured by 8-OhdG). PET is a useful tool in the staging and prognostication of adenocarcinoma of the esophagus/GEJ detecting organ metastases better than CT, although its accuracy in staging of paratumoral and distant lymph nodes is limited. Radical surgery for esophageal/GEJ carcinoma provides the greatest benefit in terms of survival, and its cost-utility appears to be the best of currently available treatments.

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Thrombophilia (TF) predisposes both to venous and arterial thrombosis at a young age. TF may also impact the thrombosis or stenosis of hemodialysis (HD) vascular access in patients with end-stage renal disease (ESRD). When involved in severe thrombosis TF may associate with inappropriate response to anticoagulation. Lepirudin, a potent direct thrombin inhibitor (DTI), indicated for heparin-induced thrombocytopenia-related thrombosis, could offer a treatment alternative in TF. Monitoring of narrow-ranged lepirudin demands new insights also in laboratory. The above issues constitute the targets in this thesis. We evaluated the prevalence of TF in patients with ESRD and its impact upon thrombosis- or stenosis-free survival of the vascular access. Altogether 237 ESRD patients were prospectively screened for TF and thrombogenic risk factors prior to HD access surgery in 2002-2004 (mean follow-up of 3.6 years). TF was evident in 43 (18%) of the ESRD patients, more often in males (23 vs. 9%, p=0.009). Known gene mutations of FV Leiden and FII G20210A occurred in 4%. Vascular access sufficiently matured in 226 (95%). The 1-year thrombosis- and stenosis-free access survival was 72%. Female gender (hazards ratio, HR, 2.5; 95% CI 1.6-3.9) and TF (HR 1.9, 95% CI 1.1-3.3) were independent risk factors for the shortened thrombosis- and stenosis-free survival. Additionally, TF or thrombogenic background was found in relatively young patients having severe thrombosis either in hepatic veins (Budd-Chiari syndrome, BCS, one patient) or inoperable critical limb ischemia (CLI, six patients). Lepirudin was evaluated in an off-label setting in the severe thrombosis after inefficacious traditional anticoagulation without other treatment options except severe invasive procedures, such as lower extremity amputation. Lepirudin treatments were repeatedly monitored clinically and with laboratory assessments (e.g. activated partial thromboplastin time, APTT). Our preliminary studies with lepirudin in thrombotic calamities appeared safe, and no bleeds occurred. An effective DTI lepirudin calmed thrombosis as all patients gradually recovered. Only one limb amputation was performed 3 years later during the follow-up (mean 4 years). Furthermore, we aimed to overcome the limitations of APTT and confounding effects of warfarin (INR of 1.5-3.9) and lupus anticoagulant (LA). Lepirudin responses were assessed in vitro by five specific laboratory methods. Ecarin chromogenic assay (ECA) or anti-Factor IIa (anti-FIIa) correlated precisely (r=0.99) with each other and with spiked lepirudin in all plasma pools: normal, warfarin, and LA-containing plasma. In contrast, in the presence of warfarin and LA both APTT and prothrombinase-induced clotting time (PiCT®) were limited by non-linear and imprecise dose responses. As a global coagulation test APTT is useful in parallel to the precise chromogenic methods ECA or Anti-FIIa in challenging clinical situations. Lepirudin treatment requires multidisciplinary approach to ensure appropriate patient selection, interpretation of laboratory monitoring, and treatment safety. TF seemed to be associated with complicated thrombotic events, in venous (BCS), arterial (CLI), and vascular access systems. TF screening should be aimed to patients with repeated access complications or prior unprovoked thromboembolic events. Lepirudin inhibits free and clot-bound thrombin which heparin fails to inhibit. Lepirudin seems to offer a potent and safe option for treatment of severe thrombosis. Multi-centered randomized trials are necessary to assess the possible management of complicated thrombotic events with DTIs like lepirudin and seek prevention options against access complications.