922 resultados para MCAD deficiency


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Stroke, ischemic or hemorrhagic, belongs among the foremost causes of death and disability worldwide. Massive brain swelling is the leading cause of death in large hemispheric strokes and is only modestly alleviated by available treatment. Thrombolysis with tissue plasminogen activator (TPA) is the only approved therapy in acute ischemic stroke, but fear of TPA-mediated hemorrhage is often a reason for withholding this otherwise beneficial treatment. In addition, recanalization of the occluded artery (spontaneously or with thrombolysis) may cause reperfusion injury by promoting brain edema, hemorrhage, and inflammatory cell infiltration. A dominant event underlying these phenomena seems to be disruption of the blood-brain barrier (BBB). In contrast to ischemic stroke, no widely approved clinical therapy exists for intracerebral hemorrhage (ICH), which is associated with poor outcome mainly due to the mass effect of enlarging hematoma and associated brain swelling. Mast cells (MCs) are perivascularly located resident inflammatory cells which contain potent vasoactive, proteolytic, and fibrinolytic substances in their cytoplasmic granules. Experiments from our laboratory showed MC density and their state of granulation to be altered early following focal transient cerebral ischemia, and degranulating MCs were associated with perivascular edema and hemorrhage. (I) Pharmacological MC stabilization led to significantly reduced ischemic brain swelling (40%) and BBB leakage (50%), whereas pharmacological MC degranulation raised these by 90% and 50%, respectively. Pharmacological MC stabilization also revealed a 40% reduction in neutrophil infiltration. Moreover, genetic MC deficiency was associated with an almost 60% reduction in brain swelling, 50% reduction in BBB leakage, and 50% less neutrophil infiltration, compared with controls. (II) TPA induced MC degranulation in vitro. In vivo experiments with post-ischemic TPA administration demonstrated 70- to 100-fold increases in hemorrhage formation (HF) compared with controls HF. HF was significantly reduced by pharmacological MC stabilization at 3 (95%), 6 (75%), and 24 hours (95%) of follow-up. Genetic MC deficiency again supported the role of MCs, leading to 90% reduction in HF at 6 and 24 hours. Pharmacological MC stabilization and genetic MC deficiency were also associated with significant reduction in brain swelling and in neutrophil infiltration. Importantly, these effects translated into a significantly better neurological outcome and lower mortality after 24 hours. (III) Finally, in ICH experiments, pharmacological MC stabilization resulted in significantly less brain swelling, diminished growth in hematoma volume, better neurological scores, and decreased mortality. Pharmacological MC degranulation produced the opposite effects. Genetic MC deficiency revealed a beneficial effect similar to that found with pharmacological MC stabilization. In sum, the role of MCs in these clinically relevant scenarios is supported by a series of experiments performed both in vitro and in vivo. That not only genetic MC deficiency but also drugs targeting MCs could modulate these parameters (translated into better outcome and decreased mortality), suggests a potential therapeutic approach in a number of highly prevalent cerebral insults in which extensive tissue injury is followed by dangerous brain swelling and inflammatory cell infiltration. Furthermore, these experiments could hint at a novel therapy to improve the safety of thrombolytics, and a potential cellular target for those seeking novel forms of treatment for ICH.

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The objective of this study was to assess the utility of two subjective facial grading systems, to evaluate the etiologic role of human herpesviruses in peripheral facial palsy (FP), and to explore characteristics of Melkersson-Rosenthal syndrome (MRS). Intrarater repeatability and interrater agreement were assessed for Sunnybrook (SFGS) and House-Brackmann facial grading systems (H-B FGS). Eight video-recorded FP patients were graded in two sittings by 26 doctors. Repeatability for SFGS was from good to excellent and agreement between doctors from moderate to excellent by intraclass correlation coefficient and coefficient of repeatability. For H-B FGS, repeatability was from fair to good and agreement from poor to fair by agreement percentage and kappa coefficients. Because SFGS was at least as good in repeatability as H-B FGS and showed more reliable results in agreement between doctors, we encourage the use of SFGS over H-B FGS. Etiologic role of human herpesviruses in peripheral FP was studied by searching DNA of herpes simplex virus (HSV) -1 and -2, varicella-zoster virus (VZV), human herpesvirus (HHV) -6A, -6B, and -7, Epstein-Barr virus (EBV), and cytomegalovirus (CMV) by PCR/microarray methods in cerebrospinal fluid (CSF) of 33 peripheral FP patients and 36 controls. Three patients and five controls had HHV-6 or -7 DNA in CSF. No DNA of HSV-1 or -2, VZV, EBV, or CMV was found. Detecting HHV-7 and dual HHV-6A and -6B DNA in CSF of FP patients is intriguing, but does not allow etiologic conclusions as such. These DNA findings in association with FP and the other diseases that they accompanied require further exploration. MRS is classically defined as a triad of recurrent labial or oro-facial edema, recurrent peripheral FP, and plicated tongue. All three signs are present in the minority of patients. Edema-dominated forms are more common in the literature, while MRS with FP has received little attention. The etiology and true incidence of MRS are unknown. Characteristics of MRS were evaluated at the Departments of Otorhinolaryngology and Dermatology focusing on patients with FP. There were 35 MRS patients, 20 with FP and they were mailed a questionnaire (17 answered) and were clinically examined (14 patients). At the Department of Otorhinolaryngology, every MRS patient had FP and half had the triad form of MRS. Two patients, whose tissue biopsies were taken during an acute edema episode, revealed nonnecrotizing granulomatous findings typical for MRS, the other without persisting edema and with symptoms for less than a year. A peripheral blood DNA was searched for gene mutations leading to UNC-93B protein deficiency predisposing to HSV-1 infections; no gene mutations were found. Edema in most MRS FP patients did not dominate the clinical picture, and no progression of the disease was observed, contrary to existing knowledge. At the Department of Dermatology, two patients had triad MRS and 15 had monosymptomatic granulomatous cheilitis with frequent or persistent edema and typical MRS tissue histology. The clinical picture of MRS varied according to the department where the patient was treated. More studies from otorhinolaryngology departments and on patients with FP would clarify the actual incidence and clinical picture of the syndrome.

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Klinefelter syndrome (KS) is the most frequent karyotype disorder of male reproductive function. Since its original clinical description in 1942 and the identification of its chromosomal basis 47,XXY in 1959, the typical KS phenotype has become well recognized, but the mechanisms behind the testicular degeneration process have remained unrevealed. This prospective study was undertaken to increase knowledge about testicular function in adolescent KS boys. It comprised a longitudinal follow-up of growth, pubertal development, and serum reproductive hormone levels in 14 prepubertal and pubertal KS boys. Each boy had a testicular biopsy that was analyzed with histomorphometric and immunohistochemical methods. The KS boys had sufficient testosterone levels to allow normal onset and progression of puberty. Their serum testosterone levels remained within the low-normal range throughout puberty, but from midpuberty onwards, findings like a leveling-off in testosterone and insulin-like factor 3 (INSL3) concentrations, high gonadotropin levels, and exaggerated responses to gonadotropin-releasing hormone stimulation suggest diminished testosterone secretion. We also showed that the Leydig cell differentiation marker INSL3 may serve as a novel marker for onset and normal progression of puberty in boys. In the KS boys the number of germ cells was already markedly lower at the onset of puberty. The pubertal activation of the pituitary-testicular axis accelerated germ cell depletion, and germ cell differentiation was at least partly blocked at the spermatogonium or early primary spermatocyte stages. The presence of germ cells correlated with serum reproductive hormone levels. The immature Sertoli cells were incapable of transforming to the adult type, and during puberty the degeneration of Sertoli cells increased markedly. The older KS boys displayed an evident Leydig cell hyperplasia, as well as fibrosis and hyalinization of the interstitium and peritubular connective tissue. Altered immunoexpression of the androgen receptor (AR) suggested that in KS boys during puberty a relative androgen deficiency develops at testicular level. The impact of genetic features of the supernumerary X chromosome on the KS phenotype was also studied. The present study suggests that parental origin of the supernumerary X chromosome and the length of the CAG repeat of the AR gene influence pubertal development and testicular degeneration. The current study characterized by several means the testicular degeneration process in the testes of adolescent KS boys and confirmed that this process accelerates at the onset of puberty. Although serum reproductive hormone levels indicated no hypogonadism during early puberty, the histological analyses showed an already markedly reduced fertility potential in prepubertal KS boys. Genetic features of the X chromosome affect the KS phenotype.

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The prevalence of obesity is increasing at an alarming rate in all age groups worldwide. Obesity is a serious health problem due to increased risk of morbidity and mortality. Although environmental factors play a major role in the development of obesity, the identification of rare monogenic defects in human genes have confirmed that obesity has a strong genetic component. Mutations have been identified in genes encoding proteins of the leptin-melanocortin signaling system, which has an important role in the regulation of appetite and energy balance. The present study aimed at identifying mutations and genetic variations in the melanocortin receptors 2-5 and other genes active on the same signaling pathway accounting for severe early-onset obesity in children and morbid obesity in adults. The main achievement of this thesis was the identification of melanocortin-4 receptor (MC4R) mutations in Finnish patients. Six pathogenic MC4R mutations (308delT, P299H, two S127L and two -439delGC mutations) were identified, corresponding to a prevalence of 3% in severe early-onset obesity. No obesity causing MC4R mutations were found among patients with adult-onset morbid obesity. The MC4R 308delT deletion is predicted to result in a grossly truncated nonfunctional receptor of only 107 amino acids. The C-terminal residues, which are important in MC4R cell surface targeting, are totally absent from the mutant 308delT receptor. In vitro functional studies supported a pathogenic role for the S127L mutation since agonist induced signaling of the receptor was impaired. Cell membrane localization of the S127L receptor did not differ from that of the wild-type receptor, confirming that impaired function of the S127L receptor was due to reduced signaling properties. The P299H mutation leads to intracellular retention of the receptor. The -439delGC deletion is situated at a potential nescient helix-loop-helix 2 (NHLH2) -binding site in the MC4R promoter. It was demonstrated that the transcription factor NHLH2 binds to the consensus sequence at the -439delGC site in vitro, possibly resulting in altered promoter activity. Several genetic variants were identified in the melanocortin-3 receptor (MC3R) and pro-opiomelanocortin (POMC) genes. These polymorphisms do not explain morbid obesity, but the results indicate that some of these genetic variations may be modifying factors in obesity, resulting in subtle changes in obesity-related traits. A risk haplotype for obesity was identified in the ectonucleotide pyrophosphatase phosphodiesterase 1 (ENPP1) gene through a candidate gene single nucleotide polymorphism (SNP) genotyping approach. An ENPP1 haplotype, composed of SNPs rs1800949 and rs943003, was shown to be significantly associated with morbid obesity in adults. Accordingly, the MC3R, POMC and ENPP1 genes represent examples of susceptibility genes in which genetic variants predispose to obesity. In conclusion, pathogenic mutations in the MC4R gene were shown to account for 3% of cases with severe early-onset obesity in Finland. This is in line with results from other populations demonstrating that mutations in the MC4R gene underlie 1-6% of morbid obesity worldwide. MC4R deficiency thus represents the most common monogenic defect causing human obesity reported so far. The severity of the MC4-receptor defect appears to be associated with time of onset and the degree of obesity. Classification of MC4R mutations may provide a useful tool when predicting the outcome of the disease. In addition, several other genetic variants conferring susceptibility to obesity were detected in the MC3R, MC4R, POMC and ENPP1 genes.

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The New Zealand White rabbit has been widely used as a model of limbal stem cell deficiency (LSCD). Current techniques for experimental induction of LSCD utilize caustic chemicals, or organic solvents applied in conjunction with a surgical limbectomy. While generally successful in depleting epithelial progenitors, the depth and severity of injury is difficult to control using chemical-based methods. Moreover, the anterior chamber can be easily perforated while surgically excising the corneal limbus. In the interest of creating a safer and more defined LSCD model, we have therefore evaluated a mechanical debridement technique based upon use of the AlgerBrush II rotating burr. An initial comparison of debridement techniques was conducted in situ using 24 eyes in freshly acquired New Zealand White rabbit cadavers. Techniques for comparison (4 eyes each) included: (1) non-wounded control, (2) surgical limbectomy followed by treatment with 100% (v/v) n-heptanol to remove the corneal epithelium (1-2 minutes), (3) treatment of both limbus and cornea with n-heptanol alone, (4) treatment of both limbus and cornea with 20% (v/v) ethanol (2-3 minutes), (5) a 2.5-mm rounded burr applied to both the limbus and cornea, and (6) a 1-mm pointed burr applied to the limbus, followed by the 2.5-mm rounded burr applied to the cornea. All corneas were excised and processed for histology immediately following debridement. A panel of four assessors subsequently scored the degree of epithelial debridement within the cornea and limbus using masked slides. The 2.5-mm burr most consistently removed the corneal and limbal epithelia. Islands of limbal epithelial cells were occasionally retained following surgical limbectomy/heptanol treatment, or use of the 1-mm burr. Limbal epithelial cells were consistently retained following treatment with either ethanol or n-heptanol alone, with ethanol being the least effective treatment overall. The 2.5-mm burr method was subsequently evaluated in the right eye of 3 live rabbits by weekly clinical assessments (photography and slit lamp examination) for up to 5 weeks, followed by histological analyses (hematoxylin & eosin stain, periodic acid-Schiff stain and immunohistochemistry for keratin 3 and 13). All 3 eyes that had been completely debrided using the 2.5-mm burr displayed symptoms of ocular surface failure as defined by retention of a prominent epithelial defect (~40% of corneal surface at 5 weeks), corneal neovascularization (2 to 3 quadrants), reduced corneal transparency and conjunctivalization of the corneal surface (demonstrated by the presence of goblet cells and/or staining for keratin 13). In conclusion, our findings indicate that the AlgerBrush II rotating burr is an effective method for the establishment of ocular surface failure in New Zealand White rabbits. In particular, we recommend use of the 2.5-mm rotating burr for improved efficiency of epithelial debridement and safety compared to surgical limbectomy.

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Thin films of ZrO2 were prepared by reactive magnetron sputtering. Annealing of the films exhibited a drastic change in the properties due to improved crystallinity and packing density. The root mean square roughness of the sample observed from atomic force microscope is about 5.75 nm which is comparable to the average grain size of the thin film which is about 6 nm obtained from X-ray diffraction. The film annealed at 873 K exhibits an optical band gap of around 4.83 eV and shows +4 oxidation state of zirconium indicating fully oxidized zirconium, whereas higher annealing temperatures lead to oxygen deficiency in the films and this is reflected in their properties. A discontinuity in the imaginary part of the AC conductivity was observed in the frequency range of tens of thousands of Hz, where as, the real part does not show such behavior.

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Rheumatoid arthritis is the most common of all types of arthritis and despite of intensive research etiology of the disease remains unclear. Distinctive features of rheumatic arthritis comprise continuous inflammation of synovium, in which synovial membrane expands on cartilage leading to pannus tissue formation. Pannus formation, appearance of proteolytic enzymes and osteoclast formation cause articular cartilage and bone destruction, which lead to erosions and permanent joint damage. Proteolytic pathways play major roles in the development of tissue lesions in rheumatoid arthritis. Degradation of extracellular matrix proteins is essential to pannus formation and invasion. Matrix metalloproteinases (MMP) form a large proteolytic enzyme family and in rheumatoid arthritis they contribute to pannus invasion by degrading extracellular matrix and to joint destruction by directly degrading the cartilage. MMP-1 and MMP-3 are shown to be increased during cell invasion and also involved in cartilage destruction. Increase of many cytokines has been observed in rheumatoid arthritis, especially TNF-α and IL-1β are studied in synovial tissue and are involved in rheumatoid inflammation and degradation of cartilage. Underlying bone resorption requires first demineralization of bone matrix with acid secreted by osteoclasts, which exposes the collagen-rich matrix for degradation. Cathepsin K is the best known enzyme involved in bone matrix degradation, however deficiency of this protein in pycnodysostosis patient did not prevent bone erosion and on the contrary pannus tissue invading to bone did not expressed much cathepsin K. These indicate that other proteinases are involved in bone degradation, perhaps also via their capability to replace the role of other enzymes especially in diseases like pycnodysostosis or during medication e.g. using cathepsin K inhibitors. Multinuclear osteoclasts are formed also in pannus tissue, which enable the invasion into underlying bone matrix. Pannus tissue express a receptor activator of nuclear factor kappa B ligand (RANKL), an essential factor for osteoclast differentiation and a disintegrin and a metalloproteinase 8 (ADAM8), an osteoclast-activating factors, involved in formation of osteoclast-like giant cells by promoting fusion of mononuclear precursor cells. The understanding of pannus invasion and degradation of extracellular matrix in rheumatic arthritis will open us new more specific methods to prevent this destructive joint disease.

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In atherosclerosis, cholesterol accumulates in the vessel wall, mainly in the form of modified low-density lipoprotein (LDL). Macrophages of the vessel wall scavenge cholesterol, which leads to formation of lipid-laden foam cells. High plasma levels of high-density lipoprotein (HDL) protect against atherosclerosis, as HDL particles can remove peripheral cholesterol and transport it to the liver for excretion in a process called reverse cholesterol transport (RCT). Phospholipid transfer protein (PLTP) remodels HDL particles in the circulation, generating prebeta-HDL and large fused HDL particles. In addition, PLTP maintains plasma HDL levels by facilitating the transfer of post-lipolytic surface remnants of triglyceride-rich lipoproteins to HDL. Most of the cholesteryl ester transfer protein (CETP) in plasma is bound to HDL particles and CETP is also involved in the remodeling of HDL particles. CETP enhances the heteroexchange of cholesteryl esters in HDL particles for triglycerides in LDL and very low-density lipoprotein (VLDL). The aim of this thesis project was to study the importance of endogenous PLTP in the removal of cholesterol from macrophage foam cells by using macrophages derived from PLTP-deficient mice, determine the effect of macrophage-derived PLTP on the development of atherosclerosis by using bone marrow transplantation, and clarify the role of the two forms of PLTP, active and inactive, in the removal of cholesterol from the foam cells. In addition, the ability of CETP to protect HDL against the action of chymase was studied. Finally, cholesterol efflux potential of sera obtained from the study subjects was compared. The absence of PLTP in macrophages derived from PLTP-deficient mice decreased cholesterol efflux mediated by ATP-binding cassette transporter A1. The bone marrow transplantation studies showed that selective deficiency of PLTP in macrophages decreased the size of atherosclerotic lesions and caused major changes in serum lipoprotein levels. It was further demonstrated that the active form of PLTP can enhance cholesterol efflux from macrophage foam cells through generation of prebeta-HDL and large fused HDL particles enriched with apoE and phospholipids. Also CETP may enhance the RCT process, as association of CETP with reconstituted HDL particles prevented chymase-dependent proteolysis of these particles and preserved their cholesterol efflux potential. Finally, serum from high-HDL subjects promoted more efficient cholesterol efflux than did serum derived from low-HDL subjects which was most probably due to differences in the distribution of HDL subpopulations in low-HDL and high-HDL subjects. These studies described in this thesis contribute to the understanding of the PLTP/CETP-associated mechanisms underlying RCT.

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The study assessed whether plasma concentrations of complement factors C3, C4, or immunoglobulins, serum classical pathway hemolytyic activity, or polymorphisms in the class I and II HLA genes, isotypes and gene numbers of C4, or allotypes of IgG1 and IgG3 heavy chain genes were associated with severe frequently recurring or chronic mucosal infections. According to strict clinical criteria, 188 consecutive voluntary patients without a known immunodeficiency and 198 control subjects were recruited. Frequencies of low levels in IgG1, IgG2, IgG3 and IgG4 were for the first time tested from adult general population and patients with acute rhinosinusitis. Frequently recurring intraoral herpes simplex type 1 infections, a rare form of the disease, was associated with homozygosity in HLA -A*, -B*, -C*, and -DR* genes. Frequently recurrent genital HSV-2 infections were associated with low levels of IgG1 and IgG3, present in 54% of the recruited patients. This association was partly allotype-dependent. The G3mg,G1ma/ax haplotype, together with low IgG3, was more common in patients than in control subjects who lacked antibodies against herpes simplex viruses. This is the first found immunogenetic deficiency in otherwise healthy adults that predisposes to highly frequent mucosal herpes recurrences. According to previous studies, HSV effectively evades the allotype G1ma/ax of IgG1, whereas G3mg is associated with low IgG3. Certain HLA genes were more common in patients than in control subjects. Having more than one C4A or C4B gene was associated with neuralgias caused by the virus. Low levels of IgA, IgG1, IgG2, IgG3, and IgG4 were common in the general adult population, but even more frequent in patients with chronic sinusitis. Only low IgG1 was more common chronic than in acute rhinosinusitis. Clinically, nasal polyposis and bronchial asthma were associated with complicated disease forms. The best differentiating immunologic parameters were C4A deficiency and the combination of low plasma IgG4 together with low IgG1 or IgG2, performing almost equally. The lack of C4A, IgA, and IgG4, all known to possess anti-inflammatory activity, together with a concurrently impaired immunity caused by low subclass levels, may predispose to chronic disease forms. In severe chronic adult periodontitis, any C4A or C4B deficiency combined was associated with the disease. The new quantitative analysis of C4 genes and the conventional C4 allotyping method complemented each other. Lowered levels of plasma C3 or C4 or both, and serum CH50 were found in herpes and periodontitis patients. In rhinosinusitis, there was a linear trend with the highest levels found in the order: acute > chronic rhinosinusitis > general population > blood donors with no self-reported history of rhinosinusitis. Complement is involved in the defense against the tested mucosal infections. Seemingly immunocompetent patients with chronic or recurrent mucosal infections frequently have subtle weaknesses in different arms of immunity. Their susceptibility to chronic disease forms may be caused by these. Host s subtly impaired immunity often coincides with effective immune evasion from the same arms of immunity by the disease-causing pathogens. The interpretation of low subclass levels, if no additional predisposing immunologic factors are tested, is difficult and of limited value in early diagnosis and treatment.

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Background: Brachial plexus birth palsy (BPBP) most often occurs as a result of foetal-maternal disproportion. The C5 and C6 nerve roots of the brachial plexus are most frequently affected. In contrast, roots from the C7 to Th1 that result in total injury together with C5 and C6 injury, are affected in fewer than half of the patients. BPBP was first described by Smellie in 1764. Erb published his classical description of the injury in 1874 and his name became linked with the paralysis that is associated with upper root injury. Since then, early results of brachial plexus surgery have been reasonably well documented. However, from a clinical point of view not all primary results are maintained and there is also a need for later follow-up results. In addition most of the studies that are published emanate from highly specialized clinics and no nation wide epidemiological reports are available. One of the plexus injuries is the avulsion type, in which the nerve root or roots are ruptured at the neural cord. It has been speculated whether this might cause injury to the whole neural system or whether shoulder asymmetry and upper limb inequality results in postural deformities of the spine. Alternatively, avulsion could manifest as other signs and symptoms of the whole musculoskeletal system. In addition, there is no available information covering activities of daily living after obstetric brachial plexus surgery. Patients and methods: This was a population-based cross-sectional study on all patients who had undergone brachial plexus surgery with at least 5 years of follow-up. An incidence of 3.05/1000 for BPBP was obtained from the registers for this study period. A total of 1706 BPBP patients needing hospital treatment out of 1 717 057 newborns were registered in Finland between 1971 and 1997 inclusive. Of these BPBP patients, 124 (7.3%) underwent brachial plexus surgery at a mean age of 2.8 months (range: 0.4―13.2 months). Surgery was most often performed by direct neuroraphy after neuroma resection (53%). Depending on the phase of the study, 105 to 112 patients (85-90%) participated in a clinical and radiological follow-up assessment. The mean follow up time exceeded 13 years (range: 5.0―31.5 years). Functional status of the upper extremity was evaluated using Mallet, Gilbert and Raimondi scales. Isometric strength of the upper limb, sensation of the hand and stereognosis were evaluated for both the affected and unaffected sides then the differences and their ratios were calculated and recorded. In addition to the upper extremity, assessment of the spine and lower extremities were performed. Activities of daily living (ADL), participation in normal physical activities, and the use of physiotherapy and occupational therapy were recorded in a questionnaire. Results: The unaffected limb functioned as the dominant hand in all, except four patients. The mean length of the affected upper limb was 6 cm (range: 1-13.5 cm) shorter in 106 (95%) patients. Shoulder function was recorded as a mean Mallet score of 3 (range: 2―4) which was moderate. Both elbow function and hand function were good. The mean Gilbert elbow scale value was 3 (range: -1―5) and the mean Raimondi hand scale was 4 (range:1―5). One-third of the patients experienced pain in the affected limb including all those patients (n=9) who had clavicular non-union resulting from surgery. A total of 61 patients (57%) had an active shoulder external rotation of less than 0° and an active elbow extension deficiency was noted in 82 patients (77%) giving a mean of 26° (range: 5°―80°). In all, expect two patients, shoulder external rotation strength at a mean ratio 35% (range: 0―83%) and in all patients elbow flexion strength at a mean ratio of 41% (range: 0―79%) were impaired compared to the unaffected side. According to radiographs, incongruence of the glenohumeral joint was noted in 15 (16%) patients, whereas incongruence of the radiohumeral joint was found in 20 (21%) patients. Fine sensation was normal for 34/49 (69%) patients with C5-6 injury, for 15/31 (48%) with C5-7 and for only 8/25 (32%) of patients with total injury. Loss of protective sensation or absent sensation was noted in some palmar areas of the hand for 12/105 patients (11%). Normal stereognosis was recorded for 88/105 patients (84%). No significant inequalities in leg length were found and the incidence of structural scoliosis (1.7%) did not differ from that of the reference population. Nearly half of the patients (43%) had asynchronous motion of the upper limbs during gait, which was associated with impaired upper limb function. Data obtained from the completed questionnaires indicated that two thirds (63%) of the patients were satisfied with the functional outcome of the affected hand although one third of all patients needed help with ADL. Only a few patients were unable to participate in physical activities such as: bicycling, cross-country skiing or swimming. However, 71% of the patients reported problems related to the affected upper limb, such as muscle weakness and/or joint stiffness during the aforementioned activities. Incongruity of the radiohumeral joints, extent of the injury, avulsion type injury, age less than three months of age at the time of plexus surgery and inexperience of the surgeon was related to poor results as determined by multivariate analyses. Conclusions: Most of the patients had persistent sequelae, especially of shoulder function. Almost all measurements for the total injury group were poorer compared with those of the C5-6 type injury group. Most of the patients had asymmetry of the shoulder region and a shorter affected upper limb, which is a probable reason for having an abnormal gait. However, BPBP did not have an effect on normal growth of the lower extremities or the spine. Although, participation in physical activities was similar to that of the normal population, two-thirds of the patients reported problems. One-third of the patients needed help with ADL. During the period covered by this study, 7.3% BPBP of patients that needed hospital treatment had a brachial plexus operation, which amounts to fewer than 10 operations per year in Finland. It seems that better results of obstetric plexus surgery and more careful follow-up including opportunities for late reconstructive procedures will be expected, if the treatment is solely concentrated on by a few specialised teams.

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Translation initiation from the ribosomal P-site is the specialty of the initiator tRNAs (tRNA(fMet)). Presence of the three consecutive G-C base pairs (G29-C41, G30-C40 and G31-C39) in their anticodon stems, a highly conserved feature of the initiator tRNAs across the three kingdoms of life, has been implicated in their preferential binding to the P-site. How this feature is exploited by ribosomes has remained unclear. Using a genetic screen, we have isolated an Escherichia coli strain, carrying a G122D mutation in folD, which allows initiation with the tRNA(fMet) containing mutations in one, two or all the three G-C base pairs. The strain shows a severe deficiency of methionine and S-adenosylmethionine, and lacks nucleoside methylations in rRNA. Targeted mutations in the methyltransferase genes have revealed a connection between the rRNA modifications and the fundamental process of the initiator tRNA selection by the ribosome.

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Theoretical studies using density functional theory are carried out to understand the electronic structure and bonding and electronic properties of elemental beta-rhombohedral boron. The calculated band structure of ideal beta-rhombohedral boron (B-105) shows valence electron deficiency and depicts metallic behavior. This is in contrast to the experimental result that it is a semiconductor. To understand this ambiguity we discuss the electronic structure and bonding of this allotrope with cluster fragment approach using our recently proposed mno rule. This helps us to comprehend in greater detail the structure of B-105 and materials which are closely related to beta-rhombohedral boron. The molecular structures B12H12-2, B28H21+1, BeB27H21, LiB27H21-1, CB27H21+2, B57H36+3, Be3B54H36, and Li2CB54H36, and corresponding solids Li8Be3B102 and Li10CB102 are arrived at using these ideas and studied using first principles density functional theory calculations.

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This is an ethnographic study of the lived worlds of the keepers of small shops in a residential neighborhood in Seoul, South Korea. It outlines, discusses, and analyses the categories and conceptualizations of South Korean capitalism at the level of households, neighborhoods, and Korean society. These cultural categories were investigated through the neighborhood shopkeepers practices of work and reciprocal interaction as well as through the shopkeepers articulations of their lived experience. In South Korea, the keepers of small businesses have continued to be a large occupational category despite of societal and economic changes, occupying approximately one fourth of the population in active work force. In spite of that, these people, their livelihoods and their cultural and social worlds have rarely been in the focus of social science inquiry. The ethnographic field research for this study was conducted during a 14-month period between November 1998 and December 1999 and in three subsequent short visits to Korea and to the research neighborhood. The fieldwork was conducted during the aftermath of the Asian currency crisis, colloquially termed at the time as the IMF crisis, which highlighted the social and cultural circumstances of small businesskeeper in a specific way. The livelihoods of small-scale entrepreneurs became even more precarious than before; self-employment became an involuntary choice for many middle-class salaried employees who were laid off; and the cultural categories and concepts of society and economy South Korean capitalism were articulated more sharply than before. This study begins with an overview of the contemporary setting, the Korean society under the socially and economically painful outcomes of the economic crisis, and continues with an overview of relevant literature. After introducing the research area and the informants, I discuss the Korean notion of neighborhood, which incorporates both the notions of culturally valued Koreanness and deficiency in the sense of modernity and development. This study further analyses the ways in which the businesskeepers appropriate and reproduce the Korean ideas of men s and women s gender roles and spheres of work. As the appropriation of children s labor is conditional to intergenerational family trajectories which aim not to reproduce parents occupational status but to gain entry to salaried occupations via educational credentials, the work of a married couple is the most common organization of work in small businesses, to which the Korean ideas of family and kin continuity are not applied. While the lack of generational businesskeeping succession suggests that the proprietors mainly subscribe to the notions of familial status that emanate from the practices of the white-collar middle class, the cases of certain women shopkeepers show that their proprietorship and the ensuing economic standing in the family prompts and invites inversed interpretations and uses of common cultural notions of gender. After discussing and analyzing the concept of money and the cultural categorization of leisure and work, topics that emerged as very significant in the lived world of the shopkeepers, this study charts and analyses the categories of identification which the shopkeepers employ for their cultural and social locations and identities. Particular attention is paid to the idea of ordinary people (seomin), which shopkeepers are commonly considered to be most representative of, and which also sums up the ambivalence of neighborhood shopkeepers as a social category: they are not committed to familial reproduction and continuity of the business but aspire non-entrepreneurial careers for their children, while they occupy a significant position in the elaborations of culturally valued notions and ideologies defining Koreanness such as warmheartedness and sociability.

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Serum parathyroid hormone (PTH) and vitamin D are the major regulators of extracellular calcium homeostasis. The inverse association between PTH and vitamin D and the common age-related elevation of the PTH concentration are well known phenomena. However, the confounding or modifying factors of this relationship and their impact on the response of PTH levels to vitamin D supplementation need further investigation. Clinical conditions such as primary hyperparathyroidism (PHPT), renal failure and vitamin D deficiency, characterized by an elevation of the PTH concentration, have been associated with impaired long-term health outcomes. Curative treatments for these conditions have also been shown to decreases PTH concentration and attenuate some of the adverse health effects. In PHPT it has also been commonly held that hypercalcaemia, the other hallmark of the disease, is the key mediator of the adverse health outcomes. In chronic kidney disease the systemic vascular disease has been proposed to have the most important impact on general health. Some evidence also indicates that vitamin D may have significant extraskeletal actions. However, the frank elevation of PTH concentration seen in advanced PHPT and in end-stage renal failure have also been suggested to be at least partly causally related to an increased risk of death as well as cognitive dysfunction. However, the exact mechanisms have remained unclear. Furthermore, the predictive value of elevated PTH in unselected older populations has been less well studied. The studies presented in this thesis investigated the impact of age and mobility on the responses of PTH levels to vitamin D deficiency and supplementation. Furthermore, the predictive value of PTH for long-term survival and cognitive decline was addressed in an unselected population of older people. The hypothesis was that age and chronic immobility are related to a persistently blunted elevation of PTH concentration, even in the presence of chronic vitamin D deficiency, and to attenuated responses of PTH to vitamin D supplementation. It was also further hypothesized that a slightly elevated or even high-normal PTH concentration is an independent indicator of an increased risk of death and cognitive decline in the general aged population. The data of this thesis are based on three samples: a meta-analysis of published vitamin D supplementation trials, a randomized placebo controlled six-month vitamin D supplementation trial, and a longitudinal prospective cohort study on a general aged population. Based on a PubMed search, a meta-analysis of 52 clinical trials with 6 290 adult participants was performed to evaluate the impact of age and immobility on the responses of PTH to 25-OHD levels and vitamin D supplementation. A total of 218 chronically immobile, very old inpatients were also enrolled into a vitamin D supplementation trial. Mortality data for these patients was also collected after a two-year follow-up. Finally, data from the Helsinki Aging Study, which followed three random age cohorts (75, 80 and 85 years) until death in almost all subjects, was used to evaluate the predictive value of PTH for long-term survival and cognitive decline. This series of studies demonstrated that in older people without overt renal failure or severe hypercalcaemia, serum 25-OHD and PTH were closely associated, but this relationship was also affected by age and immobility. Furthermore, a substantial proportion of old chronically bedridden patients did not respond to vitamin D deficiency by elevating PTH, and the effect of a high-dose (1200 IU/d) six-month cholecalciferol supplementation on the PTH concentration was minor. This study demonstrated longitudinally for the first time that the blunted PTH also persisted over time. Even a subtle elevation of PTH to high-normal levels predicted impaired long-term health outcomes. Slightly elevated PTH concentrations indicated an increased risk of clinically significant cognitive decline and death during the last years of life in a general aged population. This association was also independent of serum ionized calcium (Ca2+) and the estimated glomerular filtration rate (GFR). A slightly elevated PTH also indicated impaired two-year survival during the terminal years of frail elderly subjects independently of Ca2+, GFR, and of 25-OHD levels. The interplay between PTH and vitamin D in the regulation of calcium homeostasis is more complex than has been generally considered. In addition to muskuloskeletal health parathyroid hormone is also related to the maintenance of other important domains of health in old age. Higher PTH concentrations, even within conventional laboratory reference ranges, seem to be an independent indicator of an increased risk of all-cause and of cardiovascular mortality, independently of established cardiovascular risk factors, disturbances in mineral metabolism, and renal failure. Limited and inconsistent evidence supports the role of vitamin D deficiency-related lack of neuroprotective effects over the causal association between PTH and impaired cognitive functions. However, the causality of these associations remains unclear. The clinical implications of the observed relationships remain to be elucidated by future studies interfering with PTH concentrations, especially by long-term interventions to reduce PTH.

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1. 1. Colon lysosome were separated by differential centrifugation and lysosomes with three different densities, probably arising from the three layers of colon, were found. 2. 2. Hypervitaminosis A resulted in a significant increase in prothrombin time which was restored to normal on vitamin K1 (20) supplementation. 3. 3. There was no appreciable change in the liver storage of vitamin A between hypervitaminotic rats receiving vitamin A and those rats receiving vitamin K1 (20) in addition to excess vitamin A. 4. 4. The colon lysosomes were unstable in hypervitaminosis A, showing an increased free activity of lysosomal enzymes like β-glucuronidase, acid phosphatase and arylsulphatase. This increase of free activity of lysoso3al enzymes in hypervitaminosis A could be prevented by oral supplementation of vitamin K1 (20). 5. 5. In "mild" vitamin A deficiency the release of arylsulphatase was significantly retarded, whereas the decreased free acid phosphatase activity was not significant. 6. 6. "Severe" vitamin A deficiency resulted in a significantly increased free activity of arylsulphatase and acid phosphatase, thus showing the instability of the lysosomal particles in this condition. 7. 7. Addition of vitamin K1 (20) to the incubation medium in vitro could prevent the vitamin A-induced release of arylsulphatase from liver lysosomes, whereas α-tocopherol was inactive. 8. 8. Retinol and retinoic acid were nearly twice as active as ethanol in the release of arylsulphatase from lysosomes in vitro, whereas 5,6-monoepoxyretinoic acid was inactive. 9. 9. The role of vitamins A and K on the lysosomal membrane structure is discussed.