116 resultados para bio update
Resumo:
Ilio-femoral deep vein thrombosis (DVT) has a high rate of long-term morbidity in the form of the postthrombotic syndrome (PTS). Therefore, management of acute thrombosis should not only focus on the prevention of acute complications such as propagation or embolisation of the initial clot but also on preventing PTS and recurrent thrombosis. Contemporary catheter-based treatments of deep vein thrombosis have proven to be safe and effective in selected patients. Current guidelines recommend medical therapy with anticoagulation alone for all but the most severe, limb-threatening thrombosis. They additionally allow for consideration of catheter-based treatment in patients with acute DVT and low risk of bleeding complications to prevent PTS. Recent studies favoring interventional therapy have not been included in these guidelines. Data on long-term outcome is expected to be published soon, clarifying and very likely strengthening the role of catheter-based treatments in the management of acute ilio-femoral DVT.
Resumo:
OBJECTIVE: To describe and evaluate psychosocial factors in nonorganic voice disorders (NVDs). Nonorganic voice disorders are presumed to be the result of increased muscular tension that is caused to varying extents by vocal misuse and emotional stress. It is therefore necessary to include both of these in the diagnosis and treatment of patients with voice disorders. DESIGN: Clinical survey. SETTING: Academic tertiary referral center. PATIENTS: To evaluate psychosocial factors in NVDs, a sample of 74 patients with NVDs was examined psychologically using the Giessen Test and Picture Frustration Test. The results were compared with a control group of 19 patients with an organic dysphonia (vocal cord paralysis). MAIN OUTCOME MEASURES: Six scales of the Giessen Test (social response, dominance, control, underlying mood, permeability, and social potency), 3 reaction types of the Picture Frustration Test (obstacle dominance, ego defense, and need persistence), and 3 aggression categories of the Picture Frustration Test (extrapunitivity, intropunitivity, and impunitivity). RESULTS: The most striking significant difference between the 2 groups was that in conflict situations, patients with NVDs sought a quick solution or expected other people to provide one, which prevented them from understanding the underlying causes of the conflict. CONCLUSIONS: Only if the psychosocial aspects are taken into account can patients with NVD be offered a therapy that treats the causes of the voice disorder. It must be decided individually whether and when a voice training approach or a more psychological-psychotherapeutical approach is preferable.
Resumo:
Lung stereology has a long and successful tradition. From mice to men, the application of new stereological methods at several levels (alveoli, parenchymal cells, organelles, proteins) has led to new insights into normal lung architecture, parenchymal remodelling in emphysema-like pathology, alveolar type II cell hyperplasia and hypertrophy and intracellular surfactant alterations as well as distribution of surfactant proteins. The Euler number of the network of alveolar openings, estimated using physical disectors at the light microscopic level, is an unbiased and direct estimate of alveolar number. Surfactant-producing alveolar type II cells can be counted and sampled for local size estimation with physical disectors at a high magnification light microscopic level. The number of their surfactant storage organelles, lamellar bodies, can be estimated using physical disectors at the EM level. By immunoelectron microscopy, surfactant protein distribution can be analysed with the relative labelling index. Together with the well-established classical stereological methods, these design-based methods now allow for a complete quantitative phenotype analysis in lung development and disease, including the structural characterization of gene-manipulated mice, at the light and electron microscopic level.
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ABSTRACT: Particulate air pollution has been associated with respiratory and cardiovascular disease. Evidence for cardiovascular and neurodegenerative effects of ambient particles was reviewed as part of a workshop. The purpose of this critical update is to summarize the evidence presented for the mechanisms involved in the translocation of particles from the lung to other organs and to highlight the potential of particles to cause neurodegenerative effects.Fine and ultrafine particles, after deposition on the surfactant film at the air-liquid interface, are displaced by surface forces exerted on them by surfactant film and may then interact with primary target cells upon this displacement. Ultrafine and fine particles can then penetrate through the different tissue compartments of the lungs and eventually reach the capillaries and circulating cells or constituents, e.g. erythrocytes. These particles are then translocated by the circulation to other organs including the liver, the spleen, the kidneys, the heart and the brain, where they may be deposited. It remains to be shown by which mechanisms ultrafine particles penetrate through pulmonary tissue and enter capillaries. In addition to translocation of ultrafine particles through the tissue, fine and coarse particles may be phagocytized by macrophages and dendritic cells which may carry the particles to lymph nodes in the lung or to those closely associated with the lungs. There is the potential for neurodegenerative consequence of particle entry to the brain. Histological evidence of neurodegeneration has been reported in both canine and human brains exposed to high ambient PM levels, suggesting the potential for neurotoxic consequences of PM-CNS entry. PM mediated damage may be caused by the oxidative stress pathway. Thus, oxidative stress due to nutrition, age, genetics among others may increase the susceptibility for neurodegenerative diseases. The relationship between PM exposure and CNS degeneration can also be detected under controlled experimental conditions. Transgenic mice (Apo E -/-), known to have high base line levels of oxidative stress, were exposed by inhalation to well characterized, concentrated ambient air pollution. Morphometric analysis of the CNS indicated unequivocally that the brain is a critical target for PM exposure and implicated oxidative stress as a predisposing factor that links PM exposure and susceptibility to neurodegeneration.Together, these data present evidence for potential translocation of ambient particles on organs distant from the lung and the neurodegenerative consequences of exposure to air pollutants.
Resumo:
Glucocorticosteroid-induced spinal osteoporosis (GIOP) is the most frequent of all secondary types of osteoporosis. The understanding of the pathophysiology of glucocorticoid (GC) induced bone loss is of crucial importance for appropriate treatment and prevention of debilitating fractures that occur predominantly in the spine. GIOP results from depressed bone formation due to lower activity and higher death rate of osteoblasts on the one hand, and from increase bone resorption due to prolonged lifespan of osteoclasts on the other. In addition, calcium/phosphate metabolism may be disturbed through GC effects on gut, kidney, parathyroid glands and gonads. Therefore, therapeutic agents aim at restoring balanced bone cell activity by directly decreasing apoptosis rate of osteoblasts (e.g., cyclical parathyroid hormone) or by increasing apoptosis rate of osteoclasts (e.g., bisphosphonates). Other therapeutical efforts aim at maintaining/restoring calcium/phosphate homeostasis: improving intestinal calcium absorption (using calcium supplementation, vitamin D and derivates) and avoiding increased urinary calcium loss (using thiazides) prevent or counteract a secondary hyperparthyroidism. Bisphosphonates, particularly the aminobisphosphonates risedronate and alendronate, have been shown to protect patients on GCs from (further) bone loss to reduce vertebral fracture risk. Calcitonin may be of interest in situation where bisphosphonates are contraindicated or not applicable and in cases where acute pain due to vertebral fracture has to be manage. The intermittent administration of 1-34-parathormone may be an appealing treatment alternative, based on its documented anabolic effects on bone resulting from the reduction of osteoblastic apoptosis. Calcium and vitamin D should be a systematic adjunctive measure to any drug treatment for GIOP. Based on currently available evidence, fluoride, androgens, estrogens (opposed or unopposed) cannot be recommended for the prevention and treatment of GIOP. However, substitution of gonadal hormones may be indicated if GC-induced hypogonadism is present and leads to clinical symptoms. Data using the SERM raloxifene to treat or prevent GIOP are lacking, as are data using the promising bone anabolic agent strontium ranelate. Kyphoplasty performed in appropriately selected osteoporotic patients with painful vertebral fractures is a promising addition to current medical treatment.
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This third part of a series of publications from the Swiss task force "Smoking--Intervention in the private dental office" on the topic "tobacco use and dental medicine" describes the clinical and radiographic changes of the periodontium within smokers as well as the consequences of tobacco use on periodontal and implant therapy. With increased use of tobacco, patients show higher periodontal probing depths, increased clinical attachment loss, more alveolar bone resorption, a higher prevalence of gingival recessions, and a higher risk for tooth loss. In contrast to this, with smokers, the clinical characteristics of gingival inflammation or bleeding on periodontal probing are less established. Smokers show less positive results after conventional, surgical and regenerative periodontal therapy. The benefits of mucogingval surgery are reduced and less successful in smokers. Moreover, smoking impairs the osseointegration of oral implants and is at least partly responsible for a majority of biological complications in implant dentistry, such as periimplantitis. Based on the present understanding of periodontal diseases, the clinical findings, and the specific therapeutic outcomes with smokers, it appears to be reasonable, next to the current classification of periodontal diseases, to use the term "smokers periodontitis".
Resumo:
This literature review represents the second in a series of articles from the Swiss task force "Smoking--Intervention in the private dental office" on the topic "tobacco use and dental medicine". In this article, the epidemiological background as well as some pathogenetic processes are described and discussed critically for tobacco-related periodontal diseases. Earlier publications confirmed tobacco consumption as a risk factor for periodontal diseases. Over the last few years, oral health research has significantly contributed to the understanding of the mechanisms leading to the deterioration of the hard and soft tissues supporting the teeth. With the recording of the number of cigarettes smoked per day and the amount of years tobacco was used, a dose response relationship was established. Various, potentially significant pathogenic effects of tobacco-related substances may exist on the periodontal tissues, the immune response system or the composition of the oral flora. Moreover, there is reference that tobacco consumption may change the genetically determined susceptibility for periodontal diseases.
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OBJECTIVES: This study was designed to evaluate the effect of gap width and graft placement on bone healing around implants placed in simulated extraction sockets of various widths in four Labrador dogs. MATERIALS AND METHODS: Five Osseotite implants per dog were placed in the mandible of four dogs. Two implants were inserted into sites with a 2.37 mm and two with a 1 mm gap present between the implants and bone around the coronal 6 mm of the implants in each dog. For one of each gap sizes, the gap was filled with Bio-Oss, and the other two with blood alone. A fifth implant was inserted without a gap and used as a control. Ground sections were prepared from biopsies taken at 4 months and histometric measurements of osseointegration and bone between the threads made for the coronal 6 mm. RESULTS: The medians for osseointegration ranged from 5.2 mm for control to 1-2.6 mm for the test modalities. There were significant differences for linear measurements of osseointegration (chi(2) 18.27; df 4; P=0.0011) and bone area within threads (chi(2) 23.4; df 4; P=0.0001) between test modalities. CONCLUSIONS: The results suggest that the wider the gap around the implants, the less favourable the histological outcome at short time intervals following treatment. They also infer that bone grafting with an organic bovine bone xenograft seems to lead to a more favourable histological outcome for wider circumferential defects but not for narrower defects.
Resumo:
The Hungry Bone Syndrome (HBS) represents an important cause of prolonged hypocalcemia after parathyreoidectomy (PTX) due to primary, secondary or tertiary hyperparathyreoidism. The sudden postoperative withdrawal of parathyroid hormone (PTH) induces a stop in osteoclastic bone resorption without affecting the osteoblastic activity. Consequently, an increased bone uptake of calcium, phosphate and magnesium is observed. Risk factors for the development of HBS include: Large parathyroid adenomas, age > 60 years, high preoperative levels of serum PTH, calcium and alkaline phosphatase. In these patients a careful monitoring of clinical symptoms of hypocalcemia as well as the laboratory parameters are warranted during the immediate postoperative period. Treatment with oral calcium, and especially in patients with renal failure, additionally active vitamin D should be started as soon as possible after PTX. In severe cases of HBS, the administration of intravenous calcium is necessary. The duration of therapy is governed by symptoms and severity of the HBS and may last for up to 12 or more months. While prevention of HBS in high risk patients includes preoperative Vitamin D, the role of bisphosphonates has yet to be established.