957 resultados para 640300 First Stage Treatment of Ores and Minerals
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Multiple sclerosis (MS) is a life-long, potentially debilitating disease of the central nervous system (CNS). MS is considered to be an immune-mediated disease, and the presence of autoreactive peripheral lymphocytes in CNS compartments is believed to be critical in the process of demyelination and tissue damage in MS. Although MS is not currently a curable disease, several disease-modifying therapies (DMTs) are now available, or are in development. These DMTs are all thought to primarily suppress autoimmune activity within the CNS. Each therapy has its own mechanism of action (MoA) and, as a consequence, each has a different efficacy and safety profile. Neurologists can now select therapies on a more individual, patient-tailored basis, with the aim of maximizing potential for long-term efficacy without interruptions in treatment. The MoA and clinical profile of MS therapies are important considerations when making that choice or when switching therapies due to suboptimal disease response. This article therefore reviews the known and putative immunological MoAs alongside a summary of the clinical profile of therapies approved for relapsing forms of MS, and those in late-stage development, based on published data from pivotal randomized, controlled trials.
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Purpose of review Tyrosine kinase inhibitors (TKIs), such as imatinib and sunitinib, have changed the outcome of patients with gastrointestinal stromal tumor (GIST) and prolonged survival by many-fold. Unfortunately, treatment failure and tumor progression seem inevitable over time and constitute an unresolved clinical challenge. This article reviews current efforts to overcome drug resistance and progression. Recent findings The major mechanism of resistance toward imatinib and sunitinib is the development of secondary resistance mutations in the kinase domain of KIT. Recent efforts aim at inhibitors with increased activity against resistance mutations or a broader spectrum of activity. Other strategies include indirect KIT inhibition by modulating KIT chaperone proteins or inhibition of KIT-dependent and independent signaling pathways. Summary dThe rapid improvement of our understanding of GIST biology as well as resistance mechanisms towards imatinib and sunitinib will greatly facilitate the development of novel treatment strategies. This article summarizes the results of recently reported third and fourth-line clinical trials in patients with resistant GIST and reviews data of important proof-of-concept studies.
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This study was designed to evaluate the effectiveness of zinc sulphate both in vitro and in an animal model against both strains of old world cutaneous leishmaniasis. The in vitro sensitivities of promastigotes and axenic amastigotes of both Leishmania major and L. tropica to zinc sulphate was determined, the LD50 calculated and compared to the standard treatment for cutaneous leishmaniasis pentavalent antimony compounds. The results show that the two forms of both strains were sensitive to zinc sulphate and their respective LD50 were lower compared to the pentavalent antimony compound. Furthermore the sensitivities of the forms of both strains were tested using a simple slide method and compared to results of the standard method. To confirm this result, zinc sulphate was administered orally to mice infected with cutaneous leishmaniasis both therapeutically and prophylactically. Results showed that oral zinc sulphate was effective in both treatment and prophylaxis for cutaneous leishmaniasis. These results encourage the use of oral zinc sulphate in the treatment of cutaneous leishmaniasis clinically.
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BACKGROUND: Both non-traumatic and traumatic spinal cord injuries have in common that a relatively minor structural lesion can cause profound sensorimotor and autonomous dysfunction. Besides treating the cause of the spinal cord injury the main goal is to restore lost function as far as possible. AIM: This article provides an overview of current innovative diagnostic (imaging) and therapeutic approaches (neurorehabilitation and neuroregeneration) aiming for recovery of function after non-traumatic and traumatic spinal cord injuries. MATERIAL AND METHODS: An analysis of the current scientific literature regarding imaging, rehabilitation and rehabilitation strategies in spinal cord disease was carried out. RESULTS: Novel magnetic resonance imaging (MRI) based techniques (e.g. diffusion-weighted MRI and functional MRI) allow visualization of structural reorganization and specific neural activity in the spinal cord. Robotics-driven rehabilitative measures provide training of sensorimotor function in a targeted fashion, which can even be continued in the homecare setting. From a preclinical point of view, defined stem cell transplantation approaches allow for the first time robust structural repair of the injured spinal cord. CONCLUSION: Besides well-established neurological and functional scores, MRI techniques offer the unique opportunity to provide robust and reliable "biomarkers" for restorative therapeutic interventions. Function-oriented robotics-based rehabilitative interventions alone or in combination with stem cell based therapies represent promising approaches to achieve substantial functional recovery, which go beyond current rehabilitative treatment efforts.
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BACKGROUND: Refractory status epilepticus (RSE) has a mortality of 16-39%; coma induction is advocated for its management, but no comparative study has been performed. We aimed to assess the effectiveness (RSE control, adverse events) of the first course of propofol versus barbiturates in the treatment of RSE. METHODS: In this randomized, single blind, multi-center trial studying adults with RSE not due to cerebral anoxia, medications were titrated toward EEG burst-suppression for 36-48 h and then progressively weaned. The primary endpoint was the proportion of patients with RSE controlled after a first course of study medication; secondary endpoints included tolerability measures. RESULTS: The trial was terminated after 3 years, with only 24 patients recruited of the 150 needed; 14 subjects received propofol, 9 barbiturates. The primary endpoint was reached in 43% in the propofol versus 22% in the barbiturates arm (P = 0.40). Mortality (43 vs. 34%; P = 1.00) and return to baseline clinical conditions at 3 months (36 vs. 44%; P = 1.00) were similar. While infections and arterial hypotension did not differ between groups, barbiturate use was associated with a significantly longer mechanical ventilation (P = 0.03). A non-fatal propofol infusion syndrome was detected in one patient, while one subject died of bowel ischemia after barbiturates. DISCUSSION: Although undersampled, this trial shows significantly longer mechanical ventilation with barbiturates and the occurrence of severe treatment-related complications in both arms. We describe practical issues necessary for the success of future studies needed to improve the current unsatisfactory state of evidence.
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Epidermal and dermal cells can be multiplied in vitro using different techniques. Under particular conditions, the structure and the function of the original tissues are partly recreated. Autologous epidermal substitutes for wound coverage in deep burns are prepared in less than three weeks. Bilayered skin equivalents containing a dermal component are obtained by growing epidermal cells on a reconstructed dermal substitute or by juxtaposing stratified cultures of keratinocytes and fibroblasts. New technologies are required to optimise the nutrition of three-dimensional cultures of skin cells, which should lead to further progress in the area of skin reconstruction.
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Fabry disease is caused by a deficiency of a-galactosidase A which leads to the progressive intra-lysosomal accumulation of ceramide trihexoside (CTH), also known as globotriaosylceramide (Gb3), in different cell types and body fluids. The clinical manifestations are multisystemic and predominantly affect the heart, kidney and central nervous system. The role of CTH in the pathophysiological process of Fabry disease is not established, and the link between the degree of accumulation and disease manifestations is not systematic. The use of CTH as a diagnostic tool has been proposed for several decades. The recent introduction of a specific treatment for Fabry disease in the form of enzyme replacement therapy (ERT) has led to the need for a biological marker, in place of a clinical sign, for evaluating the efficacy of treatment and also as a tool for following the long term effects of treatment. The ideal biomarker must adhere to strict criteria, and there should be a correlation between the degree of clinical efficacy of treatment and a change in its concentration. This review of the literature assesses the utility of CTH as a diagnostic tool and as a marker of the efficacy of ERT in patients with Fabry disease. Several techniques have been developed for measuring CTH; the principles and the sensitivity thresholds of these methods and the units used to express the results should be taken into consideration when interpreting data. The use of CTH measurement in Fabry disease should be re-evaluated in light of recent published data.
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The treatment of hip osteoarthritis with total hip arthroplasty has continuously evolved since it was first introduced in the sixties. The problem of aseptic loosening of the cemented prostheses, mainly in young active patients, has stimulated two different types of research: on one side the improvement of cementing techniques and on the other side the development of cementless osteoinegrable implants. We discuss the problems of these cementless hip prostheses. Recently published anatomic and biomechanic studies have led to the development of personalized custom femoral stems for each patient. The conception technique and first clinical results are described.
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Aedes albifasciatus is a floodwater mosquito that breeds in temporary waters. This semi-domestic species, widely distributed in Argentina, is a competent vector of the western equine encephalitis. The present study was carried out in two rain pools of the city of Buenos Aires, from April 1998 through March 1999. Samples were taken twice a week during the cold season and daily during the warmer months, starting from October. Immature mosquitoes were collected with a dipper, being the number of dippers proportional to the flooded area. The estimated rainfall thresholds to initiate cohorts of Ae. albifasciatus were: 16-17 mm in the fall-winter period, 25 mm in the spring, and 30 mm in the summer. The development time of the different cohorts and the mean air temperature of their respective periods were estimated in all seasons, ranging from six days (at 24ºC) to 32 days (at 13ºC). The equation that best expresses the relationship between development time and mean air temperature is dt =166,27.e-0,1435.T (R²=0,92). Significantly shorter development times were recorded for larvae of the first three stages as compared to the fourth larval stage and pupae.
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BACKGROUND: To evaluate the safety and clinical feasibility of focal irreversible electroporation (IRE) of the prostate. METHODS: We assessed the toxicity profile and functional outcomes of consecutive patients undergoing focal IRE for localised prostate cancer in two centres. Eligibility was assessed by multi-parametric magnetic resonance imaging (mpMRI) and targeted and/or template biopsy. IRE was delivered under transrectal ultrasound guidance with two to six electrodes positioned transperineally within the cancer lesion. Complications were recorded and scored accordingly to the NCI Common Terminology Criteria for Adverse Events; the functional outcome was physician reported in all patients with at least 6 months follow-up. A contrast-enhanced MRI 1 week after the procedure was carried out to assess treatment effect with a further mpMRI at 6 months to rule out evidence of residual visible cancer. RESULTS: Overall, 34 patients with a mean age of 65 years (s.d.=±6) and a median PSA of 6.1 ng ml(-1) (interquartile range (IQR)= 4.3-7.7) were included. Nine (26%), 24 (71%) and 1 (3%) men had low, intermediate and high risk disease, respectively (D'Amico criteria). After a median follow-up of 6 months (range 1-24), 12 grade 1 and 10 grade 2 complications occurred. No patient had grade >/= 3 complication. From a functional point of view, 100% (24/24) patients were continent and potency was preserved in 95% (19/20) men potent before treatment. The volume of ablation was a median 12 ml (IQR=5.6-14.5 ml) with the median PSA after 6 months of 3.4 ng ml(-1) (IQR=1.9-4.8 ng ml(-1)). MpMRI showed suspicious residual disease in six patients, of whom four (17%) underwent another form of local treatment. CONCLUSIONS: Focal IRE has a low toxicity profile with encouraging genito-urinary functional outcomes. Further prospective development studies are needed to confirm the functional outcomes and to explore the oncological potential.
Treatment of chronic hepatitis C genotype 1 with triple therapy comprising telaprevir or boceprevir.
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Hepatitis C virus (HCV) infection is a leading cause of chronic hepatitis, liver cirrhosis and hepatocellular carcinoma worldwide. Two first-generation protease inhibitors, telaprevir and boceprevir, have recently been approved for the treatment of chronic hepatitis C genotype 1. Triple therapy comprising pegylated interferon-α, ribavirin and telaprevir or boceprevir increases sustained virological response rates to ~70% and allows to shorten treatment duration in ~½ of treatment-naïve patients with chronic hepatitis C genotype 1. Sustained virological response rates in treatment-experienced patients depend on the response to previous treatment, ranging from >80% in previous relapsers to ~30% in previous null responders. These advances come at the expense of new adverse effects and increased cost. In addition, treatment of chronic hepatitis C will become more complex. In these times of changing medical practice, the present expert opinion statement by the Swiss Association for the Study of the Liver shall provide guidance on the treatment of chronic hepatitis C with triple therapy comprising telaprevir or boceprevir.
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Census of Drug and Alcohol Treatment Services in Northern Ireland: 1 March 2005