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81.
Palliative management of brain metastases   总被引:1,自引:0,他引:1  
 The development of brain metastases in patients with advanced cancer is associated with increased morbidity and diminished longevity. Palliative treatment modalities focus predominantly on improving quality of life. Well-established beneficial treatments include the use of corticosteroids, radiotherapy, and surgery. Management issues that require further exploration and clarification include the dosages of glucocorticoids, the prophylactic use of anticonvulsants and the indications for radiosurgery.  相似文献   
82.
Propofol infusion syndrome (PRIS) is a rare and often fatal syndrome described in critically ill children undergoing long-term propofol infusion at high doses. Recently several cases have been reported in adults, too. The main features of the syndrome consist of cardiac failure, rhabdomyolysis, severe metabolic acidosis and renal failure. To date 21 paediatric cases and 14 adult cases have been described. These latter were mostly patients with acute neurological illnesses or acute inflammatory diseases complicated by severe infections or even sepsis, and receiving catecholamines and/or steroids in addition to propofol. Central nervous system activation with production of catecholamines and glucocorticoids, and systemic inflammation with cytokine production are priming factors for cardiac and peripheral muscle dysfunction. High-dose propofol, but also supportive treatments with catecholamines and corticosteroids, act as triggering factors. At the subcellular level, propofol impairs free fatty acid utilisation and mitochondrial activity. Imbalance between energy demand and utilisation is a key pathogenetic mechanism, which may lead to cardiac and peripheral muscle necrosis.Propofol infusion syndrome is multifactorial, and propofol, particularly when combined with catecholamines and/or steroids, acts as a triggering factor. The syndrome can be lethal and we suggest caution when using prolonged (>48 h) propofol sedation at doses higher than 5 mg/kg per h, particularly in patients with acute neurological or inflammatory illnesses. In these cases, alternative sedative agents should be considered. If unsuitable, strict monitoring of signs of myocytolysis is advisable.  相似文献   
83.
Objective To determine incidence, risk factors and impact on various outcome parameters of the development of acute quadriplegic myopathy in a selected population of critically ill patients.Setting A prospective cohort study carried out in the intensive care unit of a tertiary-level university hospital.Patients All patients admitted due to acute exacerbation of chronic obstructive pulmonary disease who required intubation and mechanical ventilation, and received high doses of intravenous corticosteroids.Interventions A neurophysiological study was performed in all cases at the onset of weaning. Muscular biopsy was taken when the neurophysiological study revealed a myopathic pattern.Measurements and results Twenty-six patients were enrolled in the study. Nine patients (34.6%) developed myopathy. Only seven patients were treated with muscle relaxants. Histology confirmed the diagnosis in the three patients who underwent muscle biopsy. APACHE II score at admission, the rate of sepsis and the total doses of corticosteroids were significantly higher in patients with myopathy compared with those patients that did not develop it. Myopathy is associated with an increase in the duration of mechanical ventilation [15.4 (9.2) versus 5.7 (3.9) days; p<0.006], the length of ICU stay [23.6 (10.7) versus 11.4 (7.05) days; p<0.003] and hospital stay [33.3 (19.2) versus 21.2 (16.1) days; p<0.034)]. Myopathy was not associated with increased mortality.Conclusions In the population under study, severity of illness at admission, the development of sepsis and the total dose of corticosteroids are factors associated with the occurrence of myopathy after the administration of corticosteroids. Myopathy was associated with prolonged mechanical ventilation and in-hospital stay.  相似文献   
84.
Cyclosporine (CyA) has an immunosuppressive effect that might suggest a therapeutic role in idiopathic glomerular conditions. We focused on the optimization of CyA treatment control in patients with idiopathic nephrotic syndrome by using trough‐level CyA measurements (C0) and the 2‐h postdose levels (C2). Twenty‐two patients (14 male, 8 female) with idiopathic nephrotic syndrome and the mean age of 51 ± 18 months (mean [M] ± standard deviation [SD]) were enrolled in our study during a period of 10 months (range: 3–18 months). All of the patients received CyA (2–3 mg/kg) in combination with methylprednisolone. In the present study protocol CyA concentrations (C0, C2), renal function, lipid profile, and degree of proteinuria were determined. The mean proteinuria of our patients before treatment was 11 972 ± 7953 mg/24 H (±SD) and the mean creatinine level (Cr) was 0.99 ± 0.37 mg/dL (±SD). Proteinuria decreased significantly already from the first month of therapy with CyA to 3578 ± 2470 mg/24 H (M± SD), and during the whole study period this reduction was significant (0.56 ± 0.37 gr/24 H (M ± SD), P < 0.05). At the same time renal function preserved, 1.09 ± 0.48 mg/dL (M ± SD). The blood levels of C0 were 135.10 ± 97.36 ng/mL (M ± SD) and the blood levels of C2 were 725 ± 256 ng/mL (M ± SD) at the first month of therapy. At the same time renal function preserved, 1.09 ± 0.48 mg/dL (M ± SD). Total cholesterol levels reduced significantly during study period (276.89 ± 45.57 to 200.67 ± 40.27 mg/dL [M ± SD]). The mean number of antihypertensive medication remained the same. The whole therapeutic protocol did not provoke any kind of side effects and CyA was quite tolerated by our patients. Treatment of idiopathic nephrotic syndrome with low doses of CyA with methylprednisolone leads to remission of proteinuria without deterioration of renal function. Blood levels of C0 for monitoring and treatment of nephrotic syndrome agrees with recent literature, while our study focus on establishing the proper levels of C2 for the treatment of nephrotic syndrome. The efficacy of CyA is combined with safety and tolerance.  相似文献   
85.
Background Ulcerative colitis is characterized by relapsing mucosal inflammation where the lesions include tissue-damaging granulocytes. In addition, T cells and natural killer (NK) cells play important pathophysiologic roles. Chemokines are a large family of peptides that play key roles in the regulation of inflammation. The CXC-chemokines, growth-related oncogene (GRO)-α/CXCL1 and interleukin (IL)-8/CXCL8, both recruit neutrophils and possess mitogenic properties, whereas the interferon-dependent CXC-chemokines monokine induced by gamma-interferon (MIG)/CXCL9, interferon-γ inducible protein of 10 kD/CXCL10, and IFN-inducible T cell alpha chemoattractant/CXCL11 recruit and activate T cells and NK cells. Materials and methods The expression of CXC-chemokines was studied in eight controls and in 11 patients suffering from ulcerative colitis in the distal part of the colon, before and during topical treatment with corticosteroids. Perfusates (obtained before, after 7 days, and after 28 days of treatment) and pinch biopsies (obtained before and after 28 days of treatment) were collected by colonoscopy. The rectal release of GRO-α and MIG was determined by enzyme-linked immunosorbent assay (ELISA), and tissue expression of the chemokines was detected in colonic tissue by immunohistochemistry. Results In perfusates, high levels of GRO-α, IL-8, and MIG were detected compared with controls (p = 0.02, 0.005, and p = 0.03, respectively). During treatment with corticosteroids, both GRO-α and MIG decreased. In clinical nonresponders, characterized by sustained inflammation, the levels of GRO-α and MIG remained elevated. Both epithelial cells and granulocytes, present in the submucosa, expressed GRO-α and MIG as detected by immunohistochemistry. Conclusions CXC-chemokines are likely to be important in the pathophysiology of ulcerative colitis and may become targets for novel treatment strategies. In addition, GRO-α may serve as a marker of disease activity.  相似文献   
86.
Live to the rhythm, slave to the rhythm   总被引:1,自引:0,他引:1  
Circadian rhythms in health and disease have most often been described in terms of their phases and amplitudes, and how these respond to a single exposure to stimuli denoted as zeitgebers. The present paper argues that it is also important to consider the 24-h regularity in the repeated occurrence of the zeitgebers. The effect of the regularity of stimulation by light, melatonin, physical activity, body temperature, corticosteroids and feeding on synchronization within and between the central circadian clock and peripheral oscillators is discussed. In contrast to the phase shifts that can be recorded acutely after a single zeitgeber pulse, the effects of irregularly versus regularly timed zeitgeber can be studied only in long-term protocols and may develop slowly, which is a possible reason why they have received relatively little attention. Several observations indicate a reciprocal relation between the robustness of the endogenous circadian timing system and its dependency on regularly timed zeitgebers. Especially at old age and in disease, proper functioning of the circadian timing system may become more dependent on regularly timed exposure to zeitgeber stimuli. in such conditions, regularly timed exposure to zeitgeber appears to be highly important for health. After a concise introduction on inputs to the central and peripheral oscillators of the circadian timing system, the paper discusses the responses of the circadian timing system and health to (1) a chronic lack of zeitgeber stimuli; (2) fragmented or quasi-ultradian stimuli and (3) repeated phase shifts in stimuli. Subsequently, the specific relevance to aging is discussed, followed by an overview of the effects of experimentally imposed regularly timed stimuli. Finally, a possible mechanism for the gradually evolving effects of repeated regularly timed stimuli on the circadian timing system is proposed.  相似文献   
87.
The effect of dexamethasone on the transmesothelial electrical resistance (R TM) of sheep pleura was investigated by Ussing chamber experiments. Our results show that dexamethasone decreases the R TM of sheep pleurae, in part by stimulation of glucocorticoid receptors. This finding may be of importance in regard to the faster resolution of corticosteroid-treated pleural effusions.  相似文献   
88.
Dengue infection results in significant morbidity and mortality worldwide. Current recommended treatment is largely supportive with careful fluid replacement, with no specific treatment available. Although corticosteroids are not mentioned in the WHO guidelines on the management of dengue, clinicians use corticosteroids empirically based on the presumed immunological basis of the complications of dengue. The evidence base for the benefit or lack of benefit of corticosteroids in dengue is limited; previous studies have been small, with methodological flaws, less stringent randomisation and unclear allocation concealment, and were performed a long time ago. Studies so far have only been in patients with shock syndrome, and the possible effects of corticosteroids on thrombocytopenia and bleeding as well as other complications of dengue are unknown. All previous studies have been in children; the effect of corticosteroid treatment in adults with dengue infection has not been evaluated. The possible beneficial effects of corticosteroids on the various manifestations of dengue infection need evaluation by adequately powered, well designed, randomised controlled trials.  相似文献   
89.
This review concentrates on autoimmune hepatitis (AIH), a liver disorder affecting both children and adults, characterized by inflammatory liver histology, elevated transaminase levels, circulating non-organ-specific autoantibodies, and increased levels of immunoglobulin G, in the absence of a known aetiology. Two types of AIH are recognized according to seropositivity: smooth muscle antibody and/or antinuclear antibody define AIH type 1, while antibodies to liver-kidney microsome type 1 and/or liver cytosol type 1 define AIH type 2. AIH type 1 affects both adults and children, while AIH type 2 is mainly a paediatric disease, though it does occasionally affects young adults. There is a female predominance in both types. AIH is particularly aggressive in children/adolescents, progressing rapidly unless immunosuppressive treatment is started promptly. With appropriate treatment 80% of patients achieve remission and long-term survival. In childhood/adolescence, sclerosing cholangitis with strong autoimmune features, including interface hepatitis and serological features identical to AIH type 1, is as prevalent as AIH, but it affects boys and girls equally. The differential diagnosis relies on cholangiographic studies. In autoimmune sclerosing cholangitis, liver parenchymal damage responds satisfactorily to immunosuppressive treatment, whereas bile duct disease progresses in 50% of cases, leading to a worse prognosis and higher transplantation requirement; it has a higher recurrence rate after transplant than AIH. AIH can arise de novo in patients transplanted for non-autoimmune liver disease. Post transplant de novo AIH affects children and adults and responds well to the same treatment schedule used for classical AIH, but not to that used for acute rejection.  相似文献   
90.
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