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The purpose of the work was to set‐up a simple method to evaluate the contribution of Mn2+ ions in the intra‐ and extracellular tumor compartments in a MEMRI experiment. This task has been tackled by “silencing” the relaxation enhancement arising from Mn2+ ions in the extracellular space. In vitro relaxometric measurements allowed assessment of the sequestering activity of DO2A (1,4,7,10‐tetraazacyclododecane‐1,7‐diacetic acid) towards Mn2+ ions, as the addition of Ca‐DO2A to a solution of MnCl2 causes a drop of relaxivity upon the formation of the highly stable and low‐relaxivity Mn‐DO2A. It has been proved that the sequestering ability of DO2A towards Mn2+ ions is also fully effective in the presence of serum albumin. Moreover, it has been shown that Mn‐DO2A does not enter cell membranes, nor does the presence of Ca‐DO2A in the extracellular space prompt migration of Mn ions from the intracellular compartment. On this basis the in vivo, instantaneous, drop in SE% (percent signal enhancement) in T1‐weighted images is taken as evidence of the sequestration of extracellular Mn2+ ions upon addition of Ca‐DO2A. By applying the method to B16F10 tumor bearing mice, T1 decrease is readily detected in the tumor region, whereas a negligible change in SE% is observed in kidneys, liver and muscle. The relaxometric MRI results have been validated by ICP‐MS measurements. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
3.
Background: Mitochondrial adenosine triphosphate-sensitive potassium (mitoKATP) channels play a pivotal role in mediating cardiac preconditioning. The effects of intravenous anesthetics on this protective channel have not been investigated so far, but would be of importance with respect to experimental as well as clinical medicine.

Methods: Live cell microscopy was used to visualize and measure autofluorescence of flavoproteins, a direct reporter of mitoKATP channel activity, in response to the direct and highly selective mitoKATP channel opener diazoxide, or to diazoxide following exposure to various anesthetics commonly used in experimental and clinical medicine. A cellular model of ischemia with subsequent hypoosmolar trypan blue staining served to substantiate the effects of the anesthetics on mitoKATP channels with respect to myocyte viability.

Results: Diazoxide-induced mitoKATP channel opening was significantly inhibited by the anesthetics R-ketamine, and the barbiturates thiopental and pentobarbital. Conversely, urethane, 2,2,2-trichloroethanol (main metabolite of [alpha]-chloralose and chloral hydrate), and the opioid fentanyl potentiated the channel-opening effect of diazoxide, which was abrogated by coadministration of chelerythrine, a specific protein kinase C inhibitor. S-ketamine, propofol, xylazine, midazolam, and etomidate did not affect mitoKATP channel activity. The significance of these modulatory effects of the anesthetics on mitoKATP channel activity was substantiated in a cellular model of simulated ischemia, where diazoxide-induced cell protection was mitigated by R-ketamine and the barbiturates, while urethane, 2,2,2-trichloroethanol, and fentanyl potentiated myocyte protection.  相似文献   

4.
Psoriasis is a chronic inflammatory condition that often requires life-long treatment. Conventional therapies have not fully met the needs of psoriatic patients, because of limited efficacy, adverse effects with cumulative use, and patient inconvenience. In the past decade, biologic immunotherapies have become accepted treatments for psoriasis as a result of perceived efficacy and safety on the part of patients and practitioners. However, most data on these medications come from relatively limited short-term trials. In this review, we will focus on the available long-term data on the efficacy of the biologic agents. We will emphasize the strengths and weakness of the available data of the biologic agents that are Food and Drug Administration (FDA)-approved for the treatment of moderate to severe psoriasis (alefacept, efalizumab, * etanercept, infliximab, and adalimumab), with the inclusion of a newer agent currently under FDA evaluation (ustekinumab).  相似文献   
5.
Background: Neuraxial blockade is used as primary anesthetic technique in one third of surgical procedures. The authors tested whether bisoprolol would protect patients at risk for cardiovascular complications undergoing surgery with spinal block.

Methods: The authors performed a double-blinded, placebo-controlled, multicenter trial to compare the effect of bisoprolol with that of placebo on 1-yr composite outcome including cardiovascular mortality, nonfatal myocardial infarction, unstable angina, congestive heart failure, and cerebrovascular insult. Bisoprolol was given orally before and after surgery for a maximum of 10 days. Adrenergic receptor polymorphisms and safety outcome measures of bisoprolol therapy were also determined.

Results: A total of 224 patients were enrolled. Spinal block could not be established in 5 patients. One hundred ten patients were assigned to the bisoprolol group, and 109 patients were assigned to the placebo group. The mean duration of treatment was 4.9 days in the bisoprolol group and 5.1 days in the placebo group. Bisoprolol therapy reduced mean heart rate by 10 beats/min. The primary outcome was identical between treatment groups and occurred in 25 patients (22.7%) in the bisoprolol group and 24 patients (22.0%) in the placebo group during the 1-yr follow-up (hazard ratio, 0.97; 95% confidence interval, 0.55-1.69; P = 0.90). However, carriers of at least one Gly allele of the [beta]1-adrenergic receptor polymorphism Arg389Gly showed a higher number of adverse events than Arg homozygous (32.4% vs. 18.7%; hazard ratio, 1.87; 95% confidence interval, 1.04-3.35; P = 0.04).  相似文献   

6.
Poverty, health services, and health status in rural America   总被引:5,自引:0,他引:5  
Access to health services for everyone has been a major policy goal in the United States: inequitable access is assumed to lead to inequitable health status, particularly for low-income groups. A sophisticated model of the relation between poverty, health care needs, service use, and health outcomes is used to analyze cross-sectional data on 7,823 adults from 36 rural communities. Improved access and use are helpful, but evidence clearly indicates that combined health and social initiatives will be necessary to reduce inequalities in health status.  相似文献   
7.
Deletions of 17p and p53 mutations in preneoplastic lesions of the lung.   总被引:17,自引:0,他引:17  
Cytogenetic and p53 mutation analysis in two cases of severe dysplasia of the bronchial epithelium in lung cancer patients and p53 immunostaining in a third one are reported. The finding of both chromosomal deletions of 17p and p53 mutation indicates that these changes may take place early in the process of lung carcinogenesis.  相似文献   
8.
The European Society of Thoracic Surgeons (ESTS) organized a workshop dealing with lymph node staging in non-small cell lung cancer. The objective of this workshop was to develop guidelines for definitions and the surgical procedures of intraoperative lymph node staging, and the pathologic evaluation of resected lymph nodes in patients with non-small cell lung cancer (NSCLC). Relevant peer-reviewed publications on the subjects, the experience of the participants, and the opinion of the ESTS members contributing on line, were used to reach a consensus. Systematic nodal dissection is recommended in all cases to ensure complete resection. Lobe-specific systematic nodal dissection is acceptable for peripheral squamous T1 tumors, if hilar and interlobar nodes are negative on frozen section studies; it implies removal of, at least, three hilar and interlobar nodes and three mediastinal nodes from three stations in which the subcarinal is always included. Selected lymph node biopsies and sampling are justified to prove nodal involvement when resection is not possible. Pathologic evaluation includes all lymph nodes resected separately and those remaining in the lung specimen. Sections are done at the site of gross abnormalities. If macroscopic inspection does not detect any abnormal site, 2-mm slices of the nodes in the longitudinal plane are recommended. Routine search for micrometastases or isolated tumor cells in hematoxylin-eosin negative nodes would be desirable. Randomized controlled trials to evaluate adjuvant therapies for patients with these conditions are recommended. The adherence to these guidelines will standardize the intraoperative lymph node staging and pathologic evaluation, and improve pathologic staging, which will help decide on the best adjuvant therapy.  相似文献   
9.
The aim of this study is to establish whether a preoperative evaluation of the Cerebral Hemodynamic Reserve, carried out by means of transcranial Doppler and SPECT with provocative test (acetazolamide) can single out those patients who, because they are supplied with a poor cerebral reserve, are truly in need of intraoperative shunting after carotid clamping. All patients were intraoperatively monitored by means of Somato Sensitive Evoked Potentials (SSEPs). Those patients who were shunted due to abnormalities in SSEPs were also those who showed a perfusion and velocity increase below 15%, and therefore supplied, in our opinion, with a scanty cerebral reserve. No, but one, neurological deficit appeared on awakening in patients who were not shunted.  相似文献   
10.
A retrospective survey was carried out in a group of 39 previously obese and hypertensive subjects to evaluate: the rate of blood pressure reductions achieved by dietary treatment, the smallest weight reduction accompanied by a significant decrease in blood pressure, and the mean weight reduction associated with normalization of pressure. Significant decrease in weight, systolic and diastolic pressures were observed after 15 days of treatment in 21 patients who had never assumed antihypertensive drugs and 9 who were on medication. Blood pressure normalization was achieved in 19 of the former with a weight reduction of 7.63 +/- 4.29% kg and in 7 of the latter after losing 8.63 +/- 2.20% kg; in 3 patients the medication was reduced and in 1 was withdrawn. In 4 patients weight but not pressure had decreased and in 5 neither did. Reduction, often normalization, of blood pressure can be obtained through relatively minor weight loss in most obese hypertensive patients.  相似文献   
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