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51.
The aim of this study was to evaluate the effect of a low-saturated-fat, low-cholesterol diet on plasma lipopoproteins, pre beta-high density lipoprotein (HDL) formation, lecithin:cholesterol acyltransferase (LCAT), cholesteryl ester transfer protein (CETP) and phospholipid transfer protein (PLTP) activities, as well as on the ability of plasma to stimulate cellular cholesterol efflux. Twelve male type 1 diabetic patients with plasma cholesterol >5.0 mmol/L were studied while consuming their usual diet and after 6 weeks of a low-fat, low-cholesterol diet. Pre beta-HDL formation was measured using crossed immuno-electrophoresis. Plasma LCAT, CETP and PLTP activities were assayed by exogenous substrate methods. The ability of plasma to promote cellular cholesterol efflux out of Fu5AH rat hepatoma cells and out of human skin fibroblasts was also determined. Saturated fat intake was lowered (p = 0.001) due to replacement with carbohydrates, while mono- and polyunsaturated fat intake remained unchanged. Cholesterol intake decreased as well (p = 0.003). The changes in plasma total cholesterol, very low and low-density lipoprotein (VLDL+LDL) cholesterol, HDL cholesterol, HDL phospholipids, apolipoprotein (apo) A-I, plasma LCAT activity and PLTP activity were not significant. Plasma CETP activity (p = 0.008) and pre beta-HDL formation (p = 0.008) decreased. The ability of plasma to promote cholesterol efflux out of fibroblasts and Fu5AH cells remained unchanged. Reduction in dietary saturated fat and cholesterol intake does not adversely affect cellular cholesterol efflux to plasma from type 1 diabetic patients, despite a drop in pre beta-HDL formation.  相似文献   
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Simultaneously Manufactured Nano-In-Micro (SIMANIM) particles for the pulmonary delivery of antibodies have been prepared by the spray-drying of a double-emulsion containing human IgG (as a model antibody), lactose, poly(lactide-co-glycolide) (PLGA) and dipalmitoylphosphatidylcholine (DPPC). The one-step drying process involved producing microparticles of a diameter suitable for inhalation that upon contact with aqueous media, partially dissolved to form nanoparticles, ~10-fold smaller than their original diameter. Continuous release of the model antibody was observed for 35 days in pH 2.5 release media, and released antibody was shown to be stable and active by gel electrophoresis, field-flow fractionation and enzyme linked immunosorbent assay. Adding 1% L-leucine to the emulsion formulation, and blending ‘SIMANIM’ particles with 1% magnesium stearate, achieved a fine particle fraction of ~60%, when aerosolised from a simple, capsule-based, dry powder inhaler device. ‘SIMANIM’ particles could be beneficial for the delivery of antibodies targeted against inhaled pathogens or other extracellular antigens, as well as having potential applications in the delivery of a wide range of other biopharmaceuticals and certain small-molecule drugs. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:4055–4068, 2009  相似文献   
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Wall shear stress (WSS), the frictional force between blood and endothelium, is an important determinant of vascular function. It is generally assumed that WSS remains constant at a reference value of 15 dyn/cm(2). In a study of small rodents, we realized that this assumption could not be valid. This review presents an overview of recent studies in large and small animals where shear stress was measured, derived from velocity measurements or otherwise, in large vessels. The data show that large variations exist within a single species (human: variation of 2-16 N/m(2)). Moreover, when we compared different species at the same location within the arterial tree, an inverse relationship between animal size and wall shear stress was noted. When we related WSS to diameter, a unique relationship was derived for all species studied. This relationship could not be described by the well-known r(3) law of Murray, but by the r(2) law introduced by Zamir et al. in 1972. In summary, by comparing data from the literature, we have shown that: (i) the assumption of a physiological WSS level of approximately 15 dyn/cm(2) for all straight vessels in the arterial tree is incorrect; (ii) WSS is not constant throughout the vascular tree; (iii) WSS varies between species; (iv) WSS is inversely related to the vessel diameter. These data support an "r(2) law" rather than Murray's r(3) law for the larger vessels in the arterial tree.  相似文献   
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Background

Peripheral sensory neurotoxicity is a frequent and potentially debilitating side effect of oxaliplatin treatment. Calcium and magnesium (Ca/Mg) infusions are frequently used to prevent this toxicity. However, concerns about a negative impact of Ca/Mg infusions on outcome have been raised. We retrospectively assessed the effect of Ca/Mg infusions on the incidence of neurotoxicity and on clinical outcome in advanced colorectal cancer (ACC) patients treated in the phase III CAIRO2 study.

Materials and methods

Seven hundred and fifty five previously untreated ACC patients were randomised between treatment with capecitabine, oxaliplatin and bevacizumab or the same combination with the addition of cetuximab. Patients were retrospectively divided into two groups: patients in the Ca/Mg+ group received Ca/Mg at least during their first treatment cycle, and patients in the Ca/Mg- group did not.

Results

Seven hundred and thirty two patients were evaluable for this analysis. The Ca/Mg+ group consisted of 551 patients, the Ca/Mg- group consisted of 181 patients. The incidence of all grade neurotoxicity in the Ca/Mg+ group and the Ca/Mg- group was 85% and 92%, respectively (p = 0.02), and the incidence of grade ? 2 neurotoxicity was 40% and 45%, respectively (p = 0.22). The median PFS in the Ca/Mg+ versus Ca/Mg- group was 10.1 versus 10.7 months (p = 0.92), the median OS was 19.8 versus 20.7 months (p = 0.10), and the response rate was 43.1% versus 50% (p = 0.11), respectively.

Conclusions

In this largest retrospective analysis to date we observed that Ca/Mg infusions significantly reduced all grade oxaliplatin-related neurotoxicity. Ca/Mg infusions did not affect the clinical efficacy of treatment.  相似文献   
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This study reports on the use and evaluation of immunocytochemistry in diagnostic cytology by correlation with (immuno)histology. The cytologic material was collected during a period of 3 years. Sixty-four patients were selected and studied retrospectively. The reactivity of a number of polyclonal and monoclonal antibodies was investigated and applied to a diverse group of tumors. Marker expression on routine cytologic and histologic material was compared and the use of immunocytochemistry in diagnosis was evaluated. Immunocytochemistry proved to be an easy and valuable technique for the identification and classification of tumor cells, and there was a good concordance with immunohistology. A discrepancy in marker expression was found in 10% of the slides that were investigated. Immunocytochemistry led to a misdiagnosis in only four cases; however, in these cases cytology alone would not have led to the correct diagnosis. The causes for the discrepancies are discussed. It is estimated that immunocytochemistry contributed to the diagnosis of approximately 50% of the cases, supplying either additional or essential information. A wide variety of markers can be applied reliably on cytologic preparations. The use of panels of antibodies is mandatory.  相似文献   
59.
Dopamine receptor genes: new tools for molecular psychiatry.   总被引:3,自引:0,他引:3       下载免费PDF全文
For over a decade it has been generally assumed that all the pharmacological and biochemical actions of dopamine within the central nervous system and periphery were mediated by two distinct dopamine receptors. These receptors, termed D1 and D2, were defined as those coupled to the stimulation or inhibition of adenylate cyclase, respectively, and by their selectivity and avidity for various drugs and compounds. The concept that two dopamine receptors were sufficient to account for all the effects mediated by dopamine was an oversimplification. Recent molecular biological studies have identified five distinct genes which encode at least eight functional dopamine receptors. The members of the expanded dopamine receptor family, however, can still be codifed by way of the original D1 and D2 receptor dichotomy. These include two genes encoding dopamine D1-like receptors (D1 [D1A]/D5 [D1B]) and three genes encoding D2-like receptors (D2/D3/D4). We review here our recent work on the cloning and characterization of some of the members of the dopamine receptor gene family (D1, D2, D4, D5), their relationship to neuropsychiatric disorders and their potential role in antipsychotic drug action.  相似文献   
60.
X-linked lymphoproliferative disease (XLP) is a rare immunodeficiency caused by mutations in the signaling lymphocyte activating molecule-associated protein/SH2D1A gene and characterized by a dysregulated immune response to Epstein-Barr virus and other pathogens. The clinical presentation is heterogeneous and includes fulminant infectious mononucleosis, lymphoma, hypogammaglobulinemia and aplastic anemia. XLP is associated with a high morbidity and overall outcome is poor. At present, allogeneic stem cell transplantation (alloSCT) is the only curative treatment. XLP patients may be recognized in various stages of disease and even when symptoms are not yet evident. We here present two related XLP patients in different stages of disease that were both treated successfully with alloSCT using a matched unrelated donor. In addition, we have reviewed all reported cases of alloSCTs in XLP patients. Based on these results and in order to improve the final outcome, we conclude that alloSCT should be recommended in both symptomatic and asymptomatic XLP patients.  相似文献   
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