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981.
Cell-selective intracellular targeting is a key element of more specific and safe enzyme, toxin, and gene therapies. Endothelium poorly internalizes certain candidate carriers for vascular immunotargeting, such as antibodies to platelet endothelial cell adhesion molecule 1 (PECAM-1). Conjugation of poorly internalizable antibodies with streptavidin (SA) facilitates the intracellular uptake. Although both small and large (100-nm versus 1000-nm diameter) anti-PECAM/SA-beta galactosidase (SA-beta-gal) conjugates bound selectively to PECAM-expressing cells, only small conjugates showed intracellular accumulation of active beta-gal. To study whether size of the conjugates controls the uptake, a series of anti-PECAM/SA and anti-PECAM/bead conjugates ranging from 80 nm to 5 microm in diameter were produced. Human umbilical vein endothelial cells and PECAM-transfected mesothelioma cells internalized 80- to 350-nm anti-PECAM conjugates, but not conjugates larger than 500 nm. Further, size controls intracellular targeting of active therapeutic cargoes in vitro and in vivo. Small anti-PECAM/DNA conjugates transfected target cells in culture 5-fold more effectively than their large counterpart (350- versus 4200-nm diameter). To evaluate the practical significance of the size-controlled subcellular addressing, we coupled glucose oxidase (GOX) to anti-PECAM and antithrombomodulin. Both types of conjugates had equally high pulmonary uptake after intravenous injection in mice, yet only small (200- to 250-nm), not large (600- to 700-nm), GOX conjugates caused profound oxidative vascular injury in the lungs, presumably owing to intracellular generation of H(2)O(2). Thus, engineering of affinity carriers of specific size permits intracellular delivery of active cargoes to endothelium in vitro and in vivo, a paradigm useful for the targeting of drugs, genes, and toxins.  相似文献   
982.
OBJECTIVES: This study sought to determine whether combined assessment of autonomic tone plus cardiac electrical substrate identifies most patients at risk of serious events after myocardial infarction (MI) and to compare assessment at 2 to 4 weeks versus 10 to 14 weeks after MI. BACKGROUND: Methods to identify most patients at risk of serious events after MI are required. METHODS: Patients (n = 322) with an ejection fraction (EF) <0.50 in the initial week after MI were followed up for a median of 47 months. Serial assessment of autonomic tone, including heart rate turbulence (HRT), electrical substrate, including T-wave alternans (TWA), and EF was performed, interpreted blinded, and categorized using pre-specified cut-points where available. The primary outcome was cardiac death or resuscitated cardiac arrest. All-cause mortality and fatal or nonfatal cardiac arrest were secondary outcomes. RESULTS: Mean EF significantly increased over the initial 8 weeks after MI. Testing 2 to 4 weeks after MI did not reliably identify patients at risk, whereas testing at 10 to 14 weeks did. The 20% of patients with impaired HRT, abnormal exercise TWA, and an EF <0.50 beyond 8 weeks post-MI had a 5.2 (95% confidence interval [CI] 2.4 to 11.3, p < 0.001) higher adjusted risk of the primary outcome. This combination identified 52% of those at risk, with good positive (23%; 95% CI 17% to 26%) and negative (95%; 95% CI 93% to 97%) accuracy. Similar results were observed for the secondary outcomes. CONCLUSIONS: Impaired HRT, abnormal TWA, and an EF <0.50 beyond 8 weeks after MI reliably identify patients at risk of serious events. (Assessment of Noninvasive Methods to Identify Patients at Risk of Serious Arrhythmias After a Heart Attack; http://www.clinicaltrials.gov/ct/show/NCT00399503?order=1; NCT00399503).  相似文献   
983.
A randomized control trial was set up to examine factors that influence restenosis and determine the effects of corticosteroids on restenosis following successful PTCA. The rationale for the study agent chosen, design, recruitment, and feasibility, as well as initial patient demographic data and initial results are presented.  相似文献   
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987.
Abdominal Radiology - To evaluate the role of virtual monoenergetic&nbsp;imaging (VMI) in the detection of peritoneal metastatic disease in contrast-enhanced computed tomography (CT) of the...  相似文献   
988.
PurposeThe relationship between type 2 diabetes mellitus (T2DM) and increased microvascular and macrovascular disease and mortality is well established; however, data for the broad US T2DM population, especially by age, are limited. To help address this issue, we conducted a cohort study in a large national US commercially insured/Medicare Advantage population that incorporated a broad range of different age groups, including a large subset of younger individuals, during a 10-year study period.MethodsThis longitudinal study combined health plan claims and mortality data to identify incident T2DM patients and 1:1 directly matched non-DM controls. T2DM individuals (n = 13,883) were identified by a medical claim with a T2DM diagnosis or T2DM medication pharmacy claim in 2007; non-DM controls had no DM medical or pharmacy claims over the entire study period (January 1, 2006 to December 31, 2015). The outcomes assessed were incidence, prevalence, time to vascular disease and all-cause mortality, as well as age-stratified incidence and mortality based on Centers of Disease Control and Prevention–defined age strata.FindingsIndividuals with T2DM developed vascular disease at twice the rate as non-DM controls, 197 versus 98 per 1000 person-years, respectively. Vascular disease (composite) rates increased by age in T2DM/non-DM groups, 107.1/28.2 (18–44 years), 166.3/70.3 (45–64 years), and 391.0/199.7 (≥65 years) per 1000 person-years. The largest rate ratio was observed in younger individuals. All-cause mortality over follow-up was higher in T2DM individuals (27.5%) than in non-DM controls (19.6%). The largest increases in vascular disease prevalence and mortality among T2DM individuals were observed in the first year of follow-up.ImplicationsT2DM has a substantial effect on microvascular and macrovascular disease and all-cause mortality rates in all age groups. These outcomes appear to occur early after T2DM diagnosis, and have more pronounced, nearly fourfold, relative impact on younger individuals with T2DM compared to matched non-DM controls.  相似文献   
989.
Studies of the Neutropenia of Acute Malaria   总被引:4,自引:0,他引:4  
Dale  David C.; Wolff  Sheldon M. 《Blood》1973,41(2):197-206
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990.
The field of vascular endothelial growth factor (VEGF) has recently witnessed a surge of research into its role in diabetic kidney disease. Based on its credentials as a potent inducer of vasopermeability and angiogenesis, podocyte-derived VEGF is believed to participate in the glomerular capillary hyperpermeability of macromolecules that potentially underlies the pathogenesis of diabetic albuminuria. The evidence for VEGF’s role is relatively straightforward in animal models of diabetes, establishing that VEGF is upregulated in the diabetic kidney, that VEGF alone reproduces some aspects of diabetic glomerulopathy, and that antagonism of VEGF attenuates diabetic albuminuria and other associated features of the podocytopathy. However, the promise shown in the animal studies has not carried over as convincingly into the realm of human studies, as some investigators find a negative or no relationship between VEGF and diabetic nephropathy, whereas others find a positive correlation between the two. If VEGF does play a role in diabetic renal disease, its observed effects and known mechanisms seem to point squarely at the podocyte as a central target of the maladaptive VEGF overactivity.  相似文献   
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