Citations

Background and Purpose— Little is known about the relationship between perihematomal edema in spontaneous intracerebral hemorrhage (ICH) and outcome. The purpose of this study was to determine whether absolute or relative edema volume (edema volume divided by hematoma volume) predicts mortality or functional outcome in patients with hyperacute spontaneous ICH. We hypothesized that increasing baseline relative edema volume is associated with greater probability of poor functional outcome. Methods— This was a secondary analysis of a prospective, population-based study of hematoma growth in 142 patients with spontaneous ICH. Patients were imaged within 3 hours of onset, then 1 and 20 hours later. Our primary analysis excluded patients with anticoagulant use (n=7), underlying aneurysm/vascular malformation (n=9), trauma (n=1), incomplete data (n=20), infratentorial ICH (n=17), intraventricular extension (n=38), and no consent (n=2). We analyzed whether associations existed between baseline edema volumes or other clinical/radiological variables and either 12-week modified Rankin Scale score >2 or 30-day mortality. Secondary analyses used 20-hour CT scan data, all patients with supratentorial ICH, and 12-week Barthel Index score <85. Results— By multivariable logistic regression analysis, baseline relative edema was the strongest independent predictor of functional outcome and was associated with lesser odds of poor 3-month functional outcome (odds ratio, 0.09 per 1.0-unit [100%] increase; 95% CI, 0.01 to 0.64; P =0.016) and 12-week Barthel Index score <85 (odds ratio, 0.12; 95% CI, 0.02 to 0.91; P =0.039) but did not predict mortality. Secondary analyses confirmed this result. Absolute edema volume predicted neither mortality nor functional outcome. Conclusions— Relative edema is strongly predictive of functional outcome in patients with hyperacute supratentorial spontaneous ICH without intraventricular extension.

Background— Although 192 Ir intracoronary brachytherapy has been demonstrated to dramatically reduce the recurrence of in-stent restenosis, up to 24% of these patients will still require repeat target-vessel revascularization. The short- and long-term outcomes of repeat percutaneous intervention in this population have not been characterized. Methods and Results— Analysis was performed of all patients enrolled in the GAMMA-I and GAMMA-II brachytherapy trials who underwent repeat percutaneous target lesion revascularization (TLR) because of restenosis. Subjects were divided into 2 cohorts: those who had received 192 Ir brachytherapy and those randomized to placebo. Forty-five (17.6%) of a total of 256 patients whose index treatment was intracoronary radiation therapy and 36 (29.8%) of 121 patients whose index treatment was placebo required repeat percutaneous TLR. The mean time to this first TLR was 295±206 days in the irradiated group and 202±167 days in the placebo group ( P =0.03). Acute procedural success occurred in 100% of irradiated patients and 94% of placebo controls ( P =0.19). After the first TLR, a subsequent TLR was required in 15 (33.3%) of 45 brachytherapy patients versus 17 (47.2%) of 36 placebo failure patients ( P =0.26). There was no significant difference in time to second TLR between the 2 groups. Other long-term major adverse event rates in both groups were comparable to those of other contemporary angioplasty/stenting series. Conclusions— In those patients who “fail” 192 Ir intracoronary brachytherapy for in-stent restenosis, treatment with 192 Ir delays the time to first TLR. Additionally, repeat percutaneous intervention in these patients is safe and efficacious in the short term, with acceptable long-term results.

AbstractNeurotrophins, such as nerve growth factor (NGF) and neurotrophin-3 (NT-3), are essential for development, function, and survival of peripheral sympathetic and sensory neurons. Most eosinophilic leukocytes in the human body are localized in mucosal tissues; however, the roles of eosinophils in human diseases are not fully understood. We found that human eosinophils constitutively express messenger RNA for NGF and NT-3, synthesize and store these proteins intracellularly, and continuously replenish them. Incubation of eosinophils with a transcription inhibitor, actinomycin D, for 8 hours completely depletes intracellular NGF and NT-3. New synthesis of NGF is enhanced by Fc-receptor–mediated stimuli, such as immunoglobulin (Ig)A and IgG immune complexes; in contrast, production of NT-3 is not affected by these stimuli. Notably, supernatants of eosinophils stimulated with IgA immune complex and interleukin 5 promote neurite extension of the PC-12 pheochromocytoma cell line; this effect is abolished by pretreatment of the supernatants with anti-NGF–neutralizing antibody. By enzyme-linked immunosorbent assay, substantial amounts of NGF protein are also detected in the supernatants of stimulated eosinophils. Furthermore, in patients with seasonal allergic rhinitis, the concentrations of NGF in nasal secretions correlate with the magnitudes of eosinophilic inflammation in the airway, suggesting a potential clinical implication of eosinophil NGF. Our observations propose a new pathologic mechanism by which eosinophils may contribute to enhanced neurologic responses in patients with allergic diseases and other eosinophilic disorders. Alternatively, eosinophils may play important roles in maintenance and restoration of homeostatic functions of mucosal tissues through the pleitropic activities of NGF.

ABSTRACT Gene therapy in eukaryotes has met many obstacles. Research into the design of suitable nonviral vectors has been slow. To our knowledge, no nonviral vector has been proposed that allows for the possibility of highly efficient, site‐selective integration into the genome of mammalian cells. On the basis of prior studies investigating the components necessary for transposon, retrovirus‐like retrotransposon, and retroviral integration, we propose a nonviral system that would potentially allow for site‐selective, efficient integration into the mammalian genome. Transposons have been developed that can transform a variety of cell lines. For example, the Sleeping Beauty transposon (SB) can transform a wide range of vertebrate cells from fish to human, and it mediates stable integration and long‐term transgene expression in mice. However, the efficiency of transposition varies significantly among cell lines, suggesting the possible involvement of host factors in SB transposition. Here, we propose the use of a chimeric transposase (i.e., transposase‐host DNA binding domain) to bypass the potential requirement of a host DNA‐directing factor (or factors) for efficient, site‐selective integration. We also discuss another potential method of docking the transposonbased vector adjacent to the host DNA, utilizing repetitive sequences for homologous recombination to promote efficient site‐selective integration, as well as other site‐selective nonviral approaches.—Kaminski, J. M., Huber, M. R., Summers, J. B., Ward, M. B. Design of a nonviral vector for site‐selective, efficient integration into the human genome. FASEB J . 16, 1242–1247 (2002)

Background— The outcome of mitral valve prolapse (MVP) is controversial, with marked discrepancies in reported complication rates. Methods and Results— We conducted a community study of all Olmsted County, Minn, residents first diagnosed with asymptomatic MVP between 1989 and 1998 (N=833). Diagnosis, motivated by auscultatory findings (n=557) or incidental (n=276), was always confirmed by echocardiography with the use of current criteria. End points analyzed during 4581 person-years of follow-up were mortality (n=96, 19±2% at 10 years), cardiovascular morbidity (n=171), and MVP-related events (n=109, 20±2% at 10 years). The most frequent primary risk factors for cardiovascular mortality were mitral regurgitation from moderate to severe ( P =0.002, n=131) and, less frequently, ejection fraction <50% ( P =0.003, n=31). Secondary risk factors independently predictive of cardiovascular morbidity were slight mitral regurgitation, left atrium ≥40 mm, flail leaflet, atrial fibrillation, and age ≥50 years (all P <0.01). Patients with only 0 or 1 secondary risk factor (n=430) had excellent outcome, with 10-year mortality of 5±2% ( P =0.17 versus expected), cardiovascular morbidity of 0.5%/y, and MVP-related events of 0.2%/y. Patients with ≥2 secondary risk factors (n=250) had mortality similar to expected ( P =0.20) but high cardiovascular morbidity (6.2%/y, P <0.01) and notable MVP-related events (1.7%/y, P <0.01). Patients with primary risk factors (n=153) showed excess 10-year mortality (45±9%, P =0.01 versus expected), high morbidity (18.5%/y, P <0.01), and high MVP-related events (15%/y, P <0.01). Conclusions— Natural history of asymptomatic MVP in the community is widely heterogeneous and may be severe. Clinical and echocardiographic characteristics allow separation of the majority of patients with excellent prognosis from subsets of patients displaying, during follow-up, high morbidity or even excess mortality as direct a consequence of MVP.

Background— Atherosclerotic renovascular disease may augment deterioration of renal function and ischemic nephropathy compared with other causes of renal artery stenosis (RAS), but the underlying mechanisms remain unclear. This study was designed to test the hypothesis that concurrent early atherosclerosis and hypoperfusion might have greater early deleterious effects on the function and structure of the stenotic kidney. Methods and Results— Regional renal hemodynamics and function at baseline and during vasoactive challenge (acetylcholine or sodium nitroprusside) were quantified in vivo in pigs by electron-beam computed tomography after a 12-week normal (n=7) or hypercholesterolemic (HC, n=7) diet, RAS (n=6), or concurrent HC and a similar degree of RAS (HC+RAS, n=7). Flash-frozen renal tissue was studied ex vivo. Basal cortical perfusion and single-kidney glomerular filtration rate (GFR) were decreased similarly in the stenotic RAS and HC+RAS kidneys, but tubular fluid reabsorption was markedly impaired only in HC+RAS. Perfusion responses to challenge were similarly blunted in the experimental groups. Stimulated GFR increased in normal, HC, and RAS (38.3±3.6%, 36.4±7.6%, and 60.4±9.3%, respectively, P <0.05), but not in HC+RAS (6.5±15.1%). These functional abnormalities in HC+RAS were accompanied by augmented perivascular, tubulointerstitial, and glomerular fibrosclerosis, inflammation, systemic and tissue oxidative stress, and tubular expression of nuclear factor-κB and inducible nitric oxide synthase. Conclusions— Early chronic HC+RAS imposes distinct detrimental effects on renal function and structure in vivo and in vitro, evident primarily in the tubular and glomerular compartments. Increased oxidative stress may be involved in the proinflammatory and progrowth changes observed in the stenotic HC+RAS kidney, which might potentially facilitate the clinically observed progression to end-stage renal disease.

AbstractWhat is the future of thyroid surgery in the new millennium? How can surgeons keep abreast of advances in thyroid endocrinology, genetics, surgical therapy, and other aspects of thyroid disease management? How should surgeons be trained to become highly competent in thyroid disease and to perform safe, effective thyroid operative procedures? Nine internationally recognized endocrine surgeons were asked to express their views on these and related subjects. They noted that advances in molecular biology, pathology, and genetics of thyroid disease should allow more tailored surgical approaches during the twenty‐first century. Current training of general surgical residents in thyroid and other types of endocrine surgery is highly variable, which may contribute to increased complication rates and number of second operations. The leadership for addressing these deficiencies and promoting a more organized approach to thyroid disease management should come from national endocrine surgery associations and their leaders. It is incumbent upon endocrine surgeons to maintain their central role in the management of many aspects of thyroid disease. Organizing teams of specialists into thyroid centers (centers of excellence) can (1) increase efficiency; (2) increase quality of care; (3) decrease costs; (4) encourage a more individualized approach to surgery; (5) lower complication rates; and (6) foster innovation in technology and disease management. Two years of additional fellowship training in thyroid and endocrine surgery is now being advocated by increasing numbers of national endocrine surgical associations as the best way to prepare surgeons for society's needs for highly skilled, competent thyroid surgeons of the future.

Background and Purpose — The aim of the study was to evaluate the relationship between daily aspirin use and urinary excretion of a stable thromboxane metabolite, 11-dehydrothromboxane B 2 (11-DTB2), in African American stroke patients. Methods — Subjects were a subgroup of those screened for the African American Antiplatelet Stroke Prevention Study. Subjects were within 4 months of noncardioembolic ischemic stroke and were not being treated with anticoagulants. Antithrombotic therapy at the time of urine collection varied according to the practice patterns of various attending physicians who treated the patients during their acute strokes. 11-DTB2 was measured by enzyme immunoassay in random urine samples 1 to 4 months after the stroke. Results — Eighty-seven of 92 patients enrolled were able to give a urine sample at the time of enrollment. There were 51 men and 36 women aged 36 to 87 (mean 62) years. On the basis of antithrombotic treatment before the sample collection, we divided patients into 4 groups: (1) 16 patients treated with no aspirin (no antithrombotic drugs [n=4] or ticlopidine [n=12]), (2) 21 patients treated with 81 to 325 mg aspirin per day (81 mg/d [n=2], 325 mg/d [n=19]), (3) 20 patients treated with 650 mg aspirin per day, and (4) 30 patients treated with 975 to 1300 mg aspirin per day (975 mg/d [n=2] and 1300 mg/d [n=28]). In patients taking daily aspirin at any dose, the median urinary 11-DTB2 was 783 pg/mg creatinine compared with 1386 pg/mg creatinine in patients not taking daily aspirin ( P =0.01 by Wilcoxon rank sum test). In multivariate regression analysis, aspirin use remained significantly associated with lower urinary 11-DTB2 ( P =0.008). There was no dose-response effect between the 3 aspirin dose groups and urinary 11-DTB2 ( P =0.70). Conclusions — In African American stroke patients, aspirin use is associated with significantly lower urinary 11-DTB2 independent of other vascular factors, and there does not appear to be a dose-response effect for aspirin doses of 325 to 1300 mg daily. The clinical significance of these finding remains to be determined.

Directed protein evolution, which employs a combination of random mutagenesis, phage display, and in vitro selection, was used to identify second-site suppressors of the fibronectin (Fn) cell binding domain mutation Asp1495Ala (RGA). The mutations in the Fn 9th (3fn9) and 10th (3fn10) type III repeats obtained after selection on purified integrins αIIbβ3(D119Y) and α5β1 are reported. The 3fn9–10(D1495A) phage with substitution mutations at Asp1418, which is located within the linker region between 3fn9 and 3fn10, enhanced binding to the integrins αIIbβ3 and α5β1, but not αvβ3. The substitution mutations identified at residue Asp1418 were introduced into the native recombinant 3fn9–10 sequence and found to augment binding to αIIbβ3, demonstrating that the observed gain-of-function phenotype was independent of the multivalent character of the phage. These results support the following conclusions. First, regions of Fn in addition to the RGD loop are in close proximity to αIIbβ3 and α5β1 and are capable of participating in the binding to these integrins. Secondly, the conformational relationship between the 3fn9 and 3fn10 modules may be an important factor in the binding of Fn to these two integrins. Thirdly, other altered properties of Fn-integrin interactions, such as integrin specificity, may also be selected. This is the first description of Fn mutations that augment binding to integrins. The ability to select for particular phenotypes in vitro and the subsequent characterization of these mutations should further our understanding of the molecular details involved in the association of integrins and their ligands. Additionally, these higher-affinity 3fn9–10 ligands provide a starting point for further in vitro evolution and engineering of integrin-specific modules.

Background — Despite the common occurrence of aortic stenosis, the cellular causes of the disorder are unknown, in part because of the absence of experimental models. We hypothesized that atherosclerosis and early bone matrix expression in the aortic valve occurs secondary to experimental hypercholesterolemia and that treatment with atorvastatin modifies this transformation. Methods and Results — To test this hypothesis, we developed an experimental hypercholesterolemic rabbit model. New Zealand White rabbits (n=48) were studied: group 1 (n=16), normal diet; group 2 (n=16), 1% (wt/wt) cholesterol diet; and group 3 (n=16), 1% (wt/wt) cholesterol diet plus atorvastatin (3 mg/kg per day). The aortic valves were examined with hematoxylin and eosin stain, Masson trichrome, macrophage (RAM 11), proliferation cell nuclear antigen (PCNA), and osteopontin immunostains. Cholesterol and highly sensitive C-reactive protein (hsCRP) serum levels were obtained by standard assays. Computerized morphometry and digital image analysis were performed for quantifying PCNA (% area). Electron microscopy and immunogold labeling were performed for osteopontin. Semiquantitative RT-PCR was performed for the osteoblast bone markers [alkaline phosphatase, osteopontin, and osteoblast lineage-specific transcription factor ( Cbfa-1 )]. There was an increase in cholesterol, hsCRP, PCNA, RAM 11, and osteopontin and osteoblast gene markers (alkaline phosphatase, osteopontin, and Cbfa-1 ) in the cholesterol-fed rabbits compared with control rabbits. All markers except hsCRP were reduced by atorvastatin. Conclusions — These findings of increased macrophages, PCNA levels, and bone matrix proteins in the aortic valve during experimental hypercholesterolemia provide evidence of a proliferative atherosclerosis–like process in the aortic valve associated with the transformation to an osteoblast-like phenotype that is inhibited by atorvastatin.