Objective To establish the safety and efficacy of endovascular repair of thoracoabdominal aortic aneurysms. Methods Between May 2004 and February 2006, patients with thoracoabdominal aneurysms ...considered high risk for conventional surgery were enrolled in a prospective trial to evaluate a novel endovascular grafting system. Devices were custom designed for each patient using high-resolution computed tomography. Patient data included mortality, morbidity, procedural details, and surrogate end points for endovascular repair. These were collected at hospital discharge and at 1, 6, and 12 months. Results Seventy-three patients underwent endovascular repair of thoracoabdominal aortic aneurysms for type I, II, or III (n = 28), or for type IV (n = 45) thoracoabdominal aneurysms. Mean aneurysm size was 7.1 cm (range 4.5–11.3 cm). General anesthesia was used in 47% of patients and regional anesthesia in 53%. There were no conversions to open surgery nor ruptures post-treatment. Technical success was achieved in 93% of patients (68/73). Thirty-day mortality was 5.5% (4/73). Major perioperative complications occurred in 11 (14%) patients and included paraplegia (2.7%, 2/73), new onset of dialysis (1.4%, 1/73), prolonged ventilator support (6.8%, 5/73), myocardial infarction (5.5%, 4/73), and minor hemorrhagic stroke (1.4%; 1/72). A majority of patients had no complications. Mean length of stay was 8.6 days. At follow-up, 6 deaths had occurred. There were no instances of stent migration nor aneurysmal growth. Conclusions Endovascular repair of aortic aneurysms involving the visceral segment in nonsurgical candidates is feasible. Known complications of repair are not eliminated, but morbidity and mortality appeared low relative to the high-risk population studied. Further refinement of device design, delivery technique, and patient selection is ongoing. Assessment of durability will require longer follow-up.
In contrast to internal iliac artery (IIA) occlusion, the use of branch stent-graft (BSG) has been developed as an efficient adjunct in preserving pelvic blood flow. However, the risk of ...post-procedural type 2 endoleak (EL) remains. We present the case of an 80-year-old man with a juxtarenal aneurysm extending to both common and IIA. The patient was treated with a fenestrated device and a left BSG after embolization of the right IIA branches. At 6 months, the persistence of a type 2 EL associated with aneurysm growth mandated EL embolization through the BSG with a good result. Technical issues are discussed.
Alterations in the fine structure of nuclei of ventromedial hypothalamic neurons in ovariectomized (OVX) rats after either a 2-hour exposure to estradiol (E2) or a discontinuous exposure (2 hours ...E2/7 hours off/2 hours E2), previously shown sufficient for female rat sexual behavior (Parsons et al., '82a), were examined with the electron microscope. Morphometric measurements of nucleolar, nuclear, and somal areas, and nuclear shape and perimeter were accomplished at the light microscope level. After 2 hours of E2, the appearance of the nucleoplasm was altered, with a decrease in the small, scattered clumps of heterochromatin. Nuclear shape appeared dramatically altered from nonspherical, invaginated profiles toward spherical, smooth profiles. Nucleolar, nuclear, and somal hypertrophy were evident. In addition, stacked rough endoplasmic reticulum was present more frequently in E2-treated than control OVX neurons. After the discontinuous (2 hours/7 hours/2 hours) E2 treatment, progressive loss of small clumps of heterochromatin along the nuclear envelope as well as in the nucleoplasm had occurred. Decrease in a large heterochromatin clump along the nuclear envelope was correlated with an increase in nucleolus-associated chromatin. As determined by a distribution analysis, these estrogen-induced nuclear changes co-occurred more frequently than predicted from mutual independence. These findings, the marked co-occurrence of E2-induced changes in 30% or more of the cells, and the differences between the 2-hour E2 and the 2-hour/7-hour/2-hour group are consistent with a cascade of cell nuclear changes in the first few hours after estrogen onset.
Recent evidence suggests that E2 may act in the ventromedial nucleus of the hypothalamus (VMN) and arcuate nucleus (ARC) through mechanisms partly unique to each area. To examine this hypothesis, we ...investigated early and discontinuous effects of E2 action on neurons within the ARC from an ultrastructural and morphometric perspective. In contrast to our findings of dramatic, rapid effects of E2 on the structure of VMN neurons, no changes in any of the ultrastructural parameters examined, including the nucleolus, nucleus, nucleoplasm, and the nuclear envelope-RER system, were observed in ARC neurons after either 2 hours of E2 or a discontinuous schedule of 2 h on/7 h off/2 h on of E2. No changes were noted in any of the quantitative parameters examined, including nucleolar, nuclear, and somal area, nuclear shape, and nuclear envelope length after either 2 hours of E2 or a discontinuous schedule of 2 h on/7 h off/2 h on of E2. These morphological results support the hypothesis of differential actions of E2 on various E2-concentrating nuclear groups in the brain.
In this study, changes in individual proteins in the ventromedial hypothalamus (VMN) and the preoptic area (POA) of the female rat brain were quantitatively assessed following either a short ...treatment (2 h) or a discontinuous schedule of estradiol. Ovariectomized (OVX) rats were implanted with estradiol capsules or sham-implanted for the appropriate paradigm and sacrificed by decapitation. Punches of brain tissue containing the VMN and POA were incubated with 35S-methionine and 35S-cysteine, and the labeled proteins separated by two-dimensional gel electrophoresis. Estradiol-induced changes were quantitatively assessed by computerized optical densitometry and subjected to a normalization procedure between pairs of estradiol-treated and OVX control gels. A number of proteins within the VMN and POA were found to be positively or negatively affected in labeling after either hormone administration paradigm. In both brain regions, the population of proteins affected in labeling after 2 h of estradiol treatment were markedly different from those affected after the discontinuous hormone paradigm. Comparison of the VMN and POA also indicated that the populations of proteins affected in labeling by either hormone treatment paradigm were different, with there being only 3 proteins (from a total of 39) affected in the same direction and 2 affected in the opposite direction by the hormone in both regions. These findings lend support to the hypothesis that administration of estradiol results in a molecular cascade of events within brain regions involved in the control of reproductive behavior.
In this study, the effects of 15 days of estradiol (E2) on tritiated-uridine incorporation were autoradiographically examined, on a cell-by-cell basis, in 4 E2-concentrating regions of the female rat ...brain. These areas included the ventromedial hypothalamus and medial amygdala nucleus, 2 regions involved in the behavioral components of reproduction, and the medial preoptic area and arcuate nucleus of the hypothalamus, 2 regions involved in the endocrine components of reproduction. Chronic E2 caused a 50% and 52% increase in tritiated-uridine incorporation in the arcuate nucleus and medial preoptic area, but was without effect in the ventromedial hypothalamus and medial amygdala nucleus. Somal area was also increased with E2 in the arcuate nucleus and medial preoptic area (16% and 43%, respectively) but not in the ventromedial hypothalamus and medial amygdala nucleus. The results indicate that the effects of estradiol on levels of newly synthesized RNA vary in a functionally and regionally specific manner within the brain.
In this study, quantitative assessment of the synergistic and independent effects of estradiol and progesterone on protein synthesis in the ventromedial hypothalamus (VMN) and the preoptic area (POA) ...was accomplished using in vitro 35S-methionine and 35S-cystein labeling, two-dimensional gel electrophoresis, and computerized densitometry. Ovariectomized (OVX) rats were divided into four groups. Group 1 was implanted with estradiol (E) capsules for 6 hr and injected with progesterone (P; 0.1 ml, 5 mg/ml propylene glycol) at 20 hr. Group 3 was sham-implanted for 6 hr and injected with 0.01 ml P at 20 hr. Group 4 was sham-planted for 6 hr and injected with vehicle alone at 20 hr. All animals were sacrificed at 24 hr. A number of proteins in both VMN and POA were found to be increased or decreased in labeling by E plus P, E alone, and P alone. Two important synergistic effects of the hormones were found. First, the effects of E on labeling of several proteins in both brain regions were countered by P, and conversely, the effects of P on labeling of several proteins in both brain regions were countered by E. Second, E priming increased the number of proteins affected in labeling by P in both brain regions. Comparison of the effects of E and P on proteins in the VMN and POA indicated that the populations of proteins affected in labeling were markedly different. These results begin to clarify the mechanism in which E and P affect neuronal functioning in two regions involved in the control of reproduction and lend support to the hypothesis that gonadal steroids accomplished their action on brain tissue via a mechanism that is partly unique to the brain region.
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