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Purpose To evaluate the spectrum of and determine the risk factors for the development of liver toxicity (hepatopathy) after therapy with vincristine, dactinomycin, and cyclophosphamide (VAC) for rhabdomyosarcoma in children and adolescents. Patients and Methods We prospectively captured all events of hepatopathy occurring on the ongoing Children's Oncology Group intermediate risk protocol, D9803, for children with rhabdomyosarcoma. Patients enrolled onto this trial were randomly assigned to receive either VAC alone or VAC alternating with vincristine, topotecan, and cyclophosphamide. In addition, we reviewed the toxicity database and requested additional information for all patients with elevated bilirubin or transaminase levels. Risk factors were analyzed. Results Of 339 patients enrolled through August 2002, 18 developed hepatopathy. All events were captured by mandated toxicity reporting and filing of MedWatch forms, with no additional cases found after the additional search of the database. Four children died after developing this toxicity. All cases occurred after cycles of VAC (n = 16) or vincristine and cyclophosphamide with concomitant abdominal radiotherapy (n = 2). The onset of hepatopathy was 5 to 16 days from the start of a treatment cycle. For the 89 patients under 36 months of age, the risk of hepatopathy was 15%, with two deaths. For the 239 children 3 years of age or older, the risk for hepatopathy was 4%, with two deaths. Conclusion The greatest risk factor for development of hepatopathy after VAC therapy was age. Dose modifications for younger children receiving VAC therapy are recommended.

Rupture of an intracranial aneurysm (subarachnoid hemorrhage) is a potentially devastating condition frequently complicated by delayed cerebral ischemia from sustained contraction of intracranial arteries (cerebral vasospasm). There is mounting evidence linking the formation of intracranial aneurysms and the pathogenesis of post-subarachnoid hemorrhage vasospasm to aberrant bioavailability and action of the vasodilator molecule nitric oxide generated by isoforms of nitric oxide synthase. In humans, the gene encoding the endothelial isoform of nitric oxide synthase (eNOS) is known to be polymorphic, with certain polymorphisms associated with increased cardiovascular disease susceptibility. In this prospective clinical study involving 141 participants, we used gene microarray technology to demonstrate that the eNOS gene intron-4 27-base pair variable number tandem repeat polymorphism (eNOS 27 VNTR) predicts susceptibility to intracranial aneurysm rupture, while the eNOS gene promoter T-786C single nucleotide polymorphism (eNOS T-786C SNP) predicts susceptibility to post-subarachnoid hemorrhage vasospasm. We believe that genetic information such as this, which can be obtained expeditiously at the time of diagnosis, may be used as a helpful adjunct to other clinical information aimed at predicting and favorably modifying the clinical course of persons with intracranial aneurysms.

Gene transfer involves the use of an engineered biologic vehicle known as a vector to introduce a gene encoding a protein of interest into a particular tissue. In diseases with known defects at a genetic level, gene transfer offers a potential means of restoring a normal molecular environment via vector-mediated entry (transduction) and expression of genes encoding potentially therapeutic proteins selectively in diseased tissues. The technology of gene transfer therefore underlies the concept of gene therapy and falls under the umbrella of the current genomics revolution. Particularly since 1995, numerous attempts have been made to introduce genes into intracranial blood vessels to demonstrate and characterize viable transduction. More recently, in attempting to translate cerebrovascular gene transfer technology closer to the clinical arena, successful transductions of normal human cerebral arteries ex vivo and diseased animal cerebral arteries in vivo have been reported using vasomodulatory vectors. Considering the emerging importance of gene-based strategies for the treatment of the spectrum of human disease, the goals of the present report are to overview the fundamentals of gene transfer and review experimental studies germane to the clinical translation of a technology that can facilitate genetic modification of cerebral blood vessels.

This experiment examined the effects of nitric oxide (NO) synthase inhibition on brain intracellular pH, regional cortical blood flow, and NADH fluorescence before and during 3 h of focal cerebral ischemia using in vivo fluorescence imaging. Thirty fasted rabbits under 1% halothane were divided into four treatment groups receiving N ω -nitro-L-arginine methyl ester (L-NAME) intravenously at 20 min prior to ischemia (0.1, I, and 10 mg/kg and 1 mg/kg + 5 mg/kg L-arginine) and two control groups (nonischemic and ischemic). In ischemic controls, brain pH i declined to 6.73 ± 0.03 at 30 min and remained acidotic through the remainder of the ischemic period. In the 0.1 mg/kg group, brain pH i fell after 30 min of ischemia to 6.76 ± 0.05 ( p < 0.05), but then improved progressively despite occlusion. In the 1 mg/kg group, brain pH i remained normal despite middle cerebral artery (MCA) occlusion. In the 10 mg/kg group and in the combined L-NAME + L-arginine group, pH i fell after 30 min of ischemia to 6.81 ± 0.03 ( p < 0.05) and remained acidotic. During occlusion, regional cortical blood flow dropped in a dose-dependent manner. After 3 h of ischemia, regional cortical blood flow was 33.9 ± 10.9 and 25.1 ± 8.9 ml/100 g/min at doses of 0.1 and 10.0 mg/kg, respectively. L-NAME treatment did not significantly alter the increased NADH fluorescence that accompanied occlusion. This study shows that L-NAME can prevent intracellular brain acidosis during focal cerebral ischemia independent from regional cortical blood flow changes. This experiment suggests that NO is involved in pH i regulation during focal cerebral ischemia.

Gene therapy is being investigated as a putative treatment option for cardiovascular diseases, including cerebral vasospasm. Because there is presently no information regarding gene transfer to human cerebral arteries, the principal objective of this study was to characterize adenovirus-mediated expression and function of recombinant endothelial nitric oxide synthase (eNOS) gene in human pial arteries. Pial arteries (outer diameter 500 to 1000 μm) were isolated from 30 patients undergoing temporal lobectomy for intractable seizures and were studied using histologic staining, histochemistry, electron microscopy, and isometric force recording. Gene transfer experiments were performed ex vivo using adenoviral vectors encoding genes for bovine eNOS (AdCMVeNOS) and Escherichia coli β-galactosidase (AdCMVLacZ). In transduced arteries, studied 24 hours after exposure to vectors, expression of recombinant β-galactosidase and eNOS was detected by histochemistry, localizing mainly to the adventitia (n = 4). Immunoelectron microscopy localized recombinant eNOS in adventitial fibroblasts. During contractions to U46619, bradykinin-induced relaxations were significantly augmented in AdCMVeNOS-transduced rings compared with control and AdCMVLacZ-transduced rings ( P < 0.01; n = 6). The NOS inhibitor L-nitroarginine methylester (L-NAME) caused significantly greater contraction in AdCMVeNOS-transduced rings ( P < 0.001; n = 4) and inhibited bradykinin-induced relaxations in control and transduced rings ( P < 0.001; n = 6). The current findings suggest that in AdCMVeNOS-transduced human pial arteries, expression of recombinant eNOS occurs mainly in adventitial fibroblasts where it augments relaxations to NO-dependent agonists such as bradykinin. Findings from the current study might be beneficial in future clinical applications of gene therapy for the treatment or prevention of cerebral vasospasm.

Background and Purpose—We sought to determine the incidence of recurrent stenosis after carotid endarterectomy.Methods—One thousand consecutive carotid endarterectomy patients were followed prospectively. The surgery was performed in a standard fashion. Cerebral protection was provided with intraoperative electroencephalographic monitoring and selective shunting. All arteriotomies were repaired with a patch graft. Each patient was seen 3 months after surgery and then yearly, with a duplex ultrasound obtained at each visit. Evidence for new ischemic events or recurrent stenosis of ≥70% was recorded.Results—The 30-day combined minor and major stroke and death rate was 1.9%. At 7.1-year follow-up, 0.1% of patients had recurrent stenosis ≥70%, the majority of which were asymptomatic.Conclusions—Carotid endarterectomy is a low-risk procedure for the treatment of carotid occlusive disease, with excellent long-term durability. Although less invasive, carotid angioplasty must demonstrate equal robustness in long-term follow-up before it is considered a routine alternative to surgery.

Background and Purpose— Anecdotal evidence exists for at least 2 subpopulations of intracranial saccular aneurysms, namely, those that may form rapidly and rupture when small versus those that enlarge slowly and may rupture particularly when ≥10 mm in diameter. We sought to determine whether the endothelial nitric oxide synthase (eNOS) T-786C single nucleotide polymorphism (SNP), implicated in cardiovascular disease susceptibility, could facilitate differentiation between small (≤5 mm) versus large (≥10 mm) ruptured aneurysms. Methods— In accordance with institutional guidelines, clinical data were recorded prospectively and genomic DNA was isolated from blood samples obtained from 52 aneurysmal subarachnoid hemorrhage (SAH) patients (cases) and 90 randomly selected controls. Samples were assayed for eNOS gene promoter T-786C SNP with the use of gene microarray technology. Statistical analyses included multiple logistic regression. Results— Although there was no difference in genotype distributions between cases and controls, all 13 patients with large aneurysms were ( T / C ) heterozygous for the polymorphism, while 9 of 22 patients (41%) with small aneurysms were ( T / T or C / C ) homozygous ( P =0.01). The mean (±SD) ruptured aneurysm diameter among all heterozygotes (8.5±5.2 mm) was significantly greater than that for C / C (6.0±2.3 mm) or T / T (4.7±1.8 mm) homozygotes ( P =0.04). With the use of multivariate analysis, heterozygosity remained significantly associated with aneurysm size ≥10 mm ( P =0.03). Conclusions— The eNOS T-786C SNP distinguishes genetically between small and large ruptured aneurysms. Although not predictive of SAH in the population at large, our data suggest that among persons with known intracranial aneurysms, eNOS T-786C genotype may be a factor influencing the size at which an aneurysm ruptures, a finding that should be taken into consideration along with other anatomic features of the aneurysm.

OBJECTIVEThe goal was to examine the current scope of otolaryngologists’ practices, their geographic distribution, and the roles otolaryngologists and other specialists play in caring for patients with otolaryngic and related conditions of the head and neck.STUDY DESIGNA large national survey and administrative claims databases were examined to develop practice profiles and compile a physician supply for otolaryngology. A focus group of otolaryngologists provided information to model future scenarios.RESULTSThe current and predicted workforce supply and demographics are at a satisfactory level and are decreasing as a proportion of the increasing population. Empiric data analysis supports the diverse nature of an otolaryngologist's practice and the unique role for otolaryngologists that is not shared by many other providers. Together with the focus group results, the study points to areas for which more background and training are warranted.CONCLUSIONSThis study represents a first step in a process to form coherent workforce recommendations for the field of otolaryngology.

Vasopeptidase inhibitors are potent new antihypertensive agents. The dual inhibition of ACE and neutral endopeptidase may result in synergistic humoral effects with unique hemodynamic actions. We investigated the hemodynamic and neurohumoral effects of vasopeptidase inhibition in conscious dogs made hypertensive by bilateral renal wrapping and subsequently instrumented for long-term assessment of left ventricular pressure and volume (n=8). Intravenous vasopeptidase inhibition (omapatrilat, 30 μmol/kg over 10 minutes) reduced peak left ventricular pressure (171±6 versus 130±6 mm Hg immediately after infusion, P <0.01) through arterial vasodilation (arterial elastance, 9.8±0.8 to 5.8±1.6 mm Hg/mL, P <0.01) and preload reduction (left ventricular end-diastolic volume, 51.1±6.8 to 46.0±6.9 mL, P <0.01). At 60 minutes, preload decreased further (40.5±5.9 mL, P <0.01 versus baseline). Vasopeptidase inhibition increased plasma levels of adrenomedullin (41.2±9.6 versus 72.3±15 pg/mL, P <0.01), whereas levels of the natriuretic peptides and cGMP were unchanged. Similar hemodynamic and humoral effects were observed with long-term therapy. Neither an equimolar dose of an ACE inhibitor (fosinopril) nor exogenous adrenomedullin had as potent of a hypotensive effect, and neither reduced preload. In summary, the potent short-term and long-term hypotensive effects of vasopeptidase inhibition were prominently mediated by preload reduction, an effect not reproduced by ACE inhibition nor adrenomedullin augmentation and not associated with enhanced natriuretic peptide levels. Combined arterial vasodilation and preload reduction may confer additional potency as well as unique cardioprotective effects. Synergistic effects on humoral and probably endothelial vasodilatory factors appear to be important in mediating the unique hemodynamic profile of vasopeptidase inhibition in this form of experimental hypertension.

ABSTRACT Anthrax is a zoonotic disease that is also well recognized as a potential agent of bioterrorism. Routine culture and biochemical testing methods are useful for the identification of Bacillus anthracis , but a definitive identification may take 24 to 48 h or longer and may require that specimens be referred to another laboratory. Virulent isolates of B. anthracis contain two plasmids (pX01 and pX02) with unique targets that allow the rapid and specific identification of B. anthracis by PCR. We developed a rapid-cycle real-time PCR detection assay for B. anthracis that utilizes the LightCycler instrument (LightCycler Bacillus anthracis kit; Roche Applied Science, Indianapolis, Ind.). PCR primers and probes were designed to identify gene sequences specific for both the protective antigen (plasmid pX01) and the encapsulation B protein (plasmid pX02). The assays (amplification and probe confirmation) can be completed in less than 1 h. The gene encoding the protective antigen ( pagA ) was detected in 29 of 29 virulent B. anthracis strains, and the gene encoding the capsular protein B ( capB ) was detected in 28 of 29 of the same strains. Three avirulent strains containing only pX01 or pX02, and therefore only pagA or pagB genes, could be detected and differentiated from virulent strains. The assays were specific for B. anthracis : the results were negative for 57 bacterial strains representing a broad range of organisms, including Bacillus species other than anthracis ( n = 31) and other non- Bacillus species ( n = 26). The analytical sensitivity demonstrated with target DNA cloned into control plasmids was 1 copy per μl of sample. The LightCycler Bacillus anthracis assay appears to be a suitable method for rapid identification of cultured isolates of B. anthracis . Additional clinical studies are required to determine the usefulness of this test for the rapid identification of B. anthracis directly from human specimens.