Acute hypoxemia leads to activation of the sympathetic nervous system (SNS), yet adrenergic vasoconstriction does not occur and venous plasma norepinephrine (NE) fails to rise as expected. To examine whether this dissociation between SNS tone and plasma NE is due to altered metabolism of NE, we measured arterial NE kinetics ([3H]NE infusion technique) and sympathetic nervous outflow to muscle (peroneal microneurography) during 25-30 min of hypoxemia (spontaneous breathing, mean O2 saturation 74%) in six healthy young men. During hypoxemia, muscle sympathetic nervous activity (MSNA) rose significantly from 12.2 +/- 3.3 to 18.6 +/- 3.5 bursts/min, and the total amplitude increased from 123 +/- 36 to 255 +/- 50 mm/min. NE spillover, an index of NE release at the sympathetic nerve terminals, rose from 1.66 +/- 0.30 to 2.33 +/- 0.40 nmol.min-1.m-2 (P = 0.014). However, NE clearance increased also from 0.99 +/- 0.05 to 1.19 +/- 0.11 l.min-1.m-2 (P = 0.014), and arterial NE rose from 281 +/- 50 to 339 +/- 64 pg/ml (P = 0.023). Hypoxemia resulted in a significant rise in forearm blood flow and a decrease in forearm vascular resistance. The fact that skin blood flow and vascular resistance did not change implies that forearm vasodilation was localized to skeletal muscle. Our results suggest that during acute hypoxemia in humans the SNS is activated but the rise in plasma NE is attenuated because NE clearance is increased.

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Background Age-related macular degeneration remains the leading cause of irreversible blindness in the United States and the developed world. Intravitreal injections of anti–vascular endothelial growth factor (VEGF) medications have become standard of care for the treatment of the wet form of the disease. Recent reports have demonstrated an association with various immune factors. We aimed to investigate the effect of immunosuppressive therapy in the clinical course of the wet form of the disease. We compared anti-VEGF therapy plus one of three systemic immunosuppressive therapies versus anti-VEGF therapy alone for recurrent choroidal neovascularization associated with age-related macular degeneration. Methods This was a pilot, Phase I/II, prospective, randomized, unmasked, single-center trial. Patients with subretinal exudation secondary to recurrent choroidal neovascularization associated with age-related macular degeneration were included in the study. Patients were randomized to 1 of 3 systemic arms immunosuppressive agents (daclizumab, rapamycin, or infliximab) for 6 months plus intraocular anti-VEGF therapy if indicated, compared with a group who received only anti-VEGF therapy if indicated. Results The number of anti-VEGF injections per group, visual acuity, retinal thickness, and safety measures were assessed in all groups. Thirteen patients were randomized; comparing anti-VEGF injections before and during the study, a decrease in the number of injections from 0.73 injections per month to 0.42 for daclizumab and from 0.67 to 0.34 for sirolimus was seen, while no apparent decrease was seen for either infliximab or observation. Visual acuities were maintained in all groups. Conclusion These preliminary data suggest that some immunosuppressive agents given systemically can alter the clinical course of the wet form of the disease and support the notion that more definitive clinical trials of immune mediation of age-related macular degeneration are indicated.

The diagnosis of presumed ocular tuberculosis remains a clinical challenge with currently available diagnostic modalities. Although newer interferon-γ release assays can distinguish exposure to M. tuberculosis from the Bacille-Calmette-Guérin vaccine strain, they currently lack the specificity to distinguish between latent tuberculosis infection and active tuberculosis. Continued improvement in the currently available molecular diagnostic techniques including quantitative PCR may be valuable in our ability to establish an earlier etiologic diagnosis and institute appropriate antimycobacterial therapy.

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Purpose-This study was designed to provide preliminary data regarding the safety and efficacy of high-dose humanized anti-IL-2 receptor (daclizumab) therapy for the treatment of active intermediate, posterior or panuveitis.Methods-Five patients were recruited into this non-randomized, prospective pilot study of highdose intravenous induction daclizumab therapy given at doses of 8 mg/kg at day 0 and 4 mg/kg at day 14. Patients who did not meet a safety endpoint at the 3-week follow-up evaluation were given the option of continuing therapy with subcutaneous daclizumab at 2 mg/kg every 4 weeks for 52 weeks. The primary outcome assessed was a 2-step decrease in vitreous haze at day 21. Secondary outcomes evaluated included best-corrected visual acuity, retinal thickness as measured by optical coherence tomography, retinal vascular leakage assessed by fluorescein angiography, anterior chamber and vitreous cellular inflammation.Results-4 male patients and 1 female patient were enrolled. Diagnoses included birdshot retinochoroidopathy (2 patients), Vogt-Koyanagi-Harada's disease, bilateral idiopathic panuveitis and bilateral idiopathic intermediate uveitis. By the 4 th week, four of five patients demonstrated a 2-step decrease in vitreous haze. The other participant did not meet this criterion until week 20, but all 5 patients maintained stability in vitreous haze grade throughout their follow-up periods. At enrollment, mean visual acuity (10 eyes in five patients) was 69.2 ETDRS letters and following treatment was 78.2 letters (p < 0.12). Anterior chamber cell, vitreous cell, and vitreous haze also improved in the majority of eyes. Adverse events were generally mild except for one episode of leftlower lobe pneumonia requiring hospitalization and treatment.Conclusion-This is the first demonstration that high-dose daclizumab can reduce inflammation in active uveitis. Daclizumab was well-tolerated but there may be a potential increased risk of infection associated with immunosuppression. All five patients demonstrated a decrease in vitreous haze and measures of intraocular inflammation at final follow-up. The results of this small,

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Vitrectomy may be safely performed in ocular trauma with opaque cornea using a temporary keratoprosthesis or endoscopy with comparable outcomes. Endoscopy allows earlier diagnosis and treatment of occult pathology and requires less time and fewer procedures to implement than the temporary keratoprosthesis.