Correction to: Inhalation of specific anti-Pseudomonas aeruginosa IgY antibodies transiently decreases P. aeruginosa colonization of the airway in mechanically ventilated piglets.

Following publication of the original article [1], the authors flagged that an incorrect piece of data is given in the Materials and Methods section of the article.

Inhalation of specific anti-Pseudomonas aeruginosa IgY antibodies transiently decreases P. aeruginosa colonization of the airway in mechanically ventilated piglets.

BACKGROUND: P. aeruginosa is a pathogen frequently resistant to antibiotics and a common cause of ventilator-associated pneumonia (VAP). Non-antibiotic strategies to prevent or treat VAP are therefore of major interest. Specific polyclonal avian IgY antibodies have previously been shown to be effective against pneumonia caused by P. aeruginosa in rodents and against P. aeruginosa airway colonization in patients. OBJECTIVES: To study the effect of specific polyclonal anti-P. aeruginosa IgY antibodies (Pa-IgY) on colonization of the airways in a porcine model. METHOD: The pigs were anesthetized, mechanically ventilated, and subject to invasive hemodynamic monitoring and allocated to either receive 109 CFU nebulized P. aeruginosa (control, n = 6) or 109 CFU nebulized P. aeruginosa + 200 mg Pa-IgY antibodies (intervention, n = 6). Physiological measurement, blood samples, and tracheal cultures were then secured regularly for 27 h, after which the pigs were sacrificed and lung biopsies were cultured. RESULTS: After nebulization, tracheal growth of P. aeruginosa increased in both groups during the experiment, but with lower growth in the Pa-IgY-treated group during the experiment (p = 0.02). Tracheal growth was 4.6 × 103 (9.1 × 102-3.1 × 104) vs. 4.8 × 104 (7.5 × 103-1.4 × 105) CFU/mL in the intervention group vs. the control group at 1 h and 5.0 × 100 (0.0 × 100-3.8 × 102) vs. 3.3 × 104 (8.0 × 103-1.4 × 105) CFU/mL at 12 h in the same groups. During this time, growth in the intervention vs. control group was one to two orders of ten lower. After 12 h, the treatment effect disappeared and bacterial growth increased in both groups. The intervention group had lower body temperature and cardiac index and higher static compliance compared to the control group. CONCLUSION: In this porcine model, Pa-IgY antibodies lessen bacterial colonization of the airways.

Demonstration of polarization pulling using a fiber-optic parametric amplifier.

We report the observation of all-optical polarization pulling of an initially polarization-scrambled signal using parametric amplification in a highly nonlinear optical fiber. Broadband polarization pulling has been achieved both for the signal and idler waves with up to 25 dB gain using the strong polarization sensitivity of parametric amplifiers. We further derive the probability distribution function for the final polarization state, assuming a randomly polarized initial state, and we show that it agrees well with the experiments.

Spectral broadening of a partially coherent CW laser beam in single-mode optical fibers.

The nonlinear propagation of a partially coherent continuous-wave laser beam in single-mode optical fibers is investigated both theoretically and experimentally, with a special attention to the zero-dispersion wavelength region where modulation instability is expected. Broadband asymmetric spectral broadening is reported experimentally and found in fairly good agreement with a numerical Schrödinger simulation including a phase-diffusion model for the partially coherent beam. This model shows in addition that the underlying spectral broadening mechanism relies not only on modulation instability but also on the generation of high-order soliton-like pulses and dispersive waves. The coherence degradation which results from these ultrafast phenomena is confirmed by autocorrelation measurement.

Image Upconversion from the Visible to the UV Domain: Application to Dynamic UV Microstereolithography.

We present what to our knowledge is a new application of optical frequency upconversion of images in quadratic materials to dynamic UV microstereolithography. A 150 x 150 point visible image transmitted by a liquid-crystal display was upconverted in a lithium triborate crystal, and the UV image was successfully used to polymerize a commercial stereolithographic resin.

Gain in phase sensitive parametric image amplification

We report an experiment of type 2 parametric image amplification in a phase sensitive configuration. In the spatial frequency domain, the parametric gain corresponds to amplification or deamplification, depending on the relative phase of the input image with respect to the pump wave and on the spatial frequencies of the input image.

The coming millennium: enduring issues confronting Catholic health care.

Professor Singer and Ms. Johnson Lantz provide a cogent overview of Catholic health care in the United States and address the key issues affecting Catholic health care in the coming years. In particular, (1) clarity in canonical and ethical interpretation; (2) industry consolidation; and (3) "next generation" sponsorship and the impact of these issues are discussed in detail. The authors conclude that successful Catholic health care organizations must maintain strong mission and business fundamentals in an increasingly competitive reimbursement and regulatory environment.

Two-dimensional time-resolved direct imaging through thick biological tissues: a new step toward noninvasive medical imaging.

We report an original two-dimensional time-resolved direct imaging method for transillumination optical tomography that combines the time-gating and forward phase-conjugation properties of type II degenerate parametric amplification. An object with subcentimeter resolution embedded in 4-cm-thick chicken breast tissue was imaged with a signal-to-noise ratio of 2.

Raman-assisted parametric frequency conversion in a normally dispersive single-mode fiber.

We demonstrate efficient frequency conversion with large frequency shifts of an anti-Stokes signal into a parametrically seeded Stokes idler, which is generated by a highly mismatched three-wave mixing interaction and subsequent Raman amplification in a normally dispersive single-mode fiber. The use of non-phase-matched waves in Raman-assisted three-wave mixing interactions overcomes the strict spectral limitations imposed by phase-matching conditions in parametric frequency-conversion processes.

Image restoration through aberrant media by optical phase conjugation in a type II three-wave mixing interaction.

Restoration of an image through an aberrant plate has been achieved by use of optical phase conjugation in a type II parametric interaction in which the amplified signal and idler waves are reflected back through the aberrant medium. The resolution of the restored phase-conjugate images is equal to 0.18 mm, and the amplification gain is ~4dB.

Imaging through scattering media by parametric amplification of images: study of the resolution and the signal-to-noise ratio.

An imaging scheme through scattering media in which parametric image amplification is used is presented. An image of a resolution chart through a solution of latex microspheres with an attenuation of 22 mean free paths is obtained with a resolution of 20 mum. The evolution of the signal-to-noise ratio with respect to the medium attenuation is studied and compared with a rough modeling of the imaging process.

Barium enema: detection of colonic lesions in a community population.

OBJECTIVE: The purposes of this study were to assess the prevalence of colonic lesions detected at barium enema in a community practice, to compare the findings at barium enema between patients who are asymptomatic and have no known risk factors for colorectal cancer (screening group) and patients who have symptoms of colonic disease or have known risk factors, and to determine if a questionnaire about symptoms and risk factors is an appropriate screening tool. SUBJECTS AND METHODS: A self-administered questionnaire about colorectal symptoms and risk factors was given to 1779 patients scheduled for barium enema examination. On the basis of their responses, patients were divided into three groups: screening group (asymptomatic, without risk factors), symptomatic, and asymptomatic with risk factors. Each patient underwent a fluoroscopic barium enema. We then compared the results (number, histologic type, size of lesion(s), location in the colon, and Patient's age) and risk factors among the three groups. RESULTS: At least one lesion within the colorectum was found in 166 (9%) of 1779 patients at combined proctosigmoidoscopy and barium enema. The prevalence of lesions in the 111 patients with at least one lesion above the rectum at barium enema was 4% (32 of 738) for the screening group, 8% (38 of 476) for asymptomatic patients with risk factors, and 7% (41 of 565) for symptomatic patients (p = .015 when comparing the prevalence in the screening group with the prevalences in the other two groups). Twenty-nine percent of all colonic lesions were found in the screening group. Among the asymptomatic patients, risk factors that included a history of colorectal polyps and advanced age were associated with a significantly higher prevalence of colonic polyps found at barium enema. In the symptomatic group, if patients with histories of polyps were excluded, we were unable to identify other risk factors that led to a significantly higher prevalence of polyps. CONCLUSION: Asymptomatic patients without known risk factors have a significantly lower prevalence of colonic polyps than either symptomatic patients or patients with risk factors alone. Despite this lower prevalence, 29% of all lesions in our series were in the screening group. Assessment of risk factors through a patient questionnaire was not helpful in identifying a group of patients with a higher prevalence of lesions--except for a history of polyps. Management decisions based on a patient questionnaire should be approached with caution. When low-risk patients are denied screening examinations, a significant number of lesions will be missed.

Intraoperative color Doppler sonography during renal artery revascularization.

Intraoperative color Doppler sonography is emerging as a useful procedure for evaluating renal arteries during transaortic renal endarterectomy or bypass grafting. Technical difficulties encountered during surgical renal revascularization, such as intimal defects or flaps, partial or complete thrombosis, and anastomotic stenosis of the renal artery, can be difficult to defect and evaluate. Intraoperative color Doppler sonography allows evaluation at a time when the problem is often correctable. We have been performing intraoperative sonographic studies of the renal artery for several years and have studied 151 vessels. In this pictorial essay, we present some of our observations on these cases.

Fibrinolysis in cornea and conjunctiva: evidence of two types of activators.

The nature of corneal and conjunctival plasminogen activators (PAs) from human and rabbit eyes was examined in tissue culture. The fibrinolytic activity of culture fluid from human corneas was low, roughly one-eighth of that of rabbits. The main activity was found to be of the urokinase (UK) type, as demonstrated by crossed immunoelectrophoresis against alpha 2-antiplasmin after incubation with mixed plasma. The fibrinolytic activity of culture fluid from human conjunctival tissue was higher and a mixed secretion of tissue type (tPA) and UK activator was demonstrated. These activators were separated by affinity chromatography against Sepharose-immobilized antibodies against tPA. Fibrinolytic activity in tears was quenched by antibodies against tPA but not by the use of anti-UK antibodies. Thus, in man, tear fibrinolytic activity may depend primarily on a release of PAs from conjunctival tissue.