Aerial image resolution measurement based on the slanted knife edge method.

Image resolution is one of the most important performance specifications of aerial display techniques. However, there is no standard method for evaluating the aerial image resolution. In this paper, we propose a method for measuring the modulation transfer function (MTF) of an aerial imaging system based on the slanted knife edge method. We hypothesize that aerial images have a different blur function from standard camera images. In order to explore this, we simulate blurred slanted knife edge images by convolving two types of blur functions. Furthermore, the MTF curves of the aerial image formed using different retro-reflectors are compared using the proposed method.

Mast cell hyperactivity underpins the development of oxygen-induced retinopathy.

Mast cells are classically thought to play an important role in protection against helminth infections and in the induction of allergic diseases; however, recent studies indicate that these cells also contribute to neovascularization, which is critical for tissue remodeling, chronic inflammation, and carcinogenesis. Here, we demonstrate that mast cells are essential for sprouting angiogenesis in a murine model of oxygen-induced retinopathy (OIR). Although mouse strains lacking mast cells did not exhibit retinal neovascularization following hypoxia, these mice developed OIR following infusion of mast cells or after injection of mast cell tryptase (MCT). Relative hypoxia stimulated mast cell degranulation via transient receptor potential ankyrin 1. Subsequent surges in MCT stimulated retinal endothelial cells to produce monocyte chemotactic protein-1 (MCP1) and angiogenic factors, leading to sprouting angiogenesis. Mast cell stabilizers as well as specific tryptase and MCP1 inhibitors prevented the development of OIR in WT mice. Preterm infants with early retinopathy of prematurity had markedly higher plasma MCT levels than age-matched infants without disease, suggesting mast cells contribute to human disease. Together, these results suggest therapies that suppress mast cell activity should be further explored as a potential option for preventing eye diseases and subsequent blindness induced by neovascularization.

A Case of Congenital Folliculitis Caused by Pseudomonas aeruginosa in a Preterm Neonate.

Intrauterine infections are associated with life-threatening neonatal conditions such as sepsis, intracranial hemorrhage, and chronic lung disease. Herein we present a case of generalized congenital folliculitis caused by Pseudomonas aeruginosa in a preterm neonate of 27 weeks gestational age successfully treated with antibiotics. Folliculitis is an important manifestation of intrauterine P. aeruginosa infection, and prompt, effective treatment is crucial to ensuring a good prognosis.

Subcutaneous fat necrosis after selective head cooling in an infant.

Hypoxic-ischemic encephalopathy in neonates causes irreversible damage to tissue and organs and results in multiple organ failure and poor outcome. Therapeutic hypothermia is the most effective therapy in neonates with hypoxic-ischemic encephalopathy. We report here a case of subcutaneous fat necrosis (SCFN) after therapeutic hypothermia by selective head cooling. Selective head cooling was provided for 72 h after birth. SCFN developed on the patient's cheeks and back at the age of 21 days. Thus, SCFN may be caused by selective head cooling, similarly to whole-body cooling.

Serum cytokine and chemokine profiles in neonates with meconium aspiration syndrome.

OBJECTIVES: Various inflammatory cytokines and chemokines are thought to be associated with the pathophysiology of meconium aspiration syndrome. To clarify any such association, we compared various serum cytokine and chemokine profiles in patients with and without meconium aspiration syndrome. PATIENTS AND METHODS: Using a highly sensitive fluorescence microsphere method, 17 types of cytokines and chemokines in sera were measured in 11 neonatal patients with meconium aspiration syndrome, 16 neonatal patients without meconium aspiration syndrome, and 9 healthy children. RESULTS: The concentrations of 8 types of proinflammatory cytokines and chemokines were significantly higher in the meconium aspiration syndrome group than in healthy controls: interleukin-1beta, interleukin-6, interleukin-8, granulocyte-macrophage colony-stimulating factor, granulocyte colony-stimulating factor, interferon-gamma, macrophage inflammatory protein-1beta, and tumor necrosis factor-alpha. Six types of proinflammatory cytokines and chemokines were significantly higher in the meconium aspiration syndrome group than in the nonmeconium aspiration syndrome group: interleukin-6, interleukin-8, granulocyte-macrophage colony-stimulating factor, granulocyte colony-stimulating factor, interferon-gamma, and tumor necrosis factor-alpha. Serum concentrations of interleukin-10 (anti-inflammatory cytokine) in the meconium aspiration syndrome group were higher than those in both the nonmeconium aspiration syndrome group and healthy children group (P = .007 and 0.001, respectively). CONCLUSIONS: Most types of proinflammatory cytokines and chemokines in sera of neonates with meconium aspiration syndrome were higher than those without meconium aspiration syndrome, giving support to the suggestion that elevated levels are associated with the pathogenesis of meconium aspiration syndrome.

Elevation of high-mobility group box 1 concentration in asphyxiated neonates.

BACKGROUND: In asphyxiated neonates, abnormal proinflammatory cytokine/chemokine production may be induced. High-mobility group box 1 (HMGB-1) protein is a new type of proinflammatory cytokine that induces abnormal inflammatory responses involving proinflammatory cytokine production. However, the physiological significance of HMGB-1 in asphyxia is poorly understood. OBJECTIVES: We aimed to evaluate whether serum HMGB-1 levels were changed in asphyxia by measuring the serum concentration of HMGB-1 in both asphyxiated and normally delivered neonates at birth. METHODS: Using enzyme-linked immunosorbent assay, we measured the concentration of HMGB-1 in sera obtained from 53 asphyxiated neonates and 32 normally delivered neonates immediately after birth. RESULTS: The serum concentrations of HMGB-1 in asphyxiated neonates were significantly higher than those in normally delivered neonates without asphyxia (p = 0.033). CONCLUSION: We suggest that the elevation of HMGB-1 might be associated with abnormal inflammatory responses involving the excessive production of proinflammatory cytokines in neonates with asphyxia.

Effect of meconium on the rate of in vitro subtype conversion of swine pulmonary surfactant.

UNLABELLED: The interactions between pulmonary surfactant and meconium have been previously reported, however, no prior study has paid attention to the effect of meconium on the extracellular surfactant metabolism. We studied the effect of meconium on the rate of surfactant subtype conversion from surface-active large surfactant aggregates to inactive small surfactant aggregates using the in vitro surface area cycling method. Human meconium was added to a suspension of large surfactant aggregates isolated from swine lung lavage fluid and the mixture was cycled in a capped polystyrene tube at 37 degrees C. The conversion rate from large to small surfactant aggregates was dependent upon the amount of meconium added. By sufficiently increasing the surfactant concentration, meconium could not significantly affect the surfactant subtype conversion. The conversion rate was temperature-dependent and was slower at 4 degrees C. Heat treatment of meconium diminished the rate of conversion. The potent effect of meconium on surfactant subtype conversion appears to be related to an enzymatic protein containing a serine active site, since the conversion occurred at 37 degrees C and not at lower temperatures and the conversion was blocked in the presence of diisopropyl fluorophosphate. CONCLUSION: Our study suggests that meconium can accelerate surfactant subtype conversion. We believe that the increased rate of conversion caused by meconium is a new mechanism for surfactant inactivation that could occur with lung injuries associated with meconium aspiration syndrome.