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Pediatrics International | 2008

Complications of percutaneously inserted central venous catheters in Japanese neonates

Yasushi Ohki; Yukihiro Yoshizawa; Masayuki Watanabe; Makoto Kuwashima; Akihiro Morikawa

Background: To determine institutional policies concerning percutaneously inserted central venous catheter (PICC) utilization and also frequencies of complications such as pericardial effusion (PCE), cardiac tamponade (CT), pleural effusion, ascites, venous thrombosis, and catheter removal difficulties.


Neonatology | 2009

Hepatocyte growth factor treatment improves alveolarization in a newborn murine model of bronchopulmonary dysplasia.

Yasushi Ohki; Hiroo Mayuzumi; Kenichi Tokuyama; Yukihiro Yoshizawa; Hirokazu Arakawa; Hiroyuki Mochizuki; Akihiro Morikawa

Background: Bronchopulmonary dysplasia (BPD) is thought to be one form of developmental arrest of the lung. Hepatocyte growth factor (HGF) participates in normal lung growth and in lung regeneration. Objectives: The purpose of this study is to investigate whether HGF can improve alveolarization and attenuates functional abnormalities of a murine model of BPD induced by hyperoxia. Methods: Three-day-old CD-1 mice were exposed to 90% of oxygen or room air (control group) for 7 days. These animals were then kept in room air for the next 7 days. Recombinant human (rh) HGF (100 μg/g b.w., divided 3 times, rhHGF group) or vehicle (vehicle group) was administered intraperitoneally during hyperoxia. On day 17, the pulmonary function test and bronchial hyperresponsiveness (BHR) were examined. Mean linear intercepts (MLI) were measured as parameters of alveolarization. Cell renewal (on day 10) and vascularization of the lung were also evaluated. Results: Exposure to hyperoxia induced increased airway resistance and BHR. These animals showed a severely simplified alveolar structure, increased MLI, decreased cell renewal (16.1 ± 2.4 vs. 29.6 ± 2.4%, p < 0.05), and decreased vascularization (15.1 ± 0.3 vs. 18.4 ± 1.5 vessels/hpf, p < 0.05, vehicle vs. control group, respectively). rhHGF treatment during exposure to hyperoxia significantly reduced all of these changes (27.9 ± 1.7%, 18.2 ± 0.5 vessels/hpf for cell renewal and vascularization, respectively; all values are p < 0.05 against vehicle animals). Conclusion: HGF partially protects against the inhibition of alveolarization and improves functional abnormality in the hyperoxia-induced neonatal mice model of BPD.


Neonatology | 2007

Maturational Changes in Skin Color of Japanese Newborn Infants

Masayuki Watanabe; Yasushi Ohki; Yukihiro Yoshizawa; Yoshinari Inoue; Kenichi Tokuyama; Akihiro Morikawa

Background/Objective: The skin color of newborn infants is subjectively observed to change, depending upon their gestational age. We evaluated the relationship between neonatal skin color and gestational age by employing an objective method. Methods: Using a tristimulus photocolorimeter, L*, a*, and b* were examined as the parameters of skin color in Japanese newborn infants (Commission Internationale de l’Eclairage L*a*b* color space). The following items were examined: (1) the reproducibility of the measurements; (2) the time course of the values during the first 24 h after birth, and (3) the relationship with the gestational age. The gestational age of these infants had been determined by measuring their crown-rump length during fetal periods. Results: Reliability and validity of the measurements were satisfactory for all parameters. However, a* and b* fluctuated widely during the first 24 h. By contrast, L* was stable between 3 and 24 h after birth. L* measured during these periods directly correlated with the gestational age (r = 0.843, p < 0.0001). Conclusions: Because L* represents lightness or darkness, our results suggest that the skin color changes from black to white with maturation. L* may be a helpful parameter for the evaluation of the gestational age of newborn infants.


Neonatology | 2009

Periventricular Echodensity Measured with the Integrated Backscatter System: From a Qualitative Assessment to a Quantitative Approach

Yukihiro Yoshizawa; Masayuki Watanabe; Yasushi Ohki; Kenichi Tokuyama; Hiroo Mayuzumi; Yukiko Takahashi; Akihiro Morikawa

Background: The degree of periventricular white matter echodensity in preterm infants has been utilized as a sign of the early ultrasonographic appearance of periventricular leukomalacia, and this has been called periventricular echodensity (PVE). Objectives: The aim of this study was to quantitatively measure PVE utilizing a new method which is called calibrated integrated backscatter (calibrated IB). Methods: Eighty-eight preterm infants (extremely low birth weight infants, n = 17; very low birth weight infants, n = 26; low birth weight infants, n = 45) without any CNS abnormality were enrolled. IB is the returned sound pressure against supersonic waves sent from an ultrasonographic machine. The IB of the choroid plexus and periventricular white matter in the subrolandic area were measured on a parasagittal cerebral image. The degree of PVE was defined by subtracting the IB of the choroid plexus from that of the periventricular white matter in the subrolandic area (calibrated IB of PVE). Results: The intraobserver and interobserver correlations were both excellent (between 0.87 and 0.98 as correlation coefficients). There was a trend for the calibrated IB of PVE to decrease in accordance with time after birth, with a significant difference in very low birth weight and low birth weight infants. Conclusions: The objectively measured brightness of PVE was comparable to that of the choroid plexus irrespective of the size of the infants. Measurement of the calibrated IB of PVE might be a reliable method to assess PVE.


Neonatology | 2009

Contents Vol. 95, 2009

Yasushi Ohki; Hiroo Mayuzumi; Kenichi Tokuyama; Yukihiro Yoshizawa; Hirokazu Arakawa; Hiroyuki Mochizuki; Akihiro Morikawa; Janez Babnik; Tore Curstedt; Henry L. Halliday; Mikko Hallman; Ola Didrik Saugstad; Christian P. Speer; Ingemar Ingemarsson; Otto Helve; Olli Pitkänen; Cecilia Janér; Sture Andersson; Jatinder Bhatia; Anjali Parish; Roger F. Soll; Judit Gyarmati; Margit Tökés-Füzesi; Gabor L. Kovacs; Valéria Gaál; Gabriella Vida; Tibor Ertl; Deborah L. Harris; Malcolm Battin; Chris E. Williams

S. Andersson, Helsinki E. Bancalari, Miami, Fla. G. Buonocore, Siena W.A. Carlo, Birmingham, Ala. V.P. Carnielli, Ancona W.J. Cashore, Providence, R.I. I.A. Choonara, Derby T. Curstedt, Stockholm O. Dammann, Boston, Mass. C. Dani, Florence B. Darlow, Christchurch P. Gluckman, Auckland M. Hallman, Oulu B. Jonsson, Stockholm S.E. Juul, Seattle, Wash. A. Llanos, Santiago R.J. Martin, Cleveland, Ohio C.J. Morley, Cambridge J. Neu, Gainesville, Fla. P.C. Ng, Hong Kong M. Obladen, Berlin A.G.S. Philip, Palo Alto, Calif. M. Post, Toronto E. Saliba, Tours O.D. Saugstad, Oslo B. Schmidt, Philadelphia, Pa. E. Shinwell, Rehovot J. Smith, Cape Town B. Sun, Shanghai H. Togari, Nagoya F. van Bel, Utrecht N. Vain, Buenos Aires M. Vento Torres, Valencia M. Weindling, Liverpool J.A. Widness, Iowa City, Iowa Fetal and Neonatal Research


Neonatology | 2009

Contents Vol. 96, 2009

Riikka Turunen; Outi Vaarala; Irmeli Nupponen; Eero Kajantie; Sanna Siitonen; Aulikki Lano; Heikki Repo; Sture Andersson; U. Herberg; Diane Goltz; Henning Weiss; U. Gembruch; Johannes Breuer; Michael Obladen; Yukihiro Yoshizawa; Masayuki Watanabe; Yasushi Ohki; Kenichi Tokuyama; Hiroo Mayuzumi; Yukiko Takahashi; Akihiro Morikawa; Marty O. Visscher; Mauricio Odio; Teresa Taylor; Tamina White; Shelly Sargent; Linda Sluder; Louise Smith; Teresa Flower; Beth Mason

S. Andersson, Helsinki E. Bancalari, Miami, Fla. G. Buonocore, Siena W. Carlo, Birmingham, Ala. V.P. Carnielli, Ancona W.J. Cashore, Providence, R.I. I. Choonara, Derby T. Curstedt, Stockholm O. Dammann, Boston, Mass. C. Dani, Florence B. Darlow, Christchurch P.D. Gluckman, Auckland M. Hallman, Oulu B. Jonsson, Stockholm S.E. Juul, Seattle, Wash. A.J. Llanos, Santiago R.J. Martin, Cleveland, Ohio C.J. Morley, Cambridge J. Neu, Gainesville, Fla. P.C. Ng, Hong Kong M.W. Obladen, Berlin A.G.S. Philip, Sebastopol, Calif. M. Post, Toronto E. Saliba, Tours O.D. Saugstad, Oslo B. Schmidt, Philadelphia, Pa. E.S. Shinwell, Rehovot J. Smith, Tygerberg B. Sun, Shanghai H. Togari, Nagoya F. van Bel, Utrecht N. Vain, Buenos Aires M. Vento Torres, Valencia M. Weindling, Liverpool J.A. Widness, Iowa City, Iowa Fetal and Neonatal Research


Neonatology | 2009

24th International Workshop on Surfactant Replacement, Ljubljana, June 4–6, 2009

Yasushi Ohki; Hiroo Mayuzumi; Kenichi Tokuyama; Yukihiro Yoshizawa; Hirokazu Arakawa; Hiroyuki Mochizuki; Akihiro Morikawa; Janez Babnik; Tore Curstedt; Henry L. Halliday; Mikko Hallman; Ola Didrik Saugstad; Christian P. Speer; Ingemar Ingemarsson; Otto Helve; Olli Pitkänen; Cecilia Janér; Sture Andersson; Jatinder Bhatia; Anjali Parish; Roger F. Soll; Judit Gyarmati; Margit Tökés-Füzesi; Gabor L. Kovacs; Valéria Gaál; Gabriella Vida; Tibor Ertl; Deborah L. Harris; Malcolm Battin; Chris E. Williams


Neonatology | 2009

Subejct Index Vol. 96, 2009

Riikka Turunen; Outi Vaarala; Irmeli Nupponen; Eero Kajantie; Sanna Siitonen; Aulikki Lano; Heikki Repo; Sture Andersson; U. Herberg; Diane Goltz; Henning Weiss; U. Gembruch; Johannes Breuer; Michael Obladen; Yukihiro Yoshizawa; Masayuki Watanabe; Yasushi Ohki; Kenichi Tokuyama; Hiroo Mayuzumi; Yukiko Takahashi; Akihiro Morikawa; Marty O. Visscher; Mauricio Odio; Teresa Taylor; Tamina White; Shelly Sargent; Linda Sluder; Louise Smith; Teresa Flower; Beth Mason


Neonatology | 2009

Subject Index Vol. 95, 2009

Yasushi Ohki; Hiroo Mayuzumi; Kenichi Tokuyama; Yukihiro Yoshizawa; Hirokazu Arakawa; Hiroyuki Mochizuki; Akihiro Morikawa; Janez Babnik; Tore Curstedt; Henry L. Halliday; Mikko Hallman; Ola Didrik Saugstad; Christian P. Speer; Ingemar Ingemarsson; Otto Helve; Olli Pitkänen; Cecilia Janér; Sture Andersson; Jatinder Bhatia; Anjali Parish; Roger F. Soll; Judit Gyarmati; Margit Tökés-Füzesi; Gabor L. Kovacs; Valéria Gaál; Gabriella Vida; Tibor Ertl; Deborah L. Harris; Malcolm Battin; Chris E. Williams


日本周産期・新生児医学会雑誌 = Journal of Japan Society of Perinatal and Neonatal Medicine | 2006

Routine Practice and Complication on Percutaneously Inserted Central Venous Catheter in Neonates : A Nationwide Survey

Yasushi Ohki; Yukihiro Yoshizawa; Masayuki Watanabe; Akihiro Morikawa

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