Long-Axis In-Plane Approach Versus Short-Axis Out-of-Plane Approach for Ultrasound-Guided Central Venous Catheterization in Pediatric Patients: A Randomized Controlled Trial.

OBJECTIVES: The aim of this study was to compare the occurrence of posterior wall puncture between the long-axis in-plane and the short-axis out-of-plane approaches in a randomized controlled trial of pediatric patients who underwent cardiovascular surgery under general anesthesia. DESIGN: Prospective randomized controlled trial. SETTING: Operating room of Osaka Women's and Children's Hospital. PATIENTS: Pediatric patients less than 5 years old who underwent cardiovascular surgery. INTERVENTIONS: Ultrasound-guided central venous catheterization using the long-axis in-plane approach and short-axis out-of-plane approach. MEASUREMENTS AND MAIN RESULTS: The occurrence of posterior wall puncture was compared between the long-axis in-plane and short-axis out-of-plane approaches for ultrasound-guided central venous catheterization. Patients were randomly allocated to a long-axis group or a short-axis group and underwent ultrasound-guided central venous catheterization in the internal jugular vein using either the long-axis in-plane approach (long-axis group) or the short-axis out-of-plane approach (short-axis group). After exclusion, 97 patients were allocated to the long-axis (n = 49) or short-axis (n = 48) groups. Posterior wall puncture rates were 8.2% (4/49) and 39.6% (19/48) in the long-axis and short-axis groups, respectively (relative risk, 0.21; 95% CI, 0.076-0.56; p = 0.0003). First attempt success rates were 67.3% (33/49) and 64.6% (31/48) in the long-axis and short-axis groups, respectively (relative risk, 1.04; 95% CI, 0.78-1.39; p = 0.77). Overall success rates within 20 minutes were 93.9% (46/49) and 93.8% (45/48) in the long-axis and short-axis groups, respectively (relative risk, 0.99; 95% CI, 0.90-1.11; p = 0.98). CONCLUSIONS: The long-axis in-plane approach for ultrasound-guided central venous catheterization is a useful technique for avoiding posterior wall puncture in pediatric patients, compared with the short-axis out-of-plane approach.

Evaluation of the RBC Pig-a assay and the PIGRET assay using benzo[a]pyrene in rats.

The red blood cell (RBC) Pig-a assay has the potential to detect the in vivo mutagenicity of chemicals. Recently, use of the Pig-a assay with reticulocytes (the PIGRET assay) reportedly enabled the in vivo mutagenicity of chemicals to be detected earlier than using the RBC Pig-a assay. To evaluate whether the PIGRET assay is useful and effective as a short-term test, compared with the RBC Pig-a assay, we performed both assays using benzo[a]pyrene (BP), which is a well-known mutagen. BP was used to dose 8-week-old male rats orally at 0, 75.0, 150, and 300mg/kg administered as a single administration. Peripheral blood samples were then collected on days 0, 7, 14, and 28 after treatment and were used in both assays. In the treatment groups receiving 150mg/kg of BP or more, both the RBC Pig-a assay and the PIGRET assay detected the in vivo mutagenicity of BP. In the 300mg/kg treatment group, in which a significant increase in the mutant frequency (MF) was observed at all the sampling points using both the RBC Pig-a assay and the PIGRET assay, the reticulocyte (RET) Pig-a MF was higher than the RBC Pig-a MF on days 7 and 14 after treatment; nevertheless, the negative control RET Pig-a MF was comparable to the negative control RBC Pig-a MF. In addition, the RET Pig-a MF began to increase after day 7 and reached a maximum value on day 14 after treatment, whereas the RBC Pig-a MF increased continuously from day 7 until day 28 after treatment. These results indicate that the PIGRET assay has a higher sensitivity than the RBC Pig-a assay and that the PIGRET assay is useful for the earlier detection of the in vivo mutagenicity of chemicals, compared with the RBC Pig-a assay.

Comparison of abnormal isoform of prion protein in prion-infected cell lines and primary-cultured neurons by PrPSc-specific immunostaining.

We established abnormal isoform of prion protein (PrPSc)-specific double immunostaining using mAb 132, which recognizes aa 119-127 of the PrP molecule, and novel PrPSc-specific mAb 8D5, which recognizes the N-terminal region of the PrP molecule. Using the PrPSc-specific double immunostaining, we analysed PrPSc in immortalized neuronal cell lines and primary cerebral-neuronal cultures infected with prions. The PrPSc-specific double immunostaining showed the existence of PrPSc positive for both mAbs 132 and 8D5, as well as those positive only for either mAb 132 or mAb 8D5. This indicated that double immunostaining detects a greater number of PrPSc species than single immunostaining. Double immunostaining revealed cell-type-dependent differences in PrPSc staining patterns. In the 22 L prion strain-infected Neuro2a (N2a)-3 cells, a subclone of N2a neuroblastoma cell line, or GT1-7, a subclone of the GT1 hypothalamic neuronal cell line, granular PrPSc stains were observed at the perinuclear regions and cytoplasm, whereas unique string-like PrPSc stains were predominantly observed on the surface of the 22 L strain-infected primary cerebral neurons. Only 14 % of PrPSc in the 22 L strain-infected N2a-3 cells were positive for mAb 8D5, indicating that most of the PrPSc in N2a-3 lack the N-terminal portion. In contrast, nearly half PrPSc detected in the 22 L strain-infected primary cerebral neurons were positive for mAb 8D5, suggesting the abundance of full-length PrPSc that possesses the N-terminal portion of PrP. Further analysis of prion-infected primary neurons using PrPSc-specific immunostaining will reveal the neuron-specific mechanism for prion propagation.

Bacterial tracheobronchitis. A rare cause of adult airway stenosis.

Bacterial tracheobronchitis is a rare cause of airway stenosis in adults. This report describes a 73-year-old woman with a recent history of polysialadenitis, who presented with severe airway obstruction due to infection and stenosis of tracheal and bronchial tissue. Tissue culture of the bronchial mucosa showed growth of methicillin resistant Staphylococcus epidermidis (MRSE). Sputum culture showed growth of MRSE, Pseudomonas aeruginosa, Enterobacter cloacae and Enterococcus faecalis; the same organisms were cultured from the salivary glands. Tracheostomy and antibiotic therapy were effective in controlling the disease.

Partial ablation of porcine stratum corneum by argon-fluoride excimer laser to enhance transdermal drug permeability.

To enhance skin permeability to medicine, the argon-fluoride excimer laser (ArF laser) was used to partially ablate the stratum corneum. Skin permeability to dextran (20 kDa) was studied in the Yucatan micro-pig skin in vitro. The cumulative amount of dextran permeating across the full-thickness skin was not detected for 30 h in the unirradiated skin; we obtained up to 90.5 microg/cm2 in laser-irradiated skin. In the case where the total laser energy was kept constant at 7.1 J/cm2, permeability was mainly influenced by laser fluence rather than laser pulses. Many granular structures of about 2 microm were found on the stratum corneum surface of ablated skin. Size and density of these structures were changed according to irradiation conditions. Skin permeability may be estimated by these structural changes. Our partial stratum corneum ablation by ArF laser could be suitable for transdermal drug delivery.