A novel cell-adhesive scaffold material for delivering keratinocytes reduces granulation tissue in dermal wounds.

Novel peptide-conjugated chitosan membranes were fabricated and used to deliver keratinocytes to dermal wounds in mice. Three active peptides of 12 or 13 amino acids each, RLVSYNGIIFFLK (A5G27), ASKAIQVFLLAG (A5G33), and AGTFALRGDNPQG (A99) were selected from a cell-adhesive peptide library of laminin, a major constituent of basement membrane. The peptides were synthesized and coupled to chitosan membranes, and the resulting peptide-chitosan membranes were tested for keratinocyte attachment. Two of the peptides that bind to cell surface heparin-like receptors (A5G27 and A5G33) were found to promote strong keratinocyte attachment, whereas the one that binds to integrin (A99) was inactive. Subsequently, A5G27- and A5G33-chitosan membranes were tested as vehicles for keratinocyte delivery in a wound model. We found that keratinocytes were delivered into the full-thickness wound with either membrane. Using the A5G33-chitosan membrane, we further evaluated the activity of the delivered keratinocytes in wound healing. Immunohistochemistry for granulation tissue markers, including tenascin and alpha-smooth muscle actin, showed that keratinocyte delivery by the present peptide-chitosan membranes in the wound bed provided a favorable condition for keratinocyte migration along the wound surface and reduced granulation tissue formation.

Reconstruction of the umbilicus using a reverse fan-shaped flap.

The goal of the reconstruction for umbilical absence is to obtain a natural three-dimensional appearance of the umbilicus with minimal operative scarring. This paper presents two cases of umbilical reconstruction using a reverse fan-shaped flap. In both cases, the umbilicus was lost during surgical procedures on the abdominal wall when the patients were newborns. We performed this technique in both cases. This technique is simple and safe. With this technique, a permanent umbilical depth and ring can be obtained without any complications.

Oral antimicrobial susceptibilities of Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis isolates from Japanese children.

The minimum inhibitory concentrations (MICs) of 11 oral antibiotics were measured for 140 Streptococcus pneumoniae, 115 Haemophilus influenzae, and 46 Moraxella catarrhalis strains isolated from Japanese children. The antibiotics selected included a range of commonly prescribed agents together with a selection of new cefems and a penem. Cefditoren was most active against the highly penicillin resistant S. pneumoniae, beta-lactamase-producing H. influenzae and beta-lactamase-negative ampicillin-resistant H. influenzae. However, amoxycillin retained good activity against the penicillin-susceptible or -intermediately resistant S. pneumoniae (88.6%) and most of ampicillin-susceptible or -intermediately resistant H. influenzae (87.9%). We thus consider that amoxycillin remains a useful initial choice for the treatment of paediatric respiratory infections in Japan.

Incidences of nasopharyngeal colonization of respiratory bacterial pathogens in Japanese children attending day-care centers.

BACKGROUND: In Japan, many younger children attending day-care centers tend to frequently experience acute respiratory infections and prolonged otitis media. OBJECTIVES: To evaluate the carriage rate of respiratory bacterial pathogens in children attending day-care centers in our district. METHODS: Nasopharyngeal cultures of 156 healthy children between the ages of 1 month and 5 years were conducted at two day-care centers in Japan, in April 1999. The carriage rates of four major pathogens (Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis and Staphylococcus aureus) and the antibiotic susceptibilities of the isolates were examined. RESULTS: Streptococcus pneumoniae, H. influenzae, M. catarrhalis and S. aureus were detected in 94 (60.3%), 83 (53.2%), 54 (34.6%) and 28 (17.9%) children, respectively. A total of 141 (90.4%) children carried at least one pathogen among these four pathogens and 87 (55.8%) children carried more than one pathogen. Fifty-seven of the 94 (60.6%) S. pneumoniae isolates were penicillin-intermediately or highly resistant strains of S. pneumoniae (PISP/PRSP). Beta-lactamase producing H. influenzae was not detected. Twelve of the 28 (42.9%) S. aureus isolates were methicillin-resistant. The incidence of colonization by PISP/PRSP in children younger than 3 years (43/69, 62.3%) was significantly higher than that in children aged 3-5 years (14/87, 16.1%) (P < 0.0001). CONCLUSIONS: We conclude that the rates of colonization by respiratory bacterial pathogens, especially by antibiotic-resistant strains, were high in children attending day-care centers in our district, suggesting their horizontal spread among children in day-care centers. Considering that the majority of children attending day- care centers carried one or more of the bacterial pathogens, the judicious use of antimicrobials will be required to prevent the increase of antibiotic-resistant rates among the colonizing pathogens.