Antibacterial effects of nano-imprinted moth-eye film in practical settings.

BACKGROUND: Recent studies report that surfaces displaying micrometer- or nanometer-sized undulating structures exhibit antibacterial effects. In previous work, we described the use of an advanced nanofabrication technique to generate an artificial biomimetic Moth-eye film by coating a polyethylene terephthalate (PET) film with nanoscale moth-eye protrusions made from a hydrophilic resin. This moth-eye film exhibited enhanced antibacterial effects in in vitro experiments. The aim of the present study was to verify the antibacterial efficacy of the Moth-eye film in practical environments. MATERIALS AND METHODS: The antibacterial effects of three types of film (Moth-eye film, Flat film, and PET film) were compared. Sample films were pasted onto hand washing basins at the testing locations. After several hours, bacteria were collected from the surface of the sample films with one of three kinds of culture media stamper (to permit identification of bacterial species). The stampers were incubated for 48 hours at 35°C, and the numbers of colonies were counted. RESULTS AND DISCUSSION: The number of common bacteria including E. coli and S. aureus obtained from the Moth-eye film was significantly lower than those from the PET film (p<0.05) and Flat film at 1 hour (p<0.05). This study found that the Moth-eye film showed a long-term (6h) antibacterial effect and the Moth-eye structure (PET coated with nanoscale cone-shaped pillars) demonstrated a physical antibacterial effect from earlier time points. Therefore, the Moth-eye film appears to have potential general-purpose applications in practical environments.

Antibacterial effects of the artificial surface of nanoimprinted moth-eye film.

The antibacterial effect of a nanostructured film, known as "moth-eye film," was investigated. The moth-eye film has artificially formed nano-pillars, consisting of hydrophilic resin with urethane acrylate and polyethylene glycol (PEG) derivatives, all over its surface that replicates a moth's eye. Experiments were performed to compare the moth-eye film with a flat-surfaced film produced from the same materials. The JIS Z2801 film-covering method revealed that the two films produced a decrease in Staphylococcus aureus and Esherichia coli titers of over 5 and 3 logs, respectively. There was no marked difference in the antibacterial effects of the two surfaces. However, the antibacterial effects were reduced by immersion of the films in water. These results indicated that a soluble component(s) of the resin possessed the antibacterial activity, and this component was identified as PEG derivatives by time-of-flight secondary ion mass spectrometry (TOF-SIMS) and Fourier transform infrared spectroscopy (FT-IR). When a small volume of bacterial suspension was dropped on the films as an airborne droplet model, both films showed antibacterial effects, but that of the moth-eye film was more potent. It was considered that the moth-eye structure allowed the bacteria-loaded droplet to spread and allow greater contact between the bacteria and the film surface, resulting in strong adherence of the bacteria to the film and synergistically enhanced bactericidal activity with chemical components. The antibacterial effect of the moth-eye film has been thus confirmed under a bacterial droplet model, and it appears attractive due to its antibacterial ability, which is considered to result not only from its chemical make-up but also from physical adherence.

Pelvic Discontinuity Caused by Acetabular Overreaming during Primary Total Hip Arthroplasty.

Intraoperative acetabular fracture is a rare complication of primary total hip arthroplasty (THA), typically occurring during impaction of the cementless acetabular component. Here we report an unusual case of pelvic discontinuity caused by overreaming of the acetabulum during primary THA. Restoration of posterior columnar continuity was achieved with an autologous fibular graft and a reconstruction plate. Wall defects and cavitary defects were reconstructed with metal mesh and femoral head allograft, followed by placement and fixation of a Kerboull-type acetabular reinforcement device. Previous reports of acetabular fracture during THA have indicated that it has a relatively good prognosis without extensive treatment. However, to our knowledge, there has been no report of pelvic discontinuity necessitating acetabular reconstruction surgery as an intraoperative complication of primary THA.

Cervical spinal cord injury without bony injury: a multicenter retrospective study of emergency and critical care centers in Japan.

BACKGROUND: To demonstrate the clinical characteristics of patients with cervical cord injury (CCI) without bony injury in Japan. METHODS: Retrospective review of 127 patients with CCI without bony injury treated between January 2003 and October 2005 at 11 institutions. RESULTS: Prevalence of CCI without bony injury was 32.2% among all CCIs and 0.81% among all blunt traumas. Mean age was 60.4 years (range, 19-90 years), with 104 patients (82%) > or = 46 years old (older group). The major mechanism of injury among younger patients (< 46 years) was traffic injuries (39%), whereas minor falls (44%) predominated in older patients. High-energy mechanisms of injury were significantly more common for younger patients (35% versus 15%, p = 0.041). Mean injury severity score, abbreviated injury score for the head and Glasgow coma scale on admission were 17.2 +/- 4.7, 0.6 +/- 0.9, and 14.2 +/- 2.1, respectively. Incomplete CCI occurred in 88.7%. On plain cervical spine radiography, spinal canal stenosis and spondylosis or ossification of the posterior longitudinal ligament were more frequent in older patients than in younger patients (43% vs. 13%, p = 0.008; 54% vs. 17%, p = 0.002, respectively). No abnormal findings were seen in 52% of younger patients. CONCLUSION: CCI without bony injury occurred more frequently in this study population than previously reported. Degenerative changes and spinal canal stenosis represent important risk factors for developing CCI without bony injury and the present results suggest that this injury may occur in younger adults during high-energy injuries in the absence of pre-existing cervical spine disease.

Volvulus of the gall bladder diagnosed by ultrasonography, computed tomography, coronal magnetic resonance imaging and magnetic resonance cholangio-pancreatography.

A 54-year-old woman was admitted to our hospital with the complaint of right upper quadrant pain. Upon physical examination the vital signs of the patient were within normal ranges. Ultrasonography and computed tomography (CT) examination of the abdomen was obtained, which demonstrated a large dilatated cystic structure, measuring approximately 68.6 mm multiply 48.6 mm, with marked distension and inflammation. Additionally, the enhanced CT was characterized by the non-enhanced wall of the gallbladder. As the third examination in this study, magnetic resonance imaging (MRI), namely coronal MRI and magnetic resonance cholangio-pancreatogra (MRCP), were performed. The MRCP demonstrated a dilatation of the gallbladder but detected no neck of the gallbladder. Simple cholecystectomy was performed. Macroscopic findings included a distended and gangrenous gallbladder, and closer examination revealed a counterclockwise torsion of 360 degrees on the gallbladder mesentery. Coronal MRI and MRCP showing characteristic radiography may be useful in making a definitive diagnosis.