Facklamia hominis bacteremia after transurethral resection of the prostate: a case report.

BACKGROUND: Transurethral resection of the prostate (TUR-P) is one of the most frequent routine procedures in urology. Because of the semisterile environment, postoperative infections, including sepsis, are a common complication, with Escherichia coli, Klebsiella spp., Proteus mirabilis or Enterococcus faecalis as frequently isolated pathogens. Facklamia hominis is a gram-positive, facultatively anaerobic, alpha-hemolytic, catalase-negative coccus that was first described in 1997. To date, only a few cases of infectious complications have been described. We report the first case of postoperative bacteremia due to Facklamia hominis after TUR-P. CASE PRESENTATION: An 82-year-old man developed fever only a few hours after elective TUR-P because of benign prostate syndrome. After cultivation of blood cultures, antibiotic therapy with ceftriaxone was intravenously administered and changed to oral cotrimoxazole before discharge of the afebrile patient. One anaerobic blood culture revealed Facklamia hominis. Under antibiotic therapy, the patient remained afebrile and showed no signs of infections during follow-up. CONCLUSIONS: Fever and bacteremia are frequent complications after TUR-P. This study is the first report of Facklamia hominis in a postoperative blood culture after TUR-P. To date, there are only a few reports of patients with infectious complications and isolation of Facklamia hominis in various patient samples. Because Facklamia hominis resembles viridans streptococci on blood agar analysis, this pathogen may often be misidentified. In this case identification of Facklamia hominis was possible with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. It has been postulated that Facklamia hominis might be a facultative pathogen and that its incidence will increase in the future.

Templated growth of carbon nanotubes with controlled diameters using organic-organometallic block copolymers with tailored block lengths.

Block copolymer thin films fabricated from polystyrene-polyferrocenylsilane (PS-b-PFS) block copolymers on silicon substrates were used as precursors of well-ordered, nanosized growth catalysts for carbon nanotubes (CNTs). The size of the catalytic domains was tuned by changing the molecular weight of the block copolymer, enabling control of the diameter of the CNTs grown from these substrates. CNT growth on catalytic substrates with larger organometallic domain sizes, using acetylene as a carbon source, resulted in enhanced amounts of CNT deposition compared to smaller PFS domains, which exhibited low catalytic activity. The inner and outer diameters of the multi-walled CNTs obtained were typically 8 and 16 nm, respectively, and were not influenced by the catalytic domain sizes. Various annealing strategies in inert or in hydrogen atmosphere were investigated. The use acetylene with an additional hydrogen flow as gas feed resulted in a significant increase in deposition on all PS-b-PFS decorated substrates. Under these conditions, the CNT diameters could be controlled by the catalyst domain sizes, resulting in decreasing diameters with decreasing domain sizes. Multiwalled CNTs with inner and outer diameters of 4 and 7 nm, respectively, and a narrow diameter distribution were obtained.

Fast immobilization of probe beads by dielectrophoresis-controlled adhesion in a versatile microfluidic platform for affinity assay.

The use of probe beads for lab-on-chip affinity assays is very interesting from a practical point of view. It is easier to handle and trap beads than molecules in microfluidic systems. We present a method for the immobilization of probe beads at defined areas on a chip using dielectrophoresis (DEP)-controlled adhesion. The method is fast, i.e., it takes between 10 and 120 s--depending on the protocol--to functionalize a chip surface at defined areas. The method is versatile, i.e., it works for beads with different types of probe molecule coatings. The immobilization is irreversible, i.e., the retained beads are able to withstand high flow velocities in a flow-through device even after the DEP voltage is turned off, thus allowing the use of conventional high-conductivity analyte buffers in the following assay procedure. We demonstrate the on-chip immobilization of fluorescent beads coated with biotin, protein A, and goat-antimouse immunoglobulin G (IgG). The number of immobilized beads at an electrode array can be determined from their fluorescence signal. Further, we use this method to demonstrate the detection of streptavidin and mouse IgG. Finally, we demonstrate the feasibility of the parallel detection of different analyte molecules on the same chip.