No abstract

A novel surface protein of the bacterial species Moraxella catarrhalis that displays a high affinity for IgD (MID) was solubilized in Empigen and isolated by ion exchange chromatography and gel filtration. The apparent molecular mass of monomeric MID was estimated to ∼200 kDa by SDS-PAGE. The mid gene was cloned and expressed in Escherichia coli. The complete mid nucleotide gene sequence was determined, and the deduced amino acid sequence consists of 2123 residues. The sequence of MID has no similarity to other Ig-binding proteins and differs from all previously described outer membrane proteins of M. catarrhalis. MID was found to exhibit unique Ig-binding properties. Thus, in ELISA, dot blots, and Western blots, MID bound two purified IgD myeloma proteins, four IgD myeloma sera, and finally one IgD standard serum. No binding of MID was detected to IgG, IgM, IgA, or IgE myeloma proteins. MID also bound to the surface-expressed B cell receptor IgD, but not to other membrane molecules on human PBLs. This novel Ig-binding reagent promises to be of theoretical and practical interest in immunological research.

Protein D (PD) is a highly conserved 42 kDa surface lipoprotein found in all Haemophilus influenzae, including nontypeable (NT) H. influenzae. PD is involved in the pathogenesis of respiratory tract infections, in the context of which it has been shown to impair ciliary function in a human nasopharyngeal tissue culture model and to augment the capacity to cause otitis media in rats. A likely mechanism indicating that PD is a virulence factor is its glycerophosphodiesterase activity, which leads to the release of phosphorylcholine from host epithelial cells. PD has been demonstrated to be a promising vaccine candidate against experimental NT H. influenzae infection. Rats vaccinated with PD cleared NT H. influenzae better after middle ear and pulmonary bacterial challenge, and chinchillas vaccinated with PD showed significant protection against NT H. influenzae-dependent acute otitis media. In a clinical trial involving children, PD was used as an antigenically active carrier protein in an 11-valent pneumococcal conjugate investigational vaccine; significant protection was achieved against acute otitis media not only caused by pneumococci but also caused by NT H. influenzae. This may have great clinical implications, because PD is the first NT H. influenzae antigen that has induced protective responses in humans.

The gene for protein D, a membrane-associated protein with specific affinity for human immunoglobulin D, was cloned from a nontypeable strain of Haemophilus influenzae. The gene was expressed in Escherichia coli

We describe four cases in Sweden of verified treatment failures of pharyngeal gonorrhoea with ceftriaxone (500 mg; n=3) or cefotaxime (500 mg; n=1) monotherapy. All the ceftriaxone treatment failures were caused by the internationally spreading multidrug-resistant gonococcal NG-MAST genogroup 1407 clone. Increased awareness of treatment failures is crucial particularly when antimicrobial monotherapy is used. Frequent test of cure and appropriate verification/falsification of suspected treatment failures, as well as implementation of recommended dual antimicrobial therapy are imperative.

No abstract

Nasal decolonization has a proven effect on the prevention of severe Staphylococcus aureus infections and the control of methicillin-resistant S. aureus (MRSA). However, rising rates of resistance to antibiotics highlight the need for new substances for nasal decolonization. LTX-109 is a broad-spectrum, fast-acting bactericidal antimicrobial drug for topical treatment, which causes membrane disruption and cell lysis. This mechanism of action is not associated with cross-resistance and has a low propensity for development of resistance. In the present study, persistent nasal MRSA and methicillin-sensitive S. aureus (MSSA) carriers were treated for 3 days with vehicle or with 1%, 2%, or 5% LTX-109. A significant effect on nasal decolonization was observed already after 2 days of LTX-109 treatment in subjects treated with 2% or 5% LTX-109 compared to vehicle (P < 0.0012 by Dunnett=s test). No safety issues were noted during the 9-week follow-up period. Minimal reversible epithelial lesions were observed in the nasal cavity. The systemic exposure was very low, with a maximum concentration of drug in plasma (C max ) at 1 to 2 h postdosing (3.72 to 11.7 ng/ml). One week after treatment initiation, LTX-109 was not detectable in any subject. Intranasal treatment of S. aureus with LTX-109 is safe and reduces the bacterial load already after a single day of treatment. Hence, LTX-109 has potential as a new and effective antimicrobial agent with a low propensity of resistance development that can prevent infections by MSSA/MRSA during hospitalization. (This study has been registered at ClinicalTrials.gov under registration no. NCT01158235.) N asal carriage of Staphylococcus aureus is considered a marker of extended skin carriage and colonization by S. aureus. The colonization is often asymptomatic, but most severe S. aureus infections are caused by endogenous strains from the patient (1-5).Persistent nasal colonization by S. aureus, including methicillin-resistant S. aureus (MRSA) strains, has shown to be a major risk factor for surgical-site (6) and renal dialysis (5, 7) infections. Such individuals have a substantially increased risk for S. aureus hospital-acquired infections (8), with up to as many as 11 to 22% of methicillin-sensitive and -resistant S. aureus carriers developing nosocomial infections during hospital admission (9). In addition, patients carrying S. aureus can be a source of transmission to noncarriers, which subsequently can lead to health care-related exogenous infections.The spread of S. aureus remains unquestionably a serious challenge in infection control in hospitals, and in an attempt to reduce the S. aureus infection rates, prevention programs aiming at decolonizing individual nasal S. aureus carriers have been implemented. The most well-established regimen recommended in several national guidelines (e.g., in the 1998 United Kingdom guideline and the upcoming U.S. CDC guideline) is using a combination of 5 to 7 days of treatment with nasal mupirocin ointment and chlorhexidine soap (4,5,(10)(11)(12...

No abstract