Cytosolic proteins contribute to surface plasminogen recruitment of Neisseria meningitidis.

Plasminogen recruitment is a common strategy of pathogenic bacteria and results in a broad-spectrum surface-associated protease activity. Neisseria meningitidis has previously been shown to bind plasminogen. In this study, we show by several complementary approaches that endolase, DnaK, and peroxiredoxin, which are usually intracellular proteins, can also be located in the outer membrane and act as plasminogen receptors. Internal binding motifs, rather than C-terminal lysine residues, are responsible for plasminogen binding of the N. meningitidis receptors. Recombinant receptor proteins inhibit plasminogen association with N. meningitidis in a concentration-dependent manner. Besides binding purified plasminogen, N. meningitidis can also acquire plasminogen from human serum. Activation of N. meningitidis-associated plasminogen by urokinase results in functional activity and allows the bacteria to degrade fibrinogen. Furthermore, plasmin bound to N. meningitidis is protected against inactivation by alpha(2)-antiplasmin.

Genetic mechanisms for loss of encapsulation in polysialyltransferase-gene-positive meningococci isolated from healthy carriers.

Encapsulated Neisseria meningitidis expressing serogroups A, B, C, W-135, or Y remain a major cause of morbidity and mortality globally. This bacterium is, however, a common commensal inhabitant of the human nasopharynx that causes disease infrequently. Isolates obtained from healthy carriers are frequently unencapsulated and therefore essentially avirulent. The lack of capsule can be due to inactivation of capsule synthesis genes by a variety of genetic mechanisms, or the absence of capsule synthesis genes. Analysis of inactivation mechanisms was undertaken in a diverse but representative set of 166 acapsulate meningococci isolated from carriage that possessed capsule synthesis genes. Slipped strand mispairing in the siaA and siaD genes of the capsule synthesis locus was observed in 39 isolates. Insertion sequence (IS) elements (IS1016-like, IS1106 and IS1301) were responsible for the loss of encapsulation in 46 isolates. Irreversible gene silencing events (insertions, deletions, base exchanges) were found in 47 isolates. Two non-synonymous mutations were identified in close vicinity of the putative active site of the UDP-N-acetylglucosamine 2-epimerase encoded by the siaA gene. The mechanisms for loss of encapsulation were not associated with particular meningococcal genotypes. There was no evidence for successive gene silencing events in the capsule genes, suggesting that the irreversible inactivation events observed were the result of short-term, within-host evolution. These observations are consistent with the postulate that particular meningococcal clonal complexes are associated with possession of a capsule and that this association is important for transmission success.

Small cell carcinoma of the lung: an "updated" overview.

OBJECTIVES: To review the current status and recent advances, and ongoing research efforts related to the diagnosis, staging, and treatment of small cell lung cancer (SCLC). DATA SOURCES: Review articles, book chapters, research studies, and abstracts relating to SCLC. CONCLUSIONS: SCLC is the most aggressive type of lung cancer with many patients having widespread disease at the time of diagnosis. It is the most treatment responsive lung cancer to both chemotherapy and radiotherapy, with aggressive chemotherapy the cornerstone of treatment. Yet, the survival rate is limited. Several new drugs have been found to be active and it is hoped that they will lead to improved results. IMPLICATIONS FOR NURSING PRACTICE: An understanding of the prognostic factors, staging, treatment modalities, and new therapies for SCLC will help nurses assist patients to make educated decisions about the potential risks and benefits of their therapeutic options.

Administrative issues in ambulatory oncology care.

The major priority of the ambulatory care nurse administrator is to negotiate the role changes that have occurred in ambulatory care and allow nurses to practice developed skills and collaborate with other health care professionals. Defining the scope of practice, developing standards of care, staffing requirements, budgeting, and developing a quality assurance program are major responsibilities of the ambulatory nurse administrator.

Susceptibility of Planorbarius metidjensis from Portugal and Spain to Schistosoma bovis from Salamanca, Spain.

The susceptibility of Planorbarius metidjensis from Portugal and Salamanca (Spain) to Schistosoma bovis from Salamanca was studied. The degree of susceptibility as measured by positivity rate, number of cercariae, pre-patent period and survival rate, showed that P. metidjensis from Portugal and Spain are very susceptible to S. bovis from Salamanca. The role of P. metidjensis as a host of S. haematobium is questioned and further studies are shown to be necessary. To determine if the disease exists in Portugal, the bovine and snail populations on the border with Salmanaca and Algarve are beginning to be screened.