Methicillin-resistant Staphylococcus aureus genotyping using a small set of polymorphisms

The aim of this study was to identify a set of genetic polymorphisms that efficiently divides methicillin-resistant Staphylococcus aureus (MRSA) strains into groups consistent with the population structure. The rationale was that such polymorphisms could underpin rapid real-time PCR or low-density array-based methods for monitoring MRSA dissemination in a cost-effective manner. Previously, the authors devised a computerized method for identifying sets of single nucleoticle polymorphisms (SNPs) with high resolving power that are defined by multilocus sequence typing (MLST) databases, and also developed a real-time PCR method for interrogating a seven-member SNP set for genotyping S. aureus. Here, it is shown that these seven SNPs efficiently resolve the major MRSA lineages and define 27 genotypes. The SNP-based genotypes are consistent with the MRSA population structure as defined by eBURST analysis. The capacity of binary markers to improve resolution was tested using 107 diverse MRSA isolates of Australian origin that encompass nine SNP-based genotypes. The addition of the virulence-associated genes cna, pvl and bbplsdrE, and the integrated plasmids pT181, p1258 and pUB110, resolved the nine SNP-based genotypes into 21 combinatorial genotypes. Subtyping of the SCCmec locus revealed new SCCmec types and increased the number of combinatorial genotypes to 24. It was concluded that these polymorphisms provide a facile means of assigning MRSA isolates into well-recognized lineages.

Stage is not a reliable indicator of tumor volume in non-small cell lung cancer: a preliminary analysis of the trans-tasman radiation oncology group 99-05 database

Background: Tumor volume has been shown to be a prognostic factor for the response of some tumors to radiotherapy. TNM stage has prognostic value for patients treated surgically for non-small cell lung cancer (NSCLC), but its value is less clear for patients treated by nonsurgical means. This may be because tumor size is not a consistent determinant of T stage or stage group. As part of the preliminary analyses for the Trans-Tasman Radiation Oncology Group 99-05 study, the authors performed this analysis to determine to what extent stage reflects tumor volume. Methods: In this prospective multicenter observational study, patients had to have histologically proven NSCLC, no evidence of disease beyond the primary site or thoracic lymph nodes, and been planned for radical radiotherapy with or without chemotherapy. Tumor volume measurements were based on computed tomography-based treatment planning images. Results: Four hundred four patients were available for analysis. There was a strong correlation between (log) maximum tumor diameter and (log) tumor volume (r = 0.93, p < 0.001). Although there was a highly significant trend of increasing volume with increasing T stage and stage group, when tumors were categorized into four groups according to increasing volume, there was only 55% concordance with T stage and 67% concordance with stage group. Conclusions: There is limited correlation between tumor size and disease stage in patients with NSCLC. This justifies documentation and investigation of size as a potential prognostic factor independent of stage. Maximum tumor diameter may be an adequate substitute for volume as a measurement of size.

Small firm internationalisation; understanding the practice through an interpretive approach

The unit of analysis in firm internationalisation studies is the firm but this overlooks the importance of the individual in the internationalisation process. An evaluation of the dominant theories of firm internationalisation highlights an implicit dualistic ontology, that is, where research subject and object are considered to be separate and independent. Implications of this assumption are discussed after reviewing the dominant literatures on firm internationalisation. An alternative approach is proposed that focuses on understanding internationalisation of the firm from an individual practitioner’s perspective. It is suggested that contemporary firm internationalisation research has been hindered by its basic assumptions and its inherent researcher orientation. An interpretive phenomenographic approach is proposed as a means of achieving a first-person, practitioner’s perspective of the process of firm internationalisation, specifically in the context of the small firm. Preliminary interpretations of interviews with owners/managers of small Australian wineries are presented.

Examining the role of networking capability in small and medium firm internationalization

While research on SME internationalization has increased, there remains a lack of relevant theory on the SME internationalization process. The literature reports that small firms overcome their resource poverty-based constraints to internationalization by developing network relationships. Networking enables SMEs to acquire much needed internationalization process knowledge, and knowledge for the development of innovative products and services for this internationalization. However, networking activity has not yet been conceptualized and measured as a competitive capability in internationalization research. Drawing on the capability-based theory of competitive strategy, this paper conjectures that internationally entrepreneurial SMEs build and nurture distinctive networking capabilities, enabling them to acquire new knowledge. These learning capabilities enable them to pursue innovation thereby facilitating nternationalization. Data from Australian firms largely supports the conceptual framework. Implications for theory and practice are presented.