Dissociation of factor VIII in the presence of proteolytic inhibitors.

When gel filtration of factor VIII is performed with buffers of high ionic strength (1.0 M NaCl or 0.25 M CaCl2), the procoagulant activity elutes with proteins of relatively low molecular weight. It has been suggested that in the presence of proteolytic inhibitors, the procoagulant activity would appear at the void volume. To test this hypothesis, chromatography with buffers of high ionic strength was performed in the presence of benzamidine hydrochloride, soy bean trypsin inhibitor, heparin, DFP, and aprotinin. Under all of these conditions, the procoagulant activity continued to elute with proteins of low molecular weight. Similar findings were obtained after chromatographing cryoprecipitate prepared from the plasma of a normal subject who had received heparin. Thus, at present there is no direct evidence to suggest that proteolysis is involved in the dissociation of factor VIII by buffers of high ionic strength.     

Protein Fraction with Immunogenic Potential and Low Toxicity Isolated from the Cell Wall of Neisseria meningitidis Group B

Several fractions were extracted from the cell envelope (CE) of Neisseria meningitidis group B and characterized with regard to their morphology, antigenicity, protein composition, and toxicity. Whole bacterial cells were suspended in a medium of low ionic strength and disrupted in a French pressure cell. The crude CE thus obtained were separated into cell membrane (CM) enriched and cell wall (CW) enriched fractions on sucrose density gradients. In addition, CM and CW fractions were separated from CE on the basis of differential solubility in the nonionic detergent, Triton X-100. The Triton-insoluble fraction, containing primarily CW components, was further treated with a mixture of Triton and ethylenediaminetetraacetic acid, which was shown to remove additional protein and most of the lipopolysaccharide. Electron microscope examination of the various fractions revealed typical unit membrane structures in the case of CM, or large, open segments in the case of CW. The Triton-insoluble and especially the Triton-ethylenediaminetetraacetic acid-insoluble fractions consisted of small vesicular structures. All fractions, except the Triton-soluble fraction, when assayed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, were shown to contain one major protein component accounting for more than 50% of the total. Sera from rabbits immunized with the various fractions formed precipitin lines in immunodiffusion tests against the homologous and some of the heterologous fractions. High-titer bactericidal antibodies were also demonstrated in these sera when tested against the homologous strains. Toxicity studies in rats sensitized with lead acetate indicate that the level of contamination of Triton-insoluble/Triton-ethylenediaminetetraacetic acid-insoluble fractions with lipopolysaccharide was significantly smaller than that of the other fractions.     

Attempted replication of reported chronic obstructive pulmonary disease candidate gene associations

Case-control studies have successfully identified many significant genetic associations for complex diseases, but lack of replication has been a criticism of case-control genetic association studies in general. We selected 12 candidate genes with reported associations to chronic obstructive pulmonary disease (COPD) and genotyped 29 polymorphisms in a family-based study and in a case-control study. In the Boston Early-Onset COPD Study families, significant associations with quantitative and/or qualitative COPD-related phenotypes were found for the tumor necrosis factor (TNF)-alpha -308G>A promoter polymorphism (P < 0.02), a coding variant in surfactant protein B (SFTPB Thr131Ile) (P = 0.03), and the (GT)(31) allele of the heme oxygenase (HMOX1) promoter short tandem repeat (P = 0.02). In the case-control study, the SFTPB Thr131Ile polymorphism was associated with COPD, but only in the presence of a gene-by-environment interaction term (P = 0.01 for both main effect and interaction). The 30-repeat, but not the 31-repeat, allele of HMOX1 was associated (P = 0.04). The TNF -308G>A polymorphism was not significant. In addition, the microsomal epoxide hydrolase "fast" allele (EPHX1 His139Arg) was significantly associated in the case-control study (P = 0.03). Although some evidence for replication was found for SFTPB and HMOX1, none of the previously published COPD genetic associations was convincingly replicated across both study designs.     

The juxtamembrane wedge negatively regulates CD45 function in B cells

CD45 is a receptor-like protein tyrosine phosphatase highly expressed on all nucleated hematopoietic cells. We previously generated mice containing a point mutation in the juxtamembrane wedge of CD45. Demonstrating the critical negative regulatory function of the wedge, the CD45 E613R mutation led to a lymphoproliferative disorder (LPD) and a lupus-like autoimmune syndrome. Here we show the central role of B cells in this phenotype. Genetic elimination of B cells, but not T cells, ablates the LPD. In contrast to CD45-deficient B cells, the E613R mutation generates hyperresponsive B cells. Comparison of CD45-deficient and CD45 E613R mice reveals dichotomous effects of these mutations on B cell development. Together, the results support a role for CD45 as a rheostat, with both positive and negative regulatory functions, that fine-tunes the signal transduction threshold at multiple checkpoints in B cell development.     

Ethical issues in the use of genetic information in the workplace: a review of recent developments

PURPOSE OF REVIEW: In the wake of the Human Genome Project, the pace of genetic discovery has quickened. New genetic tests and other molecular technology have had immediate and wide relevance to American and European workers. These tests have the potential to provide improved workplace safety and protect workers' health, but they also carry the risk of genetic discrimination including loss of employment, promotion, insurance and health care. Ethical safeguards are necessary if the benefits are to outweigh the adverse consequences of genetics in the workplace. RECENT FINDINGS: This review examines the major policy statements issued in Europe and the USA from 2000 to 2005 pertaining to genetic issues in occupational health. Recent findings stress that genetic testing can only be utilized with worker consent and that the workers should control access to genetic information. Such testing is only justified when the information is required to protect the safety of the worker or a third party. The progress of occupational genetic technology should not be permitted to shift the responsibility for a safe working environment from the employer to the employee. Genetic discrimination in all forms is neither supported scientifically nor warranted ethically. SUMMARY: Increasingly, occupational physicians and clinicians treating workers will be faced with potentially stigmatizing genetic information and there is an urgent need for education and research to expand and implement the recommendations of major governmental and professional policy statements.     

The Carers' Needs Assessment for Dementia (CNA-D): development, validity and reliability

BACKGROUND: A variety of interventions are available to support the caregivers of dementia patients. For the purposes of service planning, we developed an instrument to assess the needs of these caregivers and to determine whether needs are met. The reliability and validity of this new instrument was also investigated. METHODS: The development of the Carers' Needs Assessment for Dementia (CNA-D), was based on in-depth interviews and a focus group. The combined inter-rater and test-retest reliability was investigated among 45 dementia caregivers. Correlations of the CNA-D with the Zarit Burden Inventory were used to analyze concurrent validity. Content validity was investigated by performing a separate survey among 40 caregivers and 40 professionals. RESULTS: The CNA-D is a semi-structured research interview including 18 problem areas. For each problem area, the CNA-D offers several possible interventions. The relevance of the problem areas and the interventions (content validity) was confirmed by most of the study participants. Significant positive associations were found between the total score of the Zarit Burden Inventory and the number of problems and the number of unmet needs according to the CNA-D. The agreement between the interviewers was "excellent" (kappa above 0.75) in 73.7% of the problem areas and in 69.9% of the interventions. CONCLUSIONS: The CNA-D is a valid and reliable instrument for comprehensively assessing the needs of dementia caregivers.     

Admissibility of false-confession testimony: know thy standard

The reliability of confessions is subject to a variety of factors, some of which give rise to expert testimony. To the degree that prosecutors construe the determination of reliability as an objective standard, they may attempt to bar testimony. Moreover, when the testimony is theoretical rather than clinical, there are additional challenges. Depending on jurisdiction, the admissibility of expert testimony on whether a confession was knowing, intelligent, and voluntary is subject to a legal threshold such as the Frye or Daubert standard. The authors review a 2002 New Jersey Superior Court ruling that illustrates the forces that shape the admissibility of confessions.     

A multisite randomized trial of the effects of physician education and organizational change in chronic asthma care: cost-effectiveness analysis of the Pediatric Asthma Care Patient Outcomes Research Team II (PAC-PORT II)

BACKGROUND: A decision to implement innovative disease management interventions in health plans often requires evidence of clinical benefit and financial impact. The Pediatric Asthma Care Patient Outcomes Research Team II trial evaluated 2 asthma care strategies: a peer leader-based physician behavior change intervention (PLE) and a practice-based redesign called the planned asthma care intervention (PACI). OBJECTIVE: To estimate the cost-effectiveness of the interventions. METHODS: This was a 3-arm, cluster randomized trial conducted in 42 primary care practices. A total of 638 children (age range, 3-17 years) with mild to moderate persistent asthma were followed up for 2 years. Practices were randomized to PLE (n = 226), PACI (n = 213), or usual care (n = 199). The primary outcome was symptom-free days (SFDs). Costs included asthma-related health care utilization and intervention costs. RESULTS: Annual costs per patient were as follows: PACI, USD 1292; PLE, USD 504; and usual care, USD 385. The difference in annual SFDs was 6.5 days (95% confidence interval [CI], -3.6 to 16.9 days) for PLE vs usual care and 13.3 days (95% CI, 2.1-24.7 days) for PACI vs usual care. Compared with usual care, the incremental cost-effectiveness ratio was USD 18 per SFD gained for PLE (95% CI, USD 5.21-dominated) and USD 68 per SFD gained for PACI (95% CI, USD 37.36-361.16). CONCLUSIONS: Results of this study show that it is possible to increase SFDs in children and move organizations toward guideline recommendations on asthma control in settings where most children are receiving controller medications at baseline. However, the improvements were realized with an increase in the costs associated with asthma care.