Neonatal gene transfer with a retroviral vector results in tolerance to human factor IX in mice and dogs

The effect of neonatal gene transfer on antibody formation was determined using a retroviral vector (RV) expressing human factor IX (hFIX). Normal mice from different strains injected intravenously with RV as newborns achieved therapeutic levels of hFIX without antibody production and were tolerant as adults to challenge with hFIX. Neonatal hemophilia B mice that received different amounts of RV achieved stable and dose-related expression of hFIX without anti-hFIX antibody formation. After protein challenge, antibody formation was markedly reduced for animals that expressed hFIX at levels higher than 14 ng/mL (0.3% of normal). However, antibodies developed for animals that received the lowest dose of RV and expressed hFIX at approximately 2 ng/mL before protein challenge. In dogs, neonatal injection of a high dose of RV resulted in 500 ng/mL hFIX in plasma without antibody formation. We conclude that neonatal gene transfer with RV does not induce antibody responses to hFIX in mice or dogs and that mice achieving levels greater than 3 x 10-10 M hFIX are usually tolerant to protein injection as adults. Low-dose gene therapy or frequent protein injections in the neonatal period might induce tolerance to subsequent injections of protein with a low risk for adverse effects.     

Elevation of activated protein C in synovial joints in rheumatoid arthritis and its correlation with matrix metalloproteinase 2

OBJECTIVE: To investigate the involvement of the anticoagulant serine protease activated protein C (APC) in tissue remodeling in rheumatoid arthritis (RA). METHODS: PC/APC, matrix metalloproteinase 2 (MMP-2), and MMP-9 were detected in synovial fluid by Western blotting, and their antigen levels were quantified by enzyme-linked immunosorbent assay in patients with osteoarthritis (OA) or RA. Enzymatic activity of MMP-2 was assayed using a specific fluorogenic substrate. We developed an improved assay to measure APC activity in synovial fluid utilizing a chromogenic substrate following immunoprecipitation with a specific PC/APC antibody. PC/APC and MMP-2 were localized by immunohistochemistry in RA, OA, and normal synovial tissues. RESULTS: Synovial fluid analysis demonstrated that APC is present in both RA and OA synovial fluid, with APC activity being markedly higher in RA (mean +/- SEM 462 +/- 112 ng/ml versus 136 +/- 42 ng/ml; P < 0.02). A correlation (r(2) = 0.61) was found between APC and MMP-2 activity levels in RA patients, but not in OA patients. Immunohistochemical studies of synovial sections showed colocalization of APC and MMP-2 in endothelial and synovial lining cells. Additionally, APC and MMP-2 coimmunoprecipitated with an anti-PC/APC antibody. CONCLUSION: Our results show, for the first time, that APC and MMP-2 are coordinately up-regulated and tightly bound in RA synovial fluid and colocalized in synovia. Their association suggests that APC may modulate MMP-2 activity in RA.     

Comparison of Fentanyl Versus Meperidine for Analgesia in Pediatric Gastrointestinal Endoscopy

This study compared the safety and efficacy of fentanyl and meperidine for analgesia in pediatric gastrointestinal endoscopy. In a double-blind, randomized trial, 24 patients (11 males) received either fentanyl (1 microg/kg) or meperidine (1 mg/kg). These analgesics were administered in unmarked syringes by an investigator who did not participate in the procedure or in the evaluation of the patient's sedation. There were 17 Caucasians and 7 African-Americans whose mean age was 10.4 +/- 4.4 years. Thirteen patients received meperidine and 11 received fentanyl. Midazolam was given to all patients as needed to provide sufficient sedation for the procedure. Study subjects underwent EGD (n = 17) or colonoscopy (n = 7). There were no differences as assessed by patient, endoscopist, or assistant for tolerance, discomfort, procedure ease, recovery time, complications, heart rate, blood pressure, or oxygen saturation. We conclude that meperidine and fentanyl are equally effective in providing analgesia for pediatric gastrointestinal endoscopy.     

Motility of Pseudomonas aeruginosa contributes to SOS-inducible biofilm formation

DNA-damaging antibiotics such as ciprofloxacin induce biofilm formation and the SOS response through autocleavage of SOS-repressor LexA in Pseudomonas aeruginosa. However, the biofilm-SOS connection remains poorly understood. It was investigated with 96-well and lipid biofilm assays. The effects of ciprofloxacin were examined on biofilm stimulation of the SOS mutant and wild-type strains. The stimulation observed in the wild-type in which SOS was induced was reduced in the mutant in which LexA was made non-cleavable (LexAN) and thus SOS non-inducible. Therefore, the stimulation appeared to involve SOS. The possible mechanisms of inducible biofilm formation were explored by subproteomic analysis of outer membrane fractions extracted from biofilms. The data predicted an inhibitory role of LexA in flagellum function. This premise was tested first by functional and morphological analyses of flagellum-based motility. The flagellum swimming motility decreased in the LexAN strain treated with ciprofloxacin. Second, the motility-biofilm assay was performed, which tested cell migration and biofilm formation. The results showed that wild-type biofilm increased significantly over the LexAN. These results suggest that LexA repression of motility, which is the initial event in biofilm development, contributes to repression of SOS-inducible biofilm formation.     

Non-invasive prenatal testing for single gene disorders: exploring the ethics

Non-invasive prenatal testing for single gene disorders is now clearly on the horizon. This new technology offers obvious clinical benefits such as safe testing early in pregnancy. Before widespread implementation, it is important to consider the possible ethical implications. Four hypothetical scenarios are presented that highlight how ethical ideals of respect for autonomy, privacy and fairness may come into play when offering non-invasive prenatal testing for single gene disorders. The first scenario illustrates the moral case for using these tests for ‘information only'', identifying a potential conflict between larger numbers of women seeking the benefits of the test and the wider social impact of funding tests that do not offer immediate clinical benefit. The second scenario shows how the simplicity and safety of non-invasive prenatal testing could lead to more autonomous decision-making and, conversely, how this could also lead to increased pressure on women to take up testing. In the third scenario we show how, unless strong safeguards are put in place, offering non-invasive prenatal testing could be subject to routinisation with informed consent undermined and that woman who are newly diagnosed as carriers may be particularly vulnerable. The final scenario introduces the possibility of a conflict of the moral rights of a woman and her partner through testing for single gene disorders. This analysis informs our understanding of the potential impacts of non-invasive prenatal testing for single gene disorders on clinical practice and has implications for future policy and guidelines for prenatal care.     

Outcomes of a type 2 diabetes education program adapted to the cultural contexts of Saudi women: A pilot study

Objective:

To explore the outcomes of a pilot intervention of a type 2 diabetes (T2D) education program, based on international standards, and adapted to the cultural and religious contexts of Saudi women.

Methods:

This study is an experiment of a pilot intervention carried out between August 2011 and January 2012 at the primary health clinics in Dammam. Women at risk of or diagnosed with T2D (N=35 including dropouts) were assigned to one of 2 groups; an intervention group participated in a pilot intervention of T2D education program, based on international standards and tailored to their cultural and religious contexts; and a usual care group received the usual care for diabetes in Saudi Arabia. Outcomes included blood glucose, body composition, 6-minute walk distance, life satisfaction, quality of life, and diabetes knowledge. The intervention group participated in a focus group of their program experience. Data analysis was based on mixed methods.

Results:

Based on 95% confidence interval comparisons, improvements were noted in blood sugar, 6-minute walk distance, quality of life, and diabetes knowledge in participants of the intervention group. They also reported improvements in lifestyle-related health behaviors after the education program.

Conclusion:

Saudi women may benefit from a T2D education program based on international standards and adapted to their cultural and religious contexts.Saudi women have a higher prevalence of obesity than men, which increases their risk of type 2 diabetes (T2D).1 The reporting of diabetes is higher in women compared to men in all provinces of Saudi Arabia.1 Diabetes education programs in Saudi Arabia do not target people at risk of diabetes with emphasis on diabetes prevention and feasible changes to lifestyle behaviors.2 Scientific evidence suggests that diabetes education programs based on international standards of lifestyle behaviors, are more effective when tailored to the cultures and religions of targeted groups.3-6 The aim of this study was to explore the outcomes of a pilot intervention of a T2D education program based on international standards and adapted to the cultural and religious contexts of Saudi women. Specifically, whether such a program can impact health outcomes (for example, physical health measures, diabetes knowledge, life satisfaction, and health-related quality of life, diabetes knowledge) in comparison with the usual care of T2D in Saudi Arabia.