Extended interval dosing of natalizumab in multiple sclerosis

BACKGROUND

Natalizumab (NTZ), a monoclonal antibody to human α4β1/β7 integrin, is an effective therapy for multiple sclerosis (MS), albeit associated with progressive multifocal leukoencephalopathy (PML). Clinicians have been extending the dose of infusions with a hypothesis of reducing PML risk. The aim of the study is to evaluate the clinical consequences of reducing NTZ frequency of infusion up to 8 weeks 5 days.

METHODS

A retrospective chart review in 9 MS centres was performed in order to identify patients treated with extended interval dosing (EID) regimens of NTZ. Patients were stratified into 3 groups based on EID NTZ treatment schedule in individual centres: early extended dosing (EED; n=249) every 4 weeks 3 days to 6 weeks 6 days; late extended dosing (LED; n=274) every 7 weeks to 8 weeks 5 days; variable extended dosing (n=382) alternating between EED and LED. These groups were compared with patients on standard interval dosing (SID; n=1093) every 4 weeks.

RESULTS

17% of patients on SID had new T2 lesions compared with 14% in EID (p=0.02); 7% of patients had enhancing T1 lesions in SID compared with 9% in EID (p=0.08); annualised relapse rate was 0.14 in the SID group, and 0.09 in the EID group. No evidence of clinical or radiographic disease activity was observed in 62% of SID and 61% of EID patients (p=0.83). No cases of PML were observed in EID group compared with 4 cases in SID cohort.

CONCLUSIONS

Dosing intervals up to 8 weeks 5 days did not diminish effectiveness of NTZ therapy. Further monitoring is ongoing to evaluate if the risk of PML is reduced in patients on EID.

Aspergillus oryzae-Saccharomyces cerevisiae Consortium Allows Bio-Hybrid Fuel Cell to Run on Complex Carbohydrates

Consortia of Aspergillus oryzae and Saccharomyces cerevisiae are examined for their abilities to turn complex carbohydrates into ethanol. To understand the interactions between microorganisms in consortia, Fourier-transform infrared spectroscopy is used to follow the concentrations of various metabolites such as sugars (e.g., glucose, maltose), longer chain carbohydrates, and ethanol to optimize consortia conditions for the production of ethanol. It is shown that with proper design A. oryzae can digest food waste simulants into soluble sugars that S. cerevisiae can ferment into ethanol. Depending on the substrate and conditions used, concentrations of 13% ethanol were achieved in 10 days. It is further shown that a direct alcohol fuel cell (FC) can be coupled with these A. oryzae-enabled S. cerevisiae fermentations using a reverse osmosis membrane. This “bio-hybrid FC” continually extracted ethanol from an ongoing consortium, enhancing ethanol production and allowing the bio-hybrid FC to run for at least one week. Obtained bio-hybrid FC currents were comparable to those from pure ethanol—water mixtures, using the same FC. The A. oryzae–S. cerevisiae consortium, coupled to a bio-hybrid FC, converted food waste simulants into electricity without any pre- or post-processing.

Bone mineral density and biochemical markers of bone metabolism in ankylosing spondylitis

OBJECTIVE

To determine (1) bone mineral density (BMD) of the axial and appendicular skeleton in men with moderate and severe ankylosing spondylitis (AS), and (2) associations between BMD and bone metabolism variables.

METHODS

Nineteen men with AS and 19 healthy male controls were evaluated for osteoporosis by dual energy x-ray absorptiometry in both the hip and the lateral and posterior-anterior (PA) projections of the lumbar spine. Calcium homeostasis was evaluated by measuring minerals, calcitropic hormones, and markers of remodeling. Total testosterone levels were also measured.

RESULTS

Osteopenia was noted in both the hip and spine of the subjects with AS. The lateral projection of L3 was a more sensitive indicator of the vertebral BMD compared to the PA projection. Calciuin homeostasis and testosterone levels were normal in subjects with AS. In most subjects, markers of bone formation and resorption were normal.

CONCLUSION

BMD of subjects with AS is decreased, in spite of normal calcium homeostasis and bone remodeling indices.

Immune monitoring of blood in heart transplant recipients: application of flow cytometry

In this study, we review the utility of peripheral blood lymphocyte evaluation using commercially available monoclonal antibodies in the diagnosis of rejection or infection in 27 patients undergoing allograft heart transplantation. Double-color staining methods employing fluorescein isothiocyanate (FITC) and phycoerythrin (PE) allowed identification of a variety of lymphocyte subsets and determination of activation or proliferation of lymphocytes. All patients also underwent regular endomyocardial biopsy procedures. A total of 30 rejection episodes were diagnosed by endomyocardial biopsy. The results of immune monitoring profile (IMP) of lymphocytes and endomyocardial biopsies were concordant 76% of the time. Discrepancies were most common when the biopsy showed only mild rejection. The false-positive rate with serial IMP was less than 1%. The IMP was also useful in distinguishing between infection, especially cytomegalovirus infection, and rejection. General guidelines for utilizing IMP in transplant recipients are presented.