Validity of performance scales for disability assessment in multiple sclerosis

Researchers increasingly use self-reported health status assessments, but these require validation. Performance Scales (PS) is a self-report measure for multiple sclerosis (MS)-associated disability, assessing mobility, bowel/bladder, fatigue, sensory, vision, cognition, spasticity and hand function. The criterion validity of the total PS score was established using the Expanded Disability Status Scale (EDSS), but the construct and criterion validity of the individual subscales have not been established. We assessed the criterion and construct validity of the PS subscales. Forty-four patients with MS completed PS, and these criterion measurements: neurological examination (EDSS), the Multiple Sclerosis Functional Composite (MSFC), contrast acuity testing, and the Multiple Sclerosis Quality of Life Inventory. We assessed criterion and construct validity with Spearman rank correlations between PS subscales and the other measurements. PS correlated with the MSFC (r=-0.58, P<0.0001). The mobility, hand, vision, fatigue and bladder subscales correlated with their criterion measures (r=0.59-0.77, P<0.0001). The sensory subscale correlated weakly with the sensory functional system score (r=0.39, P=0.01 ), and the cognitive subscale did not correlate with the PASAT (r=-0.17, P=0.26). This study supports the criterion and construct validity of PS overall, and its mobility, hand, vision, fatigue, and bladder subscales. Further assessment of the cognitive, sensory and spasticity subscales is needed.

A comparison of various respiratory system models based on parameter estimates from impulse oscillometry data

Impulse oscillometry offers an advantage over spirometry when conducting pulmonary function tests. Not only does it require minimal patient cooperation, it provides useful data in a form amenable to engineering methods. In particular, the data can be used to obtain parameter estimates for electric circuit-based models of the respiratory system, which can in turn aid the detection and diagnosis of various diseases/pathologies. Of the six models analyzed during this study, the DuBois model and a newly proposed extended RIC model seem to provide the most robust parameter estimates for our entire data set of 106 subjects with various respiratory ailments such as asthma and chronic obstructive pulmonary disease. Such a diagnostic approach, relying on estimated parameter values, may require additional measures to ensure proper identification of diseases/pathologies but the preliminary results are promising.

From tolerance to autoimmunity: is there a risk in early life vaccination?

The potential for vaccines to act as triggers of autoimmune reactions has received much recent attention. Such an association is very poorly defined mechanistically, but may potentially involve epitope mimicry between vaccinal and self antigen, or the immuno-stimulatory effects of vaccine adjuvant. If such reactions occur, they are more likely to involve adults than infants in early life, as a reflection of the immunological immaturity of the newborn. There has been a recent focus in immunology on the link between innate and adaptive immunity provided by dendritic cells and the range of Toll-like receptors (TLRs) that are the point of first contact of these cells with microbial antigen. These interactions appear to determine the nature of the subsequent adaptive immune response and whether it may be mediated by Th1, Th2, Th17 or T regulatory populations. TLR interactions may also be significant in the induction of vaccinal immunity and agonists of these receptors are being developed as potential vaccine adjuvants. There are differences in cytokine production of adult and newborn dendritic cells, and these differences must be considered in the application of such novel adjuvants to products intended for either age group.

Translational mini-review series on Toll-like receptors: Toll-like receptor ligands as novel pharmaceuticals for allergic disorders

Characterization of the Toll-like receptor (TLR) family and associated signalling pathways provides a key molecular basis for our understanding of the relationship between exposure to microbial products and susceptibility to immune-mediated disorders. Indeed, ligation of TLR controls innate and adaptive immune responses by inducing synthesis of pro- as well as anti-inflammatory cytokines and activation of effector as well as regulatory lymphocytes. TLRs are therefore considered as major targets for the development of vaccine adjuvants, but also of new immunotherapies. Herein, we review the potential of TLR ligands as a novel class of pharmaceuticals for the prevention or treatment of allergic disorders.

Effect of changing the age criteria for blood donors

BACKGROUND AND OBJECTIVES

The upper age limit for allogeneic blood donation varies among countries and blood operators. We assessed the impact of the removal of the upper age limit for donation in Canada from December 2004 to January 2006.

MATERIALS AND METHODS

Starting in December 2004, regular donors were permitted to continue whole blood or apheresis donation past their 71st birthday, provided an annual external medical assessment was performed by their family physician. Regular donors aged from 70 to 74 were sent a letter about the change in criteria, and encouraged to continue donations. Rates of donor adverse reactions and deferrals were calculated for these donors and donors in other age groups.

RESULTS

In the 13-month period following implementation of the new criteria, 961 (54%) of regular donors who had received a letter initiated a medical inquiry, and 862 inquiries were completed and returned to Canadian Blood Services. In 98% of cases, the donors' family physician approved ongoing donation. Of the 659 donors who presented to donate, 93% successfully donated. There was only one moderate/severe donor reaction out of 3137 donor attendances for donors aged 71 and older. This rate was not statistically different from the rate in the overall donor population. No donors were deferred for high-risk activities or had positive infectious disease test results.

CONCLUSION

Regular blood donors may safely continue to donate past their 71st birthday. Extra steps in the donation process, such as an external medical inquiry, may not be necessary.

N-Acetylcysteine derivative inhibits procoagulant activity of human islet cells

AIMS/HYPOTHESIS

The early loss of beta cells after islet cell transplantation has been attributed in part to blood coagulation at the implant site. Tissue factor expressed by beta cells and contaminating duct cells is considered to activate this process. Here, we investigated the ability of N-acetyl-L-cysteine to suppress the in vitro procoagulant activity of duct cells and human islet cell preparations.

MATERIALS AND METHODS

The effects of Nacystelyn, a salt derivative of N-acetyl-L-cysteine, were first assessed on procoagulant activity induced in human plasma by recombinant tissue factor, human primary duct cells or human islet cell preparations. The influence of Nacystelyn on clot formation, platelet counts and D-dimers were measured in a whole blood tubing loop model. Human beta cell viability and insulin synthesis after Nacystelyn treatment were assessed to exclude cytotoxicity of Nacystelyn.

RESULTS

Nacystelyn efficiently inhibited the procoagulant activity of human recombinant tissue factor, primary duct cells and human islet cell preparations at clinically relevant concentrations without cellular toxicity.

CONCLUSIONS/INTERPRETATION

Nacystelyn is a pharmaceutical candidate to reduce early beta cell loss related to tissue factor-dependent coagulation after islet transplantation.

The interleukin-12 family: new players in transplantation immunity?

Since several years ago, interleukin (IL)-12 is known to be responsible for the differentiation of naive CD4+ T cells into type 1 helper T cells producing interferon-gamma. Recently, two other cytokines of the IL-12 family, IL-23 and IL-27, were shown to play key roles in experimental autoimmune disorders mediated by Th17 cells, a novel pro-inflammatory CD4+ T-cell subset secreting IL-17. As our knowledge of IL-12 family members is rapidly growing and changing, it will be important to specify their involvement in the induction and regulation of allograft rejection in animal models as well as in clinical settings. Herein, we review key features of cytokines belonging to the IL-12 family and discuss their potential relevance to transplantation immunity.

[From discovery to innovation: the example of hypereosinophilic syndrome]

Biomedical research is extremely productive so that each day new discoveries reveal novel (mechanisms and) molecular pathways of diseases. However, the number of innovative therapies approved each year by regulatory authorities is decreasing. The causes of this "innovation breakdown" are multiple and should be explored both in academic institutions and in the industrial world. New initiatives are underway in the Walloon Region to improve this situation, such as the setting up of the BioWin Health Cluster gathering pharmaceutical and biotechnology enterprises and university laboratories. This new vision of the partnership between academia and the private sector should be based on strong fundamental research activities. We illustrate this concept by discussing recent advances in the diagnosis and treatment of the hypereosinophilic syndrome.

Survival After Disseminated Invasive Aspergillosis in a Multivisceral Transplant Recipient

Disseminated invasive aspergillosis is a serious and potentially lethal infectious complication of immunosuppressed individuals, including transplant recipients. We report here a successfully treated case of disseminated Aspergillus fumigatus infection involving the lungs, brain, and endocardium in a multivisceral transplant recipient. In addition to supportive measures, the patient was aggressively treated with a combination of three antifungal agents, and all immunosuppression was significantly lowered with close observation for rejection. After 3 months of therapy, the patient cleared the fungal infection, made a full recovery of his cerebral function, and was discharged to a rehabilitation facility.

Is there an optimal time for laparoscopic cholecystectomy in acute cholecystitis?

BACKGROUND

Laparoscopic cholecystectomy (LC) is safe in acute cholecystitis, but the exact timing remains ill-defined. This study evaluated the effect of timing of LC in patients with acute cholecystitis.

METHODS

Prospective data from the hospital registry were reviewed. All patients admitted with acute cholecystitis from June 1994 to January 2004 were included in the cohort.

RESULTS

Laparoscopic cholecystectomy was attempted in 1,967 patients during the study period; 80% were women, mean patient age was 44 years (range, 20-73 years). Of the 1,967 LC procedures, 1,675 were successful, and 292 were converted to an open procedure (14%). Mean operating time for LC was 1 h 44 min (SD +/- 50 min), versus 3 h 5 min (SD +/- 79 min) when converted to an open procedure. Average postoperative length of stay was 1.89 days (+/- 2.47 days) for the laparoscopic group and 4.3 days (+/- 2.2 days) for the conversion group. No clinically relevant differences regarding conversion rates, operative times, or postoperative length of stay were found between patients who were operated on within 48 h compared to those patients who were operated on post-admission days 3-7.

CONCLUSIONS

The timing of laparoscopic cholecystectomy in patients with acute cholecystitis has no clinically relevant effect on conversion rates, operative times, or length of stay.

Plethysmography and impulse oscillometry assessment of tiotropium and ipratropium bromide; a randomized, double-blind, placebo-controlled, cross-over study in healthy subjects

AIMS

Spirometry, plethysmography and impulse oscillometry (IOS) measure different aspects of lung function. These methods have not been compared for their ability to assess long- and short-acting anticholinergic agents. We therefore performed a double-blind, placebo-controlled, four-way cross-over study in 30 healthy subjects.

METHODS

Single doses of tiotropium bromide (Tio) 54 and 18 mcg, ipratropium bromide (IB) 40 mcg and placebo were administered. Specific conductance (sGaw), total lung capacity (TLC), inspiratory capacity (IC) and residual volume (RV) were measured using plethysmography, while IOS measured resistance (R5-25) and reactance (RF and X5). Pulmonary function was measured for 26 h post dose.

RESULTS

Tio caused significant improvements in sGaw, forced expiratory voume in 1 s (FEV(1)), maximum mid-expiratory flow (MMEF) and R5-R25 at time points up to 26 h, with no clear differences between doses. IB improved the same parameters, but only up to 8 h. The weighted mean change (0-24 h) caused by Tio 54 mcg compared with placebo for FEV(1) was 240 ml (95% confidence interval 180, 300), while for sGaw the ratio of geometric means (Tio compared with placebo) was 1.35 (1.28, 1.41). Neither drug caused consistent statistically significant changes in RF, forced vital capacity, TLC or IC over 26 h. RV was significantly improved from 8 to 24 h by Tio 54 mcg only.

CONCLUSIONS

In addition to spirometry, IOS resistance measurements and sGaw can distinguish between the effects of long- and shortacting anticholinergic effects in healthy subjects.

Nephrotoxicity of uranyl acetate: effect on rat kidney brush border membrane vesicles

Since the Gulf war exposure to depleted uranium, a known nephrotoxic agent, there is a renewed interest in the toxic effects of uranium in general and its mechanism of nephrotoxicity which is still largely unknown in particular. In order to investigate the mechanism responsible for uranium nephrotoxicity and the therapeutic effect of urine alkalization, we utilized rat renal brush border membrane vesicles (BBMV). Uranyl acetate (UA) caused a decrease in glucose transport in BBMV. The apparent K (i) of uranyl was 139+/-30 microg uranyl/mg protein of BBMV. Uranyl at 140 microg/mg protein of BBMV reduced the maximal capacity of the system to transport glucose [V (max) 2.2+/-0.2 and 0.96+/-0.16 nmol/mg protein for control and uranyl treated BBMV (P<0.001), respectively] with no effect on the apparent K (m) (1.54+/-0.33 and 1.54+/-0.51 mM for control, and uranyl treated BBMV, respectively). This reduction in V(max) is at least partially due to a decrease in the number of sodium-coupled glucose transporters as apparent from the reduction in phlorizin binding to the uranyl treated membranes, V (max) was reduced from 247+/-13 pmol/mg protein in control BBMV to 119+/-3 pmol/mg protein in treated vesicles (P<0.001). The pH of the medium has a profound effect on the toxicity of UA on sodium-coupled glucose transport in BBMV: higher toxicity at neutral pH (around pH 7.0), and practically no toxicity at alkaline pH (7.6). This is the first report showing a direct inhibitory dose and pH dependent effect of uranyl on the glucose transport system in isolated apical membrane from kidney cortex.

Predominance of type 1 CD4+ T cells in human abdominal aortic aneurysm

The functional repertoire of T cells in abdominal aortic aneurysm (AAA) and the exact nature of aortic wall adaptive cellular immune responses still remains a matter of debate. In this study, we sought to determine whether type 1 or type 2 responses occur predominantly in human aneurysmal aortic lesions. We first examined the phenotype and cytokine secretion profile of T lymphocytes freshly isolated from aneurysmal aortic wall for comparison with their circulating counterparts using flow cytometry. We found that both populations of infiltrating CD4(+) and CD8(+)T cells displayed a unique activated memory phenotype. In addition, we identified the presence in human aneurysmal aortic lesion of CD4(+)T cells producing high levels of interferon (IFN)-gamma but not interleukin (IL)-4, reflecting their type 1 nature. Quantitative analysis of cytokine gene expression confirmed increased IFN-gamma transcript levels in infiltrating cells compared to controls. We next analysed aortic wall responses using LightCycler-based quantitative real-time reverse transcription-polymerase chain reaction. Compared to control non-diseased aortic samples, we demonstrated that whole AAA tissues exhibited high mRNA levels of IFN-gamma but not IL-4. Overexpression of the transcription factor T-bet in the absence of significant GATA-3 expression further assessed the type 1 polarization of aortic wall immune responses. These findings indicate that type 1 CD4(+)T cells predominate in human AAA lesions. This study has important implications for the pathogenesis of aneurysm disease. Through the production of IFN-gamma, T cells may indeed contribute to orchestrate extracellular matrix remodelling.

Circulating angiogenic proteins in trisomy 13

OBJECTIVE

Women who are carrying a trisomy 13 fetus are more prone to develop preeclampsia. Excess circulating soluble fms-like tyrosine kinase-1 has been implicated recently in the pathogenesis of preeclampsia. Since the fms-like tyrosine kinase-1/soluble fms-like tyrosine kinase-1 gene is located on chromosome 13q12, we hypothesized that the extra copy of this gene in trisomy 13 may lead to excess circulating soluble fms-like tyrosine kinase-1, reduced free placental growth factor level, and increased soluble fms-like tyrosine kinase-1/placental growth factor ratio. This may then contribute to the increased risk of preeclampsia that has been observed in these patients. Our objective was to characterize the maternal circulating angiogenic proteins in trisomy 13 pregnancies.

STUDY DESIGN

Maternal serum samples of trisomy 13, 18, 21 and normal karyotype pregnancies were obtained from first and second trimester screening programs. We chose 17 cases of trisomy 13 that were matched for maternal age, freezer storage time, and parity with 85 normal karyotype control samples. Additionally, 20 cases of trisomy 18 and 17 cases of trisomy 21 were included. Cases and control samples were assayed for levels of soluble fms-like tyrosine kinase-1 and placental growth factor by enzyme-linked immunosorbent assay in a blinded fashion. Because of the skewed distributions of soluble fms-like tyrosine kinase-1 and placental growth factor, nonparametric analytic techniques were used, and the results are reported as median and ranges.

RESULTS

In early pregnancy trisomy 13 cases and control samples, the median circulating soluble fms-like tyrosine kinase-1/placental growth factor ratios were 17.0 (range, 1.2-61.3) and 6.7 (range, 0.8-62.9), respectively (P = .003). The median soluble fms-like tyrosine kinase-1/placental growth factor ratios in trisomy 18 and 21 were 4.8 (range, 0.9-53.9) and 5.1 (range, 1.0-18.1), which were not significantly different than the control samples. Furthermore, the differences between trisomy 13 and control samples were more pronounced in the second trimester specimens than in the specimens from the first trimester.

CONCLUSION

These data suggest that alterations in circulating angiogenic factors may be involved intimately in the pathogenesis of preeclampsia in trisomy 13. A larger clinical study that measures these factors longitudinally and correlates them with pregnancy outcomes is needed to further establish the link between trisomy 13, altered angiogenic factors, and preeclampsia.

T cell-mediated immune responses in human newborns: ready to learn?

Infections with intracellular pathogens are often more severe or more prolonged in young infants suggesting that T cell-mediated immune responses are different in early life. Whereas neonatal immune responses have been quite extensively studied in murine models, studies of T cell-mediated immunity in human newborns and infants are scarce. Qualitative and quantitative differences when compared with adult immune responses have been observed but on the other hand mature responses to certain vaccines and infectious pathogens were demonstrated during the postnatal period and even during foetal life. Herein, we review the evidence suggesting that under appropriate conditions of stimulation, protective T cell-mediated immune responses could be induced by vaccines in early life.

Unexpected effects of viral interleukin-10-secreting dendritic cells in vivo: preferential inhibition of TH2 responses

Viral interleukin (IL)-10 (vIL-10) has been widely described as an immunoregulatory cytokine that does not possess the T-cell costimulatory activities of cellular IL-10; it was therefore believed to be a more potent tolerogenic mediator. The immunosuppressive properties of this cytokine are partly attributed to its capacity to render dendritic cells (DCs) unable to undergo full maturation and to activate T cells. We reported here that myeloid DCs retrovirally transduced with vIL-10 had an impaired production of IL-12 and a decreased expression of MHC class II molecules but had minor defects in costimulatory molecule expression and no alteration on CCR5 and CCR7 expression. In mixed leukocyte reaction, vIL-10-transduced C57BL/6 bm12 (MHC class II mismatch) DCs had a reduced capacity to stimulate C57BL/6 wild-type CD4+ T-cell proliferation. We show that bm12 vIL-10-transduced DC administration in CD8-/- C57BL/6 mice promoted IFN-gamma production, down-regulated TH2-type cytokine production, and did not induce skin graft tolerance. These findings suggest that vIL-10-transduced DC may surprisingly facilitate Th1-type inflammatory responses in vivo.