Assessing the value of spinal cord lesions in predicting development of multiple sclerosis in patients with clinically isolated syndromes

The purpose of this study was to determine the value of spinal cord lesions as a predictive factor for conversion in clinically isolated syndrome (CIS) patients. Patients with CIS and without immunomodulatory treatment were prospectively included. Age at onset, sex, clinical syndrome at onset, oligoclonal bands, and presence, number and location of lesions on brain and spinal MRI were analyzed. Conversion to multiple sclerosis (MS) was the primary endpoint. Cox regression was used to compare outcomes between groups. A total of 75 patients were included: 53 (71%) women, mean age at onset 32.7 years (SD ± 7.5), mean follow-up time 72.5 months (SD ± 9; range 17-104 months). There were 11 (14.6%) patients with one focal spinal cord lesion, while 13 (17%) patients had two or more spinal cord lesions at the first scan during the onset of the disease. Of the 23 patients (30.6%) who converted to clinically definite MS (CDMS), 2 had a normal spinal cord MRI, 8 patients had one spinal cord lesion, and 13 had more than one lesion on MRI (p < 0.001). In multivariable analyses, one focal spinal cord lesion was significantly associated with increased risk of conversion to MS (p = 0.01, HR 3.5, CI 95% 2.1-6.9), while the presence of two or more focal spinal cord lesions was independently associated with a higher risk of conversion to MS (p < 0.001, HR 5.9, CI 95% 3.2-10.8). CIS patients with an abnormal baseline spinal cord MRI have a higher risk for developing clinically definite MS, independent of brain lesions as well as the presence of cerebrospinal fluid oligoclonal banding (OSF-OB) .     

Anti-myelin antibodies predict the clinical outcome after a first episode suggestive of MS

The aim of this study was to test the contribution of anti-myelin antibodies in predicting conversion from clinically isolated syndrome (CIS) to multiple sclerosis (MS) when considering either Poser's or McDonald's diagnostic criteria. Fifty-one patients with CIS and abnormal brain MRI were imaged monthly for six months and then at 12, 18, 24, 36 months. At baseline serum samples testing antibodies against myelin oligodendrocyte glycoprotein (anti-MOG) and myelin basic protein (anti-MBP) were collected. During the 36-month follow-up, 26 (51%) patients developed a relapse thus becoming clinically definite MS (CDMS) according to Poser's criteria; 46 (90.2%) patients converted to MS according to McDonald's criteria. Out of 51 patients, 28 (54.9%) had either double or single positivity for anti-myelin antibodies. Antibody status significantly predicted MS according to Poser's criteria (P=0.004), but did not according to the McDonald's criteria. When compared to antibody negative patients, the risk of developing a relapse was 8.9 (95% CI: 2.7-29.8; P<0.001) for anti-MBP positive (anti-MBP+) patients and 1.5 (95% CI: 0.4-5.4; P=0.564) for those anti-MOG positive (anti-MOG+); double positive patients (ie, anti-MBP+/anti-MOG+) had a risk of relapse's occurrence equal to 3.4 (95% CI: 1.1-10.2; P=0.031). Also, the antibody status predicted the median time span from CIS to CDMS, that was of 36 months in the anti-MOG-/anti-MBP- group, 33 months in the anti-MOG+/anti-MBP- group, 24 months in the anti-MOG+/anti-MBP+ group and 12 months in the anti-MOG-/anti-MBP+ patients (P=0.003 by ANOVA). Our data support the prognostic value of anti-myelin antibodies in CIS patients at risk of CDMS, with positive patients showing shorter time interval to relapse occurrence than negative patients.     

The persistency of high levels of pSTAT3 expression in circulating CD4+ T cells from CIS patients favors the early conversion to clinically defined multiple sclerosis

Not all patients with clinically isolated syndrome (CIS) suggestive of multiple sclerosis (MS) develop clinically defined MS (CDMS). At first clinical event we observed increased production of IL17, IFNgamma and IL10 by peripheral blood mononuclear cells from patients with CIS that remained high in remission. In CD4+ T cells pSTAT3 expression was higher in patients who subsequently converted to CDMS than in patients who did not and controls. The persistency of high levels of pSTAT3 in circulating CD4+ T cells from CIS patients after the first clinical event may favor the early conversion to CDMS.     

CD4 T cell activation and disease activity at onset of multiple sclerosis

We studied CD4 T cell activation in patients with clinically isolated syndromes (CIS) suggesting an initial attack of multiple sclerosis. The percentage of blood CD26+ CD4 T cells was increased in these patients, and correlated with magnetic resonance imaging disease activity and clinical disease severity. In contrast, the percentage of CD25+ CD4 T cells in cerebrospinal fluid correlated negatively with the cerebrospinal fluid concentration of myelin basic protein and the presence of IgG oligoclonal bands. These results suggest that distinct systemic and intrathecal T cell activation states correlate with disease activity and risk of subsequently developing MS in CIS patients.     

CD8+ T cell activation correlates with disease activity in clinically isolated syndromes and is regulated by interferon-beta treatment

An increased percentage of blood CD8+ T cells from patients with clinically isolated syndromes (CIS) suggestive of multiple sclerosis (MS) was found to express CD26 and CD69. The percentage of CD26 or CD69 positive CD8+ T cells was higher in patients with MRI evidence of disease dissemination in space or with active MRI lesions than in the remaining patients. Treatment of MS with interferon (IFN)-beta resulted in a decrease in the percentage of CD26 and CD71 positive CD8+ T cells and an increase in the percentage of CD8+ T cells that expressed interleukin (IL)-10 and IL-13. CD8+ T cell activation in MS may be linked to disease activity already at disease onset, and is regulated by treatment with IFN-beta.     

Oligoclonal bands predict multiple sclerosis in children with optic neuritis

We retrospectively evaluated predictors of conversion to multiple sclerosis (MS) in 357 children with isolated optic neuritis (ON) as a first demyelinating event who had a median follow‐up of 4.0 years. Multiple Cox proportional‐hazards regressions revealed abnormal cranial magnet resonance imaging (cMRI; hazard ratio [HR] = 5.94, 95% confidence interval [CI] = 3.39–10.39, p < 0.001), presence of cerebrospinal fluid immunoglobulin G oligoclonal bands (OCB; HR = 3.69, 95% CI = 2.32–5.86, p < 0.001), and age (HR = 1.08 per year of age, 95% CI = 1.02–1.13, p = 0.003) as independent predictors of conversion, whereas sex and laterality (unilateral vs bilateral) had no influence. Combined cMRI and OCB positivity indicated a 26.84‐fold higher HR for developing MS compared to double negativity (95% CI = 12.26−58.74, p < 0.001). Accordingly, cerebrospinal fluid analysis may supplement cMRI to determine the risk of MS in children with isolated ON. Ann Neurol 2015;77:1076–1082     

Clinical predictors of early second event in patients with clinically isolated syndrome

This study aimed to determine the predictors of increased risk of a second demyelinating event within the first year of an initial demyelinating event (IDE) suggestive of early multiple sclerosis (MS). Patients with MS or clinically isolated syndrome (CIS) seen at the UCSF MS Center within one year of the IDE were studied. Univariate and multivariate Cox models were used to analyze predictors of having a second event within 1 year of the IDE. Of 330 patients with MS/CIS, 111 had a second event within 1 year. Non-white race/ethnicity (HR = 2.39, 95% CI [1.58, 3.60], p < 0.0001) and younger age (HR for each 10-year decrease in age = 1.51, 95% CI [1.28, 1.80], p < 0.0001) were strongly associated with an increased risk of having a second event within one year of onset. Having a lower number of functional systems affected by the IDE was also associated with an increased risk of early second event (HR for every one less FS involved = 1.31, 95% CI [1.06, 1.61], p = 0.011). These results were similar after adjusting for treatment of the IDE with steroids and disease-modifying therapy. Non-white race/ethnicity, younger age, and a lower number of FS affected by the IDE are associated with a substantially increased hazard ratio for a second demyelinating event within 1 year. Since early relapse is predictive of worse long-term outcome, identifying and treating such patients after the IDE may be of benefit to them.     

A three-year, multi-parametric MRI study in patients at presentation with CIS

OBJECTIVES: To define the extent of overall brain damage in patients with clinically isolated syndromes (CIS) suggestive of multiple sclerosis (MS) and to identify non-conventional magnetic resonance (MR) metrics predictive of evolution to definite MS. METHODS: Brain conventional and magnetization transfer (MT) MRI scans were obtained from 208 CIS patients and 55 matched healthy controls, recruited in four centres. Patients were assessed clinically at the time of MRI acquisition and after a median period of 3.1 years from disease onset. The following measures were derived: T2, T1 and gadolinium (Gd)- enhancing lesion volumes (LV), normalized brain volume (NBV), MTR histogram-derived quantities of the normal-appearing white matter (NAWM) and grey matter (GM). RESULTS: During the follow-up, 43 % of the patients converted to definite MS. At baseline, a significant inter-centre heterogeneity was detected for T2 LV (p = 0.003), T1 LV (p = 0.006), NBV (p < 0.001) and MTR histogram-derived metrics (p < 0.001). Pooled average MTR values differed between CIS patients and controls for NAWM (p = 0.003) and GM (p = 0.01). Gdactivity and positivity of International Panel (IP) criteria for disease dissemination in space (DIS), but not NAWM and GM MTR and NBV, were associated with evolution to definite MS. The final multivariable model retained only MRI IP criteria for DIS (p = 0.05; HR = 1.66, 95 % CI = 1.00-2.77) as an independent predictor of evolution to definite MS. CONCLUSIONS: Although irreversible tissue injury is present from the earliest clinical stages of MS, macroscopic focal lesions but not "diffuse" brain damage measured by MTR are associated to an increased risk of subsequent development of definite MS in CIS patients.     

Apoptosis of T cells in peripheral blood and cerebrospinal fluid is associated with disease activity of multiple sclerosis

Apoptotic elimination of pathogenic T cells is considered to be one of regulatory mechanisms in multiple sclerosis (MS). To explore the potential relationship between Fas-mediated apoptosis and the disease course of MS, we examined apoptosis, defined by annexin V (AV) binding, and Fas (CD95) expression in CD4+ and in CD8+ T cells in MS patients by using five-color flow cytometry. The percentage of AV+CD4+CD3+ cells and CD95+AV+CD4+CD3+ cells in peripheral blood and cerebrospinal fluid (CSF) were significantly decreased in active MS patients compared with inactive MS patients. A significantly lower proportion of CD95+AV+CD8+CD3+ cells in CSF was observed in active MS patients compared with inactive MS patients, but not in peripheral blood. These results indicate that the resistance of T cells to Fas-mediated apoptosis is involved in exacerbation of MS and/or that Fas-mediated apoptosis of T cells is associated with remission of MS.     

MRI criteria for dissemination in space in patients with clinically isolated syndromes: a multicentre follow-up study

BACKGROUND: The McDonald International Panel accepted the Barkhof/Tintoré criteria for providing MRI evidence of dissemination in space to allow a diagnosis of multiple sclerosis in patients with clinically isolated syndromes (CIS). We applied these criteria in a large cohort of patients with CIS, representative of those seen in a general diagnostic setting, to assess their accuracy in predicting conversion to definite multiple sclerosis and to identify factors that affect this risk. METHODS: In a collaborative study of seven centres, baseline MRI and clinical follow-up data for 532 patients with CIS were studied, with the development of a second clinical event used as the main outcome. All scans were scored for lesion counts and spatial lesion distribution to assess the fulfilment--ie, at least three out of four--of the Barkhof/Tintoré criteria. We used survival analysis and 2x2 tables to assess the test characteristics of the criteria at baseline. FINDINGS: Overall conversion rate was 32.5% with a median survival time of 85.3 months. Fulfilment of the criteria at baseline showed, after a survival time of 2 years, a conversion rate of about 45% (95% CI 37-53) versus about 10% (6-16) in those with no asymptomatic lesions at baseline (p<0.0001). For patients with a follow-up of at least 2 years, the fulfilment of the MRI criteria showed an accuracy of 68% (sensitivity 49%, specificity 79%) for predicting conversion and an increase in risk of nearly four times for conversion compared with those not fulfilling the criteria (odds ratio 3.7, 95% CI 2.3-5.9; p<0.0001). Cox proportional hazards regression analysis accorded with this increased risk. No effects were recorded on the performance of the criteria by sex, presenting symptoms, or centre. Age at baseline did have a small but significant effect as predictor (hazard ratio 0.97, 0.95-0.99; p=0.002), but did not affect the prognostic value of the MRI criteria. INTERPRETATION: MRI abnormalities have important prognostic value. The cut-off, based on the Barkhof/Tintoré criteria, as incorporated in the McDonald diagnostic scheme yields acceptable specificity, but could have lower sensitivity than previously reported.     

Upregulation of CD40 ligand and enhanced monocyte-platelet aggregate formation are associated with worse clinical outcome after ischaemic stroke

The white blood cell count and mean platelet volume determined shortly after the symptom onset are known as independent predictors for clinical outcome after stroke. In the present study we sought to evaluate the prognostic value of platelet-derived inflammatory biomarkers measured prospectively after an ischaemic event. Using five-colour flow cytometry, the platelet surface expression of CD40L, CD62P and subpopulations of leukocyte-platelet aggregates were assessed in 93 stroke patients on the first (V(0)), 10th (V(1)) and 90th (V(2)) day after stroke, and once in 65 disease controls. The clinical outcome was evaluated using the Scandinavian Stroke Scale (SSS) and modified Rankin Scale (mRS) at the same time points as blood sampling and 24 months after the event. Patients with either CD40L surface expression or the percentage of monocyte-platelet aggregates (M-plt) in the third tertile (T3) at V0 had a significantly lower score on the SSS at V(1). Patients with the percentage M-plt at V(0) higher than the median value of M-plt in controls were at increased risk of SSS < 40 at V(1) (odds ratio: 2.6; 95% confidence interval [CI]: 1.4 - 8.7; p=0.006). Patients with the percentage of M-plt in T3 at V(0) showed progressive decline in survival (hazard ratio [HR]: 1.6; 95% CI: 1.1-1.9; p=0.02) and a significantly higher number of recurrent vascular events (HR: 2.64; 95% CI: 1.3-3.2; p=0.02) when compared to the first tertile. In conclusion, increased levels of M-plt could be a predictive marker for both early outcome and long-term prognosis while increased CD40L was correlated with worse clinical outcome.     

Early differential diagnosis of multiple sclerosis using a new oligoclonal band test

BACKGROUND: Intrathecal IgG synthesis (ITGS), in conjunction with magnetic resonance imaging, can help in the early diagnosis of multiple sclerosis (MS). Recently, we developed a new oligoclonal IgG band (OCGB) test for ITGS detection that is more sensitive and easier to interpret than previously described methods. OBJECTIVE: To assess the accuracy of a new OCGB detection test in the diagnosis of MS. DESIGN: Prospective observational study. SETTING: A hospital neurology department.Patients A total of 385 patients with various neurologic disorders. MAIN OUTCOME MEASURES: The sensitivity and specificity of the OCGB detection test for MS diagnosis. RESULTS: Intrathecal IgG synthesis was found in 127 patients with MS (96.2%), 18 (35.3%) with central nervous system infections, and 1 with motor neuron disease. Two patterns reflected ITGS. One pattern, showing OCGBs restricted to cerebrospinal fluid, was predominantly found in MS. The other pattern, with OCGBs in serum and additional bands in cerebrospinal fluid, was mostly found in central nervous system infections. No patients with other inflammatory neurologic diseases showed ITGS. These patients frequently displayed a mirror pattern, with identical bands in serum and cerebrospinal fluid. Considering all patients, the sensitivity for the diagnosis of MS was 96.2%, and the specificity was 92.5%. Excluding infections, which usually do not present a differential diagnosis problem with MS, the sensitivity was still 96.2%, and the specificity increased to 99.5%. CONCLUSION: The accuracy of this OCGB method reinforces the value of cerebrospinal fluid studies in the early differential diagnosis of MS.     

Increased T cell expression of CD154 (CD40-ligand) in multiple sclerosis

CD154 (CD40-ligand, gp39), expressed on activated T cells, is crucial in T cell-dependent immune responses and may be involved in the pathogenesis of multiple sclerosis (MS). We studied cerebro-spinal fluid and peripheral blood T cell expression of CD154 in MS by flow cytometry. Patients with secondary progressive MS (SPMS) had constitutive CD154 expression on CD4 and CD8 T cells in blood. Constitutive CD154 expression was not observed in patients with relapsing-remitting MS (RRMS) or clinically isolated syndromes (CIS) suggestive of demyelinating disease. After ex vivo activation CD154 was, however, expressed on a higher percentage of T cells from patients with CIS or RRMS than from healthy control subjects. These results suggest involvement of CD154 in the pathogenesis of MS, and the shift from a relapsing-remitting to a secondary progressive disease course may be associated with constitutive, systemic CD154 expression.     

Mortality of patients with multiple sclerosis: a cohort study in UK primary care

We aimed to estimate rates, causes and risk factors of all-cause mortality in a large population-based cohort of multiple sclerosis (MS) patients compared with patients without MS. Using data from the UK General Practice Research Database, we identified MS cases diagnosed during 2001–2006 and validated using patients’ original records where possible. We also included MS cases during 1993–2000 identified and validated in an earlier study. Cases were matched to up to ten referents without MS by age, sex, index date (date of first MS diagnosis for cases and equivalent reference date for controls), general practice and length of medical history before first MS diagnosis. Patients were followed up to identify deaths; hazard ratios (HRs) and 95 % confidence intervals (CIs) were estimated using Cox-proportional regression. MS patients (N = 1,822) had a significantly increased risk of all-cause mortality compared with referents (N = 18,211); adjusted HR 1.7 (95 % CI 1.4–2.1). Compared with referents, female MS patients had a higher but not significantly different HR for death than males; adjusted HR 1.86 (95 % CI 1.46–2.38) vs. HR 1.31 (95 % CI 0.93–1.84), respectively. The most commonly recorded cause of death in MS patients was ‘MS’ (41 %), with a higher proportion recorded among younger patients. A significantly higher proportion of referents than MS patients had cancer recorded as cause of death (40 vs. 19 %). Patients with MS have a significant 1.7-fold increased risk of all-cause mortality compared with the general population. MS is the most commonly recorded cause of death among MS patients.     

Enumeration of T, B and natural killer peripheral blood cells of patients with multiple sclerosis and controls.

The median percentages of peripheral blood immunoglobulin-positive (Ig+) lymphocytes (8%, n = 46), CD8+ (12%, n = 49) and CD57+ cell numbers (5%, n = 37) of patients suffering from multiple sclerosis (MS) were significantly (p less than 0.05) lower than the values of age- and sex-matched healthy individuals (Ig+ cells: 13%, n = 46; CD8+ cells: 17%, n = 49; CD57+ cells: 9%, n = 37). Comparison of calculations on decreased peripheral blood cell counts and increased brain cell counts in MS patients revealed that sequestration of blood cells into the MS brain is a possible explanation of these findings.     

Oligoclonal bands and MRI in clinically isolated syndromes: predicting conversion time to multiple sclerosis

The objective of the study was to evaluate whether the presence of oligoclonal bands (OB) adds information in predicting CIS conversion to clinical definite multiple sclerosis (CDMS) and conversion time to CDMS. From 1998 to 2006, CIS patients were included in a prospective study. Patients underwent brain MRI and OB determination within 2 months of the first demyelinating event. We analyzed conversion to CDMS and time to conversion to CDMS according to abnormal MRI and the presence of OB. Forty patients were included. Fifteen patients (37%) converted to CDMS; 14 of them (93.3%) had abnormal baseline MRI (P = 0.01, RR = 5.9; 95% CI 1.3–10.1) and 13 (86.7%) had positive OB in CSF (P = <0.01, RR = 5.3; 95% CI 1.6–9.5). The risk of conversion to CDMS in patients with positive OB and abnormal baseline MRI was significantly higher compared to patients negative for both tests or with only one positive (RR = 9.1; 95% CI 3.5–14.6). Time to conversion to CDMS was 6.8 ± 3.5 months for patients with OB and abnormal baseline MRI and 19 ± 14 months for patients with only one abnormal test. CIS patients with abnormal baseline OB in CSF have a higher risk for developing CDMS. Regarding conversion time to CDMS, when abnormal MRI was added to positive OB, patients converted faster (mean time, 6 vs. 19 months). This information may be useful when considering treatment in CIS patients.     

CD45RA+ ICAM-3+ lymphocytes in cerebrospinal fluid and blood as markers of disease activity in patients with multiple sclerosis

OBJECTIVES: Autoreactive T cells targeted against antigens of the myelin sheath are suggested to play an important role in the pathogenesis of multiple sclerosis (MS). Naive (CD45RA+) T cells and intercellular adhesion molecule-3 (ICAM-3) are markers for un-activated lymphocytes. This study was performed to investigate, whether the expression levels of these antigens both on cerebrospinal fluid (CSF) and peripheral blood lymphocytes can be used as activity markers in MS. MATERIALS AND METHODS: Corresponding blood and CSF samples were obtained from 31 patients with relapsing-remitting MS. Of the 31 MS patients 23 were suffering from acute relapses at the time of examination and all of them were treated with high-dose methylprednisolone (MP). Blood was collected again on the 10th day of therapy and after 3 months. The control group consisted of 12 healthy persons. Two-color flow cytometry was performed to evaluate the percentage of both CD45RA+ and ICAM-3+ cells within the lymphocyte population. RESULTS: The percentage of CD45RA+ ICAM-3+ cells in the CSF of MS patients with relapses was significantly increased compared to patients in remission (P<0.05). In blood, a significantly lower percentage of CD45RA+ ICAM-3+ lymphocytes was found in both patient groups compared to healthy controls (Relapse: P<0.05, Remission: P<0.10). Additionally, we found a significant increase (P < 0.01) in the percentage of CD45RA+ ICAM-3+ lymphocytes in blood of MS patients suffering from acute relapse on the 10th day of high-dose MP treatment. CONCLUSION: Our data suggest that the percentage of CD45RA+ ICAM-3+ lymphocytes in CSF can be used as marker of disease activity in MS patients.     

Does vitamin D deficiency predict early conversion of clinically isolated syndrome? A preliminary Egyptian study

Background: It has been suggested that vitamin D influences the immunoregulation and subsequently affects the risk for conversion of clinically isolated syndrome (CIS) to clinically definite multiple sclerosis (MS). There is little information regarding the relationship between levels of vitamin D and CIS conversion to MS in Egyptian patients.

Objective: It is to study contribution of vitamin D deficiency to conversion of CIS to clinically definite multiple sclerosis (CDMS) and correlation of vitamin D level to cognitive and magnetic resonance imaging (MRI) results.

Patients and methods: A longitudinal prospective case control study was conducted on 43 Egyptian patients diagnosed as CIS according to McDonald criteria (2010). Clinical presentation, brain MRI and 25-hydroxyvitamin D levels were evaluated at baseline and after one-year follow-up.

Results: The CIS patients that converted to MS showed significant lower vitamin D level (p < 0.001) than the non-convertors. Multivariate logistic regression analysis revealed that the CIS patients with lower 25-hydroxyvitamin D level (p < 0.001) are at higher risk for early conversion to MS. There was a significant positive correlation between the vitamin D level and PASAT (r = 0.36, p = 0.02). It was found that there was a significant negative correlation between vitamin D level and MRI T₂ load (r = ?0.38, p = 0.01).

Conclusion: The low level of 25-hydroxyvitamin D may predict early conversion to clinically definite MS. Early vitamin D supplementation is recommended in patients with CIS.     

Causes of death in patients with multiple sclerosis and matched referent subjects: a population‐based cohort study

Background and purpose: Multiple sclerosis (MS) has been associated with increased mortality rates. However, influence of lifestyle parameters remains unknown, and inconsistencies exist regarding findings for causes of death. Methods: We conducted a population‐based cohort study using the General Practice Research Database, Hospital Episode Statistics, and national death certificates (January 2001 through March 2008). To each patient with MS (n = 1270), up to six referent subjects without MS were matched by age, gender, and practice. Cox proportional hazards models were used to estimate mortality rate ratios (HRs). Results: Patients with MS had a 3.5‐fold increased mortality rate for all‐cause mortality, compared with referent subjects (HR 3.51, 95% CI 2.63–4.69). The rate further increased amongst current smokers (HR 6.72, 95% CI 4.16–10.87) (but not in ex‐smokers) and subjects with a body mass index of <20 kg/m² (HR 6.67, 95% CI 3.50–12.73). The HR was highest for infectious/respiratory‐related deaths (HR 7.69, 95% CI 4.92–12.02) and was significantly increased for deaths related to cardiovascular diseases (2.4‐fold) and cancer (1.9‐fold), but not for accidents and suicide related deaths. Conclusion: British patients with MS have a 3.5‐fold increased mortality rate compared with the general population. Smoking and respiratory diseases are major (potentially preventable) factors related to increased mortality rate amongst patients with MS.