Biomedical subjects

N Téllez

Publications and source records attributed to N Téllez.

8 recordsLinked to original sources

PubMed2007

Adenoviral overproduction of interleukin-1 receptor antagonist increases beta cell replication and mass in syngeneically transplanted islets, and improves metabolic outcome.

AIMS/HYPOTHESIS: Interleukin-1 receptor antagonist (IL1RN, also known as IL1RA) is a naturally occurring inhibitor of IL-1 action and its overproduction protects pancreatic islets from the deleterious effects of IL-1beta on beta cell replication, apoptosis and function. The aim of this study was to determine whether viral gene transfer of the Il1rn gene into rat islets ex vivo had a beneficial effect on the outcome of the graft. MATERIALS AND METHODS: Streptozotocin-diabetic Lewis rats were syngeneically transplanted with 500 or 800 Ad-Il1rn-infected or uninfected islets. Islet grafts were collected on day 3, 10 or 28 after transplantation and beta cell apoptosis, replication, size and mass were determined. RESULTS: Animals transplanted with 500 islets remained hyperglycaemic throughout the follow-up, as expected. Beta cell replication increased in the Ad-Il1rn group on days 3, 10 and 28 after transplantation compared with normal pancreas. In uninfected islets, by contrast, beta cell replication was increased only on day 10. Beta cell apoptosis was increased in all transplanted groups; it was 25% lower in the Ad-Il1rn than in uninfected groups, but differences were not statistically significant. The initially transplanted beta cell mass was reduced on day 3, increasing subsequently in Ad-Il1rn grafts, but not in uninfected grafts. When 800 islets were transplanted, all animals grafted with Ad-Il1rn-infected islets, but only 40% of those transplanted with uninfected islets, achieved normoglycaemia 14 days after transplantation. CONCLUSIONS/INTERPRETATION: Overproduction of IL1RN increased beta cell replication and mass of islet grafts and reduced the beta cell number required to achieve normoglycaemia.

Adenoviridae↗

PubMed2006

Baseline MRI predicts future attacks and disability in clinically isolated syndromes.

OBJECTIVE: To determine the relation between baseline MRI and both conversion to multiple sclerosis (MS) and development of disability in a cohort of patients with clinically isolated syndromes (CIS). METHODS: From 1995 to 1998, 175 consecutive patients with CIS underwent brain MRI within 3 months of their first attack and again 12 months and 5 years later. We studied the number and location of lesions at baseline and development of new T2 lesions. We also analyzed conversion to MS and development of disability (Expanded Disability Status Scale [EDSS] > or = 3.0). RESULTS: We included 156 patients with CIS followed for a median of 7 years. Compared to the reference group with 0 Barkhof criteria at baseline MRI, patients with one or two Barkhof criteria showed an adjusted hazard ratio (HR) of 6.1 (2.2 to 16.6) and patients with three to four Barkhof criteria of 17.0 (6.7 to 43) for conversion to MS and differentiated patients with low, medium, and high conversion risk. EDSS at year 5 correlated with baseline number of Barkhof criteria (r = 0.46, p < 0.0001). When categorizing by number of baseline lesions, similar results were seen. Patients with a baseline MRI with three to four Barkhof criteria had an adjusted HR of 3.9 (1.1 to 13.6) for reaching EDSS > or = 3.0. Only 10% of the latter had disability at year 5, but 40% reached this at 8 years. CONCLUSIONS: Baseline MRI determines the risk for converting to clinically definite multiple sclerosis and correlates with disability at 5 years. The proportion of patients developing disability is low during the first 5 years but rapidly increases shortly after.

Adult↗

PubMed2006

Fatigue in multiple sclerosis persists over time: a longitudinal study.

BACKGROUND AND OBJECTIVE: Fatigue is one of the most frequent symptoms in multiple sclerosis (MS) but there is a lack of knowledge about its behaviour over time. The aim of our study was to investigate changes in fatigue in a large cohort of MS patients and to determine the relationship between changes in disability and depression with changes in fatigue severity. METHODS: We studied fatigue in 227 MS consecutive patients and again after one year. During the clinical interview, we recorded the patient's degree of disability using the Expanded Disability Status Scale and relapses; fatigue was measured by means of the Modified Fatigue Impact Scale (MFIS) and Fatigue Severity Scale (FSS) and depression was measured by the Beck Depression Inventory (BDI). RESULTS: After a mean follow-up of 18 months, 86.8% of patients who were fatigued at study onset remained in a fatigued status, whereas 25% of those without fatigue at onset had become fatigued at the end of follow-up. We observed that only variations on BDI scores positively correlate with variations on fatigue scales, mainly with MFIS (r = 0.49, p < 0.0001). An increase of BDI score was the factor that best predicted the increase of fatigue over time. No differences in the increase of fatigue were found between patients with and without progression of disability during the follow-up period, or between patients with or without relapses. CONCLUSIONS: Fatigue in MS persists over time. Changes in mood status but not in disability are related to changes in fatigue in MS patients.

Adult↗

PubMed2006

Neuromyelitis optica diagnosis in clinically isolated syndromes suggestive of multiple sclerosis.

The authors assessed the extent of overlap between current diagnostic criteria of neuromyelitis optica (NMO) and multiple sclerosis (MS) by applying NMO criteria to a large cohort of 320 patients with clinically isolated syndromes (CIS). Twenty-three (7.2%) patients fulfilled NMO absolute criteria at some time and 1 (0.3%) also fulfilled one major supportive criterion. Therefore, even by systematically applying NMO criteria in patients with CIS, NMO diagnosis is reached infrequently.

Adult↗

PubMed2005

Long-term clinical outcome of primary progressive MS: predictive value of clinical and MRI data.

The authors sought to identify clinical and MRI predictors of outcome in primary progressive multiple sclerosis (PPMS). Clinical and MRI assessments were performed at baseline and 2 and 5 years (clinical only). At baseline, disease duration, expanded disability status scale (EDSS) and brain volume predicted outcome. Adding short-term change variables, baseline EDSS, changes in T2* lesion load and cord area, and number of new lesions were predictive. Clinical and MRI variables predict long-term outcome in PPMS.

Atrophy↗

PubMed2005

Adenoviral overexpression of interleukin-1 receptor antagonist protein increases beta-cell replication in rat pancreatic islets.

The naturally occurring inhibitor of interleukin-1 (IL-1) action, interleukin-1 receptor antagonist protein (IRAP), binds to the type 1 IL-1 receptor but does not initiate IL-1 signal transduction. In this study, we have determined the effects of IL-1beta and IRAP overexpression on adult beta-cell replication and viability. IL-1beta reduced dramatically beta-cell replication in adult rat islets both at 5.5 mM (control: 0.29+/-0.04%; IL-1beta: 0.02+/-0.02%, P<0.05) and 22.2 mM glucose (control: 0.84+/-0.2%; IL-1beta: 0.05+/-0.05%, P<0.05). This effect was completely prevented in islets overexpressing IRAP after adenoviral gene transfer at 5.5 mM (Ad-IL-1Ra+IL-1beta: 0.84+/-0.1%, P<0.05) and 22.2 mM glucose (Ad-IL-1Ra+IL-1beta: 1.22+/-0.2%, P<0.05). Moreover, overexpression of IRAP increased glucose-stimulated beta-cell replication in the absence of IL-1beta exposure (Ad-IL-1Ra: 1.59+/-0.5%, P<0.05). beta-Cell death (TUNEL technique) was increased in IL-1beta-exposed islets but not in Ad-IL-1Ra-infected islets (control: 0.82+/-0.2%; control+IL-1beta: 1.77+/-0.2; IRAP: 0.61+/-0.2%; IRAP+IL-1beta: 0.86+/-0.1%, P<0.05). Comparable results were obtained by flow cytometry. To determine the effect of IRAP overexpression on beta-cell replication in vivo, Ad-IL-1Ra-transduced islets were transplanted into streptozotocin diabetic rats. beta-Cell replication was significantly increased in IRAP-overexpressing islet grafts (0.98+/-0.3%, P<0.05) compared to normal pancreas (0.35+/-0.02%), but not in control islet grafts (0.50+/-0.1%). This study shows that in addition to the effects of IL-1beta on beta-cell viability, this cytokine exerts a deleterious action on beta-cell replication, which can be prevented by IRAP overexpression, and provides support for the potential use of IRAP as a therapeutic tool.

Adenoviridae↗

PubMed2005

Does the Modified Fatigue Impact Scale offer a more comprehensive assessment of fatigue in MS?

BACKGROUND: As a symptom of multiple sclerosis (MS), fatigue is difficult to manage because of its unknown etiology, the lack of efficacy of the drugs tested to date and the absence of consensus about which would be the ideal measure to assess fatigue. OBJECTIVE: Our aim was to assess the frequency of fatigue in a sample of MS patients and healthy controls (HC) using two fatigue scales, the Fatigue Severity Scale (FSS) and the Modified Fatigue Impact Scale (MFIS) with physical, cognitive and psychosocial subscales. We also studied the relationship fatigue has with depression, disability and interferon beta. METHODS: Three hundred and fifty-four individuals (231 MS patients and 123 HC) were included in this cross-sectional study. Fatigue was assessed using the FSS and MFIS. Depression was measured by the Beck Depression Inventory (BDI), and disability by the Expanded Disability Status Scale (EDSS). A status of fatigue was considered when the FSS > or =5, of non-fatigue when the FSS < or =4, and scores between 4.1 and 4.9 were considered doubtful fatigue cases. RESULTS: Fifty-five percent of MS patients and 13% of HC were fatigued. The global MFIS score positively correlated with the FSS in MS and HC (r =0.68 for MS and r =0.59 for HC, p <0.0001). Nonetheless, the MFIS physical subscale showed the strongest correlation score with the FSS (r =0.75, p <0.0001). In addition, a prediction analysis showed the physical MFIS subscale to be the only independent predictor of FSS score (p <0.0001), suggesting other aspects of fatigue, as cognition and psychosocial functions, may be explored by the FSS to a lesser extent. Depression also correlated with fatigue (r =0.48 for the FSS and r =0.7 for the MFIS, p <0.0001) and, although EDSS correlated with fatigue as well, the scores decreased after correcting for depression. Interferon beta showed no relationship with fatigue. CONCLUSIONS: Fatigue is a frequent symptom found in MS patients and clearly related with depression. Each fatigue scale correlates with one another, indicating that they are measuring similar constructs. Nevertheless, spheres of fatigue as cognition and psychosocial functions are probably better measured by the MFIS, although this hypothesis will need to be confirmed with appropriate psychometrical testing.

Adult↗

PubMed2004

[Modafinil and fatigue in multiple sclerosis].

Fatigue is one of the most frequent and disabling symptoms in multiple sclerosis (MS) patients. This symptom's etiopathogenic mechanism, though not known, seems complex and multifactorial, and its therapeutic management is difficult. Different treatments have been tested in recent years, but a weak efficacy that may be limited in time has been observed. Recently, modafinil has been suggested as a possible treatment for fatigue in MS patients, although nowadays, the only use of modafinil approved by the Food and Drug Administration is narcolepsy. Modafinil, 2-([difenilmetil]sulfinil), acetamide is a state of wakeness promoter, and although its exact action mechanism is not known, it differs from other central nervous system stimulants because no dopaminergic activation is observed, and its action take place at the hypothalamic level. It is known that modafinil increases the proportion of high-frequency alpha waves and reduces delta and theta waves, increasing vigilance. Although few studies exist on modafinil in MS patients with fatigue, the results suggest this drug as a promising treatment, because of its efficacy and safety, and should encourage us to continue working in this area.

Benzhydryl Compounds↗