Biomedical subjects

Dimitrios Vassilopoulos

Publications and source records attributed to Dimitrios Vassilopoulos.

At least 19 recordsLinked to original sources

PubMed2007

Cochlear function in facioscapulohumeral muscular dystrophy.

OBJECTIVE: Facioscapulohumeral muscular dystrophy (FSHD) is commonly associated with high-frequency hearing impairment. Our objective was to evaluate a group of normally hearing patients with FSHD using otoacoustic emissions. STUDY DESIGN: Prospective, randomized clinical trial. SETTING: A tertiary University-based referral center in Athens, Greece. PATIENTS: The study group consisted of a consecutive sample of 24 patients diagnosed on clinical, histopathologic, and genetic grounds as having FSHD. All subjects were selected on the basis of normal to near normal audiometric pure tone thresholds. Controls consisted of 40 age-matched healthy volunteers. INTERVENTIONS: Transiently evoked otoacoustic emissions were performed. Whole reproducibility and total response were measured, as well as partial scores at the octave bands centered at 1, 2, 3, 4, and 5 kHz. MAIN OUTCOME MEASURES: Transiently evoked otoacoustic emission measurements were compared between the two groups. RESULTS: The audiometric findings were normal to near normal for both groups. Compared with controls, most patients had diminished scores in both whole and partial reproducibility scores and overall and partial response scores. CONCLUSION: Despite normal hearing, subclinical involvement of the cochlea is quite common in patients with FSHD. Our findings support the genetic homogeneity of this disorder and its association with cochlear damage. Otoacoustic emissions might provide a useful tool in the clinical workup and follow-up of these patients.

Acoustic Stimulation↗

PubMed2006

Changes in LORETA and conventional patterns of P600 after steroid treatment in multiple sclerosis patients.

OBJECTIVE: The P600 component of event-related potentials (ERPs) reflecting the 'rule-governed sequence of information processing', has been associated with multiple sclerosis (MS)-related cognition. The present study aimed at examining the effects of methylprednisolone treatment in MS patients on cognition as reflected by the low-resolution brain electromagnetic tomography (LORETA) of the P600 as well as its conventional constituents (amplitudes and latencies) recorded during a working memory (WM) test. METHOD: A paired LORETA comparison was performed in the P600 component of ERPs elicited during a (WM) test in 18 MS patients suffering from the relapsing-remitting form, before and after 1 week treatment with methylprednisolone. The P600 component was also evaluated in 16 healthy controls matched to the patients on age and educational level. RESULTS: When pre- and post-treatment recordings of LORETA were compared all patients as a group showed significantly different patterns of current density activation located at right frontal lobe. The treatment was accompanied by an increase of the amplitude of P600 at the right frontoparietal area. In the post-treatment phase the patients exhibited significant improvement of the memory performance as compared to themselves before treatment. As a result both the P600 amplitudes and memory performance at post-treatment were closer to those exhibited by normal controls. CONCLUSION: These findings support the notion that steroid treatment in relapsing-remitting MS patients, may exert a beneficial effect in 'rule-governed sequence of information processing'.

Acoustic Stimulation↗

PubMed2006

Morphological and morphometrical study of human muscle spindles in Werdnig-Hoffmann disease (infantile spinal muscular atrophy type I).

A study was made of the morphological and morphometrical features of muscle spindles in biopsies of patients with Werdnig-Hoffmann disease (infantile spinal muscular atrophy type I) to investigate the possible involvement of the muscle spindles in the pathological processes of the disease. A total of 57 muscle spindles from 26 cases were studied. The parameters determined were: the diameter and area of spindles, the number, diameter and area of intrafusal fibers, the number and area of nuclei. In addition, the ratio of the area of the intrafusal fibers to the area of nuclei and the ratio of the area of the spindle to the area of the intrafusal fibers were calculated. Statistical evaluation of the data showed significant differences regarding the area of the muscle spindle, the diameter of the intrafusal fibers and the mean area of nuclei of the intrafusal fibers, which were all smaller in patients than in controls (p=0.03, 0.01 and 0.02, respectively), while the thickness of the capsule was greater in patients than in controls (p=0.01). Our results indicate that the muscle spindle participates in the pathological processes of Werdnig-Hoffmann disease.

Adult↗

PubMed2006

Reply to "The role of soluble interleukin-6 receptor in inflammatory diseases" [Immunol Lett 2005;98(1):171].

We agree with the comments of Mr. Maggio and colleagues. The exact role of serum IL-6R and the relation between this and the IL-6/sIL-6R complex in inflammatory disorders has not been completely clarified. We suggest a discrepancy between sIL-6R concentrations and measurable IL-6/sIL-6R complex, not excluding the positive contribution of sIL-6R as a marker of neuro-immunoregulatory and inflammatory status in the central nervous system.

Humans↗

PubMed2006

Myelodysplastic syndrome presenting as acquired ichthyosis.

Ichthyosis is a cutaneous keratinization disorder that can either be congenital or acquired. Acquired ichthyosis has been reported in association with a variety of neoplastic, autoimmune, and infectious diseases. We report the case of a 68-year-old woman who presented with generalized ichthyosis as the first manifestation of myelodysplastic syndrome. This is the first fully described case of such an association in the English literature.

Journal Article↗

PubMed2006

Dialogue between the brain and the immune system in inflammatory arthritis.

The crosstalk between the brain and the immune system in inflammatory arthritis is exerted mainly through the activation or downregulation of the hypothalamic-pituitary-adrenal (HPA), the hypothalamic-pituitary-gonadal (HPG), and the hypothalamic-autonomic nervous system (HANS) axes. In this review, we will present an overview of the most recent data regarding the regulation of these complex pathways of neuroendocrine response during the different phases of inflammatory arthritides such as rheumatoid arthritis (RA). Furthermore, the effect of the most recently available biologic therapies like anti-tumor necrosis factor (TNF-a) on the neuroendocrine function in patients with RA will be reviewed.

Animals↗

PubMed2005

Hashimoto encephalopathy with pegylated interferon alfa-2b and ribavirin.

OBJECTIVE: To report an instance of Hashimoto encephalopathy probably resulting from pegylated interferon alfa-2b and ribavirin. CASE SUMMARY: A 36-year-old woman with a 10-year history of autoimmune thyroiditis presented with symptoms and signs consistent with Hashimoto encephalopathy during therapy with pegylated interferon alfa-2b and ribavirin for chronic hepatitis C. DISCUSSION: Hashimoto encephalopathy is a rare autoimmune condition that occurs in patients with Hashimoto thyroiditis and high titers of antithyroid antibodies. It is characterized by a variety of nonspecific neuropsychiatric symptoms, increased cerebrospinal fluid protein level, and abnormal brain imaging and electroencephalogram. Prompt response to corticosteroids is observed in most cases. As of August 29, 2005, this is the first report of such an association. An objective causality assessment revealed that the Hashimoto encephalopathy was probably caused by the patient's medications. CONCLUSIONS: Hashimoto encephalopathy may rarely be triggered by interferon alfa therapy in susceptible patients.

Adult↗

PubMed2005

Plasma testosterone in male patients with Huntington's disease: relations to severity of illness and dementia.

Huntington's disease (HD) is a neurodegenerative disorder characterized by motor, cognitive, and psychiatric symptoms and by a progressive loss among other, of dopaminergic receptors in striatum, cortex, and hypothalamus. Central dopaminergic activity has been implicated in the regulation of sex hormones. Several features of testosterone deficiency, such as reduced muscle mass, depressive mood, and cognitive impairment, are often present in HD patients, but data on their testosterone levels are lacking. We assessed plasma levels of testosterone, LH, and FSH in 42 male patients with HD, confirmed by molecular genetic analysis, and searched for differences from age-matched healthy male subjects and for relations to CAG repeat number, age, age range, 26 to 76 (mean, 50.7 +/- 12.3) years; duration of illness range, 1 to 23 (mean, 6.7 +/- 6.3) years; and CAG repeat numbers from 40 to 65 (45.1 +/- 3.8). Disease symptomatology was assessed using the Unified Huntington's Disease Rating Scale. Testosterone and LH levels of the patients were significantly lower compared to the levels of 44 age-matched (mean age, 48.9 +/- 13.0, range, 26-76 years) healthy men. Severity of illness was negatively related to plasma testosterone levels. Further, low testosterone levels were associated with dementia but not with depression or psychotic features. Clinical studies with selected HD patients are needed to evaluate possible beneficial effects of androgen substitution therapy on cognitive functions, depression, muscle mass and strength, general well-being, and, eventually, neuroprotective effects.

Adult↗

PubMed2005

Reduced expression of metabotropic glutamate receptor 2mRNA in T cells of ALS patients.

Metabotropic glutamate receptors alter the vulnerability of neurons to excitotoxic damage and are reported to display abnormal expression in the central nervous system of ALS patients. Using reverse transcriptase polymerase chain reaction, we investigated the mRNA expression of specific metabotropic glutamate receptor subtypes in T lymphocytes of 20 patients with sporadic ALS, compared with healthy age-matched control subjects and patients with other neurological disorders. The levels of metabotropic glutamate receptor 2 mRNA were markedly reduced, whereas the expression of other subtypes (1b, 3, 8) was similar to control levels. Our findings may provide a reliable peripheral marker of the glutamatergic dysfunction that characterizes ALS.

Adult↗

PubMed2005

Real-time PCR analysis of trinucleotide repeat allele expansions in the androgen receptor gene.

INTRODUCTION: The expansion of specific trinucleotide repeats results in certain genetic disorders. METHOD: Real-time PCR analysis was used to rapidly discriminate between normal and expanded (CAG)(n) alleles in the androgen receptor gene. RESULT: The difference in melting temperature (T(m)) between the most common normal and expanded alleles was approximately 1 degrees C. CONCLUSION: Real-time PCR analysis seems to be a highly reliable and rapid method, which may facilitate the first molecular approach to human trinucleotide repeat disorders.

Alleles↗

PubMed2005

Extrahepatic immunological complications of hepatitis C virus infection.

Chronic hepatitis C virus (HCV) infection is frequently associated with a number of extrahepatic complications. In the majority of cases the underlying pathogenetic mechanisms are immune mediated, as evidenced by the presence of circulating autoantibodies (mixed cryoglobulinemia), whereas for others a localized host cellular immune response is implicated (e.g. sialadenitis, lichen planus). In this review, the latest data on the pathogenesis and clinical manifestations of the most common autoimmune extrahepatic manifestations of chronic HCV infection are presented.

Autoantibodies↗

PubMed2005

Angioimmunoblastic T-cell lymphoma-associated arthritis: case report and literature review.

Angioimmunoblastic T-cell lymphoma (AITL) is a rare type of non-Hodgkin lymphoma with systemic manifestations, including fever, lymphadenopathy, rash, and rarely arthritis. We report the case of a patient who presented with symmetric inflammatory polyarthritis and skin nodules resembling rheumatoid arthritis (RA). The patient responded initially to low-dose prednisolone, but 12 months later, he developed typical features of AITL. The characteristics of AITL-associated arthritis from 16 additional cases from the English literature are also reviewed. AITL-associated arthritis is an uncommon manifestation of angioimmunoblastic lymphoma that can mimic RA, especially when the typical systemic features of lymphoma are absent. This type of arthritis should be included in the differential diagnosis of patients presenting with an inflammatory polyarthritis.

Arthritis↗

PubMed2005

Modulation of voltage-gated potassium channels in human T lymphocytes by extracellular glutamate.

Glutamate is present in the plasma under tightly regulated concentrations. However, under conditions of immune deficiency, such as AIDS and malignancy, its plasma levels are highly elevated. In vitro, glutamate interacts with T lymphocytes, affecting mitogen-induced calcium responses, whereas at high doses, it impairs T lymphocyte proliferation, a process strongly dependent on the activity of voltage-gated potassium channels. In this study, we demonstrate novel dose-related effects of the endogenous ligand glutamate and its metabotropic and non-N-methyl-D-aspartic acid receptor agonists on the electrophysiological properties of native Kv1.3 channels of human T lymphocytes. Glutamate, at concentrations within normal plasma levels, positively modulates Kv1.3 channel gating, causing currents to activate faster and at significantly more hyperpolarized potentials, hence rendering the T lymphocyte readily responsive to immune stimuli. This effect is maximal at 1 microM Glu and is fully mimicked by a 100 microM concentration of the metabotropic receptor agonist trans-(1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid. Most importantly, Glu, at concentrations > or =100 microM, which in vitro produce suppression of mitogen-induced proliferation, significantly decreases whole-cell potassium currents by increasing current and steady-state inactivation. This effect saturates at 1000 microM and seems to result from the subsequent activation of low-affinity metabotropic Glu receptors, as suggested by specific agonist data. Therefore, the antiproliferative effects of high glutamate may, at least in part, result from its inhibitory effect on the potassium current, suggesting an in vivo immunosuppressive role of elevated plasma glutamate.

Cells, Cultured↗

PubMed2005

Morphometric study of the human muscle spindle.

OBJECTIVE: To study the morphometric characteristics of the human muscle spindle in normal muscle and to investigate the influence of aging. STUDY DESIGN: The following variables were studied in 72 spindles: area and diameter of the spindle; thickness of the capsule; number, area and diameter of fibers; and number and area of nuclei. RESULTS: In deltoid and extensor digitorum brevis muscles, a reduction in the diameter of the spindle as a function of age was found, while no statistically significant change in the variables as a function of age was observed in the quadriceps femoris and biceps muscles. In the deltoid, a reduction in the number of fibers and an increase in their diameter were also observed. CONCLUSION: These findings could prove useful in the study of the spindle in relation to disease.

Adult↗

PubMed2005

Nonsystemic vasculitic neuropathy: a clinicopathological study of 22 cases.

OBJECTIVE: The involvement of the peripheral nervous system in patients with systemic vasculitis has been reported, but nonsystemic peripheral nervous system vasculitis is not so well known. We investigated the clinical, electrophysiological, and pathological features of nonsystemic vasculitic neuropathy (NSVN) in order to establish the clinical and histological manifestations and to promote the earlier diagnosis of the syndrome. METHODS: Biopsies were selected from over 700 sural nerve biopsies performed at the Section of Neuropathology, Neurological Clinic of Athens University Hospital. The diagnosis of vasculitis was based on established clinicopathological criteria. Other causes of peripheral neuropathy were excluded. Complete laboratory, clinical, electrophysiological, and pathological studies were performed in all cases. RESULTS: Nerve biopsies of 22 patients were diagnosed as NSVN. The pathological features were vasculitis and predominant axonal degeneration with a varying pattern of myelinated fiber loss. The vasculitic changes were found mainly in small epineural blood vessels. Mononeuritis multiplex and distal symmetrical sensorimotor neuropathy were equally frequent. CONCLUSION: NSVN should be suspected in a case of unexplained polyneuropathy without evidence of systemic involvement. Clinical and neurophysiological studies are essential for the detection of nerve involvement, but the specific diagnosis of NSVN may be missed unless a biopsy is performed.

Adult↗

PubMed2005

Poststreptococcal reactive arthritis with thoracic spine involvement in an adult.

It is controversial whether poststreptococcal reactive arthritis (PSReA) is an entity separate from acute rheumatic fever (ARF) or is a forme fruste of ARF. Although there are many case series of PSReA in children, this entity is not common in adults. We describe an adult patient with polyarthritis and thoracic spine involvement attributed to PSReA.

Anti-Bacterial Agents↗

PubMed2004

Soluble interleukin-6 receptor (sIL-6R) in cerebrospinal fluid of patients with inflammatory and non inflammatory neurological diseases.

IL-6 acts on target cells via the ligand-binding protein interleukin-6 receptor (IL-6R) and the affinity-converting and signal-transducing glycoprotein 130 (gp130). Soluble interleukin-6 receptor (sIL-6R) has an agonistic role because the soluble complex (IL-6/sIL-6R) can activate cells that do not express IL-6R and an antagonistic role as it enhances the inhibitory activity of sgp130. Soluble forms of both receptors, sIL-6R and sgp130, regulate the action of IL-6. sIL-6R was measured by a sensitive enzyme-linked immunosorbent assay in paired sera and cerebrospinal fluid (CSF) from 46 patients with inflammatory neurological diseases (IND), 45 patients with relapsing-remitting multiple sclerosis (RR-MS), 13 patients with primary progressive multiple sclerosis (PP-MS), 17 patients with other non inflammatory neurological diseases (NIND) and 13 mentally healthy individuals--healthy controls (HC). Patients with RR-MS had CSF sIL-6R levels comparable to those from patients with IND, but higher than patients with NIND and HC. A positive correlation between the CSF/serum albumin (QAlb) and CSF sIL-6R levels was observed in IND but not in RR-MS patients indicating that CSF sIL-6R levels in IND patients could be influenced by serum sIL-6R and blood brain barrier (BBB) permeability properties. RR-MS patients had higher values of [CSF/serum sIL-6R:CSF/serum albumin] (sIL-6R index) than IND patients suggesting that in multiple sclerosis (MS), the increase in CSF sIL-6R could be due to intrathecal synthesis of sIL-6R. The finding of increased CSF sIL-6R concentrations (>979 pg/ml) with sIL-6R index (>4.66), in correlation with positive oligoclonal bands in RR-MS patients, suggests that values of sIL-6R index > 4.66 indicate intrathecal increase of sIL-6R and might be used as an indicator of neuroimmunoregulatory and inflammatory processes in the central nervous system (CNS).

Analysis of Variance↗

PubMed2004

Effect of helicobacter pylori infection on the risk of upper gastrointestinal bleeding in users of nonsteroidal anti-inflammatory drugs.

PURPOSE: We evaluated whether infection with Helicobacter pylori, including specific cytotoxic-associated antigen (CagA)-positive strains, increase the risk of upper gastrointestinal bleeding in users of nonsteroidal anti-inflammatory drugs (NSAIDs). METHODS: Cases with upper gastrointestinal bleeding and recent NSAID use, including aspirin, who were admitted during 2001, were compared with age- and sex-matched outpatient controls who had recent NSAID use. H. pylori infection was diagnosed by serum antibodies or the (13)C-urea breath test; and CagA seropositivity was diagnosed by enzyme-linked immunoassay. RESULTS: H. pylori was detected significantly more frequently in cases of bleeding than controls (79% [63/80] vs. 56% [45/80], P = 0.004). Cases of bleeding were more likely than controls to have a history of peptic ulcer (34% [n = 27] vs. 13% [n = 10], P = 0.003), previous upper gastrointestinal bleeding (19% [n = 15] vs. 6% [n = 5], P = 0.03), recent dyspepsia (29% [n = 23] vs. 15% [n = 12], P = 0.06), and <3 months of NSAID use (58% [n = 46] vs. 40% [n = 32], P = 0.04). CagA positivity was not associated with gastrointestinal bleeding. In a multivariate analysis, H. pylori infection was the only significant risk factor for upper gastrointestinal bleeding (odds ratio = 1.7; 95% confidence interval: 1.2 to 2.5; P = 0.004). CONCLUSION: H. pylori infection almost doubles the risk of upper gastrointestinal bleeding among users of NSAIDs.

Aged↗