Plasma levels of neuropeptides in Alzheimer's disease.

BACKGROUND: In the central nervous system, several neuropeptides are believed to be involved in the pathophysiology of Alzheimer's disease (AD). Indeed, previous studies have documented that glucagon-like peptide 1 (GLP-1) possesses neurotropic properties and can reduce amyloid-beta peptide levels in the brain in vivo. Moreover, the concentrations of neuropeptide Y (NPY) seem to be altered in the cerebrospinal fluid of patients with AD and in subjects with major depression. Finally, among the modifications induced by aging, a dysregulation of the ghrelin-growth hormone (GH) system has been reported. METHODS: We investigated the plasma concentrations of these neuropeptides in 14 subjects with AD. Data obtained from these patients were compared with data from an age- and weight-matched healthy group. RESULTS: No significant differences were found between the two groups in relation to plasma levels of GLP-1, NPY, ghrelin and GH. Peripheral NPY concentrations were positively correlated with ghrelin levels in both groups, and with plasma GLP-1 concentration only in controls. CONCLUSION: On the basis of our results, peripheral levels of these neuropeptides seem not to serve as biochemical markers of AD.     

Inherited Neurodegenerative Disorders Caused by CAG/Polyglutamine Tract Expansions: Symposium Introduction

At the beginning of this decade, the American Association of Neurology decided that the 1990's should be labelled "the decade of the brain" for expected advances in our understanding of neurological disorders and neuroscience. By the end of this decade, clinicians and researchers who work in the field of inherited neurological disorders might well remember the 1990's as "the decade of the trinucleotide repeat". At the time of writing this introduction, eleven inherited neurological disorders have been found to be caused by expansions of trinucleotide repeats, and a twelfth trinucleotide repeat expansion mutation has been identified (6), although the gene containing this mutant triplet repeat has not been cloned to our knowledge (Table 1).     

Conjunctival provocation tests in suspected allergic conjunctivitis: a clinical study

We examined 57 patients who showed conjunctivitis suspected of allergic pathogenesis with skin radioallergosorbent (RAST) and conjunctival provocation tests (CPT). Our aim was to define statistical correlations between those tests and their exact values for the right diagnosis. Our data show that CPT is more sensitive than skin tests or RAST to ascertain the origin of conjunctivitis.     

Randomized Trial of Basiliximab Induction versus Steroid Therapy in Pediatric Liver Allograft Recipients Under Tacrolimus Immunosuppression

Avoidance of corticosteroids could be beneficial after pediatric liver transplantation (LTx). To test this hypothesis, we performed a randomized prospective study to compare immunosuppression with tacrolimus (TAC) and steroids versus TAC and basiliximab (BAS) after pediatric LTx. Seventy-two patients were recruited, 36 receiving TAC and steroids and 36 TAC and BAS. The primary endpoint was the occurrence of the first rejection episode. Secondary endpoints were the cumulative incidence and severity of rejection, patient and graft survival, and incidence of adverse events. Overall 1-year patient and graft survival rates were 91.4% and 85.5% in the steroid group, and 88.6% and 80% in the BAS group (p = NS). Patients free from rejection were 87.7% in the BAS group and 67.7% in the steroid group (p = 0.036). The use of BAS was associated with a 63.6% reduction in incidence of acute rejection episodes. Overall incidence of infection was 72.3% in the steroid group and 50% in the BAS group (p = 0.035). We conclude that the combination of TAC with BAS is an alternative to TAC and steroid immunosuppression in pediatric LTx, which allows for a significant reduction in the incidence of acute rejection and infectious complications.     

Relationship between resting alpha activity and the ERPs obtained during a highly demanding selective attention task.

In spite of previous reports on the relationship between ongoing EEG and ERPs, there remains a lack of agreement on the nature of their nexuses. The aim of the present study was to evaluate the relationship between resting EEG and the ERP components in two groups of healthy subjects with different levels of performance in a highly demanding selective visual attention task. Young adults were classified according to the amount of their correct responses in the task, into high (HP; averaged hits (AH): 86%) and low performance groups (LP; AH: 59%). EEG was recorded during rest, prior to task performance and absolute (AP) and relative power (RP), as well as inter- (rTER) and intrahemispheric (rTRA) correlation were calculated. ERPs during task performance were also obtained and their amplitude and latency measures were assessed. Results showed that individuals with better behavioral performance had a higher synchronization between both hemispheres during rest as well as higher amplitude and shorter latencies of N2 and P3. Principal Component Analysis revealed that alpha2 AP and RP were inversely related to P2 and N2 latency. Higher values of alpha1 and alpha2 rTER were clustered with higher P3 amplitude and shorter reaction time. In conclusion, the differences in the cortical organization of HP and LP at rest (EEG) seem to be associated to the way the brain reacts during information processing (ERPs).     

Loss of endogenous androgen receptor protein accelerates motor neuron degeneration and accentuates androgen insensitivity in a mouse model of X-linked spinal and bulbar muscular atrophy

Human Molecular     

Postnephrectomy pseudoaneurysm with arteriovenous fistula

Sonography detected a paraaortic pulsatile tubular mass in a patient 10 years after “stump” nephrectomy, which was subsequently confirmed as a renal artery-renal vein fistula by computed tomography, angiography, and laparotomy.     

Mutations in the alpha subunit of the stimulatory regulatory protein of adenylyl cyclase (Gs) in human GH-secreting pituitary adenomas. Biochemical, clinical, and morphological aspects

Very recently a subset of human GH-secreting pituitary adenomas carrying a somatic mutation in the alpha subunit of the stimulatory regulatory protein of adenylyl cyclase (Gs) was identified. In all these tumors (Group 2; about 30% of all the GH secreting tumors studied) the alpha s cDNAs contained mutations; in 8 tumors mutations replaced Arginine 201 with either Cystein or Histidine while in the remaining tumors Glutamine 227 was replaced by either Arginine or Leucine. No mutations were observed in the remaining adenomas (Group 1). The two mutations caused a constitutive activation of adenylyl cyclase and a turn on of cAMP synthesis by inhibiting GTPase activity. The transformed phenotype was reflected in adenomatous cells with high rate of cAMP production and in vitro GH secretion. No difference in age, sex, clinical features, duration of the disease and cure rate were observed between the patients without (Group 1) or with alpha s mutation (Group 2), while higher serum GH levels and smaller tumor size were present in Group 2 patients. Moreover, hypersecretory activity in Group 2 tumors was also apparent at electron microscopy; cells of Group 2 tumors were densely granulated and showed prominent rough endoplasmic reticulum and Golgi complex. With respect to Group 1, Group 2 patients were less responsive to GH-releasing hormone (GHRH), while they were more sensitive to somastostatin. The former finding is in agreement with the hypothesis that the oncogenic proteins mimic the effects of extracellular growth factors, so removing the requirement for GHRH; the latter might explain the low rate of tumor growth as due to the counteracting role of endogenous inhibitory factors.