Selenium has a protective role in caspase-3-dependent apoptosis induced by H2O2 in primary cultured pig thyrocytes

OBJECTIVE: Hydrogen peroxide (H2O2), necessary for thyroid hormonogenesis, is produced at the apical surface of the thyroid follicular epithelium. Excess H2O2 is potentially cytotoxic and may contribute to the development of hypothyroidism, e.g. in severe selenium deficiency. Yet it is unclear how H2O2 contributes to thyroid cell death. DESIGN AND METHODS: H2O2-induced apoptosis and necrosis were studied in primary cultured pig thyroid cells. Glutathione peroxidase (GPx) activity was altered by culture in low serum with or without selenite substitution. Apoptosis was evaluated by spectrofluorometric measurement of caspase-3-specific substrate cleavage, and by analysis of DNA fragmentation by agarose gel electrophoresis. Necrosis was detected by 51Cr release from prelabeled cells. RESULTS: Exogenous H2O2 dose-dependently (100-400 micromol/l) activated caspase-3 within 3-12 h, and DNA degradation was observed after 24 h. The potency of H2O2 to induce apoptosis was low compared with that of staurosporine, a strong proapoptotic agent. H2O2-treated cells with reduced GPx activity showed increased caspase-3 activation. Incubation of serum-starved cells with selenite (10-100 nmol/l) normalized the GPx activity and reduced the activation of caspase-3 by H2O2. High H2O2 concentrations (400-800 micromol/l) were required to obtain necrosis. The H2O2-induced necrosis was exaggerated by both low GPx activity and catalase inhibition. CONCLUSIONS: Cytotoxic effects of H2O2 on thyroid cells include caspase-3-dependent apoptosis that occurs at H2O2 concentrations insufficient to induce necrosis. Selenium deficiency aggravates the apoptotic response, probably due to impaired capacity of GPx to degrade H2O2.     

Functional and Physiologic Assessment of the Colonic Reservoir or Side-to-End Anastomosis After Low Anterior Resection for Rectal Cancer: A Two-Year Follow-Up

PURPOSE Functional disturbances are common after anterior resection for rectal cancer. This study was designed to compare functional and physiologic outcome after low anterior resection and total mesorectal excision with a colonic J-pouch or a side-to-end anastomosis.METHODS Functional and physiologic variables were analyzed in patients randomized to a J-pouch (n = 36) or side-to-end anastomosis (n = 35). Postoperative functional outcome was investigated with questionnaires. Anorectal manometry was performed preoperatively and at six months, one year, and two years postoperatively.RESULTS There was no statistical difference in functional outcome between groups at two years. Maximum neorectal volume increased in both groups but was approximately 40 percent greater at two years in pouches compared with the side-to-end anastomosis. Anal sphincter pressures volumes were halved postoperatively and did not recover during follow-up of two years. Male gender, low anastomotic level, pelvic sepsis, and the postoperative decrease of sphincter pressures were independent factors for more incontinence symptoms.CONCLUSIONS Colonic J-pouch and side-to-end anastomosis gives comparable functional results two years after low anterior resection. Neorectal volume had no detectable influence on function. There was a pronounced and sustained postoperative decrease in sphincter pressures.Supported by the Stockholm County Council, Public Health and Medical Services Committee and the Swedish Research Council, grant #09101.Reprints are not available.     

Lower limb motor restlessness in Asperger's disorder, measured using actometry

The movement disturbances and brain imaging findings in Asperger's disorder (AD) suggest a dopaminergic deficit in movement regulation. Movement disorders of different etiologies have been quantified and specified with actometry. We compared 10 AD patients with 10 healthy controls, measuring their rest-activities by actometry. The lower limb motor activity was significantly higher in the AD group. They also displayed a rhythmic, periodic movement pattern similar to akathisia. These findings suggest a hypothesis of idiopathic akathisia and a special sensitivity to adverse effects of neuroleptic drugs.     

Clinical significance of glutamic acid decarboxylase antibodies in patients with epilepsy

Purpose: Glutamic acid decarboxylase antibodies (GADAs) have been detected in patients with epilepsy, but the clinical determinants of epilepsy associated with GADA have not been defined. Methods: We analyzed GADA with a radioimmunoassay in sera of 253 well‐characterized patients with epilepsy and 200 control subjects. The positive samples were confirmed by immunohistochemistry and western blotting (WB). Sera were screened for other autoantibodies. Results: GADA were detected in 15 patients (5.9%) and in three control subjects (1.5%) (p = 0.026). Seven patients (2.8%) had high GADA titers [≥1,000 relative units (RUs)/ml], six of whom had temporal lobe epilepsy (TLE). All three GADA‐positive control subjects had low titers. Two of the five patients with high GADA titers and available cerebrospinal fluid (CSF) samples had intrathecal synthesis (IS) of GADA; one patient had CSF oligoclonal bands. The prevalence of increased levels of GADA tended to be higher in patients with TLE than in patients with extra‐TLE [odds ratio (OR) 1.32, 95% confidence interval (CI) 0.39–4.42; p = 0.657]. The patients with high GADA titers had significantly higher number of other autoantibodies compared to the patients with low GADA titers (p = 0.001) and the patients with normal GADA (p < 0.001). Discussion: High GADA titers were present in a subgroup of patients; close to 90% had TLE. The immunologic profile of these patients suggests that the most probable origin of their epilepsy is autoimmune. A positive IS of GADA may be a marker of an ongoing immune response that could identify those patients in whom a trial with immunosuppressive therapy might be warranted.     

Histamine receptors in the isolated human middle meningeal artery. A comparison with cerebral and temporal arteries

The subtypes of histamine receptors mediating dilatation of human meningeal arteries have been tested in vitro, using "selective" antagonists, and compared with cerebral and temporal arteries previously examined. Dilatory responses were tested after preconstriction with prostaglandin F2 alpha. Both mepyramine and cimetidine caused a parallel shift to the right of the histamine concentration-response curve, suggesting the presence of both H1- and H2-receptors. Combined treatment with mepyramine and cimetidine caused further displacement of the concentration-response curve to the right. Schild analysis indicated pA2 values of 6.3 for cimetidine and 9.8 for mepyramine in situations of near complete blockade of either of the receptors. Both H1- and H2-receptors seem of importance for the histamine-induced dilatation in meningeal arteries and neither appear to dominate. The data considered in conjunction with our previous findings support the finding that experimental histamine-induced headache due to vasodilatation is intracranial of origin.