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Some experiments to study the influence of electrophoresis conditions and subsequent LA-ICP-MS (laser ablation-inductively coupled plasma mass spectrometry) determination of two metal-binding proteins with different metal-protein affinities (superoxide dismutase, containing Cu and Zn, and alcohol dehydrogenase, containing Zn) are performed. In metal-binding proteins with weak metal-protein affinities, metal losses can happen during electrophoretic separation. It has been demonstrated that the detection of these metals bound to the proteins depends, not only on the nature of the electrophoretic process (naturing or non-denaturing) and post-separation gel treatment, but also on the trailing ion chosen and current applied in the electrophoretic method used. Non-denaturing methods are preferred to denaturing ones in the case of alcohol dehydrogenase being BN-PAGE (Blue Native-Polyacrylamide Gel Electrophoresis) with the use of Tricine as trailing ion the most recommended method. The concentration obtained for Zn in ADH applying BN-PAGE-LA-ICP-MS was 2.6+/-0.30 mg g(-1) very close to the one obtained for ADH solution by ICP-MS (3+/-0.23 mg g(1)). For superoxide dismutase either denaturing or non-denaturing electrophoresis conditions can be used, but a denaturing method based on the use of Tricine as trailing ion is recommended to preserve metals-protein binding when the use of non-denaturing conditions must be avoided. The found concentration for Cu and Zn in SOD after applying SDS-Tris-Tricine-PAGE-LA-ICP-MS was 2.5+/-0.33 and 2.4+/-0.37 mg g(-1) respectively, more or less close (especially for Cu) to the one obtained in SOD solution by ICP-MS (3+/-0.21 and 3.7+/-0.32 mg g(-1) for Cu and Zn). We observe that as higher current is applied the possibility of metal-protein binding losses is higher. In all cases staining of the gel prior to LA-ICP-MS is not recommended., ((c) 2009 Elsevier B.V. All rights reserved.)

The purpose of this research was to study traumatic and dissociative experiences in a sample of Spanish psychotic patients. A total of 37 psychotic patients filled out the Dissociative Experiences Scale (E. B. Carlson & F. W. Putnam, 1993), a questionnaire on traumas (J. R. E. Davidson, D. Hughes, & D. G. Blazer, 1990), and the Positive and Negative Syndrome Scale delusion and hallucinations items (S. R. Kay, L. A. Opler, & J. P. Lindenmayer, 1988). The results showed that 40.5% of the subjects in the sample had undergone at least 1 traumatic experience as children and 64.9% had as adults. Patients with hallucinations had experienced a higher mean number of childhood traumatic experiences than patients without hallucinations. No significant difference in the mean number of traumatic events was found between patients with and without delusions. There was no significant difference in the mean number of adulthood traumatic events between patients with and without hallucinations and delusions. Subjects with childhood traumas scored higher on the Dissociative Experiences Scale than those who had had such experiences as adults. Patients with hallucinations and delusions also scored higher on the dissociation scale than patients who did not show those positive psychotic symptoms.

An experimental approach to evaluate the capabilities and limitations of polyacrylamide gel electrophoresis (PAGE) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for quantitative elemental speciation is presented. Two metalloproteins (superoxide dismutase, containing Cu and Zn, and thyroglobulin, containing I) with high binding affinity for metals, and metal-dissolved organic matter (DOM) complexes (from a compost leachate sample) which show different types of metal binding are studied. Iodine can be quantitatively detected in thyroglobulin after PAGE-LA-ICP-MS using either sodium dodecyl sulfate (SDS) PAGE or native PAGE. However, detection of Cu and Zn in superoxide dismutase after PAGE-LA-ICP-MS depends on the conditions of the PAGE method because possible metal losses can occur (either with SDS-PAGE or with native PAGE). The use of PAGE-LA-ICP-MS to study the contribution of DOM to the mobilization of metals from environmental samples is possible, but it depends also on the PAGE separation conditions owing to disequilibrium effects of metal-DOM complexes.

The capabilities of 2 quantitative polymerase chain reaction (PCR) assays for detecting pulmonary aspergillosis were analyzed. Both methodologies were real-time (RT) based and were compared with quantitative cultures and galactomannan (GM) antigen detection in a rabbit model of invasive aspergillosis. A total of 106 samples including blood, serum, lung, and brain from 3 controls and 9 infected New Zealand rabbits were analyzed. The RT-PCR methodologies were an Aspergillus fumigatus-specific assay using fluorescent resonance energy transfer technology targeting a highly conserved region of the fungal 18S rRNA gene and a panfungal assay to amplify the internal transcribed spacer regions 1 and 2 from fungal rRNA gene complex, employing SYBRGreen fluorescent dye as a detector. The specificity for both PCR base assays, culture, and GM determination was 100%. The sensitivity of the specific PCR assay was 88.9% in lung samples, 66.6% in serum, 55.5% in blood, and 33.3 in brain specimens. The panfungal assay had a sensitivity of 33.3% in lung and serum samples, being brain and blood specimens invariably negative. Otherwise, 100% of the lungs resulted positive for culture, and all serum samples showed a GM index above 1.0 after 2 days of infection. The specific RT-PCR assay is a reliable technique to detect A. fumigatus DNA in vivo comparable to cultures and GM determination. The panfungal RT-PCR assay exhibited low sensitivity to diagnose invasive aspergillosis in rabbits advising against its clinical introduction.

Background and Objectives: The detection of PML-RAR by reverse transcription (RT) polymerase chain reaction (PCR) in acute promyelocytic leukemia (APL) patients who are in hematologic remission influences therapeutic decision making in several trials. In the light of this, the Spanish group has recently designed an external quality assessment program (EQAP) of RT-PCR detection of PML-RAR, which includes a study of sensitivity of the participating laboratories., Design and Methods: Eighteen laboratories were involved in the program. Ten laboratories followed the method of Biondi et al., 5 employed that of Borrow et al. and the 3 remaining used other protocols. The sensitivity was studied in five rounds of quality control. The first two shipments consisted of dilutions of NB4 RNA into non-APL RNA. The third round consisted of serial dilutions of the NB4 cell line into HL60 cells. The fourth and five rounds consisted of plasmid dilutions containing the bcr1 and bcr3 PML-RAR isoforms., Results: The results showed that the distinct methods allow detection of the PML-RAR hybrid up to a dilution of 10(-4), and exceptionally, up to 10(-5). The laboratories following the method of Biondi et al. usually detected the 10(-3) dilution and less frequently the 10(-4) one, whereas those using other methods usually detected PML-RAR transcript in the 10(-4) dilution, and less commonly in the 10(-5) dilution. However, each of the PCR methods used by EQAP participating laboratories successfully detected at least 50 copies of PML-RAR alpha fusion transcript in plasmid dilution controls., Interpretation and Conclusions: The results point to heterogeneous sensitivity amongst participating laboratories. This may reflect differences in methodology, although variations in sample quality may also account for discrepant findings.

Background and Methods: Cushing's syndrome is rare in children and adolescents. We analyzed the clinical presentation, diagnostic evaluation, and treatment of 59 patients with Cushing's syndrome between the ages of 4 and 20 years who were admitted to the National Institutes of Health during the period from 1982 to 1992. The cause of hypercortisolism was identified by low- and high-dose dexamethasone suppression tests, the ovine corticotropin-releasing hormone (CRH) stimulation test, imaging studies, and bilateral sampling of the inferior petrosal sinuses combined with administration of CRH., Results: Fifty patients had Cushing's disease, six had primary adrenal disease, and three had ectopic corticotropin secretion. The initial signs were excessive weight gain in 90 percent of the patients and growth retardation in 83 percent. Most patients (81 percent) had normal bone age at the time of diagnosis. Forty-seven percent had hypertension, whereas only 19 percent had mental or behavioral problems. The high-dose dexamethasone suppression test and the CRH stimulation test identified 68 and 80 percent, respectively, of the patients with Cushing's disease. Magnetic resonance imaging of the pituitary indicated the presence of tumor in 52 percent of the patients with pituitary adenomas. The maximal central-to-peripheral ratio of plasma corticotropin during sampling of the interior petrosal sinuses was > or = 2.5 in all the patients with Cushing's disease and < 2.5 in those with ectopic corticotropin secretion. Remission of hypercortisolism was achieved in 48 of the 49 patients who underwent transsphenoidal surgery for Cushing's disease, in all 6 of the patients who underwent adrenalectomy for primary adrenal disease, and in the 2 patients in whom the ectopic source of corticotropin could be identified., Conclusions: Weight gain and growth retardation are common clinical characteristics of Cushing's syndrome in children and adolescents. Diagnostic evaluation of such patients with CRH stimulation alone and combined with inferior petrosal sinus sampling and imaging studies is accurate, and therapy is usually successful.

Growth retardation to complete growth arrest is the hallmark of Cushing's syndrome in children. The major mechanism for this has been considered the glucocorticoid-induced resistance of target tissues to insulin-like growth factor-I (IGF-I) and other growth factors. The purpose of this study was to examine the GH secretory dynamics of patients with Cushing's disease before and up to 12 months after their cure by transsphenoidal adenomectomy. In 14 patients, blood sampling every 20 min over 24 h for determination of plasma GH was performed before and 10-11 days and 3, 6, and 12 months after therapy. These patients also underwent arginine infusion and L-dopa stimulation tests and had measurements of morning baseline GH-binding protein (GHBP), IGF-I, and IGF-binding protein-3 (IGFBP-3) plasma concentrations. Fourteen sex- and pubertal stage-matched normal volunteers were used as controls. Before therapy, the patient group had an increased body mass index (31.5 +/- 5 kg/m2) and markedly decreased plasma mean 24-h GH concentration, mean peak height, and peak area values, with pulse frequency (mean number of peaks) similar to that in the controls. GH values after arginine and L-dopa stimulation were also subnormal in many of these patients, with 2 of 8 and 8 of 10 failing to show GH responses greater than 7 ng/mL in the respective test. In spite of these findings, plasma concentrations of IGF-I, IGFBP-3, and GHBP were within the normal range in these patients. Surprisingly, a pattern of GH suppression similar to that observed in patients with active disease was also seen in patients who were studied 10-11 days and 3, 6, and 12 months after their cure, when their body mass indexes were progressively normalizing, being relatively stable at 10 days, 26.9 +/- 3.8 kg/m2 at 3 months, and 24.8 +/- 3.3 kg/m2 at 12 months. In these patients, plasma IGF-I and GHBP remained normal, whereas IGFBP-3 decreased significantly, albeit within the normal range. The growth rate of 4 patients who were Tanner stage III or below and had not completed their growth at the time of the study increased the year after surgical cure. These findings suggest that patients with Cushing's disease have marked GH suppression during their illness, which, however, does not appear to be a major contributor to the growth suppression observed in this condition. GH hyposecretion continues for at least a year during convalescence, in spite of significant increases in the growth rate in all growing patients.(ABSTRACT TRUNCATED AT 400 WORDS)

Patients cured from endogenous Cushing syndrome usually develop postoperative adrenal suppression in the year ensuing surgery. To define whether the pituitary corticotroph is the rate limiting step in the postoperative recovery of this secondary/tertiary form of adrenal insufficiency, we examined surgically cured patients with Cushing syndrome 10 days, 3 months, and 6-12 months after surgery, by administering ovine CRH (oCRH) iv at the dose of 1 microgram/kg.h over 24 h. The pituitary corticotroph of these patients responded vigorously to oCRH, with ACTH concentrations reaching above the normal range at all three times of testing. Parallel measurements of cortisol in nonadrenalectomized patients demonstrated subnormal adrenal responsiveness at 10 days and 3 months and normalization at 6-12 months after surgery. The circadian rhythm of ACTH was maintained postoperatively at 10 days and 6-12 months, and the circadian rhythm of cortisol was also present at 6-12 months after surgery, in spite of the constant infusions of pharmacological doses of oCRH, suggesting that factors other than CRH secretion regulate this rhythm. We conclude that the corticotroph is not the rate limiting step in the recovery of the hypothalamic-pituitary-adrenal axis from glucocorticoid-induced adrenal suppression, and that the locus of the defect resides in the hypothalamic CRH neuron and/or its higher regulatory inputs.

Activation of serotonergic neurotransmission has been shown to increase plasma beta-endorphin-like immunoreactivity (beta-End-LI). To study the mechanism(s) of this action, we measured the effects of 3 potent serotonin (5-HT) agonists with different structures and 5-HT receptor binding profiles in conscious unrestrained Sprague-Dawley rats in vivo and in dispersed anterior pituicytes in vitro. The 5-HT1A agonist, 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT), the 5-HT1C agonist, m-chlorophenylpiperazine (m-CPP), and the 5-HT2 agonist, 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI), all markedly increased beta-End-LI in plasma in vivo. All 3 responses were blocked by dexamethasone pretreatment. Pituitary stalk transection (PST), as well as pretreatment with rabbit serum hyperimmune against rat corticotropin-releasing hormone (CRH, TS-6) completely abolished beta-End-LI response to 8-OH-DPAT and attenuated the responses by about 60% to DOI. Responses to m-CPP were markedly attenuated in PST rats, but pretreatment with TS-6 had no significant effect. To examine whether vasopressin (AVP) might be involved in the CRH neutralizing antibody-resistant beta-End-LI responses after m-CPP and DOI, we measured AVP concentrations after each agonist, m-CPP, but not DOI or 8-OH-DPAT, significantly elevated circulating AVP levels. As a proof of direct pituitary effect, DOI markedly stimulated beta-End-LI release from the anterior pituitary cell culture preparation in vitro. It was approximately as potent as CRH in the picomolar range, m-CPP was much less effective than DOI, while 8-OH-DPAT did not stimulate beta-End-LI release in vitro.(ABSTRACT TRUNCATED AT 250 WORDS)

We studied the effects of tumor necrosis factor-alpha (TNF alpha), a macrophage-derived pleiotropic cytokine produced during the inflammatory/immune response, on the function of the hypothalamic-pituitary-adrenal (HPA) axis of the rat. Intravenous injections of TNF alpha stimulated plasma ACTH and corticosterone secretion in a dose-dependent fashion. This effect was inhibited by a rat CRH antiserum that was administered to the rats 1 h before the TNF alpha injections. This suggested that CRH is a major mediator of the HPA axis response to TNF alpha. We subsequently evaluated the ability of TNF alpha to influence CRH and ACTH secretion in vitro by explanted rat hypothalami in organ culture and by dispersed rat anterior pituicytes in primary culture respectively. Hypothalami were incubated for 40 min with graded concentrations of TNF alpha (10 pM to 1 microM). This cytokine stimulated CRH secretion in a dose-dependent fashion, with an EC50 of 6.7 x 10 pM (P less than 0.05). Preincubation of hypothalamic explants with dexamethasone, indomethacin (1 microM), eicosatetraynoic acid (10 microM), or nordihydroguaiaretic acid (30 microM) resulted in inhibition of TNF alpha-stimulated CRH secretion (P less than 0.05). Interestingly, 4-h incubation with TNF alpha had no effect on ACTH secretion from rat anterior pituicytes at a concentration of 10 nM. Higher concentrations of TNF alpha (100 nM and 1 microM), however, elicited a dose-dependent increase in the ACTH concentration in the medium. Our results suggest that TNF alpha represents one of the immune response mediators that directly or via stimulation of other cytokines act as activators of the HPA axis during immune/inflammatory reactions. This effect appears to be glucocorticoid suppressible and eicosanoid mediated. The primary site of action of TNF alpha appears to by the hypothalamic CRH-secreting neuron. Some pituitary and adrenal effects of TNF alpha, however, cannot be excluded.

Several lines of experimental evidence suggest that acetylcholine and other cholinergic agonists are excitatory to the hypothalamic-pituitary-adrenal (HPA) axis. To examine the site on the HPA axis that is stimulated by cholinergic agents, we evaluated the in vivo and in vitro effects of the muscarinic cholinergic agonist arecoline in intact and pituitary stalk-transected rats as well as on isolated rat hypothalami, dispersed anterior pituicytes, and adrenocortical cells in culture. Arecoline, injected iv to catheterized, freely moving male Sprague-Dawley rats, stimulated plasma ACTH and corticosterone release in a dose-dependent fashion. The muscarinic cholinergic antagonist atropine significantly blunted the ACTH response to arecoline. Pituitary stalk transection led to diminished plasma ACTH and corticosterone responses to arecoline. Similarly, previous administration of anti-CRH serum significantly blunted these responses. These findings suggest that arecoline stimulates the HPA axis centrally, mainly via secretion of CRH. This hypothesis was confirmed by the dose-dependent ability of arecoline to cause hypothalamic CRH secretion in vitro, an effect antagonized by atropine, and its failure to elicit ACTH and corticosterone secretion by dispersed anterior pituicytes and adrenocortical cells in culture, respectively. These data suggest that the muscarinic cholinergic agonist arecoline stimulates the HPA axis in the rat and that this effect is mediated mainly by the release of endogenous CRH. Arecoline, therefore, appears to be a compound suitable to selectively evaluate the responsiveness of the central component of the HPA axis.

Primary pigmented nodular adrenocortical disease (PPNAD) is a rare cause of Cushing syndrome in infants, children, and young adults. It is characterized by non-adrenocorticotropic hormone-dependent hypersecretion of cortisol by multiple, pigmented nodules of hyperplastic adrenocortical cells. With a single exception, adrenal glands have been described as normal with computed tomography (CT) in all previous series. Eight patients had Cushing syndrome due to surgically proved PPNAD. Four of the eight patients had stigmas of Carney complex (lentigines, calcified Sertoli cell tumors of the testes, and cardiac and soft-tissue myxomas). CT and/or magnetic resonance (MR) imaging demonstrated unilateral or bilateral nodularity in five of six patients examined. Macronodules (greater than 10 mm) were seen in the two oldest patients. As the clinical presentation of Cushing syndrome in this group of patients may be atypical (severe osteoporosis or short stature), the detection of multiple, small adrenocortical nodules with CT or MR imaging supports, or may even suggest, the diagnosis of PPNAD.