Electron photodetachment dissociation of DNA anions with covalently or noncovalently bound chromophores

Double stranded DNA multiply charged anions coupled to chromophores were subjected to UV-Vis photoactivation. in a quadrupole ion trap mass spectrometer. The chromophores included noncovalently bound minor groove binders (activated in the near UV), noncovalently bound intercalators (activated with visible light), and covalently linked fluorophores and quenchers (activated at their maximum absorption wavelength). We found that the activation of only chromophores having long fluorescence lifetimes did result in efficient electron photodetachment from the DNA complexes. In the case of ethidium-dsDNA complex excited at 500 nm, photodetachment is a multiphoton process. The MS3 fragmentation of radicals produced by photodetachment at lambda = 260 nm (DNA excitation) and by photodetachment at lambda > 300 nm (chromophore excitation) were compared. The radicals keep no memory of the way they were produced. A weakly bound noncovalent ligand (m-amsacrine) allowed probing experimentally that a fraction of the electronic internal energy was converted into vibrational internal energy. This fragmentation channel was used to demonstrate that excitation of the quencher DABSYL resulted in internal conversion, unlike the fluorophore 6-FAM. Altogether, photodetachment of the DNA complexes upon chromophore excitation can be interpreted by the following mechanism: (1) ligands with sufficiently long excited-state lifetime undergo resonant two-photon excitation to reach the level of the DNA excited states, then (2) the excited-state must be coupled to the DNA excited states for photodetachment to occur. Our experiments also pave the way towards photodissociation probes of biomolecule conformation in the gas-phase by Forster resonance energy transfer (FRET)

Efficacy and safety of high-dose long-acting repeatable octreotide as monotherapy or in combination with pegvisomant or cabergoline in patients with acromegaly not adequately controlled by conventional regimens: results of an open-label, multicentre study

Introduction: Long-acting repeatable (LAR) octreotide i.m. is a potent, synthetic somatostatin analogue (SSA) that requires less frequent dosing and offers quality of life (QoL) benefits in acromegaly patients compared to its shorter-acting predecessor. This study investigated the efficacy and safety of high-dose Sandostatin® LAR® as monotherapy or in combination with pegvisomant or cabergoline in acromegalic patients with pituitary adenomas following previous failure of conventional SSA treatment. Material and methods: After three months of high-dose Sandostatin® LAR® monotherapy (40 mg), patients who achieved biochemical control (n = 7) continued to receive the same treatment for an additional four months, whereas uncontrolled patients were randomised to receive high-dose Sandostatin® LAR® in combination with pegvisomant (n = 31) or cabergoline (n = 32). Outcomes included biochemical response at eight months, QoL, and safety. Results: After three months, 3 of 68 (4.4%) evaluable patients achieved a biochemical control (BC) as assessed by levels of growth hormone and insulin-like growth factor-1. At eight months, 4 of 67 (6.0%) patients achieved BC, including one receiving monotherapy and three receiving Sandostatin® LAR® plus cabergoline. Partial response rate, improvements in acromegaly signs and symptoms, and changes in QoL were similar for all three groups. All treatments were well tolerated with a slight excess of adverse events in the combination arms. There were no deaths or serious adverse events leading to treatment discontinuation. Conclusion: These data demonstrate that high-dose Sandostatin® LAR® as monotherapy or in combination with pegvisomant or cabergoline is a feasible salvage option in patients with pituitary adenomas not adequately controlled on conventional SSA regimens

efficacy and safety of high dose long acting repeatable octreotide as monotherapy or in combination with pegvisomant or cabergoline in patients with acromegaly not adequately controlled by conventional regimens results of an open label multicenter study

Introduction: Long-acting repeatable (LAR) octreotide i.m. is a potent, synthetic somatostatin analogue (SSA) that requires less frequent dosing and offers quality of life (QoL) benefits in acromegaly patients compared to its shorter-acting predecessor. This study investigated the efficacy and safety of high-dose Sandostatin® LAR® as monotherapy or in combination with pegvisomant or cabergoline in acromegalic patients with pituitary adenomas following previous failure of conventional SSA treatment. Material and methods: After three months of high-dose Sandostatin® LAR® monotherapy (40 mg), patients who achieved biochemical control (n = 7) continued to receive the same treatment for an additional four months, whereas uncontrolled patients were randomised to receive high-dose Sandostatin® LAR® in combination with pegvisomant (n = 31) or cabergoline (n = 32). Outcomes included biochemical response at eight months, QoL, and safety. Results: After three months, 3 of 68 (4.4%) evaluable patients achieved a biochemical control (BC) as assessed by levels of growth hormone and insulin-like growth factor-1. At eight months, 4 of 67 (6.0%) patients achieved BC, including one receiving monotherapy and three receiving Sandostatin® LAR® plus cabergoline. Partial response rate, improvements in acromegaly signs and symptoms, and changes in QoL were similar for all three groups. All treatments were well tolerated with a slight excess of adverse events in the combination arms. There were no deaths or serious adverse events leading to treatment discontinuation. Conclusion: These data demonstrate that high-dose Sandostatin® LAR® as monotherapy or in combination with pegvisomant or cabergoline is a feasible salvage option in patients with pituitary adenomas not adequately controlled on conventional SSA regimens

Human urocortin II, a selective agonist for the type 2 corticotropinreleasing factor receptor, decreases feeding and drinking in the rat

ABSTRACT Corticotropin-releasing factor (CRF) has been hypothesized to modulate consummatory behavior through the Type 2 CRF (CRF 2 ) receptor. However, behavioral functions subserved by the CRF 2 receptor remain poorly understood. Recently, human urocortin II (hUcn II), a selective CRF 2 receptor agonist, was identified. To study the effects of this neuropeptide on ingestive behavior, we examined the effects of centrally infused hUcn II (i.c.v. 0, 0.01, 0.1, 1.0, 10.0 g) on the microstructure of nosepoke responding for food and water in nondeprived, male rats. Malaise-inducing properties of the peptide were monitored using conditioned taste aversion (CTA) testing. To identify potential sites of action, central induction of Fos protein expression was examined. hUcn II dose dependently reduced the quantity and duration of responding for food and water at doses lower (0.01-1.0 g) than that forming a CTA (10 g). Effects were most evident during hours 4 to 6 of the dark cycle. Meal pattern analysis showed that hUcn II potently (0.1 g) increased the satiating value of food. Rats ate and drank smaller and shorter meals without changing meal frequency. Rats also ate more slowly. hUcn II induced Fos in regions involved in visceral sensory processing and autonomic/neuroendocrine regulation and resembling those activated by appetite suppressants. hUcn II is a promising neuropeptide for investigating the role of the CRF 2 receptor in ingestive behavior. Corticotropin-releasing factor (CRF) is hypothesized to mediate behavioral, autonomic, endocrine, and immunological responses to stres

CT Characteristics of Pheochromocytoma: Relevance for the Evaluation of Adrenal Incidentaloma.

BACKGROUND: Up to 7% of all adrenal incidentalomas (AIs) are pheochromocytomas (PCCs). In the evaluation of AI, it is generally recommended that PCC be excluded by measurement of plasma-free or 24-hour urinary fractionated metanephrines. However, recent studies suggest that biochemical exclusion of PCC not be performed for lesions with CT characteristics of an adrenocortical adenoma (ACA). AIM: To determine the proportion of PCCs with ACA-like attenuation or contrast washout on CT. METHODS: For this multicenter retrospective study, two central investigators independently analyzed the CT reports of 533 patients with 548 histologically confirmed PCCs. Data on tumor size, unenhanced Hounsfield units (HU), absolute percentage washout (APW), and relative percentage washout (RPW) were collected in addition to clinical parameters. RESULTS: Among the 376 PCCs for which unenhanced attenuation data were available, 374 had an attenuation of >10 HU (99.5%). In the two exceptions (0.5%), unenhanced attenuation was exactly 10 HU, which lies just within the range of ≤10 HU that would suggest a diagnosis of ACA. Of 76 PCCs with unenhanced HU > 10 and available washout data, 22 (28.9%) had a high APW and/or RPW, suggestive of ACA. CONCLUSION: Based on the lack of PCCs with an unenhanced attenuation of <10 HU and the low proportion (0.5%) of PCCs with an attenuation of 10 HU, it seems reasonable to abstain from biochemical testing for PCC in AIs with an unenhanced attenuation of ≤10 HU. The assessment of contrast washout, however, is unreliable for ruling out PCC

Management of adrenal incidentalomas - a European Society of Endocrinology Clinical Practice Guideline in collaboration with the European Network for the Study of Adrenal Tumors

Diabetes mellitus: pathophysiological changes and therap

Efficacy and safety of once-monthly pasireotide in Cushing's disease: A 12 month clinical trial

© 2017 Elsevier Ltd. Background: Cushing's disease is a rare debilitating endocrine disorder for which few prospective interventional studies have been done. We report results of the first phase 3 trial assessing long-acting intramuscular pasireotide in patients with Cushing's disease. Methods: In this phase 3 clinical trial we recruited patients aged 18 years or older with persistent, recurrent, or de-novo (non-surgical candidates) Cushing's disease who had a mean urinary free cortisol (mUFC) concentration (from three 24 h samples) of 1·5-5·0 times the upper limit of normal (ULN), a normal or greater than normal morning plasma adrenocorticotropic hormone concentration, and a pituitary source of Cushing's syndrome, from 57 sites across 19 countries. Exclusion criteria included previous pasireotide treatment, mitotane therapy within 6 months, and pituitary irradiation within 10 years. We randomly allocated patients 1:1 (block size of four) using an interactive-response-technology system to intramuscular pasireotide 10 mg or 30 mg every 4 weeks for 12 months (in the core phase). We stratified randomisation by screening mUFC concentration (1·5 to < 2·0 × ULN and 2·0-5·0 × ULN). The dose could be uptitrated (from 10 mg to 30 mg or from 30 mg to 40 mg) at month 4 if the mUFC concentration was greater than 1·5 × ULN, and at month 7, month 9, or month 12 if the mUFC concentration was greater than 1·0 × ULN. Investigators, patients, site personnel, and those assessing outcomes were masked to dose group allocation. The primary endpoint was the proportion of patients in each group with an mUFC concentration of less than or equal to the ULN at month 7. Efficacy analyses were based on intention to treat. This trial is registered with ClinicalTrials.gov, number NCT01374906. Findings: Between Dec 28, 2011, and Dec 9, 2014, we randomly allocated 150 patients to receive pasireotide 10 mg (74 [49%] patients) or 30 mg (76 [51%] patients). The primary efficacy endpoint was met by 31 (41·9% [95% CI 30·5-53·9]) of 74 patients in the 10 mg group and 31 (40·8% [29·7-52·7] ) of 76 in the 30 mg group. The most common adverse events were hyperglycaemia (36 [49%] in the 10 mg group and 36 [47%] in the 30 mg group), diarrhoea (26 [35%] and 33 [43%] ), cholelithiasis (15 [20%] and 34 [45%] ), diabetes mellitus (14 [19%] and 18 [24%] ), and nausea (15 [20%] and 16 [21%] ). Serious adverse events suspected to be study drug related were reported in eight (11%) patients in the 10 mg group and four (5%) in the 30 mg group. Two (3%) patients in the 30 mg group died during the study (pulmonary artery thrombosis and cardiorespiratory failure); neither death was judged to be related to the study drug. Interpretation: Long-acting pasireotide normalised mUFC concentration in about 40% of patients with Cushing's disease at month 7 and had a similar safety profile to that of twice-daily subcutaneous pasireotide. Long-acting pasireotide is an efficacious treatment option for some patients with Cushing's disease who have persistent or recurrent disease after initial surgery or are not surgical candidates, and provides a convenient monthly administration schedule. Funding: Novartis Pharma AG