356 results on '"Martin NM"'
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202. Show Me Your Rump Hair and I Will Tell You What You Ate - The Dietary History of Muskoxen (Ovibos moschatus) Revealed by Sequential Stable Isotope Analysis of Guard Hairs.
- Author
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Mosbacher JB, Michelsen A, Stelvig M, Hendrichsen DK, and Schmidt NM
- Subjects
- Animals, Buttocks, Nitrogen Isotopes analysis, Seasons, Artiodactyla, Diet, Hair chemistry
- Abstract
The nutritional state of animals is tightly linked to the ambient environment, and for northern ungulates the state strongly influences vital population demographics, such as pregnancy rates. Continuously growing tissues, such as hair, can be viewed as dietary records of animals over longer temporal scales. Using sequential data on nitrogen stable isotopes (δ15N) in muskox guard hairs from ten individuals in high arctic Northeast Greenland, we were able to reconstruct the dietary history of muskoxen over approximately 2.5 years with a high temporal resolution of app. 9 days. The dietary chronology included almost three full summer and winter periods. The diet showed strong intra- and inter-annual seasonality, and was significantly linked to changes in local environmental conditions (temperature and snow depth). The summer diets were highly similar across years, reflecting a graminoid-dominated diet. In contrast, winter diets were markedly different between years, a pattern apparently linked to snow conditions. Snow-rich winters had markedly higher δ15N values than snow-poor winters, indicating that muskoxen had limited access to forage, and relied more heavily on their body stores. Due to the close link between body stores and calf production in northern ungulates, the dietary winter signals could eventually serve as an indicator of calf production the following spring. Our study opens the field for further studies and longer chronologies to test such links. The method of sequential stable isotope analysis of guard hairs thus constitutes a promising candidate for population-level monitoring of animals in remote, arctic areas.
- Published
- 2016
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203. Intravenous Immunoglobulin as an Immunomodulating Agent in Antineutrophil Cytoplasmic Antibody-Associated Vasculitides: A French Nationwide Study of Ninety-Two Patients.
- Author
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Crickx E, Machelart I, Lazaro E, Kahn JE, Cohen-Aubart F, Martin T, Mania A, Hatron PY, Hayem G, Blanchard-Delaunay C, de Moreuil C, Le Guenno G, Vandergheynst F, Maurier F, Crestani B, Dhote R, Silva NM, Ollivier Y, Mehdaoui A, Godeau B, Mariette X, Cadranel J, Cohen P, Puéchal X, Le Jeunne C, Mouthon L, Guillevin L, and Terrier B
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Antibodies, Antineutrophil Cytoplasmic blood, Churg-Strauss Syndrome drug therapy, Corticosterone administration & dosage, Female, Fluorescent Antibody Technique, Humans, Immune Tolerance, Immunoglobulins, Intravenous administration & dosage, Immunoglobulins, Intravenous adverse effects, Immunomodulation, Immunosuppressive Agents administration & dosage, Male, Microscopic Polyangiitis drug therapy, Middle Aged, Remission Induction, Retrospective Studies, Treatment Failure, Treatment Outcome, Young Adult, Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis drug therapy, Immunoglobulins, Intravenous pharmacology
- Abstract
Objective: Intravenous immunoglobulin (IVIG) represents a therapeutic alternative in antineutrophil cytoplasmic antibody-associated vasculitides (AAV), but its efficacy has been evaluated in only 2 small prospective trials. The aim of this study was to evaluate the efficacy and safety of IVIG in patients with AAV., Methods: We conducted a nationwide retrospective study of patients who received IVIG as immunomodulatory therapy for AAV., Results: A total of 92 patients (mean age 51 years) presenting with either granulomatosis with polyangiitis (Wegener's) (68%), eosinophilic granulomatosis with polyangiitis (Churg-Strauss) (22%), or microscopic polyangiitis (10%) received at least 1 course of IVIG. Antineutrophil cytoplasmic antibodies were present in 72% during the flare that required IVIG, as determined by immunofluorescence assay. IVIG was initiated because of relapsing disease in 83% of cases. IVIG was given for a median of 6 months (range 1-156 months) and in combination with corticosteroids in 21% of the patients or with other immunosuppressive agents in 77%. Efficacy of IVIG was assessed in the entire population and in a subset of 34 patients with unmodified background therapy. Remission rates at 6 months were 56% in the entire population and 58% in the unmodified background therapy group. Refractory disease and treatment failure at 6 months were observed in 7% and 18% in the whole population and 3% and 21% in the unmodified background therapy group, respectively. Adverse events (AEs) occurred in 33%, including serious AEs in 12% and AEs leading to discontinuation of IVIG in 7%., Conclusion: This large study shows the clinical benefit of IVIG as adjunctive therapy, with an acceptable tolerance profile, and thus supports its use in AAV patients with refractory or relapsing disease., (© 2016, American College of Rheumatology.)
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- 2016
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204. Preparation of legionaminic acid analogs of sialo-glycoconjugates by means of mammalian sialyltransferases.
- Author
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Watson DC, Wakarchuk WW, Gervais C, Durocher Y, Robotham A, Fernandes SM, Schnaar RL, Young NM, and Gilbert M
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- Animals, G(M1) Ganglioside chemistry, G(M1) Ganglioside metabolism, Humans, Interferon-alpha chemistry, Interferon-alpha metabolism, Myelin-Associated Glycoprotein chemistry, Myelin-Associated Glycoprotein metabolism, Protein Binding, Sialyltransferases metabolism, Swine, alpha 1-Antitrypsin chemistry, alpha 1-Antitrypsin metabolism, Sialic Acids chemistry, Sialyltransferases chemistry
- Abstract
Legionaminic acids are analogs of sialic acid that occur in several bacteria. The most commonly occurring form is Leg5Ac7Ac, which differs from Neu5Ac only at the C7 (acetamido) and C9 (deoxy) positions. While these differences greatly reduce the susceptibility of Leg compounds to sialidases, several sialyltransferases have been identified that can use CMP-Leg5Ac7Ac as a donor (Watson et al. 2011). We report the successful modification with Leg5Ac7Ac of a glycolipid, GM1a, and two glycoproteins, interferon-α2b and α1-antitrypsin, by means of two mammalian sialyltransferases, namely porcine ST3Gal1 and human ST6Gal1. The Leg5Ac7Ac form of GD1a was not recognized by the myelin-associated glycoprotein (MAG, Siglec-4), confirming the importance of the glycerol moiety in the interaction of sialo-glycans with Siglecs.
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- 2015
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205. Clinical outcomes in patients with nonfunctioning pituitary adenomas managed conservatively.
- Author
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Sam AH, Shah S, Saleh K, Joshi J, Roncaroli F, Robinson S, Cox J, Martin NM, Mendoza N, Meeran K, Mehta A, and Dhillo WS
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- Adult, Female, Humans, Male, Pituitary Gland pathology, Retrospective Studies, Watchful Waiting, Adenoma pathology, Pituitary Neoplasms pathology
- Abstract
Context: The natural history and the optimum management of patients with nonfunctioning pituitary adenomas (NFPAs) are unclear., Objective: Our objective was to characterize the natural history of patients with NFPAs managed conservatively., Design and Patients: We conducted a retrospective analysis of patients presenting to a tertiary referral centre between 1986 and 2009. Patients with pituitary adenomas and no clinical or biochemical evidence of hormonal hypersecretion were included. Those presenting with apoplexy or a radiological follow-up period of less than 1 year were excluded. The pituitary imaging for all patients was re-examined by two neuroradiologists in consensus., Outcome Measures: The outcome measures were change in tumour size and pituitary hormone function., Results: Sixty-six patients were managed conservatively for a mean follow-up period of 4·3 years (range: 1-14·7). Forty-seven (71%) had a macroadenoma, and nineteen (29%) had a microadenoma. Tumour size decreased or remained stable in 40% of macroadenomas and 47% of microadenomas. The median annual growth rate of enlarging macroadenomas and microadenomas was 1·0 mm/year and 0·4 mm/year, respectively. The median annual growth rate of macroadenomas was significantly higher than that of microadenomas (P < 0·01). Sixty-eight percentage of patients with a macroadenoma had pituitary hormone deficiency in one or more axes, compared to 42% of those with a microadenoma., Conclusion: Patients with NFPAs without optic chiasm compression can be managed conservatively. All patients need pituitary function assessment, irrespective of tumour size. These findings provide clinically relevant data for the management of patients with NFPAs., (© 2015 John Wiley & Sons Ltd.)
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- 2015
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206. Structure of the external aldimine form of PglE, an aminotransferase required for N,N'-diacetylbacillosamine biosynthesis.
- Author
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Riegert AS, Young NM, Watson DC, Thoden JB, and Holden HM
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- Acetylglucosamine biosynthesis, Acetylglucosamine chemistry, Campylobacter jejuni enzymology, Carbohydrate Sequence, Crystallography, X-Ray, Digitonin chemistry, Lysine chemistry, Semicarbazides chemistry, Valine chemistry, Acetylglucosamine analogs & derivatives, Campylobacter jejuni chemistry, Transaminases chemistry
- Abstract
N,N'-diacetylbacillosamine is a novel sugar that plays a key role in bacterial glycosylation. Three enzymes are required for its biosynthesis in Campylobacter jejuni starting from UDP-GlcNAc. The focus of this investigation, PglE, catalyzes the second step in the pathway. It is a PLP-dependent aminotransferase that converts UDP-2-acetamido-4-keto-2,4,6-trideoxy-d-glucose to UDP-2-acetamido-4-amino-2,4,6-trideoxy-d-glucose. For this investigation, the structure of PglE in complex with an external aldimine was determined to a nominal resolution of 2.0 Å. A comparison of its structure with those of other sugar aminotransferases reveals a remarkable difference in the manner by which PglE accommodates its nucleotide-linked sugar substrate., (© 2015 The Protein Society.)
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- 2015
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207. Sialyltransferases with enhanced legionaminic acid transferase activity for the preparation of analogs of sialoglycoconjugates.
- Author
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Watson DC, Wakarchuk WW, Leclerc S, Schur MJ, Schoenhofen IC, Young NM, and Gilbert M
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- Animals, Carbohydrate Conformation, Glycoconjugates chemistry, Models, Molecular, Mutation, Pasteurella multocida enzymology, Photobacterium enzymology, Swine, Glycoconjugates metabolism, N-Acetylneuraminic Acid metabolism, Sialic Acids metabolism, Sialyltransferases metabolism
- Abstract
Legionaminic acids (Leg) are bacterial analogs of neuraminic acid, with the same stereochemistry but different substituents at C5, C7 and C9. Hence they may be incorporated into useful analogs of sialoglycoconjugates, and we previously reported two sialyltransferases that could utilize cytidine monophosphate (CMP)-Leg5Ac7Ac for preparation of Leg glycoconjugates, which were resistant to sialidases [Watson DC, Leclerc S, Wakarchuk WW, Young NM. 2011. Enzymatic synthesis and properties of glycoconjugates with legionaminic acid as a replacement for neuraminic acid. Glycobiology. 21:99-108.]. These were the porcine ST3Gal1 and Pasteurella multocida sialyltransferases. We now report two additional sialyltransferases with superior Leg-transferase properties to the previous two. These are (i) a truncated form of a Photobacterium α2,6-sialyltransferase with an Ala-Met mutation in its active site, and (ii) an α2,3-sialyltransferase from Neisseria meningitidis MC58 with a higher transferase activity than the P. multocida enzyme, with either CMP-Neu5Ac or CMP-Leg5Ac7Ac as the donor. These enzymes will enable the production of useful Leg5Ac7Ac glycoconjugate derivatives with either α2,6 or α2,3 linkages and unique biological properties., (© Crown copyright 2015.)
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- 2015
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208. Draft Whole-Genome Sequence of Morganella morganii Serotype O:1ab.
- Author
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Nash JH and Young NM
- Abstract
Morganella morganii is a facultative pathogen of humans, causing urinary tract and postsurgical infections. Here, we report a high-quality draft assembly of the O:1ab serotype., (Copyright © 2015 Nash and Young.)
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- 2015
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209. Self-assessment of anatomy, sexual sensitivity, and function of the labia and vagina.
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Schober JM, Alguacil NM, Cooper RS, Pfaff DW, and Meyer-Bahlburg HF
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- Adult, Female, Humans, Middle Aged, Orgasm physiology, Plastic Surgery Procedures adverse effects, Risk Factors, Self Concept, Self Report, Sensation physiology, Sexual Behavior psychology, Vagina surgery, Vulva surgery, Self-Assessment, Sexual Behavior physiology, Vagina anatomy & histology, Vagina physiology, Vulva anatomy & histology, Vulva physiology
- Abstract
Patient perceptions of genital esthetics are motivating requests for plastic surgeries that could change sexual sensitivity. There is little information about the sensitivities of labial and introital sites. The aim of this study is to assess the relationship between sexual sensitivity and self-reported sizes of labial and introital sites. Sixty-two healthy, sexually active, adult women (mean age 37.9, range 21-60) with no history of genital or vaginal surgery gave written consent to participate in this study. A modified version of Self-Assessment of Genital Anatomy and Sexual Function (L-SAGASF-F) was used to assess labial and introital size. Site-specific sensation was rated on Likert scales of 1-5. Anatomical locations were compared for ratings. Of 62 responders, 84% (52) described their labia as "average-sized," 11% (7) described their labia minora and 13% (8) their labia majora as "large", and 3% (2) and 5% (3) as "small". Sexual pleasure ratings were "moderate" (median value: 3.0 for external genitalia and vaginal lumen) or "strong" (median value: 4.0 for the interior vagina). Significantly higher rankings related to the vaginal opening (P=0.007). Orgasm intensity for stimulation of the external genitalia progressively increased toward the vaginal opening, from 1.0 to 3.0 (P=0.001); vaginal ratings showed a similar progression, from 2.0 at the external luminal margin to 3.0 in the deep interior (P<0.0001). Orgasm effort scores were intermediate (median: 3.0), uniform throughout the external and internal areas (P=0.626). Ratings for labial and introital sensitivity, regardless of self-reported size, were very similar to those at other genital sites for sexual pleasure. Surgical excision of labial and introital structures could modify sexual sensation., (© 2015 Wiley Periodicals, Inc.)
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- 2015
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210. Diagnosis and treatment of unexplained anemia with iron deficiency without overt bleeding.
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Dahlerup JF, Eivindson M, Jacobsen BA, Jensen NM, Jørgensen SP, Laursen SB, Rasmussen M, and Nathan T
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- Biopsy, Needle, Denmark, Diagnosis, Differential, Female, Gastric Mucosa pathology, Gastrointestinal Hemorrhage therapy, Gastrointestinal Neoplasms therapy, Gastroscopy methods, Hematologic Tests, Humans, Immunohistochemistry, Male, Middle Aged, Prognosis, Risk Assessment, Severity of Illness Index, Treatment Outcome, Anemia, Iron-Deficiency diagnosis, Anemia, Iron-Deficiency drug therapy, Gastrointestinal Hemorrhage diagnosis, Gastrointestinal Neoplasms diagnosis, Iron Compounds therapeutic use, Practice Guidelines as Topic
- Abstract
A general overview is given of the causes of anemia with iron deficiency as well as the pathogenesis of anemia and the para-clinical diagnosis of anemia. Anemia with iron deficiency but without overt GI bleeding is associated with a risk of malignant disease of the gastrointestinal tract; upper gastrointestinal cancer is 1/7 as common as colon cancer. Benign gastrointestinal causes of anemia are iron malabsorption (atrophic gastritis, celiac disease, chronic inflammation, and bariatric surgery) and chronic blood loss due to gastrointestinal ulcerations. The following diagnostic strategy is recommended for unexplained anemia with iron deficiency: conduct serological celiac disease screening with transglutaminase antibody (IgA type) and IgA testing and perform bidirectional endoscopy (gastroscopy and colonoscopy). Bidirectional endoscopy is not required in premenopausal women < 40 years of age. Small intestine investigation (capsule endoscopy, CT, or MRI enterography) is not recommended routinely after negative bidirectional endoscopy but should be conducted if there are red flags indicating malignant or inflammatory small bowel disease (e.g., involuntary weight loss, abdominal pain or increased CRP). Targeted treatment of any cause of anemia with iron deficiency found on diagnostic assessment should be initiated. In addition, iron supplementation should be administered, with the goal of normalizing hemoglobin levels and replenishing iron stores. Oral treatment with a 100-200 mg daily dose of elemental iron is recommended (lower dose if side effects), but 3-6 months of oral iron therapy is often required to achieve therapeutic goals. Intravenous iron therapy is used if oral treatment lacks efficacy or causes side effects or in the presence of intestinal malabsorption or prolonged inflammation. Three algorithms are given for the following conditions: a) the paraclinical diagnosis of anemia with iron deficiency; b) the diagnostic work-up for unexplained anemia with iron deficiency without overt bleeding; and c) how to proceed after negative bidirectional endoscopy of the gastrointestinal tract.
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- 2015
211. Comparison of the utility of Cocaine- and Amphetamine-Regulated Transcript (CART), chromogranin A, and chromogranin B in neuroendocrine tumor diagnosis and assessment of disease progression.
- Author
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Ramachandran R, Bech P, Murphy KG, Caplin ME, Patel M, Vohra S, Khan MS, Dhillo WS, Sharma R, Palazzo FF, Win Z, Tan T, Khoo B, Meeran K, Frilling A, Ghatei MA, Bloom SR, and Martin NM
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- Adrenal Gland Neoplasms blood, Adult, Aged, Aged, 80 and over, Case-Control Studies, Diagnostic Techniques, Endocrine, Disease Progression, Female, Humans, Male, Middle Aged, Neuroendocrine Tumors blood, Paraganglioma blood, Pheochromocytoma blood, Predictive Value of Tests, Prognosis, Retrospective Studies, Young Adult, Cocaine- and Amphetamine-Regulated Transcript Protein, Adrenal Gland Neoplasms diagnosis, Biomarkers, Tumor blood, Chromogranin A blood, Chromogranin B blood, Nerve Tissue Proteins blood, Neuroendocrine Tumors diagnosis, Paraganglioma diagnosis, Pheochromocytoma diagnosis
- Abstract
Context: Prognosis in patients with neuroendocrine tumors (NETs) is often poor, frequently reflecting delayed diagnosis. Hence, accurate and practical NET markers are needed. Cocaine- and amphetamine-regulated transcript (CART) peptide is a potential novel NET marker., Design and Participants: Circulating levels of CART peptide and the established NET markers chromogranin A (CgA) and chromogranin B (CgB) were measured using RIA in 353 patients with NET (normal renal function) and in controls. Clinical data were collected retrospectively., Main Outcome Measure(s): The comparative and combined utility of CART, CgA, and CgB for diagnosis and assessment of disease progression was measured in different NET subtypes., Results: CgA and CgB in combination improved diagnostic accuracy in patients with gut NETs, nongastroenteropancreatic NETs, and NETs with an unknown primary origin compared with each biomarker alone. Measuring CART did not further improve diagnosis in these NET subtypes. For pancreatic NETs, CgB was superior to CgA and CART in detecting stable disease (P < .007), whereas CgA and CART in combination were most effective in identifying progressive disease. In phaeochromocytomas/paragangliomas (PCC/PGL), CART was the most useful biomarker for identifying stable (P < .001) and progressive (P = .001) disease. Consistent with this, plasma CART decreased following PCC/PGL tumor resection, remaining low in all patients in remission, but increasing in those with progressive disease., Conclusions: CART is a useful marker for identifying progressive pancreatic NETs. CART is superior to CgA and CgB in detecting stable and progressive PCC/PGLs, and may have a role as a surveillance marker for PCC/PGL patients.
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- 2015
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212. L-cysteine suppresses ghrelin and reduces appetite in rodents and humans.
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McGavigan AK, O'Hara HC, Amin A, Kinsey-Jones J, Spreckley E, Alamshah A, Agahi A, Banks K, France R, Hyberg G, Wong C, Bewick GA, Gardiner JV, Lehmann A, Martin NM, Ghatei MA, Bloom SR, and Murphy KG
- Subjects
- Adult, Animals, Appetite Depressants administration & dosage, Cysteine administration & dosage, Dose-Response Relationship, Drug, Female, Gastrointestinal Hormones metabolism, Ghrelin metabolism, Humans, Hypothalamus metabolism, Male, Mice, Mice, Inbred C57BL, RNA, Messenger, Rats, Rats, Wistar, Receptors, Gastrointestinal Hormone metabolism, Receptors, Neuropeptide metabolism, Satiation, Appetite drug effects, Appetite Depressants pharmacology, Cysteine pharmacology, Eating drug effects, Ghrelin antagonists & inhibitors
- Abstract
Background: High-protein diets promote weight loss and subsequent weight maintenance, but are difficult to adhere to. The mechanisms by which protein exerts these effects remain unclear. However, the amino acids produced by protein digestion may have a role in driving protein-induced satiety., Methods: We tested the effects of a range of amino acids on food intake in rodents and identified l-cysteine as the most anorexigenic. Using rodents we further studied the effect of l-cysteine on food intake, behaviour and energy expenditure. We proceeded to investigate its effect on neuronal activation in the hypothalamus and brainstem before investigating its effect on gastric emptying and gut hormone release. The effect of l-cysteine on appetite scores and gut hormone release was then investigated in humans., Results: l-Cysteine dose-dependently decreased food intake in both rats and mice following oral gavage and intraperitoneal administration. This effect did not appear to be secondary to behavioural or aversive side effects. l-Cysteine increased neuronal activation in the area postrema and delayed gastric emptying. It suppressed plasma acyl ghrelin levels and did not reduce food intake in transgenic ghrelin-overexpressing mice. Repeated l-cysteine administration decreased food intake in rats and obese mice. l-Cysteine reduced hunger and plasma acyl ghrelin levels in humans., Conclusions: Further work is required to determine the chronic effect of l-cysteine in rodents and humans on appetite and body weight, and whether l-cysteine contributes towards protein-induced satiety.
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- 2015
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213. Phylogenetic analysis of infectious pancreatic necrosis virus in Ireland reveals the spread of a virulent genogroup 5 subtype previously associated with imports.
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Ruane NM, McCleary SJ, McCarthy LJ, and Henshilwood K
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- Animals, Aquaculture, Birnaviridae Infections epidemiology, Birnaviridae Infections virology, Cluster Analysis, Fish Diseases virology, Genotype, Infectious pancreatic necrosis virus isolation & purification, Ireland epidemiology, Molecular Epidemiology, Molecular Sequence Data, Sequence Analysis, DNA, Sequence Homology, Birnaviridae Infections veterinary, Disease Outbreaks, Fish Diseases epidemiology, Infectious pancreatic necrosis virus classification, Infectious pancreatic necrosis virus genetics, Phylogeny, Salmo salar virology
- Abstract
Infectious pancreatic necrosis is a significant disease of farmed salmonids resulting in direct economic losses due to high mortality and disease-management costs. Significant outbreaks of the disease occurred in farmed Atlantic salmon in Ireland between 2003 and 2007, associated with imported ova and smolts. As the virus was known to occur in the country since the development of aquaculture in the 1980s, this study examined archived samples to determine whether these older isolates were associated with virulent forms. The study showed that two genotypes of IPNV were present in the 1990s, genotype 3 and genotype 5. A more virulent subtype of the virus first appeared in 2003 associated with clinical outbreaks of IPN, and this subtype is now the most prevalent form of IPNV found in the country. The data also indicated that IPNV in Ireland is more closely related to Scottish and continental European isolates than to Norwegian, Chilean and Australasian genogroup 5 isolates.
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- 2015
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214. Phenological mismatch with abiotic conditions implications for flowering in Arctic plants.
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Wheeler HC, Høye TT, Schmidt NM, Svenning JC, and Forchhammer MC
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- Arctic Regions, Environment, Ericaceae growth & development, Ericaceae physiology, Greenland, Magnoliopsida growth & development, Papaver growth & development, Papaver physiology, Reproduction, Rosaceae growth & development, Rosaceae physiology, Salix growth & development, Salix physiology, Seasons, Temperature, Climate Change, Flowers growth & development, Magnoliopsida physiology
- Abstract
Although many studies have examined the phenological mismatches between interacting organisms, few have addressed the potential for mismatches between phenology and seasonal weather conditions. In the Arctic, rapid phenological changes in many taxa are occurring in association with earlier snowmelt. The timing of snowmelt is jointly affected by the size of the late winter snowpack and the temperature during the spring thaw. Increased winter snowpack results in delayed snowmelt, whereas higher air temperatures and faster snowmelt advance the timing of snowmelt. Where interannual variation in snowpack is substantial, changes in the timing of snowmelt can be largely uncoupled from changes in air temperature. Using detailed, long-term data on the flowering phenology of four arctic plant species from Zackenberg, Greenland, we investigate whether there is a phenological component to the temperature conditions experienced prior to and during flowering. In particular, we assess the role of timing of flowering in determining pre-flowering exposure to freezing temperatures and to the temperatures-experienced prior to flowering. We then examine the implications of flowering phenology for flower abundance. Earlier snowmelt resulted in greater exposure to freezing conditions, suggesting an increased potential for a mismatch between the timing of flowering and seasonal weather conditions and an increased potential for negative consequences, such as freezing 'damage. We also found a parabolic relationship between the timing of flowering and the temperature experienced during flowering after taking interannual temperature effects into account. If timing of flowering advances to a cooler period of the growing season, this may moderate the effects of a general warming trend across years. Flower abundance was quadratically associated with the timing of flowering, such that both early and late flowering led to lower flower abundance than did intermediate flowering. Our results indicate that shifting the timing of flowering affects the temperature experienced during flower development and flowering beyond that imposed by interannual variations in climate. We also found that phenological timing may affect flower abundance, and hence, fitness. These findings suggest that plant population responses to future climate change will be shaped not only by extrinsic climate forcing, but also by species' phenological responses.
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- 2015
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215. Species-specific enzymatic tolerance of sulfide toxicity in plant roots.
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Martin NM and Maricle BR
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- Estuaries, Floods, Mitochondria drug effects, Oxidation-Reduction, Plant Proteins metabolism, Plant Roots enzymology, Species Specificity, Stress, Physiological, Sulfides metabolism, Water, Adaptation, Physiological, Alcohol Dehydrogenase metabolism, Ecosystem, Electron Transport Complex IV metabolism, Plant Roots drug effects, Plants drug effects, Plants enzymology, Plants genetics, Sulfides adverse effects
- Abstract
Toxic effects of sulfide come from a poisoning of a number of enzymes, especially cytochrome c oxidase, which catalyzes the terminal step in mitochondrial aerobic respiration. Despite this, some estuarine plants live in sulfide-rich sediments. We hypothesized estuarine and flooding-tolerant species might be more tolerant of sulfide compared to upland species, and this was tested by measures of root cytochrome c oxidase and alcohol dehydrogenase activities in extracts exposed to sulfide. Enzyme activities were measured in 0, 5, 10, 15, and 20 μM sodium sulfide, and compared among 17 species of plants. Activities of alcohol dehydrogenase and cytochrome c oxidase were both reduced by increasing sulfide concentration, but cytochrome c oxidase was more sensitive to sulfide compared to alcohol dehydrogenase. Activities of cytochrome c oxidase were reduced to near zero at 5-10 μM sulfide whereas alcohol dehydrogenase activities were only reduced by about 50% at 10 μM sulfide. All species were sensitive to increasing sulfide, but to different degrees. Cytochrome c oxidase in flooding-sensitive species was decreased to near zero activity at 5 μM sulfide, whereas activities in some flooding-tolerant species were still detectable until 15 μM sulfide. Cytochrome c oxidase activities in some estuarine species were low even in the absence of sulfide, perhaps an adaptation to avoid sulfide vulnerability in their native, sulfide-rich habitat. This illustrates the potent metabolic effects of sulfide, and this is the first demonstration of varying sensitivities of cytochrome c oxidase to sulfide across organisms, making these data of novel importance., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)
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- 2015
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216. [Certain opioids can preferably be administered transdermally].
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Jensen NM, Holmgaard R, Nielsen JB, and Sørensen JA
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- Acute Pain drug therapy, Administration, Cutaneous, Administration, Oral, Analgesics, Opioid adverse effects, Analgesics, Opioid pharmacology, Analgesics, Opioid therapeutic use, Anti-Inflammatory Agents, Non-Steroidal adverse effects, Anti-Inflammatory Agents, Non-Steroidal pharmacology, Anti-Inflammatory Agents, Non-Steroidal therapeutic use, Chronic Pain drug therapy, Denmark, Humans, Transdermal Patch, Analgesics, Opioid administration & dosage, Anti-Inflammatory Agents, Non-Steroidal administration & dosage
- Abstract
Many patients experience acute or chronic pain. The options for treating these pain conditions are many, and particularly products for topical application are gaining ground. NSAID for topical use is a good alternative to NSAID administered orally due to less systemic side effects. Transdermally delivered opioids have proven to be as effective as morphine in pain management of chronic, moderate to severe pain. The steady delivery and lower risk of breakthrough pain overweigh the higher cost and risk of adverse events compared to the orally delivered opioids.
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- 2015
217. Tumoral calcinosis during the course of systemic sclerosis.
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Audemard A, Silva NM, Boutemy J, Maigné G, and Bienvenu B
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- Calcinosis etiology, Female, Humans, Middle Aged, Radiography, Scleroderma, Systemic complications, Calcinosis diagnostic imaging, Hip Joint diagnostic imaging, Scleroderma, Systemic diagnostic imaging
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- 2015
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218. The structure of the Morganella morganii lipopolysaccharide core region and identification of its genomic loci.
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Vinogradov E, Nash JH, Foote S, and Young NM
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- Genomics, Genetic Loci, Genome, Plant genetics, Lipopolysaccharides chemistry, Lipopolysaccharides genetics, Morganella morganii genetics
- Abstract
The core region of the lipopolysaccharide of Morganella morganii serotype O:1ab was obtained by hydrolysis of the LPS and studied by 2D NMR, ESI MS, and chemical methods. Its structure was highly homologous to those from the two major members of the same Proteeae tribe, Proteus mirabilis and Providencia alcalifaciens, and analysis of the M. morganii genome disclosed that the loci for its outer core, lipid A and Ara4N moieties are similarly conserved., (Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.)
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- 2015
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219. The intrinsic cysteine and histidine residues of the anti-Salmonella antibody Se155-4: a model for the introduction of new functions into antibody-binding sites.
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Young NM, Watson DC, Cunningham AM, and MacKenzie CR
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- Antibodies, Bacterial genetics, Antibodies, Bacterial immunology, Copper chemistry, Copper metabolism, Cysteine, Enzyme-Linked Immunosorbent Assay, Escherichia coli, Fluorescent Dyes, Histidine, Hydrogen-Ion Concentration, Models, Molecular, Recombinant Proteins chemistry, Recombinant Proteins genetics, Recombinant Proteins immunology, Recombinant Proteins metabolism, Antibodies, Bacterial chemistry, Antibodies, Bacterial metabolism, Binding Sites, Antibody, Protein Engineering methods, Salmonella immunology
- Abstract
New functions can be incorporated into anti-hapten or anti-protein antibodies by mutating selected residues in the binding-site region either to Cys, to allow alkylation with reagents bearing the desired functional groups, or to His, to create metal-binding sites or to make antigen binding pH-sensitive. However, choosing suitable sites for these mutations has been hampered by the lack of antibodies with these features, to serve as models. Remarkably, the anti-carbohydrate antibody Se155-4, specific for the Salmonella group B lipopolysaccharide, already has a Cys and two pairs of His residues close to the antigen-binding pocket in its structure, and shows pH-dependent antigen binding. We therefore investigated modification of its Cys94L in an scFv version of the antibody with the aims of creating a 'reagentless' fluorescent sensor and attaching a metal-binding group that might confer lyase activity. These groups were successfully introduced, as judged by mass spectrometry, and had only slightly reduced antigen binding in enzyme-linked immunosorbent assay. The fluorescent product was sensitive to addition of antigen in a solution format, unlike a modification of a more distant Cys introduced into the VH CDR4 loop. Two other routes to modulate antigen binding were also explored, metal binding by the His pair alongside the antigen-binding pocket and insertions into CDR4 to extend the antigen-contact area. His residues adjacent to the antigen-binding pocket bound copper, causing a 5-fold decrease in antigen binding. In CDR4 of the VH domain, the preferred insert length was four residues, which gave stable antigen-binding products but did not improve overall antigen affinity., (© Crown copyright 2014.)
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- 2014
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220. Childhood mortality in federal medical centre umuahia, South eastern Nigeria.
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Charles NC, Chuku A, and Anazodo NM
- Abstract
Objectives: This study aimed to evaluate the mortality pattern in children seen at Federal Medical Centre Umuahia (FMCU) Abia state, South Eastern Nigeria., Methods: A retrospective cross sectional descriptive study over a 5-year period from January 1, 2004 to December 31, 2008 using data retrieved from the hospital's medical records department., Results: A total of 3,814 children were admitted in the hospital and 434 of them died giving a mortality rate of 11%. The mean age was 1.7 (Std D of 3.19). Two hundred and thirty eight of them were males while 196 of them were females giving a sex ratio of 1.2:1. Majority of the mortality (49%) occurred within 24 hours of admission. The major causes of death during neonatal period were birth asphyxia (34%), prematurity (24%) and neonatal sepsis (24%). Malaria was the leading cause of death beyond the neonatal period accounting for 42% of cases. Other common mortality causes were pneumonia, septicaemia, diarrhea, HIV AIDS and meningitis each accounting for 10%, 10%, 7%, 7% and 5% respectively. The months of July, May and March accounted for most deaths (12%, 12% and 11% respectively)., Conclusion: Birth asphyxia and malaria associated deaths were responsible for most deaths during neonatal and beyond neonatal periods respectively. Presence of trained personal at all deliveries will help to reduce neonatal asphyxia. Efforts should be made to reinforce the existing effective malaria control tools.
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- 2014
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221. Predicting the Origins of Anti-Blood Group Antibody Specificity: A Case Study of the ABO A- and B-Antigens.
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Makeneni S, Ji Y, Watson DC, Young NM, and Woods RJ
- Abstract
The ABO blood group system is the most important blood type system in human transfusion medicine. Here, we explore the specificity of antibody recognition toward ABO blood group antigens using computational modeling and biolayer interferometry. Automated docking and molecular dynamics simulations were used to explore the origin of the specificity of an anti-blood group A antibody variable fragment (Fv AC1001). The analysis predicts a number of Fv-antigen interactions that contribute to affinity, including a hydrogen bond between a His(L49) and the carbonyl moiety of the GalNAc in antigen A. This interaction was consistent with the dependence of affinity on pH, as measured experimentally; at lower pH there is an increase in binding affinity. Binding energy calculations provide unique insight into the origin of interaction energies at a per-residue level in both the scFv and the trisaccharide antigen. The calculations indicate that while the antibody can accommodate both blood group A and B antigens in its combining site, the A antigen is preferred by 4 kcal/mol, consistent with the lack of binding observed for the B antigen.
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- 2014
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222. Effects of non-local exchange on core level shifts for gas-phase and adsorbed molecules.
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Van den Bossche M, Martin NM, Gustafson J, Hakanoglu C, Weaver JF, Lundgren E, and Grönbeck H
- Abstract
Density functional theory calculations are often used to interpret experimental shifts in core level binding energies. Calculations based on gradient-corrected (GC) exchange-correlation functionals are known to reproduce measured core level shifts (CLS) of isolated molecules and metal surfaces with reasonable accuracy. In the present study, we discuss a series of examples where the shifts calculated within a GC-functional significantly deviate from the experimental values, namely the CLS of C 1s in ethyl trifluoroacetate, Pd 3d in PdO and the O 1s shift for CO adsorbed on PdO(101). The deviations are traced to effects of the electronic self-interaction error with GC-functionals and substantially better agreements between calculated and measured CLS are obtained when a fraction of exact exchange is used in the exchange-correlation functional.
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- 2014
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223. Neuroimaging, behavioral, and psychological sequelae of repetitive combined blast/impact mild traumatic brain injury in Iraq and Afghanistan war veterans.
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Petrie EC, Cross DJ, Yarnykh VL, Richards T, Martin NM, Pagulayan K, Hoff D, Hart K, Mayer C, Tarabochia M, Raskind MA, Minoshima S, and Peskind ER
- Subjects
- Adult, Afghan Campaign 2001-, Anisotropy, Blast Injuries pathology, Blast Injuries psychology, Brain Injuries pathology, Brain Injuries psychology, Female, Humans, Iraq War, 2003-2011, Male, Mental Disorders pathology, Mental Disorders psychology, Middle Aged, Nerve Fibers, Myelinated pathology, Neuroimaging, Neuropsychological Tests, Stress Disorders, Post-Traumatic pathology, Stress Disorders, Post-Traumatic psychology, Young Adult, Blast Injuries complications, Brain Injuries complications, Mental Disorders etiology, Stress Disorders, Post-Traumatic etiology, Veterans psychology
- Abstract
Abstract Whether persisting cognitive complaints and postconcussive symptoms (PCS) reported by Iraq and Afghanistan war veterans with blast- and/or combined blast/impact-related mild traumatic brain injuries (mTBIs) are associated with enduring structural and/or functional brain abnormalities versus comorbid depression or posttraumatic stress disorder (PTSD) remains unclear. We sought to characterize relationships among these variables in a convenience sample of Iraq and Afghanistan-deployed veterans with (n=34) and without (n=18) a history of one or more combined blast/impact-related mTBIs. Participants underwent magnetic resonance imaging of fractional anisotropy (FA) and macromolecular proton fraction (MPF) to assess brain white matter (WM) integrity; [(18)F]-fluorodeoxyglucose positron emission tomography imaging of cerebral glucose metabolism (CMRglu); structured clinical assessments of blast exposure, psychiatric diagnoses, and PTSD symptoms; neurologic evaluations; and self-report scales of PCS, combat exposure, depression, sleep quality, and alcohol use. Veterans with versus without blast/impact-mTBIs exhibited reduced FA in the corpus callosum; reduced MPF values in subgyral, longitudinal, and cortical/subcortical WM tracts and gray matter (GM)/WM border regions (with a possible threshold effect beginning at 20 blast-mTBIs); reduced CMRglu in parietal, somatosensory, and visual cortices; and higher scores on measures of PCS, PTSD, combat exposure, depression, sleep disturbance, and alcohol use. Neuroimaging metrics did not differ between participants with versus without PTSD. Iraq and Afghanistan veterans with one or more blast-related mTBIs exhibit abnormalities of brain WM structural integrity and macromolecular organization and CMRglu that are not related to comorbid PTSD. These findings are congruent with recent neuropathological evidence of chronic brain injury in this cohort of veterans.
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- 2014
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224. A high pressure x-ray photoelectron spectroscopy study of CO oxidation over Rh(100).
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Gustafson J, Blomberg S, Martin NM, Fernandes V, Borg A, Liu Z, Chang R, and Lundgren E
- Abstract
We have studied the oxidation of CO over Rh(100) using high pressure x-ray photoelectron spectroscopy under CO and O2 pressures ranging from 0.01 to 1 mbar. The results show a very low or no conversion for the CO covered surface found at low temperatures, while the activity rises slightly when the temperature is high enough for some CO to desorb, exposing surface sites for dissociative O2 adsorption. As the temperature is increased further, more CO desorbs and oxygen replaces CO as the dominating species at the surface. At the same time we find a sudden increase in the reactivity, such that all CO that reaches the surface is instantly transformed into CO2. We find that the O coverage in the active state is highly dependent on the total pressure and, although we do not detect any presence of a surface oxide as in previous surface x-ray diffraction studies, the highest O coverage indicates that the surface is close to being oxidized.
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- 2014
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225. The biochemical utility of chromogranin A, chromogranin B and cocaine- and amphetamine-regulated transcript for neuroendocrine neoplasia.
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Bech PR, Martin NM, Ramachandran R, and Bloom SR
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- Biomarkers, Tumor genetics, Humans, Neuroendocrine Tumors diagnosis, Neuroendocrine Tumors pathology, Pancreas metabolism, Pancreas pathology, Prognosis, Somatostatin metabolism, Cocaine- and Amphetamine-Regulated Transcript Protein, Chromogranin A genetics, Chromogranin B genetics, Nerve Tissue Proteins genetics, Neuroendocrine Tumors genetics
- Abstract
Neuroendocrine neoplasia (NEN) is a heterogeneous group of tumours and often represents a therapeutic challenge to clinicians. The peptides chromogranin A (CgA), chromogranin B (CgB) and cocaine- and amphetamine-regulated transcript (CART) are widely distributed throughout the neuroendocrine system. CgA and CgB have been used as general NEN biomarkers for many years, while CART has only recently been identified. Of these biomarkers, CgA is the most commonly used. However, circulating CgA concentrations exhibit considerable intra-individual biological variation, are altered by proton pump inhibitors (PPIs) and somatostatin analogues and are elevated in non-NEN malignancies. Therefore, interpretation of CgA results must be in the context of these confounding factors. The effects of treatment and non-NEN conditions on circulating CgB and CART concentrations are less well understood. CgB is less affected by impaired renal function and PPIs than CgA; while, circulating CART concentrations lack a diurnal variation in humans and are more reliable markers of pancreatic NEN malignancy than CgA. The utility of circulating CgA measurements in NEN prognosis, surveillance and disease recurrence has been widely investigated. However, the utility of CgB and CART in NEN management is yet to be elucidated. Further studies are needed to establish whether CgB and CART are useful alternatives to CgA.
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- 2014
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226. Coronary vasculitis associated with T-cell prolymphocytic leukemia.
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Audemard A, Boutemy J, Guilpain P, Sabatier R, Silva NM, and Bienvenu B
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- Alemtuzumab, Antibodies, Monoclonal, Humanized therapeutic use, Antineoplastic Agents therapeutic use, Coronary Angiography, Coronary Artery Disease diagnostic imaging, Coronary Artery Disease drug therapy, Humans, Leukemia, Prolymphocytic, T-Cell drug therapy, Male, Middle Aged, Vasculitis diagnostic imaging, Vasculitis drug therapy, Coronary Artery Disease etiology, Leukemia, Prolymphocytic, T-Cell complications, Vasculitis etiology
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- 2014
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227. Review of phosphocholine substituents on bacterial pathogen glycans: synthesis, structures and interactions with host proteins.
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Young NM, Foote SJ, and Wakarchuk WW
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- C-Reactive Protein metabolism, Host-Pathogen Interactions immunology, Humans, Molecular Structure, Phosphorylcholine chemistry, Phosphorylcholine metabolism, Pneumococcal Infections metabolism, Pneumococcal Infections microbiology, Polysaccharides chemistry, Polysaccharides metabolism, Protein Binding immunology, Streptococcus pneumoniae metabolism, Streptococcus pneumoniae physiology, C-Reactive Protein immunology, Phosphorylcholine immunology, Pneumococcal Infections immunology, Polysaccharides immunology, Streptococcus pneumoniae immunology
- Abstract
Among the non-carbohydrate components of glycans, the addition of phosphocholine (ChoP) to the glycans of pathogens occurs more rarely than acetylation or methylation, but it has far more potent biological consequences. These arise from ChoP's multiple interactions with host proteins, which are important at all stages of the infection process. These stages include initial adherence to cells, encountering the host's innate immune system and then the adaptive immune system. Thus, in the initial stages of an infection, ChoP groups are an asset to the pathogen, but they can turn into a disadvantage subsequently. In this review, we have focussed on structural aspects of these phenomena. We describe the biosynthesis of the ChoP modification, the structures of the pathogen glycans known to carry ChoP groups and the host proteins that recognize ChoP., (Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.)
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- 2013
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228. Clinical images: Bronchial stenosis in granulomatosis with polyangiitis (Wegener's).
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Audemard A, Bienvenu B, Magnier R, Fournier L, Galateau-Salle F, and Silva NM
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- Adult, Bronchial Diseases complications, Bronchial Diseases pathology, Constriction, Pathologic complications, Constriction, Pathologic diagnostic imaging, Constriction, Pathologic pathology, Female, Granulomatosis with Polyangiitis complications, Granulomatosis with Polyangiitis pathology, Humans, Radiography, Bronchial Diseases diagnostic imaging, Granulomatosis with Polyangiitis diagnostic imaging
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- 2013
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229. Hepcidin levels in diabetes mellitus and polycystic ovary syndrome.
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Sam AH, Busbridge M, Amin A, Webber L, White D, Franks S, Martin NM, Sleeth M, Ismail NA, Daud NM, Papamargaritis D, Le Roux CW, Chapman RS, Frost G, Bloom SR, and Murphy KG
- Subjects
- Adult, Blood Glucose metabolism, Female, Ferritins deficiency, Hepcidins deficiency, Homeostasis, Humans, Intercellular Signaling Peptides and Proteins metabolism, Male, Middle Aged, Diabetes Mellitus, Type 1 blood, Diabetes Mellitus, Type 2 blood, Ferritins blood, Hepcidins blood, Insulin Resistance, Polycystic Ovary Syndrome blood
- Abstract
Aim: Increased body iron is associated with insulin resistance. Hepcidin is the key hormone that negatively regulates iron homeostasis. We hypothesized that individuals with insulin resistance have inadequate hepcidin levels for their iron load., Methods: Serum concentrations of the active form of hepcidin (hepcidin-25) and hepcidin:ferritin ratio were evaluated in participants with Type 2 diabetes (n = 33, control subjects matched for age, gender and BMI, n = 33) and participants with polycystic ovary syndrome (n = 27, control subjects matched for age and BMI, n = 16). To investigate whether any changes observed were associated with insulin resistance rather than insulin deficiency or hyperglycaemia per se, the same measurements were made in participants with Type 1 diabetes (n = 28, control subjects matched for age, gender and BMI, n = 30). Finally, the relationship between homeostasis model assessment of insulin resistance and serum hepcidin:ferritin ratio was explored in overweight or obese participants without diabetes (n = 16)., Results: Participants with Type 2 diabetes had significantly lower hepcidin and hepcidin:ferritin ratio than control subjects (P < 0.05 and P < 0.01, respectively). Participants with polycystic ovary syndrome had a significantly lower hepcidin:ferritin ratio than control subjects (P < 0.05). There was no significant difference in hepcidin or hepcidin:ferritin ratio between participants with Type 1 diabetes and control subjects (P = 0.88 and P = 0.94). Serum hepcidin:ferritin ratio inversely correlated with homeostasis model assessment of insulin resistance (r = -0.59, P < 0.05)., Conclusion: Insulin resistance, but not insulin deficiency or hyperglycaemia per se, is associated with inadequate hepcidin levels. Reduced hepcidin concentrations may cause increased body iron stores in insulin-resistant states., (© 2013 The Authors. Diabetic Medicine published by John Wiley & Sons Ltd on behalf of Diabetes UK.)
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- 2013
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230. Glucagon and GLP-1 inhibit food intake and increase c-fos expression in similar appetite regulating centres in the brainstem and amygdala.
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Parker JA, McCullough KA, Field BC, Minnion JS, Martin NM, Ghatei MA, and Bloom SR
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- Animals, Appetite drug effects, Dose-Response Relationship, Drug, Eating drug effects, Energy Metabolism, Glucagon pharmacology, Glucagon-Like Peptide 1 pharmacology, Injections, Intraperitoneal, Male, Mice, Proto-Oncogene Proteins c-fos drug effects, Amygdala metabolism, Appetite physiology, Brain Stem metabolism, Glucagon metabolism, Glucagon-Like Peptide 1 metabolism, Proto-Oncogene Proteins c-fos metabolism
- Abstract
Background: Glucagon and glucagon-like peptide-1 (GLP-1) are evolutionarily related anorectic hormones. Glucagon also increases energy expenditure. The combination of glucagon and GLP-1 could cause weight loss through a simultaneous reduction in food intake and increased energy expenditure. However, the effect of combined administration of glucagon and GLP-1 on food intake and neuronal activation has not previously been studied. Furthermore, the effect of glucagon on neuronal activation in appetite regulating centres has not been assessed. Characterisation of the effects of glucagon when administered singly and in combination with GLP-1 on neuronal activation will be important for determining the mechanism of action of related potential antiobesity therapies., Objectives: To investigate the effects of peripherally administered GLP-1 and glucagon on food intake, neuronal activation and blood glucose in mice when administered individually and in combination., Methodology: Food intake, blood glucose and c-fos expression in the hypothalamus, amygdala and brainstem were measured in response to GLP-1 and glucagon, alone and in combination., Results: Peripherally administered GLP-1 and glucagon decreased food intake and increased c-fos expression in the brainstem and amygdala. Doses of GLP-1 and glucagon that individually did not significantly affect feeding, in combination were anorectic and stimulated neuronal activation in the area postrema (AP) and central nucleus of the amygdala. Combined administration of GLP-1 and glucagon prevented the acute hyperglycemic effect of glucagon alone., Conclusion: Anorectic doses of glucagon and GLP-1 induced similar patterns of c-fos expression. Combined administration of low dose GLP-1 and glucagon inhibited food intake and induced c-fos expression in the AP and amygdala. The combination of both hormones may offer the opportunity to utilise the beneficial effects of reduced food intake and increased energy expenditure, and may therefore be a potential treatment for obesity.
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- 2013
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231. Deubiquitylating enzymes and DNA damage response pathways.
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Jacq X, Kemp M, Martin NM, and Jackson SP
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- Humans, Neoplasms metabolism, Neoplasms pathology, Oxidative Stress, Tumor Suppressor Protein p53 metabolism, Ubiquitin Thiolesterase metabolism, DNA Damage, DNA Repair, Ubiquitin-Specific Proteases metabolism
- Abstract
Covalent post-translational modification of proteins by ubiquitin and ubiquitin-like factors has emerged as a general mechanism to regulate myriad intra-cellular processes. The addition and removal of ubiquitin or ubiquitin-like proteins from factors has recently been demonstrated as a key mechanism to modulate DNA damage response (DDR) pathways. It is thus, timely to evaluate the potential for ubiquitin pathway enzymes as DDR drug targets for therapeutic intervention. The synthetic lethal approach provides exciting opportunities for the development of targeted therapies to treat cancer: most tumours have lost critical DDR pathways, and thus rely more heavily on the remaining pathways, while normal tissues are still equipped with all DDR pathways. Here, we review key deubiquitylating enzymes (DUBs) involved in DDR pathways, and describe how targeting DUBs may lead to selective therapies to treat cancer patients.
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- 2013
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232. Rehabilitation for cirrhotic patients discharged after hepatic encephalopathy improves survival.
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Andersen MM, Aunt S, Jensen NM, Homann C, Manniche J, Svendsen S, Christensen E, Reher-Langberg A, and Schiødt FV
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- Adult, Aged, Alcohol Drinking prevention & control, End Stage Liver Disease mortality, End Stage Liver Disease rehabilitation, Female, Hepatic Encephalopathy etiology, Humans, Liver Cirrhosis, Alcoholic complications, Male, Middle Aged, Patient Readmission economics, Severity of Illness Index, Social Work, Survival Rate, Ambulatory Care, Hepatic Encephalopathy mortality, Hepatic Encephalopathy rehabilitation, Liver Cirrhosis, Alcoholic mortality, Liver Cirrhosis, Alcoholic rehabilitation
- Abstract
Introduction: The 1-year mortality of cirrhotic patients with hepatic encephalopathy (HE) is approximately 60-80% in recent studies. We aimed to establish a rehabilitation out-patient clinic (RC) for alcoholic cirrhotic patients sur-viving HE., Material and Methods: Prospectively, patients surviving HE were offered participation in the RC and were seen by a nurse for a one-hour interview with 1-3 weeks' interval after discharge and by a physician, if needed. Clinical, psychological and social problems were identified and addressed. Alcohol consumption was recorded and alcohol cessation was encouraged at each visit. Minimal or overt HE prompted referral to the Liver Unit. The patients were compared with HE patients discharged in 2008 (the control group)., Results: A total of 19 patients were included in the RC group and compared with the 14 patients of the control group. The Child-Pugh score was higher in the RC group (median 13; range 8-14) than in the control group (median 11; range 7-13) (p = 0.033), whereas other clinical, demographic and biochemical parameters did not differ between the two groups. One-year survival was higher in the RC group (16/19; 84%) than in the control group versus (5/14; 36%) (p = 0.012). The log-rank test confirmed an improved survival for the RC group (p = 0.008). The economic costs of subsequent hospital admissions did not differ between the two groups. In the RC group, alcohol consumption was reduced in all but two patients., Conclusion: Survival was significantly improved for patients in the rehabilitation clinic. The improved survival did not subsequently cause higher hospital admission costs., Funding: not relevant., Trial Registration: not relevant.
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- 2013
233. Metabolic stress regulates cytoskeletal dynamics and metastasis of cancer cells.
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Caino MC, Chae YC, Vaira V, Ferrero S, Nosotti M, Martin NM, Weeraratna A, O'Connell M, Jernigan D, Fatatis A, Languino LR, Bosari S, and Altieri DC
- Subjects
- Adenylate Kinase metabolism, Animals, Antineoplastic Agents pharmacology, Autophagy-Related Protein-1 Homolog, Bone Neoplasms secondary, Carcinoma, Non-Small-Cell Lung mortality, Carcinoma, Non-Small-Cell Lung secondary, Cell Line, Tumor, Cell Movement, Female, Gene Knockdown Techniques, Guanidines pharmacology, HSP90 Heat-Shock Proteins genetics, HSP90 Heat-Shock Proteins metabolism, Hexokinase metabolism, Humans, Intracellular Signaling Peptides and Proteins genetics, Intracellular Signaling Peptides and Proteins metabolism, Kaplan-Meier Estimate, Lactams, Macrocyclic pharmacology, Liver Neoplasms, Experimental secondary, Lung Neoplasms mortality, Lung Neoplasms pathology, Mice, Mice, SCID, Mitochondria metabolism, Mitochondrial Membranes enzymology, NIH 3T3 Cells, Neoplasm Transplantation, Phosphorylation, Protein Processing, Post-Translational, Protein Serine-Threonine Kinases genetics, Protein Serine-Threonine Kinases metabolism, RNA, Small Interfering genetics, Bone Neoplasms metabolism, Carcinoma, Non-Small-Cell Lung metabolism, Cytoskeleton metabolism, Liver Neoplasms, Experimental metabolism, Lung Neoplasms metabolism, Stress, Physiological
- Abstract
Metabolic reprogramming is an important driver of tumor progression; however, the metabolic regulators of tumor cell motility and metastasis are not understood. Here, we show that tumors maintain energy production under nutrient deprivation through the function of HSP90 chaperones compartmentalized in mitochondria. Using cancer cell lines, we found that mitochondrial HSP90 proteins, including tumor necrosis factor receptor-associated protein-1 (TRAP-1), dampen the activation of the nutrient-sensing AMPK and its substrate UNC-51-like kinase (ULK1), preserve cytoskeletal dynamics, and release the cell motility effector focal adhesion kinase (FAK) from inhibition by the autophagy initiator FIP200. In turn, this results in enhanced tumor cell invasion in low nutrients and metastatic dissemination to bone or liver in disease models in mice. Moreover, we found that phosphorylated ULK1 levels were correlated with shortened overall survival in patients with non-small cell lung cancer. These results demonstrate that mitochondrial HSP90 chaperones, including TRAP-1, overcome metabolic stress and promote tumor cell metastasis by limiting the activation of the nutrient sensor AMPK and preventing autophagy.
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- 2013
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234. Preclinical evaluation of a novel ATM inhibitor, KU59403, in vitro and in vivo in p53 functional and dysfunctional models of human cancer.
- Author
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Batey MA, Zhao Y, Kyle S, Richardson C, Slade A, Martin NM, Lau A, Newell DR, and Curtin NJ
- Subjects
- Animals, Ataxia Telangiectasia Mutated Proteins antagonists & inhibitors, Camptothecin administration & dosage, Clinical Trials as Topic, DNA-Binding Proteins, Doxorubicin administration & dosage, Drug Evaluation, Preclinical, Drug Resistance, Neoplasm drug effects, Etoposide administration & dosage, Gene Expression Regulation, Neoplastic drug effects, HCT116 Cells, Humans, Mice, Neoplasms metabolism, Neoplasms pathology, Xenograft Model Antitumor Assays, Ataxia Telangiectasia Mutated Proteins metabolism, Heterocyclic Compounds, 3-Ring administration & dosage, Neoplasms drug therapy, Pyrones administration & dosage, Radiation-Sensitizing Agents administration & dosage, Tumor Suppressor Protein p53 metabolism
- Abstract
Ataxia telangiectasia mutated (ATM) kinase signals DNA double-strand breaks (DSB) to cell-cycle arrest via p53 and DNA repair. ATM-defective cells are sensitive to DSB-inducing agents, making ATM an attractive target for anticancer chemo- and radiosensitization. KU59403 is an ATM inhibitor with the potency, selectivity, and solubility for advanced preclinical evaluation. KU59403 was not cytotoxic to human cancer cell lines (SW620, LoVo, HCT116, and MDA-MB-231) per se but significantly increased the cytotoxicity of topoisomerase I and II poisons: camptothecin, etoposide, and doxorubicin. Chemo- and radiosensitization by ATM inhibition was not p53-dependent. Following administration to mice, KU59403 distributed to tissues and concentrations exceeding those required for in vitro activity were maintained for at least 4 hours in tumor xenografts. KU59403 significantly enhanced the antitumor activity of topoisomerase poisons in mice bearing human colon cancer xenografts (SW620 and HCT116) at doses that were nontoxic alone and well-tolerated in combination. Chemosensitization was both dose- and schedule-dependent. KU59403 represents a major advance in ATM inhibitor development, being the first compound to show good tissue distribution and significant chemosensitization in in vivo models of human cancer, without major toxicity. KU59403 provides the first proof-of-principle preclinical data to support the future clinical development of ATM inhibitors., (©2013 AACR)
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- 2013
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235. Trans-equatorial migration routes, staging sites and wintering areas of a high-Arctic avian predator: the long-tailed Skua (Stercorarius longicaudus).
- Author
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Gilg O, Moe B, Hanssen SA, Schmidt NM, Sittler B, Hansen J, Reneerkens J, Sabard B, Chastel O, Moreau J, Phillips RA, Oudman T, Biersma EM, Fenstad AA, Lang J, and Bollache L
- Subjects
- Animals, Arctic Regions, Breeding, Greenland, Svalbard, Time Factors, Animal Migration physiology, Birds physiology, Predatory Behavior physiology, Seasons
- Abstract
The Long-tailed Skua, a small (<300 g) Arctic-breeding predator and seabird, is a functionally very important component of the Arctic vertebrate communities in summer, but little is known about its migration and winter distribution. We used light-level geolocators to track the annual movements of eight adult birds breeding in north-east Greenland (n = 3) and Svalbard (n = 5). All birds wintered in the Southern Hemisphere (mean arrival-departure dates on wintering grounds: 24 October-21 March): five along the south-west coast of Africa (0-40°S, 0-15°E), in the productive Benguela upwelling, and three further south (30-40°S, 0-50°E), in an area extending into the south-west Indian Ocean. Different migratory routes and rates of travel were documented during post-breeding (345 km d(-1) in late August-early September) and spring migrations (235 km d(-1) in late April) when most birds used a more westerly flyway. Among the different staging areas, a large region off the Grand Banks of Newfoundland appears to be the most important. It was used in autumn by all but one of the tracked birds (from a few days to three weeks) and in spring by five out of eight birds (from one to more than six weeks). Two other staging sites, off the Iberian coast and near the Azores, were used by two birds in spring for five to six weeks. Over one year, individuals travelled between 43,900 and 54,200 km (36,600-45,700 when excluding staging periods) and went as far as 10,500-13,700 km (mean 12,800 km) from their breeding sites. This study has revealed important marine areas in both the south and north Atlantic Ocean. Sustainable management of these ocean basins will benefit Long-tailed Skuas as well as other trans-equatorial migrants from the Arctic.
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- 2013
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236. Comparison of the overnight metyrapone and glucagon stimulation tests in the assessment of secondary hypoadrenalism.
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Cegla J, Jones B, Seyani L, Papadoulou D, Wynne K, Martin NM, Meeran K, Chapman R, Donaldson M, Goldstone AP, and Tan T
- Subjects
- Adult, Female, Humans, Hypothalamo-Hypophyseal System drug effects, Male, Middle Aged, Pituitary-Adrenal System drug effects, Prospective Studies, Adrenal Insufficiency diagnosis, Glucagon pharmacology, Metyrapone pharmacology
- Abstract
Objective: The insulin tolerance test (ITT) is contraindicated in a proportion of patients with suspected ACTH deficiency. The aim of this study was to investigate the diagnostic accuracy of the glucagon stress test (GST) compared with the overnight metyrapone test (OMT) in patients with contraindications to ITT., Design: This was a prospective comparison of the GST to the OMT in patients with suspected ACTH deficiency and contraindications to the ITT. The OMT was used as the standard for comparison. The study was conducted at two tertiary referral centres for pituitary disease., Patients: Seventy-eight patients underwent contemporaneous OMT and GST of whom 61 had sufficient suppression of cortisol during the OMT to be included in the comparison. Forty had suffered traumatic brain injury, 36 had organic pituitary disorders and two were classified as 'other'., Measurements: ACTH sufficiency was defined as 0800h 11-deoxycortisol ≥ 200 nmol/l on OMT and peak cortisol ≥ 440 nmol/l on GST, as per local reference ranges., Results: There was significant discrepancy between the proportion of patients diagnosed with ACTH deficiency using the OMT (39%) and GST (89%). From our data, a GST peak cortisol cut-off of ≥350 nm provides the combination of optimal sensitivity (71%) and specificity (57%), compared with a higher sensitivity (88%) but poor specificity (11%) using a cut-off of ≥440 nm., Conclusions: The GST should be used with caution as a diagnostic test of ACTH reserve. The OMT should be used in preference to the GST to assess the hypothalamic pituitary adrenal axis where ITT is contraindicated., (© 2012 Blackwell Publishing Ltd.)
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- 2013
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237. Regulation of lung cancer metastasis by Klf4-Numb-like signaling.
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Vaira V, Faversani A, Martin NM, Garlick DS, Ferrero S, Nosotti M, Kissil JL, Bosari S, and Altieri DC
- Subjects
- Animals, Base Sequence, Cell Line, Tumor, Cell Movement genetics, Cluster Analysis, Disease Progression, Female, Gene Expression Profiling, Humans, Intracellular Signaling Peptides and Proteins metabolism, Kruppel-Like Factor 4, Kruppel-Like Transcription Factors metabolism, Lung Neoplasms metabolism, Mice, MicroRNAs chemistry, MicroRNAs genetics, Neoplasm Metastasis, Neoplastic Stem Cells metabolism, RNA Interference, Transcription, Genetic, Gene Expression Regulation, Neoplastic, Intracellular Signaling Peptides and Proteins genetics, Kruppel-Like Transcription Factors genetics, Lung Neoplasms genetics, Lung Neoplasms pathology, Signal Transduction
- Abstract
Metastatic traits seem to be acquired by transformed cells with progenitor-like cancer-initiating properties, but there remains little mechanistic insight into this linkage. In this report, we show that the polarity protein Numbl, which is expressed normally in neuronal progenitors, becomes overexpressed and mislocalized in cancer cells from a variety of human tumors. Numbl overexpression relies on loss of the tumor suppressor miRNA-296-5p (miR-296), which actively represses translation of Numbl in normal cells. In turn, deregulated expression of Numbl mediates random tumor cell migration and invasion, blocking anoikis and promoting metastatic dissemination. In clinical specimens of non-small cell lung cancer, we found that Numbl overexpression correlated with a reduction in overall patient survival. Mechanistically, Numbl-mediated tumorigenesis involved suppression of a "stemness" transcriptional program driven by the stem cell programming transcription factor Klf4, thereby preserving a pool of progenitor-like cells in lung cancer. Our results reveal that Numbl-Klf4 signaling is critical to maintain multiple nodes of metastatic progression, including persistence of cancer-initiating cells, rationalizing its therapeutic exploitation to improve the treatment of advanced lung cancer., (©2013 AACR.)
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- 2013
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238. In situ x-ray photoelectron spectroscopy of model catalysts: at the edge of the gap.
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Blomberg S, Hoffmann MJ, Gustafson J, Martin NM, Fernandes VR, Borg A, Liu Z, Chang R, Matera S, Reuter K, and Lundgren E
- Abstract
We present high-pressure x-ray photoelectron spectroscopy (HP-XPS) and first-principles kinetic Monte Carlo study addressing the nature of the active surface in CO oxidation over Pd(100). Simultaneously measuring the chemical composition at the surface and in the near-surface gas phase, we reveal both O-covered pristine Pd(100) and a surface oxide as stable, highly active phases in the near-ambient regime accessible to HP-XPS. Surprisingly, no adsorbed CO can be detected during high CO(2) production rates, which can be explained by a combination of a remarkably short residence time of the CO molecule on the surface and mass-transfer limitations in the present setup.
- Published
- 2013
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239. Optimization of potent and selective dual mTORC1 and mTORC2 inhibitors: the discovery of AZD8055 and AZD2014.
- Author
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Pike KG, Malagu K, Hummersone MG, Menear KA, Duggan HM, Gomez S, Martin NM, Ruston L, Pass SL, and Pass M
- Subjects
- Benzamides, Cell Growth Processes drug effects, Cells, Cultured, Hepatocytes drug effects, Hepatocytes enzymology, Hepatocytes metabolism, Humans, Mechanistic Target of Rapamycin Complex 1, Mechanistic Target of Rapamycin Complex 2, Pyrimidines, Morpholines pharmacology, Multiprotein Complexes antagonists & inhibitors, Protein Kinase Inhibitors pharmacology, TOR Serine-Threonine Kinases antagonists & inhibitors
- Abstract
The optimization of a potent and highly selective series of dual mTORC1 and mTORC2 inhibitors is described. An initial focus on improving cellular potency whilst maintaining or improving other key parameters, such as aqueous solubility and margins over hERG IC(50), led to the discovery of the clinical candidate AZD8055 (14). Further optimization, particularly aimed at reducing the rate of metabolism in human hepatocyte incubations, resulted in the discovery of the clinical candidate AZD2014 (21)., (Copyright © 2013 Elsevier Ltd. All rights reserved.)
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- 2013
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240. Cyclophilin D extramitochondrial signaling controls cell cycle progression and chemokine-directed cell motility.
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Tavecchio M, Lisanti S, Lam A, Ghosh JC, Martin NM, O'Connell M, Weeraratna AT, Kossenkov AV, Showe LC, and Altieri DC
- Subjects
- Animals, Apoptosis, Cell Cycle, Cell Line, Tumor, Cell Lineage, Cell Movement, Cell Proliferation, Cell Survival, Peptidyl-Prolyl Isomerase F, Gene Expression Profiling, Gene Expression Regulation, Gene Expression Regulation, Neoplastic, Humans, Mice, NIH 3T3 Cells, RNA, Small Interfering metabolism, STAT3 Transcription Factor metabolism, Signal Transduction, Chemokines metabolism, Cyclophilins metabolism, Mitochondria metabolism
- Abstract
Mitochondria control bioenergetics and cell fate decisions, but how they influence nuclear gene expression is understood poorly. Here, we show that deletion or reduction in the levels of cyclophilin D (CypD, also called Ppif), a mitochondrial matrix peptidyl prolyl isomerase and apoptosis regulator, results in increased cell proliferation and enhanced cell migration and invasion. These responses are associated with extensive transcriptional changes, modulation of a chemokine/chemokine receptor gene signature, and activation of the pleiotropic inflammatory mediator, STAT3. In the absence of CypD, active STAT3 enhances cell proliferation via accelerated entry into S-phase and stimulates autocrine/paracrine cell motility through Cxcl12-Cxcr4-directed chemotaxis. Therefore, CypD directs mitochondria-to-nuclei inflammatory gene expression in normal and tumor cells. This pathway may contribute to malignant traits under conditions of CypD modulation.
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- 2013
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241. Skin closure after trauma laparotomy in high-risk patients: opening opportunities for improvement.
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Seamon MJ, Smith BP, Capano-Wehrle L, Fakhro A, Fox N, Goldberg M, Martin NM, Pathak AS, and Ross SE
- Subjects
- Abdominal Injuries surgery, Adult, Female, Humans, Laparotomy adverse effects, Male, Retrospective Studies, Risk Factors, Surgical Wound Dehiscence prevention & control, Young Adult, Laparotomy methods, Surgical Wound Infection prevention & control
- Abstract
Background: Although many surgeons leave laparotomy incisions open after colon injury to prevent surgical site infection (SSI), other injured patient subsets are also at risk. We hypothesized that leaving trauma laparotomy skin incisions open in high-risk patients with any enteric injury or requiring damage control laparotomy (DCL) would not affect superficial SSI and fascial dehiscence rates., Methods: Patients who underwent trauma laparotomy (2004-2008) at two Level I centers were reviewed. To ensure a high-risk sample, only patients with transmural enteric injuries or need for DCL surviving 5 days or more were included. SSIs were categorized by the CDC (Centers for Disease Control and Prevention) criteria and risk factors were analyzed by skin closure (open vs. any closure). Significant (p < 0.05) univariate variables were applied to two multivariate analyses examining superficial SSI and fascial dehiscence., Results: Of 1,501 patients who underwent laparotomy, 503 met inclusion criteria. Patients were young (median, 28.0 years; range, 22.0-40.0 years) with penetrating (74%) or enteric (80%) injuries, and DCL (36%) and SSI (44%; superficial, 25%; deep, 3%; organ/space, 25%) were common. While no difference in superficial SSI after loose (n = 136) or complete skin closure (n = 224) was detected (p = 0.64), superficial SSIs were less common with open skin incisions (9.8%), despite multiple risk factors, than with any skin closure (31.1%, p < 0.001). Predictors of superficial SSIs and fascial dehiscence were each evaluated with multiple-variable logistic regression analysis. After adjusting for multiple potential confounding variables, any skin closure increased the risk of superficial SSIs approximately nine times (odds ratio, 8.6; p < 0.001) and fascial dehiscence six times (odds ratio, 5.7; p = 0.013)., Conclusion: Management of skin incisions takes careful consideration like any other step of a laparotomy. Our results suggest that the decision to leave skin open is one simple method to improve outcomes in high-risk patients., Level of Evidence: Therapeutic study, level III.
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- 2013
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242. Associations of angiotensin targeting antihypertensive drugs with mortality and hospitalization in primary care patients with dementia.
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Kehoe PG, Davies NM, Martin RM, and Ben-Shlomo Y
- Subjects
- Aged, Aged, 80 and over, Angiotensin Receptor Antagonists administration & dosage, Angiotensin-Converting Enzyme Inhibitors administration & dosage, Antihypertensive Agents administration & dosage, Antihypertensive Agents adverse effects, Cohort Studies, Dementia drug therapy, Drug Delivery Systems trends, Female, Follow-Up Studies, Humans, Longitudinal Studies, Male, Primary Health Care trends, Angiotensin Receptor Antagonists adverse effects, Angiotensin-Converting Enzyme Inhibitors adverse effects, Dementia mortality, Drug Delivery Systems methods, Hospitalization trends, Primary Health Care methods
- Abstract
We investigated whether angiotensin II receptor blockers and angiotensin converting enzyme inhibitors were associated with risk of mortality or inpatient hospitalization for patients with dementia compared to other antihypertensive medications. We extracted a clinical cohort of 6,290 patients with dementia from the United Kingdom General Practice Research Database, prescribed antihypertensive medication at diagnosis of dementia with around 10 years follow-up. Using survival analysis we estimated associations of exposure to antihypertensive medication with subsequent hospitalization and mortality risk, stratified by dementia type (Alzheimer's disease, vascular and other dementias). Angiotensin converting enzyme inhibitors (but not angiotensin II receptor blockers) were associated with an increased risk of mortality in patients with Alzheimer's disease (adjusted hazard ratio: 1.19; 95% CI 1.07, 1.33, p = 0.002), but no convincing evidence of increased hospitalization. Angiotensin II receptor blockers were inversely associated with hospitalization for any form of dementia, but after adjustment for covariates, these associations became consistent with chance. Further evidence is required to either support or refute the observation that exposure to angiotensin converting enzyme inhibitors in patients with dementia is associated with increased mortality.
- Published
- 2013
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243. Loss of 53BP1 causes PARP inhibitor resistance in Brca1-mutated mouse mammary tumors.
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Jaspers JE, Kersbergen A, Boon U, Sol W, van Deemter L, Zander SA, Drost R, Wientjens E, Ji J, Aly A, Doroshow JH, Cranston A, Martin NM, Lau A, O'Connor MJ, Ganesan S, Borst P, Jonkers J, and Rottenberg S
- Subjects
- ATP Binding Cassette Transporter, Subfamily B, Member 1 deficiency, Animals, BRCA1 Protein genetics, Cell Line, Tumor, DNA Damage, Female, Mammary Neoplasms, Animal drug therapy, Mice, Mutation, Tumor Suppressor p53-Binding Protein 1, Antineoplastic Agents therapeutic use, Chromosomal Proteins, Non-Histone genetics, DNA-Binding Proteins genetics, Drug Resistance, Neoplasm, Enzyme Inhibitors therapeutic use, Phthalazines therapeutic use, Piperazines therapeutic use, Piperidines therapeutic use, Poly(ADP-ribose) Polymerase Inhibitors
- Abstract
Unlabelled: Inhibition of PARP is a promising therapeutic strategy for homologous recombination-deficient tumors, such as BRCA1-associated cancers. We previously reported that BRCA1-deficient mouse mammary tumors may acquire resistance to the clinical PARP inhibitor (PARPi) olaparib through activation of the P-glycoprotein drug efflux transporter. Here, we show that tumor-specific genetic inactivation of P-glycoprotein increases the long-term response of BRCA1-deficient mouse mammary tumors to olaparib, but these tumors eventually developed PARPi resistance. In a fraction of cases, this resistance is caused by partial restoration of homologous recombination due to somatic loss of 53BP1. Importantly, PARPi resistance was minimized by long-term treatment with the novel PARP inhibitor AZD2461, which is a poor P-glycoprotein substrate. Together, our data suggest that restoration of homologous recombination is an important mechanism for PARPi resistance in BRCA1-deficient mammary tumors and that the risk of relapse of BRCA1-deficient tumors can be effectively minimized by using optimized PARP inhibitors., Significance: In this study, we show that loss of 53BP1 causes resistance to PARP inhibition in mouse mammary tumors that are deficient in BRCA1. We hypothesize that low expression or absence of 53BP1 also reduces the response of patients with BRCA1-deficient tumors to PARP inhibitors.
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- 2013
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244. Adjuvant lithium improves the efficacy of radioactive iodine treatment in Graves' and toxic nodular disease.
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Martin NM, Patel M, Nijher GM, Misra S, Murphy E, and Meeran K
- Subjects
- Adult, Female, Humans, Hyperthyroidism radiotherapy, Male, Middle Aged, Retrospective Studies, Graves Disease radiotherapy, Iodine Radioisotopes therapeutic use, Lithium therapeutic use
- Abstract
Context: Lithium increases iodine retention in the thyroid gland and inhibits thyroid hormone release. Although lithium has been reported to improve the efficacy of radioactive iodine (RAI) treatment in Graves' disease, its role as an adjunct to RAI treatment of hyperthyroidism, particularly in toxic nodular disease, remains contentious., Objective: To assess whether adjuvant lithium increases the efficacy of a fixed dose RAI regimen in Graves' and toxic nodular hyperthyroid patients., Design and Setting: Retrospective cohort study in a tertiary referral centre. Two hundred and four hyperthyroid patients (163 Graves' disease, 26 toxic multinodular goitre and 15 solitary toxic thyroid adenoma)., Intervention: One hundred and three patients received RAI alone (median dose 558 MBq). One hundred and one patients received RAI (median dose 571 MBq) with adjuvant lithium (800 mg/day for 10 days)., Main Outcome Measure: Proportion of patients cured at any time over a 1-year period following RAI treatment. Cure was defined as sustained (two or more sequential time points) biochemical euthyroidism or hypothyroidism during the follow-up period., Results: The likelihood of cure at any time was 60% greater in all hyperthyroid patients (Graves' plus toxic nodular disease) receiving adjuvant lithium (n = 204, P = 0·003). In patients with Graves' disease receiving RAI + lithium, there was a similar occurrence in cure (n = 163, P = 0·006). Cure was twice as likely in patients with toxic nodular (non-Graves') disease receiving RAI + lithium compared with RAI alone (n = 41, P = 0·01)., Conclusions: This study supports the use of adjuvant lithium to improve the efficacy of RAI in the treatment of Grave's disease and suggests a novel role in the management of toxic nodular (non-Graves') disease., (© 2012 Blackwell Publishing Ltd.)
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- 2012
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245. Chemosensitization of cancer cells by KU-0060648, a dual inhibitor of DNA-PK and PI-3K.
- Author
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Munck JM, Batey MA, Zhao Y, Jenkins H, Richardson CJ, Cano C, Tavecchio M, Barbeau J, Bardos J, Cornell L, Griffin RJ, Menear K, Slade A, Thommes P, Martin NM, Newell DR, Smith GC, and Curtin NJ
- Subjects
- Animals, Antineoplastic Agents administration & dosage, Antineoplastic Agents pharmacokinetics, Cell Line, Tumor, Chromones administration & dosage, Drug Resistance, Neoplasm, Enzyme Activation, Enzyme Inhibitors administration & dosage, Enzyme Inhibitors pharmacokinetics, Female, Humans, MCF-7 Cells, Mice, Neoplasms drug therapy, Neoplasms metabolism, Thiophenes administration & dosage, Tumor Burden drug effects, Xenograft Model Antitumor Assays, Antineoplastic Agents pharmacology, Chromones pharmacology, DNA-Activated Protein Kinase antagonists & inhibitors, Enzyme Inhibitors pharmacology, Phosphoinositide-3 Kinase Inhibitors, Thiophenes pharmacology
- Abstract
DNA double-strand breaks (DSB) are the most cytotoxic lesions induced by topoisomerase II poisons. Nonhomologous end joining (NHEJ) is a major pathway for DSB repair and requires DNA-dependent protein kinase (DNA-PK) activity. DNA-PK catalytic subunit (DNA-PKcs) is structurally similar to PI-3K, which promotes cell survival and proliferation and is upregulated in many cancers. KU-0060648 is a dual inhibitor of DNA-PK and PI-3K in vitro. KU-0060648 was investigated in a panel of human breast and colon cancer cells. The compound inhibited cellular DNA-PK autophosphorylation with IC(50) values of 0.019 μmol/L (MCF7 cells) and 0.17 μmol/L (SW620 cells), and PI-3K-mediated AKT phosphorylation with IC(50) values of 0.039 μmol/L (MCF7 cells) and more than 10 μmol/L (SW620 cells). Five-day exposure to 1 μmol/L KU-0060648 inhibited cell proliferation by more than 95% in MCF7 cells but only by 55% in SW620 cells. In clonogenic survival assays, KU-0060648 increased the cytotoxicity of etoposide and doxorubicin across the panel of DNA-PKcs-proficient cells, but not in DNA-PKcs-deficient cells, thus confirming that enhanced cytotoxicity was due to DNA-PK inhibition. In mice bearing SW620 and MCF7 xenografts, concentrations of KU-0060648 that were sufficient for in vitro growth inhibition and chemosensitization were maintained within the tumor for at least 4 hours at nontoxic doses. KU-0060648 alone delayed the growth of MCF7 xenografts and increased etoposide-induced tumor growth delay in both in SW620 and MCF7 xenografts by up to 4.5-fold, without exacerbating etoposide toxicity to unacceptable levels. The proof-of-principle in vitro and in vivo chemosensitization with KU-0060648 justifies further evaluation of dual DNA-PK and PI-3K inhibitors.
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- 2012
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246. A comparison of the performance of ⁶⁸Ga-DOTATATE PET/CT and ¹²³I-MIBG SPECT in the diagnosis and follow-up of phaeochromocytoma and paraganglioma.
- Author
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Maurice JB, Troke R, Win Z, Ramachandran R, Al-Nahhas A, Naji M, Dhillo W, Meeran K, Goldstone AP, Martin NM, Todd JF, Palazzo F, and Tan T
- Subjects
- Adolescent, Adult, Follow-Up Studies, Humans, Middle Aged, Retrospective Studies, Sensitivity and Specificity, Young Adult, 3-Iodobenzylguanidine, Adrenal Gland Neoplasms diagnostic imaging, Multimodal Imaging methods, Organometallic Compounds, Paraganglioma diagnostic imaging, Pheochromocytoma diagnostic imaging, Positron-Emission Tomography, Tomography, Emission-Computed, Single-Photon methods, Tomography, X-Ray Computed
- Abstract
Purpose: To compare the sensitivity of (123)I-metaiodobenzylguanidine (MIBG) SPECT and (68)Ga-DOTATATE PET/CT in detecting phaeochromocytomas (PCC) and paragangliomas (PGL) in the initial diagnosis and follow-up of patients with PCC and PGL disease., Methods: Retrospective analysis of 15 patients with PCC/PGL who had contemporaneous (123)I-MIBG and (68)Ga-DOTATATE imaging., Results: Of the 15 patients in the series, 8 were concordant with both modalities picking up clinically significant lesions. There were no patients in whom both modalities failed to pick up clinically significant lesions. There was discordance in seven patients: 5 had positive (68)Ga-DOTATATE and negative (123)I-MIBG, and 2 (12 and 14) had negative (68)Ga-DOTATATE and positive (123)I-MIBG. Utilizing (123)I-MIBG as the gold standard, (68)Ga-DOTATATE had a sensitivity of 80 % and a positive predictive value of 62 %. The greatest discordance was in head and neck lesions, with the lesions in 4 patients being picked up by (68)Ga-DOTATATE and missed by (123)I-MIBG. On a per-lesion analysis, cross-sectional (CT and MRI) and (68)Ga-DOTATATE was superior to (123)I-MIBG in detecting lesions in all anatomical locations, and particularly bony lesions., Conclusion: First, (68)Ga-DOTATATE should be considered as a first-line investigation in patients at high risk of PGL and metastatic disease, such as in the screening of carriers for mutations associated with familial PGL syndromes. Second, if (123)I-MIBG does not detect lesions in patients with a high pretest probability of PCC or PGL, (68)Ga-DOTATATE should be considered as the next investigation. Third, (68)Ga-DOTATATE hould be considered in preference to (123)I-MIBG in patients in whom metastatic spread, particularly to the bone, is suspected.
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- 2012
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247. Improved diagnostic accuracy for neuroendocrine neoplasms using two chromogranin A assays.
- Author
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Ramachandran R, Bech P, Murphy KG, Dhillo WS, Meeran KM, Chapman RS, Caplin M, Ghatei MA, Bloom SR, and Martin NM
- Subjects
- Adult, Aged, Aged, 80 and over, Biomarkers, Tumor blood, Chromogranin A blood, Female, Humans, Logistic Models, Male, Middle Aged, Neuroendocrine Tumors blood, Young Adult, Biomarkers, Tumor analysis, Chromogranin A analysis, Neuroendocrine Tumors diagnosis, Radioimmunoassay methods
- Abstract
Context: Chromogranin A (Cg A) is the best available diagnostic marker for neuroendocrine neoplasms (NENs). However, clinical interpretation of Cg A results may be limited by considerable heterogeneity between commonly available Cg A assays. Variation in diagnostic accuracy of these assays largely reflects differences in antibody specificities. We compared the diagnostic utility of four Cg A assays [Imperial Supra-regional Assay Service radioimmunoassay (SAS) and three commercial assays, Cisbio, DAKO and Eurodiagnostica]., Method: Plasma Cg A was measured using these four assays in 125 patients with NENs, 41 patients with cancers other than NENs and 108 healthy controls., Result: There was no significant difference in diagnostic accuracy between any of the four assays alone and no single assay positively identified all patients with NEN. However, concordance between assays was variable. Cisbio and SAS assays were least concordant. We, therefore, hypothesized that using a combination of the least concordant Cg A assays will improve NEN diagnosis by detecting a larger number of Cg A epitopes and hence patients with NEN. Consistent with our hypothesis, multiple logistic regression analysis showed that the combination of Cisbio and SAS assays was more useful than any other combinations or any assay alone in predicting a NEN diagnosis., Conclusion: Although individually, all four Cg A assays are similarly useful for the measurement of Cg A in the diagnosis of a NEN, in patients with a suspected NEN, negative results by one assay should prompt analysis by a second assay. The combination of Cisbio and SAS assays may have greatest diagnostic utility., (© 2011 Blackwell Publishing Ltd.)
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- 2012
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248. Quantifying the effects of renal impairment on plasma concentrations of the neuroendocrine neoplasia biomarkers chromogranin A, chromogranin B, and cocaine- and amphetamine-regulated transcript.
- Author
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Bech PR, Ramachandran R, Dhillo WS, Martin NM, and Bloom SR
- Subjects
- Case-Control Studies, Glomerular Filtration Rate, Humans, Neuroendocrine Tumors diagnosis, Renal Insufficiency blood, Renal Insufficiency physiopathology, Renal Insufficiency, Chronic physiopathology, Sensitivity and Specificity, Cocaine- and Amphetamine-Regulated Transcript Protein, Biomarkers, Tumor blood, Chromogranin A blood, Chromogranin B blood, Nerve Tissue Proteins blood, Neuroendocrine Tumors blood, Renal Insufficiency, Chronic blood
- Published
- 2012
- Full Text
- View/download PDF
249. Effective combination treatment with cabergoline and low-dose pegvisomant in active acromegaly: a prospective clinical trial.
- Author
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Higham CE, Atkinson AB, Aylwin S, Bidlingmaier M, Drake WM, Lewis A, Martin NM, Moyes V, Newell-Price J, and Trainer PJ
- Subjects
- Acromegaly blood, Adult, Aged, Aged, 80 and over, Cabergoline, Dopamine Agonists administration & dosage, Dopamine Agonists adverse effects, Drug Monitoring, Drug Resistance drug effects, Drug Therapy, Combination adverse effects, Ergolines administration & dosage, Ergolines adverse effects, Female, Human Growth Hormone administration & dosage, Human Growth Hormone adverse effects, Human Growth Hormone blood, Human Growth Hormone therapeutic use, Humans, Insulin-Like Growth Factor I analysis, Male, Middle Aged, Patient Dropouts, United Kingdom, Acromegaly drug therapy, Dopamine Agonists therapeutic use, Ergolines therapeutic use, Human Growth Hormone analogs & derivatives, Receptors, Somatotropin antagonists & inhibitors
- Abstract
Context: With adequate dose titration, pegvisomant normalizes IGF-I in up to 97% of patients with acromegaly. Pegvisomant is indicated for treatment-resistant disease but is expensive, particularly at a high dose. It has been used successfully in combination with somatostatin analogs. However, there are no therapeutic reports of pegvisomant in combination with dopamine agonists. Cabergoline is orally active, well-tolerated, and relatively inexpensive, and as monotherapy for acromegaly it is reported to normalize IGF-I in up to 30% of patients., Objective: The aim of the study was to investigate the efficacy of cabergoline monotherapy and pegvisomant in combination with cabergoline to control serum IGF-I in patients with active acromegaly. Twenty-four patients were recruited into a United Kingdom, multicenter, open-label, prospective clinical trial., Main Outcome Measure: We measured the change in serum IGF-I., Results: After 18 wk of dose titration to a maximum dose of 0.5 mg once daily, cabergoline monotherapy did not significantly reduce IGF-I (454 ± 219 baseline vs. 389 ± 192 ng/ml cabergoline), although two patients did normalize IGF-I. The addition of 10 mg pegvisomant daily for 12 wk significantly reduced IGF-I (389 ± 192 ng/ml cabergoline vs. 229 ± 101 ng/ml combination), and 68% achieved a normal IGF-I. Twelve weeks after cabergoline withdrawal, while continuing to receive pegvisomant 10 mg, only 26% of patients maintained an IGF-I within the reference range (229 ± 101 ng/ml combination vs. 305 ± 177 ng/ml pegvisomant). There were no significant changes in liver transaminases or glucose metabolism throughout the study., Conclusion: These data suggest that combination treatment with cabergoline and pegvisomant is more effective at reducing IGF-I levels than either cabergoline or pegvisomant monotherapy.
- Published
- 2012
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250. The Active Phase of Palladium during Methane Oxidation.
- Author
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Hellman A, Resta A, Martin NM, Gustafson J, Trinchero A, Carlsson PA, Balmes O, Felici R, van Rijn R, Frenken JW, Andersen JN, Lundgren E, and Grönbeck H
- Abstract
The active phase of Pd during methane oxidation is a long-standing puzzle, which, if solved, could provide routes for design of improved catalysts. Here, density functional theory and in situ surface X-ray diffraction are used to identify and characterize atomic sites yielding high methane conversion. Calculations are performed for methane dissociation over a range of Pd and PdOx surfaces and reveal facile dissociation on either under-coordinated Pd sites in PdO(101) or metallic surfaces. The experiments show unambiguously that high methane conversion requires sufficiently thick PdO(101) films or metallic Pd, in full agreement with the calculations. The established link between high activity and atomic structure enables rational design of improved catalysts.
- Published
- 2012
- Full Text
- View/download PDF
Catalog
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