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1.
Eur Phys J C Part Fields ; 82(10): 930, 2022.
Article in English | MEDLINE | ID: mdl-36277417

ABSTRACT

Fast interpolation-grid frameworks facilitate an efficient and flexible evaluation of higher-order predictions for any choice of parton distribution functions or value of the strong coupling α s . They constitute an essential tool for the extraction of parton distribution functions and Standard Model parameters, as well as studies of the dependence of cross sections on the renormalisation and factorisation scales. The APPLfast project provides a generic interface between the parton-level Monte Carlo generator and both the APPLgrid and the fastNLO libraries for the grid interpolation. The extension of the project to include hadron-hadron collider processes at next-to-next-to-leading order in perturbative QCD is presented, together with an application for jet production at the LHC.

2.
Eur Phys J C Part Fields ; 79(10): 845, 2019.
Article in English | MEDLINE | ID: mdl-31807114

ABSTRACT

The extension of interpolation-grid frameworks for perturbative QCD calculations at next-to-next-to-leading order (NNLO) is presented for deep inelastic scattering (DIS) processes. A fast and flexible evaluation of higher-order predictions for any a posteriori choice of parton distribution functions (PDFs) or value of the strong coupling constant is essential in iterative fitting procedures to extract PDFs and Standard Model parameters as well as for a detailed study of the scale dependence. The APPLfast project, described here, provides a generic interface between the parton-level Monte Carlo program NNLOjet and both the APPLgrid and fastNLO libraries for the production of interpolation grids at NNLO accuracy. Details of the interface for DIS processes are presented together with the required interpolation grids at NNLO, which are made available. They cover numerous inclusive jet measurements by the H1 and ZEUS experiments at HERA. An extraction of the strong coupling constant is performed as an application of the use of such grids and a best-fit value of α s ( M Z ) = 0.1170 ( 15 ) exp ( 25 ) th is obtained using the HERA inclusive jet cross section data.

3.
J Pharmacol Toxicol Methods ; 62(1): 12-9, 2010.
Article in English | MEDLINE | ID: mdl-20570743

ABSTRACT

INTRODUCTION: ICH S7A and S7B guidelines recommend the use of conscious animals for assessment of non-clinical cardiovascular safety of new chemical entities prior to testing in humans. Protocol design and data analysis techniques can affect the quality of the data produced and can therefore ultimately influence the clinical management of cardiovascular risk. It is therefore essential to have an understanding of the magnitude of changes detectable and the clinical relevance of these changes. This paper describes the utilisation of "super-intervals" to analyse and interpret data obtained from our conscious telemetered dog cardiovascular safety protocol and reports the statistical power achieved to detect changes in various cardiovascular parameters. METHODS: Cardiovascular data from 18 dog telemetry studies were used to calculate the statistical power to detect changes in cardiovascular parameters. Each study followed a test compound versus vehicle cross-over experimental design with 24h monitoring (n=4). 1 min mean raw data from each individual animal was compressed into 15 min mean data for each dose group for visualisation. Larger summary periods, or "super-intervals", were then selected to best represent any observed cardiovascular effects whilst taking into account the pharmacokinetic profile of the drug e.g. intervals of 1 to 6, 7 to 14 and 14 to 22h post-dose. RESULTS: With this methodology and study design we predict, using the median percentile that our studies have 80% power to detect the following changes: HR (+/-10bpm), LV +dP/dt max (+/-375mmHg/s), MBP (+/-5mmHg) and QTc (+/-4ms). DISCUSSION: Super-intervals are a simple way to handle the high degree of natural variability seen with any ambulatory cardiovascular assessment and, in our hands, result in highly statistically powered studies. The ability of this model to detect cardiovascular changes of small, but biologically relevant, magnitude enables confident decision making around the cardiovascular safety of new chemical entities.


Subject(s)
Anti-Infective Agents/pharmacology , Antihypertensive Agents/pharmacology , Aza Compounds/pharmacology , Cardiovascular System/drug effects , Doxazosin/pharmacology , Electrocardiography/drug effects , Quinolines/pharmacology , Animals , Anti-Infective Agents/administration & dosage , Anti-Infective Agents/blood , Antihypertensive Agents/administration & dosage , Antihypertensive Agents/blood , Aza Compounds/administration & dosage , Aza Compounds/blood , Blood Pressure/drug effects , Consciousness , Data Interpretation, Statistical , Dogs , Dose-Response Relationship, Drug , Doxazosin/administration & dosage , Doxazosin/blood , Drug Evaluation, Preclinical , Fluoroquinolones , Heart Rate/drug effects , Long QT Syndrome/diagnosis , Male , Models, Animal , Models, Statistical , Moxifloxacin , Quinolines/administration & dosage , Quinolines/blood , Telemetry , Time Factors
5.
Cardiovasc Drugs Ther ; 3(4): 545-55, 1989 Aug.
Article in English | MEDLINE | ID: mdl-2577312

ABSTRACT

The hemodynamic actions of the new dihydropyridine calcium-channel blocker amlodipine were assessed and compared with those of nitrendipine using anesthetised dogs and were also investigated in conscious dogs with and without beta-adrenergic blockade. After bolus intravenous administration, amlodipine (25 to 1600 micrograms/kg) or nitrendipine (1 to 128 micrograms/kg) was administered to anesthetised dogs at 30-minute intervals, caused dose-related reductions in systemic and coronary vascular resistances with corresponding increases in cardiac output and coronary flow. Nitrendipine, unlike amlodipine, caused marked acute hypotension. The onset of action of amlodipine was markedly slower than that of nitrendipine, and effects were maintained for 30 minutes--recovery from nitrendipine was largely complete at 30 minutes. In conscious dogs, amlodipine (250, 500, 1000 micrograms/kg IV) caused dose-related reductions in systemic vascular resistance that approached maximum within 5 minutes and persisted for over 4 hours. Reflex increases in heart rate, cardiac output, and cardiac contractility were attenuated by prior treatment with propranolol, resulting in earlier and greater falls in blood pressure, but no marked adverse effects on cardiac contraction or conduction. In the absence of propranolol, maximum falls in blood pressure occurred 3 to 4 hours after the dose, possibly as a result of the changed baroceptor sensitivity induced by amlodipine. These results show amlodipine to have the basic hemodynamic profile of other dihydropyridine calcium-channel blockers, but in addition it demonstrates a slower onset and longer duration of action; the reasons behind these pharmacodynamic properties are discussed.


Subject(s)
Adrenergic beta-Antagonists/pharmacology , Calcium Channel Blockers/pharmacology , Hemodynamics/drug effects , Nifedipine/analogs & derivatives , Nitrendipine/pharmacology , Amlodipine , Anesthesia , Animals , Cardiac Output/drug effects , Coronary Circulation/drug effects , Dogs , Dose-Response Relationship, Drug , Female , Male , Nifedipine/pharmacology , Propranolol/pharmacology , Time Factors , Vascular Resistance/drug effects
6.
Neuropharmacology ; 22(1): 35-43, 1983 Jan.
Article in English | MEDLINE | ID: mdl-6133230

ABSTRACT

The heart rate of the anaesthetized rabbit was slowed by electrical stimulation of the hypothalamus with 7-9 sec trains of 250-330 microA pulses, duration 1 msec, frequency 60 Hz. This vagally-mediated cardio-decelerator response was attenuated in a dose-dependent manner after intravenous administration of phenoxybenzamine (0.01-5 mg/kg), phentolamine (0.01-3 mg/kg) or yohimbine (0.1-5 mg/kg). The attenuation of the cardio-decelerator response was not due to any vagolytic action of these drugs nor to block of the baroreceptor reflex, but appeared to be due to a central block of pathways descending from the hypothalamus. Propranolol, haloperidol, pimozide and spiperone did not show this central blocking action except in very large doses when there was evidence of some alpha-adrenoceptor blockade.


Subject(s)
Adrenergic alpha-Antagonists/pharmacology , Blood Pressure/drug effects , Heart Rate/drug effects , Hypothalamus/physiology , Animals , Electric Stimulation , Phenoxybenzamine/pharmacology , Phentolamine/pharmacology , Rabbits , Vagus Nerve/physiology , Yohimbine/pharmacology
7.
Biochemistry ; 21(16): 3842-9, 1982 Aug 03.
Article in English | MEDLINE | ID: mdl-6753921

ABSTRACT

We have determined the sequence of the 25-28 amino-terminal residues of the three subunits, L, M, and H, of the membrane-bound reaction center protein of the photosynthetic bacterium Rhodopseudomonas sphaeroides R-26. The sequences are as follows: L, H2N-Ala-Leu-Leu-Ser-Phe-Glu-Arg-Lys-Tyr-Arg- Val-Pro-Gly-Gly-Thr-Leu-Val-Gly-Gly-Asn-Leu-Phe-Asp-Phe-(His)-Val-; M, H2N-Ala-Glu-Tyr-Gln-Asn-Ile-Phe-Ser-Gln-Val-Gln-Val-Arg-Gly-Pro-Ala-Asp-Leu-Gly-Met-Thr-Glu-Asp-Val-Asn-Leu-Ala-Asn-; H, H2N-Met-Val-Gly-Val-Thr-Ala-Phe-Gly-Asn-Phe-Asp-Leu-Ala-Ser-Leu-Ala-Ile-Tyr-Ser-Phe-Trp-Ile-Phe-Leu-Ala-X-Leu-Ile-. The H sequence, especially after the aspartyl residue at position 11, is rich in hydrophobic residues, consistent with the possibility that this section of the polypeptide chain is located within the membrane. The L sequence is hydrophilic near the amino terminus and then becomes moderately hydrophobic. The M sequence is of average polarity.


Subject(s)
Bacterial Proteins/analysis , Rhodobacter sphaeroides/analysis , Amino Acid Sequence , Autoanalysis , Chromatography, High Pressure Liquid , Macromolecular Substances , Photosynthetic Reaction Center Complex Proteins
8.
Proc Natl Acad Sci U S A ; 79(8): 2504-8, 1982 Apr.
Article in English | MEDLINE | ID: mdl-6953407

ABSTRACT

The complete amino acid sequence of human serum transferrin has been determined by aligning the structures of the 10 CNBr fragments. The order of these fragments in the polypeptide chain is deduced from the structures of peptides overlapping methionine residues and other evidence. Human transferrin contains 678 amino acid residues and--including the two asparagine-linked glycans--has an overall molecular weight of 79,550. The polypeptide chain contains two homologous domains consisting of residues 1-336 and 337-678, in which 40% of the residues are identical when aligned by inserting gaps at appropriate positions. Disulfide bond arrangements indicate that there are seven residues between the last half-cystine in the first domain and the first half-cystine in the second domain and therefore, a maximum of seven residues in the region of polypeptide between the two domains. Transferrin--which contains two Fe-binding sites--has clearly evolved by the contiguous duplication of the structural gene for an ancestral protein that had a single Fe-binding site and contained approximately 340 amino acid residues. The two domains show some interesting differences including the presence of both N-linked glycan moieties in the COOH-terminal domain at positions 413 and 610 and the presence of more disulfide bonds in the COOH-terminal domain (11 compared to 8). The locations of residues that may function in Fe-binding are discussed.


Subject(s)
Transferrin , Amino Acid Sequence , Cyanogen Bromide , Humans , Peptide Fragments/analysis , Protein Conformation
9.
J Urol ; 126(2): 185-6, 1981 Aug.
Article in English | MEDLINE | ID: mdl-7265361

ABSTRACT

A study was undertaken to investigate 3 aspects of 2-layers vas reversal: 1) to determine an appropriate suture size for each layer, 2) to modify available instruments to make them more suitable for vas reversal surgery and 3) to devise a technique for a surgeon to perform alone.


Subject(s)
Sterilization Reversal/methods , Humans , Male , Microsurgery , Vas Deferens/surgery
10.
J Urol ; 124(5): 620-1, 1980 Nov.
Article in English | MEDLINE | ID: mdl-7452787

ABSTRACT

The instruments and method that allow a single operator to do a 2-layer vas anastomosis under the microscope without the aid of an assistant are described. This method of anastomosis should be valuable for microsurgeons who wish to do a single layer anastomosis.


Subject(s)
Microsurgery/methods , Sterilization Reversal/methods , Vas Deferens/surgery , Humans , Male , Microsurgery/instrumentation , Sterilization Reversal/instrumentation
12.
J Biol Chem ; 252(11): 3934-40, 1977 Jun 10.
Article in English | MEDLINE | ID: mdl-324999

ABSTRACT

The amino acid sequence of a proteolytic fragment of Escherichia coli biotin carboxyl carrier protein was determined from the structures of overlapping tryptic, thermolytic, and staphylococcal protease peptides together with automated sequenator analyses on the intact protein. The fragment, 82 residues in length, contains the single residue of biocytin of the protein. The relationship of the Mr = 9100 fragment to the native Mr = 22,500 subunit is discussed.


Subject(s)
Biotin/metabolism , Carrier Proteins , Amino Acid Sequence , Amino Acids/analysis , Bacterial Proteins , Carboxypeptidases , Escherichia coli , Peptide Fragments/analysis , Trypsin
13.
Eur J Biochem ; 51(1): 43-8, 1975 Feb 03.
Article in English | MEDLINE | ID: mdl-1122916

ABSTRACT

The amino acid sequences of three fragments obtained on cyanogen bromide cleavage of human transferrin have been determined. Two of the fragments are small (4 and 7 residues) and had not been isolated in previous studies of the CNBr fragments of transferrin. The sequence of the larger fragment (53 residues) was elucidated by examining peptides isolated from digests of the fragment with trypsin, chymotrypsin or thermolysin. This region of transferrin appears to contain the sites of three previously-reported substitutions in the D1 and D-chi genetic variants.


Subject(s)
Transferrin/analysis , Amino Acid Sequence , Amino Acids/analysis , Aminopeptidases , Binding Sites , Chymotrypsin , Cyanogen Bromide , Cystine/analysis , Genetic Variation , Humans , Oligopeptides/analysis , Peptide Fragments/analysis , Peptides/analysis , Thermolysin , Trypsin
14.
Biochem J ; 139(1): 163-8, 1974 Apr.
Article in English | MEDLINE | ID: mdl-4463940

ABSTRACT

1. Procedures are described for the isolation of seven distinct cyanogen bromide fragments in high yield from human serum transferrin. 2. Cyanogen bromide-cleaved transferrin is separated into three fragments (CN-A, CN-B and CN-C) by gel filtration with Sephadex G-100. 3. Four peptides are obtained from CN-A (the largest fragment) after reduction and carboxamidomethylation, by gel filtration in acidic solvents. Two peptides are similarly obtained from fragment CN-B, whereas fragment CN-C is a single cystine-free peptide. 4. The molecular weights of the seven peptides, as determined by polyacrylamide-gel electrophoresis in the presence of sodium dodecyl sulphate, by sedimentation-equilibrium ultracentrifugation and by sequence studies, range from 3100 to 27000. Together they account for a molecular weight of 76200 for transferrin. 5. The two largest fragments contain the carbohydrate attachment sites of the protein, and the smallest fragment is derived from the N-terminus. 6. The amino acid compositions and N-terminal groups of the fragments are reported and the results compared with those of previous investigations.


Subject(s)
Transferrin , Amino Acid Sequence , Amino Acids/analysis , Centrifugation, Density Gradient , Cyanogen Bromide , Electrophoresis, Polyacrylamide Gel , Humans , Molecular Weight , Peptide Fragments/analysis , Transferrin/analysis
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