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1.
Aquac Nutr ; 2023: 5528942, 2023.
Article in English | MEDLINE | ID: mdl-36909926

ABSTRACT

Atlantic salmon with a start weight of 53 g were fed diets with different levels of EPA and DHA or a diet with 1 : 1 EPA+DHA (0%, 1.0%, and 2.0% of the diet). At 400 g, all fish groups were mixed and equally distributed in new tanks and fed three diets with 0.2%, 1.0%, or 1.7% of EPA+DHA. At 1200 g, the fish were transferred to seawater pens where they were fed the same three diets until they reached a slaughter size of 3.5 kg. The fillet concentration of astaxanthin and its metabolite idoxanthin was analysed before transfer to seawater pens at 1200 g and at slaughter. The fatty acid composition in the fillet was also analysed at the same time points. Salmon fed low levels of EPA and DHA had lower fillet astaxanthin concentration and higher metabolic conversion of astaxanthin to idoxanthin compared to salmon fed higher dietary levels of EPA and/or DHA. DHA had a more positive effect on fillet astaxanthin concentrations than EPA. There were positive correlations between fillet DHA, EPA, sum N-3 fatty acids, and fillet astaxanthin concentration. A negative correlation was found between the concentration of N-6 fatty acids in the fillet and the astaxanthin concentration.

2.
BMC Med Inform Decis Mak ; 23(1): 5, 2023 01 10.
Article in English | MEDLINE | ID: mdl-36627624

ABSTRACT

BACKGROUND: Natural language processing (NLP) based clinical decision support systems (CDSSs) have demonstrated the ability to extract vital information from patient electronic health records (EHRs) to facilitate important decision support tasks. While obtaining accurate, medical domain interpretable results is crucial, it is demanding because real-world EHRs contain many inconsistencies and inaccuracies. Further, testing of such machine learning-based systems in clinical practice has received limited attention and are yet to be accepted by clinicians for regular use. METHODS: We present our results from the evaluation of an NLP-driven CDSS developed and implemented in a Norwegian Hospital. The system incorporates unsupervised and supervised machine learning combined with rule-based algorithms for clinical concept-based searching to identify and classify allergies of concern for anesthesia and intensive care. The system also implements a semi-supervised machine learning approach to automatically annotate medical concepts in the narrative. RESULTS: Evaluation of system adoption was performed by a mixed methods approach applying The Unified Theory of Acceptance and Use of Technology (UTAUT) as a theoretical lens. Most of the respondents demonstrated a high degree of system acceptance and expressed a positive attitude towards the system in general and intention to use the system in the future. Increased detection of patient allergies, and thus improved quality of practice and patient safety during surgery or ICU stays, was perceived as the most important advantage of the system. CONCLUSIONS: Our combined machine learning and rule-based approach benefits system performance, efficiency, and interpretability. The results demonstrate that the proposed CDSS increases detection of patient allergies, and that the system received high-level acceptance by the clinicians using it. Useful recommendations for further system improvements and implementation initiatives are reducing the quantity of alarms, expansion of the system to include more clinical concepts, closer EHR system integration, and more workstations available at point of care.


Subject(s)
Decision Support Systems, Clinical , Hypersensitivity , Humans , Electronic Health Records , Machine Learning , Hospitals
3.
Br J Cancer ; 91(7): 1380-3, 2004 Oct 04.
Article in English | MEDLINE | ID: mdl-15316568

ABSTRACT

Resveratrol inhibits PAH bioactivation through reduced expression of the CYP1A1 and CYP1B1 genes in human bronchial epithelial cells. Ad libitum access to a diet containing resveratrol showed no effect on benzo[a]pyrene-induced lung tumorigenesis in A/J mice. Also, resveratrol did not change CYP1A1 and CYP1B1 gene expression or benzo[a]pyrene protein adduct levels in the lung tissue. The lack of chemopreventive activity may have been caused by insufficient concentrations or nonreactive forms of resveratrol in the lungs.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Aryl Hydrocarbon Hydroxylases/biosynthesis , Cytochrome P-450 CYP1A1/biosynthesis , Gene Expression Regulation, Neoplastic/drug effects , Lung Neoplasms/prevention & control , Stilbenes/pharmacology , Animals , Aryl Hydrocarbon Hydroxylases/genetics , Benzo(a)pyrene/administration & dosage , Benzo(a)pyrene/adverse effects , Chemoprevention , Cytochrome P-450 CYP1A1/genetics , Cytochrome P-450 CYP1B1 , Female , Lung Neoplasms/chemically induced , Lung Neoplasms/veterinary , Mice , Phenols , Resveratrol , Reverse Transcriptase Polymerase Chain Reaction
4.
Br J Cancer ; 91(2): 333-8, 2004 Jul 19.
Article in English | MEDLINE | ID: mdl-15162144

ABSTRACT

Resveratrol (trans-3,4',5-trihydroxystilbene), a phytoalexin present in various plants and foods, has in several in vitro and in vivo studies demonstrated cancer chemopreventive and chemotherapeutic potential. We investigated the in vitro effect of resveratrol on benzo[a]pyrene (B[a]P) -induced DNA adducts in human bronchial epithelial cells. This was compared to the effect of resveratrol on the expression of the cytochrome P450 (CYP) genes CYP1A1 and CYP1B1 and the formation of B[a]P metabolites. Exposure of BEAS-2B and BEP2D cells to B[a]P and increasing concentrations of resveratrol resulted in a dose- and time-dependent inhibition of DNA adduct formation quantified by (32)P-postlabelling. Supporting this result, resveratrol was shown to inhibit CYP1A1 and CYP1B1 gene expression, as measured by real-time reverse transcriptase-polymerase chain reaction. Also, a significant correlation was found between the number of DNA adducts and the mRNA levels of these genes. Using HPLC analysis, a concomitant decrease in the formation of B[a]P-derived metabolic products was detected. In conclusion, these data lend support to a chemopreventive role of resveratrol in polycyclic aromatic hydrocarbon-induced carcinogenesis.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Bronchi/metabolism , DNA Adducts/drug effects , DNA Adducts/metabolism , Epithelial Cells/enzymology , Gene Expression/drug effects , Stilbenes/pharmacology , Aryl Hydrocarbon Hydroxylases/genetics , Aryl Hydrocarbon Hydroxylases/metabolism , Benzo(a)pyrene , Cells, Cultured , Cytochrome P-450 CYP1A1/genetics , Cytochrome P-450 CYP1A1/metabolism , Cytochrome P-450 CYP1B1 , DNA Adducts/genetics , Humans , RNA, Messenger/genetics , RNA, Messenger/metabolism , Resveratrol , Reverse Transcriptase Polymerase Chain Reaction
5.
Vet Res Commun ; 27(7): 513-26, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14609263

ABSTRACT

The influence of zinc bacitracin (ZB) and of Bacillus licheniformis on host microbial-related functions in young piglets was investigated by applying the concept of microflora-associated characteristics. Six biochemical parameters were determined before and after weaning in faecal samples from piglets in four litters having access to a diet containing ZB, to a diet containing B. licheniformis, to a diet with both additives, or to a diet with no additives, from 3 weeks of age. Statistically significant differences were found in three of the intestinal functions investigated: formation of short-chain fatty acids (at 7 and 10 weeks of age). degradation of mucin (at 7 and 10 weeks of age) and conversion of bilirubin to urobilins (at 7 weeks of age). We also found age-dependent influences on the formation of short-chain fatty acids, on conversion of cholesterol to coprostanol and on conversion of bilirubin to urobilins. We conclude that a functional approach is appropriate for measuring exogenous influence(s) on the microbial intestinal metabolisms in weaned piglets.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacillus , Bacitracin/pharmacology , Intestines/microbiology , Probiotics/pharmacology , Swine/microbiology , Animals , Animals, Suckling/microbiology , Bilirubin/metabolism , Cholestanol/metabolism , Cholesterol/metabolism , Dipeptides/metabolism , Fatty Acids, Volatile/metabolism , Feces/chemistry , Mucins/metabolism , Random Allocation , Trypsin/metabolism , Urobilin/metabolism
6.
Res Vet Sci ; 71(1): 27-32, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11666144

ABSTRACT

The dog is able to synthesise ascorbic acid (AA), but is frequently given the vitamin in an attempt to improve health and performance. The pharmacokinetics of AA in this species, however, are not well studied. Using a selective analytical method and careful stability control, the pharmacokinetics of orally given AA was studied in 20 dogs, at two dosage levels (15 and 50 mg kg(-1)) and with two forms of supplement [crystalline AA and the vitamin C product Ester-C(Inter-Cal Corp., Prescott, AZ, USA)]. After oral administration, a rapid increase was found in the plasma level of AA, indicating a possible intestinal active transport mechanism in this species. The obtained C(max)and AUC values were found to increase in a non-linear fashion when the dose of AA was increased. The pharmacokinetic modeling of the elimination of AA was made difficult by a pronounced secondary peak appearing after about 9 hours. The comparison of crystalline AA and Ester-C did not indicate any significant differences in pharmacokinetic parameters between the two preparations of the vitamin.


Subject(s)
Ascorbic Acid/pharmacokinetics , Dogs/metabolism , Administration, Oral , Animals , Area Under Curve , Ascorbic Acid/administration & dosage , Ascorbic Acid/blood , Chemistry, Pharmaceutical , Chromatography, High Pressure Liquid/veterinary , Cross-Over Studies , Dose-Response Relationship, Drug , Regression Analysis
7.
Res Vet Sci ; 71(1): 33-5, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11666145

ABSTRACT

Using a highly sensitive and selective analytical method and careful stability control, plasma concentrations of ascorbic acid were determined in German Shepherd Dogs, Labrador Retrievers and Siberian Huskies, a total 99 animals. Mean concentration was 35.9 micromol l(-1)(range 18.2-50.7), and no significant variation was observed neither between breeds nor between females and males. These and previous reported data on plasma ascorbic acid levels in dogs are discussed in the light of methodological aspects.


Subject(s)
Ascorbic Acid/blood , Dogs/blood , Animals , Chromatography, High Pressure Liquid/veterinary , Female , Male , Reference Values , Regression Analysis
8.
Comp Biochem Physiol B Biochem Mol Biol ; 127(3): 423-32, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11126773

ABSTRACT

Apparent astaxanthin (3,3'-dihydroxy-beta,beta-carotene-4,4'-dione) digestibility coefficients (ADC) and carotenoid compositions of the muscle, liver, whole kidney and plasma were compared in Atlantic salmon (Salmo salar) and Atlantic halibut (Hippoglossus hippoglossus) fed a diet supplemented with 66 mg astaxanthin kg(-1) dry matter for 112 days. The astaxanthin source consisted of 75% all-E-, 3% 9Z- and 22% 13Z-astaxanthin, of (3R,3'R)-, (3R,3'S; meso)-, and (3S,3'S)-astaxanthin in a 1:2:1 ratio. The ADC of astaxanthin was significantly higher in Atlantic halibut than in Atlantic salmon after 56 and 112 days of feeding (P < 0.05). The ADC of all-E-astaxanthin was significantly higher than ADC of 9Z-astaxanthin (P < 0.05). Considerably more carotenoids were present in all plasma and tissue samples of salmon than in halibut. Retention of astaxanthin in salmon muscle was 3.9% in salmon and 0 in halibut. All-E-astaxanthin accumulated selectively in the muscle of salmon, and in plasma of salmon and halibut compared with diet. 13Z-astaxanthin accumulated selectively in liver and whole kidney of salmon and halibut, when compared with plasma. A reductive pathway for astaxanthin metabolism in halibut similar to that of salmon was shown by the presence of 3',4'-cis and trans glycolic isomers of idoxanthin (3,3',4'-trihydroxy-beta,beta-carotene-4'-one) in plasma, liver and whole kidney. In conclusion, the higher ADC of astaxanthin in halibut than Atlantic salmon may be explained by lower feed intake in halibut, and the lower retention of astaxanthin by a higher capacity to transform astaxanthin metabolically.


Subject(s)
Fishes/metabolism , Salmo salar/metabolism , beta Carotene/analogs & derivatives , beta Carotene/metabolism , Animals , Atlantic Ocean , Carotenoids/metabolism , Isomerism , Molecular Structure , Xanthophylls
9.
Equine Vet J ; 32(4): 345-50, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10952385

ABSTRACT

This study investigated the influence of zinc bacitracin on the intestinal flora of horses. The functionally active intestinal flora was examined in 6 horses during treatment with zinc bacitracin. Utilising gas chromatography, spectrophotometry, gel electrophoresis and paper chromatography, samples were analysed on biochemical markers reflecting the action of parts of the intestinal flora. The following 5 flora-related functions were studied in faecal samples and intestinal samples from different sections of the hindgut: conversion of cholesterol to coprostanol and of bilirubin to urobilinogens, degradation of mucin and of beta-aspartylglycine and inactivation of tryptic activity. Conversion to coprostanol, conversion to urobilinogens and degradation of mucin were affected by treatment of zinc bacitracin and conversion to coprostanol was most sensitive. All functions were normalised in a short time, in contrast to man and rats. Differences in environmental exposures are probably the reason for a more rapid normalisation of the intestinal flora functions in horses.


Subject(s)
Anti-Bacterial Agents/pharmacokinetics , Bacitracin/pharmacokinetics , Digestive System/metabolism , Digestive System/microbiology , Horses/metabolism , Horses/microbiology , Animals , Bilirubin/metabolism , Cholestanol/metabolism , Cholesterol/metabolism , Chromatography, Gas/veterinary , Chromatography, Paper/veterinary , Dipeptides/metabolism , Electrophoresis, Polyacrylamide Gel/veterinary , Female , Intestinal Mucosa/drug effects , Intestinal Mucosa/metabolism , Male , Mucins/metabolism , Spectrophotometry/veterinary , Trypsin/metabolism , Urobilinogen/metabolism
10.
J Med Chem ; 42(20): 4185-92, 1999 Oct 07.
Article in English | MEDLINE | ID: mdl-10514288

ABSTRACT

A bradykinin analogue (H-Arg-Pro-Pro-Gly-Phe-Ser-D-BT-Arg-OH, 3) in which the Pro-Phe dipeptide was replaced by the (3S)[amino]-5-(carbonylmethyl)-2,3-dihydro-1, 5-benzothiazepin-4(5H)-one (D-BT) moiety has been synthesized. The same modification was performed on the potent bradykinin B(2) receptor antagonist HOE 140 (H-D-Arg-Arg-Pro-Hyp-Gly-Thi-Ser-D-Tic-Oic-Arg-OH), in which the -D-Tic-Oic- moiety was replaced by D-BT to yield H-D-Arg-Arg-Pro-Hyp-Gly-Thi-Ser-D-BT-Arg-OH, 1 (JMV1116). These compounds were examined in vitro for their binding affinity toward bradykinin B(1) and B(2) receptors as well as for their ability to interfere with bradykinin-induced contraction of both human umbilical vein and rat uterus. The two compounds 3 and 1 competed with [(3)H]bradykinin binding to the human cloned B(2) receptor giving K(i) values of 13 +/- 2 and 0.7 +/- 0.1 nM, respectively. Unexpectedly, both compounds were full bradykinin B(2) receptor agonists on the human umbilical vein (pD(2) = 6.60 +/- 0.07 for 3 and 6.80 +/- 0.08 for 1) and rat uterus (pD(2) = 7.20 +/- 0.09 for 3 and 7.50 +/- 0.09 for 1) preparations with the same efficacy as bradykinin. In addition 1 induced a concentration-dependent phosphoinositide production in CHO cells expressing the human cloned B(2) receptor. These data provide evidence for a bioactive conformation of bradykinin constrained at the dipeptide Pro-Phe.


Subject(s)
Bradykinin/analogs & derivatives , Receptors, Bradykinin/agonists , Angiotensin-Converting Enzyme Inhibitors/chemistry , Animals , Bradykinin/chemical synthesis , Bradykinin/chemistry , Bradykinin/metabolism , Bradykinin/pharmacology , CHO Cells , Cloning, Molecular , Cricetinae , Drug Design , Female , Humans , In Vitro Techniques , Inositol Phosphates/biosynthesis , Muscle Contraction/drug effects , Muscle, Smooth, Vascular/drug effects , Muscle, Smooth, Vascular/physiology , Radioligand Assay , Rats , Rats, Sprague-Dawley , Receptor, Bradykinin B1 , Receptor, Bradykinin B2 , Receptors, Bradykinin/metabolism , Transfection , Umbilical Cord/drug effects , Umbilical Cord/physiology , Uterine Contraction/drug effects
11.
J Med Chem ; 42(20): 4193-201, 1999 Oct 07.
Article in English | MEDLINE | ID: mdl-10514289

ABSTRACT

We have previously shown that substitution of the D-Tic-Oic dipeptide by a (3S)-[amino]-5-(carbonylmethyl)-2,3-dihydro-1, 5-benzothiazepin-4(5H)-one (D-BT) moiety in the bradykinin B(2) receptor antagonist HOE 140 resulted in a full potent and selective bradykinin B(2) receptor agonist (H-DArg-Arg-Pro-Hyp-Gly-Thi-Ser-D-BT-Arg-OH, JMV1116) exhibiting a high affinity for the human receptor (K(i) 0.7 nM). In the present study, we have investigated the effects of replacement of the D-Tic-Oic moiety by various constrained dipeptide mimetics. The resulting compounds were tested for their binding affinity toward the cloned human B(2) receptor and for their functional interaction with the bradykinin-induced contraction of isolated human umbilical vein. Subsequently, we have designed novel bradykinin B(2) receptor agonists which are likely to be resistant to enzymatic cleavage by endopeptidases and which might represent interesting new pharmacological tools. In an attempt to increase the potency of compound JMV1116, both its N-terminal part and the D-BT moiety were modified. Substitution of the D-arginine residue by a L-lysine residue led to a 10-fold more potent bradykinin B(2) ligand [compound 22 (JMV1465) (K(i) 0.07 nM)], retaining full agonist activity on human umbilical vein. Substitution of the D-BT moiety by a (3S)-[amino]-5-(carbonylmethyl)-2,3-dihydro-8-methyl-1, 5-benzothiazepin-4(5H)-one [D-BT(Me)] moiety led to compound 23 (JMV1609) which exhibited a higher agonist activity (pD(2) = 7.4) than JMV1116 (pD(2) = 6.8).


Subject(s)
Bradykinin/analogs & derivatives , Dipeptides/chemistry , Receptors, Bradykinin/agonists , Animals , Bradykinin/chemical synthesis , Bradykinin/chemistry , Bradykinin/metabolism , Bradykinin/pharmacology , Cell Line , Cloning, Molecular , Female , Humans , In Vitro Techniques , Ligands , Molecular Mimicry , Muscle Contraction/drug effects , Muscle, Smooth, Vascular/drug effects , Muscle, Smooth, Vascular/physiology , Radioligand Assay , Rats , Rats, Sprague-Dawley , Receptor, Bradykinin B2 , Structure-Activity Relationship , Umbilical Cord/drug effects , Umbilical Cord/physiology , Uterine Contraction/drug effects
12.
Law Hum Behav ; 22(5): 519-47, 1998 Oct.
Article in English | MEDLINE | ID: mdl-9833565

ABSTRACT

Because the trier of fact determines the weight to be assigned to an examiner's opinion by assessing the strength and persuasiveness of his or her analysis of the data, it is essential that forensic reports communicate the examiner's reasoning process. This study analyzes community examiners' reports on competence to stand trial (CST), emphasizing the nature of examiners' (1) expressed conceptualizations of CST and (2) reasoning establishing a nexus between CST impairments and symptoms of psychopathology. Expert raters coded 100 randomly selected CST reports with respect to a variety of issues, including the examiners' description of the defendant's psycholegal deficits, provision of specific reasoning to link these deficits to psychopathology, and agreement with a paired examiner's global and specific opinions about the defendant's impairments. CST reports were found to (1) reflect basic operationalizations of competence that fail to incorporate legally relevant facets such as a defendant's decisional capacities and (2) adequately document clinical findings, but fail to describe the reasoning underlying psycholegal conclusions. Examiners demonstrated moderately high levels of agreement on defendant's global CST, but expressed radically divergent bases for this opinion. These findings are discussed in light of legal, ethical, and professional standards of practice.


Subject(s)
Expert Testimony/legislation & jurisprudence , Logic , Mental Competency/legislation & jurisprudence , Adult , Documentation , Ethics, Medical , Female , Humans , Male , Psychopathology , Utah
13.
J Pept Res ; 52(1): 1-14, 1998 Jul.
Article in English | MEDLINE | ID: mdl-9716245

ABSTRACT

The synthesis and pharmacological evaluation of dimer derivatives of the C-terminal fragments of the potent bradykinin antagonist HOE-140, linked through their N-termini, were performed. The influence of peptide moiety length was studied using the succinyl moiety as a linker. Our attention focused on the dimer of the C-terminal tetrapeptide of HOE-140 (compound JMV 980), which displayed some inhibiting activity (IC50 = 247 nM) for bradykinin B2 receptors. Unexpectedly, it was orally active in inhibiting bradykinin-induced hypotension in the rat. Based on this tetrapeptide dimer model, we synthesized pseudotetrapeptide dimer bradykinin antagonists 29 and 33, which exhibited high affinity (Ki = 76 and 61 nM, respectively) for the human cloned B2 receptor. In addition, compound 29 inhibited bradykinin-induced contraction of the human umbilical vein giving a pKB value of 6.45. Compounds 29 and 33 were selective toward B2 receptors because they did not bind to the cloned human B1 receptor up to 10 microM.


Subject(s)
Bradykinin Receptor Antagonists , Bradykinin/analogs & derivatives , Peptides/chemistry , Receptors, Bradykinin/chemistry , Animals , Antihypertensive Agents/chemical synthesis , Bradykinin/pharmacology , Dimerization , Humans , Molecular Structure , Muscle Contraction/drug effects , Muscle, Smooth, Vascular/drug effects , Rats , Receptor, Bradykinin B2
14.
Mol Pharmacol ; 52(2): 292-9, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9271352

ABSTRACT

The aim of this study was to analyze the role of cholecystokinin (CCK(B)) receptor in human lymphoblastic Jurkat T cells. We investigated the trophic effect resulting from activation of such a receptor by using the reporter gene strategy. For this purpose, we transiently transfected Jurkat T cells with the reporter plasmid p[(TRE)3-tk-Luc] and found that CCK-8 was able to dose-dependently induce luciferase expression related to activator protein-1 (AP-1) activation with a maximal response identical to that obtained with compounds known to activate AP-1 complex (quantitatively, the same level of induction was obtained with 1 nM 12-O-tetradecanoylphorbol-13-acetate, 100 microM diacylglycerol, or 4 nM epidermal growth factor). The involvement of the CCK(B) receptor in such a stimulation was demonstrated by the inhibiting effect of the selective CCK(B) receptor antagonist PD-135,158. This effect was confirmed in COS-7 cells transfected with the cDNA of CCK(B) receptor cloned from Jurkat T cells. To better understand the AP-1-dependent luciferase expression in Jurkat T cells, we tested two specific inhibitors of serine/threonine phosphatases-1 and -2A: okadaic acid and calyculin A. These compounds strongly increased the phorbol-12-myristate-13-acetate response, whereas we have not observed a contribution of phosphatase inhibitors on a CCK-8-induced luciferase activity. To confirm that CCK(B) receptors are involved in AP-1 response, we investigated the CCK-8 effect on interleukin-2 expression, a natural endogenous gene regulated by several factors, including AP-1. In Jurkat T cells activated by phorbol-12-myristate-13-acetate and phytohemagglutinin, CCK-8 induced IL-2 expression. This induction was abolished by PD-135,158. Our results indicate that CCK-8 exerts a trophic effect in Jurkat T cells through stimulation of CCK(B) receptors by modulation of expression of AP-1-regulated genes.


Subject(s)
Gene Expression Regulation, Neoplastic , Receptors, Cholecystokinin/physiology , Sincalide/pharmacology , T-Lymphocytes/physiology , Transcription Factor AP-1/physiology , Animals , Binding, Competitive , COS Cells , Cell Division , Cell Line , Cloning, Molecular , Humans , Interleukin-2/genetics , Jurkat Cells , Ligands , Transcription, Genetic/drug effects , Transcriptional Activation
15.
Braz J Med Biol Res ; 29(10): 1253-63, 1996 Oct.
Article in English | MEDLINE | ID: mdl-9181094

ABSTRACT

The synthesis of analogs of the C-terminal tridecapeptide of gastrin is described. These pseudopeptide analogs were obtained either by replacing the C-terminal phenylalanine amide with 2-phenylethylalcohol or with 2-phenylethylamine, or by replacing the peptide bond between Trp and Leu, or between Leu and Asp with an aminomethylene (CH2NH). The ability of these compounds to stimulate gastric acid secretion in anesthetized rats and to inhibit binding of labeled CCK-8 to isolated cells from rabbit fundic mucosa was tested. [desPhe13, Leu11]-HG-12-I-beta-phenylethylester 33, [desPhe13, Leu11]-HG-12-II-beta-phenylethylester 38, [desPhe13, Leu11]-HG-12-I-beta-phenylethylamide 32, and [desPhe13, Leu11]-HG-12-II-beta-phenylethylamide 37 acted as gastrin receptor antagonists, while [Trp10-psi(CH2NH)-Leu11]-HG-13-I 31 and [Trp10-psi(CH2NH)-Leu11]-HG-13-II 36 acted as agonists. Unexpectedly, [Leu11-psi(CH2NH)-Asp12]-HG-13-I 30 and [Leu11-psi (CH2NH)-Asp12]-HG-13-II 35 were almost devoid of affinity for the gastrin receptor.


Subject(s)
Gastrins/biosynthesis , Gastric Acid/metabolism , Gastrins/chemistry , Humans , Peptide Biosynthesis , Receptors, Cholecystokinin/antagonists & inhibitors
16.
Braz. j. med. biol. res ; 29(10): 1253-63, Oct. 1996. ilus, tab
Article in English | LILACS | ID: lil-186171

ABSTRACT

The synthesis of analogs of the C-terminal tridecapeptide of gastrin in described. These pseudopeptide analogs were obtained either by replacing the C-terminal phenylalanine amide with 2-phenylethytalcohol or with 2-phenylethylamine, or by replacing the peptid bond between Trp and Leu, or between Leu and Asp with an aminomethylene (CH2NH). The ability of these compounds to stimulate gastric acid secretion in anesthetized rats and to inhibit binding of labeled CCK-8 to isolated cells from rabbit fundic mucosa was tested. [desPhe13, Leu11]-HG-12-I-beta-phenylethylester 33, [desPhe13, Leu11]-HG-12-II-beta-phenylethylester 38 [desPhe13, Leu11]-HG-12-I-beta-phenylethylamide 32, and [desPhe13, Leu11]-HG-12-II-beta-phenylethylamide 37 acted as gastrin receptor antagonists, while [Trp10-((CH2NH)-Leu11]-HG-13-I 31 and (Trp10-((CH2NH)-Leu11]-HG-13-II 36 acted as agonists. Unexpectedly, [Leu11-((CH2NH)-Asp12]-HG-13-I 30 and [Leu11-((CH2NH)-Asp12]-HG-13-II 35 were almost devoid of affinity for the gastrin receptor.


Subject(s)
Humans , Gastric Acid/metabolism , Gastrins/biosynthesis , Peptides/biosynthesis , Receptors, Cholecystokinin/antagonists & inhibitors , Gastrins/chemistry , Peptides/chemical synthesis
18.
Science ; 245(4923): 1211-5, 1989 Sep 15.
Article in English | MEDLINE | ID: mdl-17747882

ABSTRACT

An analysis of high-resolution microwave images of Saturn and Saturn's individual rings is presented. Radio interferometric observations of Saturn taken at the Very Large Array in New Mexico at wavelengths of 2 and 6 centimeters reveal interesting new features in both the atmosphere and rings. The resulting maps show an increase in brightness temperature of about 3 K from equator to pole at both wavelengths, while the 6-centimeter map shows a bright band at northern mid-latitudes. The data are consistent with a radiative transfer model of the atmosphere that constrains the well-mixed, fully saturated, NH(3) mixing ratio to be 1.2 x 10(-4) in a region just below the NH(3) clouds, while the observed bright band indicates a 25 percent relative decrease of NH(3) in northern mid-latitudes. Brightness temperatures for the classical rings are presented. Ring brightness shows a variation with azimuth and is linearly polarized at an average value of about 5 percent. The variations in ring polarization suggest that at least 20 percent of the ring brightness is the result of a single scattering process.

19.
Farmaco ; 44(7-8): 695-702, 1989.
Article in English | MEDLINE | ID: mdl-2590367

ABSTRACT

The individual degradation rate constants for cefotaxime in aqueous solution were calculated within a pH range of 1.6-10.0 at 37 degrees C from high performance liquid chromatography data. This allowed the general degradation profile of cefotaxime to be decomposed into a degradation profile attributed to the opening of the beta-lactam nucleus and a degradation profile attributed to the deacetylation. From the calculations of the individual rate constants, the activity of degraded cefotaxime solutions could be predicted. In the pH range of injectable solutions of cefotaxime 5-7, roughly equivalent amounts of inactive beta-lactam cleavage products and deacetylated compound which has a different spectrum of antibacterial activity are formed.


Subject(s)
Cefotaxime/metabolism , Anti-Bacterial Agents/analysis , Cefotaxime/analogs & derivatives , Cefotaxime/analysis , Chromatography, High Pressure Liquid , Dealkylation , Hydrogen-Ion Concentration , Potentiometry , Spectrophotometry, Ultraviolet
20.
Pharmacol Toxicol ; 64(3): 262-5, 1989 Mar.
Article in English | MEDLINE | ID: mdl-2726689

ABSTRACT

This study was performed to investigate the absorption, distribution and elimination of orally given radiolabelled bacitracin methylene disalicylate (BMD) in rainbow trout kept in salt water. The level of radioactivity in skeletal muscle tissue remained low, but stable throughout the experiment, while radioactivity in bile and liver tissue increased for about 48 hr, before decreasing. There was a trapping of BMD and/or its metabolites in excretory kidney tissue, where the amount of radioactivity continued to increase when radioactive material was being removed from other tissues. The maximum concentration found in excretory kidney tissue was about 7 times as high as the maximum concentration found in the liver. Even though there is no appreciable absorption of BMD from the gastrointestinal tract in homoiotherms, we found the absorption in rainbow trout to be significant.


Subject(s)
Bacitracin/pharmacokinetics , Salmonidae/metabolism , Trout/metabolism , Animals , Autoradiography , Densitometry , Time Factors
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