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EFFECT OF Yucca schidigera BAGASSE AS SUBSTRATE FOR OYSTER MUSHROOM ON CULTIVATION PARAMETERS AND FRUIT BODY QUALITY. REVISTA MEXICANA DE INGENIERÍA QUÍMICA 2018. [DOI: 10.24275/uam/izt/dcbi/revmexingquim/2018v17n3/valencia] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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A rare case of hemolytic anemia in a pediatric patient due to ring dehiscence after mitral valve repair: utility of real-time three-dimensional imaging and management. Pediatr Cardiol 2014; 35:180-2. [PMID: 24030589 DOI: 10.1007/s00246-013-0787-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Accepted: 08/21/2013] [Indexed: 10/26/2022]
Abstract
A rare case of hemolytic anemia in a 3-year-old child due to mitral valve ring dehiscence is described. The dehiscence of mitral valve ring was diagnosed utilizing real-time three-dimensional echocardiography. The patient subsequently underwent reoperation with successful resolution of hemolysis after replacement of the ring.
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Ligand efficiency indices as a navigation tool in the transthyretin protein chemico-biological space to find new amyloidogenic inhibitors. Acta Crystallogr A 2011. [DOI: 10.1107/s0108767311092816] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Drug discovery targeted at transthyretin cardiac amyloidosis: rational design, synthesis, and biological activity of new transthyretin amyloid inhibitors. Amyloid 2011; 18 Suppl 1:55-7. [PMID: 21838431 DOI: 10.3109/13506129.2011.574354019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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LIPOENKEPHALINS: A STUDY OF THE SURFACE ACTIVE AND PHARMACOLOGICAL PROPERTIES OF THESE NEW MORPHINE-LIKE PEPTIDES∗. J DISPER SCI TECHNOL 2010. [DOI: 10.1080/01932698208943643] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Does the HyperCP evidence for the decay Sigma+ -->pmu+mu- indicate a light pseudoscalar Higgs boson? PHYSICAL REVIEW LETTERS 2007; 98:081802. [PMID: 17359086 DOI: 10.1103/physrevlett.98.081802] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2006] [Indexed: 05/14/2023]
Abstract
The HyperCP Collaboration has observed three events for the decay Sigma+ -->p mu+mu- which may be interpreted as a new particle of mass 214.3 MeV. However, existing data from kaon and B-meson decays provide stringent constraints on the construction of models that support this interpretation. In this Letter we show that the "HyperCP particle" can be identified with the light pseudoscalar Higgs boson in the next-to-minimal supersymmetric standard model, the A10. In this model there are regions of parameter space where the A10 can satisfy all the existing constraints from kaon and B-meson decays and mediate Sigma+ -->p mu+mu- at a level consistent with the HyperCP observation.
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Identification of dynorphin a from zebrafish: a comparative study with mammalian dynorphin A. Neuroscience 2006; 144:675-84. [PMID: 17069980 DOI: 10.1016/j.neuroscience.2006.09.028] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2006] [Revised: 09/05/2006] [Accepted: 09/17/2006] [Indexed: 11/24/2022]
Abstract
We report the cloning and molecular characterization of the zfPDYN. The complete open reading frame for this propeptide is comprised in two exons that are localized on chromosome 23. zfPDYN cDNA codes for a polypeptide of 252 amino acids that contains the consensus sequences for four opioid peptides: an Ile-enkephalin, the neo-endorphins, dynorphin A and dynorphin B. Upon comparison between zebrafish (zfDYN A) and mammalian dynorphin A (mDYN A) it has been stated that these two peptides only differ in two amino acids: the Leu(5) is replaced by Met(5) and the Lys(13) by Arg(13). Taking into consideration that mDYN A is able to bind to the three mammalian opioid receptors, we have compared the pharmacological profile of zfDYN A and mDYN A on the zebrafish opioid receptors. By means of radioligand binding techniques, we have established that these two dynorphins bind and activate all of the cloned opioid receptors from zebrafish (delta-, mu- and kappa-like), although with different affinities. zfDYN A and mDYN A displace [(3)H]-diprenorphine binding with K(i) values on the nanomolar range, showing greater affinity for zebrafish opioid receptor (ZFOR) 3 (kappa) receptor. ZFOR1 (delta) and ZFOR4 (delta) present higher affinity for zfDYN A than for mDYN A, while the opposing behavior is observed in ZFOR2 (mu). Functional [(35)S]guanosine 5'-[gamma-thio]triphosphate (GTPgammaS) stimulation experiments indicate that these two peptides fully activate the zebrafish opioid receptors, although the mean effective dose (EC(50)) values obtained for ZFOR2 and ZFOR3 receptors are lower than those seen for ZFOR1 and ZFOR4. A comparative study indicates that mammalian and zebrafish opioid receptors might bind their corresponding dynorphin A in a similar fashion, hence suggesting an important role of the opioid system through the vertebrate evolution.
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Binding Profile of the Endogenous Novel Heptapeptide Met-Enkephalin-Gly-Tyr in Zebrafish and Rat Brain. J Pharmacol Exp Ther 2005; 314:862-7. [PMID: 15901806 DOI: 10.1124/jpet.105.084558] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Zebrafish is considered a model organism, not only for the study of the biological functions of vertebrates but also as a tool to analyze the effects of some drugs or toxic agents. Five opioid precursor genes homologous to the mammalian opioid propeptide genes have recently been identified; one of these, the zebrafish proenkephalin, codes a novel heptapeptide, the Met-enkephalin-Gly-Tyr (MEGY). To analyze the pharmacological properties of this novel ligand, we have labeled it with tritium ([(3)H]MEGY). In addition, we have also synthesized two analogs: (d-Ala(2))-MEGY (Y-d-Ala-GFMGY) and (d-Ala(2), Val(5))-MEGY (Y-d-Ala-GFVGY). The binding profile of these three agents has been studied in zebrafish and rat brain membranes. [(3)H]MEGY presents one binding site in zebrafish, as well as in rat brain membranes, although it shows a slight higher affinity in zebrafish brain. The observed saturable binding is displaced by naloxone, thus confirming the opioid nature of the binding sites. Competition binding assays indicate that the methionine residue is essential for high-affinity binding of MEGY and probably of other peptidic agonists in zebrafish, whereas the change of a Gly for a d-Ala does not dramatically affect the ligand affinity. Our results show that the percentage of [(3)H]MEGY displaced by all the ligands studied is higher than 100%, thus inferring that naloxone (used to determine nonspecific binding) does not bind to all the sites labeled by [(3)H]MEGY. Therefore, we can deduct that some of the MEGY binding sites should not be considered classical opioid sites.
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Crystal structure of human transthyretin in complex with iodo-diflunisal, a potent amyloid inhibitor. Acta Crystallogr A 2004. [DOI: 10.1107/s0108767304097302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Application of empirical design methodologies to the study of the influence of reaction conditions andN-α-protecting group structure on the enzymatic X-Phe-Leu-NH2dipeptide synthesis in buffer/dimethylformamide solvents systems. Biotechnol Bioeng 2004; 39:539-49. [DOI: 10.1002/bit.260390509] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Abstract
BACKGROUND Platelet-activating factor (PAF) is a heterogeneous phospholipid that has been implicated as participating in a number of perinatal disease processes including necrotizing enterocolitis (NEC). METHODS Baseline blood levels of PAF and related lipids (PAF-LL) were measured for 164 infants at risk for NEC from 3 neonatal intensive care units. Serial levels were obtained from the 11 infants in whom NEC developed. RESULTS The mean peak PAF-LL in the infants without NEC was 2.03 +/- 1.96 ng/mL. Infants with stage II (n = 6) and III (n = 5) NEC had elevated peak PAF-LL values (mean peak value 13.6 +/- 6.9 ng/mL). No PAF-LL measurements obtained from infants during stage II or III NEC were <2.03 ng/mL. Three infants had PAF-LL elevations before the development of any clinical or radiographic evidence of NEC. PAF-LL level increased as the severity of NEC increased and decreased with its resolution. Setting a PAF-LL level of 10.2 ng/mL as a cutoff for NEC had a positive predictive value of 100%. CONCLUSIONS PAF-LL determinations can complement clinical and radiographic studies to diagnose and follow the progression of NEC. PAF-LL may have a role in the evolution of NEC.
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Lectin purified human class I MHC-derived peptides: evidence for presentation of glycopeptides in vivo. TISSUE ANTIGENS 2000; 56:129-35. [PMID: 11019912 DOI: 10.1034/j.1399-0039.2000.560203.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Previously, using synthetic glycopeptides carrying a natural cytosolic type of monosaccharide O-beta-linked N-acetylglucosamine (GlcNAc) glycosylation of serine residues, we have shown that glycopeptides act as suitable substrates for TAP-mediated transport into the endoplasmic reticulum (ER), and that they bind efficiently to class I major histocompatibility complex (MHC) molecules and can elicit glycopeptide-specific cytotoxic T-lymphocyte (CTL) responses in mice. Recently, we have reported that peptides presented by human class I MHC molecules in vivo encompass a small but significant amount of peptides which seem to be carrying O-beta-linked monosaccharide GlcNAc. In the present report we provide further evidence that glycosylated peptides are indeed presented by class I MHC molecules in vivo. Thus, peptides derived from HLA-A*0201 were purified by wheat germ agglutinin (WGA) lectin affinity chromatography as previously described. Subsequently, the peptides contained in the WGA-eluate were subjected to sequence analysis by Edman degradation. It was found that the peptides derived from HLA-A*0201 which had been retained by the O-GlcNAc-binding lectin WGA did indeed carry a HLA-A*0201 binding motif. Furthermore, using an enzymatic labeling procedure we present evidence that the HLA-A*0201-derived peptides which bind to the WGA lectin are glycosylated with terminal GlcNAc residues. Together, these data provide further evidence for the natural presentation by human class I MHC of glycopeptides carrying terminal O-GlcNAc residues in vivo.
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Exposure to air pollution is associated with lung hyperinflation in healthy children and adolescents in Southwest Mexico City: a pilot study. Inhal Toxicol 2000; 12:537-61. [PMID: 10880143 DOI: 10.1080/089583700402905] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Air pollution produces adverse health effects. The consequences of lifelong daily exposures to atmospheric pollutants upon the respiratory apparatus of healthy children are of considerable clinical importance. We investigated the association between exposure to a highly polluted urban environment with a complex mixture of air pollutants-ozone and particulate matter the predominant ones-and chest x-ray abnormalities in 59 healthy Mexican children who are lifelong residents of Southwest Metropolitan Mexico City (SWMMC), with a negative history of tobacco exposure and respiratory illnesses. Their clinical results and x-ray findings were compared to those of 19 Mexican control children, residents of a low-pollution area, with a similar negative history of tobacco exposure and respiratory illnesses. Ozone concentrations in SWMMC exceeded the U.S. Environmental Protection Agency (U.S. EPA) National Ambient Air Quality Standard (NAAQS) for O(3): 0.08 ppm as 1-h maximal concentration, not to be exceeded more than 4 times a year, on 71% of days in 1986 and 95% in 1997, with values as high as 0.48 ppm. Ozone maximal peaks are usually recorded between 2 and 5 pm coinciding with children's outdoor physical activities. Children in the control group reported no upper or lower respiratory symptomatology. Every SWMMC child complained of upper and/or lower respiratory symptoms, including epistaxis, nasal dryness and crusting, cough, shortness of breath, and chest discomfort. Children aged 7-13 yr had the most symptomatology, while 5- to 6-year olds and adolescents with the lowest number of statistically significant outdoor exposure hours had less respiratory symptoms. Bilateral symmetric mild lung hyperinflation was significantly associated with exposure to the SWMMC atmosphere (p = .0004). Chronic and sustained inhalation of a complex mixture of air pollutants, including ozone and particulate matter (PM), is associated with lung hyperinflation, suggestive of small airway disease, in a population of clinically healthy children and adolescents. Small airways are a target of air pollutants in SWMMC children, with ozone and PM being most likely responsible, based on experimental animal, controlled-chamber, and epidemiological data available. Our main concern is the potential likelihood for the development of chronic lung disease in this highly exposed population.
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Phosphorylated peptides can be transported by TAP molecules, presented by class I MHC molecules, and recognized by phosphopeptide-specific CTL. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1999; 163:3812-8. [PMID: 10490979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
CTL recognize short peptide fragments presented by class I MHC molecules. In this study, we examined the effect of phosphorylation on TAP transport, binding to class I MHC molecules, and recognition by CTL of peptide fragments from known phosphorylated oncogene proteins or virus phosphoproteins. We show that phosphopeptides can be efficiently transported from the cytosol to the endoplasmic reticulum by the TAP. Furthermore, we show that phosphorylation can have a neutral, negative, or even a positive effect on peptide binding to class I MHC. Finally, we have generated phosphopeptide-specific CTL that discriminate between the phosphorylated and the nonphosphorylated versions of the peptide. We conclude that phosphopeptide-specific CTL responses are likely to constitute a subset of the class I MHC-restricted CTL repertoire in vivo.
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Presentation of cytosolic glycosylated peptides by human class I major histocompatibility complex molecules in vivo. J Exp Med 1999; 190:145-50. [PMID: 10429679 PMCID: PMC2195561 DOI: 10.1084/jem.190.1.145] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/1998] [Accepted: 04/22/1999] [Indexed: 01/09/2023] Open
Abstract
Antigens presented by class I major histocompatibility complex (MHC) molecules for recognition by cytotoxic T lymphocytes consist of 8-10-amino-acid-long cytosolic peptides. It is not known whether posttranslationally modified peptides are also presented by class I MHC molecules in vivo. Many different posttranslational modifications occur on cytoplasmic proteins, including a cytosolic O-beta-linked glycosylation of serine and threonine residues with N-acetylglucosamine (GlcNAc). Using synthetic glycopeptides carrying the monosaccharide O-beta-GlcNAc substitution on serine residues, we have shown that glycopeptides bind efficiently to class I MHC molecules and elicit a glycopeptide-specific cytotoxic T lymphocyte response in mice. In this study, we provide evidence that peptides presented by human class I MHC molecules in vivo encompass a small, significant amount of glycopeptides, constituting up to 0.1% of total peptide. Furthermore, we find that carbohydrate structures present on glycopeptides isolated from class I MHC molecules are dominated by the cytosolic O-beta-GlcNAc substitution, and synthetic peptides carrying this substitution are efficiently transported by TAP (transporter associated with antigen presentation) into the endoplasmic reticulum. Thus, in addition to unmodified peptides, posttranslationally modified cytosolic peptides carrying O-beta-linked GlcNAc can be presented by class I MHC molecules to the immune system.
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Abstract
Two synthetic O-GlcNAc-bearing peptides that elicit H-2Db-restricted glycopeptide-specific cytotoxic T cells (CTL) have been shown to display nonreciprocal patterns of cross-reactivity. Here, we present the crystal structures of the H-2Db glycopeptide complexes to 2.85 A resolution or better. In both cases, the glycan is solvent exposed and available for direct recognition by the T cell receptor (TCR). We have modeled the complex formed between the MHC-glycopeptide complexes and their respective TCRs, showing that a single saccharide residue can be accommodated in the standard TCR-MHC geometry. The models also reveal a possible molecular basis for the observed cross-reactivity patterns of the CTL clones, which appear to be influenced by the length of the CDR3 loop and the nature of the immunizing ligand.
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Association between type II diabetes and generalized alveolar bone loss. J Clin Epidemiol 1998. [DOI: 10.1016/s0895-4356(98)90019-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Study of anomalous couplings at a 500 GeV e+e- linear collider with polarized beams. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1996; 53:4811-4821. [PMID: 10020477 DOI: 10.1103/physrevd.53.4811] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Limits on nonstandard top quark couplings from electroweak measurements. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1996; 53:1721-1724. [PMID: 10020165 DOI: 10.1103/physrevd.53.1721] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Quark-lepton unification and rare meson decays. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1994; 50:6843-6848. [PMID: 10017661 DOI: 10.1103/physrevd.50.6843] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Signals for parity violation in the electroweak-symmetry-breaking sector. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1994; 49:2188-2196. [PMID: 10017207 DOI: 10.1103/physrevd.49.2188] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Enzymatic synthesis of X-Phe-Leu-NH2 in low water content systems: influence of the N-alpha protecting group and the reaction medium composition. BIOCHIMICA ET BIOPHYSICA ACTA 1993; 1164:189-96. [PMID: 8329450 DOI: 10.1016/0167-4838(93)90247-o] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The influence of eight different N-terminal protecting groups (For, Ac, Boc, Fmoc, Mal, Pheac, Aloc and Z) on the alpha-chymotrypsin-catalyzed synthesis of the dipeptide derivative X-Phe-Leu-NH2 in organic media was studied. Groups such as Ac, For, Boc, Z, Mal, Pheac and Alloc always rendered good peptide yields (92% to 99%) either in acetonitrile or in ethyl acetate. Good correlations were found between molecular and physico-chemical characteristics of the N-alpha moiety such as the hydrophobicity (log P), ovality and dipole moment and the global reaction rate parameter k'. High k' values were obtained with the less hydrophobic groups, Ac, For and Mal, that have ovality values close to one and the highest dipole moments. Furthermore, it was found that the relative rate of hydrolysis and aminolysis of the acyl-enzyme intermediate expressed as the partition parameter p is affected by the N-alpha moiety of the acyl donor. Correlations between this parameter and the dipole moment of the protecting group were observed.
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KL--> micro+/-e+/- nu nu -bar as a background to KL--> micro+/-e+/-. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1993; 48:209-211. [PMID: 10016074 DOI: 10.1103/physrevd.48.209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Structure-function approach to vector-boson scattering in pp collisions. PHYSICAL REVIEW LETTERS 1992; 69:3274-3277. [PMID: 10046777 DOI: 10.1103/physrevlett.69.3274] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Abstract
alpha-Chymotrypsin deposited on Celite was used to catalyse peptide synthesis reactions between N-protected amino acid esters and leucine amide in organic media with low water content. The influence of the solvent and the thermodynamic water activity on the reaction kinetics was studied. The substrate specificity in the reactions was shown to be a combination of the substrate specificity of the enzyme in aqueous media and the influence of the solvents. The magnitude of the solvent effects differed greatly depending on the substrates used. In hydrophobic solvents high reaction rates were observed and the competing hydrolysis of the ester substrate occurred to only a minor extent. Reactions occurred at water activities as low as 0.11, but the rate constants increased with increasing water activity and were about two orders of magnitude higher at the highest water activity tested (0.97).
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Racemization free coupling of peptide segments. Synthesis of an insect neuropeptide. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1992; 39:528-32. [PMID: 1399272 DOI: 10.1111/j.1399-3011.1992.tb00284.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The total synthesis of the insect neuropeptide derivative Z-Gly-Gly-Ser-Leu-Tyr-Ser-Phe-Gly-Leu-NH2 has been carried out by a convergent solid phase strategy. For the coupling of the N-terminal pentapeptide to the C-terminal tetrapeptide, three different methods were assayed. Racemization of the acyl activated amino acid during the fragment condensation reaction was monitored by HPLC. Best results were obtained by enzymatic coupling in a low water containing media using adsorbed alpha-chymotrypsin. An optically pure product was obtained in 82% yield after 1 h of reaction. Chemical methods such as DIC/HOBt and BOP/HOBt/NMM always rendered highly optically impure products containing 10-20% of the D-epimer.
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Predictors of cocaine use in pregnancy. Obstet Gynecol 1992; 79:641-4. [PMID: 1565342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Several hundred thousand infants are exposed to cocaine in utero every year in the United States. In an attempt to provide services for women abusing drugs, various programs have been proposed for prenatal drug testing. This study was conducted to assess the sensitivity, specificity, and predictive values of screening programs based on a variety of clinical and historical factors. Between October 1988 and March 1989, 1111 parturients who delivered at an inner-city hospital had urine samples and data collected. The urine, linked by code number to the data, which contained no identifiers, was tested anonymously for illicit drugs. We then assessed the associations of a variety of historical and clinical variables with positive toxicologies. An acknowledged history of drug use or a combination of no prenatal care and cigarette use provided the most valid prediction of cocaine use, with a 59.8% sensitivity, 97.5% specificity, 70% positive predictive value, and 94.9% negative predictive value for positive urine toxicologic examinations. The addition of clinical data such as low birth weight did not improve predictive values significantly. Although the use of easily available historical data allowed correct identification of 60% of parturients who used cocaine, no combination of factors could detect all users. If it is considered beneficial to identify all users at a given point, then urine toxicology screening would be more appropriate than sole reliance on patient history.
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Optimization and kinetic studies of the enzymatic synthesis of Ac-Phe-Leu-NH2 in reversed micelles. Enzyme Microb Technol 1992. [DOI: 10.1016/0141-0229(92)90168-n] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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gamma gamma --> pi 0 pi 0 and KL--> pi 0 gamma gamma in the chiral quark model. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1991; 44:3555-3561. [PMID: 10013816 DOI: 10.1103/physrevd.44.3555] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Testing electroweak symmetry breaking through gluon fusion at pp colliders. PHYSICAL REVIEW LETTERS 1991; 67:2256-2259. [PMID: 10044380 DOI: 10.1103/physrevlett.67.2256] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Influence of solvent and water activity of kinetically controlled peptide synthesis. Enzyme Microb Technol 1991. [DOI: 10.1016/0141-0229(91)90020-b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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The biologic and social consequences of perinatal cocaine use in an inner-city population: results of an anonymous cross-sectional study. Am J Obstet Gynecol 1991; 164:625-30. [PMID: 1992714 DOI: 10.1016/s0002-9378(11)80036-0] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Cocaine use among pregnant women and reports of its adverse perinatal consequences have increased substantially over the past 10 years. However, most researchers have studied patients registered at drug treatment centers or have relied on voluntary participation by patients, either of which introduces the possibility of selection bias. To determine the frequency and consequences of prenatal cocaine use among an unselected inner-city obstetric population, we collected urine samples from parturient women at a municipal hospital and anonymously tested these specimens for metabolites of cocaine, marijuana, opiates, and methadone. Urine specimens, with linked obstetric data sheets, were available from a study population of 1111 patients, and pediatric data sheets were available for 846 mother-infant pairs. Cocaine metabolites were found in 11.5% of the urine samples collected, whereas metabolites of marijuana, opiates, and methadone, respectively, were present in 1.1%, 1.2%, and 0.3% of the specimens. Cocaine users were more likely than nonusers to have had no prenatal care (51% vs 8.8%; p less than 0.0001), to be American-born rather than Caribbean-born (71% vs 33%; p less than 0.001), and to have a higher parity (1.83 vs 1.14; p less than 0.0001). Infants of cocaine users had a lower mean gestational age (-0.93 weeks; p less than 0.01), a lower mean birth weight (2560 +/- 788 vs 3151 +/- 699 gm; p less than 0.001), and an increased probability of having an Apgar score of less than 7 at 5 minutes (12.5% vs 3.2%; p less than 0.0001). Multiple linear regression analysis that isolated confounding variables such as the presence or absence of prenatal care, maternal age and parity, and the use of cigarettes and alcohol did not substantially affect the differences described above. The effect of cigarette smoking on reducing fetal size was cumulative. In conclusion, cocaine is the most commonly used illicit drug among parturients in this community and is strongly associated with underutilization of prenatal care services. Infants of cocaine users are more likely to be preterm and depressed at birth and to have a low birth weight. Cocaine use, through the above-noted effects, increases the need for prenatal care while simultaneously decreasing the likelihood that it will be obtained.
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Goldstone-boson equivalence theorem and the Higgs resonance. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1990; 42:853-859. [PMID: 10012907 DOI: 10.1103/physrevd.42.853] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Neutral-Higgs-boson contribution to the electric dipole moment of the neutron. PHYSICAL REVIEW. D, PARTICLES AND FIELDS 1990; 41:1562-1567. [PMID: 10012510 DOI: 10.1103/physrevd.41.1562] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Synthesis and purification of two SP (6-11) analogues with enhanced selectivity for the NK-1 receptor. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1990; 35:123-7. [PMID: 1691155 DOI: 10.1111/j.1399-3011.1990.tb00246.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Two hexapeptide analogues of Substance P (6-11) have been synthesized. Replacement of Gly9 by proline provides a peptide with tenfold enhanced selectivity for the NK-1 receptor. The corresponding proline-containing glycopeptide incorporating a beta-D-glucopyranosyl residue linked to the side-chain of Glu6 was 100 times more selective than Substance P for the same receptor.
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A synthetic glycopeptide of substance P analogue (SP6-11) with enhanced NK-1 receptor specificity. J Pharm Sci 1990; 79:74-6. [PMID: 1690289 DOI: 10.1002/jps.2600790117] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
A new glycopeptide analogue of substance P (6-11) (SP6-11), namely, N1,6 (beta-D-glucopyranosyl) [Glu6, Pro9]SP6-11, has been synthesized and found to be water soluble. The in vitro biological activity of this glycopeptide was determined for spasmogenic activity in the guinea pig ileum and for potentiation of electrically evoked contractions in the rat vas deferens. Thus, activities on NK-1, NK-2, and NK-3 receptor types have been differentiated by two assays and, in the case of NK-1 and NK-3, receptors in guinea pig ileum (GPI) were assayed using specific pharmacological procedures. The ED50 values for the analogue and reference peptides substance P (SP), neurokinin A(NKA), and neurokinin B (NKB) were determined and potencies relative to SP were calculated. The analogue is three times more potent than the potent NK-1 agonist SP on NK-1 receptors. Moreover, this glycopeptide proved to be as selective for the NK-1 receptor as the specific agonist SPOMe (the methyl ester of substance P).
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Abstract
The antinociceptive activity of two new enkephalin analogues: N1.5-(beta-D-glucopyranosyl)[D-Met2, Pro5]enkephalinamide and N1.5-(beta-D-galactopyranosyl)[D-Met2, Pro5]enkephalinamide was assessed using the tail immersion and paw pressure behavioural tests. Both enkephalin analogues appear to be more active than morphine when injected either into the fourth ventricle or intrathecally; the galactose analogue is more than 5000 times more active than morphine when injected into the fourth ventricle. The analgesic effects produced by the analogues are partially reversed by SC naloxone (0.1 mg/kg) and totally reversed when the dose of naloxone used was 1 mg/kg, suggesting that the analogues act upon more than one type of opiate receptor (mu/delta).
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Abstract
The relative potencies of a series of substance P (6-11) analogues have been determined for spasmogenic activity in the guinea pig ileum in vitro and for potentiation of electrically evoked contractions in the rat vas deferens in vitro. ED50 values were determined for the new analogues. Substance P and its methyl ester were used as standard agonists. Substitution of Gly9 by Pro on [Glu6]SP(6-11) increased four times the activity on the NK-1 receptor. The glycosilation of [Glu6]SP(6-11) by the incorporation of a beta-D-glucopyranosyl amide residue on the gamma-carboxyl group of Glu6 reduced both the activity and selectivity. The simultaneous substitution of Gly9 by Pro and the incorporation of a monosaccharide moiety on the gamma-carboxyl of Glu6 on [Glu6]SP(6-11) yielded an analogue with 60-fold enhanced selectivity relative to substance P for the NK-1 receptor. These results may indicate that the critical factor providing potency to SP(6-11) analogues is mostly related to conformational rather than hydrophilicity aspects of the molecular structure.
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Synthesis and conformational analysis of a series of galactosyl enkephalin analogues showing high analgesic activity. EMBO J 1989; 8:2925-32. [PMID: 2583086 PMCID: PMC401360 DOI: 10.1002/j.1460-2075.1989.tb08442.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Two galactosyl derivatives of [DMet2,Pro5] enkephalin-amide (compound 1), namely [DMet2,Pro5] enkephalin [N1.5-beta-D-galactopyranosyl] amide (compound 2) and O1.5-(beta-D-galactopyranosyl) [DMet2,Hyp5] enkephalin-amide (compound 3) have been synthesized. Such glycosylpeptides have been shown to be extremely potent analgesic agonists. The conformational analysis of these three compounds in DMSO-d6 solution has been carried out using two-dimensional NMR methods. Both the parent compound (1) and the beta N-galactosyl derivative (2) show similar NMR parameters which are consistent with fairly rigid beta-strands at both the N-terminus and C-terminus, connected by a glycine residue that displays a mixture between multiple conformational states. Thus, although the beta N-galactosyl derivative (2) has been shown to be significantly more potent than the parent compound (1) in the tail immersion and paw pressure tests of analgesia, no correlation can be established between the conformation of (1) and (2) in DMSO and the difference in analgesic activity. In contrast, important conformational differences with respect to (1) and (2) have been detected in the beta O-galactosyl derivative (3). In this case, only one of the likely conformations for (1) and (2) are consistent with the experimental data. These data show that the position of the galactose residue in compound (3) causes Gly3 to loose flexibility leading to a more rigid folded conformation. Such a change in conformation could be related to the difference in analgesic activity between (2) and (3).
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