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1.
BJOG ; 128(3): 584-592, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33426798

RESUMO

OBJECTIVE: To evaluate the impact of a care bundle (antenatal information to women, manual perineal protection and mediolateral episiotomy when indicated) on obstetric anal sphincter injury (OASI) rates. DESIGN: Multicentre stepped-wedge cluster design. SETTING: Sixteen maternity units located in four regions across England, Scotland and Wales. POPULATION: Women with singleton live births between October 2016 and March 2018. METHODS: Stepwise region by region roll-out every 3 months starting January 2017. The four maternity units in a region started at the same time. Multi-level logistic regression was used to estimate the impact of the care bundle, adjusting for time trend and case-mix factors (age, ethnicity, body mass index, parity, birthweight and mode of birth). MAIN OUTCOME MEASURES: Obstetric anal sphincter injury in singleton live vaginal births. RESULTS: A total of 55 060 singleton live vaginal births were included (79% spontaneous and 21% operative). Median maternal age was 30 years (interquartile range 26-34 years) and 46% of women were primiparous. The OASI rate decreased from 3.3% before to 3.0% after care bundle implementation (adjusted odds ratio 0.80, 95% CI 0.65-0.98, P = 0.03). There was no evidence that the effect of the care bundle differed according to parity (P = 0.77) or mode of birth (P = 0.31). There were no significant changes in caesarean section (P = 0.19) or episiotomy rates (P = 0.16) during the study period. CONCLUSIONS: The implementation of this care bundle reduced OASI rates without affecting caesarean section rates or episiotomy use. These findings demonstrate its potential for reducing perineal trauma during childbirth. TWEETABLE ABSTRACT: OASI Care Bundle reduced severe perineal tear rates without affecting caesarean section rates or episiotomy use.


Assuntos
Parto Obstétrico/normas , Lacerações/epidemiologia , Complicações do Trabalho de Parto/epidemiologia , Melhoria de Qualidade/estatística & dados numéricos , Adulto , Canal Anal/lesões , Cesárea/efeitos adversos , Cesárea/normas , Cesárea/estatística & dados numéricos , Análise por Conglomerados , Parto Obstétrico/efeitos adversos , Parto Obstétrico/estatística & dados numéricos , Inglaterra/epidemiologia , Episiotomia/efeitos adversos , Episiotomia/normas , Episiotomia/estatística & dados numéricos , Feminino , Humanos , Lacerações/prevenção & controle , Modelos Logísticos , Complicações do Trabalho de Parto/prevenção & controle , Períneo/lesões , Gravidez , Projetos de Pesquisa , Fatores de Risco , Escócia/epidemiologia , País de Gales/epidemiologia
2.
Plant J ; 15(1): 27-38, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9744092

RESUMO

A beta-D-glucosidase has been purified to apparent homogeneity from the cotyledons of germinated nasturtium (Tropaeolum majus L.) seedlings during the mobilization of the xyloglucan stored in the cotyledonary cell walls. The purified protein (Mr 76, 000; a glycoprotein; pl > 9.5; apparent pH optimum 4.5; temperature optimum 30 degrees C) catalysed the hydrolysis of p-nitrophenyl-beta-D-glucopyranoside, cello-oligosaccharides, beta-linked glucose disaccharides, and certain xyloglucan oligosaccharides. Glucose disaccharides with different linkages were hydrolysed at different rates [(1-->3) > (1-->4) > (1-->2) > (1-->6)] with significant transglycosylation occurring in the early stages of the reaction. Cello-oligosaccharide hydrolysis was also accompanied by extensive transglycosylation to give transitory accumulations of higher oligosaccharides. At least some of the glycosyl linkages formed during transglycosylation were (1-->6)-beta. Xyloglucan oligosaccharides xylose-substituted at the non-reducing terminal glucose residue (XXXG, XXLG, XLXG and XLLG, where G is an unsubstituted glucose residue, X is a xylose-substituted glucose residue, and L is a galactosylxylose-substituted glucose residue) were not hydrolysed. Some xyloglucan oligosaccharides with an unsubstituted non-reducing terminal glucose residue (GXXG, GXLG and GXG) were hydrolysed, but others (GLXG and GLLG) were not. This indicated steric hindrance by L but not X substitution at the glucose residue next to the one at the non-reducing end of the oligosaccharide. Hydrolysis of xyloglucan oligosaccharides was not accompanied by transglycosylation. Natural xyloglucan subunit oligosaccharides (XXXG, XXLG, XLXG, XLLG) were totally degraded to their monosaccharide components when treated with nasturtium beta-D-galactosidase. (Edwards et al (1988) J. Biol. Chem. 263, 4333-4337), followed by alternations of nasturtium xyloglucan-specific alpha-xylosidase (Fanutti et al (1991) Planta 184, 137-147) and this enzyme. Several extensively overlapping cDNA clones were obtained by RT-PCR and by screening cDNA libraries. A composite, full-length DNA had an open reading frame of 1962 bp, encoding a polypeptide of 654 amino acids, including all N-terminal and internal sequences obtained from the purified beta-glucosidase protein, and a motif resembling plant signal sequences thought to direct proteins to the cell wall. Database searches revealed homology with beta-glucosidases from several sources (plant, bacteria, yeast), notably with glycosylhydrolases of 'Family 3', according to the classification of Henrissat (Henrissat (1991) Biochem. J. 280, 309-316). There was strong sequence homology with a beta-glucan exo-hydrolase from barley (Hrmova et al. (1996) J. Biol. Chem. 271, 5277-5286). The nasturtium beta-glucosidase is ascribed a role in xyloglucan mobilization, and its interaction with the alpha-xylosidase and the beta-galactosidase is modelled.


Assuntos
Glucanos , Oligossacarídeos/metabolismo , Plantas/enzimologia , Polissacarídeos/metabolismo , Xilanos , beta-Glucosidase , Sequência de Aminoácidos , Sequência de Bases , Sequência de Carboidratos , Clonagem Molecular , Cotilédone/enzimologia , DNA Complementar/genética , DNA de Plantas/genética , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Peso Molecular , Plantas/genética , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , beta-Glucosidase/química , beta-Glucosidase/genética , beta-Glucosidase/isolamento & purificação , beta-Glucosidase/metabolismo
3.
Plant Mol Biol ; 23(4): 769-78, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8251630

RESUMO

Acyl-ACP thioesterases are involved in regulating chain termination of fatty acid biosynthesis in plant systems. Previously, acyl-ACP thioesterase purified from Brassica napus seed tissue has been shown to have a high preference for hydrolysing oleoyl-ACP. Here, oligonucleotides derived from B. napus oleoyl-ACP thioesterase protein sequence data have been used to isolate two acyl-ACP thioesterase clones from a B. napus embryo cDNA library. The two clones, pNL2 and pNL3, contain 1642 bp and 1523 bp respectively and differ in the length of their 3' non-coding regions. Both cDNAs contain open reading frames of 366 amino acids which encode for 42 kDa polypeptides. Mature rape thioesterase has an apparent molecular weight of 38 kDa on SDS-PAGE and these cDNAs therefore encode for precursor forms of the enzyme. This latter finding is consistent with the expected plastidial location of fatty acid synthase enzymes. Northern blot analysis shows thioesterase mRNA size to be ca. 1.6 kb and for the thioesterase genes to be highly expressed in seed tissue coincident with the most active phase of storage lipid synthesis. There is some sequence heterogeneity between the two cDNA clones, but overall they are highly homologous sharing 95.7% identity at the DNA level and 98.4% identity at the amino acid level. Some sequence heterogeneity was also observed between the deduced and directly determined thioesterase protein sequences. Consistent with the observed sequence heterogeneity was Southern blot data showing B. napus thioesterase to be encoded by a small multi-gene family.


Assuntos
Brassica/enzimologia , Brassica/genética , Genes de Plantas , Tioléster Hidrolases/genética , Sequência de Aminoácidos , Sequência de Bases , Brassica/embriologia , Clonagem Molecular , Primers do DNA/química , Expressão Gênica , Dados de Sequência Molecular , Família Multigênica , Sondas de Oligonucleotídeos/química , Fragmentos de Peptídeos/química , Proteínas de Plantas/genética , RNA Mensageiro/genética , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico
4.
Plant Mol Biol ; 20(5): 763-80, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1301073

RESUMO

The level of two thioesterases, acyl-CoA thioesterase and acyl-ACP thioesterase was determined during seed maturation in oil seed rape. Both thioesterase activities rose markedly prior to the onset of lipid accumulation, but the induction kinetics suggest that the activities reside on distinct polypeptides. Acyl-ACP thioesterase (EC 3.1.2.14) was purified 2000-fold using a combination of ion exchange, ACP-affinity chromatography, chromatofocusing and gel filtration. Using native gel electrophoresis, and assays for enzymic activity, two polypeptides were identified on SDS-PAGE as associated with the activity. Cleveland mapping of these polypeptides, of 38 kDa component and 33 kDa respectively, demonstrated that they are related. An antibody was prepared against the 38 kDa component, and this also recognises the 33 kDa polypeptide in highly purified preparations. Western blotting of a crude extract identifies one band at 38 kDa consistent with the 33 kDa component being a degradation product generated during purification. The native molecule has a M(r) of 70 kDa indicating a dimeric structure. The enzyme has a pH optimum of 9.5 and shows strong preference for oleoyl-ACP as substrate. The intact enzyme has an N-terminus blocked to protein sequencing. We also found that two other polypeptides co-purify with acyl-ACP thioesterase under native conditions. The N-terminal amino-acid sequence of these polypeptides is shown and their possible identity is discussed.


Assuntos
Brassica/enzimologia , Carbono-Enxofre Ligases , Sementes/enzimologia , Tioléster Hidrolases/isolamento & purificação , Sequência de Aminoácidos , Cromatografia de Afinidade , Cromatografia em Gel , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Indução Enzimática , Escherichia coli/enzimologia , Cinética , Ligases/isolamento & purificação , Ligases/metabolismo , Dados de Sequência Molecular , Peso Molecular , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Tioléster Hidrolases/biossíntese , Tioléster Hidrolases/metabolismo
5.
Biochim Biophys Acta ; 1039(2): 181-8, 1990 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-2194572

RESUMO

An antibody has been raised against rape seed enoyl-ACP reductase. This recognizes both the alpha and beta polypeptides of the enzyme. Immunoblotting of fresh seed demonstrates that beta is not present in seed material, and that it is produced by proteolysis during isolation. It is thus deduced that rape seed enoyl reductase is an alpha 4 homotetramer. Leaf material from both rape and Arabidopsis have an enoyl reductase with a similar electrophoretic mobility to the rape seed enzyme when analyzed on SDS-PAGE. Quantitative immunoassay has demonstrated that the enzyme continually increases during lipid deposition, indicating that an increase in this enzyme is required to sustain high levels of lipid biosynthesis. In vitro translation experiments show that the enzyme is nuclear coded and synthesized as a precursor form. Immunogold electron microscopy has demonstrated that enoyl reductase is located in plastids. It is shown that ACP-Sepharose may be used as a matrix in the purification of enoyl-ACP reductase.


Assuntos
Proteína de Transporte de Acila/metabolismo , Brassica/enzimologia , Oxirredutases/análise , Biossíntese de Proteínas , RNA Mensageiro/genética , Especificidade de Anticorpos , Western Blotting , Brassica/genética , Cromatografia de Afinidade , Enoil-(Proteína de Transporte de Acila) Redutase (NADH) , Indução Enzimática , Técnicas Imunoenzimáticas , Imuno-Histoquímica , Substâncias Macromoleculares , NAD/metabolismo , Oxirredutases/biossíntese , Oxirredutases/genética , Radioimunoensaio , Sementes/enzimologia , Especificidade por Substrato
6.
Eur J Biochem ; 174(2): 287-95, 1988 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-3383847

RESUMO

Acyl-carrier protein (ACP) is a key component involved in the regulation of fatty acid biosynthesis in plants. cDNA clones encoding ACP from Brassica napus (oil seed rape) embryos have been isolated using oligonucleotide probes derived from heterologous ACPs. Analysis of the DNA sequence data, in conjunction with N-terminal amino acid sequence data, revealed ACP to be synthesized from nuclear DNA as a precursor containing a 51-amino-acid N-terminal extension. Immunocytochemical studies showed ACP to be localised solely within the plastids of B. napus seed tissue and it would therefore appear that the N-terminal extension functions as a transit peptide to direct ACP into these organelles. Analysis of several cDNA clones revealed sequence heterogeneity and thus evidence for an ACP multigene family. From ten cDNA clones, six unique genes, encoding five different mature ACP polypeptides, were identified. Northern blot hybridisation studies provide evidence that the seed and leaf forms of rape ACP are encoded by structurally distinct gene sets.


Assuntos
Proteína de Transporte de Acila/genética , Brassica/genética , Regulação da Expressão Gênica , Genes , Proteína de Transporte de Acila/biossíntese , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , DNA/análise , Ácidos Graxos/biossíntese , Código Genético , Imunoquímica , Dados de Sequência Molecular , RNA Mensageiro/análise , Homologia de Sequência do Ácido Nucleico
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