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1.
J Appl Microbiol ; 131(6): 2941-2956, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34028142

RESUMO

AIM: Arbuscular mycorrhizal fungi (AMF) are often regarded as non-specific symbionts, but some AMF communities show host preference in various ecosystems including vineyards. Grapevine plants are very responsive to AMF colonization. Although these fungi have potentially significant applications for sustainable agricultural ecosystems, there is a gap in knowledge regarding AMF-grapevine interactions worldwide and especially in New Zealand. This study focused on identifying AMF taxa colonizing grapevines in New Zealand vineyards and investigated the effect of grapevine rootstocks on AMF community diversity and composition. METHODS AND RESULTS: Denaturing gradient gel electrophoresis (DGGE) and trap cultures were used to characterize the AMF communities. Grapevine roots from three vineyards and nine rootstocks were analysed by DGGE and used in trap cultures for AMF recovery. Trap cultures allowed the recovery of six AMF spore morphotypes that belonged to Ambispora sp., Claroideoglomus sp., Funneliformis sp. and Glomus sp. Bands excised, reamplified and sequenced from the DGGE were assigned to Glomus sp., Rhizophagus sp. and Claroideoglomus sp. The AMF community analyses demonstrated that rootstock significantly (P < 0·05) influenced the AMF community composition in all sites. CONCLUSIONS: The study showed that for a comprehensive identification of AMF, both results from trap culture and molecular work were needed and that the rootstock cultivar was the main driver of the arbuscular mycorrhizal community colonizing the roots. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides a firm foundation for future research exploring the beneficial use of AMF in enhancing grapevine production and sustainability.


Assuntos
Micorrizas , Ecossistema , Fazendas , Fungos , Micorrizas/genética , Nova Zelândia , Raízes de Plantas , Microbiologia do Solo
2.
J Appl Microbiol ; 128(6): 1735-1753, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31981438

RESUMO

AIMS: This research aimed to identify factors influencing endophyte community structure in apple shoots and the bioactivity of cultured representatives against the fungal pathogen Neonectria ditissima. METHODS AND RESULTS: The endophyte community in leaves and stems of the apple cultivars 'Royal Gala' and 'Braeburn' were analysed by a cultivation-independent method (PCR-DGGE) which showed that tissue type, cultivar and site were determinant factors, with the endophyte taxa in 'Royal Gala' more variable than that in 'Braeburn', with leaf endophyte communities typically differing from stems in both cultivars. Seasonal (spring vs autumn) and regional (Nelson vs Hawke's Bay) variations were not obvious in woody stems. A collection of 783 bacterial and 87 fungal endophytes were recovered from leaves and stems of 'Royal Gala', 'Braeburn', 'Scilate' and/or 'Scifresh' from Nelson (nine sites) and Hawke's Bay (five sites) in spring and from Nelson (three sites) in autumn. A dual culture plating assay was used to test their ability to inhibit the mycelial growth of N. ditissima. Thirteen bacterial (mean of percent inhibition ≥20%) and 17 fungal isolates were antagonistic towards N. ditissima. These isolates belonged to the bacterial genera Bacillus and Pseudomonas, and fungal genera Chaetomium, Epicoccum, Biscogniauxia, Penicillium, Diaporthe, Phlyctema and two unidentified fungal isolates. CONCLUSIONS: Endophyte communities in apple shoots were determined by tissue type, cultivar and site. Endophytic bacterial and fungal isolates inhibiting N. ditissima growth in vitro were found. SIGNIFICANCE AND IMPACT OF THE STUDY: These results provided new evidence of factors influencing apple endophyte community in New Zealand. Endophytes with potential to reduce N. ditissima infection were identified, with the potential to be developed into a biocontrol strategy for European canker.


Assuntos
Endófitos/fisiologia , Hypocreales/fisiologia , Malus/microbiologia , Controle Biológico de Vetores/métodos , Doenças das Plantas/prevenção & controle , Antibiose , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Endófitos/classificação , Endófitos/isolamento & purificação , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Nova Zelândia , Componentes Aéreos da Planta/microbiologia , Doenças das Plantas/microbiologia
3.
Adv Exp Med Biol ; 1032: 115-126, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30362095

RESUMO

Diethylnitrosamine-treated male mice were assigned to 4 groups: a casein-based 35% high fat ethanol liquid diet (EtOH), an EtOH diet made with soy protein isolate protein (EtOH/SOY), an EtOH liquid diet supplemented with genistein (EtOH/GEN) and a chow group. EtOH feeding, final concentration 5% (v/v), continued for 16 wks. EtOH increased incidence and multiplicity of basophilic lesions and adenomas compared to the chow group, (p < 0.05). The EtOH/SOY group had reduced adenoma progression when compared to the EtOH and EtOH/GEN group, (p < 0.05). Genistein supplementation had no protective effect. Soy feeding significantly reduced serum ALT concentrations (p < 0.05), decreased hepatic TNFα and CD-14 expression and decreased nuclear accumulation of NFκB protein in EtOH/SOY-treated mice compared to the EtOH group (p < 0.05). With respect to ceramides, high resolution MALDI-FTICR Imaging mass spectrometry revealed changes in the accumulation of long acyl chain ceramide species, in particular C18, in the EtOH group when compared to the EtOH/SOY group. Additionally, expression of acid ceramidase and sphingosine kinase 1 which degrade ceramide into sphingosine and convert sphingosine to sphingosine-1-phosphate (S1P) respectively and expression of S1P receptors S1PR2 and S1PR3 were all upregulated by EtOH and suppressed in the EtOH/SOY group, p < 0.05. EtOH feeding also increased hepatocyte proliferation and mRNA expression of ß-catenin targets, including cyclin D1, MMP7 and glutamine synthase, which were reduced in the EtOH/SOY group, p < 0.05. These findings suggest that soy prevents tumorigenesis by reducing inflammation and by reducing hepatocyte proliferation through inhibition of EtOH-mediated ß-catenin signaling. These mechanisms may involve blockade of sphingolipid signaling.


Assuntos
Suplementos Nutricionais , Etanol/efeitos adversos , Genisteína , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/dietoterapia , Proteínas de Soja/uso terapêutico , Ceramidase Ácida/metabolismo , Animais , Carcinogênese , Dietilnitrosamina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Transdução de Sinais , Esfingolipídeos/metabolismo , beta Catenina/metabolismo
4.
J Appl Microbiol ; 120(4): 999-1009, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26810985

RESUMO

AIMS: The goal was to determine the effect of temperature, light and incubation period on production, germination and bioactivity of Trichoderma atroviride LU132 against Rhizoctonia solani. METHODS AND RESULTS: The incubation temperatures of 20, 25 or 30°C were assessed on the production of T. atroviride conidia under constant light over a 25 and 50 days periods. The resulting conidia were also studied for germination and bioactivity. Conidium production was maximum at 25°C after 20 days. The second peak of conidium production occurred at 45-50 days. Incubation at 25°C after 15 days showed optimum production of T. atroviride LU132. Conidia produced at 30°C gave the greatest germination and bioactivity in comparison with incubation at 20 or 25°C. CONCLUSION: This study indicates that the temperature at which conidia of T. atroviride are produced affects germination and bioactivity. Formulations based on production of the high conidia yield may not result in optimal bioactivity and there is a trade-off between quantity and quality of T. atroviride LU132 conidia. Conidium production was shown to be a continuous process, and increased under a dark/light regime. This is the first report of bimodal conidium production in a Trichoderma biological control agent (BCA), which is likely to be on 20 days cycle, and is dependent on colony age rather than abiotic factors. Conidia produced after 15 days are likely to be the most suitable for use in commercial production of this strain as a BCA. SIGNIFICANCE AND IMPACT OF THE STUDY: Most studies on Trichoderma-based BCA have only shown the effect of culture conditions on the high conidia yield regardless of conidium quality. This study is the first report on conidium quality affected by principal culture conditions for Trichoderma biological control formulations.


Assuntos
Luz , Temperatura , Trichoderma/crescimento & desenvolvimento , Germinação , Rhizoctonia , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/fisiologia , Esporos Fúngicos/efeitos da radiação , Fatores de Tempo , Trichoderma/fisiologia , Trichoderma/efeitos da radiação
5.
J Appl Microbiol ; 121(2): 461-72, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27123762

RESUMO

AIMS: Effects of culture conditions on productivity, germinability and bioactivity of Trichoderma atroviride LU132 conidia were assessed to identify the factors affecting conidium 'fitness' (quantity and quality) and to withstand variable environmental conditions, increase conidial productivity, and perform optimum bioactivity. METHODS AND RESULTS: The interaction effects of temperatures (20 or 30°C) vs hydrocarbon types (dextrose or sucrose in constant C : N 5 : 1) were assessed for bioactivity and colonization potential in pot experiments with ryegrass in the presence of pathogen, Rhizoctonia solani. Trichoderma atroviride produced in different culture conditions increased some growth parameters of ryegrass plant and also reduced the pathogenicity effects of R. solani. For example, Trichoderma colony produced at 20°C with sucrose increased all plant growth parameters and conidia produced at 20°C with dextrose gave the greatest bioactivity. CONCLUSION: The bimodal population cycle in T. atroviride recurred in pot experiments in a manner similar to that previously observed in agar plates but indicating that simulated natural conditions shortened the Trichoderma life cycle. Trichoderma colonized ryegrass root system and symbiotically interacted with ryegrass and greater ryegrass colonization resulted from medium production treatment with dextrose rather than sucrose. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is the first report on the effects of inoculum production conditions on conidium quality of Trichoderma to colonize and to maintain populations in host rhizospheres, and also the ability to promote plant growth and suppress a soil-borne disease. The results of these experiments provide new knowledge on how manipulation of culture conditions of T. atroviride LU132 can influence conidium fitness, as a basis for optimizing commercial production of the fungus as a biological control agent.


Assuntos
Meios de Cultura/metabolismo , Lolium/microbiologia , Doenças das Plantas/microbiologia , Rhizoctonia/crescimento & desenvolvimento , Trichoderma/crescimento & desenvolvimento , Meios de Cultura/química , Lolium/crescimento & desenvolvimento , Doenças das Plantas/prevenção & controle , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Rhizoctonia/metabolismo , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/metabolismo , Temperatura , Trichoderma/metabolismo
6.
Mycorrhiza ; 23(5): 403-10, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23397165

RESUMO

Paenibacillus sp. EJP73 has been previously demonstrated as a mycorrhization helper bacterium (MHB) for the Lactarius rufus-Pinus sylvestris symbiosis in both laboratory and glasshouse experiments. In the present study, the effect of Paenibacillus sp. EJP73 metabolites on L. rufus EO3 pre-symbiotic growth was tested in two agar plate-based systems. Specifically, volatile metabolites were investigated using a dual plate system, in which the presence of strain EJP73 resulted in a significant negative effect on L. rufus EO3 hyphal radial growth but enhanced hyphal branching and reduced internode distance. Soluble metabolites produced by strain EJP73 were tested on L. rufus EO3 growth in single-agar plate assays by incorporating bacterial cell-free whole or molecular weight fraction spent broth into the agar. Whole spent broth had a negative effect on hyphal growth, whereas a low molecular weight fraction (100-1,000) promoted colony radial growth. Headspace and spent broth analysis of strain EJP73 cultures revealed 2,5-diisopropylpyrazine to be the most significant component. Synthesised 2,5-diisopropylpyrazine and elevated CO2 (2,000 ppm) were tested as specific volatile metabolites in the dual plate system, but neither produced the response shown when strain EJP73 was present. Increased pre-symbiotic hyphal branching leading to increased likelihood of plant infection may be an important MHB mechanism for strain EJP73. Although the precise signal molecules could not be identified, the work suggests a number of metabolites may work synergistically to increase L. rufus root colonisation.


Assuntos
Basidiomycota/crescimento & desenvolvimento , Fatores Biológicos/metabolismo , Hifas/crescimento & desenvolvimento , Micorrizas/crescimento & desenvolvimento , Paenibacillus/metabolismo , Pinus sylvestris/microbiologia , Compostos Orgânicos Voláteis/metabolismo , Basidiomycota/efeitos dos fármacos , Fatores Biológicos/química , Fatores Biológicos/farmacologia , Hifas/efeitos dos fármacos , Peso Molecular , Micorrizas/efeitos dos fármacos , Paenibacillus/química , Raízes de Plantas/microbiologia , Compostos Orgânicos Voláteis/farmacologia
7.
Plant Dis ; 97(8): 1113, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30722501

RESUMO

Phoma black leg or stem canker, caused by Leptosphaeria maculans or L. biglobosa, is an important disease of brassicas, causing significant crop losses in areas such as Europe, Australia, and North America (1). Samples collected in 2011 from canola and forage brassica (swede, kale, and turnip) crops in the main New Zealand growing regions (Southland, Central Otago, Canterbury, Hawkes Bay, and Manawatu) to identify the causal agent(s) of the characteristic stem cankers, found many isolates of L. maculans, which has been reported previously in New Zealand (2), and three isolates identified by colony characteristics as L. biglobosa. Of the latter, two isolates were from canola (Brassica napus) stem cankers from Darfield and Lincoln, Canterbury, and one was from a kale (B. oleracea) stem canker from Lincoln. An isolate (ICMP10665) of similar morphology, from the International Collection of Microorganisms from Plants (ICMP), obtained from a basal rot lesion on a cauliflower (B. oleracea var. botrytis) plant in Levin, New Zealand in 1979, was also evaluated. The initial, incorrect identification of the latter isolate as L. maculans predates the reclassification of L. maculans group B isolates as a new species, L. biglobosa (1). These four isolates produced fluffy white mycelium and a yellow pigment on potato dextrose agar (PDA) after 5 days' growth, and abundant black-brown, globose pycnidia containing cylindrical hyaline conidia after 7 days. In contrast, L. maculans isolates had slower growth and no pigment production (4). Amplification of genomic DNA using species-specific primers LmacR, LmacF, and LbigF (1) generated a PCR product of 444 bp that is typical of L. biglobosa isolates. Sequencing of the PCR product from each of the four isolates showed they were 100% identical to a sequence of L. biglobosa 'brassicae' in GenBank (JF740198). To confirm the species identity of the isolates, the rDNA, actin, and ß-tubulin gene regions were amplified (1,3). Sequences for the rDNA (568 bp), actin (941 bp), and ß-tubulin (410 bp) gene regions were 99% identical to sequences of the same regions of isolates in GenBank for L. biglobosa 'brassicae' (AY48997, AY748949.1, and AY748997.1, respectively). The four L. biglobosa isolates were tested for pathogenicity on a canola cultivar commonly grown in New Zealand (Flash). Cotyledons of 10-day-old seedlings (n = 12 seedlings/isolate or control treatment) grown in a potting mix in pots were pricked with a sewing needle, and each wound inoculated with 10 µl of the appropriate conidial suspension (106 conidia/ml) or 10 µl sterilized distilled water for the control treatment. Leaf lesions that developed on the inoculated cotyledons were characteristic of those caused by L. biglobosa, i.e., small and dark with a distinct margin. No pycnidia were produced on the lesions. No lesions developed on the cotyledons of the non-inoculated control plants. The causal agents were confirmed as L. biglobosa by the colony morphology of isolates that grew from surface-sterilized, inoculated leaf lesions plated on PDA amended with 100 µg/ml ampicillin. The fungus was not isolated from control leaf tissue. To our knowledge, this is the first report of L. biglobosa as a pathogen of canola and kale in New Zealand. This finding shows that both causal agents of black leg are present in New Zealand's brassica cropping areas. References: (1) S. Y. Liu et al. Plant Pathol. 55:401, 2006. (2) H. C. Smith and B. C. Sutton. Trans. Brit. Mycol. Soc. 47:159, 1964. (3) L. Vincenot et al. Phytopathology 98:321, 2008. (4) R. H. Williams and B. D. L. Fitt. Plant Pathol. 48:161, 1999.

8.
Plant Dis ; 96(1): 144, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30731865

RESUMO

Isolates morphologically identified as Cylindrocladiella parva were isolated from characteristic black foot symptoms on a grapevine (Vitis vinifera) rooted on 101-14 rootstock from Central Otago in 2005 and 101-14 rootstocks from a nursery in the Auckland Region in 2007 and 2008. On potato dextrose agar, the isolates initially produced cottony, white mycelia that turned grayish cream or golden cream within 10 days, the initially tawny colony undersides becoming dark brown with age. Conidia (0 to 1 septate; 16.4 to 17.0 [16.7] × 2.3 to 2.6 [2.5] µm) and abundant chlamydospores were produced. To confirm identity of the isolates, genomic DNA was extracted and the ribosomal DNA (rDNA) and ß-tubulin gene were amplified and sequenced (3,4). Sequences of the PCR products were compared with sequences in GenBank. The rDNA (535 bp) and ß-tubulin (297 bp) sequences of the four isolates were 100 and 99% identical, respectively, to reported sequences of C. parva in GenBank (AY793454, grapevine isolate (4)/AY793455 for rDNA; AY793486/AY793488, grapevine isolate (4)/AY793489/HM034822 for ß-tubulin). Although C. parva was previously isolated from grapevines in New Zealand (2) and rootstocks of mature grapevines, cuttings, and graft unions of grafted young grapevines in South Africa (4), its role as a pathogen of Vitis spp. has not been confirmed (2,4). However, it has been reported as a pathogen of Eucalyptus spp. (1) and was also isolated from Telopea speciosissima and Macadamia integrifolia in New Zealand (2,4). The C. parva isolates were tested as a mixed inoculum (four isolates) for pathogenicity on roots of 10 grapevine rootstock plants each of cvs. 101-14 and Schwarzmann (Sch). The rootstocks were grown in potting mix for 4 months, after which the root systems of all vines were wounded with an asparagus knife with a sharp, square tip, driven vertically down into the soil at four equidistant locations approximately 8 cm from the trunk. Each plant was inoculated with 50 ml of the mixed-isolate conidial suspension (106/ml), or 50 ml water (controls), followed by 50 ml of water. After 7 months of growth, the plants were harvested. For C. parva-inoculated plants, internal blackening of the stem base tissue was observed. Isolations from surface-sterilized trunk bases recovered C. parva from four and nine plants of 101-14 and Sch, respectively, with C. parva infections in 25 and 48%, respectively, of the four wood pieces taken per plant. Plants inoculated with water had no blackening and no C. parva was isolated from their stem bases. Mean shoot dry weights of inoculated plants (17.9 and 15.0 g for 101-14 and Sch, respectively) were significantly lower (P = 0.035) than noninoculated controls (26.5 and 20.0 g for 101-14 and Sch, respectively). Mean root dry weights were reduced by C. parva inoculation, although not significantly (32.7 and 27.0 g for C. parva inoculated 101-14 and Sch, respectively, and 36.2 and 27.4 g for control 101-14 and Sch, respectively). To our knowledge, this is the first report of C. parva as a pathogen of grapevines (2,4) and suggests that along with Cylindrocarpon spp., C. parva is part of the pathogen complex responsible for black foot of grapevines. References: (1) P. W. Crous et al. Plant Pathol. 42:302, 1993. (2) P. D. Gadgil et al. Fungi on Trees and Shrubs in New Zealand. Fungal Diversity Press, Hong Kong, 2005. (3) N. L. Glass and G. C. Donaldson. Appl. Environ. Microbiol. 61:1323, 1995. (4) G. J. van Coller et al. Australas. Plant Pathol. 34:489, 2005.

9.
Plant Dis ; 94(12): 1504, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30743386

RESUMO

In a 2008 survey, 120 isolates of the Botryosphaeriaceae were recovered from a representative subsample of Vitis vinifera plants and propagation materials collected in nine New Zealand grapevine nurseries. Isolates were identified by amplified ribosomal DNA restriction analysis (ARDRA) (1) as Neofusicoccum luteum (56%), N. parvum (18%), N. australe (8%), Diplodia mutila (7%), Botryosphaeria dothidea (5%), D. seriata (3%), and N. ribis (2%). One isolate (M353) from 1 cm below the graft union of a nonsymptomatic 1-year-old grafted plant from the Nelson Region was not identified by ARDRA and was morphologically distinct from all others. Mycelium produced by the novel isolate on potato dextrose agar (PDA) was initially moderately dense, flat, and white and turned olivaceous brown within 10 days. The isolate did not produce pycnidia in PDA or prune extract agar, but when grown in water agar with sterile pine needles for 8 weeks at 25°C and a 12-h light/dark regimen, small, black pycnidia covered with mycelium were produced but no conidia were observed. To identify the novel fungus, genomic DNA was extracted and the ribosomal DNA (rDNA), ß-tubulin gene, and elongation factor α-1 gene were amplified and sequenced (4). The sequences of the PCR products were compared with sequences present on GenBank. The rDNA (503 bp), ß-tubulin (371 bp), and elongation factor α-1 gene (227 bp) sequences of M353 were 100% identical to reported sequences of N. macroclavatum on GenBank (Accession No. DQ093199/198/196 for rDNA, DQ093207/206 for ß-tubulin, and DQ093219/217 for elongation factor α-1). These genes differed from the same genes in other Neofusicoccum species by at least 11, 2, and 3 base pairs, respectively. The N. macroclavatum isolate was tested for pathogenicity on wounded grapevine (Sauvignon blanc) green shoots and 1-year-old rooted canes (n = 4 per plant type) using mycelium plugs from a 4-day-old PDA culture. Sterile agar was used for the negative control. Green shoots inoculated with N. macroclavatum developed brown lesions with an average length of 40.5 mm 6 days after inoculation. Bark from inoculated 1-year-old canes was peeled off 28 days after inoculation and brown-to-black lesions on the wood, with an average length of 52 mm, were observed. Control plants produced no lesions. The pathogen was consistently reisolated from the inoculated plants while none were found in negative control plants. To our knowledge, this is the first report of N. macroclavatum as a pathogen of grapevines and the first report of its presence in New Zealand (3). N. macroclavatum was first reported as a pathogen of Eucalyptus globulus in Western Australia in 2005 and has not been reported as a pathogen of grapevines (2). References: (1) A. Alves et al. FEMS Microbiol. Lett. 245:221, 2005. (2) T. T. Burgess et al. Australas. Plant Pathol. 34:557, 2005. (3) J. Sammonds et al. N. Z. Plant Prot. 62:248, 2009. (4) B. Slippers et al. Mycologia 96:83, 2004.

10.
Science ; 234(4772): 41-6, 1986 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-17742633

RESUMO

Attempts to understand the personal characteristics of others, in interactions with them, are complicated by the fact that one tends to find what one expects. This happens not only because processing of information is selective, but also because expectancies cause one to act in ways that elicit behavior interpretable as confirming those expectancies, even when the expectancies might have been mistaken. Studies provide ample evidence of such self-fulfilling prophecies in social interaction and are beginning to spell out the crucial steps in the process for confirming expectancies. Such studies help link the psychology of first impressions to the psychology of long-term relationships by showing how expectancies are sustained or modified through behavioral sequences that are partially determined by initial expectancies.

11.
Adv Cancer Res ; 134: 85-116, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28110657

RESUMO

Glycosylated proteins account for a majority of the posttranslation modifications of cell surface, secreted, and circulating proteins. Within the tumor microenvironment, the presence of immune cells, extracellular matrix proteins, cell surface receptors, and interactions between stroma and tumor cells are all processes mediated by glycan binding and recognition reactions. Changes in glycosylation during tumorigenesis are well documented to occur and affect all of these associated adhesion and regulatory functions. A MALDI imaging mass spectrometry (MALDI-IMS) workflow for profiling N-linked glycan distributions in fresh/frozen tissues and formalin-fixed paraffin-embedded tissues has recently been developed. The key to the approach is the application of a molecular coating of peptide-N-glycosidase to tissues, an enzyme that cleaves asparagine-linked glycans from their protein carrier. The released N-linked glycans can then be analyzed by MALDI-IMS directly on tissue. Generally 40 or more individual glycan structures are routinely detected, and when combined with histopathology localizations, tumor-specific glycans are readily grouped relative to nontumor regions and other structural features. This technique is a recent development and new approach in glycobiology and mass spectrometry imaging research methodology; thus, potential uses such as tumor-specific glycan biomarker panels and other applications are discussed.


Assuntos
Biomarcadores Tumorais/metabolismo , Processamento de Imagem Assistida por Computador/métodos , Imagem Molecular/métodos , Neoplasias/patologia , Polissacarídeos/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Animais , Glicosilação , Humanos , Neoplasias/metabolismo
12.
Biochim Biophys Acta ; 383(1): 106-16, 1975 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-1091297

RESUMO

The synthesis of acetylornithine delta-transaminase is induced by arginine and by rifampin in an arginine-inducible mutant of Escherichia coli W. A mutant of the arginine-inducible strain was isolated which is resistant to rifampin. The mutation which has brought about rifampin resistance has altered RNA polymerase and has simultaneously altered the regulation of arginine biosynthesis. Three of the enzymes of arginine biosynthesis, acetylornithinase, ornithine transcarbamylase, and argininosuccinase, show a greater rate of derepression and a 2--12-fold higher level of enzyme activity in the rifampin-resistant mutant than in the parent arginine-inducible strain. Acetylornithine delta-transaminase is no longer inducible by rifampin alone, and the level of inducibility by arginine plus rifampin has been reduced by 70%. The results indicate that RNA polymerase is involved in regulation of arginine biosynthesis in E. coli W.


Assuntos
Arginina/biossíntese , Escherichia coli/enzimologia , Rifampina/farmacologia , Acetamidas , Amidoidrolases , Argininossuccinato Liase/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , Resistência Microbiana a Medicamentos , Escherichia coli/crescimento & desenvolvimento , Galactosidases/metabolismo , Mutação , Ornitina/análogos & derivados , Ornitina Carbamoiltransferase/metabolismo , RNA Bacteriano/biossíntese , Transaminases/metabolismo , Triptofano Sintase/metabolismo , Uridina/metabolismo
13.
J Clin Endocrinol Metab ; 75(2): 636-40, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1639962

RESUMO

We examined whether the proliferative index of granulosa cells as determined by flow cytometry varied with a women's age or ovulation induction regimen that included leuprolide acetate (LA). This prospective cohort study included three groups of patients undergoing assisted reproductive technologies. Group I consisted of 9 women age less than or equal to 30 yr, who received LA plus human menopausal gonadotropin (hMG). Group II included 9 women age more than or equal to 40 yr, who received LA plus hMG. Group III consisted of 6 women age less than or equal to 30 yr who received hMG alone. A total of 79 preovulatory follicles containing greater than 10(4) granulosa cells were obtained from these 24 women and examined by flow cytometry. Group I was compared to group II to match for ovulation induction regimen and to examine proliferative index as a function of age. Group I was compared to group III to match for age and to examine proliferative index as a function of ovulation induction regimen. Outcome measures included proliferative index of granulosa cells as a function of age, ovulation induction regimen, ampules of hMG, estradiol on day of hCG, and serum FSH. Group I demonstrated a greater proliferative index than group II: 23.4% +/- 1.4 vs. 18.4% +/- 0.96 (P less than 0.01). Group I had a greater proliferative index than group III: 23.4% +/- 1.4 vs. 11.9 +/- 0.61 (P less than 0.001). Although both age and the presence of LA appeared to affect the PI, multiple linear regression demonstrated that only the addition of LA and not age, per se, had an independent effect upon granulosa cells undergoing proliferation (P less than 0.0005). We conclude that LA followed by hMG leads to an increase in the percentage of granulosa cells undergoing proliferation when compared to ovulation induction regimens that include hMG alone. Chronological age does not appear to have a significant independent influence upon the proliferative index.


Assuntos
Envelhecimento/metabolismo , DNA/análise , Citometria de Fluxo , Células da Granulosa/química , Indução da Ovulação , Adulto , Contagem de Células , Ciclo Celular , Gonadotropina Coriônica/farmacologia , Fase de Clivagem do Zigoto , Estradiol/sangue , Feminino , Células da Granulosa/citologia , Humanos , Leuprolida/farmacologia , Menotropinas/farmacologia , Oócitos/citologia , Análise de Regressão , Manejo de Espécimes
14.
Am J Med ; 98(1A): 116S-119S, 1995 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-7825631

RESUMO

Androgenic disorders have many negative physical effects. These effects may be caused by excess androgen (exogenous or endogenous) or by end-organ sensitivity to normal levels of androgens. Historically, androgenic progestins in oral contraceptives have also been associated with some of these negative effects. The most apparent signs of androgen excess are the external manifestations, including oily skin, acne, hirsutism, android obesity, and androgenic alopecia. Of equal concern are the potential metabolic disturbances associated with hyperandrogenicity. Unfavorable lipid profiles and increased incidence of diabetes and hypertension are very real threats to long-term health. In oral contraceptive users, external manifestations of androgenicity often lead to poor compliance, decreased efficacy, and discontinuation of oral contraceptive use, especially in the younger patient. With the introduction of the newer oral contraceptive formulations containing less androgenic progestins (norgestimate, desogestrel, gestodene), androgen-related effects have been reduced and better compliance is anticipated.


PIP: One of the primary reasons why women discontinue use of oral contraceptives (OCs) containing androgenic progestins is because of unwanted side effects. A new generation of progestin-based OCs have shown promise in lowering androgenic side effects while preventing pregnancy. Many of these side effects are manifested externally, but there are also long-term health risks due to potential metabolic disturbances and high lipoprotein levels. This paper considers implications of OC androgenic effects for user compliance; it discusses the biologic effects of progestins used in OCs on endometrial tissues; further, it reviews, describes, and compares older OC formulations to new generation OCs in the progestin group. Low doses of progestins in OCs decrease unwanted androgenic side effects. New generation progestin OCs have shown a decreased incidence of unwanted/negative external physical side effects; they also appear to increase high-density lipoprotein (HDL) levels and reduce low-density lipoprotein (LDL) levels. The author concludes that the improved user compliance rate resulted from the prescription of new generation progestin OCs.


Assuntos
Androgênios/fisiologia , Anticoncepcionais Orais Hormonais/efeitos adversos , Feminino , Humanos , Cooperação do Paciente
15.
Brain Res Mol Brain Res ; 119(1): 73-82, 2003 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-14597231

RESUMO

Levels of nerve growth factor (NGF) and neurotrophin-3 (NT-3) protein and neurotrophin receptor mRNA in adult sympathetic neurons were investigated following surgical removal of preganglionic input and/or in vivo administration of NGF. Expression of trkC and p75, but not trkA, was significantly decreased following a 3-week deafferentation of the superior cervical ganglion (SCG). Protein levels of NGF and NT-3 in the SCG were unchanged by deafferentation. A 2-week intracerebroventricular infusion of NGF without deafferentation resulted in enhanced mRNA levels of trkA, trkC, and p75 as well as significantly increased NGF and NT-3 protein in the SCG. When NGF infusion followed deafferentation, both trkA and p75 showed significant increases while trkC levels were similar to control values. NGF protein was not increased in the SCG when deafferentation preceded exogenous NGF, yet NT-3 was elevated and levels were similar to cases receiving NGF infusion only. These results support a role for preganglionic input in trkC and p75 expression in adult sympathetic neurons. The increased levels of NT-3 protein and trkC gene expression observed following NGF infusion suggest that NGF influences NT-3 regulation in adult sympathetic neurons. In addition, the present findings provide evidence that, when preganglionic input is removed prior to the NGF infusion, NT-3 effectively competes with NGF for trkA binding. Taken together, we propose that NT-3 may play a role in the robust sprouting of sympathetic cerebrovascular axons previously observed following NGF administration, particularly when deafferentation precedes the NGF infusion period.


Assuntos
Vias Aferentes/fisiologia , Fibras Autônomas Pré-Ganglionares/fisiologia , Fator de Crescimento Neural/metabolismo , Neurotrofina 3/metabolismo , Receptores de Fator de Crescimento Neural/genética , Gânglio Cervical Superior/crescimento & desenvolvimento , Vias Aferentes/lesões , Vias Aferentes/cirurgia , Animais , Denervação , Feminino , Cones de Crescimento/efeitos dos fármacos , Cones de Crescimento/metabolismo , Fator de Crescimento Neural/farmacologia , Plasticidade Neuronal/efeitos dos fármacos , Plasticidade Neuronal/fisiologia , Neurotrofina 3/farmacologia , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor de Fator de Crescimento Neural , Receptor trkA/genética , Receptor trkC/genética , Gânglio Cervical Superior/efeitos dos fármacos , Gânglio Cervical Superior/metabolismo
16.
J Reprod Immunol ; 32(3): 201-19, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9080384

RESUMO

There is a considerable population of macrophages (5-15% of the cells) within the human ovarian follicle at the time of ovulation. Macrophages are also present within the ovarian stroma, mostly near perifollicular capillaries. We hypothesized that macrophage migration in and around the preovulatory follicle is hormonally regulated and that regulation of macrophage migration occurs through local modulation of monocyte chemotactic protein-1 (MCP-1) that chemoattracts and activates monocytes/macrophages. In this regard, we investigated the expression and regulation of MCP-1 in human follicular fluid and in ovarian stromal and granulosa-lutein cell cultures. The concentration of MCP-1 in follicular fluid samples obtained from women prior to the administration of hCG was (n = 4) 90 +/- 27 (mean +/- S.E.) pg/ml; in samples obtained 12 h after the hCG administration it was (n = 3) 135 +/- 23 pg/mL; in follicular fluids obtained 34 h after the hCG administration it was (n = 126) 322 +/- 46 pg/mL (P = 0.007 vs. pre-hCG). The mean ratio of follicular fluid/serum MCP-1 levels was 4.18. There was a correlation between follicular fluid MCP-1 levels and follicular fluid or serum progesterone levels (r = 0.21, P = 0.02; r = 0.29, P = 0.03, respectively). MCP-1 mRNA and the protein were expressed in ovarian stromal and granulosalutein cells in culture and were increased by interleukin-1 alpha and tumor necrosis factor-alpha in a time- and concentration-dependent manner. LH/hCG induced higher levels of MCP-1 mRNA expression and protein production in both cell cultures. We propose that regulation of MCP-1 in ovarian stromal and granulosa-lutein cells by cytokines may play a role in the physiology of periovulatory events.


Assuntos
Quimiocina CCL2/biossíntese , Folículo Ovariano/metabolismo , Ovário/metabolismo , Ovulação/imunologia , Adulto , Células Cultivadas , Quimiocina CCL2/imunologia , Feminino , Líquido Folicular/imunologia , Humanos , Células Lúteas/imunologia , Células Lúteas/metabolismo , Ovário/citologia , Ovário/imunologia , RNA Mensageiro/biossíntese , Células Estromais/imunologia , Células Estromais/metabolismo
17.
Obstet Gynecol ; 79(5 ( Pt 1)): 739-42, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1533022

RESUMO

Gonadotropin-releasing hormone agonists vary in structure and route of administration. We performed this study to compare patient response to intranasal nafarelin acetate versus subcutaneous leuprolide acetate as adjuncts to ovulation induction for in vitro fertilization (IVF). Forty-two patients entering their first cycle of IVF were randomized to receive either nafarelin acetate or leuprolide acetate. Patient characteristics in the two groups did not differ significantly, nor did cycle cancellation rates or outcome. There was no significant difference in patient response as indicated by follicular phase serum levels of estradiol (E2), FSH, or LH, luteal phase E2, and progesterone. Luteal phase progesterone-dependent endometrial protein was significantly lower in those taking nafarelin acetate, though it remained in the normal range. However, those receiving nafarelin acetate required significantly less human menopausal gonadotropin (hMG) and had significantly more embryos frozen for later transfer than those receiving leuprolide acetate. Intranasal nafarelin acetate can be used successfully in ovulation induction regimens that include GnRH agonists. The use of nafarelin acetate may decrease a patient's hMG requirement and increase the number of frozen embryos available for later transfer as compared with leuprolide acetate. Further studies are needed to optimize the dosing regimen.


Assuntos
Fertilização in vitro , Hormônio Liberador de Gonadotropina/análogos & derivados , Leuprolida/administração & dosagem , Indução da Ovulação/métodos , Administração Intranasal , Adulto , Feminino , Fase Folicular , Hormônio Liberador de Gonadotropina/administração & dosagem , Humanos , Injeções Subcutâneas , Fase Luteal , Nafarelina
18.
Obstet Gynecol ; 76(6): 1121-5, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1700350

RESUMO

As the surgical approach for ectopic pregnancies evolves from radical to conservative procedures, the potential hazard of persistent ectopic pregnancy has become increasingly pertinent. From September 1, 1986 to August 31, 1989, 11 women with persistent ectopic pregnancy after laparoscopic salpingostomy were diagnosed and treated at Yale-New Haven Hospital. Persistent ectopic pregnancy was suspected in nine cases because of symptoms and in two because of plateauing beta-hCG titers. Ten of 11 patients underwent repeat surgery. Eight had partial or complete salpingectomy of the involved ipsilateral tube, two had repeat salpingostomies, and one was treated with methotrexate. When the 11 women with persistent ectopic pregnancies were compared with 70 patients treated successfully by laparoscopic salpingostomy using multivariate stepwise logistic regression, smaller size of the ectopic (P less than .01) and fewer days of amenorrhea (P less than .05) predicted persistent ectopic pregnancy after laparoscopic salpingostomy. Based upon our experience, we believe that earlier-treated ectopic pregnancies (ie, fewer than 42 days of amenorrhea) and/or smaller ectopics (ie, 2.0 cm or less in diameter) require treatment with particular caution and close postoperative surveillance.


Assuntos
Laparoscopia/métodos , Gravidez Ectópica/cirurgia , Salpingostomia/métodos , Gonadotropina Coriônica/sangue , Gonadotropina Coriônica Humana Subunidade beta , Terapia Combinada , Esquema de Medicação , Feminino , Humanos , Metotrexato/uso terapêutico , Fragmentos de Peptídeos/sangue , Gravidez , Gravidez Ectópica/sangue , Gravidez Ectópica/diagnóstico , Recidiva , Análise de Regressão , Reoperação
19.
Science ; 226(4673): 433-4, 1984 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-17799934
20.
Brain Res ; 510(1): 84-91, 1990 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-1969760

RESUMO

Estrogen effects on tyrosine hydroxylase (TH), monoamine oxidase types A and B (MAO), and dopamine (DA) in microdissected regions of the hypothalamus, preoptic area and substantia nigra (SNR) of the female rat brain were investigated. Ovariectomized (OVX) young adult female rats were implanted with single silastic capsules containing 100% estradiol valerate (EV). Control rats received empty silastic capsules. Two weeks following capsule insertion, EV decreased TH activity and DA concentration in the arcuate nucleus (AN) while no significant changes in TH activity or DA concentration were observed in the SNR, ventromedial nucleus (VMN), suprachiasmatic nucleus, paraventricular nucleus, medial preoptic nucleus, or the periventricular preoptic nucleus. Although estrogen suppressed TH and DA in the AN, 2 weeks following removal of the estrogen containing capsules, TH activity and DA concentration were restored to control (OVX) levels. Suppression of MAO activity occurred in both the AN and the VMN of rats implanted with EV capsules and returned to OVX levels following the removal of the estradiol load. These results revealed that estrogen effects on TH and MAO activities and DA concentration in the midbrain are region specific and reversible; and that among the dopaminergic systems studied, estrogen effects on TH and DA are confined to the tuberoinfundibular dopaminergic system (TIDAS). Furthermore, these results support our hypothesis that estrogen is a key regulator of DA function in the TIDAS via effects on TH. The importance of these findings to the control of gonadotropin secretion and reproductive cyclicity is discussed.


Assuntos
Encéfalo/metabolismo , Dopamina/metabolismo , Estradiol/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Dopamina/fisiologia , Feminino , Monoaminoxidase/metabolismo , Ratos , Ratos Endogâmicos , Tirosina 3-Mono-Oxigenase/metabolismo
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