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2.
Andrology ; 5(1): 169-179, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27860455

RESUMO

Cyclic adenosine monophosphate (cAMP) plays a crucial role as a signaling molecule for capacitation, motility, and acrosome reaction in mammalian spermatozoa. It is well-known that cAMP degradation by phosphodiesterase (PDE) enzyme has a major impact on sperm functions. This study was undertaken to characterize cAMP-PDE activity in bovine spermatozoa. Total cAMP-PDE activity in cauda epididymal and ejaculated spermatozoa was 543.2 ± 49.5 and 1252.6 ± 86.5 fmoles/min/106 spermatozoa, respectively. Using different family-specific PDE inhibitors, we showed that in cauda epididymal and ejaculated spermatozoa, the major cAMP-PDE activity was papaverine-sensitive (44.5% and 57.5%, respectively, at 400 nm, papaverine is a specific inhibitor of the PDE10 family). These data are supporting the functional presence of PDE10 in bovine spermatozoa and were further confirmed by western blot to be PDE10A. Using immunocytochemistry, we showed immunoreactive signal for PDE10A present on the post-acrosomal region of the head and on the flagella of ejaculated spermatozoa. Using papaverine, we showed that it promotes tyrosine phosphorylation of sperm proteins, phosphorylation of Erk1 and Erk2, and Ca2+ release from Ca2+ store. These results suggest that PDE10 is functionally present in bovine spermatozoa and is affecting different molecular events involved in capacitation, most probably by cAMP local regulation.


Assuntos
Papaverina/farmacologia , Diester Fosfórico Hidrolases/metabolismo , Espermatozoides/enzimologia , Reação Acrossômica/efeitos dos fármacos , Animais , Cálcio/metabolismo , Bovinos , Epididimo/citologia , Epididimo/metabolismo , Masculino , Fosforilação , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Espermatozoides/efeitos dos fármacos
3.
Plant Sci ; 180(1): 99-110, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21421352

RESUMO

Cold hardening of winter wheat at 2 °C for 1-6 wks increased resistance to the snow mould pathogens LTB, Typhula incarnata, and Microdochium nivale as well as to powdery mildew (Blumaria graminis f. sp. graminis) and stripe rust (Puccinia striiformis). Using microarrays and hardening of winter wheat for 0.25, 0.5, 1, 7, 21 and 49 d, an upregulation of a wide range of stress-response genes that include defence-related and abiotic stress-related genes, transcription factors including several lipoxygenases and ethylene responsive factors, and WRKY genes was observed. For the majority of these genes, the upregulation occurred later in the 21-49 d hardening treatments and coincided with the highest expression levels of snow mould resistance. Defence-related sequences were upregulated to a greater extent and were more numerous in the snow mould resistant line CI14106 compared to cold hardy DH+268. Transcript profiling of candidate defence and other stress-related genes under prolonged conditions at -3 °C with or without snow mould infection showed that there was a decline in transcripts of the defence-related genes PR1.1b and NPR3 during the 12wks incubation. Additionally, 14 d hardening was insufficient to permit full expression of the jasmonic acid synthesis gene, allene oxide synthase (AOS) and the fructan degrading enzyme ß-fructofuranosidase compared the 42 d hardening treatment. The snow mould resistant line CI14106 was able to maintain higher transcript levels of AOS for longer conditions compared to the susceptible line Norstar under artificial snow mould conditions. These results explain the nature of cold-induced resistance to snow moulds and provide direction on establishing selection criteria for improving resistance and cold tolerance in winter wheat.


Assuntos
Temperatura Baixa , Triticum/fisiologia , Imunidade Inata/genética , Imunidade Inata/fisiologia , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase , Triticum/genética
4.
HIV Med ; 7(1): 32-7, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16313290

RESUMO

OBJECTIVES: Despite the benefits of HAART, initiation of antiretroviral therapy in HIV-HCV co-infected patients is often delayed as a consequence of patient and physician concern pertaining to liver toxicity. It is unclear whether this is justified. METHODS: We retrospectively evaluated treatment duration and outcome in 186 patients initiating a first HAART regimen. RESULTS: Despite frequent HIV RNA suppression and CD4 T-cell increase following initiation of HAART, the median duration of therapy was only 8 months. Therapy was discontinued primarily for gastrointestinal intolerance (26%), poor adherence (19%), neurocognitive side effects (13%), and substance abuse (6%). Regimes were changed to reduce pill burden and/or frequency of dosing as well (11%). Only six (4%) subjects interrupted therapy as a result of clinically apparent liver toxicity. None were on low dose ritonavir-containing therapy. In those subjects remaining on HAART for at least 12 months, the median ALT level increased marginally from a baseline of 44 IU/mL to 56 IU/mL. The median AST was 44 IU/mL at baseline and at month 12. CONCLUSIONS: These results support our contention that regimen potency, durability, and extrahepatic side effect profile should remain the paramount considerations related to the selection of HAART regimen in HIV-HCV co-infection.


Assuntos
Terapia Antirretroviral de Alta Atividade/efeitos adversos , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Hepatite C Crônica/complicações , Adulto , Alanina Transaminase/sangue , Fármacos Anti-HIV/efeitos adversos , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Contagem de Linfócito CD4 , Doença Hepática Induzida por Substâncias e Drogas , Esquema de Medicação , Feminino , Gastroenteropatias/induzido quimicamente , Infecções por HIV/imunologia , Hepatite C Crônica/enzimologia , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Estudos Retrospectivos , Resultado do Tratamento , Carga Viral
5.
Genome ; 48(1): 97-107, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15729401

RESUMO

An F4-derived F6 recombinant inbred line population (n = 148) of a cross between the durable stripe (yellow) rust (caused by Puccinia striiformis) and leaf (brown) rust (caused by Puccinia triticina) resistant cultivar, Triticum aestivum 'Cook', and susceptible genotype Avocet-YrA was phenotyped at several locations in Canada and Mexico under artificial epidemics of leaf or stripe rusts and genotyped using amplified fragment length polymorphism (AFLP) and microsatellite markers. Durable adult plant resistance to stripe and leaf rusts in 'Cook' is inherited quantitatively and was based on the additive interaction of linked and (or) pleiotropic slow-rusting genes Lr34 and Yr18 and the temperature-sensitive stripe rust resistance gene, YrCK, with additional genetic factors. Identified QTLs accounted for 18% to 31% of the phenotypic variation in leaf and stripe rust reactions, respectively. In accordance with the high phenotypic associations between leaf and stripe rust resistance, some of the identified QTLs appeared to be linked and (or) pleiotropic for both rusts across tests. Although a QTL was identified on chromosome 7D with significant effects on both rusts at some testing locations, it was not possible to refine the location of Lr34 or Yr18 because of the scarcity of markers in this region. The temperature-sensitive stripe rust resistance response, conditioned by the YrCK gene, significantly contributed to overall resistance to both rusts, indicating that this gene also had pleiotropic effects.


Assuntos
Basidiomycota/fisiologia , Genes de Plantas/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Locos de Características Quantitativas , Triticum/genética , Triticum/microbiologia , Mapeamento Cromossômico , Fenótipo , Folhas de Planta/microbiologia , Polimorfismo de Fragmento de Restrição
6.
Genome ; 46(1): 135-45, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12669806

RESUMO

Thinopyrum intermedium (2n = 6x = 42, JJJsJsSS) is potentially a useful source of resistance to wheat streak mosaic virus (WSMV) and its vector, the wheat curl mite (WCM). Five partial amphiploids, namely Zhong 1, Zhong 2, Zhong 3, Zhong 4, and Zhong 5, derived from Triticum aestivum x Thinopyrum intermedium crosses produced in China, were screened for WSMV and WCM resistance. Zhong 1 and Zhong 2 had high levels of resistance to WSMV and WCM. The other three partial amphiploids, Zhong 3, 4, and 5, were resistant to WSMV, but were susceptible to WCM. Genomic in situ hybridization (GISH) using a genomic DNA probe from Pseudoroegneria strigosa (SS, 2n = 14) demonstrated that two partial amphiploids, Zhong 1 and Zhong 2, have almost the identical 10 Th. intermedium chromosomes, including four Js, four J, and two S genome chromosomes. Both of them carry two pairs of J and a pair of Js genome chromosomes and two different translocations that were not observed in the other three Zhong lines. The partial amphiploids Zhong 3, 4, and 5 have another type of basic genomic composition, which is similar to a reconstituted alien genome consisting of four S and four Js genome chromosomes of Th. intermedium (Zhong 5 has two Js chromosomes plus two Js-W translocations) with six translocated chromosomes between S and Js or J genomes. All three lines carry a specific S-S-Js translocated chromosome, which might confer resistance to barley yellow dwarf virus (BYDV-PAV). The present study identified a specific Js2 chromosome present in all five of the Zhong lines, confirming that a Js chromosome carries WSMV resistance. Resistance to WCM may be linked with J or Js chromosomes. The discovery of high levels of resistance to both WSMV and WCM in Zhong 1 and Zhong 2 offers a useful source of resistance to both the virus and its vector for wheat breeding programs.


Assuntos
Agropyron/virologia , Ácaros/virologia , Potyviridae/patogenicidade , Triticum/virologia , Agropyron/genética , Animais , Cromossomos , Hibridização Genética , Triticum/genética
7.
Theor Appl Genet ; 104(2-3): 315-320, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12582703

RESUMO

Stripe rust resistance was identified in Triticum vavilovii( T. vaviloviiAus22498)-derived Russian wheat aphid (RWA)-resistant germplasm. Inheritance studies indicated monogenic control of resistance. The resistance gene was tentatively designated as Yrvav and was located on chromosome 1B by monosomic analysis. A close association (1.5+/-0.9% recombination) of Yrvav with a T. vavilovii-derived gliadin allele ( Gli-B1vav) placed it in chromosome arm 1BS. Yrvavwas allelic with Yr10. Tests with Yr10 avirulent and virulent pathotypes showed that Yrvav and Yr10 possess identical pathogenic specificity. Yrvav and Yr10 showed close genetic associations with alternate alleles at the Xpsp3000(microsatellite marker), Gli-B1 and Rg1 loci. Based on these observations Yrvav was named as Yr10vav. The close association between Xpsp3000 and Gli-B1 was also confirmed. The Yr10vav-linked Xpsp3000 allele (285 bp) was not present in 65 Australian cultivars, whereas seven Australian wheats lacking Yr10 carried the same Xpsp3000 allele (260 bp) as Yr10carrying wheat cultivar Moro. Xpsp3000 and/or Gli-B1 could be used in marker-assisted selection for pyramiding Yr10vavor Yr10 with other stripe rust resistance genes. Yr10vav was inherited independently of the T. vavilovii-derived RWA resistance.

8.
Plant Dis ; 86(4): 423-428, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30818719

RESUMO

Wheat curl mite (WCM), Aceria tosichella, is the vector of Wheat streak mosaic virus (WSMV), a destructive viral pathogen in wheat (Triticum aestivum). Genetic resistance to WCM colonization can reduce the incidence of wheat streak mosaic. Chromosome 6V in Hay-naldia villosa is a new source of WCM resistance. We compared variation in resistance among different sources of H. villosa chromosome 6V and 6VS lines to WCM and WSMV and their effectiveness in controlling the incidence of WSMV following exposure to viruliferous WCM. WCM resistance varied among the 6V and 6VS lines depending on the H. villosa parent. The 6V substitution lines Yi80928, GN21, and GN22 derived from an accession of H. villosa from China, and the 6VS translocation lines 92R137, 92R178, and Sub6V from an H. villosa accession collected from the United Kingdom were uniformly resistant to WCM colonization. In contrast, the 6V substitution line RW15 and a 6VS translocation line Pm33 developed from an H. villosa collection from the former Union of Soviet Socialist Republics were susceptible to WCM. All 6V and 6VS lines were susceptible to WSMV when manually inoculated. However, symptom expression was delayed in the WCM-resistant 6V and 6VS lines after exposure to viruliferous WCM. The 6V and 6VS lines differed in their ability to control WSMV infection. WCM-susceptible lines RW15 and Pm33 had no effect on controlling the infection by WSMV. Lines GN21 and GN22 were the most effective of the three H. villosa sources in limiting the spread of WSMV. Their high yield potential and protein content, in combination with resistance to stripe rust (Puccinia striiformis f. sp. tritici) and powdery mildew (Erysiphe graminis f. sp. tritici), make GN21 and GN22 promising sources of WCM resistance.

10.
Comp Biochem Physiol B Biochem Mol Biol ; 130(1): 105-15, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11470449

RESUMO

The activity of the triacylglycerol bioassembly enzyme, diacylglycerol acyltransferase (DGAT), was characterized in microsomal fractions prepared from bovine subcutaneous (SC) adipose, intramuscular (IM) adipose, and muscle (pars costalis diaphragmatis) tissue. The activity of DGAT was generally higher from SC adipose tissue than from IM adipose or muscle tissue. The characteristics of DGAT activity from the three bovine tissues resembled the activity characteristics observed in previous studies from various other organisms and tissues; the pH optimum was near neutrality, the activity was almost completely inhibited by pre-incubation with N-ethylmaleimide (NEM), and the enzyme accepted a broad range of acyl-CoAs and sn-1,2-diacylglycerols. In some aspects, the SC adipose tissue DGAT activity was different from the DGAT activity from the other two tissues. The SC adipose tissue DGAT activity was not as susceptible to inhibition by NEM as the enzymes from the two other tissue sources, and it exhibited increased specificity for substrates containing oleoyl moieties. The differences in DGAT properties between the three bovine tissues may account to some extent for the differences in the relative fatty acid composition and the positional distribution of fatty acids in triacylglycerol between bovine tissues. The observed differences in enzymatic properties also support recent biochemical and molecular genetic observations that imply the existence of multiple DGAT genes and/or isoforms.


Assuntos
Aciltransferases/química , Tecido Adiposo/enzimologia , Microssomos/enzimologia , Músculos/enzimologia , Acil Coenzima A/metabolismo , Animais , Bovinos , Cromatografia em Camada Fina , Diacilglicerol O-Aciltransferase , Diglicerídeos/metabolismo , Relação Dose-Resposta a Droga , Etilmaleimida/farmacologia , Concentração de Íons de Hidrogênio , Isoformas de Proteínas , Especificidade por Substrato , Fatores de Tempo , Distribuição Tecidual
11.
FEBS Lett ; 481(2): 189-92, 2000 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-10996321

RESUMO

Diacylglycerol acyltransferase has a universal role in catalyzing the acyl-CoA-dependent formation of triacylglycerol in microorganisms, animals and plants. Acylation stimulating protein, from human blood, is known to enhance diacylglycerol acyltransferase activity and triacylglycerol biosynthesis in human adipocytes. In the current study, acylation stimulating protein was also shown to enhance diacylglycerol acyltransferase activity in microsomes from cell suspension cultures of oilseed rape. Enzyme stimulation occurred over the pH range of 6-9 but the degree of stimulation decreased with increasing ionic strength at pH 7.4. Varying acyl-CoA concentration did not affect the degree of stimulation. Membranes from triacylglycerol producing cells in plants and humans may have similar binding sites for acylation stimulating protein which have been preserved during molecular evolution. The results suggest that human acylation stimulating protein may be useful in modifying lipid biosynthesis in plants.


Assuntos
Aciltransferases/metabolismo , Proteínas Sanguíneas/farmacologia , Brassica/citologia , Complemento C3a/análogos & derivados , Microssomos/efeitos dos fármacos , Triglicerídeos/biossíntese , Acil Coenzima A/metabolismo , Acil Coenzima A/farmacologia , Brassica/efeitos dos fármacos , Brassica/enzimologia , Catálise/efeitos dos fármacos , Técnicas de Cultura de Células/métodos , Células Cultivadas , Diacilglicerol O-Aciltransferase , Relação Dose-Resposta a Droga , Evolução Molecular , Humanos , Concentração de Íons de Hidrogênio , Cinética , Microssomos/enzimologia , Microssomos/metabolismo , Concentração Osmolar , Cloreto de Potássio/farmacologia
12.
Genome ; 43(4): 712-9, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10984185

RESUMO

A combination of genomic in situ hybridization (GISH) and meiotic pairing analysis of wheat-Thinopyrum partial amphiploids was employed to identify the genomic constitution and relationships between partial amphiploids derived from wheat and wheatgrass crosses. On the basis of similarities in the meiotic behavior and GISH patterns, the alien chromosomes of two of eight partial amphiploids, TAF46 and 'Otrastayuskaya 38', were judged to originate from Th. intermedium, whereas Th. ponticum was one of the parents of the other six partial amphiploids; PWM706, PWM206, PWM209, PWMIII, OK7211542, and Ag-wheat hybrid. Each of these partial amphiploids was found to contain a synthetic alien genome composed of different combinations of St-, J-, or Js-genome chromosomes. For relatedness of partial amphiploid lines, meiotic analysis of F1 hybrids and GISH results were generally complementary, but the latter offered greater precision in identifying constituent genomes.


Assuntos
Genes de Plantas , Hibridização In Situ , Meiose , Triticum/genética , Southern Blotting , Cromossomos/ultraestrutura , Cruzamentos Genéticos , Temperatura
13.
Genome ; 43(2): 217-23, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10791808

RESUMO

In western Canada, the Bt-10 resistance gene in wheat (Triticum aestivum) is effective against all the known races of common bunt caused by Tilletia tritici and T laevis. The genotypes of 199 F2 plants, originated from a cross between BW553 containing Bt-10 and the susceptible spring wheat cultivar 'Neepawa,' were established in greenhouse and field inoculation studies. A ratio of 1:2:1 resistant : heterozygous : susceptible was observed for bunt reaction, indicating that Bt-10 was expressed in a partially dominant fashion. A polymorphic DNA fragment, amplified using RAPD, and previously shown to be linked to Bt-10 was sequenced and SCAR (sequence characterized amplified region) primers devised. However, SCAR primers failed to amplify the polymorphic fragment. Restriction of PCR products with DraI revealed a polymorphic fragment of 490 bp resulting from a single base pair difference between lines possessing Bt-10 and those lacking the gene. As per the base pair difference, FSD and RSA primers were designed to generate a 275-bp polymorphic DNA fragment. Both 275- and 490-bp polymorphic fragments were present in all of the 22 cultivars known to carry Bt-10, and absent in all 16 cultivars lacking Bt-10. A 3:1 ratio was observed for presence: absence of the 275-bp marker in the F2 population. Using Southern analysis, the 490-bp fragment was effective in differentiating homozygous resistant plants from those heterozygous for Bt-10, based on its presence and the hybridization signal strength. A 1:2:1 resistant : heterozygous : susceptible ratio was also observed for the molecular marker and corresponded to 88% of the phenotypes deduced from the original F2 population. The molecular marker was estimated to be between 1.1 cM and 6.5 cM away from the Bt-10 resistance gene, based on the segregation analysis. Segregation analyses of Bt-10 and the 275-bp marker, evaluated in three different Canada Prairie Spring (CPS) wheat populations, demonstrated a segregation ratio of 3:1 for the molecular marker in two of the populations. These results demonstrated that the PCR marker system using the FSD and RSA primer pair permitted a rapid and reliable identification of individual lines carrying the Bt-10 gene for resistance to common bunt.


Assuntos
Genes de Plantas , Marcadores Genéticos , Doenças das Plantas/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Triticum/genética , Southern Blotting , Clonagem Molecular , Genótipo , Imunidade Inata/genética , Polimorfismo Genético , Polimorfismo de Fragmento de Restrição , Recombinação Genética
14.
Genetics ; 155(1): 361-7, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10790409

RESUMO

A detailed RFLP map was constructed of the distal end of the short arm of chromosome 1D of Aegilops tauschii, the diploid D-genome donor species of hexaploid wheat. Ae. tauschii was used to overcome some of the limitations commonly associated with molecular studies of wheat such as low levels of DNA polymorphism. Detection of multiple loci by most RFLP probes suggests that gene duplication events have occurred throughout this chromosomal region. Large DNA fragments isolated from a BAC library of Ae. tauschii were used to determine the relationship between physical and genetic distance at seed storage protein loci located at the distal end of chromosome 1DS. Highly recombinogenic regions were identified where the ratio of physical to genetic distance was estimated to be <20 kb/cM. These results are discussed in relation to the genome-wide estimate of the relationship between physical and genetic distance.


Assuntos
Proteínas de Plantas/genética , Triticum/genética , Mapeamento Cromossômico , Polimorfismo de Fragmento de Restrição , Sementes
15.
Biochem Soc Trans ; 28(6): 684-6, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11171170

RESUMO

The expression of diacylglycerol acyltransferase (DGAT, EC 2.3.1.20) with predicted molecular mass of 56.9. kDa (BnDGAT1) was examined using microspore-derived cell suspension cultures of oilseed rape (Brassica napus L. cv Jet Neuf). As well, a recombinant histidine-tagged N-terminal fragment of BnDGAT1 [BnDGAT1((1-116))His(6)], which was relatively hydrophilic, was partially characterized. A temporal increase in DGAT activity occurred within a 24 h period following transfer of cells from 6% (w/v) sucrose to 14% (w/v) sucrose. Western blotting indicated that the abundance of BnDGAT1 protein was closely correlated with DGAT activity. BnDGAT1 mRNA also exhibited a temporal increase within the 24 h period following transfer of cells into higher sucrose concentrations, but the transcript level was not closely associated with DGAT activity as BnDGAT1 protein. The fragment BnDGAT1(1-116)His(6) interacted with [1-(14)C]oleoyl-CoA, suggesting that the N-terminal region of BnDGAT1 may have a role in binding cellular acyl-CoA.


Assuntos
Aciltransferases/genética , Aciltransferases/metabolismo , Brassica/enzimologia , Acil Coenzima A/metabolismo , Brassica/citologia , Células Cultivadas , Diacilglicerol O-Aciltransferase , Cinética , Biossíntese de Proteínas , Proteínas Recombinantes/metabolismo , Especificidade por Substrato , Fatores de Tempo , Transcrição Gênica
16.
Lipids ; 34(11): 1143-9, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10606036

RESUMO

Several factors, including an unidentified endogenous component, were found to stimulate microsomal diacylglycerol acyltransferase (DGAT, EC 2.3.1.20) from a microspore-derived cell-suspension culture of oilseed rape (Brassica napus L. cv. Jet Neuf). At a concentration of 25 mM, MgSO4 and MgCl2 stimulated microsomal DGAT 25- and 10-fold, respectively. ATP and CoA at concentrations of 2 and 1 mM stimulated the enzyme 2.4- and 12-fold, respectively, although the effects were lessened in the presence of higher Mg2+ concentrations. Although microsomal DGAT activity was increased only slightly by the addition of exogenous sn-1,2-diacylglycerol to the reaction mixture, it was increased substantially by the addition of exogenous phosphatidate. sn-Glycerol-3-phosphate and other phospholipids tested did not have this stimulatory effect. DGAT activity did not decrease when microsomes were incubated with ATP in the presence of the cytosolic fraction. This fraction, however, contained a small organic compound(s) that stimulated microsomal DGAT activity.


Assuntos
Aciltransferases/metabolismo , Brassica/enzimologia , Microssomos/enzimologia , Trifosfato de Adenosina/farmacologia , Brassica/ultraestrutura , Células Cultivadas , Coenzima A/farmacologia , Citosol/metabolismo , Diacilglicerol O-Aciltransferase , Diglicerídeos/farmacologia , Cloreto de Magnésio/farmacologia , Sulfato de Magnésio/farmacologia , Fosfolipídeos/farmacologia , Fosforilação
17.
J Anim Sci ; 77(7): 1717-25, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10438017

RESUMO

The deposition of i.m. fat, or marbling, in cattle is recognized as a desirable carcass trait in North American beef grading schemes. In order to investigate the relationship between degree of marbling and fatty acid composition of whole bovine muscle, we extracted the total lipid from pars costalis diaphragmatis (PCD) (n = 23) and longissimus (n = 36) muscles from Wagyu crossbred cattle that were assigned Canadian Grading Agency marbling scores ranging from 1 to 8 on an inverse 10-point scale (i.e., a score of 1 indicated "very abundant" marbling and a score of 10 would be assigned to a carcass "devoid" of marbling). Fatty acid methyl esters (FAME) of the total lipid and triacylglycerol fractions were resolved and quantified through GLC. Marbling scores were negatively associated with total lipid from both PCD (r = -.57, P < .01) and longissimus (r = -.80, P < .001). Differences between PCD and longissimus were found for almost all FAME studied from both lipid fractions, but no differences (P > .05) were seen when the monounsaturated:saturated fatty acid (MUFA/SFA) ratios were compared. Heifers had higher (P < .05) oleic acid content and lower (P < .05) palmitic acid content in lipid extracted from both muscles, resulting in higher (P < .05) MUFA/SFA ratios than those for steers. The relative amount of myristic acid increased as the lipid content (total lipid and triacylglycerol) increased in either longissimus (r values from .48 to .55; n = 36; P < .01) or PCD muscles (r from .67 to .76; n = 23; P < .001). The relative amount of linoleic acid (cis-9, cis-12 isomer) from total lipid was negatively associated with all chemical measurements of lipid from the longissimus (r from -.52 to -.64; n = 36; P < .001) and PCD muscles (r from -.75 to -.85; n = 23; P < .001). This association was not significant (P > .1) for either muscle when linoleic acid from the triacylglycerol fraction was examined, suggesting the negative association between this fatty acid and lipid content was due to a dilution of membrane phospholipids with increasing triacylglycerol. Indices of fatty acid elongase activity, calculated from FAME data, implicated the balance between this enzyme activity and fatty acid synthase as a source of variation between animals displaying various degrees of marbling and worthy of further investigation to better understand the process of marbling fat deposition in beef cattle.


Assuntos
Tecido Adiposo/anatomia & histologia , Bovinos/anatomia & histologia , Ácidos Graxos/química , Tecido Adiposo/química , Animais , Cruzamento , Feminino , Lipídeos/química , Masculino , Carne/normas , Fatores Sexuais
18.
Genome ; 42(6): 1217-23, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10659790

RESUMO

The genomic origin of alien chromosomes present in a wheat-Thinopyrum intermedium partial amphiploid TAF46 (2n = 8x = 56) and six derived chromosome addition lines were analyzed by genomic in situ hybridization (GISH) using S genomic DNA from Pseudoroegneria strigosa (2n = 2x = 14, SS) as a probe. The GISH analysis clearly showed that the chromosome complement of the partial amphiploid TAF46 consists of an entire wheat genome plus one synthetic genome consisting of a mixture of six S genome chromosomes and eight J (=E) genome chromosomes derived from Th. intermedium (2n = 6x = 42, JJJ(s)J(s)SS). There were no Js genome chromosomes present in TAF46. The J genome chromosomes present in TAF46 displayed a unique GISH hybridization pattern with the S genomic DNA probe, in which S genome DNA strongly hybridized at the terminal regions and weakly hybridized over the remaining parts of the chromosomes. This provides a diagnostic marker for distinguishing J genome chromosomes from Js or S genome or wheat ABD genome chromosomes. The genomic origin of the alien chromosomes present in the six derived chromosome addition lines were identified by their characteristic GISH hybridization patterns with S genomic DNA probe. GISH analysis showed that addition lines L1, L2, L3, and L5 carried one pair of J genome chromosomes, while addition lines L4 and L7 each carried one pair of S genome chromosomes. GISH patterns detected by the S genome probe on addition line of L1 were identical to those of the J genome chromosomes present in the partial amphiploid TAF46, suggesting that these chromosomes were not structurally altered when they were transferred from TAF46 to addition lines.

19.
J Fr Ophtalmol ; 21(7): 484-94, 1998.
Artigo em Francês | MEDLINE | ID: mdl-9805683

RESUMO

PURPOSE: Optical Coherence Tomography (OCT) is a novel noninvasive and noncontact imaging technique providing cross-sectional representations of the eye structures. OCT is analogous to Ultrasound B-scan, except that it analyzes the reflection of a 850 nm light wave. The aim of this study was to assess the potential of ocular coherence tomography for diagnosing and monitoring macular diseases. METHODS: Cross-sectional images were performed with the Zeiss-Humphrey OCT. Over one year period, we examined approximately 300 patients with idiopathic full thickness macular hole, lamellar hole, cystoid macular edema, choroidal new vessels, epiretinal membrane, diabetic maculopathy, and central serous chorioretinopathy. RESULTS: OCT can provide new information concerning the posterior pole diseases mentioned above. OCT can also be useful in thickness measurements. CONCLUSION: OCT allows tomographic analysis of macular diseases. The information obtained is different from that obtained by histologic study which is sometimes hard to interprete. OCT is mostly useful in studying internal layers of the retina. Further applications may be developed.


Assuntos
Doenças da Coroide/diagnóstico , Macula Lutea/patologia , Doenças Retinianas/diagnóstico , Tomografia/instrumentação , Desenho de Equipamento , Angiofluoresceinografia , Humanos , Sensibilidade e Especificidade
20.
Genome ; 41(4): 580-6, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9796107

RESUMO

Genomic in situ hybridization (GISH) using genomic DNA probes from Thinopyrum elongatum (Host) D.R. Dewey (genome E, 2n = 14), Thinopyrum bessarabicum (Savul. & Rayss) A. Löve (genome J, 2n = 14), and Pseudoroegneria strigosa (M. Bieb.) A. Löve (genome S, 2n = 14), was used to examine the genomic constitution of Thinopyrum intermedium (Host) Barkworth & D.R. Dewey (2n = 6x = 42) and Thinopyrum ponticum (Podp.) Barkworth & D.R. Dewey (2n = 10x = 70). Evidence from GISH indicated that hexaploid Th, intermedium contained the J, Js, and S genomes, in which the J genome was related to the E genome of Th. elongatum and the J genome of Th. bessarabicum. The S genome was homologous to the S genome of Ps. strigosa, while the Js genome referred to modified J- or E-type chromosomes distinguished by the presence of S genome specific sequences close to the centromere. Decaploid Th. ponticum had only the two basic genomes J and Js. The Js genome present in Th. intermedium and Th. ponticum was homologous with E or J genomes, but was quite distinct at centromeric regions, which can strongly hybridize with the S genome DNA probe. Based on GISH results, the genomic formula of Th. intermedium was redesignated JJsS and that of Th. ponticum was redesignated JJJJsJs. The finding of a close relationship among S, J, and Js genomes provides valuable markers for molecular cytogenetic analyses using S genome DNA probes to monitor the transfer of useful traits from Th. intermedium and Th. ponticum to wheat.


Assuntos
Grão Comestível/genética , Genoma de Planta , Centrômero/genética , Sondas de DNA , Geografia , Hibridização In Situ/métodos , Cariotipagem , Raízes de Plantas
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