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1.
J Dairy Sci ; 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38395402

RESUMO

Objectives were to evaluate the effects of a multistrain Bacillus-based (Bacillus subtilis and Bacillus pumilus blend) direct-fed microbial (DFM) on production, metabolism, inflammation biomarkers and gastrointestinal tract (GIT) permeability during and following feed restriction (FR) in mid-lactation Holstein cows. Multiparous cows (n = 36; 138 ± 53 DIM) were randomly assigned to 1 of 3 dietary treatments: 1) control (CON; 7.5 g/d rice hulls; n = 12), 2) DFM10 (10 g/d Bacillus DFM, 4.9 × 109 cfu/d; n = 12) or 3) DFM15 (15 g/d Bacillus DFM, 7.4 × 109 cfu/d; n = 12). Before study initiation, cows were fed their respective treatments for 32 d. Cows continued to receive treatments during the trial, which consisted of 3 experimental periods (P): P1 (5 d) served as baseline for P2 (5 d), during which all cows were restricted to 40% of P1 dry matter intake (DMI), and P3 (5 d), a "recovery" where cows were fed ad libitum. On d 4 of P1 and on d 2 and 5 of P2, GIT permeability was evaluated in vivo using the oral paracellular marker chromium (Cr)-EDTA. As anticipated, FR decreased milk production, decreased insulin, glucagon, and BUN but increased nonesterified fatty acids. During recovery, DMI rapidly increased on d 1 then subsequently decreased (4.9 kg) on d 2 before returning to baseline whereas milk yield slowly increased but remained decreased (13%) relative to P1. DFM10-fed cows had increased DMI and milk yield relative to DFM15 during P3 (10%). Overall, milk lactose content was increased in DFM cows relative to CON (0.10 percentage units), and DFM10 cows tended to have increased lactose yield relative to CON and DFM15 during P3 (8 and 10%, respectively). No overall treatment differences were observed for other milk composition variables. Circulating glucose was quadratically increased in DFM10 cows compared with CON and DFM15 during FR and recovery. Plasma Cr area under the curve was increased in all cows on d 2 (9%) and 5 (6%) relative to P1. Circulating lipopolysaccharide binding protein (LBP), serum amyloid A (SAA), and haptoglobin (Hp) increased in all cows during P2 compared with baseline (31%, 100%, and 9.0-fold, respectively). Circulating Hp concentrations continued to increase during P3 (274%). Overall, circulating LBP and Hp tended to be increased in DFM15 cows relative to DFM10 (29 and 81%, respectively), but no treatment differences were observed for SAA. Following feed reintroduction during P3, fecal pH initially decreased (0.62 units), but returned to baseline levels whereas fecal starch markedly increased (2.5-fold) and remained increased (82%). Absolute quantities of a fecal Butyryl-CoA CoA transferase (But) gene associated with butyrate synthesis, collected by fecal swab were increased in DFM10 cows compared with CON and DFM15-fed cows. In summary, FR increased GIT permeability, caused inflammation, and decreased production. Feeding DFM10 increased some key production and metabolism variables and upregulated a molecular biomarker of microbial hindgut butyrate synthesis, while DFM15 appeared to augment immune activation.

2.
Eur Psychiatry ; 61: 41-48, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31288209

RESUMO

AIM: Attention Deficit Hyperactivity Disorder (ADHD) is a lifespan disorder associated with considerable economic cost. While the economic burden of ADHD has been widely estimated, there is considerable variation in reported costs between studies, which typically focus on health outcomes only, lack adequate control and fail to correct for the influence of genetic and shared environmental factors. The aim of this study is to overcome these limitations to reach a fuller understanding of the economic burden of ADHD. METHOD: Using the Danish National Registers 5269 adults with a diagnosis of ADHD in adulthood who had not received a diagnosis in childhood were identified. Excluding cases with missing data, comorbid diagnoses, and cases without a same sex sibling free of any diagnosed psychiatric diagnoses, a final cohort was formed consisting of 460 sibling dyads. Using a cross-sectional method focusing on the year 2010, cost differences between each adult with ADHD and their sibling were calculated from data retrieved from health, education, crime, employment and social care registers. RESULTS: Adults with ADHD had considerably lower disposable income and paid less tax than their siblings. They also received more state benefits, had higher costs for health, social care, and crime than their siblings. The total average costs difference for the year 2010 was 20,134 euros more than their sibling for each adult with ADHD. CONCLUSION: ADHD is associated with considerable costs which are borne by both the individual and the state and underlines the need to consider the wider economic impact of ADHD beyond income and healthcare utilisation costs.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/economia , Efeitos Psicossociais da Doença , Irmãos , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Comorbidade , Estudos Transversais , Emprego/estatística & dados numéricos , Feminino , Humanos , Renda , Seguro Saúde/estatística & dados numéricos , Masculino , Qualidade de Vida , Comportamento Social , Fatores Socioeconômicos , Adulto Jovem
3.
J Parasitol ; 83(5): 785-91, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9379279

RESUMO

It is widely assumed that barren Strongyloides stercoralis occurring in chronically infected carriers can become fecund when immunity wanes. Evidence for this involves corticosteroid treatment of hosts harboring occult infections that subsequently return to patency. However, nematodes have ecdysteroid receptors, and it has been suggested that corticosteroids act directly on the parasite, inducing autoinfective development, rather than indirectly by suppressing host immunity. To test these competing concepts, barren females were recovered from donor dogs when the dogs' fecal examinations turned negative. Groups of 100 active barren worms were surgically transplanted into the small intestines of each of 6 naive canine recipients. Three were examined at necropsy at 4-5 days postinfection (PI), before autoinfection could amplify the number of successfully transferred parasites. The remaining recipients were examined 21-22 days PI when, if autoinfection had occurred, the worm populations should have increased. At 4-5 days, gravid worms occurred in each of the recipients (19 +/- 6 worms/dog). By 21-22 days, a remarkable population increase had occurred (522.6 +/- 296 worms/dog). Worms from chronically infected donors were stunted, and electron microscopy revealed damage to the intestine and ovaries. Successfully transplanted worms recovered at days 4-5 PI were ovigerous and less stunted and showed repair of intestinal and ovarian tissues.


Assuntos
Enteropatias Parasitárias/parasitologia , Strongyloides stercoralis/fisiologia , Estrongiloidíase/parasitologia , Animais , Doença Crônica , Cães , Fezes/parasitologia , Feminino , Fertilidade , Enteropatias Parasitárias/imunologia , Intestinos/parasitologia , Intestinos/patologia , Intestinos/ultraestrutura , Larva/fisiologia , Masculino , Ovário/patologia , Ovário/ultraestrutura , Strongyloides stercoralis/imunologia , Strongyloides stercoralis/ultraestrutura , Estrongiloidíase/imunologia
4.
J Immunol ; 153(1): 205-11, 1994 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-8207236

RESUMO

A significant reduction in challenge worm survival occurred when BALB/cBYJ mice were vaccinated against Onchocerca volvulus infective third stage larvae (L3) by using irradiated O. volvulus L3. Challenge infections consisted of L3 implanted in diffusion chambers, which were used as a means to contain, and thus efficiently recover, the larvae from the host. The goal of the present study was to describe the mechanism of immune-mediated killing of O. volvulus L3 in diffusion chambers in mice. Direct contact between host cells and parasites was required for killing of larvae in immunized hosts. To define the mechanism of immune-mediated killing in this system, the time of influx of cells and cytokines into the infection site was compared with the time challenge infections were killed. The only cell type that was found to increase in diffusion chambers in immunized mice was eosinophils; maximal levels of eosinophils were coincident with the time of parasite killing. IL-5 was found in diffusion chambers of immunized mice coincident with the time of parasite killing; IL-5 was not found in diffusion chambers recovered from control mice. Significant levels of IFN-gamma were absent in the diffusion chambers of both groups. Immunized mice were treated with mAb to eliminate IL-5 or IL-4 to assess the role these cytokines or their by-products play in larval killing. Elimination of either IL-5 or IL-4 significantly reduced the protective effects of vaccination against larval O. volvulus.


Assuntos
Interleucina-4/imunologia , Interleucina-5/imunologia , Onchocerca volvulus/imunologia , Oncocercose/imunologia , Animais , Citotoxicidade Imunológica , Imunidade Celular , Imunização , Larva , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Linfócitos T Auxiliares-Indutores/imunologia
5.
Am J Trop Med Hyg ; 49(6): 783-8, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8279644

RESUMO

BALB/cBYJ mice were immunized against larval Onchocerca volvulus by subcutaneous injection of normal, irradiated, or freeze-thaw-killed Onchocerca sp. larvae. The mice received challenge infections of O. volvulus third-stage larva (L3) contained in diffusion chambers implanted subcutaneously. At two-weeks postinfection, the diffusion chambers were removed and larval survival was assessed. When mice were immunized a single time with 35-krad-irradiated or normal O. volvulus L3, there was a significant reduction in the survival of challenge parasites. However, there was little or no reduction in challenge worm survival when mice were immunized a single time with freeze-thaw-killed O. volvulus L3 or fourth-stage larva (L4), or irradiated O. lienalis L3. When a second dose of freeze-thaw killed O. volvulus L3 or irradiated O. lienalis L3 was administered, there was a significant reduction in parasite survival in immunized mice. Immunization with O. volvulus L4 or a combination of L3 and L4 failed to confer protection. These results demonstrate that mice can be immunized against larval O. volvulus and that diffusion chambers are an efficient method for studying protective immunity to this parasite in a mouse model.


Assuntos
Onchocerca volvulus/imunologia , Oncocercose/prevenção & controle , Animais , Cultura em Câmaras de Difusão , Modelos Animais de Doenças , Imunização , Imunização Secundária , Injeções Subcutâneas , Larva/imunologia , Larva/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Onchocerca volvulus/efeitos da radiação , Oncocercose/imunologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologia
6.
J Parasitol ; 79(4): 571-82, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8331478

RESUMO

Third-stage larvae (L3) of Onchocerca volvulus were implanted in diffusion chambers in chimpanzees, mangabey monkeys, rhesus monkeys, squirrel monkeys, and inbred strains of mice, jirds, and rats for 3-63 days. At different times during the experimental period, larvae were recovered and assessed for their viability and development. Survival and growth rates were equal regardless of whether the implanted larvae were fresh or cryopreserved. Survival and growth rates of the larvae did not differ among the primate and rodent hosts tested, with the exception of squirrel monkeys and rats, which were resistant to infection. Molting from L3 to fourth-stage larvae began on day 3 and continued through day 14 in the primates and rodents. The primate and rodent models developed in the present study will be useful for the study of the immunology and chemotherapy of onchocerciasis.


Assuntos
Modelos Animais de Doenças , Muridae/parasitologia , Onchocerca volvulus/crescimento & desenvolvimento , Primatas/parasitologia , Animais , Criopreservação , Cultura em Câmaras de Difusão , Feminino , Gerbillinae/parasitologia , Haplorrinos/parasitologia , Larva/crescimento & desenvolvimento , Larva/ultraestrutura , Masculino , Camundongos , Camundongos Endogâmicos/parasitologia , Onchocerca volvulus/ultraestrutura , Pan troglodytes/parasitologia , Ratos , Ratos Endogâmicos/parasitologia
7.
J Parasitol ; 78(3): 447-53, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1597787

RESUMO

The objectives of this project were to screen a variety of inbred rodent species and strains to determine their usefulness as surrogate hosts for the study of the early larval development of Onchocerca lienalis and then to use a selected model to study the induction of protective immunity. In the primary screen, 6 strains of mice, 5 strains of rats, jirds, and multimammate rats were tested. Animals were infected with fresh O. lienalis by subcutaneous implantation of third-stage larvae (L3) contained in diffusion chambers covered with 5.0-microns pore-size membranes. After 7 days the chambers were recovered, and larval viability and growth were assessed. Approximately one-half of inoculated larvae were recovered alive regardless of the host tested. Larvae were implanted in CBA/J and DBA/2J mice in chambers covered with membranes that prevented host cells from entering; survival and growth rates of the larvae were not altered by the absence of cells from the chambers. Cryopreserved larvae were implanted in chambers with 5.0-microns pore-size membranes in CBA/J and DBA/2J mice and Wistar Furth rats for 3-28 days. No statistically significant difference was seen in the larval recoveries on days 3-28 in all 3 hosts. Statistically significant increases in length were seen in the 3 strains from day 3 to day 14, after which growth appeared to cease. Molting from L3 to fourth-stage larvae was observed in all 3 hosts beginning on day 3, with most larvae completing the molt by day 7.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Modelos Animais de Doenças , Muridae , Onchocerca/crescimento & desenvolvimento , Oncocercose/imunologia , Animais , Criopreservação , Cultura em Câmaras de Difusão , Gerbillinae , Imunização , Larva/crescimento & desenvolvimento , Larva/imunologia , Masculino , Camundongos , Camundongos Endogâmicos , Onchocerca/imunologia , Oncocercose/parasitologia , Ratos , Ratos Endogâmicos
8.
Mol Gen Genet ; 225(1): 158-67, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1705653

RESUMO

In this paper we report the inability of four group I introns in the gene encoding subunit I of cytochrome c oxidase (cox1) and the group II intron in the apocytochrome b gene (cob) to splice autocatalytically. Furthermore we present the characterization of the first cox1 intron in the mutator strain anar-14 and the construction and characterization of strains with intronless mitochondrial genomes. We provide evidence that removal of introns at the DNA level (termed DNA splicing) is dependent on an active RNA maturase. Finally we demonstrate that the absence of introns does not abolish homologous mitochondrial recombination.


Assuntos
Íntrons , Mitocôndrias/metabolismo , Splicing de RNA , RNA/genética , Schizosaccharomyces/genética , Sequência de Aminoácidos , Apoproteínas/genética , Sequência de Bases , Clonagem Molecular , Sequência Consenso , Grupo dos Citocromos b/genética , Citocromos b , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Dados de Sequência Molecular , Conformação de Ácido Nucleico , RNA Mitocondrial
9.
J Mol Biol ; 202(4): 725-34, 1988 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-3172236

RESUMO

Mutator strains of the fission yeast Schizosaccharomyces pombe produce mitochondrial respiratory deficient mutants at a high rate, and roughly 20% of these mutants carry deletions in the range of 50 to 1500 base-pairs. To elucidate the mechanism of deletion we have sequenced ten deletion mutants in the mosaic gene encoding apocytochrome b (cob) and three in the split gene coding for the first subunit of cytochrome c oxidase (cox1). Of 13 deletions, ten are correlated with the presence of direct repeats, which could promote deletions by slipped mispairing during DNA replication. In some of these mutants, the termini are located in possible DNA secondary structures. In three independently isolated mutants with identical deletions in the cob gene, the 5' deletion endpoint coincides with the 3' splice point of the intron, whereas the 3' endpoint of the deletion exhibits pronounced homology with the 5' splice point of the intron. This result suggests that these deletions might be initiated by erroneous RNA splicing.


Assuntos
DNA Fúngico , DNA Mitocondrial , Mutação , Saccharomycetales/genética , Schizosaccharomyces/genética , Sequência de Bases , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Plasmídeos , Sequências Repetitivas de Ácido Nucleico
11.
Curr Genet ; 8(7): 517-24, 1984 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24177952

RESUMO

The three mutator strains ana (r)-8, ana (r)-14, and diu (r)-301 were shown to produce respiratory deficient mutants at different rates. The frequency of respiratory deficient mutants in a culture could be increased by adding ethidium bromide. According to their cytochrome spectra and enzymatic activities they form three classes, namely mutants defective in cytochrome oxidase, in cytochrome b, and in both cytochromes. By restriction enzyme analysis of mitochondrial DNA from about 100 mutants, 22 deletion mutants were identified. The deletions, ranging from 50 to 1,500 base pairs were physically mapped. Deletions were localized in the genes coding for subunit 1 of cytochrome oxidase with its two introns, within the cytochrome b gene and its intron, and within the genes for subunits 2 and 3 of cytochrome oxidase. In several cases, where the physical mapping yielded ambiguous results, pairwise genetic crosses ruled out an overlap between two neighbouring deletions.Using these mitochondrial deletion mutants as tester strains, it was shown that only tetrad analysis and chemical haploidization, but not mitotic segregation analysis, allows a decision between chromosomal and mitochondrial inheritance of respiratory deficiency in Schizosaccharomyces pombe.

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