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1.
Science ; 371(6533): 1038-1041, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33674491

RESUMO

Spectroscopy of transiting exoplanets can be used to investigate their atmospheric properties and habitability. Combining radial velocity (RV) and transit data provides additional information on exoplanet physical properties. We detect a transiting rocky planet with an orbital period of 1.467 days around the nearby red dwarf star Gliese 486. The planet Gliese 486 b is 2.81 Earth masses and 1.31 Earth radii, with uncertainties of 5%, as determined from RV data and photometric light curves. The host star is at a distance of ~8.1 parsecs, has a J-band magnitude of ~7.2, and is observable from both hemispheres of Earth. On the basis of these properties and the planet's short orbital period and high equilibrium temperature, we show that this terrestrial planet is suitable for emission and transit spectroscopy.

2.
Vet Parasitol ; 161(3-4): 302-6, 2009 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-19251369

RESUMO

The influence of re-wetting of pastures on the occurrence of important endoparasites in cattle was monitored over the course of three years. The study was conducted on a peninsula at the German North-Sea Coast. The cattle were stabled from November to April. During summer season, they were kept on pastures included in a nature protection program differentiating between three states of re-wetting. Faecal samples from randomly selected animals were analysed with routine diagnostic methods for the occurrence of Eimeria spp., nematode and trematode eggs and lungworm larvae. Samples were taken three times per year: before turning out, in the middle of the grazing season and at the end. After a diagnostic and plausibility check, a total of 692 samples could be used for statistical analysis. The overall prevalence was 29.5% for Eimeria spp. and 42.2% for nematodes. Eggs of the liver fluke and lungworm larvae were only detected at very low levels. Statistical analyses were performed with a generalized linear model including the fixed effects wetting status, farm, year, and if it was the first summer on pasture for the animal. Significant influences on nematodes were detected for the stage of re-wetting, while Eimeria spp. were significantly affected by the grazing period. These findings indicate that the important parasites liver fluke and lungworm have not hitherto been affected at all by re-wetting measures. Furthermore, the prevalence of nematodes and Eimeria spp. did not increase. In conclusion, no clinical signs for parasitic diseases and no significantly elevated infection levels were shown after the third year of re-wetting, but even longer observations are essential to evaluate long-term consequences.


Assuntos
Doenças dos Bovinos/parasitologia , Gastroenteropatias/veterinária , Doenças Parasitárias em Animais/parasitologia , Criação de Animais Domésticos , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Fezes/parasitologia , Gastroenteropatias/epidemiologia , Gastroenteropatias/parasitologia , Alemanha/epidemiologia , Contagem de Ovos de Parasitas/veterinária , Doenças Parasitárias em Animais/epidemiologia , Chuva
3.
Animal ; 2(9): 1273-80, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22443815

RESUMO

In spite of the improvement in management and the breeding goal of increasing the number of piglets born alive, piglet mortality is still a substantial problem in pig breeding. The objective of the first part of the study was to estimate genetic parameters for different causes of piglet losses and to investigate the relationship to litter-size traits. Data were collected on a nucleus herd from January till December 2004. Records from 943 German Landrace sows with 1538 pure-bred litters and 13 971 individually weighted piglets were included. Four different causes of piglet losses (LOSS) were evaluated. Additional analysed traits were underweight and runting. Furthermore, the fertility traits number of piglets born alive, born in total and stillborn piglets as well as the individual birth and weaning weights were analysed. The different LOSS were treated as a binary trait and subsequently the heritabilities were estimated using a threshold model. The most important LOSS was crushing under the sow (12.4%). The survival rate and crushing had a heritability of h2 = 0.03. The fertility traits piglets born alive, born in total and stillborn piglets were analysed with a linear model and heritabilities rank from h2 = 0.05 (stillborn) to h2 = 0.10 (born alive). The estimated heritabilities for birth- and weaning weight were both h2 = 0.10. The genetic correlations between number of piglets born alive and each LOSS trait were analysed bivariately. Of all piglets born alive 84.3% survive the lactation period. Survival decreased with increasing litter size (rg = -0.54 up to -0.78) and the probability of being crushed under the sow increased.

4.
Animal ; 2(9): 1281-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22443816

RESUMO

The aim of the study was to analyse the genetic background of different traits to characterise the maternal behaviour of sows and to evaluate the relationship to different causes of piglet losses - increasing piglet survival due to higher maternal abilities of the sow. A total of 1538 purebred litters from 943 German Landrace sows in the year 2004 were available for data analysis. Around 13 971 individually earmarked piglets were included in the analyses. Maternal abilities were characterised through the sow's reaction to the separation from her litter during the first 24 h after farrowing, and on day 21 of lactation, the reaction towards the playback of a piglet's distress call and the reaction towards an unknown noise (music). In 1220 of these litters, the sows were also scored for aggressiveness in the group when regrouped before entering the farrowing crates. To describe fertility, the number of piglets born alive, stillborn piglets, number of piglets born in total and the individual birth weight were utilised. Different causes of piglet losses were evaluated as binary traits of the dam with survival rate, different definitions for crushing by the sow, being underweight and runts. The heritability for being aggressive in the group was h2 = 0.32 and for the behaviour traits during lactation, the heritabilities ranged from h2 = 0.06 to 0.14. The genetic correlations showed that more-reactive sows had fewer piglet losses.

5.
Oncogene ; 25(55): 7297-304, 2006 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-16732314

RESUMO

BCL3 is a proto-oncogene affected by chromosomal translocations in some patients with chronic lymphocytic leukemia. It is an IkappaB family protein that is involved in transcriptional regulation of a number of NF-kappaB target genes. In this study, interleukin (IL)-6-induced BCL3 expression and its effect on survival of multiple myeloma (MM) cells were examined. We demonstrate the upregulation of BCL3 by IL-6 in INA-6 and other MM cell lines. Sequence analysis of the BCL3 gene locus revealed four potential signal transducer and activator of transcription (Stat) binding sites within two conserved intronic enhancers regions: one located within enhancer HS3 and three within HS4. Chromatin immunoprecipitation experiments showed increased Stat3 binding to both enhancers upon IL-6 stimulation. Silencing Stat3 expression by small interfering RNA (siRNA) abrogated BCL3 expression by IL-6. Using reporter gene assays, we demonstrate that BCL3 transcription depends on HS4. Mutation of the Stat motifs within HS4 abolished IL-6-dependent BCL3 induction. Furthermore, BCL3 transcription was inhibited by its own gene product. This repressive feedback is mediated by NF-kappaB sites within the promoter and HS3. Finally, we show that overexpression of BCL3 increases apoptosis, whereas BCL3-specific siRNA does not affect the viability of INA-6 cells suggesting that BCL3 is not essential for the survival of these cells.


Assuntos
Elementos Facilitadores Genéticos , Interleucina-6/metabolismo , Íntrons , Proteínas Proto-Oncogênicas/biossíntese , Fator de Transcrição STAT3/metabolismo , Fatores de Transcrição/biossíntese , Transcrição Gênica , Proteína 3 do Linfoma de Células B , Sequência de Bases , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Primers do DNA , Inativação Gênica , Humanos , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Ligação Proteica , Proto-Oncogene Mas
6.
Exp Neurol ; 187(1): 199-202, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15081601

RESUMO

We previously reported an association between the N-acetyltransferase 2 (NAT2) slow acetylator status and Parkinson's disease (PD). We have now investigated the possible functional relevance of this association by treating Fischer 344 (F344) rapid and Wistar-Kyoto (WKY) slow NAT2 acetylator rat strains with the neurotoxin 6-hydroxydopamine (6-OHDA). Intrastriatal treatment with either 10 or 20 microg of 6-OHDA lead to a significantly greater reduction of striatal dopamine concentrations in the WKY slow acetylator rat strain than in the F344 rapid acetylator rat strain (P < 0.004), reflecting a more marked degree of dopaminergic denervation. Nigral dopaminergic cell counts were also lower in the WKY rats, but this difference failed to reach statistical significance, suggesting that slow acetylation is especially deleterious at the level of striatal nerve endings.


Assuntos
Arilamina N-Acetiltransferase/metabolismo , Dopamina/metabolismo , Neostriado/efeitos dos fármacos , Neostriado/metabolismo , Oxidopamina/toxicidade , Animais , Arilamina N-Acetiltransferase/genética , Contagem de Células , Resistência a Medicamentos/genética , Masculino , Neostriado/citologia , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos WKY , Especificidade da Espécie , Substância Negra/citologia , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo , Tirosina 3-Mono-Oxigenase/biossíntese
7.
Immunobiology ; 202(2): 151-67, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10993289

RESUMO

Interleukin-6 (IL-6) is a pleiotropic cytokine that acts on a wide variety of cell types. It has important regulatory functions in the immune system, is a mediator of the acute-phase response, and is involved in the regulation of differentiation, proliferation, and survival of target cells. A major signal transduction pathway for IL-6 involves activation of JAK kinases and the transcription factor Stat3. In addition, a great many of other signalling pathways are induced. Stat3 has been shown to be a central player of IL-6 signalling in many systems whereas the functions of most other IL-6-activated pathways are not yet understood. In this review, we discuss the current knowledge on IL-6 functions in the immune system, IL-6 signal transduction, and its significance for lymphocyte function.


Assuntos
Linfócitos B/imunologia , Proteínas de Ligação a DNA/imunologia , Interleucina-6/imunologia , Proteínas Tirosina Quinases/imunologia , Proteínas Proto-Oncogênicas , Transdução de Sinais , Linfócitos T/imunologia , Transativadores/imunologia , Animais , Humanos , Sistema Imunitário/imunologia , Janus Quinase 1 , Janus Quinase 2 , Receptores de Interleucina-6/imunologia , Fator de Transcrição STAT3
9.
Trends Ecol Evol ; 13(3): 105-9, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21238221

RESUMO

Systematists and comparative biologists commonly want to make statements about relationships among taxa that have never been collectively included in any single phylogenetic analysis. Construction of phylogenetic 'supertrees' provides one solution. Supertrees are estimates of phylogeny assembled from sets of smaller estimates (source trees) sharing some but not necessarily all their taxa in common. If certain conditions are met, supertrees can retain all or most of the information from the source trees and also make novel statements about relationships of taxa that do not co-occur on any one source tree. Supertrees have commonly been constructed using subjective and informal approaches, but several explicit approaches have recently been proposed.

10.
J Clin Endocrinol Metab ; 81(2): 565-70, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8636268

RESUMO

The pulsatile release pattern of LH during the entire menstrual cycle is well defined; however, the response of corpora lutea to these LH pulses in patients suffering from corpus luteum insufficiencies (CLI) is largely unknown. Patients suffering from CLI were selected from infertile patients on the basis of low progesterone (P < 25 nmol/L) in a blood sample withdrawn during a monitoring cycle. During the next cycle, nine blood samples were collected during the follicular and luteal phase and follicular development was assessed by vaginal sonography. Of 109 patients who had a CLI in the monitoring cycle, 55 had a CLI again, and 38 women agreed to undergo assessment of pulsatile hormone secretion. These women again had P < 25 nmol/L at days 6 and 7 of the luteal phase and blood samples were withdrawn through antecubital vein catheters from 0900-1700 h at 10-min intervals on days 7, 8, or 9 following ovulation. From 38 patients with such defined CLI, 16 (42%) had no LH episode and significantly lower basal LH levels in comparison with 14 control subjects. Thirteen (34%) of the patients had normal appearing LH episodes despite too low P and E2 concentrations, but their CL did not react to the LH episodes. The remaining 9 patients (24%) had normal LH episodes; their CL reacted to these episodes, but their basal P levels were too low. In all blood samples LH was not only determined using an immunoassay but also by the mouse Leydig cell testosterone production bioassay. It could be established that no CLI exists, which is due to the release of bioinactive LH. It is anticipated that the differentiation of three different types of CLI, one of hypothalamic and two of ovarian origin, may allow the development of differential diagnostic and therapeutic tools in the future.


Assuntos
Corpo Lúteo/metabolismo , Hormônio Luteinizante/metabolismo , Doenças Ovarianas/fisiopatologia , Adulto , Animais , Bioensaio , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Infertilidade Feminina/etiologia , Infertilidade Feminina/fisiopatologia , Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/metabolismo , Hormônio Luteinizante/sangue , Hormônio Luteinizante/farmacologia , Masculino , Camundongos , Doenças Ovarianas/complicações , Periodicidade , Progesterona/sangue , Prolactina/sangue , Testosterona/biossíntese
11.
Eur J Endocrinol ; 133(6): 701-17, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8548056

RESUMO

In 54 healthy women luteal function was assessed by sequential withdrawals of blood samples at 10-min intervals for 8-10 h. Subgroups of the women were studied during the early and late ovulatory period and during the early, mid- and late luteal phase. Bio- and immunoreactive luteinizing hormone (LH), prolactin, testosterone, estradiol and progesterone levels were determined in each sample. While the bio- and immunoreactivity of LH pulses correlated fairly well, a number of bio- or immunoreactive LH pulses were observed that were not detected by the respective other method. Responsivity of the corpus luteum to LH episodes developed during the second half of the luteal phase and was most marked in cases where LH episodes were accompanied by prolactin episodes. In the absence of prolactin episodes. LH episodes did not stimulate progesterone or estradiol secretion. The highest incidence of coincident LH and prolactin pulses was observed during the mid- and late luteal phase. Serum testosterone levels showed also some fluctuations but these were independent of immuno- or bioactive LH episodes and therefore most likely not of luteal origin. Prior to menstruation LH episodes were not any more stimulatory to progesterone secretion, indicating that it is not the withdrawal of LH but, rather, another possibly intraovarian mechanism that results in luteolysis. In a number of women, increased estradiol and progesterone secretion was strictly related to the prior occurrence of LH and prolactin pulses. In other subjects, both gonadal steroids fluctuated largely with no discernible correlation to LH fluctuations. This may indicate that in these subjects the corpora lutea have some degree of autonomous regulation.


Assuntos
Corpo Lúteo/fisiologia , Fase Luteal/fisiologia , Hormônio Luteinizante/fisiologia , Prolactina/fisiologia , Adolescente , Adulto , Estradiol/sangue , Feminino , Humanos , Hormônio Luteinizante/sangue , Ovulação/fisiologia , Progesterona/sangue , Prolactina/sangue , Testosterona/sangue , Fatores de Tempo
12.
Geburtshilfe Frauenheilkd ; 50(12): 941-6, 1990 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-2128287

RESUMO

The CA-125-antigen could not only be identified in the epithelium of serous ovarian carcinoma, but also in the regular surface epithelium of the endometrium, the decidua and the peritoneum. The aim of this study was, to examine the pattern of CA-125 in the serum of women at early stages of pregnancy, after hMG/hCG-stimulation and subsequent insemination, IVF or GIFT. In particular, it was differentiated between simple or twin pregnancies, ovarian hyperstimulation syndrome and mole pregnancies. 16 patients, who spontaneously became pregnant after cyclus-monitoring, served as a control group. Among the total of 77 patients, 16 women with single pregnancies without stimulation showed an increase of CA-125 values to maximum amounts of 42.9 +/- 18.8 U/ml in the 8th week. 21 patients with single pregnancies after hMG/hCG-treatment and IVF, exhibited maximums of 97.5 +/- 66.8 U/ml in the 6th week, in cases of twins (n = 10) of 216.8 +/- 85.1 U/ml in the 7th week. Considering the group with the hMG/hCG-stimulation and following insemination (n = 20), maximum values of 91.4 +/- 57.3 U/ml were found in the 6th week, just as in the IVF-group. In cases of ovarian hyperstimulation syndrome (n = 5) as well as in such of a mole pregnancy (n = 5), drastically elevated values of 9519 and 1496 U/ml respectively, have been demonstrated. The decidua is regarded as a presumable source of high antigen levels in normal pregnancy, while the peritoneum is assumed to be such as for the ovarian hyperstimulation syndrome. Concerning mole pregnancy, the antigen levels could possibly emerge from the amniotic fluid.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Biomarcadores Tumorais/sangue , Gonadotropina Coriônica/administração & dosagem , Fertilização in vitro , Transferência Intrafalopiana de Gameta , Infertilidade Feminina/sangue , Menotropinas/administração & dosagem , Feminino , Humanos , Mola Hidatiforme/sangue , Mola Hidatiforme/diagnóstico , Infertilidade Feminina/terapia , Gravidez , Primeiro Trimestre da Gravidez , Gravidez Múltipla/sangue , Estudos Prospectivos , Radioimunoensaio , Valores de Referência , Neoplasias Uterinas/sangue , Neoplasias Uterinas/diagnóstico
14.
Science ; 153(3737): 688, 1966 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-17791113
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