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1.
Clin Psychol Psychother ; 23(6): 543-549, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26857479

RESUMO

Suicide is a major cause of death in adulthood and specifically in patients suffering from mental illnesses. The Depressive Symptom Inventory Suicidality Subscale (DSI-SS) is widely used to detect and prevent suicidal ideation. The aim of the present study was to determine optimal cut points for the DSI-SS in different populations. We analysed the data of one population-based sample (n = 532), one outpatient sample (n = 180) and one inpatient sample (n = 244). Internal consistency, convergent validity and optimal cut points according to receiver operating characteristics were calculated. In all samples, we found excellent item-total correlations and internal consistencies for the DSI-SS. Zero-order correlations between the DSI-SS and theoretically related constructs showed positive correlation coefficients, ranging from 0.50 to 0.67. The DSI-SS differentiated well between patients with and without suicide attempts in the population-based sample, but less so in the inpatient sample and only marginally in the outpatient sample. A bootstrapping analysis showed some variability in the cut points that emerged as optimal, but there was no overlap between the different samples. The specific cut points that we identified may be used to improve the diagnostic utility of the DSI-SS and the chance to detect suicidal ideation. Copyright © 2016 John Wiley & Sons, Ltd. KEY PRACTITIONER MESSAGE: We developed cut points for the Depressive Symptom Inventory Suicidality Subscale, to improve the early and valid detection of suicidal ideation by this measure. The cut points that were identified as optimal varied between the samples. The cut points differentiated well in a non-clinical sample, but less well in outpatient and inpatient samples.


Assuntos
Transtorno Depressivo/diagnóstico , Transtorno Depressivo/psicologia , Prevenção do Suicídio , Suicídio/psicologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria , Ideação Suicida , Adulto Jovem
2.
Nervenarzt ; 86(5): 566-70, 2015 May.
Artigo em Alemão | MEDLINE | ID: mdl-24943362

RESUMO

BACKGROUND: As a particular aspect of psychiatric clinical training many students instinctively harbor reservations towards the field of electroconvulsive treatment (ECT). In this context the question arises how controversial issues, such as ECT can be addressed during the placement. The clinical training is predestined to provide basic knowledge concerning ECT for future doctors. As multipliers and potential referrers they then can work to prevent severe mental illness from becoming chronic. MATERIALS AND METHODS: Prior to the clinical psychiatric teaching course 158 medical students of the RWTH Aachen University were randomly assigned to three groups. The first actively took part in an ECT therapy session (ECT group), the second was shown an educational video (video group) and the third served as a control group. A questionnaire was filled in before and after the training concerning the knowledge and the attitudes towards ECT. RESULTS: In the course of the clinical training the attitudes of the students towards ECT became more positive for all items. The willingness to agree to ECT in the case of patients, family members and friends and themselves increased in the ECT group and the video group but not in the control group. Only the ECT group proved to be superior to the control group in the direct comparisons. In both interventions the knowledge about ECT increased more in comparison to the control group despite the very limited interventions. CONCLUSION: Reservations to touch on the controversial issue of ECT during the clinical training do not seem to be justified. Even a single hands-on or video experience can have a relevant impact on knowledge and attitude towards ECT in medical students. This opportunity should be used more intensively.


Assuntos
Atitude Frente a Saúde/etnologia , Currículo , Eletroconvulsoterapia/estatística & dados numéricos , Assistência Centrada no Paciente/estatística & dados numéricos , Estudantes de Medicina/estatística & dados numéricos , Ensino/métodos , Adulto , Eletroconvulsoterapia/psicologia , Feminino , Alemanha , Humanos , Masculino , Estudantes de Medicina/psicologia
3.
Proc Natl Acad Sci U S A ; 106(10): 3758-63, 2009 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-19223588

RESUMO

Cells have evolved biomolecular networks that process and respond to changing chemical environments. Understanding how complex protein interactions give rise to emergent network properties requires time-resolved analysis of cellular response under a large number of genetic perturbations and chemical environments. To date, the lack of technologies for scalable cell analysis under well-controlled and time-varying conditions has made such global studies either impossible or impractical. To address this need, we have developed a high-throughput microfluidic imaging platform for single-cell studies of network response under hundreds of combined genetic perturbations and time-varying stimulant sequences. Our platform combines programmable on-chip mixing and perfusion with high-throughput image acquisition and processing to perform 256 simultaneous time-lapse live-cell imaging experiments. Nonadherent cells are captured in an array of 2,048 microfluidic cell traps to allow for the imaging of eight different genotypes over 12 h and in response to 32 unique sequences of stimulation, generating a total of 49,000 images per run. Using 12 devices, we carried out >3,000 live-cell imaging experiments to investigate the mating pheromone response in Saccharomyces cerevisiae under combined genetic perturbations and changing environmental conditions. Comprehensive analysis of 11 deletion mutants reveals both distinct thresholds for morphological switching and new dynamic phenotypes that are not observed in static conditions. For example, kss1Delta, fus3Delta, msg5Delta, and ptp2Delta mutants exhibit distinctive stimulus-frequency-dependent signaling phenotypes, implicating their role in filtering and network memory. The combination of parallel microfluidic control with high-throughput imaging provides a powerful tool for systems-level studies of single-cell decision making.


Assuntos
Imageamento Tridimensional/instrumentação , Sistema de Sinalização das MAP Quinases , Microfluídica/instrumentação , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/enzimologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fator de Acasalamento , Mutação/genética , Peptídeos/farmacologia , Fenótipo , Feromônios/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/fisiologia
4.
Poult Sci ; 91(4): 998-1008, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22399740

RESUMO

Stunning effectiveness of male and female broiler chickens was analyzed in response to different waveforms at 3 constant voltage levels. In total, 180 male and female broiler chickens were stunned using a sine wave alternating current (AC) of 50 Hz, rectangular AC of 70 Hz, and pulsed direct current (DC) of 70 Hz (duty-cycle 1:1) with a constant voltage of 60, 80, or 120 V, respectively. In each stunning group, 10 male and 10 female birds were stunned for 4 s. The current obtained by every bird was recorded. For stunning efficiency, the electroencephalogram (EEG) and physical reflexes were recorded and analyzed. The EEG was recorded for 120 s poststun. Simultaneously, the occurrence of spontaneous eye blinking, wing flapping, and breathing was assessed, and the corneal reflex was tested every 20 s poststun. The EEG was analyzed regarding the occurrence of a profound suppression to less than 10% of the prestun level in the 2 to 30 Hz and 13 to 30 Hz bands. Female broilers obtained a significantly lower stunning current compared with that of the males. This resulted in a lower stunning efficiency for females, when the same constant voltage was applied to males and females. The waveforms required different amounts of currents to achieve a 90% stunning efficiency. A minimum necessary stunning current of 70, 90, and 130 mA could be established for sine wave AC, rectangular AC, and pulsed DC, respectively. The low stunning efficiency of pulsed DC might be caused by the short stunning time of 4 s. This effect should be further investigated for DC stunning. Very few birds stunned with AC resumed breathing following stunning, indicating stun to kill. Pulsed DC stunning showed a lower effect on the induction of death. The level of wing flapping, indicating convulsions and possible meat quality defects, was higher for the AC treatments.


Assuntos
Galinhas/fisiologia , Eletricidade/efeitos adversos , Eletrochoque/veterinária , Inconsciência/veterinária , Matadouros , Bem-Estar do Animal , Animais , Eletroencefalografia/veterinária , Radiação Eletromagnética , Eletrochoque/métodos , Eletrochoque/mortalidade , Feminino , Análise de Fourier , Modelos Logísticos , Masculino , Distribuição Aleatória , Reflexo , Fatores Sexuais , Inconsciência/mortalidade , Água
5.
Fortschr Neurol Psychiatr ; 80(8): 463-7, 2012 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-22777885

RESUMO

We report on the case of a 63-year-old patient with a meningoencephalitis, presenting itself with headache and a general neuropsychological retardation. Additionally, a reddening and swelling of both auricles could be seen. Magnetic resonance imaging showed confluent, contrast-uptaking lesions. In the cerebrospinal fluid an aseptic lymphocytic pleocytosis was found. A biopsy of the ear revealed a chronic lymphoplasmacellular inflammatory reaction. We diagnosed a relapsing polychrondritis, an inflammatory disease of the cartilage, which can in rare cases affect the central nervous system. Typically, the patients complain about red swollen ears, the "red puffy ear sign". After initiation of steroid and azathioprin therapy the patient recovered fully.


Assuntos
Orelha Externa/patologia , Meningoencefalite/diagnóstico , Meningoencefalite/patologia , Policondrite Recidivante/diagnóstico , Policondrite Recidivante/patologia , Anti-Inflamatórios/uso terapêutico , Azatioprina/uso terapêutico , Biópsia , Cefaleia/etiologia , Humanos , Imunossupressores/uso terapêutico , Leucocitose/líquido cefalorraquidiano , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Prednisolona/uso terapêutico
6.
Poult Sci ; 89(6): 1265-74, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20460673

RESUMO

Stunning efficiency of broilers after electrical waterbath stunning with an alternating current was assessed using electroencephalograms (EEG) and physical reflexes. Four hundred eighty-nine broilers (246 males and 243 females) were stunned in an electrical waterbath with a rectangular alternating stunning current of 60, 80, 100, 120, and 150 mA and frequencies of 70, 100, 200, 400, 800, and 1,500 Hz. Stunning time was 10 s. The EEG was recorded for 120 s poststun. Occurrence of spontaneous breathing, eye blinking, and wing flapping and the corneal reflex were recorded. The EEG was analyzed regarding the occurrence of a profound suppression to less than 10% of the prestun level in the 2 to 30-Hz band and 13 to 30-Hz band. The occurrence of epileptiform patterns was assessed and the occurrence of clonic-tonic convulsions was recorded. Statistical analysis showed a highly significant effect of stunning frequency and stunning current for all groups in the EEG analysis. Stunning frequencies above 400 Hz or below 100 mA did not result in profound suppression of brain power to less than 10% of the prestun level in more than 90% of the broilers and can therefore not be recommended. More than 80% of the birds stunned with 70 or 100 Hz at 100 mA or 70, 100, and 200 Hz with 120 and 150 mA did not recover from stunning. The occurrence of epileptiform activity could only be observed in a few birds. It is assumed that this is due to the long stunning time of 10 s and epileptiform activity could have occurred just before EEG recording started. A maximum of 30% of birds with corneal reflexes and spontaneous eye blinking should not be exceeded, whereas at 15 s poststun, not more than 15% of birds should show spontaneous eye blinking. Wing flapping occurred in at least 50% of birds with adequate stunning results. This seems to be related to convulsions and could cause meat quality defects.


Assuntos
Galinhas/fisiologia , Eletroencefalografia/veterinária , Eletrochoque/veterinária , Matadouros , Animais , Eletricidade , Masculino , Reflexo , Água
7.
Poult Sci ; 89(6): 1275-84, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20460674

RESUMO

Stunning efficiency of a pulsed direct current was assessed regarding the effect on the electroencephalogram (EEG) and physical reflexes. Four hundred sixty-seven broilers (males and females) were stunned in an electrified waterbath with 60, 80, 100, 120, and 150 mA at frequencies of 70, 100, 200, 400, 800, and 1,500 Hz. Stunning time was 10 s. The EEG recordings lasted for 120 s poststun and simultaneously the occurrence of breathing, spontaneous eye blinking, corneal reflex, and wing flapping was recorded. The EEG records were assessed regarding a profound suppression to less than 10% of the prestun brain power in 2 brain frequency bands, 2 to 30 Hz and 13 to 30 Hz. The EEG results showed a significant effect of stunning frequency for all analyzed parameters. Stunning frequencies of 800 and 1,500 Hz did not achieve adequate stunning results. With a minimum stunning current of 120 mA at frequencies of 70 or 100 Hz or 150 mA at 200 Hz, more than 80% of the animals did not resume breathing. Currents of 80 and 100 mA at 70 or 100 Hz achieved unconsciousness in more than 90% of the birds and birds recovered within 30 to 40 s poststun. Epileptiform activity was found in a relatively low proportion of EEG traces. This could be explained by the long stunning time of 10 s, in which epileptiform activity might have occurred already before the start of EEG recording. Direct current stunning causes less cardiac arrest during stunning, but occurrence of breathing seems more related to cardiac function than to consciousness. A maximum of 30% corneal reflexes and spontaneous eye blinking seems acceptable with a maximum of 15% spontaneous blinking at 15 s poststun. Fourty percent of wing flapping occurred in all effectively stunned groups. Direct current seems to have a different effect on male and female broilers because significantly more male broilers showed reflexes, whereas simultaneously the likelihood of profound EEG suppression was higher. Further investigation of this effect is necessary.


Assuntos
Galinhas/fisiologia , Eletroencefalografia/veterinária , Eletrochoque/veterinária , Matadouros , Animais , Eletricidade , Feminino , Masculino , Reflexo , Água
8.
Science ; 278(5337): 460-3, 1997 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-9334304

RESUMO

Proteolysis mediated by the anaphase-promoting complex (APC) triggers chromosome segregation and exit from mitosis, yet its regulation is poorly understood. The conserved Cdc20 and Cdh1 proteins were identified as limiting, substrate-specific activators of APC-dependent proteolysis. CDC20 was required for the degradation of the APC substrate Pds1 but not for that of other APC substrates, such as Clb2 and Ase1. Conversely, cdh1Delta mutants were impaired in the degradation of Ase1 and Clb2 but not in that of Pds1. Overexpression of either CDC20 or CDH1 was sufficient to induce APC-dependent proteolysis of the appropriate target in stages of the cell cycle in which substrates are normally stable.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Ciclina B , Proteínas Fúngicas/metabolismo , Ligases/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Complexos Ubiquitina-Proteína Ligase , Ciclossomo-Complexo Promotor de Anáfase , Proteínas Cdc20 , Proteínas de Ciclo Celular/genética , Ciclinas/metabolismo , Proteínas Fúngicas/genética , Fase G1 , Mitose , Mutação , Proteínas Nucleares/metabolismo , Fases de Leitura Aberta , Fase S , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Securina , Especificidade por Substrato , Ubiquitina-Proteína Ligases
9.
Sci Adv ; 5(4): eaav4310, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31001586

RESUMO

Anaerobic ammonium oxidation (anammox) is a major process in the biogeochemical nitrogen cycle in which nitrite and ammonium are converted to dinitrogen gas and water through the highly reactive intermediate hydrazine. So far, it is unknown how anammox organisms convert the toxic hydrazine into nitrogen and harvest the extremely low potential electrons (-750 mV) released in this process. We report the crystal structure and cryo electron microscopy structures of the responsible enzyme, hydrazine dehydrogenase, which is a 1.7 MDa multiprotein complex containing an extended electron transfer network of 192 heme groups spanning the entire complex. This unique molecular arrangement suggests a way in which the protein stores and releases the electrons obtained from hydrazine conversion, the final step in the globally important anammox process.


Assuntos
Proteínas de Bactérias/química , Heme/química , Oxirredutases/química , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Domínio Catalítico , Microscopia Crioeletrônica , Cristalografia por Raios X , Transporte de Elétrons , Bactérias Gram-Negativas/enzimologia , Oxirredutases/metabolismo , Estrutura Quaternária de Proteína
10.
Curr Biol ; 8(13): 750-60, 1998 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-9651679

RESUMO

BACKGROUND: In eukaryotic cells, a specialized proteolysis machinery that targets proteins containing destruction-box sequences for degradation and that uses a ubiquitin ligase known as the anaphase-promoting complex/cyclosome (APC) plays a key role in the regulation of mitosis. APC-dependent proteolysis triggers the separation of sister chromatids at the metaphase-anaphase transition and the destruction of mitotic cyclins at the end of mitosis. Recently, two highly conserved WD40-repeat proteins, Cdc20 and Cdh1/Hct1, have been identified as substrate-specific regulators for APC-dependent proteolysis in the budding yeast Saccharomyces cerevisiae. Here, we have investigated the cell cycle regulation of Cdc20 and Cdh1/Hct1. RESULTS: Whereas the levels CDH1/HCT1 RNA and Cdh1/Hct1 protein are constant throughout the cell cycle, CDC20 RNA and Cdc20 protein are present only during late S phase and mitosis and Cdc20 protein is unstable throughout the entire cell cycle. The instability of Cdc20 depends on CDC23 and CDC27, which encode components of the APC. During the G1 phase, a destruction box within Cdc20 mediates its instability, but during S phase and mitosis, although Cdc20 destruction is still dependent on CDC23 and CDC27, it does not depend on the Cdc20 destruction box. CONCLUSIONS: There are remarkable differences in the regulation of Cdc20 and Cdh1/Hct1. Furthermore, the APC activator Cdc20 is itself a substrate of the Cdc27 have a role in the degradation of Cdc20 during S Phase and early mitosis that is not mediated by its destruction box.


Assuntos
Proteínas de Ciclo Celular/fisiologia , Ciclina B , Proteínas Fúngicas/fisiologia , Ligases/fisiologia , Mitose/fisiologia , Fase S/fisiologia , Proteínas de Saccharomyces cerevisiae , Complexos Ubiquitina-Proteína Ligase , Ciclossomo-Complexo Promotor de Anáfase , Antígenos CD , Subunidade Apc3 do Ciclossomo-Complexo Promotor de Anáfase , Subunidade Apc8 do Ciclossomo-Complexo Promotor de Anáfase , Caderinas , Desidrogenases de Carboidrato/metabolismo , Proteínas Cdc20 , Proteínas Cdh1 , Ciclinas/genética , Proteínas Fúngicas/metabolismo , Fase G1/fisiologia , RNA Fúngico/metabolismo , Saccharomyces cerevisiae , Transcrição Gênica/genética , Ubiquitina-Proteína Ligases
11.
J Neurosci ; 20(23): 8637-42, 2000 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11102468

RESUMO

Interleukin-6 (IL-6) has neuromodulatory and neuroprotective effects in vivo. It is expressed in glial cells and neurons both under physiological conditions and in various neurological diseases. Although the expression of IL-6 in glia has been intensely investigated, little is known about the regulation of IL-6 production by neurons. Therefore, we investigated the regulation of IL-6 expression in neurons. Membrane depolarization raised IL-6 mRNA accumulation in primary cortical cells and the PC-12 cell line. In vivo, IL-6 mRNA in the brain increased significantly after epileptic seizures. To investigate IL-6 gene transcription, PC-12 cells were transfected with reporter gene constructs containing the human IL-6 promoter. Membrane depolarization raised IL-6 transcription twofold to fourfold. This increase could be blocked by lowering extracellular Ca(2+) levels or by inhibiting L-type Ca(2+) channels or Ca(2+)/calmodulin-dependent protein kinases. Internal mutations in various elements of the IL-6 promoter revealed the glucocorticoid response element (GRE) 2 to be a depolarization-responsive element. Although the GRE2 bound the glucocorticoid receptor (GR) and was stimulated by dexamethasone, the GR was not responsible for the effect of membrane depolarization because a consensus GRE did not mediate stimulation by membrane depolarization. Instead, another yet undefined factor that binds to the IL-6 GRE2 may mediate the response to membrane depolarization. These data demonstrate that the expression of IL-6 in neurons is regulated by membrane depolarization and suggest a novel Ca(2+)-responsive promoter element. Through this mechanism, IL-6 may function as a neuromodulator induced by neuronal activity.


Assuntos
Regulação da Expressão Gênica/fisiologia , Interleucina-6/genética , Interleucina-6/metabolismo , Neurônios/metabolismo , Animais , Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio Tipo L/metabolismo , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Células Cultivadas , Dexametasona/farmacologia , Espaço Extracelular/metabolismo , Genes Reporter , Masculino , Camundongos , Mutagênese Sítio-Dirigida , Neurônios/citologia , Células PC12 , Potássio/metabolismo , Potássio/farmacologia , Regiões Promotoras Genéticas/genética , RNA Mensageiro/metabolismo , Ratos , Receptores de Glucocorticoides/metabolismo , Sequências Reguladoras de Ácido Nucleico/efeitos dos fármacos , Sequências Reguladoras de Ácido Nucleico/genética , Transcrição Gênica/efeitos dos fármacos , Transfecção
12.
Genetics ; 146(3): 781-95, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9215887

RESUMO

We have designed a screen to isolate mutants defective during a specific part of meiotic prophase I of the yeast Saccharomyces cerevisiae. Genes required for the repair of meiotic double-strand breaks or for the separation of recombined chromosomes are targets of this mutant hunt. The specificity is achieved by selecting for mutants that produce viable spores when recombination and reductional segregation are prevented by mutations in SPO11 and SPO13 genes, but fail to yield viable spores during a normal Rec+ meiosis. We have identified and characterized a mutation com1-1, which blocks processing of meiotic double-strand breaks and which interferes with synaptonemal complex formation, homologous pairing and, as a consequence, spore viability after induction of meiotic recombination. The COM1/SAE2 gene was cloned by complementation, and the deletion mutant has a phenotype similar to com1-1, com1/sae2 mutants closely resemble the phenotype of rad50S, as assayed by phase-contrast microscopy for spore formation, physical and genetic analysis of recombination, fluorescence in situ hybridization to quantify homologous pairing and immunofluorescence and electron microscopy to determine the capability to synapse axial elements.


Assuntos
Proteínas Fúngicas/genética , Meiose/genética , Recombinação Genética , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Clonagem Molecular , Elementos de DNA Transponíveis , DNA Fúngico/genética , Endonucleases , Raios gama , Genes Fúngicos , Mutagênese Insercional , Mutação , Prófase , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/fisiologia , Saccharomyces cerevisiae/efeitos da radiação , Esporos Fúngicos
13.
Z Naturforsch C J Biosci ; 56(7-8): 521-5, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11531084

RESUMO

The detailed investigation of a methanolic extract of aerial parts of Achillea pannonica SCHEELE. within a chemotaxonomic study led to the isolation of 6 flavonoid glycosides. Besides rutin, apigenin-7-O-glucopyranoside, luteolin-7-O-glucopyranoside, apigenin-7-O-rutinoside and acacetin-7-O-rutinoside, an unusual flavondiglucoside was isolated. Its structure was established by UV, 1H NMR and 13C NMR spectroscopic methods including 2D-NMR techniques and ESI-MS as luteolin-7,4'-O-beta-diglucoside. This substance is reported for the first time in the genus Achillea. Chemotaxonomic aspects are discussed briefly.


Assuntos
Asteraceae/química , Flavonoides/química , Glicosídeos/química , Cromatografia em Camada Fina , Flavonoides/isolamento & purificação , Flavonóis , Glicosídeos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Conformação Molecular , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray
14.
J Fam Pract ; 10(5): 885-90, 1980 May.
Artigo em Inglês | MEDLINE | ID: mdl-7391767

RESUMO

Umbilical vessel catheterization has become a commonly performed procedure in intensive care nurseries across the country. Catheterizing umbilical vessels can be a lifesaving step when newborn infant resuscitation is required. Moreover, considerable diagnostic and therapeutic advantages can be achieved for certain sick infants in observation or special care nurseries. The procedure requires careful patient selection and proper technical performance.


Assuntos
Cateterismo/métodos , Cordão Umbilical/irrigação sanguínea , Cateteres de Demora , Humanos , Recém-Nascido , Artérias Umbilicais , Veias Umbilicais
15.
Neuropeptides ; 46(5): 211-5, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22884888

RESUMO

The neuropeptide oxytocin has become a subject of great interest in studies investigating human social cognition. Single intranasal administration of the hormone has been reported to have positive behavioral effects, such as increasing trust or facilitating social approach, 45-80 min after administration. However, little is still known about the long-term pharmacokinetics of oxytocin nasal spray application in humans. This study addressed the question how long oxytocin plasma levels remain elevated following nasal spray administration. Another goal was to examine the influence of oxytocin administration on endogenous steroid hormones since such alterations might modulate social behavior via an indirect way. Eight healthy Caucasian men were challenged with a single intranasal application of 26 international units of oxytocin. Changes in oxytocin blood plasma levels, as well as steroid hormone levels of progesterone, testosterone and estradiol were assessed at 5 consecutive time points over a period of 3.5 h (-5, +30, +90, +150, +210 min relative to oxytocin administration). Results gave evidence for a substantial rise of oxytocin plasma levels 30 min after intranasal administration, observed in 7 of 8 participants. Group mean oxytocin plasma level was found to have returned to baseline already 90 min post administration, though in some individuals the plasma levels was still elevated relative to sampling at post 150 min. Steroid hormone analyses yielded a slight augmentation of endogenous testosterone levels 210 min after oxytocin administration. Our data confirms previous findings that oxytocin administered as a nasal spray enters the blood circulation, elevating oxytocin plasma levels for a limited time. Our findings suggest that this time window differs between individuals, but that, for the used dose, it does not extend beyond 150 min post administration. The data further provides preliminary evidence that intranasal oxytocin has an enhancing effect on testosterone in healthy men.


Assuntos
Ocitocina/administração & dosagem , Ocitocina/sangue , Administração Intranasal , Adulto , Estradiol/sangue , Humanos , Masculino , Ocitocina/farmacocinética , Progesterona/sangue , Testosterona/sangue
16.
J Bacteriol ; 183(7): 2372-5, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11244080

RESUMO

During sporulation in diploid Saccharomyces cerevisiae, spindle pole bodies acquire the so-called meiotic plaque, a prerequisite for spore formation. Mpc70p is a component of the meiotic plaque and is thus essential for spore formation. We show here that MPC70/mpc70 heterozygous strains most often produce two spores instead of four and that these spores are always nonsisters. In wild-type strains, Mpc70p localizes to all four spindle pole bodies, whereas in MPC70/mpc70 strains Mpc70p localizes to only two of the four spindle pole bodies, and these are always nonsisters. Our data can be explained by conservative spindle pole body distribution in which the two newly synthesized meiosis II spindle pole bodies of MPC70/mpc70 strains lack Mpc70p.


Assuntos
Proteínas Fúngicas/fisiologia , Meiose , Saccharomyces cerevisiae/fisiologia , Esporos Fúngicos/fisiologia
17.
Nucleic Acids Res ; 23(17): 3449-56, 1995 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-7567455

RESUMO

We have studied the bipartite regulatory element UASH/URS1 in the promoter of HOP1, whose product is required for synapsis and correct pairing of homologous chromosomes during the first meiotic division. HOP1 is transcriptionally repressed by the URS1 motif during vegetative growth and induced during meiotic prophase by the UASH motif in cooperation with the bifunctional URS1 site, which is required for full induction of HOP1. While URS1 is bound in vitro by the Buf and Ume6 repressor proteins, we demonstrate for the first time by electrophoretic mobility shift assays and interference footprinting that the UASH site interacts in vitro with a novel factor called UBF (UASH binding factor) which is present in haploid and diploid cycling, as well as sporulating cells. Point mutations in the HOP1 UASH motif abolish UBF-dependent DNA binding activity in vitro and meiotic HOP1 gene expression in vivo. Furthermore, we show that UBF binds in vitro to UASH-like sequences in the promoter regions of several meiosis-specific and non-specific genes and propose that UBF mediates gene expression through its interaction with the UASH motif in both cycling and sporulating cells.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Meiose , Mitose , Proteínas Pol1 do Complexo de Iniciação de Transcrição , Regiões Promotoras Genéticas , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Fatores de Transcrição/metabolismo , Sequência de Bases , Sequência Consenso , Proteínas Fúngicas/metabolismo , Genes Fúngicos , Dados de Sequência Molecular , Proteínas Nucleares/genética , Oligodesoxirribonucleotídeos/química , Mutação Puntual , RNA Mensageiro/genética , Saccharomyces cerevisiae/citologia , Esporos Fúngicos
18.
Glia ; 31(1): 51-8, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10816606

RESUMO

In various neurologic diseases, astrocytes express interleukin-6 (IL-6), which is an endogenous pyrogen, a neuroprotective factor, and a regulator of the blood-brain barrier. The expression of IL-6 in astrocytes is stimulated by extracellular adenosine through A(2B) receptors. To investigate the signaling cascade that induces IL-6 gene transcription further, we transfected primary mouse astrocytes with a reporter gene construct, in which luciferase expression is directed by the human IL-6 promoter. Expression of PKI, an inhibitor of protein kinase A (PKA), interfered with IL-6 transcription indicating that PKA mediates the effect of adenosine. The CAAT box of the IL-6 promoter is necessary for the stimulation by adenosine as a mutation in this element reduced the stimulation by adenosine. Indeed, the cAMP agonist forskolin increased the binding of the transcription factors NF-IL-6 and C/EBPdelta to the CAAT box of the IL-6 promoter in nuclear extracts of astrocytes. Inhibition of the de novo synthesis of NF-IL-6 by cycloheximide or an antisense oligonucleotide reduced the enhancement of NF-IL-6 binding to the CAAT box and inhibited stimulation of IL-6 transcription by forskolin. In addition, overexpression of NF-IL-6 induced IL-6 transcription. This suggests that adenosine induces the de novo synthesis of NF-IL-6 through activation of PKA and thereby stimulates transcription of IL-6 in astrocytes.


Assuntos
Adenosina/farmacologia , Astrócitos/fisiologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas de Ligação a DNA/metabolismo , Expressão Gênica/efeitos dos fármacos , Interleucina-6/genética , Proteínas Nucleares/metabolismo , Animais , Astrócitos/metabolismo , Sequência de Bases/genética , Proteínas Estimuladoras de Ligação a CCAAT , Células Cultivadas , Colforsina/farmacologia , AMP Cíclico/agonistas , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/fisiologia , Humanos , Camundongos , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/fisiologia , Oligonucleotídeos Antissenso/farmacologia , Regiões Promotoras Genéticas/genética , Regiões Promotoras Genéticas/fisiologia , Distribuição Tecidual , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/fisiologia , Ativação Transcricional/fisiologia , Transfecção
19.
Mol Cell ; 2(6): 709-18, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9885559

RESUMO

Exit from mitosis requires the inactivation of mitotic cyclin-dependent kinases (CDKs) by an unknown mechanism. We show that the Cdc14 phosphatase triggers mitotic exit by three parallel mechanisms, each of which inhibits Cdk activity. Cdc14 dephosphorylates Sic1, a Cdk inhibitor, and Swi5, a transcription factor for SIC1, and induces degradation of mitotic cyclins, likely by dephosphorylating the activator of mitotic cyclin degradation, Cdh1/Hct1. Feedback between these pathways may lead to precipitous collapse of mitotic CDK activity and help coordinate exit from mitosis.


Assuntos
Proteínas de Ciclo Celular/fisiologia , Ciclina B , Quinases Ciclina-Dependentes/metabolismo , Proteínas de Ligação a DNA , Mitose/fisiologia , Proteínas Tirosina Fosfatases , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/enzimologia , Complexos Ubiquitina-Proteína Ligase , Ciclossomo-Complexo Promotor de Anáfase , Proteínas Cdh1 , Proteínas de Ciclo Celular/genética , Proteínas Inibidoras de Quinase Dependente de Ciclina , Ciclinas/metabolismo , Replicação do DNA/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/fisiologia , Proteínas de Ligação ao GTP , Regulação Enzimológica da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Ligases/metabolismo , Ligases/fisiologia , Mutação , Fosfoproteínas Fosfatases/genética , Fosfoproteínas Fosfatases/fisiologia , Fosforilação , Proteínas Quinases/fisiologia , Proteínas Serina-Treonina Quinases , Proteínas de Ligação a RNA , Proteínas Recombinantes de Fusão/genética , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Especificidade por Substrato , Fatores de Transcrição/metabolismo , Transcrição Gênica , Ubiquitina-Proteína Ligases
20.
J Neurochem ; 73(4): 1461-6, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10501190

RESUMO

Bradykinin, a mediator of inflammation, is produced in the brain during trauma and stroke. It is thought to open the blood-brain barrier, although the mechanism is unclear. We have investigated, therefore, the effect of bradykinin on the expression of interleukin-6 (IL-6), a putative modulator of the blood-brain barrier, in astrocytes. IL-6 gene transcription was evaluated by transient transfection of the human IL-6 promoter linked to the luciferase gene. In murine astrocytes, bradykinin stimulated IL-6 secretion and gene transcription. The effect of bradykinin was blocked by KN-93, an inhibitor of Ca2+/calmodulin-dependent protein kinases, and by bisindolylmaleimide I, an inhibitor of protein kinase C, suggesting the involvement of these protein kinases. Mutations in the multiple response element and the binding site for nuclear factor-kappaB (NF-kappaB), but not in other known elements of the IL-6 promoter, interfered with induction of IL-6 transcription. The involvement of NF-kappaB was supported further by the finding that overexpression of nmIkappaB alpha, a stable inhibitor of NF-kappaB, inhibited the induction of IL-6 by bradykinin. Bradykinin activated NF-kappaB in primary astrocytes as shown by increased DNA binding of NF-kappaB. These data demonstrate that bradykinin stimulates IL-6 expression through activation of NF-kappaB, which may explain several inflammatory effects of bradykinin.


Assuntos
Astrócitos/fisiologia , Bradicinina/farmacologia , Regulação da Expressão Gênica/fisiologia , Interleucina-6/genética , NF-kappa B/metabolismo , Transcrição Gênica , Animais , Animais Recém-Nascidos , Benzilaminas/farmacologia , Encéfalo/citologia , Encéfalo/fisiologia , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Indóis/farmacologia , Cinética , Luciferases/genética , Maleimidas/farmacologia , Camundongos , Regiões Promotoras Genéticas , Proteína Quinase C/metabolismo , Proteínas Recombinantes de Fusão/biossíntese , Sulfonamidas/farmacologia , Acetato de Tetradecanoilforbol/farmacologia , Tapsigargina/farmacologia , Transcrição Gênica/efeitos dos fármacos , Transfecção
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