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1.
Phys Rev Lett ; 123(8): 080503, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31491201

RESUMO

Magic states were introduced in the context of Clifford circuits as a resource that elevates classically simulatable computations to quantum universal capability, while maintaining the same gate set. Here we study magic states in the context of matchgate (MG) circuits, where the notion becomes more subtle, as MGs are subject to locality constraints. Nevertheless a similar picture of gate-gadget constructions applies, and we show that every pure fermionic state which is non-Gaussian, i.e., which cannot be generated by MGs from a computational basis state, is a magic state for MG computations. This result has significance for prospective quantum computing implementation in view of the fact that MG circuit evolutions coincide with the quantum physical evolution of noninteracting fermions.

2.
Acta Physiol Hung ; 102(3): 301-10, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26551746

RESUMO

We examined the effects of different shift work schedules and chronic mild stress (CMS) on mood using animal model. The most common international shift work schedules in nursing were applied by three groups of Wistar-rats and a control group with normal light-dark cycle. One subgroup from each group was subjected to CMS. Levels of anxiety and emotional life were evaluated in light-dark box. Differences between the groups according to independent and dependent variables were examined with one- and two-way analysis of variance, with a significance level defined at p < 0.05. Interaction of lighting regimen and CMS was proved to be significant according to time spent in the light compartment and the average number of changes between the light and dark compartments. Results of our examination confirm that the changes of lighting conditions evocate anxiety more prominently than CMS. No significant differences were found between the results of the low rotating group and the control group, supposing that this schedule is the least harmful to health. Our results on the association between the use of lighting regimens and the level of CMS provide evidence that the fast rotating shift work schedule puts the heaviest load on the organism of animals.


Assuntos
Comportamento Animal , Abrigo para Animais , Iluminação/métodos , Estresse Psicológico/psicologia , Animais , Ansiedade/etiologia , Ansiedade/psicologia , Emoções , Atividade Motora , Fotoperíodo , Ratos Wistar , Índice de Gravidade de Doença , Estresse Psicológico/diagnóstico , Estresse Psicológico/etiologia , Fatores de Tempo
3.
Artigo em Alemão | MEDLINE | ID: mdl-20198357

RESUMO

The authors differentiates deviant (paraphilic) and non-deviant forms of a sexual addictive symptomatology. For the non-deviant forms, the diagnostic term paraphilia-related disorder is used. According to etiological factors, the authors discuss an interaction of a biological vulnerability, attachment and relationship problems, disorders of affect regulation as well as disinhibition of sexual excitation. Some individuals react to negative emotions, like depression or anxiety, with an increased sexual arousal. They may try to cope with negative emotions by being sexually active. However, the importance of the sexual stimulus itself should not be ignored. The authors describe specific psychotherapy, the attendance of self-help groups, and pharmacological treatment, especially with selective serotonin reuptake inhibitors.


Assuntos
Comportamento Aditivo/terapia , Psicoterapia/métodos , Comportamento Sexual/psicologia , Comportamento Aditivo/diagnóstico , Comportamento Aditivo/psicologia , Humanos
4.
Stress ; 12(2): 115-24, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18850494

RESUMO

Period 2 (Per2) is an important clock gene involved in the regulation of the major circadian clock in the mammalian central nervous system, the suprachiasmatic nucleus. In addition, Per2 is expressed in many other stress-sensitive brain structures. We have previously showed that the non-preganglionic Edinger-Westphal nucleus (npEW) is the main site of the corticotropin-releasing factor peptide family member urocortin 1 (Ucn1) and that this peptide undergoes conspicuous expression changes in response to various stressors. Here, we hypothesized that in the rat npEW both Per2 and Ucn1 would be produced in a diurnal, rhythmical fashion. This hypothesis was tested by following this expected rhythm on two days in rats killed at four time points each day (Zeitgeber times 0, 6, 12, and 18). We showed the co-existence of Per2 and Ucn1 in the npEW with double-label immunofluorescence and demonstrated with quantitative RT-PCR and semi-quantitative immunocytochemistry diurnal rhythms in Per2 mRNA expression and Per2 protein content, each on a single different day, with a minimum at lights-off and a maximum at lights-on. We furthermore revealed a diurnal rhythm in the number of Ucn1-immunopositive neurones and in their Ucn1 peptide content, with a minimum at night and at the beginning of the light period and a peak at lights-off, while the Ucn1 mRNA content paralleled the Per2 mRNA rhythm. The rhythms were accompanied by a diurnal rhythm in plasma corticosterone concentration. Our results are in line with the hypothesis that both Per2 and Ucn1 in the rat npEW are produced in a diurnal fashion, a phenomenon that may be relevant for the regulation of the diurnal rhythm in the stress response.


Assuntos
Proteínas de Ciclo Celular/biossíntese , Aqueduto do Mesencéfalo/metabolismo , Ritmo Circadiano/fisiologia , Neurônios/metabolismo , Proteínas Nucleares/biossíntese , Urocortinas/biossíntese , Animais , Corticosterona/sangue , Imuno-Histoquímica , Masculino , Proteínas Circadianas Period , Ratos , Ratos Wistar
5.
Neurotox Res ; 13(2): 85-96, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18515211

RESUMO

While certain circadian hormonal changes are prominent, their predictable assessment requires a standardization of conditions of sampling. The 24-hour rhythm in circulating corticosterone of rodents, known since the 1950s, was studied as a presumed proxy for stress on 108 rats divided into 9 groups of 6 male and 9 groups of 6 female animals sampled every 4 hours for 24 hours. In a first stress study, the "no-rhythm" (zero-amplitude) assumption failed to be rejected at the 5% probability level in the two control groups and in 16 out of the 18 groups considered. A circadian rhythm could be detected with statistical significance, however, in three separate follow-up studies in the same laboratory, each on 168 rats kept on two antiphasic lighting regimens, with 4-hourly sampling for 7 or 14 days. In the first stress study, pooling of certain groups helped the detection and assessment of the circadian corticosterone rhythm. Without extrapolating to hormones other than corticosterone, which may shift more slowly or adjust differently and in response to different synchronizers, the three follow-up studies yielded uncertainty measures (95% confidence intervals) for the point estimate of its circadian period, of possible use in any future study as a reference standard. The happenstance of a magnetic disturbance at the start of two follow-up studies was associated with the detection of a circasemiseptan component, raising the question whether a geomagnetic disturbance could be considered as a "load". Far beyond the limitations of sample size, the methodological requirements for standardization in the experimental laboratory concerning designs of studies are considered in the context of models of depression. Lessons from nature's unforeseen geomagnetic contribution and from human studies are noted, all to support the advocacy, in the study of loads, of sampling schedules covering more than 24 hours.


Assuntos
Transtornos Cronobiológicos/fisiopatologia , Corticosterona/sangue , Depressão/fisiopatologia , Campos Eletromagnéticos , Estresse Fisiológico/fisiopatologia , Animais , Peso Corporal , Transtornos Cronobiológicos/metabolismo , Ritmo Circadiano/fisiologia , Depressão/metabolismo , Sacarose Alimentar/farmacologia , Modelos Animais de Doenças , Feminino , Privação de Alimentos/fisiologia , Humanos , Iluminação , Masculino , Ratos , Ratos Wistar , Atividade Solar , Estresse Fisiológico/metabolismo , Testosterona/sangue , Privação de Água/fisiologia
6.
Gen Comp Endocrinol ; 152(2-3): 225-30, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17286974

RESUMO

Pituitary adenylate cyclase activating polypeptide (PACAP) is a pleiotropic neuropeptide exerting diverse actions in the central and peripheral nervous systems. A few studies indicate that PACAP is involved in the regulation of feeding and water homeostasis. The aim of the present study was to investigate changes in PACAP38 concentrations in different brain areas following food or water deprivation in male and female rats. Rats were sacrificed 12, 36 and 84h after water or food removal. PACAP levels were determined by radioimmunoassay. Our results show that levels of PACAP decreased in the hypothalamus in both sexes after water deprivation, with a more marked, significant decrease in females at 12h. A decrease was observed also in the telencephalon, with a similar pattern in both genders: levels were lowest after 12h, and showed a gradual increase at the other two time-points. PACAP levels increased in the brainstem of male rats, while females had a decrease 12h after water deprivation. The pattern of changes in PACAP levels was very different after food deprivation. In male rats, PACAP levels showed a significant increase in the hypothalamus, telencephalon and brainstem 12h after the beginning of starvation. In females, a less marked increase was observed only in the hypothalamus while no changes were found in the other brain areas. Our results show a sensitive reaction in changes of endogenous PACAP levels to water and food deprivation in most brain areas, but they are differentially regulated in male and female rats.


Assuntos
Privação de Alimentos/fisiologia , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Caracteres Sexuais , Privação de Água/fisiologia , Animais , Tronco Encefálico/metabolismo , Feminino , Homeostase/fisiologia , Hipotálamo/metabolismo , Masculino , Radioimunoensaio , Ratos , Ratos Wistar , Telencéfalo/metabolismo
7.
Gen Comp Endocrinol ; 153(1-3): 115-23, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17270184

RESUMO

Pituitary adenylate cyclase activating polypeptide (PACAP) is a widely distributed neuropeptide that has various different functions in the nervous system and in non-neural tissues. Little is known about the effects of PACAP in endothelial cells. The aim of the present study was to investigate the effects of PACAP on endothelial cell survival and apoptotic signaling pathways under oxidative stress. Mouse hemangioendothelioma (EOMA) cells were exposed to 0.5mM H(2)O(2) which resulted in a marked reduction of cell viability and a parallel increase of apoptotic cells assessed by MTT test and flow cytometry. Co-incubation with 20nM PACAP1-38 increased cell viability and reduced the percentage of apoptotic cells. Flow cytometry analysis showed that oxidative stress reduced the phosphorylation of the anti-apoptotic ERK and increased the phosphorylation of the pro-apoptotic JNK and p38 MAP kinases. PACAP1-38 treatment ameliorated these changes: levels of phospho-ERK were elevated and those of phospho-JNK and p38 were decreased. All these effects were abolished by simultaneous treatment with the PACAP antagonist PACAP6-38. In summary, our results show that PACAP effectively protects endothelial cells against the apoptosis-inducing effects of oxidative stress.


Assuntos
Apoptose/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Estresse Oxidativo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/farmacologia , Substâncias Protetoras/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Células Tumorais Cultivadas
8.
Biomed Pharmacother ; 59 Suppl 1: S109-16, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16275479

RESUMO

During 7 consecutive days, blood and several tissues were collected during daytime working hours only, three times per day at 4-h intervals from inbred Wistar rats, which had been previously standardized for 1 month in two rooms on a regimen of 12 h of light (L) alternating with 12 h of darkness (LD12:12). In one room, lights were on from 09:00 to 21:00 and in the other room, lights were on from 21:00 to 09:00 (DL12:12; reversed lighting regimen). This setup provides a convenient design to study circadian and extracircadian variations over long (e.g., 7-day) spans. Prior checking of certain circadian rhythms in animals reared in the room on reversed lighting (DL) as compared with animals in the usual (LD) regimen provided evidence that the 180 degrees phase-shift had occurred. These measurements were limited to the circadian (and not extended to infradian) variation. As marker rhythm, the core temperature of a subsample of rats was measured every 4 h around the clock (by night as well as by day) before the start of the 7-day sampling. An antiphase of the circadian rhythm in core temperature was thus demonstrated between rats in the LD vs. DL rooms. A sex difference in core temperature was also found in each room. A reversed rhythm in animals kept in DL and an antiphase between rats kept in DL vs. LD was again shown for the circulating corticosterone rhythm documented in subsamples of 8 animals of each sex sampled around the clock during the first approximately 1.5 day of the 7-day sampling. The findings were in keeping with the proposition that sampling rats at three timepoints 4 h apart during daytime from two rooms on opposite lighting regimens allows the assessment of circadian changes, the daytime samples from animals kept on the reversed lighting regimen accounting for the samples that would have to be obtained by night from animals kept in the room with the usual lighting regimen. During the 7-day-long follow-up, circadian and extracircadian spectral components were mapped for serum corticosterone, taking into account the large day-to-day variability. A third check on the synchronization of the animals to their respective lighting regimen was a comparison (and a good agreement) between studies carried out earlier on the same variables and the circadian results obtained on core temperature and serum corticosterone in this study as a whole. The present study happened to start on the day of the second extremum of a moderate double magnetic storm. The study of any associations of corticosterone with the storm is beyond our scope herein, as are the results on circulating prolactin, characterized by a greater variability and a larger sex difference than corticosterone. Sex differences and extracircadian aspects of prolactin and endothelin determined in the same samples are reported elsewhere, as are results on melatonin. Prior studies on melatonin were confirmed insofar as a circadian profile is concerned by sampling on two antiphasic lighting regimens, as also reported elsewhere. Accordingly, a circadian map for the rat will eventually be extended by the result of this study and aligned with other maps with the qualification of the unassessed contribution in this study of a magnetic storm.


Assuntos
Fenômenos Cronobiológicos , Ritmo Circadiano/fisiologia , Corticosterona/sangue , Glândulas Endócrinas/fisiologia , Hormônios/sangue , Animais , Temperatura Corporal/fisiologia , Peso Corporal/fisiologia , Campos Eletromagnéticos , Feminino , Iluminação , Modelos Lineares , Masculino , Melatonina/sangue , Dinâmica não Linear , Prolactina/sangue , Ratos , Caracteres Sexuais , Atividade Solar
9.
Biomed Pharmacother ; 59 Suppl 1: S209-12, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16275496

RESUMO

A circadian rhythm is documented in duodenal melatonin in rats, peaking 16.8 hours after light onset. This component is more readily detected after log10-transformation of the data. It differs between male and female rats, females having a larger circadian amplitude and an earlier acrophase. The circadian rhythm in duodenal melatonin is also found to lead that of pineal melatonin. The results are qualified by the presence at the start of mapping of the second extremum of a double magnetic storm.


Assuntos
Fenômenos Cronobiológicos , Ritmo Circadiano/fisiologia , Duodeno/metabolismo , Melatonina/metabolismo , Animais , Feminino , Luz , Masculino , Ratos , Ratos Wistar , Fatores Sexuais , Atividade Solar
10.
Biomed Pharmacother ; 59 Suppl 1: S213-9, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16275497

RESUMO

A circadian rhythm is documented for plasma, pineal, and hypothalamic melatonin of male and female rats kept on staggered lighting regimens. Log[_10]-transformation of the data usually normalizes, when need be, the distribution of residuals from the 24-hour cosine curve fits. A tentative circadian acrophase chart is presented that shows a lead in circadian acrophase of duodenal over pineal melatonin. The use of antiphasic lighting regimens facilitates circadian studies that can be carried out for several days, thereby allowing the assessment of infradian components such as a circasemiseptan variation in hypothalamic melatonin documented herein. The results are qualified by the presence of a second extremum of a double magnetic storm at the start of mapping.


Assuntos
Fenômenos Cronobiológicos , Ritmo Circadiano/fisiologia , Hipotálamo/metabolismo , Melatonina/metabolismo , Glândula Pineal/metabolismo , Animais , Feminino , Iluminação , Masculino , Melatonina/sangue , Ratos , Ratos Wistar , Reprodutibilidade dos Testes , Estações do Ano , Caracteres Sexuais
11.
Biomed Pharmacother ; 59 Suppl 1: S220-4, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16275498

RESUMO

In Göttingen, Germany, circadian variations in melatonin had been determined time-macroscopically in pineal glands, blood plasma and duodenum of chicken and rats. When these data were meta-analyzed, they agreed with the results from an independent survey on tissues from rats collected in a laboratory in Pécs, Hungary. In the latter study, tissues were analyzed chemically in Bratislava, Slovakia, and numerically in Minneapolis, MN, USA, all by single- and multiple-component cosinor and parameter tests. In rats and chickens, these inferential statistical procedures clearly demonstrated a lead in phase of the 24-h cosine curves best fitting all of the duodenal vs. those best fitting all of the pineal melatonin values in each species in 2 geographic (geomagnetic) locations. The 24-h cosine curve of circulating melatonin was found to be in an intermediate phase position. Mechanisms of the phase differences and the contribution of gastrointestinal melatonin to circulating hormone concentrations are discussed.


Assuntos
Fenômenos Cronobiológicos , Ritmo Circadiano/fisiologia , Duodeno/metabolismo , Melatonina/metabolismo , Glândula Pineal/metabolismo , Animais , Galinhas , Interpretação Estatística de Dados , Campos Eletromagnéticos , Geografia , Masculino , Melatonina/sangue , Ratos , Ratos Wistar
12.
Biomed Pharmacother ; 59 Suppl 1: S24-30, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16275503

RESUMO

A multi-center four-hourly sampling of many tissues for 7 days (00:00 on April 5-20:00 to April 11, 2004), on rats standardized for 1 month in two rooms on antiphasic lighting regimens happened to start on the day after the second extremum of a moderate double magnetic storm gauged by the planetary geomagnetic Kp index (which at each extremum reached 6.3 international [arbitrary] units) and by an equatorial index Dst falling to -112 and -81 nT, respectively, the latter on the first day of the sampling. Neuroendocrine chronomes (specifically circadian time structures) differed during magnetically affected and quiet days. The circadian melatonin rhythm had a lower MESOR and lower circadian amplitude and tended to advance in acrophase, while the MESOR and amplitude of the hypothalamic circadian melatonin rhythm were higher during the days with the storm. The circadian parameters of circulating corticosterone were more labile during the days including the storm than during the last three quiet days. Feedsidewards within the pineal-hypothalamic-adrenocortical network constitute a mechanism underlying physiological and probably also pathological associations of the brain and heart with magnetic storms. Investigators in many fields can gain from at least recording calendar dates in any publication so that freely available information on geomagnetic, solar and other physical environmental activity can be looked up. In planning studies and before starting, one may gain from consulting forecasts and the highly reliable nowcasts, respectively.


Assuntos
Fenômenos Cronobiológicos , Campos Eletromagnéticos , Sistemas Neurossecretores/fisiologia , Atividade Solar , Animais , Ritmo Circadiano , Retroalimentação , Hipotálamo/metabolismo , Iluminação , Melatonina/metabolismo , Glândula Pineal/metabolismo , Ratos , Ratos Wistar
13.
Peptides ; 22(9): 1371-7, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11514017

RESUMO

Levels of PACAP38 were measured in different areas of the chicken brain under various lighting conditions by radioimmunoassay (RIA). Selected groups of animals were maintained under light for 14 h alternating with 10 h of darkness (LD), reversed lighting conditions (DL) and constant light (LL) or constant dark (DD). Daily variations of PACAP levels were observed in the brainstem, diencephalon, telencephalon and retina. In the brainstem and diencephalon, levels of PACAP increased during subjective nighttime, except in the DL group where levels were elevated between 15-21 h. In the telencephalon, the lowest level of PACAP was measured between 12-21 h except in the DL group where two peaks occurred at 18 and 03 h. In the retina, all 4 groups showed a similar level and pattern, with lowest levels during midday hours. No daily variation was observed in the pineal gland. According to the present observations, it is suggested that PACAP levels differ in several areas of the chicken brain under various lighting conditions and photic stimuli do not appear to be the main regulators of the circadian variations of PACAP.


Assuntos
Encéfalo/metabolismo , Neuropeptídeos/metabolismo , Retina/fisiologia , Análise de Variância , Animais , Animais Recém-Nascidos , Encéfalo/anatomia & histologia , Galinhas , Ritmo Circadiano , Fotoperíodo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Radioimunoensaio , Retina/química , Fatores de Tempo , Distribuição Tecidual
14.
Phys Rev Lett ; 85(9): 2010-3, 2000 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-10970670

RESUMO

We demonstrate that two spatially separated parties (Alice and Bob) can utilize shared prior quantum entanglement, and classical communications, to establish a synchronized pair of atomic clocks. In contrast to classical synchronization schemes, the accuracy of our protocol is independent of Alice's or Bob's knowledge of their relative locations or of the properties of the intervening medium.

16.
Phys Rev A ; 54(6): 4707-4711, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9914035
17.
Phys Rev A ; 54(3): 1869-1876, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9913673
19.
Phys Rev Lett ; 76(15): 2818-2821, 1996 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-10060796
20.
Phys Rev Lett ; 74(20): 4083-4086, 1995 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-10058408
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