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1.
Phys Rev E ; 109(2-2): 025202, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38491663

RESUMO

The properties of plasmas in the low-density limit are described by virial expansions. Analytical expressions are known from Green's function approaches only for the first three virial coefficients. Accurate path-integral Monte Carlo (PIMC) simulations have recently been performed for the uniform electron gas, allowing the virial expansions to be analyzed and interpolation formulas to be derived. The exact expression for the second virial coefficient is used to test the accuracy of the PIMC simulations and the range of validity of the interpolation formula of Groth et al. [Phys. Rev. Lett. 119, 135001 (2017)0031-900710.1103/PhysRevLett.119.135001], and we discuss the fourth virial coefficient, which is not exactly known yet. Combining PIMC simulations with benchmarks from exact virial expansion results would allow us to obtain more accurate representations of the equation of state for parameter ranges of conditions which are of interest, e.g., for helioseismology.

2.
Herz ; 45(4): 362-368, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30054714

RESUMO

BACKGROUND: The possible treatment strategies for defects of the pace-sense (P/S) part of a defibrillation lead are either implantation of a new high-voltage (HV)-P/S lead, with or without extraction of the malfunctioning lead, or implantation of a P/S lead. METHODS: We conducted a Web-based survey across cardiac implantable electronic device (CIED) centers to investigate their procedural practice and decision-making process in cases of failure of the P/S portion of defibrillation leads. In particular, we focused on the question of whether the integrity of the HV circuit is confirmed by a test shock before decision-making. The questionnaire included 14 questions and was sent to 951 German, 341 Austrian, and 120 Swiss centers. RESULTS: The survey was completed by 183 of the 1412 centers surveyed (12.7% response rate). Most centers (90.2%) do not conduct a test shock to confirm the integrity of the HV circuit before decision-making. Procedural practice in lead management varies depending on the presentation of lead failure and whether the center applies a test shock. In centers that do not conduct a test shock, the majority (69.9%) implant a new HV-P/S lead. Most centers (61.7%) that test the integrity of the HV system implant a P/S lead. The majority of centers favor DF-4 connectors (74.1%) over DF-1 connectors (25.9%) at first CIED implantation. CONCLUSION: Either implanting a new HV-P/S lead or placing an additional P/S lead are selected strategies if the implantable cardioverter-defibrillator lead failure is localized to the P/S portion. However, conducting a test shock to confirm the integrity of the HV component is rarely performed.


Assuntos
Desfibriladores Implantáveis , Cardioversão Elétrica , Padrões de Prática Médica , Áustria , Alemanha , Inquéritos e Questionários , Suíça
3.
Eur J Endocrinol ; 181(1): 79-91, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31100717

RESUMO

OBJECTIVE: Growth hormone (GH) deficiency is related to increased cardiovascular mortality. We studied clinical status, concentration of amino-terminal-pro B-type natriuretic-peptide (NT-proBNP) and echocardiographic parameters during long-term GH replacement (GH-R). METHODS: Fifty-one patients (29 females), 45.9 ± 11.3 years (mean ± s.d.), median follow-up 36.2 months, echocardiography and laboratory determinations initially and at 12-months intervals. RESULTS: At the last follow-up (last observation carried forward) (LFU (LOCF)) insulin-like growth-factor-1 standard deviation score (IGF-1 SDS) was ±1 in 92% of the patients. The median NT-proBNP declined significantly and stabilized (-40.5%) at LFU (LOCF) due to patients with a basal NT-proBNP >125 ng/L (indicative of heart failure). The basal NT-proBNP and the final IGF-1 SDS were significant predictors of the NT-proBNP at LFU (LOCF). Initially left ventricular enddiastolic diameter (LVEDD), left ventricular posterior wall diameter (LVPWD) and ejection fraction (EF) were normal, while interventricular septum diameter (IVSD) and left ventricular mass index (LVMi) were slightly increased. LVPWD and IVSD had significantly declined by year three. The LVMi was moderately to severely abnormal in 37.3 and 52.0% of patients initially and at LFU (LOCF). At LFU (LOCF) LVMi and IGF-1 were significantly correlated in the 14 male patients of this subgroup. CONCLUSION: Long-term GH-R of GHD positively affected ISVD and LVPWD. In a subgroup of patients with severe GHD, LVMi increased concomitantly to the decline in NT-proBNP and this was positively correlated to the final IGF-1 concentration. Whether this observation indicates a positive development in a structurally altered heart muscle (reversal of adverse remodelling) or poses a future risk for heart failure needs further follow-up.


Assuntos
Hormônio do Crescimento/administração & dosagem , Insuficiência Cardíaca/etiologia , Terapia de Reposição Hormonal/métodos , Hormônio do Crescimento Humano/deficiência , Fatores de Tempo , Adulto , Esquema de Medicação , Ecocardiografia , Feminino , Seguimentos , Coração/efeitos dos fármacos , Humanos , Fator de Crescimento Insulin-Like I/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Resultado do Tratamento
5.
Phys Rev Lett ; 104(20): 202501, 2010 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-20867023

RESUMO

The symmetry energy of nuclear matter is a fundamental ingredient in the investigation of exotic nuclei, heavy-ion collisions, and astrophysical phenomena. New data from heavy-ion collisions can be used to extract the free symmetry energy and the internal symmetry energy at subsaturation densities and temperatures below 10 MeV. Conventional theoretical calculations of the symmetry energy based on mean-field approaches fail to give the correct low-temperature, low-density limit that is governed by correlations, in particular, by the appearance of bound states. A recently developed quantum-statistical approach that takes the formation of clusters into account predicts symmetry energies that are in very good agreement with the experimental data. A consistent description of the symmetry energy is given that joins the correct low-density limit with quasiparticle approaches valid near the saturation density.

8.
Nature ; 445(7125): E7-8; discussion E8, 2007 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-17230145

RESUMO

In a theoretical interpretation of observational data from the neutron star EXO 0748-676, Ozel concludes that quark matter probably does not exist in the centre of neutron stars. However, this conclusion is based on a limited set of possible equations of state for quark matter. Here we compare Ozel's observational limits with predictions based on a more comprehensive set of proposed quark-matter equations of state from the literature, and conclude that the presence of quark matter in EXO 0748-676 is not ruled out.

9.
Phys Rev Lett ; 96(14): 140402, 2006 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-16712053

RESUMO

Electron-positron pair creation in a standing wave is explored using a parameter-free quantum kinetic equation. Field strengths and frequencies corresponding to modern optical lasers induce a material polarization of the QED vacuum, which may be characterized as a plasma of e+e- quasiparticle pairs with a density of approximately 10(20) cm-3. The plasma vanishes almost completely when the laser field is zero, leaving a very small residual pair density n(r) which is the true manifestation of vacuum decay. The average pair density per period is proportional to the laser intensity but independent of the frequency nu. The density of residual pairs also grows with laser intensity but n(r) proportional to nu(2). With optical lasers at the forefront of the current generation, these dynamical QED vacuum effects can plausibly generate 5-10 observable two-photon annihilation events per laser pulse.

10.
Cell ; 89(1): 55-62, 1997 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-9094714

RESUMO

We examine transcriptional activation and chromatin remodeling at the PHO5 promoter in yeast by fusion proteins that are thought to act by recruiting the RNA polymerase II holoenzyme to DNA in the absence of a classic activating region. These hybrid proteins (e.g., Gal11+Pho4 or Gal4(58-97)+Pho4 in the presence of a GAL11P allele) efficiently activated transcription and remodeled chromatin. Similar chromatin remodeling was observed at a PHO5 promoter deleted for TATA and thus unable to support transcription. We conclude that recruitment of the holoenzyme or associated proteins suffices for chromatin remodeling. We also show that the SWI/SNF complex is required neither for efficient transcription of the wild-type PHO5 nor the GAL1 promoters, and we observe nearly complete chromatin remodeling at PHO5 in the absence of Snf2.


Assuntos
Cromatina/metabolismo , Regiões Promotoras Genéticas/fisiologia , RNA Polimerase II/metabolismo , Proteínas de Saccharomyces cerevisiae , Proteínas de Ligação a DNA , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica/fisiologia , Complexo Mediador , Proteínas Recombinantes de Fusão/genética , TATA Box/genética , Transativadores/genética , Fatores de Transcrição/genética , Transcrição Gênica/fisiologia , Leveduras/genética
11.
Phys Rev Lett ; 77(18): 3724-3727, 1996 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-10062292
13.
15.
Biochim Biophys Acta ; 1217(2): 188-94, 1994 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-8110833

RESUMO

From the analysis of two overlapping cosmid clones prepared from human genomic DNA libraries, a contig of 44 kb containing a 5' portion of the PAP gene and 17 kb of the upstream region was established. It was characterized by restriction mapping and sequence analysis of 2.5 kb upstream of the initiation codon. Two major transcription initiation sites were found to be located around 56 and 91 bp upstream of the initiation codon, as determined by nuclease S1 and primer extension mapping. Expression of the PAP gene was measured by Northern blots in the androgen responsive LNCaP cell line. It was found to be induced 2-3-fold by the addition of the synthetic androgen mibolerone to the cells. The induced mRNA levels were approx. 10-times lower than those for the prostate-specific antigen (PSA) in LNCaP cells.


Assuntos
Fosfatase Ácida/genética , Regiões Promotoras Genéticas , Próstata/enzimologia , Sequência de Aminoácidos , Androgênios/farmacologia , Sequência de Bases , Linhagem Celular , Clonagem Molecular , Regulação da Expressão Gênica , Humanos , Masculino , Dados de Sequência Molecular , RNA Mensageiro/análise , Transcrição Gênica/efeitos dos fármacos
16.
Mol Endocrinol ; 7(7): 924-36, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8413317

RESUMO

Autoregulation is a control mechanism common to several proteins of the steroid/thyroid hormone receptor superfamily. In this work, the effect of androgens and antiandrogens on the expression of the human androgen receptor (hAR) in prostate and breast cancer cell lines was studied. Northern blot analysis revealed a decrease in hAR steady state RNA levels in LNCaP cells by 3.3 nM of the synthetic androgen mibolerone. Maximal down-regulation of hAR RNA to 30% of control levels occurred 48 h after hormone addition. T47D breast cancer cells showed a similar effect with mibolerone, while hAR expression in normal skin fibroblasts did not respond to androgen treatment. As shown by nuclease S1 analysis, hAR transcripts initiate at three principal start sites, all of which are equally sensitive to androgen. Steroidal as well as nonsteroidal antiandrogens were capable of partially antagonizing androgen-mediated hAR RNA down-regulation in LNCaP and T47D cells, while not exerting a significant effect when administered alone. While hAR RNA stability was increased by hormone, nuclear run-on analysis revealed a 4-fold reduction of hAR gene transcription 96 h after androgen treatment. Although decreased hAR RNA levels did not coincide with a parallel decrease in AR protein levels, analysis of androgen-inducible reporter constructs demonstrated that prolonged androgen administration to cells results in a progressively impaired sensitivity of the intracellular androgen response mechanism. These results show that prolonged androgen exposure leads, besides its effect on hAR RNA levels, to functional inactivation of the AR. Thus, in vivo, posttranslational control of AR activity appears to be a novel mechanism of negative autoregulation of androgen effects on gene expression.


Assuntos
Androgênios/farmacologia , Regulação da Expressão Gênica/genética , Processamento de Proteína Pós-Traducional/fisiologia , Receptores Androgênicos/análise , Receptores Androgênicos/genética , Transcrição Gênica/fisiologia , Androgênios/imunologia , Anticorpos/imunologia , Anticorpos/farmacologia , Sequência de Bases , Northern Blotting , Neoplasias da Mama/química , Neoplasias da Mama/patologia , Neoplasias da Mama/ultraestrutura , Células Cultivadas , Regulação para Baixo , Fibroblastos/química , Fibroblastos/citologia , Fibroblastos/ultraestrutura , Humanos , Imuno-Histoquímica , Masculino , Dados de Sequência Molecular , Nandrolona/análogos & derivados , Nandrolona/farmacologia , Neoplasias da Próstata/química , Neoplasias da Próstata/patologia , Neoplasias da Próstata/ultraestrutura , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/genética , RNA Mensageiro/análise , RNA Mensageiro/genética , Receptores Androgênicos/fisiologia , Fatores de Tempo , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/genética , Transfecção , Células Tumorais Cultivadas
17.
Rehabilitation (Stuttg) ; 29(2): 76-83, 1990 May.
Artigo em Alemão | MEDLINE | ID: mdl-2142326

RESUMO

Presented are the findings of vocational training data analysis concerning the 91,241 disabled young people who had entered vocational training in the period 1982-87 carried by the Federal Employment Institute within the scope of "Anordnung Rehabilitation" (AReha). 77% of the young rehabilitees successfully concluded their vocational training at the first attempt; 22% dropped out, and 2% failed at the exams. Of those who had dropped out prematurely, some 39% participated in other types of vocational rehabilitation measures; no data are contained in the statistics concerning the whereabouts of the remainder. The majority of the young people, i.e. 77%, underwent vocational training in a recognized training occupation, the others in line with section 48 BBiG (vocational education act) or section 42 b HwO (handicrafts ordinance) to reduced requirements. 61% of the training measures were industrial ones, 23% provided in a vocational training centre, and the remaining 16% in some other non-industrial rehabilitation facility. The greatest single population among the young rehabilitees were those with learning disabilities, with a share of 63%. The Federal Employment Institute's statistics containing no data beyond the termination of training, information relative to vocational integration after training completion could only be gained on the basis of other, empirical investigations.


Assuntos
Pessoas com Deficiência/educação , Reabilitação Vocacional , Educação Vocacional , Adolescente , Adulto , Pessoas com Deficiência/estatística & dados numéricos , Feminino , Alemanha Ocidental , Humanos , Deficiências da Aprendizagem/reabilitação , Masculino , Centros de Reabilitação , Reabilitação Vocacional/estatística & dados numéricos , Socialização
18.
Pharmacopsychiatry ; 22(3): 120-5, 1989 May.
Artigo em Inglês | MEDLINE | ID: mdl-2568645

RESUMO

The therapeutic efficacy and tolerance of metaclazepam and diazepam were compared in a double-blind study of outpatients suffering from a generalized anxiety syndrome. The investigators were general practitioners. A total of 168 male and female patients aged between 18 and 60 years were included in the study and received either 15 mg metaclazepam or 15 mg diazepam per day. The analysis of tolerance was made for all 168 included patients, the evaluation of efficacy is based on the results of 131 patients (42 males and 89 females) with valid data over four weeks. During the four-week therapy period four examinations were made on days 0, 7, 14, and 28. A significant improvement of the severity of illness after administering the drugs was found for both drugs in the Clinical Global Impressions (CGI), in the Hamilton Anxiety Scale (HAMA), in the List of Complaints (B-L), and in the Adjective Checklist (EWL-K). Metaclazepam showed a statistically significant superiority over diazepam as far as the CGI items "severity of illness" and "global improvement" were concerned. Metaclazepam was slightly superior to diazepam in the two HAMA subscales "psychic anxiety" and "somatic anxiety". In the items of the selfrating scales (B-L and EWL-K) the therapeutic results of the metaclazepam group were, almost without exception, better than those of the diazepam group. A comparison of tolerance showed that metaclazepam was better tolerated. This can be seen in the greater frequency of side effects like tiredness and drowsiness under diazepam. Especially at the beginning of treatment, tiredness and drowsiness were recorded 2 1/2 times more frequently for the patients on diazepam than for those on metaclazepam.


Assuntos
Ansiolíticos/uso terapêutico , Ansiedade/tratamento farmacológico , Benzodiazepinas/uso terapêutico , Diazepam/uso terapêutico , Adolescente , Adulto , Ansiolíticos/administração & dosagem , Ansiolíticos/efeitos adversos , Ansiedade/psicologia , Benzodiazepinas/administração & dosagem , Benzodiazepinas/efeitos adversos , Pressão Sanguínea/efeitos dos fármacos , Ensaios Clínicos como Assunto , Diazepam/administração & dosagem , Diazepam/efeitos adversos , Método Duplo-Cego , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Escalas de Graduação Psiquiátrica , Distribuição Aleatória
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