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1.
Hautarzt ; 70(11): 854-863, 2019 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-31584113

RESUMO

The project "Pain-free Hospital" was the first attempt to improve the level of postoperative care by standardizing pain therapy standards (concepts) in the individual surgical disciplines. Dermatosurgery is no exception. In addition to drug therapy, it is also important to consider biopsychosocial aspects of the symptom pain, as this is the only way to prevent chronification of acute pain in the further course of a disease. Drug therapy should not only be adapted to the classic WHO system (only considering pain intensity), but should also address aspects of pain quality. In this article, we discuss these aspects in more detail and present our treatment concept for dermatosurgery.


Assuntos
Procedimentos Cirúrgicos Dermatológicos , Manejo da Dor/métodos , Dor Pós-Operatória/terapia , Dor , Humanos , Medição da Dor
2.
Hautarzt ; 69(1): 48-57, 2018 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-28983646

RESUMO

In order to avoid chronification of pain, appropriate treatment has to be started as early as possible. Inpatient dermatology patients not only suffer from old age and associated multimorbidities but also from characteristic pain due to distinct dermatological diseases. In many cases clinicians have little experience with specific pain treatment but instead have many concerns about how to deal with analgesics. So far chronic pain has been treated according to the pain ladder of the World Health Organization (WHO), which prioritizes the intensity of pain. This article presents an easily implementable concept of pain therapy with special emphasis on the quality of pain. This provides information on whether it is neuropathic or nociceptive pain, which can ultimately be differentially treated. The primary aim is to provide treating dermatologists with a concept to assist in the initiation of an efficient and correct pain therapy. This brief introduction of an individualized pain treatment can reduce the risk of chronification of pain, which can severely impair the quality of life particularly in dermatology patients and also the frequent stigmatization due to the dermatosis.


Assuntos
Assistência Ambulatorial , Dermatologia , Dermatopatias/terapia , Analgésicos/uso terapêutico , Analgésicos Opioides/uso terapêutico , Dor Crônica/classificação , Dor Crônica/terapia , Quimioterapia Combinada , Intervenção Médica Precoce , Humanos , Neuralgia/classificação , Neuralgia/terapia , Dor Nociceptiva/classificação , Dor Nociceptiva/terapia , Medição da Dor , Dor Pós-Operatória/classificação , Dor Pós-Operatória/terapia , Equipe de Assistência ao Paciente , Encaminhamento e Consulta , Dermatopatias/classificação
3.
J Chem Phys ; 143(17): 174303, 2015 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-26547166

RESUMO

We present a systematic analysis of the ab initio controlled femtosecond spin dynamics in Ni3(CH3OH) and Co3(+)(CH3OH) clusters achieved by a spin-orbit-coupling enabled Λ process. The distortion caused by the attachment of CH3OH to one of the active magnetic centers of the Ni3 and the Co3(+) clusters induces asymmetric geometries which result in well localized spin densities on the magnetic centers. With the use of high-level quantum chemistry methods, successful spin-flip scenarios are demonstrated for both clusters. In order to assess the experimental accessibility of those effects, we compute their tolerance with respect to two laser pulse parameters, i.e., the energy detuning as well as the deviation of the polar angle ϕ from its optimized value. Finally, we calculate the magneto-optical Kerr effect in order to connect to the susceptibility tensor χ as an experimentally measurable quantity.

4.
Phys Rev Lett ; 109(26): 267209, 2012 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-23368615

RESUMO

We present a combined theoretical and experimental study of spin and charge dynamics on the homodinuclear compound [Ni2(II)(L-N4Me2)(emb)]. The theoretically calculated oscillator strengths of the ground-state absorption spectrum show an acceptable agreement with experiment. We predict a local ultrafast laser-induced spin-flip scenario, which involves charge-transfer states. Experimentally, we observe charge dynamics on two different time scales. The two relevant, transient electronic states and their electronic properties are also theoretically characterized. These results provide a joint investigation of the homodinuclear complex and suggest a realistic scenario for ultrafast spin dynamics and other optical-related manipulations.

5.
ChemistryOpen ; 11(5): e202100153, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34931474

RESUMO

We present a combined experimental and theoretical study of the ultrafast transient absorption spectroscopy results of a {Ni2 Dy2 }-compound in DMF, which can be considered as a prototypic molecule for single molecule magnets. We apply state-of-the-art ab initio quantum chemistry to quantitatively describe the optical properties of an inorganic complex system comprising ten atoms to form the chromophoric unit, which is further stabilized by surrounding ligands. Two different basis sets are used for the calculations to specifically identify two dominant peaks in the ground state. Furthermore, we theoretically propagate the compound's correlated many-body wavefunction under the influence of a laser pulse as well as relaxation processes and compare against the time-resolved absorption spectra. The experimental data can be described with a time constant of several hundreds of femtoseconds attributed to vibrational relaxation and trapping into states localized within the band gap. A second time constant is ascribed to the excited state while trap states show lifetimes on a longer timescale. The theoretical propagation is performed with the density-matrix formalism and the Lindblad superoperator, which couples the system to a thermal bath, allowing us to extract relaxation times from first principles.

6.
J Phys Chem A ; 115(10): 1774-80, 2011 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-21332233

RESUMO

We present a fully ab initio calculation, the synthesis and the characterization of the homodinuclear [Ni(2)(II)(L-N(4)Me(2))(emb)] complex, which can act as a prototypic, realistic substance for ultrafast laser-induced spin dynamics. The new compound, which has been synthesized and characterized, consists of two magnetic centers with different spin properties and different local symmetries (distorted octahedral versus distorted square-planar) and exhibits strong spin localization. We calculate the vibrational and electronic spectra of the compound and predict a local spin-flip scenario. The very existence and the properties of the compound represent an important step toward ultrafast experimental spin dynamics in ligand-stabilized multicenter compounds and paves the path toward laser-induced magnetic logic on a single molecule.

7.
J Phys Chem Lett ; 11(7): 2592-2597, 2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32163709

RESUMO

In this work, using ab initio many-body theory and inspired by an idea suggested by G. D. Mahan for an abstract N-dimensional chain composed of s-type atoms ( Phys. Rev. Lett. 2009, 102, 016801), we propose a functional topological spin-charge gearbox based on the real synthesized Co3Ni(EtOH) cluster driven with laser pulses. We analyze the implications arising from the use of a real molecule with d-character functional orbitals rather than an extended system and discuss the role of the point group symmetry of the system and the transferability of the electronic and spin density between different many-body states using specially designed laser pulses. We thus find that first-row transition-metal elements can host unpaired yet correlated d electrons and thus act as sites for spin information carriers, while designated laser pulses induce symmetry operations leading to a realizable spin-charge gearbox.

8.
Phys Rev Lett ; 103(21): 217401, 2009 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-20366066

RESUMO

In an ultrafast laser-induced magnetization-dynamics scenario we demonstrate for the first time an exact microscopic spin-switch mechanism. Combining ab initio electronic many-body theory and quantum optics analysis we show in detail how the coherently induced material polarization for every elementary process leads to angular-momentum exchange between the light and the irradiated antiferromagnetic NiO. Thus we answer the long-standing question where the angular momentum goes. The calculation also predicts a dynamic Kerr effect, which provides a signature for monitoring spin dynamics, by simply measuring the transient rotation and ellipticity of the reflected light.

9.
Mol Biol Cell ; 11(11): 3885-96, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11071914

RESUMO

The bidirectional nucleocytoplasmic transport of macromolecules is mediated by the nuclear pore complex (NPC) which, in yeast, is composed of approximately 30 different proteins (nucleoporins). Pre-embedding immunogold-electron microscopy revealed that Nic96p, an essential yeast nucleoporin, is located about the cytoplasmic and the nuclear periphery of the central channel, and near or at the distal ring of the yeast NPC. Genetic approaches further implicated Nic96p in nuclear protein import. To more specifically explore the potential role of Nic96p in nuclear protein import, we performed a two-hybrid screen with NIC96 as the bait against a yeast genomic library to identify transport factors and/or nucleoporins involved in nuclear protein import interacting with Nic96p. By doing so, we identified the yeast nucleoporin Nup53p, which also exhibits multiple locations within the yeast NPC and colocalizes with Nic96p in all its locations. Whereas Nup53p is directly involved in NLS-mediated protein import by its interaction with the yeast nuclear import receptor Kap95p, it appears not to participate in NES-dependent nuclear export.


Assuntos
Proteínas Fúngicas/metabolismo , Proteínas de Membrana , Complexo de Proteínas Formadoras de Poros Nucleares , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Porinas/genética , Porinas/metabolismo , Proteínas de Saccharomyces cerevisiae , Leveduras/metabolismo , Transporte Ativo do Núcleo Celular , Núcleo Celular/metabolismo , Núcleo Celular/ultraestrutura , Proteínas Fúngicas/genética , Deleção de Genes , Microscopia Imunoeletrônica , Mutação , Sinais de Localização Nuclear , Técnicas do Sistema de Duplo-Híbrido , Leveduras/genética , beta Carioferinas
10.
Biochim Biophys Acta ; 1466(1-2): 245-59, 2000 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10825446

RESUMO

The interaction of aqueous phospholipid dispersions of negatively charged 1,2-dimyristoyl-sn-glycero-3-phosphoglycerol, sodium salt (DMPG) with the divalent cations Mg(2+), Ca(2+) and Sr(2+) at equimolar ratios in 100 mM NaCl at pH 7 was investigated by Fourier transform infrared spectroscopy. The binding of the three cations induces a crystalline-like gel phase with highly ordered and rigid all-trans acyl chains. These features are observed after storage below room temperature for 24 h. When the gel phase is heated after prolonged incubation at low temperature phase transitions into the liquid crystalline phase are observed at 58 degrees C for the DMPG:Sr(2+), 65 degrees C for the DMPG:Mg(2+), and 80 degrees C for the DMPG:Ca(2+) complex. By subsequent cooling from temperatures above T(m) these complexes retain the features of a liquid crystalline phase with disordered acyl chains until a metastable gel phase is formed at temperatures between 38 and 32 degrees C. This phase is characterized by predominantly all-trans acyl chains, arranged in a loosely packed hexagonal or distorted hexagonal subcell lattice. Reheating the DMPG:Sr(2+) samples after a storage time of 2 h at 4 degrees C results in the transition of the metastable gel to the liquid crystalline phase at 35 degrees C. This phase transition into the liquid crystalline state at 35 degrees C is also observed for the Mg(2+) complex. However, for DMPG:Mg(2+) at higher temperatures, a partial recrystallization of the acyl chains occurs and the high temperature phase transition at 65 degrees C is also detected. In contrast, DMPG:Ca(2+) exhibits only the phase transition at 80 degrees C from the crystalline gel into the fluid state upon reheating. Below 20 degrees C, the rate of conversion from the metastable gel to a thermodynamically stable, crystalline-like gel phase decreases in the order Ca(2+)&z. Gt;Mg(2+)>Sr(2+). This conversion into the crystalline gel phase is accompanied by a complete dehydration of the phosphate groups in DMPG:Mg(2+) and by a reorientation of the polar lipid head groups in DMPG:Ca(2+) and in DMPG:Sr(2+). The primary binding sites of the cations are the PO(2)(-) groups of the phosphodiester moiety. Our infrared spectroscopic results suggest a deep penetration of the divalent cations into the polar head group region of DMPG bilayers, whereby the ester carbonyl groups, located in the interfacial region of the bilayers, are indirectly affected by strong hydrogen bonding of immobilized water molecules. In the liquid crystalline phase, the interaction of all three cations with DMPG is weak, but still observable in the infrared spectra of the DMPG:Ca(2+) complex by a slight ordering effect induced in the acyl chains, when compared to pure DMPG liposomes.


Assuntos
Cálcio/química , Magnésio/química , Fosfatidilgliceróis/química , Estrôncio/química , Cátions Bivalentes/química , Fosfatos/química , Fosfolipídeos/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
11.
Biochim Biophys Acta ; 1066(2): 166-74, 1991 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-1854782

RESUMO

Fourier transform infrared (FT-IR) spectroscopy was used to determine whether intramolecular hydrogen bonding between the C-OH and P-OH groups exists in beef heart cardiolipin (CL) or in hydrogenated beef heart cardiolipin (18:0-CL) as compared to the synthetic 2'-deoxy analogue of cardiolipin (16:0-dCL). Such intramolecular hydrogen bonding would provide a structural basis for proton conduction on the molecular level. In aqueous dispersions at 20 degrees C, both 18:0-CL and 16:0-dCL exist in the gel phase as bilayers with gel to liquid-crystalline transitions (Tm) at 61 and 56 degrees C, respectively, whereas the unsaturated CL exists in the non-bilayer (hexagonal II) state. Evidence for intramolecular hydrogen bonding of the C-OH group in aqueous dispersions of 18:0-CL is provided by the large increase in Tm observed on changing the aqueous medium from H2O to D2O but specific hydrogen-bonded C-OH...PO2- species cannot be identified because water molecules also compete for the PO2- binding sites. However, C-OH...PO2- hydrogen bonds can be identified in dry films of the sodium salt of 18:0-CL or in CCl4 solution. In contrast, such hydrogen bonds cannot be formed in the deoxy analogue (16:0-dCL) indicating that the central C-OH group in 18:0-CL could provide a structural basis for proton conduction, involving the phosphate groups.


Assuntos
Cardiolipinas/química , Ácidos Fosfatídicos/química , Amônia/química , Animais , Tetracloreto de Carbono/química , Bovinos , Análise de Fourier , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Substâncias Macromoleculares , Miocárdio/química , Selênio/química , Sódio/química , Espectrofotometria Infravermelho , Temperatura , Zinco/química
12.
Biochim Biophys Acta ; 1027(3): 229-37, 1990 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-2397234

RESUMO

The barotropic behavior of aqueous dispersions of two representative omega-cyclohexyl phosphatidylcholines was investigated by pressure-tuning Fourier transform infrared spectroscopy. In the even-numbered homologue, 1,2-di-14-cyclohexyltetradecanoyl-sn-glycero-3-phosphocholine (14cyPC), the lipid molecules are orientationally disordered until the applied pressure reaches 2.1 kbar. This pressure marks the onset of correlation field splitting of the scissoring and rocking modes of the linear chain methylenes, as well as that of the cyclohexyl ring methylenes. It indicates immobilization of the entire acyl chains, whereby the zig-zag planes of the neighboring straight chain all-trans methylenes are oriented mainly perpendicular to each other. As judged from the magnitude of the correlation field splittings, the interchain interaction is weaker in 14cyPC than that in linear lipids (e.g., DMPC or DPPC). Upon an increase in pressure, up to 20 kbar, the zig-zag methylene planes in 14cyPC undergo a gradual transformation to a parallel orientation. In the odd-numbered homologue, 1,2-di-13-cyclohexyltridecanoyl-sn-glycero-3-phosphocholine (13cyPC), there is no correlation field splitting originating from the straight chain methylenes (up to 21 kbar). The linear, nonbranched segments of the omega-cyclohexyl chains in 13cyPC are closely packed with the all-trans methylene zig-zag planes oriented parallel to each other. There is, however, correlation field splitting of the ring methylenes, indicating interring interactions between the bulky cyclohexyl rings in opposing bilayer leaflets. There are major structural differences between the even- and odd-numbered homologues in the interfacial region, which remain even at high pressures. The ester carbonyl C = O stretching band in 14cyPC is a composite of two discrete bands which do not change considerably in intensity or frequency in the pressure range 2-20 kbar. In contrast, 13cyPC possesses an additional, low-frequency C = O stretching component at low pressures. As the pressure increases, the three component bands coalesce into a single C = O stretching band. Our results suggest equally oriented, fully hydrogen-bonded carbonyl groups in 13cyPC at pressures above approx. 10 kbar.


Assuntos
Bicamadas Lipídicas/metabolismo , Fosfatidilcolinas/metabolismo , Análise de Fourier , Pressão Hidrostática , Espectrofotometria Infravermelho , Relação Estrutura-Atividade
13.
Biochim Biophys Acta ; 1294(2): 168-76, 1996 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-8645735

RESUMO

Variants of recombinant staphylokinase (Sak) were investigated by Fourier-transform infrared spectroscopy: Sak (wild type), Sak-M26A, Sak-M26L, and Sak-G34S/R36G/R43H (Sak-B). Estimation of the secondary structure and hydrogen-deuterium exchange experiments revealed the existence of fast-exchanging and strongly solvent-exposed fractions of the helical structures in the two samples Sak and Sak-M26L. These two samples are also thermally less stable with unfolding transition temperatures of 43.7 degrees C (Sak) and 43.5 degrees C (Sak-M26L), respectively. On contrast, Sak-M26A and Sak-G34S/R36G/R43H have a slower hydrogen-deuterium exchange, have a smaller solvent-exposed portion of the helical part, and are more resistant against thermal unfolding; the transition temperatures are 51.7 degrees C and 59.3 degrees C, respectively. The secondary structure analysis was performed by two different approaches, by curve-fitting after band narrowing and by pattern recognition (factor analysis) based upon reference spectra of proteins with known crystal structure. Within the limits of the used methods, we are unable to detect significant differences in the secondary structure of the four variants of Sak. According to the results of the factor analysis, the portions of secondary structure elements were obtained to 16-20% alpha-helix, 28-30% beta-sheet, 23-27% turns, 28-30% irregular (random) and other structure. The sharp differences in the specific plasminogen-activating capacity (Sak, Sak-G34S/R36G/R43H and Sak-M26L are fully active, but Sak-M26A does not form a stable complex with plasminogen) are not reflected in the structural features revealed by the infrared spectra of this study.


Assuntos
Metaloendopeptidases/química , Estrutura Secundária de Proteína , Deutério , Estabilidade Enzimática , Temperatura Alta , Hidrogênio , Metaloendopeptidases/biossíntese , Mutagênese Sítio-Dirigida , Mutação Puntual , Desnaturação Proteica , Dobramento de Proteína , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
14.
Int J Artif Organs ; 28(1): 66-73, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15742312

RESUMO

Fourier transform infrared microscopy was used to investigate human cortical bone samples before and after treatment with increasing doses of X-ray radiation. Especially the spectral region of the v1 and v3 phosphate vibrations of hydroxyapatite, the main mineral component of bone, and the region of the amide I and amide II vibrational bands due to the collagen extracellular matrix were examined. Major spectral changes in the phosphate region between 1250-1000 cm(-1) occur after irradiation doses between 1 and 4 Gray. These findings are explained by a decrease in size of mineral crystallites and by variances of the toichiometric/non-stoichiometric apatite composition. The Ca2+ /PO4(3-) /HPO4(2-) composition in the biological apatite is altered near the bone surface. The secondary structure of the collagen matrix is not affected by cumulative irradiation up to doses of 15 Gray as indicated by the unchanged frequency maximum and contour shape of the amide I band between 1600-1700 cm(-1) . However, side chain carboxylate groups of the collagen matrix that are involved in coordination with apatite bound calcium ions are partially removed by decarboxylation upon irradiation. Concomitantly, a loss of acidic phosphate groups due to a formation of phosphate groups with bound calcium is observed. These changes on a molecular level can be correlated with alterations in the mechanical properties of the bone samples, e.g. with an increased embrittlement as deduced from experiments with a scanning acoustic microscope.


Assuntos
Osso e Ossos/efeitos da radiação , Amidas/química , Amidas/efeitos da radiação , Osso e Ossos/química , Cálcio/química , Cálcio/efeitos da radiação , Ácidos Carboxílicos/química , Ácidos Carboxílicos/efeitos da radiação , Colágeno/química , Colágeno/efeitos da radiação , Cristalografia , Durapatita/química , Durapatita/efeitos da radiação , Humanos , Microespectrofotometria , Fosfatos/química , Fosfatos/efeitos da radiação , Doses de Radiação , Espectroscopia de Infravermelho com Transformada de Fourier , Raios X
15.
Urologe A ; 54(6): 887-99; quiz 900, 2015 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-26081822

RESUMO

Stress urinary incontinence in men is predominantly iatrogenic whereby radical prostatectomy is the most common cause with persistent stress urinary incontinence rates varying between 10 % and 25 %. The first line therapy for postoperative male stress urinary incontinence is physiotherapy, especially pelvic floor muscle rehabilitation. If conservative treatment fails to show sufficient improvement, surgical therapy is recommended. Several treatment options are currently available for the surgical treatment of male stress urinary incontinence including artificial sphincters, adjustable and functional sling systems, bulking agents and implantable balloon systems.


Assuntos
Terapia por Exercício/métodos , Prostatectomia/efeitos adversos , Slings Suburetrais , Incontinência Urinária por Estresse/etiologia , Incontinência Urinária por Estresse/terapia , Esfíncter Urinário Artificial , Medicina Baseada em Evidências , Humanos , Masculino , Resultado do Tratamento
16.
Eur J Cell Biol ; 78(4): 278-87, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10350216

RESUMO

In a yeast two-hybrid screen we identified an interaction between Drosophila lamin Dm0, a structural nuclear protein, and BICD, a protein involved in oocyte development. The interaction can be reconstituted in vitro and takes place between segments of both proteins predicted to form coiled coils. The affinity for lamin Dm0 of the minimal binding site on BICD is modulated in a complex fashion by other BICD segments. A point mutation, F684I, that causes the dominant, bicaudal, Bic-D phenotype inhibits lamin binding in the context of the minimal lamin-binding site, but not in a larger BICD fragment. The minimal lamin-binding site of BICD binds to a few other coiled-coil proteins, but binding to these proteins is not influenced by the F684I point mutation, suggesting that the interaction with lamin may play a role in Bic-D function. Our structural studies demonstrated that BICD is 60-70% alpha-helical, is a dimer, and consists of two parts: a thin rod-shaped part of about 32 nm, and a thicker rod-shaped part of about 26 nm. Likely, the thinner rod-shaped part of full-length BICD consists of the N-terminal half of the protein, and the lamin-binding site is located within the thicker rod-shaped part.


Assuntos
Proteínas de Drosophila , Drosophila/química , Proteínas de Insetos/química , Proteínas Nucleares/química , Animais , Proteínas de Insetos/ultraestrutura , Laminas , Modelos Biológicos , Fenótipo , Mutação Puntual , Ligação Proteica
17.
Biophys Chem ; 48(1): 61-74, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8257768

RESUMO

The complete thermodynamic profile for the non-intercalative binding of berenil to the alternating copolymer poly d(AT) and to the homopolymer poly (dA) x poly (dT) was investigated. Differential Scanning Calorimetry (DSC) and UV absorbance spectroscopy have been used to characterize and to compare the binding of berenil to the different synthetic polymers. Both double stranded DNA's show two types of binding; one stronger binding mode at low berenil concentrations and a weaker, in the case of poly d(AT)-berenil complexes slightly cooperative binding mode at higher drug to base pair ratios. For the interaction of berenil with poly d(AT) the thermodynamic data delta G(bind)0 = -33 kJ/mol drug, delta H(bind)0 = -29 kJ/mol of drug and delta S(bind)0 = +13 J/Kmol of drug were calculated. For the minor groove binding of berenil to poly (dA) x poly (dT) the following values were obtained: delta G(bind)0 = -34 kJ/mol of drug, delta H(bind)0 = -25 kJ/mol of drug and delta S(bind)0 = +30 J/Kmol of drug. Temperature-dependent UV absorbance spectroscopy revealed for both duplexes a biphasic "melting" behavior. However, the saturated nucleic acids (drug to base pair ratio 0.33) "melted" monophasically and with a decreased length of the cooperative unit. The obtained apparent equilibrium constants K(app) for the complexation with the discharged drug molecule showed to be a sensitive function of the ionic environment. But in contradiction to the expected release of two counterions into the solvent only a value of 1.0 was observed for the alternating copolymer poly d(AT). The complexation of berenil with poly (dA) x poly (dT) is followed by a release of 1.4 ions indicating stronger electrostatic interactions. For both polynucleotides the predicted release of two ions is not achieved. This is due to the presence of a binding mode, which involves less electrostatic interactions. From the complete data set it is proposed that the mode of binding is closely related to that found for the analogue minor groove binders DAPI and netropsin.


Assuntos
Diminazena/análogos & derivados , Poli dA-dT/química , Polidesoxirribonucleotídeos/química , Polidesoxirribonucleotídeos/metabolismo , Diminazena/química , Diminazena/metabolismo , Diminazena/farmacologia , Poli dA-dT/metabolismo , Espectrofotometria Ultravioleta , Termodinâmica
18.
Eur J Surg Oncol ; 19(1): 27-32, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8436237

RESUMO

The improvement of minimal invasive endo-urological urinary diversions in patients with malignant ureteral obstruction (MUO) provides an alternative to open surgery. Endo-urologic procedures cause less morbidity than conventional surgical techniques. From April 1986 to April 1989, 52 patients suffering from MUO representing 64 reno-ureteral units were treated by endo-urological diversions. Proper drainage was achieved in all cases. Initial retrograde JJ-stenting was successfully performed in 30 instances. Percutaneous nephrostomy tubes were primarily placed in 34 units. Fourteen of these were finally changed to a JJ-stent in eleven cases and an ileal conduit in three. Percutaneous ureteral occlusion was performed in 7 units. A positive response regarding the effect of endo-urological treatment on the patient's quality of life was obtained in 81%. Further therapies of the underlying diseases were performed in more than 30% after stabilized renal function. MUO can be treated in most cases with little morbidity and frequently without the use of external collecting devices.


Assuntos
Neoplasias do Colo/complicações , Hidronefrose/cirurgia , Derivação Urinária/métodos , Neoplasias Urogenitais/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Drenagem , Feminino , Seguimentos , Humanos , Hidronefrose/etiologia , Íleo/cirurgia , Masculino , Pessoa de Meia-Idade , Nefrostomia Percutânea , Qualidade de Vida , Estudos Retrospectivos , Taxa de Sobrevida , Derivação Urinária/efeitos adversos
19.
J Geriatr Psychiatry Neurol ; 7 Suppl 1: S12-4, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7857500

RESUMO

In a randomized, placebo-controlled, double-blind study, 39 patients with depression with somatic symptoms were treated with hypericum extract LI 160. The therapy lasted for 4 weeks; the dosage was 300 mg three times daily. At the onset of the study as well as after 2 and 4 weeks, the following criteria were analyzed: HAMD, B-L, CGI, and vegetative symptoms. The results show a significant improvement in the active treatment group at the 5% level as compared to placebo. Seventy percent of the patients treated with LI 160 were free of symptoms after 4 weeks. Typical symptoms of the depression such as lack of activity, tiredness, fatigue, and disturbed sleep, were especially responsive. In no case were any undesirable side effects observed.


Assuntos
Antidepressivos/uso terapêutico , Depressão/tratamento farmacológico , Perileno/análogos & derivados , Extratos Vegetais/uso terapêutico , Quercetina/análogos & derivados , Xantenos/uso terapêutico , Adulto , Idoso , Depressão/complicações , Método Duplo-Cego , Feminino , Humanos , Hypericum , Masculino , Pessoa de Meia-Idade , Perileno/uso terapêutico , Plantas Medicinais , Psicometria , Quercetina/uso terapêutico
20.
J Geriatr Psychiatry Neurol ; 7 Suppl 1: S24-8, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7857503

RESUMO

A randomized, double-blind study examining the effectiveness and tolerance of a standardized hypericum preparation when compared to maprotiline was performed in a group of 102 patients with depression, in accordance with ICD-10, F 32.1. The study was conducted in the offices of neurology and psychiatry specialists. The patients received, over a period of 4 weeks, either 3 x 300 mg of the hypericum extract or 3 x 25 mg maprotiline pills of identical appearance. Effectiveness was determined using the Hamilton Depression Scale (HAMD), the Depression Scale according to von Zerssen (D-S), and the Clinical Global Impression Scale (CGI). The total score of the HAMD scale dropped during the 4 weeks of therapy in both treatment groups by about 50%. The mean values of the D-S scale and the CGI scale showed similar results, and after 4 weeks of therapy, no significant differences in either treatment group were noticed. The onset of the effects occurred up to the second week of treatment, but were observed earlier with maprotiline than with the hypericum extract. On the other hand, maprotiline treatment resulted in more cases of tiredness, mouth dryness, and heart complaints.


Assuntos
Antidepressivos/uso terapêutico , Depressão/tratamento farmacológico , Maprotilina/uso terapêutico , Perileno/análogos & derivados , Extratos Vegetais/uso terapêutico , Quercetina/análogos & derivados , Xantenos/uso terapêutico , Adulto , Idoso , Antidepressivos/efeitos adversos , Depressão/diagnóstico , Método Duplo-Cego , Feminino , Humanos , Hypericum , Masculino , Maprotilina/efeitos adversos , Pessoa de Meia-Idade , Perileno/efeitos adversos , Perileno/uso terapêutico , Extratos Vegetais/efeitos adversos , Plantas Medicinais , Psicometria , Quercetina/efeitos adversos , Quercetina/uso terapêutico , Índice de Gravidade de Doença , Resultado do Tratamento , Xantenos/efeitos adversos
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