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1.
Rev Alerg Mex ; 56(2): 36-40, 2009.
Artigo em Espanhol | MEDLINE | ID: mdl-19526952

RESUMO

BACKGROUND: Allergic rhinitis is an inflammatory disease of the nasal mucosa, with common symptoms, which is essentially characterized by nasal itching, nasal congestion, sneezing, hyaline rhinorrhea and repetitive sneezing. The disease is very common, 15% of the population worldwide suffers it. Among many treatments that have been used to relieve the symptoms of this disease there is a selective inhibitor of H1 receptors, ebastine. OBJECTIVE: To evaluate patient satisfaction using the scale of Treatment Satisfaction Questionnaire for Medication (TSQM). MATERIAL AND METHODS: A multicentric, retrospective, observational study performed in 250 Mexican patients with the diagnosis of intermittent allergic rhinitis (IAR) or persistent allergic rhinitis (PER), confirmed by prick test, specific IgE, or both, treated with lyophilised ebastine in fast-dissolving (FDT) 20 mg at any time in the last two months, prescribed for at least two weeks by their doctor to relieve the symptoms of intermittent allergic rhinitis or persistent allergic rhinitis. We used a validated questionnaire assessment scales, TSQM. RESULTS: The presentation of ebastine fast-dissolving (FDT) is effective and has good tolerability, over 80% of patients reported comfort and satisfaction using it. CONCLUSIONS: Assessment of overall satisfaction, efficacy, tolerability and comfort showed that ebastine in fast-dissolving is an antihistamine with clear benefits to encourage compliance.


Assuntos
Butirofenonas/administração & dosagem , Antagonistas dos Receptores Histamínicos H1/administração & dosagem , Piperidinas/administração & dosagem , Rinite Alérgica Perene/tratamento farmacológico , Rinite Alérgica Sazonal/tratamento farmacológico , Adolescente , Adulto , Butirofenonas/uso terapêutico , Feminino , Humanos , Masculino , México , Pessoa de Meia-Idade , Satisfação do Paciente , Piperidinas/uso terapêutico , Estudos Retrospectivos , Solubilidade , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
2.
Biochemistry ; 40(3): 657-64, 2001 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-11170382

RESUMO

This investigation ascertains whether, in (smooth muscle) myosin, certain residues engage in functional interactions with their actin conjugates in an actomyosin complex. Such interactions have been postulated from putting together crystallographic models of the two proteins [Rayment, I., Rypniewski, W. R., Schmidt-Bäse, K., Smith, R., Tomchick, D. R., Benning, M. M., Winkelmann, D. A., Wesenberg, G., and Holden, H. M. (1993) Science 261, 50-58]. Here, in several instances, we ask whether mutation of a particular residue significantly impairs a function, and find that the answers are largely rationalized by the original postulation. Additionally, a novel element emerges from our investigation. To assess function, we test the wild type and mutant systems as they perform in the steady state of ATP degradation. In doing so, we assume, as usual, that degradation proceeds from an early stage in which the complex forms (and is described by parameter K(app)) to a later stage during which the product leaves the complex (and is described by parameter V(max)). Interestingly, certain defects induced by the mutations are associated with changes in K(app), and other defects are associated with changes in V(max), suggesting that our procedure at least roughly distinguishes between events according to the time in the degradation at which they occur. In this framework, we suggest that (1) in the actin-myosin association phase, cationic residues Lys-576 and Lys-578 interact with anionic residues of the so-called second actin, and (2) in the product leaving phase, hydrophobic residues Trp-546, Phe-547, and Pro-548, as well as the Thr-532/Asn-533/Pro-534/Pro-535 sequence, sever connections with the so-called first actin. The role of Glu-473 is also examined.


Assuntos
Actinas/fisiologia , Miosinas/química , Miosinas/fisiologia , Actinas/química , Actinas/metabolismo , Actinas/ultraestrutura , Animais , Bovinos , Ativação Enzimática/genética , Substâncias Macromoleculares , Músculo Liso/química , Músculo Liso/metabolismo , Músculo Liso/fisiologia , Mutagênese Sítio-Dirigida , Subfragmentos de Miosina/genética , Subfragmentos de Miosina/isolamento & purificação , Subfragmentos de Miosina/metabolismo , Subfragmentos de Miosina/ultraestrutura , Miosinas/genética , Miosinas/metabolismo , Miosinas/ultraestrutura , Estrutura Secundária de Proteína , Coelhos , Propriedades de Superfície
3.
Proc Natl Acad Sci U S A ; 97(21): 11203-8, 2000 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-11016961

RESUMO

Initially, we asked which (of 10) smooth muscle myosin head residues responds to MgADP or MgATP binding with enhanced fluorescence emission (Trp-441 and Trp-512 were leading candidates)? To decide, we prepared sham-mutated smooth muscle heavy meromyosin (HMM), W441F HMM, and W512F HMM. On adding MgATP, emission of wild-type and W441F HMMs increased by 25-27%, but that of W512F HMM by 5%. So, in myosin, 512 is the "sensitive Trp." Unexpectedly, properties of W512F HMM [elevated Ca(2+)-ATPase, depressed EDTA (K(+))-ATPase, no regulation of its basal or actin-activated Mg(2+)-ATPase by phosphorylation of its "regulatory" light chain, limited actin activation, and inability to move actin filaments in a motility assay] are strikingly like those of smooth muscle myosin reacted at Cys-717 with thiol reagent. From crystallography-based [Houdusse, A., Kalabakis, V. N., Himmel, D., Szent-Györgyi, A. G. & Cohen, C. (1999) Cell 97, 459-470] simulations, we found that in wild-type HMM with MgADP added, Trp-512 is in a "hydrophobic pocket," but that pocket becomes distorted in W512F HMM. We think that there is a "path of influence" from 512 to 717 to the active site. We suggest that the mutational changes at 512 are transmitted along this path to Cys-717, where they induce changes similar to those caused by reacting wild-type HMM with thiol reagent.


Assuntos
Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Músculo Liso/metabolismo , Miosinas/metabolismo , Triptofano/metabolismo , Animais , Sequência de Bases , Sítios de Ligação , Primers do DNA , Mutagênese , Miosinas/química , Miosinas/genética , Coelhos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Espectrometria de Fluorescência
4.
Proc Natl Acad Sci U S A ; 95(12): 6653-8, 1998 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-9618467

RESUMO

For analyzing the mechanism of energy transduction in the "motor" protein, myosin, it is opportune both to model the structural change in the hydrolytic transition, ATP (myosin-bound) + H2O --> ADP.Pi (myosin-bound) and to check the plausibility of the model by appropriate site-directed mutations in the functional system. Here, we made a series of mutations to investigate the role of the salt-bridge between Glu-470 and Arg-247 (of chicken smooth muscle myosin) that has been inferred from crystallography to be a central feature of the transition [Fisher, A. J., Smith, C. A., Thoden, J. B. , Smith, R., Sutoh, K., Holden, H. M., & Rayment, I. (1995) Biochemistry 34, 8960-8972]. Our results suggest that whether in the normal, or in the inverted, direction an intact salt-bridge is necessary for ATP hydrolysis, but when the salt-bridge is in the inverted direction it does not support actin activation. Normally, fluorescence changes result from adding nucleotides to myosin; these signals are reported by Trp-512 (of chicken smooth muscle myosin). Our results also suggest that structural impairments in the 470-247 region interfere with the transmission of these signals to the responsive Trp.


Assuntos
Subfragmentos de Miosina/química , Conformação Proteica , Triptofano/química , Animais , Galinhas , Mutagênese Sítio-Dirigida , Subfragmentos de Miosina/genética , Subfragmentos de Miosina/metabolismo , Mutação Puntual , Sais , Relação Estrutura-Atividade , Triptofano/metabolismo
5.
Methods Enzymol ; 183: 306-17, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-1690336

RESUMO

The current version of RNAFOLD now has the capability for conducting comparative studies relative to nonbifurcating hairpins contained in the global structures produced by the dynamic programming and Monte Carlo methods. It also has the capability of both finding and comparing hairpins and pseudoknots independently of global structures. The efficacy of these increased capabilities has been tested for select families of sequences, and the results thus far indicate favorable utility. Under consideration is a further extension designed to incorporate pseudoknots within global structures. Written in the C language, RNAFOLD and its companion program, GENALIGN, for doing multiple alignments in the comparison of pseudoknots and hairpins, is available for UNIX systems on standard 1/2-inch, 9-track tape or on SUN tape cartridges.


Assuntos
Sequência de Bases , Conformação de Ácido Nucleico , RNA , Software , Dados de Sequência Molecular , Método de Monte Carlo
6.
Nucleic Acids Res ; 16(5): 1789-98, 1988 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-2451219

RESUMO

A multiple approach to the study of RNA secondary structure is described which provides for the independent drawing of structures using base-pairing lists, for the generation of local structures in the form of hairpins, and for the generation of global structures by both Monte Carlo and dynamic programming methodologies. User-adjustable parameters provide for limiting the size of hairpin loops, bulges and inner loops, and constraints can be imposed relative to position-dependent base pairing.


Assuntos
Conformação de Ácido Nucleico , RNA , Software/métodos , Algoritmos , Animais , Sequência de Bases , Galinhas , Gráficos por Computador , Dados de Sequência Molecular , Oncogenes , Linguagens de Programação
7.
Nucleic Acids Res ; 16(5): 1683-91, 1988 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-3127810

RESUMO

The 'regions' method for multisequence alignment used in the previously reported program MALIGN has been generalized to include recursive refinement so that unaligned portions between two regions at the current level of resolution can be handled with increased resolution. Additionally, there is incorporated a limiting of the number of regions to be used at any level of resolution from which to abstract an alignment. This provides a significant increase in speed over the unlimited version. The program GENALIGN uses this improved regions method to execute fast pairwise alignments in the framework of Taylor's multisequence alignment procedure using clustered pairwise alignments. Pairwise alignments by dynamic programming are also provided in the program.


Assuntos
Sequência de Aminoácidos , Sequência de Bases , Homologia de Sequência do Ácido Nucleico , Software/métodos , Timidilato Sintase , Algoritmos , Escherichia coli/enzimologia , Humanos , Lacticaseibacillus casei/enzimologia , Microcomputadores , Dados de Sequência Molecular , Fagos T/enzimologia
9.
Nucleic Acids Res ; 14(1): 363-74, 1986 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-3753772

RESUMO

A program is described for simultaneously aligning two or more molecular sequences which is based on first finding common segments above a specified length and then piecing these together to maximize an alignment scoring function. Optimal as well as near-optimal alignments are found, and there is also provided a means for randomizing the given sequences for testing the statistical significance of an alignment. Alignments may be made in the original alphabets of the sequences or in user-specified alternate ones to take advantage of chemical similarities (such as hydrophobic-hydrophilic).


Assuntos
Sequência de Aminoácidos , Sequência de Bases , Computadores , Software , Sequências Repetitivas de Ácido Nucleico
10.
EMBO J ; 3(9): 2041-6, 1984 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6092053

RESUMO

We have determined the complete sequence of the gamma 3 heavy chain constant (C gamma 3) region gene of the BALB/c mouse including the 5'-flanking region up to the switch site and the 3'-flanking region past the end of the membrane exons. The C gamma 3 coding region, typical of other IgGs, is divided into six exons corresponding to the protein domains (C gamma (3)1, hinge, C gamma (3)2, and C gamma (3)3) and to the membrane carboxyl terminus (M1 and M2). The predicted amino acid sequence of the gamma 3 chain has three potential N-linked carbohydrate addition sites (including one in the membrane spacer segment), as compared with a single occurrence in the other mouse IgGs. Between the switch recombination region and the body of the C gamma 3 gene, there is a remarkable homology with a sequence between C mu and C delta which provides a rationale for an alternative, T cell-independent class-switch mechanism. We have used a computer to analyze the secondary structure of the gamma 3 mRNA precursor for the membrane form. We predict that this RNA precursor (approximately 12 000 bp) folds into four leaf-like domains which correspond to the variable region, the large IVS, the body of the constant region, and the membrane exons. This organization may have a role to play in the function of the mRNA precursor.


Assuntos
Genes , Regiões Constantes de Imunoglobulina/genética , Imunoglobulina G/genética , Imunoglobulinas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Enzimas de Restrição do DNA , Camundongos , Camundongos Endogâmicos BALB C , Conformação de Ácido Nucleico , RNA Mensageiro/genética
11.
Nucleic Acids Res ; 12(1 Pt 1): 323-34, 1984 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-6198621

RESUMO

The folding of single-stranded RNA into its secondary structure is postulated to be equivalent to the simple rule that the next double-helical region (stem) to form is the one with the largest equilibrium constant. The rule is tested and shown to give results consistent with the enzyme cleavage data of several sequences. Computational time complexity is of order NxN for a sequence of N bases. A modification of the rule provides for the probabilistic choice of the next stem among those having an equilibrium constant within a specified range of the largest. Populations of competing structures are thus generated for detecting common characteristics and for assessing the applicability of the simple rule.


Assuntos
RNA , Ligação de Hidrogênio , Conformação de Ácido Nucleico , Precursores de Ácido Nucleico , RNA Ribossômico , RNA de Transferência , Termodinâmica
12.
Nucleic Acids Res ; 11(13): 4629-34, 1983 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-6866775

RESUMO

The problem of finding repeats in molecular sequences is approached as a sorting problem. It leads to a method which is linear in space complexity and NlogN in expected time complexity. The implementation is straightforward and can therefore be used to handle large sequences with relative ease. Of particular interest is that several sequences can be treated as a single sequence. This leads to an efficient method for finding dyads and for finding common features of many sequences, such as favorable alignments.


Assuntos
Sequências Repetitivas de Ácido Nucleico , Computadores , Métodos
13.
Ann Neurol ; 11(4): 353-8, 1982 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6808890

RESUMO

The titer of the scrapie agent was determined by measurements of time intervals from inoculation to onset of illness and from inoculation to death. Both intervals were found to be inversely proportional to the size of the dose injected intracerebrally into random-bred weanling Syrian hamsters. The logarithms of the time intervals minus a time factor were linear functions of the logarithm of the inoculum size. The time factors were determined by regression analysis in order to maximize these linear relationships. An equation relating the titer of the inoculum to the dilution of the sample and the length of the time intervals was developed. This equation facilitates the use of a computerized data base. Validation of these relationships was provided by comparing samples for which the agent was measured both by end-point titration and by time interval assay. Agreement between the two methods was generally within +/-0.5 log10 median infective dose units. No differences between the molecular properties of the agents from hamster and murine sources were observed using primarily the incubation time interval method with the former and end-point titration with the latter. The advantages of this new approach based on time interval measurements are considerable with respect to time and resources.


Assuntos
Príons/isolamento & purificação , Scrapie/microbiologia , Animais , Cricetinae , Cinética , Mesocricetus , Ovinos , Replicação Viral
14.
Biochemistry ; 19(21): 4883-91, 1980 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-6775697

RESUMO

The scrapie agent causes a progressive degeneration of the central nervous system of animals after a prolonged incubation period. Measurements of incubation period length, defined as the time from inoculation to the onset of clinical signs of neurological dysfunction, were related to the titer of the agent and the dilution of the inoculated sample. Equations defining the relationship provide a new assay for the agent requiring fewer animals than end point titrations. By use of this incubation period assay, the scrapie agent from hamster brain was found to have an s20,w of < 300 S but > 30 S assuming rho p = 1.2 g/cm3. A partially purified fraction P3 was obtained by differential centrifugation and sodium deoxycholate extraction. When P3 was extracted with phenol, virtually no infectivity was found in the aqueous phase even after examining such variables as pH, salt concentration, and predigestion of samples with proteinase K. Nonionic and nondenaturing, anionic detergents did not inactivate the scrapie agent; in contrast, denaturing detergents inactivated the agent. Sodium dodecyl sulfate (NaDodSO4) inactivated greater than 90% of the agent at a NaDodSO4 to protein ratio of 1.8 g/g. Inactivation by NaDodSO4 appears to be a cooperative process. Addition of a nonionic detergent to form mixed micelles with NaDodSO4 prevented inactivation of the agent by NaDodSO4. Weak chaotropic ions do not inactivate the scrapie agent while strong chaotropic ions like SCN- and Cl3CCOO- destroy infectivity at concentrations of 0.2 M. These data provide evidence in support of a protein component within the scrapie agent which is essential for maintenance of infectivity. Thus, it is unlikely that the scrapie agent is composed only of a "naked" nucleic acid as is the case for the plant viroids.


Assuntos
Príons/isolamento & purificação , Scrapie/microbiologia , Animais , Encéfalo/microbiologia , Centrifugação , Cricetinae , Detergentes/farmacologia , Feminino , Mesocricetus , Métodos , Príons/efeitos dos fármacos , Ovinos
15.
Biosystems ; 11(2-3): 133-62, 1979 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-497365

RESUMO

There is presented in outline form an abstract model of a cell in an evolutionary context. The design is based on an elaboration of John Holland's one-dimensional, abstract universe recently posed for the study of the emergence of self-replicating systems. Eight new ingredients constitute the elaboration. They suggest how compartmentation of a set of "molecules" in a one-dimensional universe can be achieved and how a suitable, compartmentalized set of molecules can replicate in a manner analogous to real cell replication, i.e., there is segregation and semi-conservative replication of the genetic material, and there is division of the compartment through the construction of an "inner membrane". The approach to self-replication of a spatially delimited entity exemplified by this design differs from the abstract models of replication of the von Neumann or Laing type. In these the replicating entity constructs a copy external to itself and does not undergo any essential replacement of any of its parts. Also, while in these models the concern is primarily with questions of the "logical" type, our design has in mind features identifiable with both energy and information considerations. Thus, the rules which define the underlying "physics and chemistry" imply that the self-replicating entity is a dissipative structure. A constant flux of energy is required to maintain the system far from thermodynamic equilibrium in order to account for multiple steady states, and hence dynamic structure.


Assuntos
Divisão Celular , Fenômenos Fisiológicos Celulares , Computadores , Modelos Biológicos , Compartimento Celular , Genes , Matemática , Termodinâmica
16.
Science ; 198(4312): 56-8, 1977 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-197603

RESUMO

A highly synchronized ultradian cortisol rhythm with a predominant periodicity of 85 to 90 minutes was observed in eight isolated monkeys; this rhythm may be harmonically related to the circadian rhythm. The persistence of this synchronized rhythm during supramaximal infusions of adrenocorticotropin not only suggests that feedback is not causative but also challenges the classic concept that bursts of cortisol secretion are dependent upon an immediately preceding release of adrenocorticotropin.


Assuntos
Hidrocortisona/sangue , Periodicidade , Hormônio Adrenocorticotrópico/farmacologia , Animais , Ritmo Circadiano , Retroalimentação , Haplorrinos , Macaca mulatta , Masculino
17.
J Biol Chem ; 251(2): 334-43, 1976 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-173716

RESUMO

The binding of the "activated" receptor-glucocorticoid complexes of cultured rat hepatoma cells to nuclei, chromatin, and DNA has been studied under cell-free conditions. A critical factor in determining the shape of the binding curve is shown to be an inhibitory material which is present in crude cytosol and which can be removed without destroying the receptor-steroid complex. These and other results argue that the apparent saturation observed in earlier experiments may have been due to the inhibitors. Thus, the actual number of acceptor sites in hepatoma tissue culture cell nuclei is much larger than previously estimated and their affinity for the complex is lower. Nuclear binding experiments indicate that the inhibitory material interacts with the receptor-steroid complex. The inhibitors appear to be macromolecular; but their effects cannot be mimicked by albumin or hemoglobin. The acceptor capacity at low ionic strength for binding receptor-glucocorticoid complexes increases when proceeding from nuclei to DNA. An analysis of the kinetics of association and dissociation and of the relative binding behavior of nuclei and DNA argues that the affinity of complex for nuclei is much greater than for DNA. DNA-associated histones reduce the amount of complex that binds to DNA. These and perhaps other chromosomal proteins may be responsible for the ordering of acceptor capacity. Evidence is presented that the difference in affinities of nuclear and DNA acceptors could also be due to chromosomal proteins. In nuclei, these proteins may thus both reduce the amount of complex binding by rendering regions of DNA less accessible and increase the binding affinity of some, or all, of those DNA binding sites which remain exposed.


Assuntos
Glucocorticoides/metabolismo , Proteínas de Neoplasias/metabolismo , Receptores de Superfície Celular , Esteroides/metabolismo , Sítios de Ligação , Linhagem Celular , Núcleo Celular/metabolismo , Cromatina/metabolismo , Computadores , Citosol/metabolismo , DNA de Neoplasias/metabolismo , Cinética , Matemática , Modelos Biológicos , Ligação Proteica
18.
J Cell Physiol ; 86(3 Pt 1): 511-21, 1975 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1202031

RESUMO

To investigate whether the metabolism of the polyamines putrescine, spermidine and spermine is related to cellular growth rate, we have measured the activities of L-ornithine decarboxylase and S-adenosyl-L-methionine decarboxylase as well as the levels of the polyamines in rat brain tumor cells at various stages of a 7-day in vitro growth period and correlated them with the continuous changes in specific growth rate ([dN[t]/dt]/N[t]). L-Ornithine decarboxylase and S-adenosyl-L-methionine decarboxylase both exhibited their maximal activities at the time of most rapid growth. A high positive correlation between the activities of these enzymes and the specific growth rate of the tumor cells during the entire growth period was demonstrated statistically. The pattern of fluctuation of the spermidine content during the culture cycle was similar to those of the enzyme activities and likewise showed a high positive correlation with the specific growth rate of the tumor cells during the entire growth period. The putrescine content exhibited a low positive correlation, whereas the spermine content exhibited a somewhat higher, but negative correlation with the specific growth rate. The high correlation between the specific growth rate of the tumor cells and the synthesis of the polyamines indicates that these events are primarily associated with processes involved in cell replication. Putrescine and spermidine are thought to participate in the regulation of cellular growth rate; a high content may augment, and a low content may restrain, cellular growth rate.


Assuntos
Divisão Celular , Putrescina/biossíntese , Espermidina/biossíntese , Espermina/biossíntese , Adenosilmetionina Descarboxilase/metabolismo , Linhagem Celular , Ornitina Descarboxilase/metabolismo
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