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1.
J Photochem Photobiol B ; 112: 43-7, 2012 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-22575345

RESUMO

An exact wavelength separation of the spectrum cannot be accomplished when utilizing common ultraviolet (UV) light sources, so the dependence of photodegradation on wavelength cannot be done directly. The photodegradation of wood resulted in by laser irradiation on various wavelengths can be studied by comparing the changes in the DRIFT spectra of various wood materials. The analysis of the difference spectrum is a widely used method to investigate the changes in the infrared spectrum. As this procedure cannot be used to compare the changes quantitatively, a new indicator was introduced, termed Band Damage Index (BDI). The BDI and the results obtained by its analysis are going to be discussed.


Assuntos
Lasers , Madeira/efeitos da radiação , Fagus , Fraxinus , Fotólise , Picea , Pinus sylvestris , Espectrofotometria Infravermelho
2.
Protein Sci ; 10(11): 2280-90, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11604534

RESUMO

The major serine proteinase inhibitor from bell pepper (Capsicum annuum, paprika) seeds was isolated, characterized, and sequenced, and its disulfide bond topology was determined. PSI-1.2 is a 52-amino-acid-long, cysteine-rich polypeptide that inhibits both trypsin (K(i) = 4.6 x 10(-9) M) and chymotrypsin (K(i) = 1.1 x 10(-8) M) and is a circularly permuted member of the potato type II inhibitor family. Mature proteins of this family are produced from precursor proteins containing two to eight repeat units that are proteolytically cleaved within, rather than between, the repeats. In contrast, PSI-1.2 corresponds to a complete repeat that was predicted as the putative ancestral protein of the potato type II family. To our knowledge, this is the first case in which two proteins related to each other by circular permutation are shown to exist in the same organism and are expressed within the same organ. PSI-1.2 is not derived from any of the known precursors, and it contains a unique amphiphilic segment in one of its loops. A systematic comparison of the related precursor repeat-sequences reveals common evolutionary patterns that are in agreement with the ancestral gene-duplication hypothesis.


Assuntos
Capsicum/química , Inibidores de Serina Proteinase/isolamento & purificação , Sequência de Aminoácidos , Capsicum/genética , Quimotripsina/antagonistas & inibidores , Dissulfetos/química , Evolução Molecular , Inibidores do Fator Xa , Cinética , Modelos Moleculares , Dados de Sequência Molecular , Mutação , Filogenia , Alinhamento de Sequência , Inibidores de Serina Proteinase/química , Trombina/antagonistas & inibidores , Inibidores da Tripsina/isolamento & purificação
3.
Nucleic Acids Res ; 29(1): 58-60, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11125049

RESUMO

SBASE 8.0 is the eighth release of the SBASE library of protein domain sequences that contains 294 898 annotated structural, functional, ligand-binding and topogenic segments of proteins, cross-referenced to most major sequence databases and sequence pattern collections. The entries are clustered into over 2005 statistically validated domain groups (SBASE-A) and 595 non-validated groups (SBASE-B), provided with several WWW-based search and browsing facilities for online use. A domain-search facility was developed, based on non-parametric pattern recognition methods, including artificial neural networks. SBASE 8.0 is freely available by anonymous 'ftp' file transfer from ftp.icgeb.trieste.it. Automated searching of SBASE can be carried out with the WWW servers http://www.icgeb.trieste.it/sbase/ and http://sbase.abc. hu/sbase/.


Assuntos
Bases de Dados Factuais , Proteínas , Sítios de Ligação , Serviços de Informação , Internet , Estrutura Terciária de Proteína , Proteínas/química , Alinhamento de Sequência
4.
Ann Biomed Eng ; 28(3): 331-45, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10784097

RESUMO

Facilitated transport is characteristic of most living systems, and usually involves a series of consecutive adjacent transfer regions, each having different transport properties. As a first step in the analysis of the multiregional problem, we consider in a single unstirred layer the facilitated diffusion of fatty acid (F) in albumin (A) solution under conditions of slow versus rapid association-dissociation, accounting for differing diffusivities of the albumin-fatty acid complex (AF). Diffusion gradients become established in an unstirred layer between a source of constant concentration of A, AF, and F in equilibrium, and a membrane permeable to F. The posited system does not reduce to a thin- or thick-layer approximation. The transient state is prolonged by slower on/off binding rates and by increasing the thickness of the unstirred layer. Solutions to transient and steady state depend upon the choice of boundary conditions, especially for thin regions. When there are two regions (each with its specific binding protein) separated by a permeable membrane, the steady-state fluxes and concentration profiles depend on the rates of association and dissociation reactions, on the diffusion coefficients, local consumption rates, and on the membrane permeability. Sensitivity analysis reveals the relative importance of these mechanisms.


Assuntos
Permeabilidade da Membrana Celular/fisiologia , Ácidos Graxos/sangue , Ácidos Graxos/metabolismo , Modelos Biológicos , Modelos Químicos , Ligação Proteica/fisiologia , Albumina Sérica/metabolismo , Transporte Biológico Ativo/fisiologia , Difusão , Análise Numérica Assistida por Computador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Soluções
5.
Nucleic Acids Res ; 28(1): 260-2, 2000 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-10592241

RESUMO

SBASE 7.0 is the seventh release of the SBASE protein domain library sequences that contains 237 937 annotated structural, functional, ligand-binding and topogenic segments of proteins, cross-referenced to all major sequence databases and sequence pattern collections. The entries are clustered into over 1811 groups and are provided with two WWW-based search facilities for on-line use. SBASE 7.0 is freely available by anonymous 'ftp' file transfer from ftp.icgeb. trieste.it. Automated searching of SBASE with BLAST can be carried out with the WWW servers http://www.icgeb.trieste.it/sbase/and http://sbase.abc.hu/sbase/


Assuntos
Sistemas de Gerenciamento de Base de Dados , Bases de Dados Factuais , Proteínas/química , Sequência de Aminoácidos , Internet
6.
Biosystems ; 51(2): 95-100, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10482421

RESUMO

Here we present a novel hypothesis for the origin of overlapping open reading frames (O-ORFs) observed in the 'non-coding frames' of several genes of yeast chromosome II. By computer analysis it was found that the specific amino acid content and base distribution pattern at certain genomic locations and the presence of O-ORFs were related. This observation prompt us to conclude that these O-ORFs are mere statistical curiosities without any biological function, which is in contrast to the hypotheses proposed by other authors.


Assuntos
Aminoácidos/análise , Códon , Fases de Leitura Aberta , Cromossomos Fúngicos
7.
Bioinformatics ; 15(4): 343-4, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10320404

RESUMO

RESULTS: A WWW server for protein domain homology prediction, based on BLAST search and a simple data-mining algorithm (Hegyi,H. and Pongor,S. (1993) Comput. Appl. Biosci., 9, 371-372), was constructed providing a tabulated list and a graphic plot of similarities. AVAILABILITY: http://www.icgeb.trieste.it/domain. Mirror site is available at http://sbase.abc.hu/domain. A standalone programme will be available on request. SUPPLEMENTARY INFORMATION: A series of help files is available at the above addresses.


Assuntos
Algoritmos , Conformação Proteica , Proteínas/química , Software , Humanos , Armazenamento e Recuperação da Informação
8.
Nucleic Acids Res ; 27(1): 257-9, 1999 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-9847195

RESUMO

The sixth release of the SBASE protein domain library sequences contains 130 703 annotated and crossreferenced entries corresponding to structural, functional, ligand-binding and topogenic segments of proteins. The entries were grouped based on standard names (2312 groups) and futher classified on the basis of the BLAST similarity (2463 clusters). Automated searching with BLAST and a new sequence-plot representation of local domain similarities are available at the WWW-server http://www.icgeb.trieste.it/sbase. A mirror site is at http://sbase.abc.hu/sbase. The database is freely available by anonymous 'ftp' file transfer from ftp.icgeb.trieste.it


Assuntos
Sequência de Aminoácidos , Bases de Dados Factuais , Conformação Proteica , Proteínas/química , Armazenamento e Recuperação da Informação , Internet , Proteínas/classificação , Proteínas/fisiologia , Homologia de Sequência de Aminoácidos
9.
Gene ; 188(2): 247-52, 1997 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9133599

RESUMO

Inosine-containing degenerate PCR primers corresponding to the heme-binding domain of cytochrome P450 proteins have been synthesized and used for cloning cDNAs by the RT-PCR technique from Solanum chacoense. One clone in which the primer was immediately followed by sequences corresponding to the remaining part of the conserved domain was obtained. A leaf cDNA and a genomic library were constructed from S. chacoense. Clones homologous to the PCR fragment were isolated by plaque hybridization from both libraries (CYPs.ch-1 and CYPs.ch-2, respectively). Based on DNA sequence analysis, the selected clones are 87.6% identical and belong to the CYP71 family. The CYPs.ch genes are present in multiple copies in the S. chacoense as well as in the S. tuberosum genome with some polymorphisms. The CYPs.ch transcripts are slightly induced by methyl jasmonate and abscisic acid in S. chacoense foliage.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Proteínas de Plantas/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , DNA Complementar , DNA de Plantas , Dosagem de Genes , Expressão Gênica , Genes de Plantas , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
10.
Am J Physiol ; 270(2 Pt 2): H685-91, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8779846

RESUMO

In anesthetized dogs, a 4-h, approximately 30% increase in blood pressure induced by constriction of the abdominal aorta brought about an increase in the total RNA content in the left anterior descending coronary artery (LADCA) and the left ventricular (LV) myocardium (9.05 +/- 1.72 and 11.06 +/- 4.68%, respectively) but not in the left circumflex coronary artery (LCCA). Under the same experimental conditions, [14C]leucine incorporation increased in LADCA and LV myocardium (45.34 +/- 13.54 and 58.07 +/- 11.91%, respectively), but not in LCCA. The data indicate an early shift in protein synthesis in LADCA and simultaneously in the myocardium during a short-term pressor event. The difference in the shift of protein synthesis in the two main branches of the left coronary artery was related to the quantitatively different deformation of the LADCA and LCCA due to different deformation of the underlying myocardium and/or of the annulus fibrosus atrioventricularis during changes in the left or right ventricle volume [M. Gerová, E. Barta, M. Stolárik, and J. Gero, Am. J. Physiol. 262 (Heart Circ. Physiol. 31): H1049-H1053, 1992]. The results support the hypothesis that the deformation and/or rate of deformation of cells in the coronary wall may trigger an increase in protein synthesis. Changes in protein synthesis in the myocardium and LADCA were found to be reversible 2 h after releasing the aortic constriction.


Assuntos
Vasos Coronários/metabolismo , Hipertensão/metabolismo , Proteínas Musculares/biossíntese , Animais , Artérias/metabolismo , DNA/metabolismo , Cães , Feminino , Leucina/metabolismo , Masculino , Miocárdio/metabolismo , Pericárdio , RNA/metabolismo
11.
Plant Mol Biol ; 27(3): 587-95, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7894021

RESUMO

A rich source of valuable genes are wild species. Solanum chacoense Bitter with its extreme resistance to viruses, insects and drought, is a good example. In the present study, a stress gene, designated DS2, has been isolated from S. chacoense. We have shown that the expression of the gene is organ-specific being detected in leaf, stem and stolon, but not in root, tuber or flower. Treatment of detached leaves with abscisic acid (ABA), salicylic acid or methyl jasmonate resulted in only very moderate accumulation of DS2 mRNA. Thus, DS2 represents a very rare type of the water-stress-inducible genes whose signalling pathway is not primarily related to ABA. Based on DNA sequence analysis, DS2 encodes a putative protein starting with 20 amino acids homologous to the ABA- and water-stress-inducible, ripening-related (ASR) proteins of tomato continued by an insert of 155 amino acids structurally similar to certain LEAs (late embryogenesis-abundant proteins) and ending in 88 amino acids homologous again to the ASR sequences and to an unpublished partial cDNA fragment isolated from the root of rice. The N-terminal region of the DS2 protein is hydrophilic with ten 13-mer amino acid motifs and random coil structure. In contrast, the C-terminus predicts an alpha-helix and possesses a bipartite nuclear targeting sequence motif. These data suggest that the function of the DS2 may be the protection of the nuclear DNA from desiccation.


Assuntos
Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Verduras/genética , Ácido Abscísico/farmacologia , Sequência de Aminoácidos , Aminoácidos/análise , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , Dessecação , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas/genética , Dados de Sequência Molecular , Folhas de Planta/química , Caules de Planta/química , Estrutura Secundária de Proteína , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , RNA de Plantas/análise , RNA de Plantas/biossíntese , Análise de Sequência de DNA
12.
Mol Gen Genet ; 245(4): 517-22, 1994 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-7808402

RESUMO

The patatin gene is the best known "tuber-specific" gene of potato (Solanum tuberosum). Patatin is encoded by a multigene family that can be divided into two classes. Class I genes are highly expressed in tubers and are sucrose inducible, while class II genes are under developmental control and are expressed mainly in root tips. Here we report the isolation and characterization of cDNA clones corresponding to a patatin gene of the non-tuberizing Solanum species S. brevidens. We show that the gene is 94-100% homologous to the class I type patatin genes of S. tuberosum; the homology includes the sequences in the 5' and the 3' untranslated regions. However, the patatin gene of S. brevidens is regulated like class II type patatin genes and cannot be transcriptionally activated by elevated levels of sucrose. This result further supports the idea that the components required for tuberization may be present in non-tuberizing solanaceous plants, but are regulated differently.


Assuntos
Hidrolases de Éster Carboxílico , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Proteínas de Plantas/genética , Solanum tuberosum/genética , Sequência de Aminoácidos , DNA de Plantas/genética , Dados de Sequência Molecular , Caules de Planta/genética , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Sacarose/metabolismo
13.
Bratisl Lek Listy ; 94(7): 349-53, 1993 Jul.
Artigo em Eslovaco | MEDLINE | ID: mdl-8004479

RESUMO

Levels of lactate, inorganic phosphate and uric acid in arterial, mixed venous and coronary sinus blood were studied in patients during open-heart surgery. It was found that the determination of mentioned biochemical parameters can provide information regarding the energetic metabolism status of the whole organism, but selectively, also of the patient's myocardium. The results of biochemical analyses demonstrate a significant loading of the organism manifested by metabolic alterations, especially after long-term cardiopulmonary bypass. The study of mentioned biochemical parameters can be employed for investigation of a more efficient protection of myocardium against ischemia-reperfusion injury. (Fig. 6, Ref. 18).


Assuntos
Procedimentos Cirúrgicos Cardíacos , Metabolismo Energético , Humanos , Lactatos/sangue , Fosfatos/sangue , Ácido Úrico/sangue
15.
Bratisl Lek Listy ; 94(1): 17-23, 1993 Jan.
Artigo em Eslovaco | MEDLINE | ID: mdl-8353734

RESUMO

Investigation of cardiosurgical patients have provided evidence for the generation of free oxygen radicals during open heart surgery. The finding of increased plasma malondialdehyde concentrations, considered to be an indicator of lipid peroxidation in cell membranes, is suggestive of this process. Simultaneously, the antiradical capacity of tissue was found to exhibit a decreasing trend, as established by the levels of superoxide dismutase and catalase in erythrocytes of peripheral blood which tended to diminish. The funding that no changes in the studied parameters were observed in the blood from the coronary sinus taken before and after interruption of coronary blood flow demonstrates that the commonly applied protection of the myocardium by hypothermic cardioplegic solution and topical cooling of the heart is effective in suppressing radical formation. (Fig. 5, Ref. 36.)


Assuntos
Procedimentos Cirúrgicos Cardíacos , Catalase/sangue , Radicais Livres/metabolismo , Malondialdeído/sangue , Superóxido Dismutase/sangue , Adulto , Humanos , Período Intraoperatório , Pessoa de Meia-Idade
16.
Am J Physiol ; 262(4 Pt 2): H1049-53, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1566887

RESUMO

With the use of ultrasound technique, segment length and diameter of ramus circumflexus (RC) and ramus interventricularis anterior (RIA) in the dog heart, placed in a bath, were monitored under constant pressure. When the left and/or right ventricular volume was increased by 150% of the normal diastolic filling, segment length of RC increased by 2.54 +/- 0.17 and 2.15 +/- 0.06%, respectively, and diameter of RC decreased by 4.72 +/- 0.20% and by 4.60 +/- 0.20%, respectively. The same filling of the left and/or right ventricle induced in the proximal third of RIA an increase in segment length by 11.40 +/- 0.55 and 12.2 +/- 0.42%, respectively, and a decrease in diameter by 9.41 +/- 0.42% and by 10.01 +/- 0.31%, respectively. The latter values of RIA were significantly higher (P less than 0.001) than those registered in RC. The deformations of RIA decreased toward the periphery of the vessel. By the fact that conduit coronary artery tracks instantaneously the increase of the volume of the left and right ventricle, its contribution to the total coronary resistance increases dynamically. With the ventricular volume increased by 150%, the RC contributes to the total coronary resistance by 14% and RIA in the proximal part contributes by 23%, with values significantly higher than control (10%) (Malindzak, G. S. In: The Coronary Artery. London: Croom Helm, 1982, p. 241-267). The results imply a methodical consequence, namely that the diameter of the respective coronary artery is an index of smooth muscle activity only if both perfusion pressure and volume of the heart are maintained constant.


Assuntos
Volume Sanguíneo , Circulação Coronária , Vasos Coronários/anatomia & histologia , Animais , Artérias/anatomia & histologia , Cães , Feminino , Ventrículos do Coração , Masculino , Matemática
18.
Nucleic Acids Res ; 19(18): 4983-90, 1991 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-1923766

RESUMO

We report here the isolation of the 5' end and the promoter region of the gene for chicken cartilage link protein, and demonstrate extensive heterogeneity of the leader sequence arising from differential utilization of multiple splice sites within the 5'-most exon. The 500-base pairs (bp) exon 1 consists of solely untranslated sequence and is followed by an intron greater than 33 kilobase pairs (kb). Together, the five exons predict a gene size longer than 100 kb. Multiple transcription initiation sites were mapped 34, 46, 56, 66 and 76 bp downstream of a TATA-like motif. Sequence analysis revealed that in addition to the non-spliced variant, multiple mRNA species were generated by alternative splicing resulting in the exclusion of 92, 166, 170, 174 and 263 nucleotides (nt), respectively, from exon 1. Polymerase chain reaction confirmed the existence of various splice forms, and showed cell type- and developmental stage-specific expression for one group of them. Secondary structure predictions indicated that the leaders of the splice forms could form stable hairpin structures with different free energies of formation (up to delta G = -110 kcal/mol), suggesting translational control. The splice variant detected in the largest amount had the least stable predicted hairpin (delta G = -31.7 kcal/mol).


Assuntos
Proteínas da Matriz Extracelular , Regiões Promotoras Genéticas , Sinais Direcionadores de Proteínas/genética , Proteínas/genética , Proteoglicanas , Splicing de RNA , RNA Mensageiro/genética , Animais , Sequência de Bases , Southern Blotting , Cartilagem/química , Embrião de Galinha , Éxons , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Conformação Proteica , Proteínas/química , Mapeamento por Restrição , Termodinâmica , Transcrição Gênica
19.
Bratisl Lek Listy ; 92(3-4): 174-83, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-2029659

RESUMO

The purpose of the investigation was: 1. to examine the effect of cardiopulmonary bypass (CPB) on the generation of cytotoxic oxygen-derived radicals and 2. to determine if the pretreatment of patients with vitamins E and C will combat generation of such radicals. Twenty patients undergoing CPB for treatment of cardiac disease were entered into the study and randomized to one of two groups. Group 1 (n = 9) served as control. Group 2 (n = 11) consisted of patients pretreated with 2000 IU of vitamin E 12 h prior to surgical intervention and 2 g of vitamin C given in the morning on the day of operation. Blood samples from arterial and mixed venous blood for analysis were obtained at the following intervals: 1. before anesthesia, 2. before sternotomy, 3. at the start of CPB, 4. at the end of CPB, 5. at the time of skin closure, 6. in the morning of the following day. Blood specimens from the coronary sinus were withdrawn A--before aortic cross-clamping, B--immediately after aortic declamping, C--in the 5th min, and D--in the 15th min of reperfusion. The concentration of inorganic phosphate as well as of uric acid was significantly higher in the control group what might indicate that vitamins E and C attenuate the degradation of adenine nucleotides. The most important difference between treated and control groups was observed in plasma concentration of malondialdehyde--a marker of lipid peroxidation--which was significantly lower in pretreated patients. A similar pattern of changes was found in the level of the lysosomal enzyme N-acetyl-glucosaminidase. Finally, pretreatment with vitamins E and C inhibited the decrease of catalase, observed in controls.


Assuntos
Ácido Ascórbico/uso terapêutico , Procedimentos Cirúrgicos Cardíacos , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Vitamina E/uso terapêutico , Animais , Ácido Ascórbico/administração & dosagem , Ponte Cardiopulmonar , Cricetinae , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Traumatismo por Reperfusão Miocárdica/sangue , Fosfatos/sangue , Distribuição Aleatória , Ácido Úrico/sangue , Vitamina E/administração & dosagem
20.
Bratisl Lek Listy ; 91(9): 679-88, 1990 Sep.
Artigo em Eslovaco | MEDLINE | ID: mdl-2224548

RESUMO

Perioperative myocardial infarction is a major complication of revascularization surgery of the heart which can negatively affect both the quality and duration of the patient's life. The aim of the paper is to contribute to the understanding of the problem which involves the definition, incidence, pathogenesis, diagnosis, complications, therapy and prognosis of perioperative myocardial infarction. One of the basic factors implicated in the development of perioperative derangement of the cardiac muscle is closely analyzed, namely insufficient protection of the myocardium with subsequent ischemia-reperfusion induced myocardial damage. Pitfalls of electrocardiographic diagnosis are pointed out and the rather complicated interpretation of increased enzyme levels following cardiac surgery is discussed. Complications, management, as well as early and late prognosis of patients with perioperative myocardial infarction are also dealt with.


Assuntos
Infarto do Miocárdio/etiologia , Revascularização Miocárdica/efeitos adversos , Doença das Coronárias/cirurgia , Humanos , Infarto do Miocárdio/fisiopatologia
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