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1.
J Phys Chem Lett ; 15(9): 2573-2579, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38417042

RESUMO

Surface superconductivity, wherein electron pairing occurs at material surfaces or interfaces, has attracted a remarkable amount of attention since its discovery. Recent theoretical predictions have unveiled increased critical temperatures, especially at the surfaces of certain compounds and/or structures. The notion of "surface ordering" has been advanced to elucidate this phenomenon. Employing the framework of self-consistent Bogoliubov-de Gennes equations and a model incorporating correlated disorder, our study demonstrates the persistence of the surface ordering effect in the presence of weak to moderate bulk disorder. Intriguingly, our findings indicate that under moderate disorder conditions the surface critical temperature can be further increased, depending on the intensity and correlation of the disorder.

2.
Genet. mol. res. (Online) ; 4(2): 232-250, 30 jun. 2005. ilus
Artigo em Inglês | LILACS | ID: lil-445289

RESUMO

DNA replication, together with repair mechanisms and cell cycle control, are the most important cellular processes necessary to maintain correct transfer of genetic information to the progeny. These processes are well conserved throughout the Eukarya, and the genes that are involved provide essential information for understanding the life cycle of an organism. We used computational tools for data mining of genes involved in these processes in the pathogenic fungus Paracoccidiodes brasiliensis. Data derived from transcriptome analysis revealed that the cell cycle of this fungus, as well as DNA replication and repair, and the recombination machineries, are highly similar to those of the yeast Saccharomyces cerevisiae. Among orthologs detected in both species, there are genes related to cytoskeleton structure and assembly, chromosome segregation, and cell cycle control genes. We identified at least one representative gene from each step of the initiation of DNA replication. Major players in the process of DNA damage and repair were also identified.


Assuntos
Humanos , Ciclo Celular/genética , DNA Fúngico/genética , Paracoccidioides/genética , Recombinação Genética/genética , Reparo do DNA/genética , Replicação do DNA/genética , Ciclo Celular/fisiologia , Genes Fúngicos/genética , Mutação/genética , Paracoccidioides/citologia , Recombinação Genética/fisiologia , Reparo do DNA/fisiologia , Replicação do DNA/fisiologia , Transcrição Gênica/genética
3.
Yeast ; 20(3): 263-71, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12557278

RESUMO

Paracoccidioides brasiliensis is a pathogenic fungus that undergoes a temperature-dependent cell morphology change from mycelium (22 degrees C) to yeast (36 degrees C). It is assumed that this morphological transition correlates with the infection of the human host. Our goal was to identify genes expressed in the mycelium (M) and yeast (Y) forms by EST sequencing in order to generate a partial map of the fungus transcriptome. Individual EST sequences were clustered by the CAP3 program and annotated using Blastx similarity analysis and InterPro Scan. Three different databases, GenBank nr, COG (clusters of orthologous groups) and GO (gene ontology) were used for annotation. A total of 3,938 (Y = 1,654 and M = 2,274) ESTs were sequenced and clustered into 597 contigs and 1,563 singlets, making up a total of 2,160 genes, which possibly represent one-quarter of the complete gene repertoire in P. brasiliensis. From this total, 1,040 were successfully annotated and 894 could be classified in 18 functional COG categories as follows: cellular metabolism (44%); information storage and processing (25%); cellular processes-cell division, posttranslational modifications, among others (19%); and genes of unknown functions (12%). Computer analysis enabled us to identify some genes potentially involved in the dimorphic transition and drug resistance. Furthermore, computer subtraction analysis revealed several genes possibly expressed in stage-specific forms of P. brasiliensis. Further analysis of these genes may provide new insights into the pathology and differentiation of P. brasiliensis.


Assuntos
Etiquetas de Sequências Expressas , Genoma Fúngico , Paracoccidioides/genética , Sequência de Bases , Brasil , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Transcrição Gênica
4.
Aesthetic Plast Surg ; 25(6): 447-53, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11731852

RESUMO

Endolaser mid-face lift was performed on patients in a multi-center study over a 36-month period (Feb. 1998 to Feb. 2001). It permits significant facial rejuvenation through small incisions. This technique achieves aesthetic results and wider rejuvenation while being less traumatic and creating minimal morbidity. Combined with other procedures, it rejuvenates the face by three strategic methods: soft tissue suspension, reversal of photo aging, and correction of the depletion of volume. To achieve this triple result, the mid-face lift is performed by endoscopic approach, and in every case is combined with the endoscopic lift of the frontal area. Laser resurfacing was used to reverse skin photo damage. The Ultrapulse CO2 laser and/or the Ultrafine Erbium YAG(Coherent, Inc, Palo Alto, CA) were used. The third combined procedure was the introduction of fat graft to compensate the atrophy/ptosis of fat and the depletion of bone mass (other filling materials besides fat may be used, depending on the preference of the surgeon). Our method of fixation using the Casagrande Needle (an evolution of Reverdin Needle) makes the mechanical purchase on the tissues to be suspended much easier, permitting the intra-oral and/or infra-orbital incisions to be eliminated. The present study of the technical evolution of the endolaser mid-face lift method allows us to conclude that a very satisfactory outcome has been reached, offering patients a minimally invasive procedure, which can be performed under local anesthesia, with low morbidity, imperceptible incisions, and an excellent long-term result.


Assuntos
Endoscopia , Terapia a Laser , Ritidoplastia/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Envelhecimento da Pele
5.
J Biochem ; 128(6): 891-5, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11098129

RESUMO

We report two expression vectors in Pichia pastoris that direct the synthesis of recombinant single chain antibody variable region (scFv), derived from anti-Z-DNA monoclonal antibody Z22. The first vector codes for a scFv fused to the Ig binding domain of staphylococcal Protein A. The second vector codes for the scFv fused to the Fc fragment of the human IgG1. The fusion partner simplified the detection and purification of the secreted protein. These constructs yielded high level expression of an scFv with specific binding activity toward a Z form of DNA, with binding activity comparable to that of the scFv molecule produced in an Escherichia coli expression system and the original monoclonal antibody.


Assuntos
Antígenos/imunologia , Imunoglobulina G/genética , Região Variável de Imunoglobulina/genética , Pichia/genética , Sequência de Bases , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Vetores Genéticos , Humanos , Região Variável de Imunoglobulina/imunologia , Oligodesoxirribonucleotídeos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/isolamento & purificação
6.
FEMS Microbiol Lett ; 169(1): 185-90, 1998 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9851051

RESUMO

Germinated conidia of the thermophilic fungus Humicola grisea var. thermoidea were transformed to hygromycin B resistance using the plasmid pAN7.1. Transformation was achieved using lithium acetate treatment or electroporation. The efficiency of transformation was up to 32 and 25 transformants per microgram of plasmid DNA with the two methods, respectively. Transformants obtained by the lithium acetate method were more stable and showed a high copy number of the hph gene integrated into their genome. The other transformants, from the electroporation procedure, were stable, but unable to grow in the presence of high levels of hygromycin, and detection of the hph gene was only possible by polymerase chain reaction analysis.


Assuntos
Higromicina B/farmacologia , Fungos Mitospóricos/genética , Transformação Genética , Relação Dose-Resposta a Droga , Resistência Microbiana a Medicamentos , Eletroporação , Temperatura Alta , Compostos de Lítio , Mitose , Fungos Mitospóricos/crescimento & desenvolvimento , Esporos Fúngicos/genética , Esporos Fúngicos/crescimento & desenvolvimento
7.
Appl Microbiol Biotechnol ; 43(6): 1067-76, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8590658

RESUMO

Eight constructions involving the Bacillus subtilis alpha-amylase gene (amyE), a mouse pancreatic alpha-amylase cDNA (AMY2) and an Aspergillus awamori glucoamylase cDNA (glaA) were prepared: three fusion genes, involving one alpha-amylase and the glucoamylase, two double-cassette plasmids (expressing one or other alpha-amylase and the glucoamylase) and three single-cassette plasmids, expressing the individual coding sequences. Following transformation of each plasmid into Saccharomyces cerevisiae, a plate test revealed that the largest starch hydrolysis halo was produced by the strain bearing the B. subtilis alpha-amylase/glucoamylase fusion (BsAAase/GAase), and the smallest halo by the one expressing the mouse pancreatic alpha-amylase/glucoamylase fusion (MAAase/GAase). When assayed for enzymatic activity in liquid medium, the strains bearing the fusion and the double-cassette plasmids involving B. subtilis alpha-amylase and the glucoamylase exhibited both enzymic activities. Moreover, the BsAAase/GAase hybrid was able to adsorb and digest raw starch. The MAAse/GAase fusion protein was found to exhibit only alpha-amylase activity. Finally, the capacity to grow on soluble and corn starch was tested in liquid medium for the strains bearing plasmids coding for the fusion proteins and the separate enzymes. The strain carrying the double-cassette BsAAase + GAase, which produced one of the smallest hydrolysis haloes in the place test, showed the best performance, not only in digesting soluble and corn starch but also in using all of the hydrolysis products for growth. The transformant bearing the BsAAase/GAase fusion was able to grow on soluble starch, but not on corn starch.


Assuntos
Glucana 1,4-alfa-Glucosidase/biossíntese , Proteínas Recombinantes de Fusão/biossíntese , Saccharomyces cerevisiae/metabolismo , Amido/metabolismo , alfa-Amilases/biossíntese , Animais , Aspergillus/enzimologia , Aspergillus/genética , Bacillus subtilis/enzimologia , Bacillus subtilis/genética , Proteínas de Bactérias/genética , Cromatografia de Afinidade , Indução Enzimática , Escherichia coli/metabolismo , Proteínas Fúngicas/biossíntese , Proteínas Fúngicas/genética , Proteínas Fúngicas/isolamento & purificação , Regulação Fúngica da Expressão Gênica , Vetores Genéticos/genética , Glucana 1,4-alfa-Glucosidase/genética , Glucana 1,4-alfa-Glucosidase/isolamento & purificação , Hidrólise , Camundongos/genética , Pâncreas/enzimologia , Especificidade por Substrato , alfa-Amilases/genética , alfa-Amilases/isolamento & purificação
8.
Int Surg ; 74(2): 107-8, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2787789

RESUMO

A case of gastroatrial fistula following resection of a carcinoma of the mid-esophagus and re-establishment of the alimentary tract with a cervical esophagogastrostomy is presented. Three episodes of moderate upper gastrointestinal hemorrhage secondary to chronic peptic ulcer of the stomach placed in the thorax occurred three years after the operation. At this time, the patient was also admitted to the hospital with diagnosis of pericarditis of unknown etiology. Three years later the patient had a massive and fatal episode of upper gastrointestinal bleeding.


Assuntos
Esôfago/cirurgia , Fístula/etiologia , Fístula Gástrica/etiologia , Cardiopatias/etiologia , Complicações Pós-Operatórias , Estômago/cirurgia , Adulto , Neoplasias Esofágicas/cirurgia , Hemorragia Gastrointestinal/etiologia , Humanos , Masculino , Úlcera Péptica/etiologia
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