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1.
Gene Ther ; 24(9): 578-580, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28753203

RESUMEN

Latin America (LA) has a population of ~645 million people distributed over 33 countries with marked political, cultural and economic differences. In LA, patients with inherited neuromuscular diseases (NMDs) often do not have access to specialized medical centers and many of them go undiagnosed. General management and care of spinal muscular dystrophy (SMA) patients in the region varies due to heterogeneous health care. An active generation of young clinical neurologists is being trained for the specialized care of SMA and other neuromuscular (NM) patients, both in the private and public sectors. The Euro-Latin-American Summer School of Myology (EVELAM) as well as efforts of professionals at large public centers in the major cities of LA have a leading role in this development. Different regional academic-scientific organizations as well as the expanding number of telethon centers and the creation of parent organizations, mostly concerning SMA, all together are contributing to the increased quality of the management of NMD patients. Over the past years, academic and clinical research, as well as the establishment of qualified centers for the molecular testing of NMD are pushing forward the creation of patient registries and the development of specific clinical trials, with Argentina and Brazil having a major role in this field. Nevertheless, increased awareness and further training of specialized health professionals are necessary to reach patients that are currently lacking care throughout the region.


Asunto(s)
Manejo de la Enfermedad , Atrofia Muscular Espinal/terapia , Sistema de Registros , Ensayos Clínicos como Asunto , Humanos , América Latina , Atrofia Muscular Espinal/epidemiología , Participación del Paciente
2.
Int Endod J ; 50(8): 771-779, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27521570

RESUMEN

AIM: To evaluate the effect of a calcium aluminate-based cement (CAC+) on the development of the osteogenic phenotype in vitro. METHODOLOGY: Rat calvaria-derived cells were grown on Thermanox® coverslips for 24 h and then exposed to either samples (4-h set) of CAC+ or mineral trioxide aggregate (MTA) placed on Transwell® inserts for periods of up to 14 days. Nonexposed cultures were used as the controls. The comparisons were made using the nonparametric Kruskal-Wallis test, followed by the Student-Newman-Keuls post hoc test when appropriate. RESULTS: The results showed that proximity to MTA or CAC+ samples inhibited cell growth, whereas at a distance, viable and proliferative cells adhered to and spread on the Thermanox® , expressing osteoblast differentiation markers prior to mineralization of the extracellular matrix. Compared with MTA, the osteogenic cell cultures exposed to CAC+ exhibited significantly greater cell viability, alkaline phosphatase (ALP) activity and expression of runt-related transcription factor 2, osterix, ALP, bone sialoprotein and osteocalcin (P < 0.05 for all). For the osteogenic cell cultures exposed to CAC+, the quantification of matrix mineralization was not altered (P > 0.05). CONCLUSIONS: CAC+ supported the acquisition of the osteogenic cell phenotype in vitro, rendering this novel material a potential alternative to MTA in endodontic procedures. Further in vivo studies are needed to verify if the beneficial in vitro effects of CAC+ on osteoblastic cells correspond to an increase and/or acceleration of bone repair in the periapical region.


Asunto(s)
Compuestos de Aluminio/farmacología , Compuestos de Calcio/farmacología , Cementos Dentales/farmacología , Osteogénesis/efectos de los fármacos , Animales , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Combinación de Medicamentos , Osteoblastos/efectos de los fármacos , Óxidos/farmacología , Ratas Wistar , Silicatos/farmacología
3.
J Cell Biochem ; 115(3): 540-8, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24122940

RESUMEN

The aim of our study was to investigate the osteoinductive potential of a titanium (Ti) surface with nanotopography, using mesenchymal stem cells (MSCs) and the mechanism involved in this phenomenon. Polished Ti discs were chemically treated with H2 SO4 /H2 O2 to yield nanotopography and rat MSCs were cultured under osteogenic and non-osteogenic conditions on both nanotopography and untreated polished (control) Ti surfaces. The nanotopography increased cell proliferation and alkaline phosphatase (Alp) activity and upregulated the gene expression of key bone markers of cells grown under both osteogenic and non-osteogenic conditions. Additionally, the gene expression of α1 and ß1 integrins was higher in cells grown on Ti with nanotopography under non-osteogeneic condition compared with control Ti surface. The higher gene expression of bone markers and Alp activity induced by Ti with nanotopography was reduced by obtustatin, an α1ß1 integrin inhibitor. These results indicate that α1ß1 integrin signaling pathway determines the osteoinductive effect of nanotopography on MSCs. This finding highlights a novel mechanism involved in nanosurface-mediated MSCs fate and may contribute to the development of new surface modifications aiming to accelerate and/or enhance the process of osseointegration.


Asunto(s)
Integrina alfa1beta1/genética , Células Madre Mesenquimatosas/citología , Nanotecnología , Osteoblastos/citología , Titanio/química , Animales , Adhesión Celular/genética , Diferenciación Celular/genética , Proliferación Celular/efectos de los fármacos , Integrina alfa1beta1/metabolismo , Células Madre Mesenquimatosas/metabolismo , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Osteogénesis/genética , Ratas , Transducción de Señal/efectos de los fármacos , Propiedades de Superficie , Venenos de Víboras/farmacología
4.
J Chem Phys ; 141(18): 184308, 2014 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-25399148

RESUMEN

Phthalocyanine molecules have been adsorbed to Ir(111) and to graphene on Ir(111). From a comparison of scanning tunneling microscopy images of individual molecules adsorbed to the different surfaces alone it is difficult to discern potential differences in the molecular adsorption geometry. In contrast, vibrational spectroscopy using inelastic electron scattering unequivocally hints at strong molecule deformations on Ir(111) and at a planar adsorption geometry on graphene. The spectroscopic evidence for the different adsorption configurations is supported by density functional calculations.

5.
J Cell Biochem ; 113(1): 204-8, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21898541

RESUMEN

Several biological events are controlled by Hedgehog (Hh) signaling, including osteoblast phenotype development. This study aimed at evaluating the gene expression profile of human mesenchymal stem cells (hMSCs) treated with the Hh agonist, purmorphamine, focusing on Hh signaling and osteoblast differentiation. hMSCs from bone marrow were cultured in non-osteogenic medium with or without purmorphamine (2 µM) for periods of up to 14 days. Purmorphamine up-regulated gene expression of the mediators of Hh pathway, SMO, PTCH1, GLI1, and GLI2. The activation of Hh pathway by purmorphamine increased the expression of several genes (e.g., RUNX2 and BMPs) related to osteogenesis. Our results indicated that purmorphamine triggers Hh signaling pathway in hMSCs, inducing an increase in the expression of a set of genes involved in the osteoblast differentiation program. Thus, we conclude that Hh is a crucial pathway in the commitment of undifferentiated cells to the osteoblast lineage.


Asunto(s)
Proteínas Hedgehog/metabolismo , Células Madre Mesenquimatosas/metabolismo , Morfolinas/farmacología , Osteoblastos/citología , Purinas/farmacología , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/genética , Células Cultivadas , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Perfilación de la Expresión Génica , Proteínas Hedgehog/genética , Humanos , Factores de Transcripción de Tipo Kruppel/metabolismo , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , Proteínas Nucleares/metabolismo , Osteogénesis/genética , Receptores Patched , Receptor Patched-1 , ARN Mensajero/metabolismo , Receptores de Superficie Celular/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Transducción de Señal/genética , Receptor Smoothened , Factores de Transcripción/metabolismo , Proteína con Dedos de Zinc GLI1 , Proteína Gli2 con Dedos de Zinc
6.
J Comput Chem ; 33(12): 1165-78, 2012 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-22392924

RESUMEN

We have developed a complete set of self-consistent charge density-functional tight-binding parameters for ZnX (X = Zn, O, S, Se, Te, Cd, H, C, and N). The transferability of the derived parameters has been tested against Pseudo Potential-Perdew, Burke and Ernzerhof (PP-PBE) calculations and experimental values (whenever available) for corresponding bulk systems (e.g., hexagonal close packing, zinc-blende, and wurtzite(wz)), various kinds of nanostructures (such as nanowires, surfaces, and nanoclusters), and also some small molecular systems. Our results show that the derived parameters reproduce the structural and energetic properties of the above-mentioned systems very well. With the derived parameter set, one can study zinc-chalcogenide nanostructures of relatively large size which was otherwise prohibited by other methods. The Zn-Cd parametrization developed in this article will help in studying large semiconductor hetero-nanostructures of Zn and Cd chalcogenides such as ZnX/CdX core/shell nanoparticles, nanotubes, nanowires, and nanoalloys.


Asunto(s)
Cadmio/química , Calcógenos/química , Nanoestructuras/química , Semiconductores , Zinc/química , Modelos Moleculares , Simulación de Dinámica Molecular , Nanoestructuras/ultraestructura , Teoría Cuántica
7.
J Mater Sci Mater Med ; 22(1): 151-8, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21107658

RESUMEN

This study investigated the response of human alveolar bone-derived cells to a novel poly(vinylidene fluoride-trifluoroethylene)/barium titanate (P(VDF-TrFE)/BT) membrane. Osteoblastic cells were cultured in osteogenic conditions either on P(VDF-TrFE)/BT or polytetrafluoroethylene (PTFE) for up to 14 days. At 7 and 14 days, the mRNA expression of Runt-related transcription factor 2 (RUNX2), Type I collagen (COL I), Osteopontin (OPN), Alkaline phosphatase (ALP), Bone sialoprotein (BSP), and Osteocalcin (OC), key markers of the osteoblastic phenotype, and of Bcl2-associated X protein (Bax), B-cell CLL/lymphoma 2 (Bcl-2), and Survivin (SUR), associated with the control of the apoptotic cell death, was assayed by real-time PCR. In situ ALP activity was qualitatively evaluated by means of Fast red staining. Surface characterization was also qualitatively and quantitatively assayed in terms of topography, roughness, and wettability. Cells grown on P(VDF-TrFE)/BT exhibited a significantly higher mRNA expression for all markers compared to the ones on PTFE, except for Bcl-2, which was not detected for both groups. Additionally, Fast red staining was noticeably stronger in cultures on P(VDF-TrFE)/BT at 7 and 14 days. At micron- and submicron scale, SEM images and roughness analysis revealed that PTFE and P(VDF-TrFE)/BT exhibited a smooth topography and a similar roughness, respectively. PTFE membrane displayed higher contact angles compared with P(VDF-TrFE)/BT, as indicated by wettability assay. The novel P(VDF-TrFE)/BT membrane supports the acquisition of the osteoblastic phenotype in vitro, while up-regulating the expression of apoptotic markers. Further in vivo experiments should be carried out to confirm the capacity of P(VDF-TrFE)/BT membrane in promoting bone formation in guided bone regeneration.


Asunto(s)
Compuestos de Bario/química , Huesos/efectos de los fármacos , Membranas Artificiales , Polivinilos/química , Titanio/química , Alveolo Dental/citología , Apoptosis/efectos de los fármacos , Apoptosis/genética , Compuestos de Bario/farmacología , Regeneración Ósea/efectos de los fármacos , Regeneración Ósea/genética , Regeneración Ósea/fisiología , Huesos/citología , Huesos/metabolismo , Células Cultivadas , Subunidad alfa 1 del Factor de Unión al Sitio Principal/genética , Regulación de la Expresión Génica/efectos de los fármacos , Genes bcl-2/efectos de los fármacos , Regeneración Tisular Dirigida , Humanos , Osteoblastos/citología , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Osteoblastos/fisiología , Polivinilos/farmacología , Titanio/farmacología
8.
Oral Microbiol Immunol ; 24(1): 25-31, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19121066

RESUMEN

INTRODUCTION: Periapical chronic lesion formation involves activation of the immune response and alveolar bone resorption around the tooth apex. However, the overall roles of T helper type 1 (Th1), Th2, and T-regulatory cell (Treg) responses and osteoclast regulatory factors in periapical cysts and granulomas have not been fully determined. This study aimed to investigate whether different forms of apical periodontitis, namely cysts and granulomas, show different balances of Th1, Th2 regulators, Treg markers, and factors involved in osteoclast chemotaxis and activation. METHODS: Gene expression of these factors was assessed using quantitative real-time polymerase chain reaction, in samples obtained from healthy gingiva (n = 8), periapical granulomas (n = 20), and cysts (n = 10). RESULTS: Periapical cysts exhibited a greater expression of GATA-3, while a greater expression of T-bet, Foxp3, and interleukin-10 (IL-10) was seen in granulomas. The expression of interferon-gamma, IL-4, and transforming growth factor-beta was similar in both lesions. Regarding osteoclastic factors, while the expression of SDF-1alpha/CXCL12 and CCR1 was higher in cysts, the expression of RANKL was significantly higher in granulomas. Both lesions exhibited similar expression of CXCR4, CKbeta8/CCL23, and osteoprotegerin, which were significantly higher than in control. CONCLUSION: Our results showed a predominance of osteoclast activity in granulomas that was correlated with the Th1 response. The concomitant expression of Treg cell markers suggests a possible suppression of the Th1 response in granulomas. On the other hand, in cysts the Th2 activity is augmented. The mechanisms of periradicular lesion development are still not fully understood but the imbalance of immune and osteoclastic cell activity in cysts and granulomas seems to be critically regulated by Treg cells.


Asunto(s)
Osteoclastos/fisiología , Granuloma Periapical/inmunología , Quiste Radicular/inmunología , Linfocitos T Reguladores/inmunología , Células TH1/inmunología , Células Th2/inmunología , Adulto , Pérdida de Hueso Alveolar/inmunología , Pérdida de Hueso Alveolar/metabolismo , Quimiocina CCL3/biosíntesis , Quimiocina CXCL12/biosíntesis , Quimiocinas CC/biosíntesis , Quimiotaxis , Enfermedad Crónica , Factores de Transcripción Forkhead/biosíntesis , Factor de Transcripción GATA3/biosíntesis , Expresión Génica , Humanos , Interferón gamma/biosíntesis , Interleucina-10/biosíntesis , Persona de Mediana Edad , Osteoprotegerina/biosíntesis , Granuloma Periapical/metabolismo , Ligando RANK/biosíntesis , Quiste Radicular/metabolismo , Receptores CCR1/biosíntesis , Receptores CXCR4/biosíntesis , Proteínas de Dominio T Box/biosíntesis
9.
Oral Microbiol Immunol ; 24(1): 1-6, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19121062

RESUMEN

INTRODUCTION: Periodontal disease is a chronic inflammation of the attachment structures of the teeth, triggered by potentially hazardous microorganisms and the consequent immune-inflammatory responses. In humans, the T helper type 17 (Th17) lineage, characterized by interleukin-17 (IL-17) production, develops under transforming growth factor-beta (TGF-beta), IL-1beta, and IL-6 signaling, while its pool is maintained by IL-23. Although this subset of cells has been implicated in various autoimmune, inflammatory, and bone-destructive conditions, the exact role of T lymphocytes in chronic periodontitis is still controversial. Therefore, in this study we investigated the presence of Th17 cells in human periodontal disease. METHODS: Gingival and alveolar bone samples from healthy patients and patients with chronic periodontitis were collected and used for the subsequent assays. The messenger RNA expression for the cytokines IL-17, TGF-beta, IL-1beta, IL-6, and IL-23 in gingiva or IL-17 and receptor activator for nuclear factor-kappaB ligand in alveolar bone was evaluated by real-time polymerase chain reaction. The production of IL-17, TGF-beta, IL-1beta, IL-6, and IL-23 proteins was evaluated by immunohistochemistry and the presence of Th17 cells in the inflamed gingiva was confirmed by immunofluorescence confocal microscopy for CD4 and IL-17 colocalization. RESULTS: Our data demonstrated elevated levels of IL-17, TGF-beta, IL-1beta, IL-6, and IL-23 messenger RNA and protein in diseased tissues as well as the presence of Th17 cells in gingiva from patients with periodontitis. Moreover, IL-17 and the bone resorption factor RANKL were abundantly expressed in the alveolar bone of diseased patients, in contrast to low detection in controls. CONCLUSION: These results provided strong evidence for the presence of Th17 cells in the sites of chronic inflammation in human periodontal disease.


Asunto(s)
Pérdida de Hueso Alveolar/inmunología , Periodontitis Crónica/inmunología , Interleucina-17/biosíntesis , Linfocitos T Colaboradores-Inductores/inmunología , Adulto , Pérdida de Hueso Alveolar/metabolismo , Estudios de Casos y Controles , Femenino , Técnica del Anticuerpo Fluorescente , Expresión Génica , Humanos , Inmunohistoquímica , Interleucina-1beta/biosíntesis , Interleucina-23/biosíntesis , Interleucina-6/biosíntesis , Masculino , Microscopía Confocal , Ligando RANK/biosíntesis , ARN Mensajero/biosíntesis , Linfocitos T Colaboradores-Inductores/metabolismo , Factor de Crecimiento Transformador beta/biosíntesis
10.
Acta Ortop Mex ; 30(6): 311-315, 2016.
Artículo en Español | MEDLINE | ID: mdl-28549363

RESUMEN

BACKGROUND: Flail chest is managed with mechanical ventilation or inhaloteraphy and analgesia. Little has been published on the use of bioabsorbable material and its evolution in flail chest fixation. METHODS: This is a descriptive study of patients with unstable chest undergoing fixation with bioabsorbable plates and screws in a period from February 2009 to December 2011. RESULTS: We report 18 cases, aged 33-74 years (mean 53), three with bilateral involvement; rib fixation was performed between 1-21 days of the accident (mean 1.5). They started walking the next day in 14 cases; postoperative stay was four days (range 3-14). The heart rate of patients prior to surgery was 90 per minute (range 82-100) and lowered to 84 after fixation (range 82-92), preoperative respiratory rate was 26 per minute (range 22-28) and below 22 per minute (range 20 to 26) in postoperative period. CONCLUSIONS: The use of bioabsorbable material for osteosynthesis of costal fractures did not show side effects in our period of study.


ANTECEDENTES: El tórax inestable se trata con ventilación mecánica o inhaloterapia y analgesia. Poco se ha publicado sobre el uso de material bioabsorbible y su evolución en la fijación de tórax inestable. MÉTODOS: Estudio descriptivo de pacientes con tórax inestable sometidos a fijación con placas y tornillos bioabsorbibles en un período comprendido de Febrero de 2009 a Diciembre de 2011. RESULTADOS: Presentamos 18 casos con edades entre 33 y 74 años (media de 53), tres con tórax inestable bilateral; la fijación costal se realizó entre 1 y 21 días del accidente (media de 1.5). Se inició deambulación al día siguiente en 14 casos; la estancia postoperatoria fue de cuatro días (rango de 3 a 14). La frecuencia cardíaca de los pacientes previa a la cirugía era de 90 por minuto (rango 82 a 100) y bajó a 84 después de la fijación (rango 82 a 92); la frecuencia respiratoria preoperatoria era 26 por minuto (rango 22 a 28) y bajó a 22 por minuto (rango 20 a 26) en el postoperatorio. CONCLUSIONES: El uso de material bioabsorbible para osteosíntesis costal no tiene efectos secundarios atribuibles al material en el corto plazo.


Asunto(s)
Implantes Absorbibles , Placas Óseas , Tornillos Óseos , Tórax Paradójico , Adulto , Anciano , Tórax Paradójico/cirugía , Fijación Interna de Fracturas , Humanos , Persona de Mediana Edad , Fracturas de las Costillas
11.
Genetics ; 134(4): 1077-83, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8104159

RESUMEN

We propose a general restriction fragment length polymorphism-based strategy to analyze the distribution of meiotic crossover events throughout specific genetic intervals. We have isolated 64 recombinant chromosomes carrying independent meiotic crossover events in the genetic interval eth-1-un-2 on linkage group I of Neurospora crassa. Thirty-eight crossover events were physically mapped with reference to a 200-kb region cloned by chromosome walking, using N. crassa lambda and cosmid libraries. Crossovers were homogeneously distributed at intervals of 5.0 +/- 2.3 kb along the entire cloned interval. The ratio of physical to genetic distance appears to be higher in the region than in the overall N. crassa genome, suggesting that recombinational activity is less in large chromosomes than in small ones. The present work provides a method for defining the centromeric-telomeric orientation of single cloned DNA fragments. Their physical distance can also be estimated with respect to linked loci, provided that crossover events are distributed homogeneously in the interval. This strategy overcomes typical difficulties in defining the position and direction of chromosome walking steps on conventional linkage maps.


Asunto(s)
Intercambio Genético , Neurospora crassa/genética , Polimorfismo de Longitud del Fragmento de Restricción , Mapeo Cromosómico , Clonación Molecular , Cósmidos , Genes Fúngicos , Ligamiento Genético , Meiosis
12.
Genetics ; 142(3): 789-800, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8849888

RESUMEN

Intense biochemical and genetic research on the eth-1r mutant of Neurospora crassa suggested that this locus might encode S-adenosylmethionine synthetase (S-Adomet synthetase). We have used protoplast transformation and phenotypic rescue of a thermosensitive phenotype associated with the eth-1r mutation to clone the locus. Nucleotide sequence analysis demonstrated that it encodes S-Adomet synthetase. Homology analyses of prokaryotic, fungal and higher eukaryotic S-Adomet synthetase polypeptide sequences show a remarkable evolutionary conservation of the enzyme. N. crassa strains carrying S-Adomet synthetase coding sequences fused to a strong heterologous promoter were constructed to assess the phenotypic consequences of in vivo S-Adomet synthetase overexpression. Studies of growth rates and microscopic examination of vegetative development revealed that normal growth and morphogenesis take place in N. crassa even at abnormally high levels of cellular S-Adomet. The degree of cytosine methylation of a naturally methylated genomic region was dependent on the cellular levels of S-Adomet. We conclude that variation in S-Adomet levels in N. crassa cells, which in addition to the status of genomic DNA methylation could modify the flux of other S-Adomet-dependent metabolic pathways, does not affect growth rate or morphogenesis.


Asunto(s)
ADN de Hongos , Proteínas Fúngicas/genética , Genes Fúngicos , Metionina Adenosiltransferasa/genética , Neurospora crassa/enzimología , Alelos , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , ADN Complementario/aislamiento & purificación , Regulación Fúngica de la Expresión Génica , Prueba de Complementación Genética , Calor , Humanos , Datos de Secuencia Molecular , Neurospora crassa/genética , Péptidos/química , Fenotipo , Análisis de Secuencia , Homología de Secuencia de Aminoácido
13.
Genetics ; 144(4): 1455-62, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8978034

RESUMEN

eth-1r, a thermosensitive allele of the Neurospora crassa S-adenosylmethionine (AdoMet) synthetase gene that confers ethionine resistance, has been cloned and sequenced. Replacement of an aspartic amino acid residue (D48-->N48), perfectly conserved in prokaryotic, fungal and higher eukaryotic AdoMet synthetases, was found responsible for both thermosensitivity and ethionine resistance conferred by eth-1r. Gene fusion constructs, designed to overexpress eth-1r in vivo, render transformant cells resistant to ethionine. Dominance of ethionine resistance was further demonstrated in eth-1+/eth-1r partial diploids carrying identical gene doses of both alleles. Heterozygous eth-1+/eth-1r cells have, at the same time, both the thermotolerance conferred by eth-1+ and the ethionine-resistant phenotype conferred by eth-1r. AdoMet levels and AdoMet synthetase activities were dramatically decreased in heterozygous eth-1+/ eth-1r cells. We propose that this negative effect exerted by eth-1r results from the in vivo formation of heteromeric eth-1+/eth-1r AdoMet synthetase molecules.


Asunto(s)
Carcinógenos/toxicidad , Farmacorresistencia Microbiana/genética , Etionina/toxicidad , Metionina Adenosiltransferasa/genética , Neurospora crassa/genética , Alelos , Secuencia de Aminoácidos , Metionina/análogos & derivados , Datos de Secuencia Molecular , Mutación , Neurospora crassa/efectos de los fármacos
14.
Genetics ; 131(3): 575-80, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1352758

RESUMEN

P59Nc is a 59-kD polypeptide associated with 8-10-nm diameter cellular filaments in normal Neurospora crassa strains. Abnormally sized and shaped bundles of these structures are present in N. crassa strains carrying mutations at the locus sn (snowflake). By using molecular cloning and restriction fragment length polymorphism (RFLP) segregation analysis strategies we show here that sn is not the genetic locus of P59Nc. Several P59Nc cDNAs were cloned from a N. crassa lambda GT11 library after immunoscreening with specific polyclonal anti-P59Nc antibodies. Additional longer cDNAs were obtained from a N. crassa cDNA-lambda ZAP library. When used as probes in Southern blots of total DNA from wild-type strains, multicent-2 (a multiple mutant strain), and snowflake mutants, the P59Nc cDNAs revealed comparable patterns of hybridizing bands for all of the restriction enzymes tested. Analysis of segregation of BclI and ClaI RFLPs, detected in the genomic region of the P59Nc gene (locus cfp: cellular filament polypeptide), among a set of strains designed for RFLP mapping, or among selected progeny of crosses involving a snowflake parent, respectively, indicate that (i) there is in N. crassa a single cfp locus positioned on the right arm of linkage group VII between the locus for and the proximal breakpoint of the translocation T(VII----I)5936; (ii) the sn mutations in the centromere region of chromosome I do not represent translocations of cfp; and (iii) the snowflake mutants possesses a normal copy of the P59Nc gene on their chromosomes VII.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Proteínas Fúngicas/genética , Genes Fúngicos , Proteínas Asociadas a Microtúbulos/genética , Neurospora crassa/genética , Piruvato Descarboxilasa , Secuencia de Aminoácidos , Secuencia de Bases , Southern Blotting , Centrómero , Mapeo Cromosómico , Clonación Molecular , ADN de Hongos , Datos de Secuencia Molecular , Mutación , Polimorfismo de Longitud del Fragmento de Restricción , Translocación Genética
15.
J Dent ; 43(1): 110-6, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25446735

RESUMEN

OBJECTIVE: Fresh-frozen bone allograft (FFBA) is an alternative to autogenous bone (AB) for reconstructing maxillary bone. Despite the promising clinical results, cell responses to FFBA and AB were not evaluated. Thus, our aim was to compare cells harvested from maxillary reconstructed sites with either AB or FFBA in terms of osteoblast differentiation and to evaluate the effect of culturing cells in contact with FFBA. METHODS: Cells harvested from three patients submitted to bilateral maxillary reconstruction with AB and FFBA were cultured to evaluate: proliferation, alkaline phosphatase activity, extracellular matrix mineralization and gene expression of osteoblastic markers. The effect of FFBA on osteoblast differentiation was studied by culturing cells harvested from AB in contact with FFBA and evaluating the same parameters. Data were compared using either two-way ANOVA followed by Tukey-b test or Student's t test (p≤0.05). RESULTS: Cell proliferation was higher in cultures from AB grafted sites and extracellular matrix mineralization was higher in cultures derived from FFBA grafted sites. The gene expression of alkaline phosphatase, RUNX2, bone sialoprotein and osteocalcin was higher in cells derived from FFBA compared with cells from AB grafted sites. However, the exposure of cells derived from AB to FFBA particles did not have any remarkable effect on osteoblast differentiation. CONCLUSIONS: These results indicate the higher osteogenic activity of cells derived from FFBA compared with AB reconstructed sites, offering an explanation at cellular level of why FFBA could be a suitable alternative to AB for reconstructing maxillary bone defects.


Asunto(s)
Trasplante Óseo/métodos , Criopreservación , Reconstrucción Mandibular/métodos , Fosfatasa Alcalina/biosíntesis , Aloinjertos/trasplante , Regeneración Ósea/genética , Trasplante Óseo/efectos adversos , Diferenciación Celular/fisiología , Proliferación Celular/fisiología , Células Cultivadas , Femenino , Humanos , Persona de Mediana Edad , Osteoblastos/citología , Osteoblastos/fisiología , Osteocalcina/biosíntesis
16.
Gene ; 39(1): 55-9, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-3000893

RESUMEN

A technique has been developed that permits the packaging of mini-Mu-carrying cosmids into phage lambda heads. This procedure has several advantages over packaging into Mu helper capsids: the amounts of DNA to be packaged can be increased, the packaging efficiency is improved, and the stability of transducing lysates is high.


Asunto(s)
Bacteriófago lambda/genética , Bacteriófago mu/genética , Clonación Molecular/métodos , Cósmidos , Elementos Transponibles de ADN , Escherichia coli/genética , Vectores Genéticos , Operón Lac , Transducción Genética
17.
Gene ; 170(1): 155-6, 1996 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-8621082

RESUMEN

The structural gene encoding S-adenosyl-L-methionine synthetase (SAM-S) in the fungus Ascobolus immersus has been cloned and sequenced. It contains a 1179-bp ORF, interrupted by three introns, encoding a 393-amino-acid protein (42 978 Da) that is 90% homologous to the SAM-S of the filamentous fungus Neurospora crassa, indicating that these fungi are closely related species.


Asunto(s)
Ascomicetos/genética , Proteínas Fúngicas/genética , Genes Fúngicos , Metionina Adenosiltransferasa/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , ADN de Hongos/genética , Evolución Molecular , Datos de Secuencia Molecular , Neurospora crassa/genética , Especificidad de la Especie
18.
Gene ; 130(2): 253-8, 1993 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-8359692

RESUMEN

The fungus Neurospora crassa harbors large amounts of cytoplasmic filaments which are homopolymers of a 59-kDa polypeptide (P59Nc). We have used molecular cloning, sequencing and enzyme activity measurement strategies to demonstrate that these filaments are made of pyruvate decarboxylase (PDC, EC 4.1.1.1), which is the key enzyme in the glycolytic-fermentative pathway of ethanol production in fungi, and in certain plants and bacteria. Immunofluorescence analyses of 8-10-nm filaments, as well as quantitative Northern blot studies of P59Nc mRNA and measurements of PDC activity, showed that the presence and abundance of PDC filaments depends on the metabolic growth conditions of the cells. These findings may be of relevance to the biology of ethanol production by fungi, and may shed light on the nature and variable presence of filament bundles described in fungal cells.


Asunto(s)
Neurospora crassa/enzimología , Piruvato Descarboxilasa/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Northern Blotting , Catálisis , Clonación Molecular , Citoplasma/enzimología , ADN de Hongos , Genes Fúngicos , Datos de Secuencia Molecular , Piruvato Descarboxilasa/genética , ARN Mensajero/metabolismo , Homología de Secuencia de Aminoácido
19.
Br J Pharmacol ; 118(6): 1488-92, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8832076

RESUMEN

1. The effect of intracerebroventricular (i.c.v.) injection of bradykinin (BK) and related peptides was tested on the dental pulp electrical stimulation threshold (DPEST) in rats. 2. BK (4, 8 and 16 nmol) induced a dose-dependent increase of DPEST, indicative of an antinociceptive effect. 3. I.c.v. injection of equimolar doses of BK-related peptides, Lys-BK and Met-Lys-BK, also induced an increase of DPEST, but the magnitude of the effect was not as intensive as that induced by BK, when the maximum increase of DPEST was considered. The peptide T-kinin induced a short lasting and weak antinociceptive effect. 4. The B1 agonist, des-Arg9-BK (8 nmol) induced a significant antinociceptive effect, but this was not as intensive as that induced by BK. 5. The B2 antagonist D-Arg0-Hyp3-Thi5,8-D-Phe7-BK (D-Arg0) competitively antagonized the BK-induced antinociception. Likewise, Hyp3-Thi5,8-D-Phe7-BK (Hyp) also antagonized BK effect. However, the compound Thi5,8-D-Phe7-BK (Thi), initially considered a pure BK antagonist, induced an antinociceptive effect, supporting previous observations that this peptide can also act as a partial agonist. 6. It is concluded that the dose-dependent antinociceptive effect induced by i.c.v. injection of BK is mediated by the stimulation of brain B2 receptors.


Asunto(s)
Analgésicos/farmacología , Bradiquinina/farmacología , Receptores de Bradiquinina/efectos de los fármacos , Animales , Bradiquinina/agonistas , Bradiquinina/antagonistas & inhibidores , Antagonistas de los Receptores de Bradiquinina , Pulpa Dental/fisiología , Relación Dosis-Respuesta a Droga , Estimulación Eléctrica , Inyecciones Intraventriculares , Masculino , Umbral del Dolor/efectos de los fármacos , Ratas , Ratas Wistar
20.
JSLS ; 3(3): 197-201, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10527331

RESUMEN

Laparoscopic and thoracoscopic techniques have provided a new dimension in the correction of functional disorders of the esophagus. Therapeutic success, however, depends on the confirmation of esophageal disease as a cause of the symptoms, on understanding the basic cause of dysfunction and on identifying the surgical patient. This study is a retrospective study of patients submitted to surgery using the Lind procedure for gastroesophageal reflux disease (GERD). The purpose of this study is to establish the value of the routine use of esophageal manometry and 24-hour pH monitoring in order to select patients and perform pre and postoperative functional evaluation. Forty-one patients (68.3%) had a hypotonic lower esophageal sphincter. The average pressure was 9.2 mm Hg preoperatively and 15.2 mm Hg postoperatively, with an increase of 6.0 mm Hg. This increase was 8.8 mm Hg in hypotonics and 4.3 mm Hg in the normotonics. There was a certain degree of hypomotility of the esophageal body in 14 patients (23.3%) and, of this group, 4 (28.5%) improved postoperatively. Pathological acid reflux was found in 51 cases (85.0%) by pH monitoring. The mean of the preoperative DeMeester score was 31.4, later dropping to 3.2. Esophageal manometry and 24-hour pH monitoring are effective methods for revealing the level of functional modification established by anti-reflux surgery and for helping to objectively perform the selection.


Asunto(s)
Reflujo Gastroesofágico/diagnóstico , Reflujo Gastroesofágico/cirugía , Concentración de Iones de Hidrógeno , Manometría , Adolescente , Adulto , Anciano , Niño , Femenino , Fundoplicación/métodos , Reflujo Gastroesofágico/fisiopatología , Humanos , Laparoscopía/métodos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico/métodos , Selección de Paciente , Periodo Posoperatorio , Cuidados Preoperatorios , Estudios Retrospectivos , Sensibilidad y Especificidad , Resultado del Tratamiento
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