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1.
Sleep Med ; 109: 1-3, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37354730

RESUMEN

OBJECTIVE: while obstructive sleep apnea is strongly associated with incident cardiovascular diseases (CVD), the underlying mechanisms remain to be elucidated. This study aimed to compare the patterns of microRNAs expression between OSA and control patients with and without incident CVD. METHODS: 218 matched adult participants with and without OSA and with and without incident CVD were selected from two independent community-based prospective cohorts in France and Switzerland, and 168 microRNAs on average were detected per sample. OSA was diagnosed using the validated Berlin questionnaire in one study (Paris Prospective Study 3) and during a full-night polysomnography in the second study (HypnoLaus Study). RESULTS: there were 78 OSA patients (39 with and 39 without CVD) and 140 controls (70 with and 70 without CVD). Participants were male in 54.6% (n = 119) and mean age was 58.7 years (±9.2). Of the 183 miRNAs screened, a mean 168 assays were detected per sample, and 129 in all samples. There was no pattern of blood microRNAs expression that discriminated OSA patients with and without CVD events. CONCLUSIONS: this binational study failed to find any association between a large panel of microRNAs and OSA patients with and without incident CVD.


Asunto(s)
Enfermedades Cardiovasculares , MicroARNs , Apnea Obstructiva del Sueño , Adulto , Humanos , Masculino , Persona de Mediana Edad , Femenino , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/genética , Enfermedades Cardiovasculares/complicaciones , Estudios Prospectivos , Apnea Obstructiva del Sueño/epidemiología , Apnea Obstructiva del Sueño/genética , Apnea Obstructiva del Sueño/complicaciones , Polisomnografía , Factores de Riesgo
2.
J Dent Res ; 101(7): 859-869, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35148649

RESUMEN

Craniofacial and jaw bones have unique physiological specificities when compared to axial and appendicular bones. However, the molecular profile of the jaw osteoblast (OB) remains incomplete. The present study aimed to decipher the bone site-specific profiles of transcription factors (TFs) expressed in OBs in vivo. Using RNA sequencing analysis, we mapped the transcriptome of confirmed OBs from 2 different skeletal sites: mandible (Md) and tibia (Tb). The OB transcriptome contains 709 TF genes: 608 are similarly expressed in Md-OB and Tb-OB, referred to as "OB-core"; 54 TF genes are upregulated in Md-OB, referred to as "Md-set"; and 18 TF genes are upregulated in Tb-OB, referred to as "Tb-set." Notably, the expression of 29 additional TF genes depends on their RNA transcript variants. TF genes with no previously known role in OBs and bone were identified. Bioinformatics analysis combined with review of genetic disease databases and a comprehensive literature search showed a significant contribution of anatomical origin to the OB signatures. Md-set and Tb-set are enriched with site-specific TF genes associated with development and morphogenesis (neural crest vs. mesoderm), and this developmental imprint persists during growth and homeostasis. Jaw and tibia site-specific OB signatures are associated with craniofacial and appendicular skeletal disorders as well as neurocristopathies, dental disorders, and digit malformations. The present study demonstrates the feasibility of a new method to isolate pure OB populations and map their gene expression signature in the context of OB physiological environment, avoiding in vitro culture and its associated biases. Our results provide insights into the site-specific developmental pathways governing OBs and identify new major OB regulators of bone physiology. We also established the importance of the OB transcriptome as a prognostic tool for human rare bone diseases to explore the hidden pathophysiology of craniofacial malformations, among the most prevalent congenital defects in humans.


Asunto(s)
Regulación de la Expresión Génica , Osteoblastos , Humanos , Mandíbula , Cresta Neural , Osteoblastos/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
3.
J Dent Res ; 101(5): 526-533, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34875909

RESUMEN

Poor oral health has been linked to coronary heart disease (CHD). Clustering clinical oral conditions routinely recorded in adults may identify their CHD risk profile. Participants from the Paris Prospective Study 3 received, between 2008 and 2012, a baseline routine full-mouth clinical examination and an extensive physical examination and were thereafter followed up every 2 y until September 2020. Three axes defined oral health conditions: 1) healthy, missing, filled, and decayed teeth; 2) masticatory capacity denoted by functional masticatory units; and 3) gingival inflammation and dental plaque. Hierarchical cluster analysis was performed with multivariate Cox proportional hazards regression models and adjusted for age, sex, smoking, body mass index, education, deprivation (EPICES score; Evaluation of Deprivation and Inequalities in Health Examination Centres), hypertension, type 2 diabetes, LDL and HDL serum cholesterol (low- and high-density lipoprotein), triglycerides, lipid-lowering medications, NT-proBNP and IL-6 serum level. A sample of 5,294 participants (age, 50 to 75 y; 37.10% women) were included in the study. Cluster analysis identified 3,688 (69.66%) participants with optimal oral health and preserved masticatory capacity (cluster 1), 1,356 (25.61%) with moderate oral health and moderately impaired masticatory capacity (cluster 2), and 250 (4.72%) with poor oral health and severely impaired masticatory capacity (cluster 3). After a median follow-up of 8.32 y (interquartile range, 8.00 to 10.05), 128 nonfatal incident CHD events occurred. As compared with cluster 1, the risk of CHD progressively increased from cluster 2 (hazard ratio, 1.45; 95% CI, 0.98 to 2.15) to cluster 3 (hazard ratio, 2.47; 95% CI, 1.34 to 4.57; P < 0.05 for trend). To conclude, middle-aged individuals with poor oral health and severely impaired masticatory capacity have more than twice the risk of incident CHD than those with optimal oral health and preserved masticatory capacity (ClinicalTrials.gov NCT00741728).


Asunto(s)
Enfermedad Coronaria , Diabetes Mellitus Tipo 2 , Adulto , Anciano , HDL-Colesterol , Análisis por Conglomerados , Enfermedad Coronaria/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Factores de Riesgo
4.
Biomaterials ; 26(8): 839-48, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15353195

RESUMEN

Bioactive glasses, osteoproductive materials, have received considerable attention as bone graft substitutes in the treatment of bony defects. More recent strategies for achieving a predictable periodontal regeneration include the use of enamel matrix proteins, due to their role in the formation of bone tissue. The aim of our study is to examine the effects of these materials on the proliferation and differentiation of the mouse preosteoblastic cell line MC3T3-E1. Cells were cultured up to 28 days in contact with three types of granules: Bioglass 45S5 granules (BG), 45S5 granules coated with enamel matrix proteins (Emdogain) (BG/EMD), and a less reactive glass used as a control (60S). Phase contrast microscopic observations have shown that all substrates supported the growth of osteoblastic cells. Zones of differentiation were observed at an earlier stage in cultures of BG and BG/EMD. TEM observations revealed ultrastructural features very close to what is observed in vivo during intramembranous ossification with a direct bone apposition on the bioactive glasses. Total protein production was higher in the cultures with BG and BG/EMD. Northern Blot analysis revealed a stimulation of the transcription factor Cbfa1/Runx2 at day 13 in cultures of BG when compared to the two other cultures. Bone sialoprotein (early marker of differentiation) and osteocalcin (marker of late-stage differentiation) expression was increased in cultures with BG and BG/EMD when compared to 60S. Taken together, our findings indicate that Bioglass alone or combined with Emdogain, have the ability to support the growth of osteoblast-like cells in vitro and to promote osteoblast differentiation by stimulating the expression of major phenotypic markers. In addition, we noticed that the bioactive granules coated with Emdogain revealed significantly higher protein production than the bioactive granules alone at day 20.


Asunto(s)
Materiales Biomiméticos , Diferenciación Celular/fisiología , Osteoblastos/fisiología , Biomarcadores , Cerámica , Vidrio , Microscopía Electrónica , Microscopía de Contraste de Fase , Osteoblastos/citología , Osteoblastos/ultraestructura
5.
Mol Plant Microbe Interact ; 4(2): 173-81, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1932813

RESUMEN

Three pathogenesis-related (PR) proteins of tobacco are acidic isoforms of beta-1,3-glucanase (PR-2a, -2b, -2c). We have cloned and sequenced a partial cDNA clone (lambda FJ1) corresponding to one of the PR-2 beta-1,3-glucanases. A small gene family encodes the PR-2 proteins in tobacco, and similar genes are present in a number of plant species. We analyzed the stress and developmental regulation of the tobacco PR-2 beta-1,3-glucanases by using northern and western analyses and a new technique to assay enzymatic activity. Stress caused by both thiamine and tobacco mosaic virus (TMV) infection resulted in a dramatic increase in the levels of PR-2 mRNA, protein, and enzyme activities. The increased PR-2 gene expression in upper uninoculated leaves of plants infected with TMV also suggests a role in systemic acquired resistance. During floral development, a number of beta-1,3-glucanase activities were observed in all flower tissues. However, PR-2 polypeptides were observed only in sepal tissue. In contrast, an mRNA that hybridized to the PR-2 cDNA was present in stigma/style tissue and the sepals. Primer extension analysis confirmed the identity of the PR-2 mRNA in sepals, but indicated that the beta-1,3-glucanase gene expressed in the stigma/style of flowers was distinct from the PR-2 genes. The induction of PR-2 protein synthesis by both stress and developmental signals was accompanied by a corresponding increase in the steady-state levels of PR-2 mRNA, suggesting that PR-2 gene expression is regulated, in part, at the level of mRNA accumulation.


Asunto(s)
Regulación Enzimológica de la Expresión Génica , Nicotiana/genética , Proteínas de Plantas/genética , Plantas Tóxicas , beta-Glucosidasa/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , ADN , Electroforesis en Gel de Poliacrilamida , Glucano 1,3-beta-Glucosidasa , Datos de Secuencia Molecular , Familia de Multigenes , Enfermedades de las Plantas , Tiamina/fisiología , Nicotiana/crecimiento & desarrollo , Nicotiana/microbiología , Virus del Mosaico del Tabaco/fisiología , beta-Glucosidasa/metabolismo
6.
J Med Chem ; 19(6): 792-7, 1976 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-950648

RESUMEN

The synthesis is described of a series of cycloalkanoindoles, comprising tetrahydrocarbazoles, a cyclopentindole, and a cycloheptindole, all bearing an ethanamine side chain at position 1. The acute toxicities of these compounds were evaluated, as well as their potential antidepressant properties, using tests based on the prevention of ptosis induced by reserpine and tetrabenazine. 9-Ethyl-N,N1-trimethyl-1,2,3,4-tetrahydrocarbazole-1-ethanamine (AY-24 614) was found to be the most potent analogue, having an ED50 of 0.12 mg/kg ip in preventing reserpine-induced ptosis in mice and an ED50 at 3.3 mg/kg ip in preventing tetrabenazine-induced ptosis in rats.


Asunto(s)
Antidepresivos Tricíclicos/síntesis química , Carbazoles/síntesis química , Indoles/síntesis química , Animales , Antidepresivos Tricíclicos/farmacología , Antidepresivos Tricíclicos/toxicidad , Blefaroptosis/prevención & control , Carbazoles/farmacología , Carbazoles/toxicidad , Etilaminas/síntesis química , Etilaminas/farmacología , Etilaminas/toxicidad , Indoles/farmacología , Indoles/toxicidad , Dosificación Letal Mediana , Ratones , Ratas , Reserpina/antagonistas & inhibidores , Tetrabenazina/antagonistas & inhibidores
7.
J Med Chem ; 29(5): 648-54, 1986 May.
Artículo en Inglés | MEDLINE | ID: mdl-3084784

RESUMEN

The design and synthesis of a series of 3H-benz[e]indol-8-amines are described. Two of the compounds are potent, orally active dopaminergic agents as established by their ability to induce contralateral turning in rats with unilateral 6-hydroxydopamine-induced lesions of the nigrostriatal pathway, to induce ambulation in rats rendered akinetic by bilateral injections of 6-hydroxydopamine into the anterolateral hypothalamus, and to antagonize reserpine-induced catalepsy in mice. The dopamine agonist activity of the 3H-benz[e]indol-8-amines establishes that a pyrrolo ring and a phenolic hydroxyl group can interact similarly with the dopamine receptor and provides evidence for the existence of a hydrogen-bond acceptor nucleus on the dopamine receptor macromolecule that is involved in the behavioral manifestations of dopamine agonists.


Asunto(s)
Indoles/farmacología , Receptores Dopaminérgicos/metabolismo , Aminas/farmacología , Animales , Catalepsia/inducido químicamente , Cuerpo Estriado/efectos de los fármacos , Hidroxidopaminas/farmacología , Masculino , Ratones , Actividad Motora/efectos de los fármacos , Rotación Óptica , Oxidopamina , Ratas , Ratas Endogámicas , Reserpina/farmacología
8.
J Med Chem ; 19(6): 787-92, 1976 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-950647

RESUMEN

A novel series of acidic cycloalkanoindoles comprising tetrahydrocarbazole-, cyclopentindole-, and cycloheptindole-1-acetic acids has been synthesized via the Fischer indolization between a phenylhydrazine and a 1-alkyl-2-oxocycloalkaneacetic acid ester. These compounds were evaluated, orally, for their capacities to decrease estabished adjuvant arthritis in rats. The most active compound of the series was 1-ethyl-8-n-propyl-1,2,3,4-tetrahydrocarbazole-1-acetic acid (AY-24 873),which had an ED50 of 1.1 +/- 0.2 mg/kg. AY-24 873 was also studied orally in rats for its effect on the acute inflammatory response in the carrageenin paw edema test. It was found that AY-24 873 was about ten times more active against the chromic than against the acute models of inflammation used.


Asunto(s)
Antiinflamatorios/síntesis química , Carbazoles/síntesis química , Indoles/síntesis química , Animales , Antiinflamatorios/efectos adversos , Antiinflamatorios/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Carbazoles/efectos adversos , Carbazoles/uso terapéutico , Cicloheptanos/efectos adversos , Cicloheptanos/síntesis química , Cicloheptanos/uso terapéutico , Ciclopentanos/síntesis química , Ciclopentanos/uso terapéutico , Edema/tratamiento farmacológico , Indoles/efectos adversos , Indoles/uso terapéutico , Ratas , Úlcera Gástrica/inducido químicamente , Relación Estructura-Actividad
9.
J Med Chem ; 29(8): 1452-7, 1986 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3735312

RESUMEN

The syntheses of N,N-dimethyl-6,7,8,9-tetrahydro-3H,10H-pyrrolo[3,2-a] carbazol-7-amine (8), N,N-dimethyl-7,8,9,10-tetrahydro-11H-pyrido[3,2-a] carbazol-8-amine (9a), and the N,N,11-trimethyl analogue (9b) are described. The in vitro inotropic activity of these compounds, as well as the known cardiotonics amrinone and 7-hydroxycyclindole (7), was investigated. Compound 8, a pyrrolo analogue of 7, was devoid of inotropic activity, while the pyrido analogues 9 were equiactive to 7 and amrinone. These results suggest that the hydroxyl group of 7 functions as an H-bond acceptor, rather than a donor, and that on interaction of 7, and the pyrido analogues 9, with a common receptor, an orbital occupied by one of the oxygen lone pair electrons of 7 must assume the same orientation as the orbital occupied by the pyridine nitrogen lone pair.


Asunto(s)
Carbazoles/farmacología , Cardiotónicos/farmacología , Corazón/efectos de los fármacos , Aminopiridinas/farmacología , Amrinona , Animales , Carbazoles/síntesis química , Cardiotónicos/síntesis química , Gatos , Contracción Miocárdica/efectos de los fármacos , Estimulación Química , Relación Estructura-Actividad
10.
J Med Chem ; 21(12): 1225-31, 1978 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31480

RESUMEN

The synthesis of analogues of the antipsychotic drug butaclamol bearing chloro substituents on the benzene rings is described. On the basis of a perceived topographical similarity of a putative chlorophenylethylamine pharmacophore present in these analogues and in VUFB-10032 and doclothepin, agents related to octoclothepin which do not induce catalepsy, they have been tested for "noncataleptic" neuroleptic activity. None of the butaclamol analogues exhibit this type of activity. Depending on the position of the chlorine, the analogues either retained butaclamol-like activity or were inactive.


Asunto(s)
Antipsicóticos/síntesis química , Butaclamol/síntesis química , Dibenzocicloheptenos/síntesis química , Animales , Reacción de Prevención/efectos de los fármacos , Butaclamol/análogos & derivados , Butaclamol/farmacología , Catalepsia/inducido químicamente , Dextroanfetamina/antagonistas & inhibidores , Epinefrina/antagonistas & inhibidores , Epinefrina/toxicidad , Humanos , Espectroscopía de Resonancia Magnética , Masculino , Ratas , Conducta Estereotipada/efectos de los fármacos , Relación Estructura-Actividad
11.
J Med Chem ; 29(6): 1009-15, 1986 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3012084

RESUMEN

The synthesis of 5-[hydroxy-2-[(1-methyl-3-phenylpropyl)amino]ethyl]-1H-indole-7- carboxamide, 5, a pyrrolo analogue of labetalol, is described. Compound 5 was found to reduce blood pressure in spontaneously hypertensive rats with an ED50 of 5 mg/kg po, without causing any decrease in heart rate. Isolated tissue studies with 5 shows that it is a nonselective beta-adrenoceptor antagonist and that it is a weaker alpha-adrenoceptor antagonist with a relative selectivity for alpha 1-receptors. Additionally, the compound displayed significant beta-adrenoceptor intrinsic sympathomimetic activity. Evidence is presented that the beta-adrenoceptor antagonist and agonist properties of 5 are mediated via hydrogen-bond formation with the receptor.


Asunto(s)
Antihipertensivos/farmacología , Labetalol/análogos & derivados , Animales , Antihipertensivos/síntesis química , Presión Sanguínea/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Cobayas , Frecuencia Cardíaca/efectos de los fármacos , Enlace de Hidrógeno , Técnicas In Vitro , Ratas , Ratas Endogámicas SHR , Receptores Adrenérgicos beta/efectos de los fármacos , Relación Estructura-Actividad
12.
J Med Chem ; 29(8): 1457-60, 1986 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3735313

RESUMEN

The synthesis of 4-(2-heptyloxy)-7-[(Z)-(3-hydroxycyclohexyl)]indole (7) is described. Compound 7 was tested for analgesic properties in the phenylbenzoquinone writhing test and was found to be essentially devoid of activity. In contrast, cis-3-[4-(2-heptyloxy)-2-hydroxyphenyl]cyclohexanol (8), the analogue in which the pyrrolo ring is replaced by a hydroxyl group, had an ED50 of 8.3 mg/kg, sc, in the same model. The absence of bioisosterism between the pyrrolo ring and the phenolic hydroxyl group, in this instance, is discussed in terms of the circumstances that control the manifestation of bioisofunctionality between a pyrrolo ring and a phenolic hydroxyl group, which functions as a hydrogen-bond donor.


Asunto(s)
Analgésicos/síntesis química , Benzoquinonas , Indoles/síntesis química , Animales , Cromatografía en Capa Delgada , Indoles/farmacología , Espectroscopía de Resonancia Magnética , Masculino , Ratones , Quinonas , Relación Estructura-Actividad
13.
J Med Chem ; 32(10): 2273-6, 1989 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2571729

RESUMEN

The enantiomers of 6,7,8,9-tetrahydro-N,N-dimethyl-3H-benz[e]indol-8- amine (1a) were prepared and tested for their actions on central dopamine and serotonin (5-HT) receptors. The dopaminergic effects were shown to reside in the (1)-R enantiomer. It was shown that compound 1a and its (+)-R enantiomer possess potent central 5-HT1A receptor stimulating properties.


Asunto(s)
Encéfalo/metabolismo , Dopaminérgicos/metabolismo , Indoles/metabolismo , Actividad Motora/efectos de los fármacos , Receptores de Serotonina/efectos de los fármacos , Animales , Membrana Celular/metabolismo , Cuerpo Estriado/metabolismo , Isomerismo , Masculino , Ratas , Ratas Endogámicas , Receptores Dopaminérgicos , Receptores de Dopamina D1 , Receptores de Dopamina D2 , Receptores de Serotonina/metabolismo , Reserpina/farmacología , Relación Estructura-Actividad
14.
J Med Chem ; 31(6): 1244-50, 1988 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3373493

RESUMEN

The synthesis of cis-1-ethyl-1,3,4,9-tetrahydro-4-(phenylmethyl)pyrano[3,4-b]indole -1-acetic acid, pemedolac (USAN), is described. This compound has been found to be a potent analgesic agent in primary screening. Pemedolac has been resolved and the active (+)-enantiomer assigned a 1S,4R absolute configuration on the basis of a crystallographic analysis of its (S)-(-)-borneol ester.


Asunto(s)
Acetatos/síntesis química , Analgésicos/síntesis química , Ácidos Indolacéticos , Acetatos/farmacología , Analgésicos/farmacología , Animales , Antiinflamatorios/farmacología , Masculino , Ratones , Conformación Molecular , Ratas , Ratas Endogámicas , Relación Estructura-Actividad
15.
J Histochem Cytochem ; 36(11): 1403-11, 1988 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3049790

RESUMEN

We report the development of a cytochemical affinity technique for detection of galacturonic acids at the ultrastructural level. The highly purified gonad lectin from Aplysia depilans (AGL) was tagged with colloidal gold particles and used for labeling carbohydrates in resin-embedded sections of various plant and fungal tissues. Patterns of AGL binding sites were compared to those obtained with a D-galactose-specific lectin, Ricinus communis agglutinin I. Differences in labeling patterns were noted, indicating that the lectins exhibited differential carbohydrate binding. In addition, the considerable loss of labeling over isolated wheat coleoptile walls treated for removal of pectin, after incubation with the AGL-gold complex, strongly suggested an affinity of AGL for pectic substances. A series of cytochemical controls, including sugar inhibition tests, has proven the specificity of the technique and the high affinity of AGL towards galacturonic acids. The potential value of this new lectin for ultrastructural studies on cell wall pectic substances in plant biology and pathology is demonstrated.


Asunto(s)
Quelantes , Colorantes Fluorescentes , Hongos/análisis , Oro , Ácidos Hexurónicos/análisis , Lectinas , Plantas/análisis , Ácidos Urónicos/análisis , Candida albicans/análisis , Ricinus communis , Pared Celular/análisis , Coloides , Dimetilsulfóxido , Europio , Galectinas , Hemaglutininas , Microscopía Electrónica , Lectinas de Plantas , Plantas Tóxicas
16.
Eur Cell Mater ; 4: 61-9, 2002 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-14562247

RESUMEN

Bioactive glasses have been shown to stimulate osteogenesis both in vivo and in vitro. However, the molecular mechanisms underlying this process are still poorly understood. In this study, we have investigated the behaviour of osteoblast-like cells (MG63), cultured in the presence of bioglass particles. Three types of granules were used: 45S5 bioactive glass, 45S5 granules preincubated in tris buffer and 60S non-reactive glass, used as control. Phase contrast microscopy permitted step-by-step visualization of cell cultures in contact with the particles. Ultrastructural observations of undecalcified sections revealed direct contacts of the cells and an electron-dense layer located at the periphery of the material. Protein synthesis was evaluated biochemically and showed a gradual increase throughout the culture time in the three types of cultures. Alkaline phosphatase was detected in situ, in clusters of packed cells either in contact with the material or in the background cell layer. Semi-quantitative RT-PCR analysis of the main osteoblastic markers showed that gene expression was maintained in all three cultures. The fact that osteocalcin was not detected, supports the fact that the MG63 cell line is composed of less differentiated osteogenic cells rather than mature osteoblasts. We also demonstrated for the first time in this cell line, the expression of Msx-2, Dlx-3 and Dlx-7 homeogenes, known to regulate in vivo foetal skeletogenesis as well as adult skeletal regeneration. However, no significant differences could be recognised in the expression pattern of bone markers between the three types of cultures. Yet these preliminary results indicate that bioactive glasses provided a suitable environment for the growth and proliferation of osteoblasts in vitro, since no drastic changes in phenotype expression of pre-osteoblasts was noted.

18.
J Mater Sci Mater Med ; 19(5): 1861-9, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-17914625

RESUMEN

Titanium and its alloys are frequently used as dental and orthopaedic implants due to their high mechanical strength, low elastic modulus and biocompatibility. However, as these materials have a poor wear resistance, tribo-chemical reactions during use produce debris accumulation, resulting in adverse cellular responses. In that sense, amorphous based materials are potential candidates, considering their hardness and crack growth resistance. This paper reports on the structural characterization of the as-quenched Ti45Zr38Ni17 alloy. This system displays a duplex structure never mentioned before with a low dispersion of nanometric beta-phase particles in an amorphous matrix. Moreover, in order to explore the biocompatibility of such composite, primary osteoblasts cultures are used to analyse cell behaviour around and upon the metallic surface. Osteoblasts attach and proliferate on the material as demonstrated by scanning electron microscopy. Cell proliferation and bone nodule formation are also observed in cultures with Ti45Zr38Ni17 particles by phase contrast microscope. In addition, transmission electron microscopy reveals ultrastructural features very close to those observed in vivo during intramembranous ossification with active osteoblasts surrounded by an extracellular matrix and a mineralized one. In conclusion, these results demonstrate that osteoblasts, cultured in presence of Ti45Zr38Ni17 alloy, proliferate, differentiate and synthesize bone matrix.


Asunto(s)
Materiales Biocompatibles Revestidos , Osteoblastos/metabolismo , Titanio/química , Aleaciones/química , Animales , Animales Recién Nacidos , Huesos/metabolismo , Proliferación Celular , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Microscopía de Contraste de Fase , Ratas , Ratas Sprague-Dawley , Difracción de Rayos X
19.
Biochem Cell Biol ; 73(5-6): 307-9, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8829378

RESUMEN

By assaying lysozyme activity after denaturing polyacrylamide gel electrophoresis of commercial hen egg white lysozyme preparations, minor lysozymal activity was detected as an 18-kDa protein. After electrophoretic purification for microsequencing, the N-terminus sequence of the 18-kDa lysozyme was found to be identical with mature 14.4-kDa hen egg white lysozyme. The 18-KDa hen egg white lysozyme was judged to be glycosylated based on 3.6-kDa decrease in molecular mass after N-glycosidase F treatment, binding to concanavalin A-Sepharose, and staining with periodate-Schiff's reagent. The minor form corresponded to about 0.3% of lysozyme molecules.


Asunto(s)
Proteínas del Huevo/metabolismo , Muramidasa/metabolismo , Animales , Pollos , Glicosilación
20.
Can J Microbiol ; 35(8): 749-53, 1989 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2819603

RESUMEN

Cell walls from various Gram-positive bacteria were incorporated at a concentration of 0.2% (w/v) into polyacrylamide gels as a substrate for detection of cell wall hydrolases. Bacterial extracts from crude cell wall preparations were denatured with sodium dodecyl sulfate and 2-mercaptoethanol and subjected to denaturing polyacrylamide gel electrophoresis in gels containing bacterial cell walls. After renaturation in the presence of purified and buffered 1% (v/v) Triton X-100, cell wall hydrolases were visualized as clear lytic zones against the opaque cell wall background. One to fifteen bands with lytic activity could be detected, depending on bacterial extracts and on the nature of the cell walls incorporated into gels. Crude cell wall extracts were the best source of cell wall hydrolases from various Gram-positive bacteria such as Clostridium perfringens (15 bands), Micrococcus luteus (1 band), Bacillus megaterium (4 bands), Bacillus sp. (6 bands), B. cereus (3 bands), B. subtilis (7 bands), Staphylococcus aureus (13 bands), Streptococcus faecalis (3 bands), and Strep. pyogenes (5 bands). Molecular masses of cell wall hydrolases ranged from 17 to 114.6 kDa. Lytic activities against cell walls of Corynebacterium sepedonicum (Clavibacter michiganense pv. sepedonicum) could be shown with the cell wall extracts of Strep. pyogenes (45.7 kDa), Strep. faecalis (67 kDa), B. megaterium (67 kDa), and Staph. aureus (67 kDa).


Asunto(s)
Bacterias Grampositivas/enzimología , Hidrolasas/análisis , Pared Celular/enzimología , Pared Celular/metabolismo , Electroforesis en Gel de Poliacrilamida/métodos , Bacterias Grampositivas/metabolismo , Hidrolasas/metabolismo , Desnaturalización Proteica
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