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1.
Tech Coloproctol ; 24(5): 479-486, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32193667

RESUMEN

BACKGROUND: The Echelon circular™ powered stapler (ECP stapler) obviates the need for manual firing of conventional circular staplers during the construction of a colorectal anastomosis, but has not been evaluated clinically. The aim of this study was to perform a clinical evaluation of this stapler. METHODS: A retrospective review of the initial clinical experience of a single surgeon using the ECP stapler for left-sided colorectal anastomosis construction during elective colorectal resections for benign and malignant disease was conducted by analyzing results from a prospectively maintained study database. Additionally, four attending colorectal and/or general surgeons who had performed ≥ 5 colorectal operations with the ECP stapler were invited to complete an anonymous online survey to subjectively assess the user experience with the device. Statistical analysis was conducted using Microsoft Excel Version 15.33. RESULTS: Seventeen patients underwent left-sided anastomotic reconstruction using the ECP stapler. All donuts (proximal and distal) were intact. Anastomotic integrity was evaluated using the air-leak test utilizing flexible video sigmoidoscopy. No leaks were observed, although one patient (5.9%) developed a postoperative pelvic abscess. The anonymous survey was completed by all four surgeons. Subjective evaluation of the ECP stapler suggests that the overall stapling quality, overall device ease-of-use, and the overall perception of anastomotic quality as above average when compared to manual 'end-to-end anastomosis' (EEA) stapling devices. CONCLUSIONS: In an initial clinical evaluation of the ECP stapler, the safety and ease-of-use of the device appears to be satisfactory. Powered stapling and the design of '3D stapling' may provide advantages over manual systems, and may improve the construction quality of left-sided colorectal anastomosis.


Asunto(s)
Neoplasias Colorrectales , Grapado Quirúrgico , Anastomosis Quirúrgica , Neoplasias Colorrectales/cirugía , Humanos , Recto/cirugía , Estudios Retrospectivos , Engrapadoras Quirúrgicas
2.
Phytother Res ; 30(1): 49-57, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26514663

RESUMEN

Hypercholesterolemia is a metabolic disorder characterized by high levels of low-density lipoprotein and blood cholesterol, causing inflammatory lesion. Purinergic signaling modulates the inflammatory and immune responses through adenine nucleotides and nucleoside. Guaraná has hypocholesterolemic and antiinflammatory properties. Considering that there are few studies demonstrating the effects of guaraná powder on the metabolism of adenine nucleotides, we investigated its effects on the activity of ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase) and ecto-adenosine deaminase activity in lymphocytes of rats with diet-induced hypercholesterolemia. The rats were divided into hypercholesterolemic and normal diet groups. Each group was subdivided by treatment: saline, guaraná powder 12.5, 25, or 50 mg/kg/day and caffeine concentration equivalent to highest dose of guaraná, fed orally for 30 days. An increase in adenosine triphosphate hydrolysis was observed in the lymphocytes of rats with hypercholesterolemia and treated with 25 or 50 mg/kg/day when compared with the other groups. The hypercholesterolemic group treated with the highest concentration of guaraná powder showed decreased ecto-adenosine deaminase activity compared with the normal diet groups. Guaraná was able to reduce the total cholesterol and low-density lipoprotein cholesterol to basal levels in hypercholesterolemic rats. High concentrations of guaraná associated with a hypercholesterolemic diet are likely to have contributed to the reduction of the inflammatory process.


Asunto(s)
Cafeína/farmacología , Hipercolesterolemia/tratamiento farmacológico , Paullinia/química , Teobromina/farmacología , Teofilina/farmacología , Adenosina Desaminasa/metabolismo , Animales , Colesterol/sangre , LDL-Colesterol/sangre , Dieta Alta en Grasa , Linfocitos/enzimología , Masculino , Preparaciones de Plantas/farmacología , Ratas , Ratas Wistar
3.
Parasitol Res ; 107(5): 1163-71, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20680343

RESUMEN

The proline-rich inhibitor of 31 kDa (PI31) is highly conserved through metazoan evolution, and its activity in the proteasome inhibition is well-established although the precise mechanism of inhibition is unclear. The coding DNA sequence of Schistosoma mansoni PI31 (SmPI31) was cloned, and the recombinant protein was expressed in bacterial system. The correct amino acid sequence was confirmed by mass spectrometry and circular dichroism suggests that SmPI31 contains both α-helix and non-structured regions. Inhibition assays, using the Suc-Leu-Leu-Val-Tyr-4-MCA substrate for proteasome degradation, showed that the S. mansoni proteasome may be regulated by the inhibitory activity of SmPI31. A gene expression assay using qRT-PCR at various stages during the S. mansoni life cycle has shown that SmPI31 transcripts are expressed in all studied stages, suggesting that PI31 plays an important role during the developmental processes of the parasite. In this study first evidence is presented that PI31 has a conserved structure and plays a role as proteasome inhibitor in adult worms and it is expressed through life cycle.


Asunto(s)
Inhibidores de Cisteína Proteinasa/biosíntesis , Perfilación de la Expresión Génica , Inhibidores de Proteasoma , Proteínas Protozoarias/biosíntesis , Schistosoma mansoni/enzimología , Animales , Dicroismo Circular , Clonación Molecular , Inhibidores de Cisteína Proteinasa/química , Inhibidores de Cisteína Proteinasa/genética , Expresión Génica , Ratones , Ratones Endogámicos BALB C , Conformación Proteica , Proteínas Protozoarias/química , Proteínas Protozoarias/genética , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Schistosoma mansoni/genética
4.
Cancer Radiother ; 24(8): 834-841, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33191120

RESUMEN

PURPOSE: Neoadjuvant chemoradiotherapy (nCRT) followed by surgery in patients with resectable esophageal or esophagogastric junctional (GEJ) (Siewert I) cancer is associated with long term overall survival benefits. Up to one third of all patients submitted to nCRT present pathological complete response (pCR). 18F-fluorodeoxyglucose positron emission tomography with CT (18F-FDG PET-CT) is an important tool for assessing treatment response. Purpose was to assess retrospectively the power of 18F-FDG PET-CT in predicting pCR to evaluate the feasibility of a "watch and wait" approach. PATIENTS AND METHODS: Retrospective analysis of a prospective database with esophageal or GEJ submitted to pre-operative chemoradiation. Pre and pos treatment 18F-FDG PET-CT were reviewed and classified using visual assessment and PERCIST criteria and the values of maximum standard uptake value were also recorded. Patients were classified as pCR or non-PCR. 18F-FDG PET-CT and pathological findings were compared against each other. RESULTS: Forty-three patients were included. The median age was 67 years and 90.7% were male. All patients underwent preoperative CRT and were evaluated with 18F-FDG PET-CT pre and post treatment. Transthoracic surgery was performed in all patients. Histological type was adenocarcinoma in 37% and squamous cell carcinoma in 58%. pCR was achieved in 56% of cases. Visual assessment of 18F-FDG PET-CT showed overall sensitivity 57.9%, specificity 62.5% and PERCIST criteria had 100% sensibility and 16.7% specificity. CONCLUSIONS: 18F-FDG PET-CT is not an ideal predictor of pCR but if we use the PERCIST criteria we will have a high sensitivity and negative predictive value, avoiding false negative scans.


Asunto(s)
Quimioradioterapia Adyuvante/métodos , Neoplasias Esofágicas/terapia , Unión Esofagogástrica , Terapia Neoadyuvante/métodos , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adenocarcinoma/terapia , Anciano , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/terapia , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/mortalidad , Neoplasias Esofágicas/patología , Femenino , Fluorodesoxiglucosa F18 , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Cuidados Preoperatorios , Radiofármacos , Estudios Retrospectivos , Sensibilidad y Especificidad , Resultado del Tratamiento , Espera Vigilante
5.
J Cell Biol ; 97(1): 22-9, 1983 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6134736

RESUMEN

Chinese hamster ovary (CHO) cell mutants resistant to the cytotoxic effects of taxol and requiring the drug for normal growth were isolated in a single step. One of these mutant cell lines, Tax-18, fails to divide in the absence of taxol; instead, the cells become larger, rounder, flatter, and multinucleated. Analysis by flow cytometry indicates that during taxol deprivation there is an accumulation of cells in G2 + M phase but that the cells are able to leak through the block in the absence of cell division and further increase their DNA content beyond the tetraploid amount. This interpretation is confirmed by karyotype analysis and by time-lapse studies that show cells rounded for mitosis two to five times longer than in wild-type cultures or in Tax-18 cultures grown in taxol. The cells finally attempt to undergo cytokinesis, fail, and spread out again, but as larger cells than before. Tax-18 has a normal growth rate and morphology when grown in taxol even at concentrations three to five times below the selecting concentration of the drug. The cells, however, have increased sensitivity to microtubule-disrupting drugs such as colcemid, griseofulvin, and D2O. The mutation for taxol auxotrophy behaves recessively in somatic cell hybridization experiments, and the phenotypic reversion rate is approximately 10(-5) in a nonmutagenized population. Both alpha- and beta-tubulin are present in apparently normal amounts and with normal electrophoretic mobilities on two-dimensional gels. The results suggest that Tax-18 lacks a factor necessary for mitosis and that taxol may be able to substitute for this factor.


Asunto(s)
Alcaloides/farmacología , División Celular/efectos de los fármacos , Mutación , Animales , Línea Celular , Cricetinae , ADN/biosíntesis , Demecolcina/farmacología , Deuterio/farmacología , Óxido de Deuterio , Relación Dosis-Respuesta a Droga , Femenino , Griseofulvina/farmacología , Células Híbridas/efectos de los fármacos , Paclitaxel , Fenotipo , Biosíntesis de Proteínas , Agua/farmacología
6.
J Cell Biol ; 102(4): 1522-31, 1986 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2870070

RESUMEN

Chinese hamster ovary cell mutants resistant to the microtubule stabilizing drug taxol were isolated in a single step. Of these 139 drug-resistant mutants, 59 exhibit an absolute requirement for taxol for normal growth and division, 13 have a partial requirement, and 69 grow normally without the drug. Two-dimensional gel analysis of whole cell proteins reveal "extra" spots representing altered tubulins in 13 of the mutants. Six of these have an altered alpha-tubulin and seven have an altered beta-tubulin. Cells with an absolute dependence on taxol become large and multinucleated when deprived of the drug. In contrast, partially dependent cells exhibit some multinucleation, but most cells appear normal. In one mutant that has an absolute dependence on taxol, the cells appear to die more quickly and their nuclei do not increase in size or number. As previously found for another taxol-dependent mutant (Cabral, F., 1983, J. Cell. Biol., 97:22-29), the taxol dependence of the mutants described in this paper behaves recessively in somatic cell hybrids, and the cells are more susceptible to being killed by colcemid than are the wild-type parental cells. When compared with wild-type cells, taxol-dependent mutants have normal arrays of cytoplasmic microtubules but form much smaller mitotic spindles in the presence of taxol. When deprived of the drug, however, these mutants cannot complete assembly of the mitotic spindle apparatus, as judged by tubulin immunofluorescence. Thus, the defects leading to taxol dependence in these mutants with defined alterations in alpha- and beta-tubulin appear to result from the cell's inability to form a functional mitotic spindle. Reversion analysis indicates that the properties of at least one alpha-tubulin mutant are conferred by the altered tubulin seen on two-dimensional gels.


Asunto(s)
Alcaloides/farmacología , Microtúbulos/efectos de los fármacos , Mutación , Tubulina (Proteína)/biosíntesis , Animales , División Celular/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Células Clonales , Cricetinae , Cricetulus , Femenino , Técnica del Anticuerpo Fluorescente , Cinética , Ovario , Paclitaxel , Tubulina (Proteína)/aislamiento & purificación
7.
J Cell Biol ; 103(5): 1855-61, 1986 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3536955

RESUMEN

A pool of 10 calmodulin-binding proteins (CBPs) was isolated from Chinese hamster ovary (CHO) cells via calmodulin (CaM)-Sepharose affinity chromatography. One of these ten isolated CBPs with a molecular mass of 52 kD was also found to be present in isolated CHO cell mitotic spindles. Affinity-purified antibodies generated against this pool of isolated CBPs recognize a single 52-kD protein in isolated CHO cell mitotic spindles by immunoblot analysis. Immunofluorescence examination of CHO, 3T3, NRK, PTK-2, and HeLa cells resulted in a distinct pattern of mitotic spindle fluorescence. The localization pattern of this 52-kD CBP directly parallels that of CaM in the spindle apparatus throughout the various stages of mitosis. Interestingly, there was no association of this 52-kD CBP with cytoplasmic microtubules. As is the case with CaM, the localization pattern of the 52-kD CBP in interphase cells is diffuse within the cytoplasm and is not associated with any discrete, cellular structures. This 52-kD CBP appears to represent the first mitotic spindle-specific calmodulin-binding protein identified and represents an initial step toward the ultimate determination of CaM function in the mitotic spindle apparatus.


Asunto(s)
Proteínas de Unión a Calmodulina/metabolismo , Calmodulina/metabolismo , Mitosis , Huso Acromático/metabolismo , Animales , Línea Celular , Cricetinae , Técnica del Anticuerpo Fluorescente , Peso Molecular
8.
J Cell Biol ; 135(6 Pt 1): 1525-34, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8978820

RESUMEN

A Chinese hamster alpha-tubulin cDNA was modified to encode an 11-amino acid carboxyl-terminal extension containing the immunodominant epitope from influenza hemagglutinin antigen (to create HA alpha 1-tubulin) and was cloned into a vector for expression in mammalian cells. 12 stable CHO cell lines expressing this HA alpha 1-tubulin were isolated and characterized. HA alpha 1-tubulin incorporated into all classes of microtubules, assembled to the same extent as the endogenous tubulin, and did not perturb the growth of the cells in which it was expressed. However, overexpression of HA alpha 1-tubulin strongly repressed the synthesis of endogenous alpha-tubulin while having little or no effect on the synthesis of beta-tubulin. Treatment of transfected cells with sodium butyrate to induce even greater expression of HA alpha 1-tubulin led to a further decrease in synthesis of endogenous alpha-tubulin that was fully reversible upon removal of the inducer. Decreased synthesis of alpha-tubulin in transfected cells did not result from decreased levels of alpha-tubulin mRNA, as demonstrated by ribonuclease protection assays. On the other hand, colchicine, a drug previously shown to destabilize the tubulin message, caused a clear reduction in both protein synthesis and mRNA levels for transfected HA alpha 1-tubulin and endogenous alpha-tubulin, thus indicating that the decreased alpha-tubulin synthesis observed as a result of HA alpha 1-tubulin overexpression is distinct from the previously described autoregulation of tubulin. The results are consistent with a mechanism in which free alpha-tubulin inhibits the translation of its own message as a way of ensuring stoichiometric synthesis of alpha- and beta-tubulin.


Asunto(s)
Regulación de la Expresión Génica , Biosíntesis de Proteínas , Tubulina (Proteína)/biosíntesis , Secuencia de Aminoácidos , Animales , Células CHO , Clonación Molecular , Colchicina/farmacología , Cricetinae , Cricetulus , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Datos de Secuencia Molecular , Biosíntesis de Proteínas/efectos de los fármacos , ARN Mensajero/metabolismo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Transfección , Tubulina (Proteína)/genética , Tubulina (Proteína)/fisiología
9.
J Cell Biol ; 97(1): 30-9, 1983 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6134737

RESUMEN

In the accompanying paper (Cabral, F., 1982, J. Cell. Biol., 97:22-29) we described the isolation and properties of taxol-requiring mutants of Chinese hamster ovary cells. We now show that at least one of these mutants, Tax-18, has an impaired ability to form a spindle apparatus. Immunofluorescence studies using antibodies to tubulin demonstrate that, when incubated in the absence of taxol, Tax-18 forms only a rudimentary spindle with few and shortened microtubules associated with the spindle poles. Furthermore, midbodies were not observed, consistent with an absence of cytokinesis. Essentially normal spindles and midbodies are seen in the presence of taxol. Electron microscopic examination indicates that centrioles and kinetochores are morphologically normal in the mutant strain. Pole-to-kinetochore microtubules were seen but interpolar microtubules were not. Taxol-deprived mutant cells stained with anti-centrosome serum show an elevated centriole content, indicating that the defect in Tax-18 does not affect centriole replication or prevent progression through the cell cycle. Although Tax-18 cells do not form a complete spindle in the absence of taxol, cytoplasmic microtubule assembly occurs in association with microtubule-organizing centers, and microtubules with apparently normal morphology exist throughout the cytoplasm. Observation of chromosome movement indicates that the defect in these cells occurs after prometaphase. These studies demonstrate that the formation of spindle microtubules requires cellular conditions that are different from those required for cytoplasmic microtubule formation. They further show that a normal spindle may be necessary for cytokinesis but not for progress of the cells through the cell cycle.


Asunto(s)
Alcaloides/farmacología , Microtúbulos/efectos de los fármacos , Mitosis/efectos de los fármacos , Animales , Línea Celular , Centriolos/fisiología , Centriolos/ultraestructura , Centrómero/ultraestructura , Cromosomas/fisiología , Cricetinae , Femenino , Microscopía Electrónica , Microtúbulos/metabolismo , Microtúbulos/ultraestructura , Mutación , Ovario , Paclitaxel
10.
J Cell Biol ; 97(4): 1055-61, 1983 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6619186

RESUMEN

Two Chinese hamster ovary cell lines with mutated beta-tubulins (Grs-2 and Cmd-4) and one that has a mutation in alpha-tubulin (Tax-1) are temperature sensitive for growth at 40.5 degrees C. To determine the functional defect in these mutant cells at the nonpermissive temperature, they were characterized with respect to cell cycle parameters and microtubule organization and function after relatively short periods at 40.5 degrees C. At the nonpermissive temperature all the mutants had normal appearing cytoplasmic microtubules. Premature chromosome condensation analysis failed to show any discrete step in the interphase cell cycle in which these mutants are arrested. These cells, however, show several defects at the nonpermissive temperature that appear related to the function of microtubules during mitosis. Time-lapse studies showed that mitosis was lengthened in the three mutant lines at 40.5 degrees C as compared with the wild-type cells at this temperature, resulting in a higher proportion of cells in mitosis after temperature shift. There was also a large increase in multinucleated cells in mutant populations after incubation at the nonpermissive temperature. Immunofluorescent studies using a monoclonal anti--alpha-tubulin antibody showed that the mutant cells had a high proportion of abnormal spindles at the nonpermissive temperature. The two altered beta-tubulins and the altered alpha-tubulin all were found to cause a similar phenotype at the high temperature that results in mitotic delay, defective cytokinesis, multinucleation, and ultimately, cell death. We conclude that spindle formation is the limiting microtubule function in these mutant cell lines at the nonpermissive temperature and that these cell lines will be of value for the study of the precise role of tubulin in mammalian spindle formation.


Asunto(s)
Huso Acromático/ultraestructura , Tubulina (Proteína)/fisiología , Animales , Línea Celular , Núcleo Celular/ultraestructura , Supervivencia Celular , Cricetinae , Femenino , Interfase , Microtúbulos/ultraestructura , Índice Mitótico , Mutación , Ovario , Temperatura , Tubulina (Proteína)/genética
11.
J Cell Biol ; 126(4): 1017-29, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7519616

RESUMEN

To study the effects of microtubule-associated proteins (MAPs) on in vivo microtubule assembly, cDNAs containing the complete coding sequences of a Drosophila 205-kD heat stable MAP, human MAP 4, and human tau were stably transfected into CHO cells. Constitutive expression of the transfected genes was low in most cases and had no obvious effects on the viability of the transfected cell lines. High levels of expression, as judged by Western blots, immunofluorescence, and Northern blots, could be induced by treating cells with sodium butyrate. High levels of MAPs were maintained for at least 24-48 h after removal of the sodium butyrate. Immunofluorescence analysis indicated that all three MAPs bound to cellular microtubules, but only the transfected tau caused a rearrangement of microtubules into bundles. Despite high levels of expression of these exogenous MAPs and the bundling of microtubules in cells expressing tau, transfected cells had normal levels of assembled and unassembled tubulin. With the exception of the tau-induced bundles, microtubules in transfected cells showed the same sensitivity as control cells to microtubule depolymerization by Colcemid. Further, all three MAPs were ineffective in reversing the taxol-dependent phenotype of a CHO mutant cell line. The absence of a quantitative effect of any of these heterologous proteins on the assembly of tubulin suggests that these MAPs may have different roles in vivo from those inferred previously from in vitro experiments.


Asunto(s)
Proteínas Asociadas a Microtúbulos/biosíntesis , Microtúbulos/ultraestructura , Animales , Northern Blotting , Western Blotting , Butiratos/toxicidad , Ácido Butírico , Células CHO , Cricetinae , Drosophila , Resistencia a Medicamentos , Técnica del Anticuerpo Fluorescente , Humanos , Proteínas Asociadas a Microtúbulos/análisis , Proteínas Asociadas a Microtúbulos/metabolismo , Microtúbulos/fisiología , ARN/biosíntesis , ARN/metabolismo , Proteínas Recombinantes/análisis , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/metabolismo , Transfección , Proteínas tau/análisis , Proteínas tau/biosíntesis , Proteínas tau/metabolismo
12.
Br J Pharmacol ; 153(2): 240-51, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18037916

RESUMEN

Recently, it has been recognized that the cannabinoid receptor CB2 may play a functionally relevant role in the central nervous system (CNS). This role is mediated primarily through microglia, a resident population of cells in the CNS that is morphologically, phenotypically, and functionally related to macrophages. These cells also express the cannabinoid receptor CB1. The CB1 receptor (CB1R) is constitutively expressed at low levels while the CB2 receptor (CB2R) is expressed at higher levels and is modulated in relation to cell activation state. The relatively high levels of the CB2R correspond with microglia being in 'responsive' and 'primed' states, suggesting the existence of a 'window' of functional relevance during which activation of the CB2R modulates microglial activities. Signature activities of 'responsive' and 'primed' microglia are chemotaxis and antigen processing, respectively. The endocannabinoid 2-arachidonylglycerol has been reported to stimulate a chemotactic response from these cells through the CB2R. In contrast, we have shown in vivo and in vitro that the exogenous cannabinoids delta-9-tetrahydrocannabinol and CP55940 inhibit the chemotactic response of microglia to Acanthamoeba culbertsoni, an opportunistic pathogen that is the causative agent of Granulomatous Amoebic Encephalitis, through activation of the CB2R. It is postulated that these exogenous cannabinoids superimpose an inhibitory effect on pro-chemotactic endocannabinoids that are elicited in response to Acanthamoeba. Furthermore, the collective results suggest that the CB2R plays a critical immune functional role in the CNS.


Asunto(s)
Química Encefálica/fisiología , Inmunidad/fisiología , Receptor Cannabinoide CB2/fisiología , Animales , Química Encefálica/inmunología , Sistema Nervioso Central/inmunología , Sistema Nervioso Central/metabolismo , Quimiotaxis/inmunología , Quimiotaxis/fisiología , Humanos , Macrófagos/inmunología , Macrófagos/metabolismo , Macrófagos/fisiología , Microglía/metabolismo , Receptor Cannabinoide CB2/biosíntesis , Receptor Cannabinoide CB2/inmunología , Receptor Cannabinoide CB2/metabolismo
13.
Bioresour Technol ; 99(11): 4935-42, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17964139

RESUMEN

This study was conducted under greenhouse conditions to evaluate the potential use of SPS as a fertilizer, amendment and/or liming agent for wheat (Triticum aestivum L.). Two representative Mediterranean agricultural soils, a Cambic Arenosol (cmAR) and a Cromic Cambisol (crCM) were used. Treatments included four sludge rates ranging from 0 to 40 g kg(-1) (equivalent of 0, 38, 88 and 120 Mg ha(-1)). A significant increment in soil pH, organic carbon, N total, available P and exchangeable K were observed in both soils. Sludge application significantly increased N and decreased Zn, Mn and Cu concentrations in wheat. Wheat grain yields were reduced by 33% and 37% when 120 Mg SPS ha(-1) was applied to cmAR and crCM soils, respectively, due apparently to unavailability of Mg. However, straw yields, with much lower Mg requirements, increased significantly with SPS rates. Secondary pulp mill sludge seems to be a potential source of organic matter, N, P, K and a potential soil amendment liming agent for acid soils, when appropriate supplemental fertilizer was provided. For grain crops grown in these soils, addition of Mg is required for proper nutrient balance.


Asunto(s)
Agricultura , Papel , Aguas del Alcantarillado , Suelo , Triticum/crecimiento & desarrollo , Carbono/metabolismo , Concentración de Iones de Hidrógeno , Intercambio Iónico , Región Mediterránea , Nitrógeno/metabolismo , Factores de Tiempo
14.
Bioresour Technol ; 99(17): 8294-8, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18406609

RESUMEN

A laboratory aerobic incubation study was performed during 18 weeks under controlled conditions to assess the effects of applying different doses of pulp mill inorganic wastes on the physical-chemical properties of an acid Dystric Cambissol. Three different inorganic wastes were tested - wood ash, dregs and grits, and an agriculture limestone was used as reference. Results showed that increasing the dose applied of the different inorganic wastes tested always led to significant raises of soil pH at different incubation times demonstrating that its use as alternative-liming materials could be a valid and less expensive option to the use of commercial agricultural limestone. Moreover, no immediate concerns seem to be expected related to soil exchangeable sodium (Na) content, at least for the doses needed to increase soil pH until the targeted value 6.5. Particularly for wood ash a pronounced increase on soil extractable potassium and phosphorous was observed, indicating that besides the liming effect this waste can contribute to improve soil fertility by supplying significant available amounts of these nutrients. Finally, metals do not seem to be a limiting factor for the application to land of these by-products.


Asunto(s)
Carbonato de Calcio/química , Residuos Industriales , Papel , Cationes , Elementos Químicos , Concentración de Iones de Hidrógeno , Metales Pesados/análisis , Suelo/análisis , Factores de Tiempo
15.
Mol Cell Biol ; 7(8): 2700-7, 1987 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3670290

RESUMEN

Eight strains of Chinese hamster ovary (CHO) cells having an assembly-defective beta-tubulin were found among revertants of strain Cmd 4, a mutant with a conditional lethal mutation in a beta-tubulin gene (F. Cabral, M. E. Sobel, and M. M. Gottesman, Cell 20:29-36, 1980). The altered beta-tubulins in these strains have electrophoretically silent alterations or, in some cases, an increase or a decrease in apparent molecular weight based on their migration in two-dimensional gels. The identity of these variant proteins as beta-tubulin was confirmed by peptide mapping, which also revealed the loss of distinct methionine-containing peptides in the assembly-defective beta-tubulins of lower apparent molecular weight. The altered mobility of these beta-tubulin polypeptides was not the result of a posttranslational modification, since the altered species could be labeled in very short incubations with [35S]methionine and were found among in vitro-translated polypeptides by using purified mRNA. In at least one strain, an altered DNA restriction fragment could be demonstrated, suggesting that an alteration occurred in one of the structural genes for beta-tubulin. Assembly-defective beta-tubulin was unstable and turned over with a half-life of only 1 to 2 h in exponentially growing cells. This rapid degradation of a tubulin gene product resulted in approximately 30% lower steady-state levels of both alpha- and beta-tubulin yet did not affect the growth rate of the cells or the distribution of the microtubules as judged by immunofluorescence microscopy. These results argue that CHO cells possess a beta-tubulin gene product that is not essential for survival.


Asunto(s)
Mutación , Tubulina (Proteína)/genética , Animales , Línea Celular , Clonación Molecular , Cricetinae , Cricetulus , ADN/metabolismo , Estabilidad de Medicamentos , Femenino , Cinética , Microtúbulos/metabolismo , Microtúbulos/ultraestructura , Ovario , Biosíntesis de Proteínas , ARN Mensajero/genética , Tubulina (Proteína)/metabolismo
16.
Mol Cell Biol ; 2(6): 720-9, 1982 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-14582168

RESUMEN

We recently described the isolation of a mutant Chinese hamster ovary cell (Cmd 4) resistant to the cytotoxic effects of colcemid (Cabral et al., Cell 20:29-36, 1980). This mutant carries an altered beta-tubulin but still grows normally at 37 degrees C. In the present study we found that Cmd 4 is temperature sensitive for growth at 40.3 degrees C. A class of revertants selected for temperature resistance had simultaneously lost colcemid resistance and the altered beta-tubulin. In addition, we isolated a temperature-resistant revertant which carries a further alteration in the mutant beta-tubulin polypeptide. This second alteration appears to make the mutant beta-tubulin incompetent to assemble into microtubules, resulting in a strain which is again colcemid sensitive. These revertant cell lines provide strong evidence that a mutation in beta-tubulin can confer both colcemid resistance and temperature sensitivity on a mammalian cell line. Cellular microtubules studied by indirect immunofluorescence in both mutant and revertant cell lines had an apparently normal distribution at permissive and nonpermissive temperatures, yet mitosis appears to be abnormal in the mutant cell line. We conclude from these studies that incorporation of the altered beta-tubulin into microtubules does not affect their distribution but may affect their function during mitosis.


Asunto(s)
Antineoplásicos/farmacología , Demecolcina/farmacología , Resistencia a Antineoplásicos/genética , Mutación/genética , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo , Animales , Células CHO , División Celular/efectos de los fármacos , Supervivencia Celular , Cricetinae , Electroforesis en Gel Bidimensional , Microtúbulos/efectos de los fármacos , Microtúbulos/metabolismo , Mapeo Peptídico , Temperatura
17.
Bioresour Technol ; 98(17): 3213-20, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16905314

RESUMEN

To study the possibility of some residues from pulp and paper industry being used as substrates to produce seedlings in containers, three composting experiments were carried out using eucalyptus bark, pine bark and a mixture (60:40, v:v) of pine bark+eucalyptus bark. Biochemical parameters studied were: acid and alkaline phosphatases, lipase (C10), protease, urease, beta-glucosidase and total cellulases. The microbiological populations of total aerobic bacteria, total fungi, actinomycetes, nitrifying bacteria, cellulolytic bacteria and fungi were also evaluated. At the end of the process physicochemical characterization of composts was also performed. Results showed in general that the highest microbiological populations as well as for enzymatic activities occurred during the thermophilic phase (>40 degrees C) of the process. On the other hand and according to the physicochemical characteristics of composts pine bark is the most appropriate material to be used in the formulation of substrates to produce plants in containers.


Asunto(s)
Eucalyptus , Pinus , Corteza de la Planta/metabolismo , Corteza de la Planta/microbiología , Eliminación de Residuos , Suelo , Bacterias/clasificación , Bacterias/metabolismo , Hongos/clasificación , Hongos/metabolismo , Residuos Industriales , Papel , Microbiología del Suelo
18.
Bioresour Technol ; 98(17): 3294-7, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16919933

RESUMEN

A composted material obtained from forestry wastes and solid phase of pig slurry was evaluated as a substrate component for the production of tomato and lettuce seedlings. Four different substrates were tested: compost (100C), a mixture of 75% compost and 25% peat substrate (75C), a mixture of 50% compost and 50% peat substrate (50C), and peat-based substrate (control). Compost increased the pH of the substrate from 6.3 (control) to 6.9 (100C) but did not affect the electrical conductivity (0.26 and 0.27 mScm(-1), respectively, for control and 100C). Germination and growth of lettuce seedlings were not affected by the substrate type, contrasting with tomato seedlings where the highest growth occurred at 100C substrate. Increasing compost percentage on substrate increased nitrogen, calcium and magnesium availability and, consequently, the concentration of these elements in plant tissues increased. On the contrary, potassium and manganese concentration decreased. Results from the study suggest that the compost studied is a good alternative to peat-based substrates for the production of vegetable seedlings.


Asunto(s)
Agricultura Forestal , Eliminación de Residuos , Plantones/crecimiento & desarrollo , Suelo , Porcinos , Animales , Lactuca/química , Lactuca/crecimiento & desarrollo , Solanum lycopersicum/química , Solanum lycopersicum/crecimiento & desarrollo , Plantones/química , Eliminación de Residuos Líquidos
19.
Interv Neuroradiol ; 23(6): 594-600, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28950737

RESUMEN

Purpose Hyper-attenuating lesions, or contrast staining, on a non-contrast brain computed tomography (NCCT) scan have been investigated as a predictor for hemorrhagic transformation after endovascular treatment of acute ischemic stroke (AIS). However, the association of hyper-attenuating lesions and final ischemic areas are poorly investigated in this setting. The aim of the present study was to assess correlations between hyper-attenuating lesions and final brain infarcted areas after thrombectomy for AIS. Methods Data from patients with AIS of the anterior circulation who underwent endovascular treatment were retrospectively assessed. Images of the brain NCCT scans were analyzed in the first hours and late after treatment. The hyper-attenuating areas were compared to the final ischemic areas using the Alberta Stroke Program Early CT Score (ASPECTS). Results Seventy-one of the 123 patients (65.13%) treated were included. The association between the hyper-attenuating region in the post-thrombectomy CT scan and final brain ischemic area were sensitivity (58.3% to 96.9%), specificity (42.9% to 95.6%), positive predictive values (71.4% to 97.7%), negative predictive values (53.8% to 79.5%), and accuracy values (68% to 91%). The highest sensitivity values were found for the lentiform (96.9%) and caudate nuclei (80.4%) and for the internal capsule (87.5%), and the lowest values were found for the M1 (58.3%) and M6 (66.7%) cortices. Conclusions Hyper-attenuating lesions on head NCCT scans performed after endovascular treatment of AIS may predict final brain infarcted areas. The prediction appears to be higher in the deep brain regions compared with the cortical regions.


Asunto(s)
Infarto Encefálico/diagnóstico por imagen , Infarto Encefálico/terapia , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/terapia , Angiografía Cerebral/métodos , Angiografía por Tomografía Computarizada/métodos , Procedimientos Endovasculares/métodos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/terapia , Trombectomía/métodos , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Sensibilidad y Especificidad , Resultado del Tratamiento
20.
J Leukoc Biol ; 78(6): 1192-7, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16204639

RESUMEN

Microglia, resident macrophages of the brain, function as immune effector and accessory cells. Paradoxically, they not only play a role in host defense and tissue repair but also have been implicated in a variety of neuropathological processes. Microglia, in addition to exhibiting phenotypic markers for macrophages, express CB1 and CB2 cannabinoid receptors. Recent studies suggest the existence of a third, yet-to-be cloned, non-CB1, non-CB2 cannabinoid receptor. These receptors appear to be functionally relevant within defined windows of microglial activation state and have been implicated as linked to cannabinoid modulation of chemokine and cytokine expression. The recognition that microglia express cannabinoid receptors and that their activation results in modulation of select cellular activities suggests that they may be amenable to therapeutic manipulation for ablating untoward inflammatory responses in the central nervous system.


Asunto(s)
Sistema Nervioso Central/inmunología , Sistema Nervioso Central/metabolismo , Sistema Inmunológico/inmunología , Microglía/inmunología , Microglía/metabolismo , Receptores de Cannabinoides/inmunología , Animales , Cannabinoides/metabolismo , Cannabinoides/farmacología , Sistema Nervioso Central/citología , Encefalitis/tratamiento farmacológico , Encefalitis/inmunología , Encefalitis/prevención & control , Gliosis/tratamiento farmacológico , Gliosis/inmunología , Gliosis/prevención & control , Humanos , Receptor Cannabinoide CB1/genética , Receptor Cannabinoide CB1/inmunología , Receptor Cannabinoide CB2/genética , Receptor Cannabinoide CB2/inmunología
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