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1.
Pancreatology ; 22(7): 1020-1027, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35961936

RESUMEN

BACKGROUND/OBJECTIVES: Pancreatic exocrine insufficiency (PEI) is a common complication following pancreatoduodenectomy (PD) leading to malnutrition. The course of PEI and related symptoms and vitamin deficiencies is unknown. This study aimed to assess the (long-term) incidence of PEI and vitamin deficiencies after PD. METHODS: A bi-centre prospective observational cohort study was performed, including patients who underwent PD for mainly pancreatic and periampullary (pre)malignancies (2014-2018). Two cohorts were formed to evaluate short and long-term results. Patients were followed for 18 months and clinical symptoms were evaluated by questionnaire. PEI was based on faecal elastase-1 (FE-1) levels and/or clinical symptoms. RESULTS: In total, 95 patients were included. After three months, all but three patients had developed PEI and 27/29 (93%) patients of whom stool samples were available showed abnormal FE-1 levels, which did not improve during follow-up. After six months, all patients had developed PEI. During follow-up, symptoms resolved in 35%-70% of patients. Vitamin D and K deficiencies were observed in 48%-79% of patients, depending on the moment of follow-up; 0%-50% of the patients with deficiencies received vitamin supplementation. DISCUSSION: This prospective study found a high incidence of PEI after PD with persisting symptoms in one-to two thirds of all patients. Limited attention was paid to vitamin deficiencies. Improved screening and treatment strategies for PEI and vitamins need to be designed.


Asunto(s)
Insuficiencia Pancreática Exocrina , Pancreaticoduodenectomía , Humanos , Pancreaticoduodenectomía/efectos adversos , Estudios Prospectivos , Insuficiencia Pancreática Exocrina/epidemiología , Insuficiencia Pancreática Exocrina/etiología , Insuficiencia Pancreática Exocrina/diagnóstico , Páncreas , Vitamina A
2.
Br J Surg ; 103(3): 257-66, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26785646

RESUMEN

BACKGROUND: Health-related quality of life (QoL) is of major importance in pancreatic cancer, owing to the limited life expectation. The aim of this prospective longitudinal study was to describe QoL in patients undergoing resection for pancreatic or periampullary malignancy. METHODS: QoL was measured on a scale of 0-100 in patients who underwent pancreatic resection for malignancy or premalignancy at the University Medical Centre Utrecht before resection, and 1, 3, 6 and 12 months after surgery. Measures consisted of the RAND-36, the European Organization for Research and Treatment of Cancer (EORTC) core questionnaire (QLQ-C30) and the EORTC pancreatic cancer-specific module (QLQ-PAN26). RESULTS: Between March 2012 and November 2013, 68 consecutive patients with a malignancy (59 patients) or premalignancy (9) were included. Physical role restriction, social and emotional domains showed a significant and clinically relevant deterioration directly after operation in 53 per cent (RAND-36, P < 0.001), 63 and 78 per cent (QLQ-C30 and RAND-36 respectively, P < 0.001) and 37 per cent (RAND-36, P < 0.001) of patients respectively. Most domains demonstrated recovery to preoperative values or better at 3 months, except for physical functioning. Emotional functioning at 3, 6 and 12 months was better than at baseline (P < 0.001). Symptom scores revealed a deterioration in vitality, pain (P = 0.002), fatigue (P < 0.001), appetite loss (P < 0.001), altered bowel habit (P = 0.001) and side-effects (P < 0.001) after 1 month. After 3 months, only side-effects were worse than preoperative values (P < 0.001). CONCLUSION: QoL after pancreatic resection for malignant and premalignant tumours decreased considerably in the early postoperative phase. Full recovery of QoL took up to 6 months after the operation.


Asunto(s)
Estado de Salud , Pancreatectomía/métodos , Neoplasias Pancreáticas/cirugía , Calidad de Vida , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pancreatectomía/psicología , Neoplasias Pancreáticas/psicología , Estudios Prospectivos , Encuestas y Cuestionarios
3.
Br J Cancer ; 110(5): 1179-88, 2014 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-24423923

RESUMEN

BACKGROUND: In experimental models of glioblastoma multiforme (GBM), irradiation (IR) induces local expression of the chemokine CXCL12/SDF-1, which promotes tumour recurrence. The role of CXCR7, the high-affinity receptor for CXCL12, in the tumour's response to IR has not been addressed. METHODS: We tested CXCR7 inhibitors for their effects on tumour growth and/or animal survival post IR in three rodent GBM models. We used immunohistochemistry to determine where CXCR7 protein is expressed in the tumours and in human GBM samples. We used neurosphere formation assays with human GBM xenografts to determine whether CXCR7 is required for cancer stem cell (CSC) activity in vitro. RESULTS: CXCR7 was detected on tumour cells and/or tumour-associated vasculature in the rodent models and in human GBM. In human GBM, CXCR7 expression increased with glioma grade and was spatially associated with CXCL12 and CXCL11/I-TAC. In the rodent GBM models, pharmacological inhibition of CXCR7 post IR caused tumour regression, blocked tumour recurrence, and/or substantially prolonged survival. CXCR7 expression levels on human GBM xenograft cells correlated with neurosphere-forming activity, and a CXCR7 inhibitor blocked sphere formation by sorted CSCs. CONCLUSIONS: These results indicate that CXCR7 inhibitors could block GBM tumour recurrence after IR, perhaps by interfering with CSCs.


Asunto(s)
Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/radioterapia , Glioblastoma/tratamiento farmacológico , Glioblastoma/radioterapia , Receptores CXCR/antagonistas & inhibidores , Animales , Neoplasias Encefálicas/patología , Quimiocina CXCL11/metabolismo , Quimiocina CXCL12/metabolismo , Glioblastoma/patología , Humanos , Ratones , Ratones Desnudos , Recurrencia Local de Neoplasia/metabolismo , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores CXCR/metabolismo
4.
Genet Mol Res ; 10(3): 2223-9, 2011 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-21968729

RESUMEN

We developed 12 microsatellite loci for the endangered minnow species, Tanichthys albonubes, using PCR-based isolation of microsatellite arrays. These new markers were tested in 26 individuals from a wild population collected from Guangzhou in China and 26 individuals from a cultured strain. The number of alleles ranged from two to nine and the expected heterozygosity from 0.177 to 0.853. The wild population had significantly higher allelic richness than the cultured strain, with a mean allelic richness of 5.52 (range = 3.69-8.64) and 3.13 (range = 1.99-5.73) for the wild population and the cultured strain, respectively. No evidence of a recent bottleneck was detected in the wild population, but it was found in the cultured strain based on the BOTTLENECK test. These primers can be used to understand the demography and to examine genetic differences between the cultured T. albonubes strains and wild populations to help determine conservation and reintroduction strategies.


Asunto(s)
Cyprinidae/genética , Repeticiones de Microsatélite , Alelos , Animales , Secuencia de Bases , Cartilla de ADN/genética , Especies en Peligro de Extinción , Marcadores Genéticos , Variación Genética , Técnica del ADN Polimorfo Amplificado Aleatorio , Análisis de Secuencia de ADN
5.
Br J Cancer ; 104(12): 1805-9, 2011 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-21587260

RESUMEN

Local recurrence of glioblastomas is a major cause of patient mortality after definitive treatment. This review discusses the roles of the chemokine stromal cell-derived factor-1 and its receptor CXC chemokine receptor 4 (CXCR4) in affecting the sensitivity of glioblastomas to irradiation. Blocking these molecules prevents or delays tumour recurrence after irradiation by inhibiting the recruitment of CD11b+ monocytes/macrophages that participate in revascularising the tumour. We review the literature pertaining to the mechanism by which revascularisation occurs following tumour irradiation using experimental models. Areas of interest and debate in the literature include the process by which endothelial cells die after irradiation and the identity/origin of the cells that reconstitute the tumour blood vessels after injury. Understanding the processes that mediate tumour revascularisation will guide the improvement of clinical strategies for preventing recurrence of glioblastoma after irradiation.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Quimiocina CXCL12/antagonistas & inhibidores , Glioblastoma/radioterapia , Neovascularización Patológica/prevención & control , Receptores CXCR4/antagonistas & inhibidores , Animales , Neoplasias Encefálicas/irrigación sanguínea , Antígeno CD11b/análisis , Quimiocina CXCL12/fisiología , Glioblastoma/irrigación sanguínea , Humanos , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia/prevención & control , Receptores CXCR4/fisiología
7.
Environ Technol ; 30(2): 161-72, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19278157

RESUMEN

The decolorization and transformation of the anthraquinone dye, Reactive Blue 19 (RB-19), by ozonation with a semi-batch reactor were investigated. The effects of different operating parameters, such as the initial RB-19 concentrations, ozone feed rates and initial pH, on the performance of color, dye and total organic carbon (TOC) removal were also evaluated based on their pseudo-first-order rate constants and removal efficiencies. The experimental results indicated that the removal of color and the dye itself was more rapid and complete than that of TOC in all the ozonation tests. However, increasing the initial RB-19 concentration had a significant effect on decreasing the rate constant of RB-19 reduction. In addition, increasing the ozone feed rate had positive effects on the color, dye and TOC removal, particularly on the TOC diminution. The rate constant and efficiency of color removal were highest at initial acidic pH conditions, but the dye and TOC removal were more effective at initial basic pH values, possibly due to the more powerful and non-selective hydroxyl radical oxidation.


Asunto(s)
Antraquinonas/química , Colorantes/química , Oxidantes Fotoquímicos/química , Ozono/química , Purificación del Agua/métodos , Color , Concentración de Iones de Hidrógeno , Cinética , Industria Textil , Contaminantes Químicos del Agua/química
8.
Environ Technol ; 28(8): 935-41, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17879852

RESUMEN

The textile industry is one of the major industries of Taiwan but unfortunately it produces toxic and low biodegradable wastewater. To remedy this problem, this study compared the performance of the membrane bioreactor (MBR) and sequencing batch reactor (SBR) processes for treating real textile dyeing wastewater. The microbial diversity of the MBR process was also identified by a combination of culturing methods and molecular biotechnology. The removal efficiencies of the MBR process for color, COD, BOD, and SS were 54, 79, 99, and 100%, respectively, all higher than the corresponding parameters for the SBR process: i.e., 51, 70, 96, and 60%. All the above four parameters for the MBR effluent meet the criteria of the Taiwan EPA, while on the other hand, for the SBR process, only color and COD meet the Taiwan EPA effluent criteria. Furthermore, the genus Microbacterium, in particular Microbacterium aurum, was the most predominant population, accounting for 70.6% of the total isolates, and might be responsible for the degradation of the dyeing wastewater. Another two textile dyeing degradation bacteria, Paenibacillus azoreducens and Bacillus sp., were also observed as predominant bacteria in MBR sludge.


Asunto(s)
Bacterias/aislamiento & purificación , Reactores Biológicos , Residuos Industriales , Industria Textil , Contaminantes Químicos del Agua/metabolismo , Bacterias/genética , Bacterias/metabolismo , Biodiversidad , Color , ADN Bacteriano/genética , Filogenia , ARN Ribosómico 16S/genética , Eliminación de Residuos Líquidos
9.
Environ Technol ; 27(6): 683-93, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16865924

RESUMEN

This study examined the factors that influence the reductive dechlorination of trichloroethylene (TCE) when direct current is externally supplied to a laboratory scale iron wall. Experimental results indicated that an anode electrode was placed in contact with the iron filling near the inlet of the column, and then a cathode was located on the top of the column. Excellent TCE degradation efficiency was displayed. The surface of the iron particles was acid-washed by H+, owing to water oxidation around the anode, and large quantities of Fe2+ were produced as a reductant which enhanced the TCE degradation, due to iron corrosion caused by the supply of external electrons. The cathode should be placed in sand fill atop the iron filling in order to avoid the formation of iron (hydr) oxide precipitates on the surface of the iron particles when the pH increases as a result of the release of OH+ around the cathode. Due to more H+ being released, which benefited the acid-washing of the iron filling, the TCE removal efficiency increased from 32% to 100% when the electric potential increased to 60V. However, black precipitates of iron (hydr) oxide were observed coated on the iron surface, causing the blocking of pores in the iron wall with the increase in the electric potential application. The efficiency of TCE degradation was almost equal regardless of groundwater velocity when direct current was applied to the iron wall. Based on observations of TCE degradation during long-term operations, the TCE removal efficiency in the effluent reached 100% after seven days of operation and maintained this high level after 25 days of operation. Thus, iron wall by electroremediation displayed excellent potential for development in long-term operations.


Asunto(s)
Cloro/aislamiento & purificación , Electrólisis , Hierro/química , Tricloroetileno/aislamiento & purificación , Purificación del Agua/métodos , Biodegradación Ambiental , Cloro/química , Electroquímica , Electrodos , Electrólitos , Compuestos Férricos/química , Concentración de Iones de Hidrógeno , Oxidación-Reducción , Factores de Tiempo , Tricloroetileno/química , Abastecimiento de Agua
10.
Environ Technol ; 25(2): 201-10, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15116878

RESUMEN

The biotransformation of octylphenol polyethoxylate surfactant (Triton X-100) and bacterial communities in soil microcosms was investigated. The soil microcosms were designed to simulate real sites of bioremediation. The soil used in this study was contaminated with pesticides and alkylphenol polyethoxylate surfactants over a long period of time. The nitrogen source, (NH4)2SO4 and the mineral salt basal solution were added to the microcosm and the water content was adjusted to 50% with distilled water. The microcosms were aerated using an aeration system with an air flow rate of 0.3 l min(-1). The exogenous bacterial strain Pseudomonas sp. SH4 was added to the microcosms to increase the rate of biotransformation of the Triton X-100. The number of microorganisms and the theoretical extent of formation of carbon dioxide were estimated to evaluate the biotransformation of Triton X-100 in the microcosms. The analytical results revealed that the exogenous bacteria could increase the rate of transformation of Triton X-100 by approximately 50%. Aeration of the microcosm increased the biotransformation of Triton X-100 by 45%. Bacterial count of 6.8x10(10) MPN g(-1) of soil was achieved in the M5 microcosm. Analysis of the bacterial community by 16S rDNA sequences revealed that Pseudomonas sp. SH4 could dominate all the microcosms to which it was added as an exogenous bacteria. The quantity of the indigenous bacterial strains Stenotrophomonas maltophilia, Stenotrophomonas sp. and clone 4-70 were also enhanced in the microcosms by the aeration, and the addition of carbon and nitrogen source.


Asunto(s)
Bacterias Aerobias/fisiología , Octoxinol/metabolismo , Plaguicidas/metabolismo , Contaminantes del Suelo/metabolismo , Tensoactivos/metabolismo , Biodegradación Ambiental , Pseudomonas/fisiología , Microbiología del Suelo
11.
J Gen Intern Med ; 16(8): 563-8, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11556935

RESUMEN

OBJECTIVE: To perform a meta-analysis on existing randomized controlled trials to investigate the efficacy of patient letter reminders on increasing cervical cancer screening using Pap smears. METHODS: A search was conducted for all relevant published and unpublished studies between the years 1966 and 2000. Eligibility criteria included randomized controlled studies that examined populations due for Pap smear screening. The intervention studied was in the form of a reminder letter. The Mantel-Haenszel method was used to measure the summary effect of the intervention. A test for homogeneity using the Mantel-Haenszel method was performed. RESULTS: Ten articles fulfilled the inclusion criteria, including one unpublished study. The test for homogeneity showed evidence of heterogeneity (chi2 = 31, 9 df, P <.001). An analysis for causes of heterogeneity was pursued. Division into subpopulations based on socioeconomic status resolved the heterogeneity (chi2 = 5.2, 8 df, P =.75). The studies evaluating those in lower socioeconomic groups had a smaller response (odds ratio [OR], 1.16; 95% confidence interval [CI], 0.99 to 1.35) than those studies using mixed populations (OR, 2.02; 95% CI, 1.79 to 2.28). The pooled odds ratio showed that patients who received the intervention were significantly more likely to return for screening than those who did not (OR, 1.64; 95% CI, 1.49 to 1.80). CONCLUSIONS: Patient reminders in the form of mailed letters increase the rate of cervical cancer screening. Patient letter reminders have less efficacy in lower socioeconomic groups.


Asunto(s)
Tamizaje Masivo , Prueba de Papanicolaou , Sistemas Recordatorios , Neoplasias del Cuello Uterino/diagnóstico , Frotis Vaginal , Adolescente , Adulto , Anciano , Distribución de Chi-Cuadrado , Femenino , Humanos , Persona de Mediana Edad , Oportunidad Relativa , Factores Socioeconómicos
12.
Artículo en Inglés | MEDLINE | ID: mdl-11440876

RESUMEN

The site of yolk protein synthesis in crustaceans has long been a subject of controversy. The vitellogenin gene structure was partially reported only very recently in Macrobrachium rosenbergii, after which the hepatopancreas was confirmed as the extraovarian site of vitellogenin synthesis in that species. Ovaries are the most frequently reported as the site of yolk protein synthesis in penaeid shrimp. Using cDNA reversed-transcribed from mRNA isolated from the hepatopancreas of vitellogenic female shrimp, Penaeus monodon, we found that its deduced amino acid sequence had high identity of 48% with that from M. rosenbergii vitellogenin. A similar location of the intron in the sequenced region of genomic DNA was also found between these two species. We therefore concluded that the hepatopancreas the extraovarian site of vitellogenin synthesis in P. monodon in vivo. The partial structure of vitellogenin gene is presented in this study.


Asunto(s)
Sistema Digestivo/metabolismo , Penaeidae/metabolismo , Vitelogeninas/biosíntesis , Secuencia de Aminoácidos , Animales , Secuencia de Bases , ADN Complementario , Femenino , Datos de Secuencia Molecular , Ovario/metabolismo , Penaeidae/genética , Reacción en Cadena de la Polimerasa , ARN Mensajero/genética , ARN Mensajero/metabolismo , Alineación de Secuencia , Vitelogeninas/química , Vitelogeninas/genética
13.
WMJ ; 100(2): 39-42, 38, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11419369

RESUMEN

Falls, poisoning, drowning, and burns comprise the four most common causes of unintentional injury death not related to motor vehicles. We examine mortality trends for these causes of injury in Wisconsin over a 10-year period (1986-1996). While national age-adjusted rates for fall mortality have remained relatively stable, Wisconsin has experienced a sharp 38% increase. The greatest increase in fall mortality was seen in the aged. Nationally, poisoning mortality rose by approximately 50% during this same period while Wisconsin saw almost no increase in mortality (3%) from poisoning. Wisconsin did experience an increase in deaths from poisoning in middle-aged adults. Mortality from drowning decreased by about 28% both in Wisconsin and in the United States, with much of the progress occurring in children and young adults. Burn mortality also declined nationally and within Wisconsin by 30% to 35%. The Wisconsin Public Health Department's "Healthier People in Wisconsin" objectives for the year 2000 will likely be met for drowning and burns, but not for falls. Overall, unintentional injury mortality in Wisconsin is decreasing. However, specific subpopulations are not reaping the benefits of this decline, suggesting a possible focus for future efforts aimed at lowering unintentional injury mortality.


Asunto(s)
Accidentes por Caídas/estadística & datos numéricos , Quemaduras/epidemiología , Ahogamiento/epidemiología , Intoxicación/epidemiología , Heridas y Lesiones/epidemiología , Accidentes por Caídas/mortalidad , Accidentes por Caídas/prevención & control , Adolescente , Adulto , Distribución por Edad , Anciano , Quemaduras/etiología , Quemaduras/prevención & control , Causas de Muerte , Centers for Disease Control and Prevention, U.S. , Niño , Preescolar , Ahogamiento/etiología , Ahogamiento/prevención & control , Femenino , Prioridades en Salud , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Intoxicación/etiología , Intoxicación/prevención & control , Vigilancia de la Población , Factores de Riesgo , Distribución por Sexo , Estados Unidos/epidemiología , Wisconsin/epidemiología , Heridas y Lesiones/etiología , Heridas y Lesiones/prevención & control
14.
Environ Technol ; 22(1): 39-46, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11286054

RESUMEN

A novel fibrous-bed trickling filter was developed to remove toluene present in contaminated air. Pure culture of Pseudomonas putida F1 was attached on fibrous-bed and utilized toluene as the carbon source. Experimental results indicated the removal efficiency decreased with the increase of inlet concentration. In general, the removal efficiency of toluene was greater than 90% when the inlet loading capacity was below 70 g m-3h-3. The elimination capacity increased with increasing inlet loading capacity, but the increased rate decreased gradually. When the inlet loading capacity increased to 300 g m-3h-1, the elimination capacity could approach to 130 g m-3h-1. The first order kinetics model was useful to describe the removal of toluene in this filter and an excellent linear relationship was found between the apparent first order parameter and inlet concentration (ranging from 1.2 g m-3 to 3.5 g m-3). Also, the performance of fibrous-bed trickling filter was relatively stable during the four-month period of continuous operation. Slight clogging phenomena of filters were observed only under high loading capacity.


Asunto(s)
Contaminantes Atmosféricos/química , Contaminación del Aire/prevención & control , Filtración/instrumentación , Tolueno/química , Fenómenos Químicos , Química Física , Matemática , Microscopía Electrónica de Rastreo , Modelos Químicos , Pseudomonas putida
15.
Water Sci Technol ; 44(10): 261-7, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11794663

RESUMEN

This study investigated the characteristics of SSA in Taiwan area. The potential applications of SSA reuse were also evaluated. Four major characteristics of SSA, including chemical compositions, pozzolanic properties, physical properties, and surface properties were analyzed. Experimental results found that SSA was a complex mixture of burnt residues of sludge biomass and minerals. The major chemical compositions of SSA were silicon oxide, aluminium oxide, and iron oxide. The most predominant silicon oxide occupied 41.3 to 56.1% of overall SSA weight and approximately 60% weight of silicon oxide in SSA was amorphous type. Due to the effect of amorphous silicon oxide, the SSA exerted pozzolanic activity. The strength activity index (SAI) value of SSA was between 53.6 and 74.3%. The SSA particles were also the agglomeration of finer grains between 0.1 and 1 microm of size. Therefore the SSA was porous with irregular particles with significant pore surface area. Additionally, the SSA exerted negative surface charge and cation-exchange capacity in neutral aqueous phase. Based on the SSA characteristics found in this study, four potential applications of SSA reuse were evaluated. These technologies included reusing as fine aggregate, reusing as pozzolanic material, melting or vitrification treatment, and reusing as adsorbent. In addition, the advantages and disadvantages of the above potential applications of SSA were discussed.


Asunto(s)
Eliminación de Residuos/métodos , Aguas del Alcantarillado/química , Adsorción , Biomasa , Técnicas de Química Analítica , Conservación de los Recursos Naturales , Incineración
16.
J Immunol ; 164(5): 2660-6, 2000 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-10679106

RESUMEN

Lipoxins are a novel class of endogenous eicosanoid mediators that potently inhibit inflammatory events by signaling via specific receptors expressed on phagocytic cells. Animal models have shown that lipoxin A4 (LXA4) down-regulates inflammation in vivo. Here we demonstrate, for the first time, the expression of LXA4 receptors, and their up-regulation by IL-1 beta, in normal human synovial fibroblasts (SF). We examined whether exogenous LXA4 abrogated IL-1 beta stimulation of SF in vitro. IL-1 beta induced the synthesis of IL-6, IL-8, and matrix metalloproteinases (MMP)-1 and -3. At nanomolar concentrations, LXA4 inhibited these IL-1 beta responses with reduction of IL-6 and IL-8 synthesis, by 45 +/- 7% and 75 +/- 11%, respectively, and prevented IL-1 beta-induced MMP-3 synthesis without significantly affecting MMP-1 levels. Furthermore, LXA4 induced a 2-fold increase of tissue inhibitor of metalloproteinase (TIMP)-1 and a approximately 3-fold increase of TIMP-2 protein levels. LXA4 inhibitory responses were dose dependent and were abrogated by pretreatment with LXA4 receptor antiserum. LXA4-induced changes of IL-6 and TIMP were accompanied by parallel changes in mRNA levels. These results indicate that LXA4 in activated SF inhibits the synthesis of inflammatory cytokines and MMP and stimulates TIMP production in vitro. These findings suggest that LXA4 may be involved in a negative feedback loop opposing inflammatory cytokine-induced activation of SF.


Asunto(s)
Fibroblastos/inmunología , Ácidos Hidroxieicosatetraenoicos/fisiología , Interleucina-1/fisiología , Interleucina-6/antagonistas & inhibidores , Interleucina-8/antagonistas & inhibidores , Lipoxinas , Inhibidores de la Metaloproteinasa de la Matriz , Receptores de Formil Péptido , Receptores de Lipoxina , Membrana Sinovial/inmunología , Inhibidores Tisulares de Metaloproteinasas/biosíntesis , Células Cultivadas , Fibroblastos/enzimología , Fibroblastos/metabolismo , Humanos , Ácidos Hidroxieicosatetraenoicos/metabolismo , Inmunosupresores/metabolismo , Inmunosupresores/farmacología , Interleucina-6/biosíntesis , Interleucina-6/genética , Interleucina-8/biosíntesis , Metaloproteinasa 3 de la Matriz/biosíntesis , ARN Mensajero/metabolismo , Receptores de Superficie Celular/biosíntesis , Membrana Sinovial/enzimología , Membrana Sinovial/metabolismo , Inhibidores Tisulares de Metaloproteinasas/agonistas , Inhibidores Tisulares de Metaloproteinasas/genética , Regulación hacia Arriba/inmunología
17.
Mol Reprod Dev ; 54(3): 215-22, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10497343

RESUMEN

Vitellogenesis is an important part of reproductive process in crustaceans, and the process is characterized by the synthesis and accumulation of yolk protein in the developing oocytes. The yolk proteins in crustaceans mainly consist of vitellogenin (Vg) and vitellin (Vn), which are respectively present in extra-oocyte tissues and intra-oocytes. The site and the process of yolk protein synthesis in crustaceans are still controversial. The synthesis site of Vg in a crustacean species, Macrobrachium rosenbergii, is determined by immunological and immunohistochemical techniques, and molecular cloning of a cDNA encoding the primary structure of Vn in this study. The hepatopancrease is clearly shown to be the synthesis site of Vg in this species. The length of Vg mRNA was estimated as about 6 kb from Northern blotting analysis. The partial primary structure of Vg gene is presented, and the post-translational processing are further discussed. For the first time, the partial primary structure of Vg gene and the synthesis site of Vg approached by molecular cloning in crustaceans are presented.


Asunto(s)
ADN Complementario/análisis , Palaemonidae/genética , Vitelogeninas/biosíntesis , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Northern Blotting , Sistema Digestivo/metabolismo , Proteínas del Huevo/genética , Femenino , Inmunohistoquímica , Masculino , Datos de Secuencia Molecular , Palaemonidae/anatomía & histología , Pruebas de Precipitina , ARN Mensajero/análisis , Vitelogeninas/análisis , Vitelogeninas/metabolismo
18.
Circ Res ; 84(4): 378-83, 1999 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-10066671

RESUMEN

Endovascular stents expand the arterial lumen more than balloon angioplasty and reduce rates of restenosis after coronary angioplasty in selected patients. Understanding the factors involved in vascular injury imposed during stent deployment may allow optimization of stent design and stent-placement protocols so as to limit vascular injury and perhaps reduce restenosis. Addressing the hypothesis that a previously undescribed mechanism of vascular injury during stent deployment is balloon-artery interaction, we have used finite element analysis to model how balloon-artery contact stress and area depend on stent-strut geometry, balloon compliance, and inflation pressure. We also examined superficial injury during deployment of stents of varied design in vivo and in a phantom model ex vivo to show that balloon-induced damage can be modulated by altering stent design. Our results show that higher inflation pressures, wider stent-strut openings, and more compliant balloon materials cause markedly larger surface-contact areas and contact stresses between stent struts. Appreciating that the contact stress and contact area are functions of placement pressure, stent geometry, and balloon compliance may help direct development of novel stent designs and stent-deployment protocols so as to minimize vascular injury during stenting and perhaps to optimize long-term outcomes.


Asunto(s)
Arterias/patología , Cateterismo/efectos adversos , Stents/efectos adversos , Animales , Arterias/fisiopatología , Adaptabilidad , Endotelio Vascular/patología , Diseño de Equipo , Análisis de Elementos Finitos , Inflación Económica , Presión , Conejos
19.
J Biomed Mater Res ; 42(2): 188-98, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9773815

RESUMEN

We sought to examine whether surface modification of expanded polytetrafluoroethylene (ePTFE) vascular grafts might extend graft patency without modifying the graft structure. Amide and amine plasma (butylamine) were applied to graft surfaces using radio frequency glow discharge. Surface analyses by Fourier transform infrared spectroscopy-attenuated total reflectance, X-ray photoelectron spectroscopy, and dynamic contact angle measurements revealed the presence of nitrogen-containing functional groups on the plasma modified graft surfaces, along with an increased surface hydrophilicity. Bovine aortic endothelial cells were seeded on amide and amine plasma coated ePTFE vascular grafts and placed inside an artificial circulatory system under well-defined flow conditions. The seeded endothelial cells were exposed to either constant or pulsatile flow condition for 5 days. Their corresponding maximum wall shear stresses were 1 dyn/cm2 under constant flow and 65, 108, and 259 dyn/cm2 under various pulsatile flows. Plasma modified ePTFE vascular grafts enhanced the endothelial cell lining under constant and pulsatile flow conditions. Fluorescence nuclear staining, scanning electron microscopy, and histological staining indicated the formation of an endothelial cell monolayer on the plasma coated graft surfaces.


Asunto(s)
Amidas , Materiales Biocompatibles , Bioprótesis , Vasos Sanguíneos , Politetrafluoroetileno , Animales , Bovinos , Endotelio Vascular , Circulación Extracorporea/instrumentación , Circulación Extracorporea/métodos
20.
Chemosphere ; 37(6): 1045-61, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9722968

RESUMEN

Synthetic organic polymers used to purify drinking water are severely limited in that their impurities and by-products harm human health. In this study, the undesired effects resulted from chlorination and the enhanced attenuation of toxic organic compounds in drinking water from using synthetic organic polymer coagulants were investigated. In the simulated drinking water purification processes, synthetic organic polymers were used as coagulant aids, reacted with a disinfectant(chlorine) and formed a large number of volatile organic compounds (VOCs). Chloroform and benzene which, are carcinogenic compounds, had the maximum formation potential. Experimental results indicated that the total formation potential of these disinfection by-products significantly increased in the presence of turbidity. On the other hand, adding organic polymers to the coagulation systems resulted in more extensive remove of toxic organic compounds and turbidity. In coagulation and flocculation processes, the formation of clay/polymer complexes can facilitate the removal of toxic organic compounds in contaminated water.


Asunto(s)
Polímeros/química , Purificación del Agua , Abastecimiento de Agua/análisis , Silicatos de Aluminio , Fenómenos Químicos , Química Física , Arcilla , Desinfectantes/química , Nefelometría y Turbidimetría , Contaminantes Químicos del Agua/análisis
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