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1.
Ann Rheum Dis ; 69(1): 70-81, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19174392

RESUMEN

OBJECTIVES: To assess whether smoking is a risk factor for developing rheumatoid arthritis (RA). DESIGN: Meta-analysis. DATA SOURCES: were observational studies that examined the association between smoking history and the risk of developing RA identified through Medline and EMBASE (from 1966 to December 2006), relevant books and a reference search. Two authors independently extracted the following: authors' names, publication year, sample size, participant characteristics, odds ratios (OR) or relative risks, adjustment factors, study design and area where the study was conducted. Data syntheses were based upon random effects model. Summarised syntheses effects were expressed by OR. RESULTS: Sixteen studies were selected from among 433 articles. For men, summary OR for ever, current and past smokers were 1.89 (95% CI 1.56 to 2.28), 1.87 (1.49 to 2.34) and 1.76 (1.33 to 2.31), respectively. For rheumatoid factor-positive (RF+) RA, summary OR for ever, current and past smokers were 3.02 (2.35 to 3.88), 3.91 (2.78 to 5.50) and 2.46 (1.74 to 3.47), respectively. Summary OR for 20 or more pack-years of smoking was 2.31 (1.55 to 3.41). For women, summary OR for ever, current and past smokers were 1.27 (1.12 to 1.44), 1.31 (1.12 to 1.54) and 1.22 (1.06 to 1.40), respectively. For RF+ RA, summary OR for ever, current and past smokers were 1.34 (0.99 to 1.80), 1.29 (0.94 to 1.77) and 1.21 (0.83 to 1.77). Summary OR for 20 or more pack-years of smoking was 1.75 (1.52 to 2.02). CONCLUSION: Smoking is a risk factor for RA, especially RF+ RA men and heavy smokers.


Asunto(s)
Artritis Reumatoide/etiología , Fumar/efectos adversos , Adulto , Artritis Reumatoide/sangre , Artritis Reumatoide/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sesgo de Publicación , Proyectos de Investigación , Factor Reumatoide/sangre , Factores de Riesgo , Factores Sexuales , Fumar/epidemiología
2.
Diabetol Int ; 7(3): 252-258, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30603271

RESUMEN

BACKGROUND: The utility of casual serum triglyceride (TG) as a predictor of type 2 diabetes mellitus (DM) is unclear, especially during the most productive years. METHODS: Participants were 3271 workers (913 men and 2358 women, age 20-57) without DM at baseline. They underwent consecutive annual medical check-ups for 8 years. The association between newly diagnosed DM and casual serum TG level was determined by classifying the participants into 4 groups according to casual serum TG level at baseline: below 50 mg/dL (group A), 50-100 mg/dL (group B), 100-150 mg/dL (group C), and ≥150 mg/dL (group D). The effects of casual serum TG level in combination with sex, obesity, or serum glucose level on newly diagnosed DM were also evaluated. RESULTS: A total of 222 newly diagnosed type 2 DM cases with a mean age of 50 years old were observed during the follow-up period, i.e., 10/406 in group A, 66/1534 in group B, 58/712 in group C, and 88/619 in group D. Compared with group A, the odds ratio (ORs) for newly diagnosed DM (after adjusting for DM-associated factors) was found to increase with casual serum TG level: 1.38 (group B), 1.79 (group C), and 2.36 (group D). Moreover, the OR for newly diagnosed DM was higher in participants with high casual serum TG levels who were also male (OR 2.46), obese (OR 4.18), or had a high serum glucose level (OR 6.96) than in the reference group. CONCLUSIONS: Serum TG level ≥150 mg/dL when fasting or nonfasting is a significant predictor of type 2 diabetes in middle-aged Japanese workers.

3.
J Nutr Health Aging ; 19(7): 719-28, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26193854

RESUMEN

BACKGROUND/OBJECTIVES: Serum polyunsaturated fatty acid (PUFA) composition reflects dietary intake and is related to risks for cardiovascular diseases. We hypothesized that serum n-3 PUFA composition, especially including long-chain n-3 PUFA such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), is associated with inflammatory status, which is related to increased risk for cardiovascular diseases. SUBJECTS/METHODS: We investigated the relationship between serum PUFA composition and high-sensitivity C-reactive protein (hs-CRP) levels in a cross-sectional study among 1,102 healthy men and women aged 40-74 years who reside in Kobe City. Multiple linear regression models that predict hs-CRP level were prepared to confirm the contribution of serum total n-3 PUFA, long-chain n-3 PUFA, EPA and DHA compositions after adjusting for other PUFAs and atherosclerotic risk factors. RESULTS: The serum n-3 PUFA, particularly long-chain n-3 PUFA, compositions were inversely associated with the hs-CRP levels. The standardized regression coefficient was -0.089 (p < 0.01) for total n-3 PUFA, -0.091 (p < 0.01) for long-chain n-3 PUFA, -0.071 (p = 0.03) for EPA, and -0.068 (p = 0.04) for DHA. The n-6 PUFA compositions were also inversely associated with the hs-CRP levels (-0.169 [p < 0.01] for total n-6 PUFA and -0.159 [p < 0.01] for linoleic acid). CONCLUSIONS: The serum n-3 PUFA compositions were inversely related with the hs-CRP levels, similar associations were also observed in n-6 PUFA compositions. Our results suggest that dietary PUFA intake was inversely associated with attenuated inflammation in healthy Japanese population.


Asunto(s)
Pueblo Asiatico , Proteína C-Reactiva/análisis , Ácidos Grasos Omega-3/sangre , Ácidos Grasos Omega-6/sangre , Salud , Adulto , Anciano , Enfermedades Cardiovasculares/sangre , Ciudades , Estudios Transversales , Dieta , Ácidos Docosahexaenoicos/sangre , Ácido Eicosapentaenoico/sangre , Ácidos Grasos Omega-3/química , Femenino , Encuestas Epidemiológicas , Humanos , Inflamación/sangre , Japón , Masculino , Persona de Mediana Edad , Factores de Riesgo
4.
Phys Rev E Stat Nonlin Soft Matter Phys ; 63(4 Pt 2): 046408, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11308957

RESUMEN

It is shown by using a two-dimensional, fully relativistic, electromagnetic particle-in-cell simulation code that a force-free magnetic configuration in collisionless, electron-positron (pair) plasmas becomes unstable against current-driven Buneman instability and subsequently there occurs a strong magnetic field energy dissipation associated with collisionless magnetic reconnection, which can be driven by particle trapping due to two-dimensional electric potentials remaining in the nonlinear stage of the initial current-driven Buneman instability. About 43% of the initial magnetic field energy dissipates and is transformed to plasma heating as well as high-energy particle production. The energy spectrum in the high-energy region is given by an exponential type with two temperatures. We also show the simulation results for the electron-ion plasma to compare the effect of the mass ratio of the electron and proton.

5.
J Contam Hydrol ; 61(1-4): 3-16, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12598090

RESUMEN

The possibility of colloid generation from cement hydrates in a cementitious repository environment has been investigated through leaching experiments. Pulverized samples of High Flyash and Silica fume-content Cement (HFSC) and 1:9 ordinary portland cement/blast furnace slag (1:9 OPC/BFS) hydrate were leached in low-salinity groundwater at three solid-to-liquid (S/L) mass ratios (1:5, 1:50 and 1:100), and two temperatures (20 and 60 degrees C) for durations of nearly 2 and 8 months. Detailed characterization of colloid populations has been undertaken by TEM coupled with X-ray analysis. In addition, the surface charge and stability behavior of colloids have been investigated. The colloid concentrations in HFSC hydrate leachates generated at 20 and 60 degrees C show similar trends with S/L ratio. The colloid concentrations of leachates with the lower S/L ratio (1:50 and 1:100) are in the range of 10(11)-10(12) particles per liter. The majority of these particles are composed predominantly of Si, Ca, and Al; the mean particle size is less than 100 nm. The lowest colloid concentrations are found in the leachates with the highest S/L ratios, and the colloid populations tend to be dominated by larger particles. HFSC-derived colloid stability is due to a high negative zeta potential at alkaline pH values, combined with a calcium concentration that is below the critical coagulation concentration (CCC) for the colloids. A preliminary interpretation of HFSC-derived colloid stability based on classical DLVO theory provides a semi-quantitative explanation of the dependence of colloid populations on the S/L ratio in the leaching experiments.


Asunto(s)
Coloides/química , Materiales de Construcción , Concentración de Iones de Hidrógeno , Tamaño de la Partícula , Contaminantes del Suelo/análisis , Agua , Contaminantes del Agua/análisis
6.
Eye (Lond) ; 24(6): 1024-7, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19893590

RESUMEN

PURPOSE: In this study, the effects of maternal smoking along with other clinical risk factors in developing severe retinopathy of prematurity (ROP) were evaluated. DESIGN: A case-control study. METHODS: Records of newborn infants with an estimated postmenstrual age of 32 weeks or less (n=86) were reviewed. ROP grading was evaluated in accordance with the International Classification of Retinopathy of Prematurity. Severe ROP was diagnosed when it progressed to stage 3 with plus disease. The factors were first evaluated using a univariate logistic regression analysis between the groups of severe and non-severe ROP, followed by a multivariate logistic regression analysis using STATA version 10 and R version 2.71. RESULTS: A low birth weight, a long duration of artificial ventilation and oxygen supplementation, presence of chronic lung disease, and absence of maternal smoking were found to be significantly associated with severe ROP in the univariate logistic regression analysis. In the multivariate logistic regression analysis, maternal smoking was revealed as a significant factor independently associated with the incidence of severe ROP. CONCLUSIONS: An inhibitory effect of maternal smoking against developing severe ROP is suggested. The mechanism by which smoking may reduce the incidence of severe ROP needs to be further investigated.


Asunto(s)
Retinopatía de la Prematuridad/prevención & control , Fumar , Peso al Nacer , Estudios de Casos y Controles , Femenino , Humanos , Incidencia , Recién Nacido , Recien Nacido Prematuro , Modelos Logísticos , Enfermedades Pulmonares/epidemiología , Masculino , Terapia por Inhalación de Oxígeno , Respiración Artificial , Retinopatía de la Prematuridad/epidemiología , Retinopatía de la Prematuridad/etiología , Factores de Riesgo , Fumar/efectos adversos
9.
Prilozi ; 30(2): 71-80, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20087250

RESUMEN

Zebrafish kidney marrow (ZKM), which is equivalent to the haematopoietic bone marrow of mammals, produces all major blood cell types, which morphologically resemble their mammalian counterparts. To be able to exploit the advantages of zebrafish genetics for analysis of the general mechanisms controlling self-renewal, proliferation and lineage decisions of vertebrate haematopoetic cell populations, it is essential to develop a simple surgical technique in order to identify, dissect and take out the ZKM without contamination with other surrounding tissues and cells. However, the size of adult zebrafish is small (average size: 2.5 cm) and the ZKM is an extremely protected organ and not easy to localize, which makes this procedure a great microsurgical challenge. Here we report a new microsurgical technique to identify, localize and dissect ZKM in adult zebrafish using a new approach. The potential advantages of this technique are summarized here: it allows purity of the sample, which is critical for performing flow cytometry analysis and/or cell number count; it enables visualization of the ZKM without a parenchimal incision, which simplifies the further dissection; the learning curve is short, requiring only basic microsurgical skills, and it is reliable and highly reproducible. To further characterize the kidney marrow cells obtained by this technique, we performed histology, flow cytometry, cytospin experiments and cell counts.


Asunto(s)
Disección/métodos , Riñón/citología , Pez Cebra , Animales , Separación Celular , Citometría de Flujo , Células Madre Hematopoyéticas/citología , Masculino
10.
Clin Orthop Relat Res ; (254): 105-10, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-2323126

RESUMEN

A retrospective study involving 2027 patients with a limited range of motion of the shoulder in the period from 1970 to 1987 is described. Of these, 1219 patients (60%) were diagnosed as having frozen shoulder, with the highest incidence occurring in patients aged 50-60 years. The mechanism involved in the contracture is complicated. At first, the movement of the greater tuberosity at the subacromial level (also called the subacromial secondary joint) is limited due to bursitis. The external rotation of the upper arm then decreases, and the long rotator muscles contract. The relationship between the cause of contracture and the direction of the decreased mobility was analyzed. A ratio of the degree of external rotation with the arm beside the body to that achieved with the arm elevated to the horizontal plane showed values of almost one to one. Conservative treatment including physiotherapy, local anesthetic block, and joint distension must be attempted in all patients. If the conservative treatment remains ineffective, the surgical procedure should be considered. Satisfactory clinical results of arthroplasty of the subacromial joint were obtained in patients with frozen shoulder.


Asunto(s)
Contractura/epidemiología , Articulación del Hombro , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Contractura/fisiopatología , Femenino , Fracturas Óseas/epidemiología , Humanos , Luxaciones Articulares/epidemiología , Masculino , Persona de Mediana Edad , Movimiento , Enfermedades Musculares/epidemiología , Estudios Retrospectivos , Rotura Espontánea , Lesiones del Hombro , Articulación del Hombro/fisiopatología , Tendinopatía/epidemiología
11.
J Am Optom Assoc ; 64(8): 568-82, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8409195

RESUMEN

BACKGROUND: The influence of systemic disease, vascular abnormalities, hematologic and rheologic factors, pulsatile ocular blood flow, perfusion pressure, autoregulation, optic disc hemorrhage and the results of optic nervehead fluorescein angiographic studies are reviewed in the context of supporting evidence for the vasogenic theory of glaucoma. METHODS: Two case reports of patients with confirmed carotid artery occlusive disease and one case report of a patient with a history of hypovolemic blood loss are presented. RESULTS: These cases illustrate the importance of hypotensive crisis, perfusion pressure, collateral blood flow and the optic nerve head vascular autoregulatory mechanism in the pathogenesis of glaucoma and the differential diagnosis of pseudoglaucoma. CONCLUSIONS: Evaluation and consideration of both mechanical and vasogenic causes of the glaucomas is essential in the management of the glaucomas. It is also necessary to differential diagnose the "pseudo-glaucomas," and to manage them correctly.


Asunto(s)
Glaucoma de Ángulo Abierto/etiología , Anciano , Arteria Carótida Interna , Estenosis Carotídea/complicaciones , Enfermedad Crónica , Glaucoma de Ángulo Abierto/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Hipotensión Ocular/diagnóstico , Choque Hemorrágico/complicaciones
12.
Am J Hosp Pharm ; 49(11): 2727-30, 1992 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1471637

RESUMEN

A peer-review system for monitoring pharmacists' practice in medication-refill clinics is described. Pharmacist practitioners trained in pharmacology, therapeutics, and physical assessment provide services in three medication-refill clinics associated with a 350-bed Department of Veterans Affairs (VA) medical center. The clinics serve patients who have exhausted their prescribed drugs before their next appointment with a physician. During a clinic visit, the pharmacist assesses the patient and the drug therapy and either consults an attending physician or writes new prescriptions. The pharmacist documents his or her activities in the medical record. The peer-review mechanism involves quarterly audits in which the chart notes written by the pharmacists are reviewed by other pharmacists. Five indicators of the quality of care are used in the peer reviews. The results are presented to the ambulatory-care and quality assurance pharmacy committees for analysis and discussion. The peer-review system has resulted in better compliance by the pharmacists with the quality indicators and clinic procedures, suggesting that the quality of care has also benefited. Peer review is used successfully to evaluate and monitor the care provided by pharmacists in medication-refill clinics associated with a VA medical center.


Asunto(s)
Servicio Ambulatorio en Hospital/normas , Revisión por Pares , Servicio de Farmacia en Hospital/normas , Garantía de la Calidad de Atención de Salud/organización & administración , California , Prescripciones de Medicamentos , Hospitales con 300 a 499 Camas , Hospitales de Veteranos/normas , Humanos , Servicio Ambulatorio en Hospital/organización & administración , Revisión por Pares/métodos , Farmacéuticos , Servicio de Farmacia en Hospital/organización & administración , Desarrollo de Programa , Evaluación de Programas y Proyectos de Salud
13.
J Pharmacol Exp Ther ; 290(1): 289-94, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10381789

RESUMEN

Transport characteristics of 17beta-estradiol 17beta-D-glucuronide (E217betaG), a dual substrate of the transporters for cellular uptake (organic anion-transporting polypeptide 1 or oatp1) and cellular excretion (multidrug resistance-associated protein 1or MRP1), in the rat choroid plexus were studied in vivo and in vitro. The uptake of E217betaG into isolated choroid plexus was mediated by an energy-dependent system with a Km of 3.4 microM. Together with the previous finding that oatp1 is localized on the apical membrane of choroid plexus, these results suggest that oatp1 is responsible for the uptake of this ligand. After intracerebroventricular administration, elimination of E217betaG from cerebrospinal fluid was probenecid sensitive and much more rapid than that of inulin; less than 2% of the administered E217betaG and 40 to 50% of inulin remained in the cerebrospinal fluid 20 min after intracerebroventricular administration. In addition, the amount of E217betaG associated with choroid plexus at 20 min was negligible, suggesting the presence of an efficient excretion system on the basolateral membrane of choroid plexus. Expression of MRP1 was detected in choroid plexus. Semiquantitative reverse transcription-polymerase chain reaction and Western blot analyses indicated that the expression level of MRP1 in choroid plexus is about four or five times higher than that in the lung, one of the tissues exhibiting high expression of MRP1. Together with the in vivo vectorial transport of E217betaG, these results can be accounted for by assuming that there is basolateral localization of MRP1 in choroid plexus. Combined, oatp1 and MRP1 may synergistically mediate the efficient transcellular transport of E217betaG across choroid plexus.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Proteínas Portadoras/metabolismo , Plexo Coroideo/metabolismo , Resistencia a Múltiples Medicamentos , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Animales , Proteínas de Transporte de Anión , Transporte Biológico Activo , Western Blotting , Epitelio/metabolismo , Estradiol/análogos & derivados , Estradiol/líquido cefalorraquídeo , Estradiol/metabolismo , Técnicas In Vitro , Inyecciones Intraventriculares , Cinética , Masculino , Péptidos/metabolismo , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
14.
Anat Histol Embryol ; 32(2): 89-93, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12797529

RESUMEN

Present electron microscopical and immunocytochemistrical studies elucidated some morphological relationship between intercalated duct (ICD) and pancreatic islet cells in the chicken in streptozotocin (STZ) and/or camostat mesilate (CM) administrations. Twenty-one chickens were set into four experimental groups: (1) control group, (2) STZ administration group, (3) CM administration group, and (4) STZ + CM administration group. Cytoplasms of ICD cells stained more strongly with eosin in STZ administration group than other groups, and electron-dense materials and intercalated processes between ICD and islet cells were also increasing in time dependence in STZ administration. Number of pancreatic islet in STZ + CM co-administration was about 3.1 times larger than other groups. Many small sized cells were detected at surrounding area of ICD and they incorporated 5-bromo-2'-deoxyuridine better than other experimental groups. Present morphological data suggested that ICD cells might support some tolerances of pancreatic endocrine cells against toxic substances and also involve in regeneration of new pancreatic islet cells in STZ + CM co-administration.


Asunto(s)
Pollos/anatomía & histología , Gabexato/análogos & derivados , Gabexato/toxicidad , Islotes Pancreáticos/efectos de los fármacos , Conductos Pancreáticos/efectos de los fármacos , Estreptozocina/toxicidad , Inhibidores de Tripsina/toxicidad , Animales , Ésteres , Guanidinas , Inmunohistoquímica/veterinaria , Islotes Pancreáticos/citología , Islotes Pancreáticos/ultraestructura , Microscopía Electrónica/veterinaria , Conductos Pancreáticos/citología , Conductos Pancreáticos/ultraestructura , Distribución Aleatoria
15.
Can Anaesth Soc J ; 31(1): 24-7, 1984 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6692176

RESUMEN

We measured plasma cortisol levels during surgery in seven neonates within ten days after birth and in 14 infants ranging in age from three months to 11 months. The 14 infants were divided into two groups; Group I included eight infants in whom general anaesthesia was maintained with oxygen, nitrous oxide and a muscle relaxant, Group II, six infants in whom general anaesthesia was maintained with oxygen, nitrous oxide, halothane and a muscle relaxant. In the neonates, the changes in mean plasma cortisol levels during anaesthesia were not statistically significant. In both Group I and Group II infants, the mean cortisol levels gradually rose during anaesthesia, but the initial rise in plasma cortisol levels was suppressed in the patients who received halothane.


Asunto(s)
Anestesia General , Hidrocortisona/sangre , Abdomen/cirugía , Femenino , Halotano/administración & dosificación , Humanos , Lactante , Recién Nacido , Periodo Intraoperatorio , Masculino , Óxido Nitroso/administración & dosificación , Pancuronio/administración & dosificación , Radioinmunoensayo
16.
Blood ; 97(2): 419-25, 2001 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-11154218

RESUMEN

The CD34 antigen serves as an important marker for primitive hematopoietic cells in therapeutic transplantation of hematopoietic stem cells (HSC) and gene therapy, but it has remained an open question as to whether or not most HSC express CD34. Using a competitive long-term reconstitution assay, the results of this study confirm developmental changes in CD34 expression on murine HSC. In fetuses and neonates, CD34 was expressed on Lin(-)c-Kit(+) long-term repopulating HSC of bone marrow (BM), liver, and spleen. However, CD34 expression on HSC decreased with aging, and in mice older than 10 weeks, HSC were most enriched in the Lin(-)c-Kit(+)CD34(-) marrow cell fraction. A second transplantation was performed from primary recipients who were transplanted with neonatal Lin(-)c-Kit(+) CD34(high) HSC marrow. Although donor-type HSC resided in CD34-expressing cell fraction in BM cells of the first recipients 4 weeks after the first transplantation, the stem cell activity had shifted to Lin(-)c-Kit(+)CD34(-) cells after 16 weeks, indicating that adult Lin(-)c-Kit(+)CD34(-) HSC are the progeny of neonatal CD34-expresssing HSC. Assays for colony-forming cells showed that hematopoietic progenitor cells, unlike HSC, continue to express CD34 throughout murine development. The present findings are important because the clinical application of HSC can be extended, in particular as related to CD34-enriched HSC and umbilical cord blood HSC.


Asunto(s)
Antígenos CD34/metabolismo , Trasplante de Células , Células Madre Hematopoyéticas/inmunología , Factores de Edad , Animales , Animales Recién Nacidos , Células de la Médula Ósea/inmunología , Trasplante de Médula Ósea , Ensayo de Unidades Formadoras de Colonias , Feto/inmunología , Hígado/citología , Hígado/inmunología , Ratones , Ratones Endogámicos C57BL , Bazo/citología , Bazo/inmunología , Bazo/trasplante
17.
Blood ; 98(1): 6-12, 2001 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-11418454

RESUMEN

There is controversy as to whether murine definitive hematopoiesis originates from yolk sac (YS) or the intraembryonic region. This study reports the generation of definitive hematopoietic stem cells (HSCs) from both early YS and intraembryonic paraaortic splanchnopleures (P-Sp) on AGM-S3 stromal cells derived from the aorta-gonad-mesonephros (AGM) region at 10.5 days post coitum (dpc). YS and P-Sp cells at 8.5 dpc generated no definitive hematopoiesis-derived colony-forming cells in cocultures with AGM-S3 cells, but spleen colony-forming cells and HSCs capable of reconstituting definitive hematopoiesis in adult mice simultaneously appeared on day 4 of coculture. Precursors for definitive HSCs were present in YS and P-Sp at 8.0 dpc, a time when YS and embryo were not connected by blood vessels. It is proposed that precursors with the potential to generate definitive HSCs appear independently in YS and intraembryonic P-Sp and that the P-Sp or AGM region affords the microenvironment that facilitates generation of definitive hematopoiesis from precursors.


Asunto(s)
Sistema Digestivo/citología , Células Madre Hematopoyéticas/citología , Células del Estroma/citología , Saco Vitelino/citología , Animales , Aorta/citología , Células Sanguíneas/citología , Línea Celular , Técnicas de Cocultivo , Sistema Digestivo/embriología , Gónadas/citología , Supervivencia de Injerto , Hematopoyesis , Trasplante de Células Madre Hematopoyéticas , Hemoglobinas/metabolismo , Mesonefro/citología , Ratones , Ratones Endogámicos C57BL , Circulación Esplácnica/fisiología , Saco Vitelino/fisiología
18.
J Pharmacol Exp Ther ; 298(1): 316-22, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11408557

RESUMEN

The contribution of organic anion transporters to the total efflux of 17beta-estradiol-D-17beta-glucuronide (E(2)17betaG) through the blood-brain barrier (BBB) was investigated using the Brain Efflux Index method by examining the inhibitory effects of probenecid, taurocholate (TCA), p-aminohippurate (PAH), and digoxin. E(2)17betaG was eliminated through the BBB with a rate constant of 0.037 min(-1) after the microinjection into the brain. Probenecid and TCA inhibited this elimination with an IC50 value of 34 and 1.8 nmol/0.5 microl of injectate, respectively, whereas PAH and digoxin reduced the total efflux to about 80 and 60% of the control value, respectively. The selectivity of these inhibitors was confirmed by examining their inhibitory effects on the transport via organic anion transporting polypeptide 1 (Oatp1), Oatp2, organic anion transporter 1 (Oat1), and Oat3 transfectants using LLC-PK1 cells as hosts. Digoxin specifically inhibited the transport via Oatp2 (K(i) = 0.037 microM). The K(i) values of TCA for Oatp1 and Oatp2 (11 and 39 microM, respectively) were about 20 times lower than those for Oat1 and Oat3 (2.8 and 0.8 mM, respectively). PAH did not affect the transport via the Oatp family, but had a similar affinity for Oat1 and Oat3 (85 and 300 microM, respectively). Probenecid had a similar affinity for these transporters (Oatp1, Oatp2, Oat1, and Oat3) examined in this study. Taking the selectivity of these inhibitors into consideration, the maximum contribution made by the Oatp2 and Oat family to the total efflux of E(2)17betaG from the brain appears to be about 40 and 20%, respectively.


Asunto(s)
Barrera Hematoencefálica/fisiología , Encéfalo/metabolismo , Proteínas Portadoras/metabolismo , Estradiol/análogos & derivados , Estradiol/farmacocinética , Glucuronatos/farmacocinética , Transportadores de Anión Orgánico Sodio-Independiente , Animales , Proteínas de Transporte de Anión , Proteínas Portadoras/antagonistas & inhibidores , Digoxina/farmacología , Inhibidores Enzimáticos/farmacología , Estradiol/administración & dosificación , Glucuronatos/administración & dosificación , Masculino , Microinyecciones , Probenecid/farmacología , Ratas , Ratas Wistar , Ácido Taurocólico/farmacología , Ácido p-Aminohipúrico/farmacología
19.
Blood ; 98(13): 3618-25, 2001 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-11739165

RESUMEN

Although erythropoietin (EPO) and its receptor (EPOR) are crucial for the proliferation, survival, and terminal differentiation of erythroid progenitors, it remains to be elucidated whether EPOR-unique signaling is required for erythropoiesis. To address this issue, human granulocyte-macrophage colony-stimulating factor (hGM-CSF) receptor (hGMR)-transgenic mice and heterozygous EPOR mutant mice were crossed by in vitro fertilization. In methylcellulose clonal culture of fetal liver (FL) cells of generated hGMR-expressing EPOR(-/-) embryos at embryonic day (E) 12.5 of gestation, hGM-CSF stimulated erythroid colony formation under serum-containing and serum-free conditions. Analysis of globin expression in individual erythrocyte-containing colonies formed from E12.5 FL cells showed that hGM-CSF supports primitive and definitive erythropoiesis even in EPOR(-/-) embryos. In comparison of activities between hGM-CSF and EPO in hGMR-expressing EPOR(+/+) embryos, the 2 substances supported the formation of similar numbers of erythroid colonies in clonal culture of E12.5 FL cells; enhanced adult, but not embryonic, globin synthesis; and induced increase of GATA-1 expression and decrease of erythroid Kruppel-like factor and cMyb expression in the FL cells. On the other hand, in E8.0 yolk sac erythropoiesis, both substances had a similar effect on erythroid colony formation, but hGM-CSF induced an increase of beta-major globin expression, while EPO did not. All together, the results of the present study demonstrated that hGM-CSF can stimulate the proliferation and differentiation of primitive and definitive erythroid cells independently of EPOR signal if they express hGMR, and the activity is comparable to that of EPO in definitive, but not primitive, erythropoiesis.


Asunto(s)
Embrión de Mamíferos/metabolismo , Eritropoyesis , Expresión Génica , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Receptores de Eritropoyetina/genética , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/genética , Animales , Diferenciación Celular , División Celular , Células Cultivadas , Cruzamientos Genéticos , Proteínas de Unión al ADN/genética , Células Precursoras Eritroides/citología , Factores de Unión al ADN Específico de las Células Eritroides , Eritropoyetina/farmacología , Femenino , Fertilización In Vitro , Factor de Transcripción GATA1 , Edad Gestacional , Globinas/biosíntesis , Globinas/genética , Humanos , Ratones , Ratones Endogámicos ICR , Ratones Noqueados , Ratones Transgénicos , Receptores de Eritropoyetina/fisiología , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/fisiología , Transducción de Señal , Factores de Transcripción/genética
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