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1.
Cell Rep ; 42(7): 112730, 2023 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-37453057

RESUMEN

Cancer-associated mesothelial cells (CAMCs) in the tumor microenvironment are thought to promote growth and immune evasion. We find that, in mouse and human ovarian tumors, cancer cells express anti-Müllerian hormone (AMH) while CAMCs express its receptor AMHR2, suggesting a paracrine axis. Factors secreted by cancer cells induce AMHR2 expression during their reprogramming into CAMCs in mouse and human in vitro models. Overexpression of AMHR2 in the Met5a mesothelial cell line is sufficient to induce expression of immunosuppressive cytokines and growth factors that stimulate ovarian cancer cell growth in an AMH-dependent way. Finally, syngeneic cancer cells implanted in transgenic mice with Amhr2-/- CAMCs grow significantly slower than in wild-type hosts. The cytokine profile of Amhr2-/- tumor-bearing mice is altered and their tumors express less immune checkpoint markers programmed-cell-death 1 (PD1) and cytotoxic T lymphocyte-associated protein 4 (CTLA4). Taken together, these data suggest that the AMH/AMHR2 axis plays a critical role in regulating the pro-tumoral function of CAMCs in ovarian cancer.


Asunto(s)
Neoplasias Ováricas , Hormonas Peptídicas , Femenino , Humanos , Animales , Ratones , Hormona Antimülleriana/genética , Neoplasias Ováricas/genética , Ratones Transgénicos , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Microambiente Tumoral
3.
J Assist Reprod Genet ; 39(8): 1693-1712, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35870095

RESUMEN

Since 2007, the Oncofertility Consortium Annual Conference has brought together a diverse network of individuals from a wide range of backgrounds and professional levels to disseminate emerging basic and clinical research findings in fertility preservation. This network also developed enduring educational materials to accelerate the pace and quality of field-wide scientific communication. Between 2007 and 2019, the Oncofertility Consortium Annual Conference was held as an in-person event in Chicago, IL. The conference attracted approximately 250 attendees each year representing 20 countries around the world. In 2020, however, the COVID-19 pandemic disrupted this paradigm and precluded an in-person meeting. Nevertheless, there remained an undeniable demand for the oncofertility community to convene. To maintain the momentum of the field, the Oncofertility Consortium hosted a day-long virtual meeting on March 5, 2021, with the theme of "Oncofertility Around the Globe" to highlight the diversity of clinical care and translational research that is ongoing around the world in this discipline. This virtual meeting was hosted using the vFairs ® conference platform and allowed over 700 people to participate, many of whom were first-time conference attendees. The agenda featured concurrent sessions from presenters in six continents which provided attendees a complete overview of the field and furthered our mission to create a global community of oncofertility practice. This paper provides a synopsis of talks delivered at this event and highlights the new advances and frontiers in the fields of oncofertility and fertility preservation around the globe from clinical practice and patient-centered efforts to translational research.


Asunto(s)
COVID-19 , Preservación de la Fertilidad , Neoplasias , COVID-19/epidemiología , Humanos , Pandemias
4.
Curr Mol Med ; 16(3): 222-31, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26917267

RESUMEN

The MIS pathway is a potential therapeutic target in epithelial ovarian cancer (EOC): signaling requires both type II (T2R) and type I receptors (T1R), and results in growth inhibition. MISR2 is expressed in EOC, but the prevalence and relative contributions of candidate T1R remain unknown. We sought to: a) determine expression of T1R in EOC; b) assess impact of T1R expression with clinical outcomes; c) verify MIS-dependent Smad signaling and growth inhibition in primary EOC cell cultures. Tissue microarrays (TMA) were developed for analysis of T1Rs (ALK2/3/6) and MISR2 expression. Primary cell cultures were initiated from ascites harvested at surgery which were used to characterize response to MIS. TMA's from 311 primary cancers demonstrated the most common receptor combinations were: MISR2+/ALK2+3+6+ (36%); MISR2+/ALK2+3+6- (34%); MISR2-/ALK2+3+6- (18%); and MISR2-/ALK2+3+6+ (6.8%). No differences in overall survival (OS) were noted between combinations. The ALK6 receptor was least often expressed T1R and was associated with lower OS in early stage disease only (p =0.03). Most primary cell cultures expressed MISR2 (14/22 (63.6%)): 95% of these express ALK 2 and ALK3, whereas 54.5% expressed ALK6. MIS-dependent Smad phosphorylation was seen in the majority of cultures (75%). Treatment with MIS led to reduced cell viability at an average of 71% (range: 57-87%) in primary cultures. MIS signaling is dependent upon the presence of both MISR2 and specific T1R. In the majority of EOC, the T1R required for MIS-dependent signaling are present and such cells demonstrate appropriate response to MIS.


Asunto(s)
Receptores de Activinas Tipo I/genética , Hormona Antimülleriana/farmacología , Regulación Neoplásica de la Expresión Génica , Neoplasias Glandulares y Epiteliales/genética , Neoplasias Ováricas/genética , Isoformas de Proteínas/genética , Receptores de Péptidos/genética , Receptores de Factores de Crecimiento Transformadores beta/genética , Proteínas Smad/genética , Receptores de Activinas Tipo I/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Epitelial de Ovario , Femenino , Humanos , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Neoplasias Glandulares y Epiteliales/metabolismo , Neoplasias Glandulares y Epiteliales/mortalidad , Neoplasias Glandulares y Epiteliales/patología , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/mortalidad , Neoplasias Ováricas/patología , Ovario/metabolismo , Ovario/patología , Cultivo Primario de Células , Isoformas de Proteínas/metabolismo , Receptores de Péptidos/metabolismo , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Transducción de Señal , Proteínas Smad/metabolismo , Análisis de Supervivencia , Análisis de Matrices Tisulares , Células Tumorales Cultivadas
5.
Technology ; 1(1): 63-71, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24729676

RESUMEN

Mullerian Inhibiting Substance (MIS) has been shown to inhibit ovarian cancer cells both in-vitro and in-vivo. Furthermore, recent evidence suggests that MIS may effectively target a putative ovarian cancer progenitor cell population enriched by a panel of CD44+, CD24+, Ep-CAM+, and E-cadherin-cell surface markers. In order to accommodate clinical testing of MIS in ovarian cancer patients, the production of recombinant human MIS must be optimized to increase yield and purity. Here we show that, compared to wild type, the substitution of the MIS leader sequence to that of human serum albumin, combined with a modification of the endogenous cleavage site from RAQR/S to a furin/kex2 RARR/S consensus site results in high expression, increased C-terminus cleavage and a reduction in unwanted cryptic internal cleavage products when produced in CHO cells. Purified MIS containing these alterations retains its capacity to induce regression of the Mullerian duct in fetal rat embryonic urogenital ridge assays.

6.
Steroids ; 67(13-14): 1057-64, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12441191

RESUMEN

Metabolism of dehydroepiandrosterone (DHEA), its sulfate (DHEAS), and androstene-3,17-dione (delta(4)) was performed at their physiological plasma concentrations in MCF-7 cell cultures (1 microM, 10 and 2 nM, respectively). Final metabolic products of these steroids were separated by HPLC-radioactive flow detection and identified by LC/MS or MS/MS. Typical and specific mass fragmentation spectra identified the presence of estrone (E(1)), 17beta-estradiol (E(2)), delta(4), DHEA, 5-androstene-3beta,17beta-diol (delta(5)), and testosterone as principal DHEAS metabolites. Other steroids, such as androstenedione, androsterone, and DHEA fatty acid esters at very low concentrations (from pM to nM), were also obtained after steroid incubation. This highly specific method allowed us to conclude whether a metabolite and enzymatic activity of interest were present in MCF-7 cells or not. We also showed that DHEAS at its physiological plasma concentration may be converted into estrogens and estrogen-like compounds in breast cancer cells. The estrogenic action of DHEAS on breast cancer cells was also measured by bioluminescence in a stably transfected human breast cancer MCF-7 cell line with a reporter gene that allowed expression of the firefly luciferase enzyme under the control of an estrogen regulatory element.


Asunto(s)
Sulfato de Deshidroepiandrosterona/metabolismo , Estrógenos/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , División Celular , Deshidroepiandrosterona/metabolismo , Sulfato de Deshidroepiandrosterona/sangre , Sulfato de Deshidroepiandrosterona/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Genes Reporteros/genética , Espectrometría de Masas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas
7.
Food Chem Toxicol ; 40(10): 1311-25, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12387296

RESUMEN

A link between cardiovascular disease (CVD) mortality and the hardness of drinking water (DW) is suggested by about 30 epidemiological studies performed worldwide in the general population since 1957. This review examines the main ecological studies, case-control studies and cohort studies, published between 1960 and 2000. Attention is paid to the problem of interpretation of this typical result of environmental epidemiology. Some studies focused on the role played by inorganic elements known as DW contaminants (mainly, As, Pb) and above all on the role of the magnesium content of DW and its cardioprotective effects. To date, it would be impossible to understand this environmental findings without large intervention studies performed in well-controlled public health programs.


Asunto(s)
Enfermedades Cardiovasculares/mortalidad , Agua/análisis , Ingestión de Líquidos , Ecología , Exposición a Riesgos Ambientales , Humanos , Magnesio/análisis , Contaminantes del Agua/efectos adversos
8.
J Bone Miner Res ; 16(11): 2152-60, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11697813

RESUMEN

Fermentable carbohydrates have been shown to be nondigestible by human enzymes in the small intestine but are fermented extensively in the large bowel to short-chain fatty acids (SCFAs), which can increase mineral absorption. It has been shown that feeding such carbohydrates including short-chain fructo-oligosaccharides (sc-FOSs) increases intestinal magnesium (Mg) absorption in animals, but their beneficial impact on Mg absorption in humans still remains to be established. Therefore, this work aimed to investigate the effect of moderate daily doses of sc-FOSs (10 g/day) on the intestinal absorption and status of Mg in postmenopausal women without hormone replacement therapy (HRT). Eleven healthy postmenopausal women aged 59 +/- 6 years (mean +/- SD) received for 5 weeks sc-FOS or sucrose (placebo) treatments according to a randomized, double-blind, crossover design separated by a washout period of at least 3 weeks. Subjects ingested 87.5 mg of stable isotope 25Mg together with a fecal marker. Subsequently, feces were collected for 5-7 days. An inductively coupled plasma mass spectrometer (ICP/MS) was used for 25Mg stable isotope measurements in feces, urine, and blood. Mg levels were assessed also at the beginning and at the end of each treatment in plasma, erythrocytes, and urine. These measurements allowed for the determination of net intestinal Mg absorption and Mg status. The results show that the addition of 10 g sc-FOS to the diet increased Mg absorption by 12.3%, from 30.2 +/- 5.0% (placebo treatment) to 33.9 +/- 7.2% (sc-FOS treatment; mean +/- SD; p < 0.02). This increase in intestinal Mg absorption was accompanied by an increase in plasma 25Mg level and led to a higher urinary 25Mg excretion. This is the first time that such an effect is shown in humans. The overall conclusion of this work is that the ingestion of moderate doses of sc-FOS did improve intestinal Mg absorption and status in postmenopausal women. Because of the important role of Mg in many cellular functions, such Mg absorption improvement may be particularly interesting when the dietary intake of Mg is limited.


Asunto(s)
Carbohidratos de la Dieta/administración & dosificación , Absorción Intestinal/efectos de los fármacos , Magnesio/farmacocinética , Oligosacáridos/administración & dosificación , Anciano , Animales , Disponibilidad Biológica , Estudios Cruzados , Método Doble Ciego , Heces/química , Femenino , Humanos , Isótopos , Magnesio/sangre , Magnesio/orina , Persona de Mediana Edad
9.
J Am Soc Mass Spectrom ; 12(10): 1077-84, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11605968

RESUMEN

Potassium bromate salt clusters, [KBrO3]nKx(x+), formed by electrospray ionization were studied as a function of solution properties. Clusters with up to 4 positive charges were observed. Their abundance, charge state and distribution were shown to vary with the organic solvent in solution. The effects of 7 solvents, including methanol, ethanol, isopropanol, acetonitrile, acetone, pyridine, and 1,4-dioxane, were thoroughly investigated. Solvents with a low dielectric constant and a high viscosity seem to favor clustering in solution but do not systematically allow high charge state ion formation. On the other hand, cluster charge reduction during desolvation was not correlated with solvent cation affinity over the range of solvents examined. However, ion distribution in mass spectra could be rationalized as a combination of these two competing phenomena. Charge state increases with the cluster size but may be reduced during ion desolvation when high cation affinity solvent molecules are actually involved in the ion solvation shell. This assumption could be envisaged in either Iribarne or Dole mechanisms of ion release in the gas phase. However, intensity profiles of multiply charged clusters could only be understood in terms of the ion evaporation mechanism.

10.
Clin Chim Acta ; 310(2): 123-30, 2001 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-11498077

RESUMEN

BACKGROUND: Pentane in exhaled gas is often used as an index of lipoperoxidation, but today, there is no standardization for its measurement. In this study, with our technical experience, we determined basal production of pentane in healthy subjects, and we evaluated variability of pentane flow 1 month later. METHODS: 18 subjects inhaled hydrocarbon-free air (HCFA) in order to realize a lung washout. Ambient air and three samples (at T0, T10, T30 min) of expired gas were concentrated using a "trap-and-purge" procedure. For the analysis of pentane, an Al(2)O(3)/KCl plot column contained in a gas chromatograph equipped with a flame ionization detector was used. RESULTS: After 10 min of washout, mean (+/-SD) exhalation rate of pentane was 1+/-0.6 pmol min(-1) kg(-1). After 30 min of washout, mean (+/-SD) exhalation rate of pentane was 0.7+/-0.5 pmol min(-1) kg(-1). No significant difference in pentane flow was shown 1 month later for eight subjects who repeated the protocol. CONCLUSION: With our results and data of the literature, exhalation rates of pentane from healthy adults appear to range between 0.3 and 2 pmol min(-1) kg(-1). The variability of pentane flow 1 month later seems not very important.


Asunto(s)
Peroxidación de Lípido , Pentanos/metabolismo , Respiración , Adulto , Anciano , Cromatografía de Gases , Femenino , Ionización de Llama , Humanos , Masculino , Persona de Mediana Edad , Pentanos/análisis , Valores de Referencia
11.
Biomed Pharmacother ; 55(3): 163-9, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11325214

RESUMEN

In order to estimate cell damage caused by free radicals during oxygenotherapy, we investigated the time course of two markers of lipoperoxidation: pentane in breath and malondialdehyde (MDA) in blood during brief normobaric hyperoxia. Nine healthy subjects inhaled hydrocarbon-free air (HCFA) for 30 minutes, hydrocarbon-free 100% O2 (HCFO2) for 125 minutes and then HCFA for 70 minutes. After 15 minutes of washout with HCFA, ambient pentane was eliminated. After HCFO2, at T175 versus T30 (i.e., 145 min from the start of 100% HCFO2), pentane production increased (P< 0.05). MDA rose significantly at T155 min (i.e., 125 min from the start of HCFO2), versus T30 (P< 0.01). These results suggest that acute hyperoxia causes a moderate increase in lipid peroxidation in healthy subjects. The increase of pentane and MDA confirms that acute hyperoxia induces lipid peroxidation in healthy subjects.


Asunto(s)
Hiperoxia/metabolismo , Malondialdehído/sangre , Terapia por Inhalación de Oxígeno/efectos adversos , Pentanos/metabolismo , Anciano , Biomarcadores , Pruebas Respiratorias , Femenino , Humanos , Hidrocarburos/análisis , Hiperoxia/sangre , Masculino , Persona de Mediana Edad
12.
Sante Publique ; 13(3): 237-48, 2001 Sep.
Artículo en Francés | MEDLINE | ID: mdl-11826843

RESUMEN

On a daily basis, the community pharmacist is just as concerned with alcohol (when detecting the interactions between alcohol and medication, or the use of alcohol as an excipient or active ingredient), as with alcoholism (when filling prescriptions, providing advice and guidance to patients, or undertaking other health education actions). In order to define the pharmacist's perception of the problem of alcoholism, an opinion poll was conducted by direct interrogation using a standardised questionnaire. The poll surveyed the owners of 101 randomly selected pharmacies in Puy de Dome. All of the pharmacists questioned are sensitive to and aware of the problem of interactions resulting from mixing alcohol and medication at the time of filling prescriptions. On the other hand, their perception of alcoholism and their behavior towards alcoholic patients vary. They frequently stressed the difficulty of establishing a dialogue. In spite of receiving information and training on alcoholism, perceived as insufficient, pharmacists claim to be really concerned by this problem. As field workers, community pharmacists think that they have a major role to play in carrying out health education campaigns and alcoholism prevention. In fact, the pharmacy is a privileged setting for facilitating encounters and discussions, where alcoholism, like all public health problems, can be addressed.


Asunto(s)
Alcoholismo/prevención & control , Actitud del Personal de Salud , Perfil Laboral , Farmacias/organización & administración , Farmacéuticos/psicología , Pautas de la Práctica en Medicina/organización & administración , Rol Profesional , Adulto , Alcoholismo/psicología , Competencia Clínica/normas , Interacciones Farmacológicas , Femenino , Francia , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Necesidades , Educación del Paciente como Asunto , Relaciones Profesional-Paciente , Autoeficacia , Encuestas y Cuestionarios
13.
Environ Res ; 84(3): 219-27, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11097795

RESUMEN

Cardiovascular disease (CVD) has been the first cause of mortality in the population of Puy de Dôme (PDD) (France) between 1988 and 1992. The mortality rates are significantly higher than those observed in the whole population of France (for the female population, 354.8 versus 327.3 per 100,000 persons/year and for the male population, 335.7 versus 287.9 per 100,000 persons/year). Moreover, an ecological study, which used the Standardized Mortality Ratios (SMR) and performed at the canton level, has allowed a special variation of mortality from CVD in PDD to be described. A decreased gradient of mortality (especially, "Ischemic Heart diseases" [ICM-9, codes 410-414] and "Cerebro-vascular Diseases" [ICM-9, codes 430-438]) has been observed from the periphery (rural area) to the middle (urban area) of PDD. Moreover, a statistically significant negative relationship has been observed between the hardness of the drinking water supplies in PDD and the CVD mortality data (i.e., the lower the hardness of drinking water, the higher the SMR). Although, the low hardness of drinking water can contribute to the high CVD mortality observed among the PDD population, the role of other risk factors (i.e., biological, nutritional) must also be taken into consideration in further prospective studies.


Asunto(s)
Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/mortalidad , Contaminantes del Agua/efectos adversos , Abastecimiento de Agua , Adolescente , Adulto , Anciano , Niño , Preescolar , Estudios Epidemiológicos , Francia/epidemiología , Geografía , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Agua/química
14.
Biol Trace Elem Res ; 76(3): 245-56, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11049223

RESUMEN

Aluminum (Al) is toxic to certain biological systems and has been implicated as a neurotoxic agent in the pathogenesis of Alzheimer's disease. Intestinal absorption of Al is very low (0.1%), but many organic dietary components are potential chelators of Al and may enhance its absorption and tissue distribution. We examined the effects of acute and chronic coingestion of AlCl3 with different polyphenolic acids on Al retention and compared to citrate in rats. In experiment 1, animals fasted for 14 h were dosed orally with demineralized water, Al chloride, Al chloride plus sodium citrate, or Al chloride plus a polyphenol acid. Blood samples were taken before and 2 h after the gavage and animals were killed 6 h later. In experiment 2, the rats were adapted on a purified diet for 1 wk and received the following for 4 wk in their experimental diets: AlCl3, except group 1, plus citrate or a polyphenol acid, except groups 1 and 2. Animals were killed and blood and tissues were sampled. In experiment 1, citrate highly enhanced Al absorption and its tissue retention. Gallic and chlorogenic acids significantly increased tibia and kidney Al levels compared to the Al group. In experiment 2, Al levels in the urine were significantly increased in all the Al groups compared to the control group. Significantly higher Al levels in the tibia, kidney, and brain were observed in the citrate group and a significant increase in brain Al level was also noted in the chlorogenic acid group compared to AlCl3 group. This may suggest a possible relation structure-activity of polyphenol acids. However, further studies are necessary to better understand the influence of polyphenol acids on Al metabolism, in particular that of chlorogenic acid.


Asunto(s)
Compuestos de Aluminio/farmacología , Aluminio/farmacocinética , Cloruros/farmacología , Citratos/farmacología , Flavonoides , Fenoles/farmacología , Polímeros/farmacología , Aluminio/sangre , Cloruro de Aluminio , Animales , Dieta , Ingestión de Alimentos , Crecimiento/efectos de los fármacos , Indicadores y Reactivos , Absorción Intestinal/efectos de los fármacos , Masculino , Polifenoles , Ratas , Ratas Wistar , Espectrofotometría Atómica , Factores de Tiempo , Distribución Tisular
15.
J Nutr ; 130(5): 1309-13, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10801935

RESUMEN

Red wines contain many components such as polyphenols and ethanol that may influence mineral absorption. We report on studies in a rat model that were designed to investigate the extent to which short- and long-term intake of red wine or ethanol may influence (67)Zn and (65)Cu absorption in rats. Rats (n = 96) were divided into three groups, a control group that received demineralized water, a group that received red wine diluted with water (v/v) and an ethanol group that received 6% ethanol. Half of each group was used for the short-term study; the others were used for the long-term study. After 3 d (short-term study) or 28 d (long-term study) of beverage consumption, the rats were gavaged with 2 mL of solution containing 2027 nmol (67)Zn and 902 nmol (65)Cu. Subsequently, 3-d urinary and fecal collections were performed and analyzed for total and isotopic Zn and Cu. In the long-term study, blood, tibia and liver were also sampled for mineral status assessment. Neither short- nor long-term intake of red wine altered (67)Zn or (65)Cu absorption. In contrast, long-term (but not short-term) ethanol consumption significantly increased both (67)Zn and (65)Cu absorption compared with the control and red wine groups. The long-term consumption of ethanol or red wine did not affect blood or tissue Zn or Cu levels. In conclusion, short- or long-term consumption of red wine did not have a negative effect on intestinal absorption or tissue levels of zinc and Cu in rats.


Asunto(s)
Cobre/farmacocinética , Etanol/farmacología , Vino , Zinc/farmacocinética , Animales , Peso Corporal/efectos de los fármacos , Cobre/sangre , Cobre/orina , Dieta , Absorción Intestinal/efectos de los fármacos , Masculino , Tamaño de los Órganos/efectos de los fármacos , Ratas , Ratas Wistar , Distribución Tisular , Zinc/sangre , Zinc/orina
16.
J Nutr ; 130(2): 249-53, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10720178

RESUMEN

The rhamnogalacturonan-II dimer (dRG-II) forms strong complexes in vitro with lead (Pb) and other selected cations. We examined the in vivo bioavailability of Pb complexed with dRG-II and the effect of unleaded dRG-II on the intestinal absorption and tissue retention of Pb in rats. Forty male Wistar rats were divided into four groups. Each group consumed a purified control diet for 3 wk or the same diet supplemented with: i) 3 mg of Pb/kg, ii) 0.5 g of leaded dRG-II/kg, or iii) 0.5 g of leaded dRG-II/kg and 4.5 g of unleaded dRG-II/kg. The leaded dRG-II provided approximately 3 mg of Pb/kg of diet. A chemical balance study was conducted during the last 5 d of the 3-wk study, and blood and organs were sampled for Pb and mineral analyses. The apparent intestinal absorptions of Pb were 62.3, 15.2, 11.8 and -0.1%, and Pb balances were 1.9, 9.6, 5.6 and -0.2 microg/d for the control and the three experimental groups, respectively. The Pb complexed with dRG-II was less available than Pb acetate, as reflected by significantly lower blood and tissue Pb levels. The addition of unleaded dRG-II decreased the intestinal absorption and the tissue retention of Pb significantly. We further found that the apparent absorption and status of magnesium, zinc and iron were unaffected by Pb treatment or dRG-II addition. We conclude that dRG-II may be useful in decreasing toxicity related to chronic Pb exposure. Human studies will be necessary however, to further evaluate the clinical utility of this beneficial effect.


Asunto(s)
Absorción Intestinal/efectos de los fármacos , Plomo/farmacocinética , Pectinas/farmacología , Análisis de Varianza , Animales , Dieta , Ingestión de Alimentos/efectos de los fármacos , Crecimiento/efectos de los fármacos , Masculino , Metales/administración & dosificación , Metales/sangre , Ratas , Ratas Wistar , Distribución Tisular
17.
Ecotoxicol Environ Saf ; 44(1): 47-55, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10499988

RESUMEN

The effects of natural chelators [humic acids (HA), caffeic acid (CFA), p-coumaric acid (PCA), protocatechuic acid (PA), vanillic acid (VA), salicylic acid (SA), and 4-hydroxyacetophenone (HY)] and effects of well-known chelators [EDTA and citric acid (CA)] on the in vitro toxicity of aluminium (Al) were investigated with the L-929 murine, Vero simian, and MRC-5 human cell lines. Moderate in vitro cytotoxic effects were induced by Al on the three cell lines (IC(50) values ranking from 5.6 to 7.6 mM). Furthermore, an increased toxicity was observed when Al was concurrently administered with CA, SA, VA, PCA, and HY. Inversely, significant cytoprotective effects were noted with EDTA, HA, CFA, and PA. The role of chelators, and especially the position and the number of reactive moieties of the phenolic compounds tested, can be highlighted to explain the different toxicological Al behavior observed.


Asunto(s)
Aluminio/toxicidad , Quelantes/farmacología , Sustancias Húmicas/farmacología , Fenoles/farmacología , Aluminio/metabolismo , Animales , Línea Celular , Relación Dosis-Respuesta a Droga , Humanos , Ratones
18.
Chemosphere ; 38(13): 3155-68, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10230051

RESUMEN

Two experiments were performed to assess the impact of cadmium on the sewage lagoon wastewater treatment process. For each one, three laboratory-scale pilot plants with one tank receiving the same raw effluent were used; one plant served as control and the other two were contaminated once only with cadmium. In the first study, the effects of a shock load of two concentrations of cadmium chloride (60 and 300 micrograms/l) on the plant performance, microbial populations (protists and bacteria) and enzyme activities were determined. Initially, most of the performance parameters were affected concentration-dependently. A reduction in the protist population density and some influence on the total bacterial population were observed, and the potential enzymatic activities were also modified. A second experiment with a lower cadmium concentration (30 micrograms/l), supplied as chloride or sulphate, still perturbed most of the parameters studied, and the effects of the two cadmium salts were identical.


Asunto(s)
Cadmio/toxicidad , Eliminación de Residuos Líquidos , Microbiología del Agua , Bacterias/efectos de los fármacos , Bacterias/metabolismo , Cadmio/química , Cloruro de Cadmio/química , Cloruro de Cadmio/toxicidad , Compuestos de Cadmio/química , Compuestos de Cadmio/toxicidad , Fenómenos Químicos , Química Física , Enzimas/análisis , Modelos Biológicos , Sulfatos/química , Sulfatos/toxicidad
19.
Chemosphere ; 38(7): 1631-69, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10070737

RESUMEN

Among protozoa, Tetrahymena pyriformis is the most commonly ciliated model used for laboratory research. After a brief description of the morphology and biology of Tetrahymena pyriformis, this article focuses on the most important and recent investigations performed with this species in toxicology and ecotoxicology. The methodological features of its culture, and main tests, based on cell growth rate, biochemical markers, behavioral changes and motility, are discussed. Examples of xenobiotics (organic and inorganic substances, pharmaceutical drugs, water pollutants) tested with Tetrahymena pyriformis are also given.


Asunto(s)
Tetrahymena pyriformis , Pruebas de Toxicidad/métodos , Contaminación Química del Agua/efectos adversos , Xenobióticos/toxicidad , Animales , Biomarcadores , Técnicas de Cultivo de Célula , División Celular , Movimiento Celular
20.
Biol Trace Elem Res ; 63(2): 139-47, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9823440

RESUMEN

Aluminum (Al) absorption seems to be very low, but many factors can enhance it in animals and humans. In the present study, we investigated the acute effect of Na citrate on Al absorption by monitoring Al levels in blood and several tissues. For this purpose, 18 Wistar male rats were divided into 3 groups: control, Al, and Al + Na citrate. After a 14-h fasting period, animals were dosed orally with deionized water, or 2 mmol Al chloride, or 2 mmol Al chloride plus 2 mmol Na citrate. Blood samples were taken before and 1, 2, 4, and 6 h after the gavage. Al concentrations in blood, liver, tibia, kidney, and intestinal wall were determined by ICP-OES. In the Al and Al + citrate groups, Al blood concentrations peaked at 1 h and 2 h with higher levels in the Al + citrate group. Al gavage resulted in an increase in Al level in intestinal wall, but not in the other investigated tissues. Simultaneous gavage of citrate with Al significantly increased its tissue levels in tibia, kidney, and in intestinal wall. Our data show clearly that Al as chloride can be absorbed, but not well retained by the organism tissues. Furthermore, the model used in the present study is appropriate for acute studies to investigate the effect of various compounds on Al absorption in the rat.


Asunto(s)
Compuestos de Aluminio/farmacología , Aluminio/farmacocinética , Citratos/farmacología , Administración Oral , Aluminio/sangre , Aluminio/farmacología , Animales , Interacciones Farmacológicas , Absorción Intestinal , Masculino , Ratas , Ratas Wistar , Citrato de Sodio , Distribución Tisular
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