Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
2.
Ochsner J ; 22(4): 366-371, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36561103

RESUMEN

Background: Osteopetrosis includes a variety of rare inherited skeletal disorders characterized by increased bone density and thickness. It has different clinical forms, including infantile autosomal recessive, intermediate autosomal recessive, and late-onset autosomal dominant forms. Intermediate autosomal recessive osteopetrosis (IARO) displays high variability. Case Report: A 10-year-old male presented to our pediatrics emergency department with abdominal distension, low-grade fever, and swelling of the right maxilla with associated discharge. His local physician had treated the lesion with drainage and aspiration of pus without improvement. Examination revealed pallor, hepatosplenomegaly, poor dentition, and dental caries. Eye examination showed reduced visual acuity, absent color vision, nystagmus, and bilateral optic nerve atrophy. Laboratory investigations showed anemia and thrombocytopenia. Radiography yielded classic features of osteopetrosis. Detailed intraoral examination revealed an area of exposed necrotic bone in the alveolar region of the right maxilla, leading to a diagnosis of IARO with underlying osteomyelitis. The intraoral wound was treated with bismuth iodoform paraffin paste dressing, and the infection was treated with antibiotics. Anemia and thrombocytopenia were managed supportively by transfusion of packed red blood cells and platelets. Conclusion: IARO commonly presents with multiple fractures, so the absence of fractures in our patient was unusual. Studies evaluating the intermediate variant are meager; hence, documenting its various presentations is essential to aid physicians in making early diagnoses. Osteomyelitis of the jaws is a feared complication in these patients. Therefore, practitioners need to be cautious of infections of dental origin.

4.
Glycobiology ; 31(11): 1444-1463, 2021 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-34350945

RESUMEN

Bladder cancer is the ninth most frequently diagnosed cancer worldwide, and there is a need to develop new biomarkers for staging and prognosis of this disease. Here we report that cell lines derived from low-grade and high-grade bladder cancers exhibit major differences in expression of glycans in surface glycoproteins. We analyzed protein glycosylation in three low-grade bladder cancer cell lines RT4 (grade-1-2), 5637 (grade-2), and SW780 (grade-1), and three high-grade bladder cancer cell lines J82COT (grade-3), T24 (grade-3) and TCCSUP (grade-4), with primary bladder epithelial cells, A/T/N, serving as a normal bladder cell control. Using a variety of approaches including flow cytometry, immunofluorescence, glycomics and gene expression analysis, we observed that the low-grade bladder cancer cell lines RT4, 5637 and SW780 express high levels of the fucosylated Lewis-X antigen (Lex, CD15) (Galß1-4(Fucα1-3)GlcNAcß1-R), while normal bladder epithelial A/T/N cells lack Lex expression. T24 and TCCSUP cells also lack Lex, whereas J82COT cells express low levels of Lex. Glycomics analyses revealed other major differences in fucosylation and sialylation of N-glycans between these cell types. O-glycans are highly differentiated, as RT4 cells synthesize core 2-based O-glycans that are lacking in the T24 cells. These differences in glycan expression correlated with differences in RNA expression levels of their cognate glycosyltransferases, including α1-3/4-fucosyltransferase genes. These major differences in glycan structures and gene expression profiles between low- and high-grade bladder cancer cells suggest that glycans and glycosyltransferases are candidate biomarkers for grading bladder cancers.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Fucosiltransferasas/metabolismo , Neoplasias de la Vejiga Urinaria/metabolismo , Biomarcadores de Tumor/genética , Células Cultivadas , Fucosiltransferasas/genética , Glicosilación , Humanos , Neoplasias de la Vejiga Urinaria/patología
5.
Artículo en Inglés | MEDLINE | ID: mdl-34207818

RESUMEN

Contaminants of Emerging Concern (CECs) with estrogenic or estrogenic-like activity have been increasingly detected in aquatic environments and have been an issue of global concern due to their potential negative effects on wildlife and human health. This study used the MCF-7 cell proliferation assay (E-Screen) to assess the estrogenic activity profiles in Maryland Coastal Bays (MCBs), a eutrophic system of estuaries impacted by human activities. Estrogenic activity was observed in all study sites tested. Water samples from MCBs increased MCF-7 cell proliferation above the negative control from 2.1-fold at site 8, located in Sinepuxent Bay close to the Ocean City Inlet, to 6.3-fold at site 6, located in Newport Bay. The proliferative effects of the sediment samples over the negative control ranged from 1.9-fold at the Assateague Island National Seashore site to 7.7-fold at the Public Landing site. Moreover, elevated cell proliferation (p < 0.05) was observed when cells were co-exposed with 17ß-Estradiol (E2), while reduction in cell proliferation was observed when cells were co-exposed with the antagonist ICI 182, 780 suggesting that cell proliferative effects were primarily mediated by the estrogen receptor (ER). These results suggest the occurrence of some estrogenic or hormonal-like compounds in the MCBs and are consistent with our previous findings based on vitellogenin analyses.


Asunto(s)
Bahías , Estrógenos , Proliferación Celular , Humanos , Células MCF-7 , Maryland
6.
Cureus ; 13(4): e14428, 2021 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-33996294

RESUMEN

Introduction A systematic review and meta-analysis of the available randomized controlled trials (RCTs) were conducted to investigate the efficacy and safety of dotinurad in hyperuricemic patients with or without gout. Dotinurad is a novel selective urate reabsorption inhibitor (SURI) that increases uric acid excretion by selectively inhibiting urate transporter 1 (URAT1). To the best of our knowledge, this is the first meta-analysis conducted to gauge the efficacy and safety of dotinurad.  Methods Electronic databases (PubMed, the Cochrane Library, and ClinicalTrials.gov) were searched from inception till March 2, 2021, according to the Preferred Reporting Items for Systematic Review and Meta-Analysis statement. Randomized controlled trials comparing the efficacy and safety of dotinurad with placebo- or active (febuxostat or benzbromarone) control were included. The eligible studies were analyzed with RevMan 5.3 Software (The Nordic Cochrane Centre, Cochrane Collaboration, Copenhagen). Results Four eligible studies, consisting of 684 hyperuricemic patients were included. The number of patients who achieved serum uric acid (sUA) levels ≤ 6.0 mg/dl favoured dotinurad 1 mg group as compared to placebo group (risk ratio {RR} = 39.27, 95% onfidence interval {CI}, 5.59 to 275.65; p = 0.0002), dotinurad 2 mg group compared with placebo group (RR = 45.36, 95% CI, 6.48 to 317.38; p= 0.0001), and dotinurad 4 mg group compared with placebo group (RR = 54.16, 95% CI, 7.76 to 377.77; p < 0.0001). Conversely, there was no significant difference in the number of patients who achieved the target sUA levels between dotinurad 2 mg and active control (RR = 1.00, 95% CI, 0.92 to 1.08; p = 0.91). Moreover, the percentage change in sUA levels from baseline to final visit favoured dotinurad 1 mg vs. placebo ((RR = 36.51, 95% CI, 33.00 to 40.02; p < 0.00001), dotinurad 2 mg vs. placebo (RR = 46.70, 95% CI, 42.53 to 50.87; p < 0.00001), and dotinurad 4 mg vs. placebo (RR = 63.84, 95% CI, 60.51 to 67.16; p < 0.00001), while no significant difference was seen in dotinurad 2 mg vs. active control (RR = -0.08, 95% CI, -4.27 to 4.11; p= 0.97). Compared with active or placebo control, dotinurad 2 mg showed no significant difference in the number of events of gouty arthritis (RR= 1.31, 95% CI, 0.47 to 3.71; p = 0.60), the number patients with adverse events (RR = 1.09, 95% CI, 0.91 to 1.30; p = 0.36), and the number of patients who experienced adverse drug reactions (RR = 1.00, 95% CI, 0.68 to 1.47; p = 0.99). Conclusion Dotinurad shows significant improvement in serum uric acid levels in hyperuricemic individuals with or without gout. Its urate-lowering effect is comparable to the commonly available anti-hyperuricemic agents. Moreover, it is effective at doses 1 mg, 2 mg, and 4 mg and well-tolerated at a dose of 2 mg.

7.
Int J Environ Res Public Health ; 10(10): 5209-20, 2013 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-24157516

RESUMEN

This study evaluated the kinetic signature of toxicity of four heavy metals known to cause severe health and environmental issues--cadmium (Cd), mercury (Hg) lead (Pb) arsenic (As)--and the mixture of all four metals (Mix) on MCF7 cancer cells, in the presence and absence of the antioxidant glutathione (GSH). The study was carried out using real time cell electronic sensing (RT-CES). RT-CES monitors in real time the electrical impedance changes at the electrode/culture medium interface due to the number of adhered cells, which is used as an index of cell viability. Cells were seeded for 24 h before exposure to the metals and their mixtures. The results showed that in the presence and absence of cellular glutathione, arsenic was the most cytotoxic of all five treatments, inducing cell death after 5 h of exposure. Lead was the least cytotoxic in both scenarios. In the presence of cellular GSH, the cytotoxic trend was As > Cd > MIX > Hg > Pb, while in the absence of GSH, the cytotoxic trend was As > Hg > MIX > Cd > Pb. The findings from this study indicate the significance of glutathione-mediated toxicity of the metals examined--particularly for mercury--and may be clinically relevant for disorders such as autism spectrum disorder where decreased glutathione-based detoxification capacity is associated with increased mercury intoxication.


Asunto(s)
Neoplasias de la Mama , Metales Pesados/toxicidad , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Cinética , Metales Pesados/administración & dosificación
8.
Biomed Sci Instrum ; 43: 116-21, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17487067

RESUMEN

In response to genotoxic agents, normal tissue cells are instructed by p53 either to perform DNA repair or to undergo apoptosis. Studies showed that chemo and/or radiotherapy damage both normal and cancerous cells indiscriminately. To this end, severe side effects inflicted by p53 activation in normal tissues, would possibly be abrogated by p53 inhibition. Pifithrin-alpha (PFT-alpha) is a reversible inhibitor of p53-mediated apoptosis, p53-dependent gene transcription, as well as down stream responsive gene function. The objective of this study was (1) to evaluate PFT-alpha for differential cellular protection in response to arsenic trioxide and cadmium chloride exposure of normal and neoplastic cells, and (2) to evaluate the transcriptional activation of p53 and p53-responsive genes in rat liver cells and HepG2 carcinoma cell line. Cell survival was detected by fluorescein diacetate (FDA) and fluorospectroscopy. Mean LC50 and (SD) for HepG2 cells following exposure to arsenic were 13.7 (+/-1.0) microg/ml with PFT- alpha and 13.4 (+/- 0.5) microg/ml without PFT-alpha (p>0.05). For rat liver cells it was 670 (+/- 8.15) microg/ml with and 573.15 (+/-1.0) microg/ml without PFT-alphha (p<0.05). On exposure to cadmium Chloride, LC50's were 6.95 (+/-2.5) microg/ml for HepG2 cell line in presence of PFT-alpha and 7.35 (+/-1.9) microg/ml in its absence (p>0.5). The results revealed significant differences from controls only upon exposure of rat liver cells to arsenic trioxide in presence of PFT-alpha. PFT-alpha inhibited the transactivation of p53 in rat liver cells and resulted in repression of Bcl2, PCNA, MDM2, Cyclin G and P21 genes by arsenic trioxide. HepG2 cells exposed to arsenic trioxide and PFT-alpha showed expression of only the P53 and PCNA genes. We conclude that PFT-alpha exhibits cytoprotective effect, modifies the detrimental influences of known genotoxic agents in normal cells and has the potential for use as an adjuvant to cancer therapy.


Asunto(s)
Arsénico/toxicidad , Benzotiazoles/administración & dosificación , Cadmio/toxicidad , Reparación del ADN/efectos de los fármacos , Hepatoblastoma/metabolismo , Hepatocitos/metabolismo , Proteínas de Neoplasias/metabolismo , Tolueno/análogos & derivados , Animales , Línea Celular Tumoral , Células Cultivadas , Citoprotección/efectos de los fármacos , Daño del ADN , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Regulación de la Expresión Génica/efectos de los fármacos , Hepatoblastoma/patología , Hepatocitos/efectos de los fármacos , Hepatocitos/patología , Humanos , Dosificación Letal Mediana , Neoplasias Hepáticas , Masculino , Ratas , Ratas Wistar , Tolueno/administración & dosificación , Proteína p53 Supresora de Tumor/antagonistas & inhibidores
9.
Int J Environ Res Public Health ; 3(1): 118-20, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16823084

RESUMEN

Although most researches with non-essential metals (NEMs) have been done with single or individual metals, in reality, organisms are often exposed to multiple contaminants at the same time through the air, food and water. In this study, we tested the toxicity of four NEMs, As, Cd, Pb, and Hg, individually and as a composite mixture using the microtox bioassay. This assay uses the reduction of bioluminescence of the bacterium Vibrio fischeri as a measure of toxicity. The concentrations of each chemical in the mixture were based on multiples of their maximum contaminant levels (MCLs) set by the U.S. EPA. The highest concentration of exposure was 20 times the MCL, which translated into 200, 100, 40 and 300 ppb for As, Cd, Hg and Pb, respectively. The ratio for the mixture from these concentrations was 10:5:2:15 for As, Cd, Hg and Pb, respectively. Among the individual metals tested, the ranking of toxicity was Hg>Pb>Cd>As based on the EC50 values of 109, 455, 508 and 768 ppb for Hg, Pb, Cd and As, respectively. The EC50 for the composite mixture was 495% MCL which translated into nominal concentrations of 49, 25, 10 and 74 ppb for As, Cd, Hg, and Pb, respectively. Overall, the EC50 value of each NEM within the mixture was lower than the EC50 of the individual chemical; an evidence of synergism for the mixture. The individual toxic units (TU) were 0.06, 0.05, 0.09, and 0.16 for As, Cd Hg, and Pb, respectively and the summed toxic unit (TU) was 0.37 (less than 1). This study provides needed scientific data necessary for carrying out complete risk assessment of As, Cd, Hg, and Pb mixtures of some priority compounds.


Asunto(s)
Aliivibrio fischeri/efectos de los fármacos , Metales/toxicidad , Luminiscencia
10.
J Environ Biol ; 26(1): 1-5, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16114454

RESUMEN

Vitellogenin (vtg) concentrations were measured in plasma and liver samples from 12 hybrid Tilapia oreochromis niloticus x O. aureus to compare concentrations in these tissues. The results were calculated under two different normalizations: volume per gram of sample used (similar to normalization usually published in the literature and typically used for ELISA) and volume per total protein (similar to normalization used in polyacrylamide gel electrophoresis; PAGE). It was observed that the normalization procedure used in PAGE (per gram total protein) minimized the method detection limit by about 1000 and 2500 times in plasma and liver respectively, compared to the normalization usually reported in the literature. It was also observed that normalizing per gram total protein makes it possible to eliminate a potential problem of accidental dilution of plasma samples during sample collection. Moreover, the normalization on a per gram of total protein makes it possible even to compare results from the two different methods namely PAGE and ELISA. It also allows comparison between different tissues. Using the normalization procedures as used in PAGE (per gram total protein) for liver and the normalization method as reported in literature for ELISA (per volume of sample used), it was observed that liver samples had higher vtg levels (mean: 62 microg vtg/g) compared to the corresponding plasma samples (mean: 0.24 microg vtg/ml). However, when both results were normalized per gram total protein all but one liver sample were lower (62 microg vtg/g) than the corresponding plasma concentrations (mean = 246 microg vtg/g).


Asunto(s)
Vitelogeninas/normas , Animales , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Peces , Vitelogeninas/análisis
11.
Int J Environ Res Public Health ; 2(2): 304-7, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16705832

RESUMEN

DNTs are considered possibly carcinogenic to humans (Group 2B) because there is inadequate evidence in humans for carcinogenicity though there is sufficient evidence in experimental animals. In this study, MCF-7 (breast) and MRC-5 (lung) cells were exposed to a serial dilution of 2,4 and 2,6 DNTs (control, 1-500 ppm) in 96 well tissue culture plates. After various time intervals (24, 48, 72 and 96 hrs) the plates were washed, and 100microl fluorescein diacetate solution (10 microg/ml in PBS) was added column wise to each well, and incubated at 37 C for 30 - 60 min before reading the fluorescence with a spectrofluorometer at excitation and emission wavelengths of 485 and 538 nm respectively. Spectrofluorometeric readings were converted to percentages of cell survival. Regression analysis was conducted to determine the relationship between cell survival and exposed concentration. Linear equations derived from the regression analysis were used to calculate the LC50 values. Results indicated that 2,6 DNT was more toxic to breast cells; LC50 values were 445 and 292 ppm at 24 and 48 hours respectively compared to 2,4 DNT showing LC50 values of 570 and 407 ppm at 24 and 48 hours, respectively. No significant differences in toxicity existed between the two chemicals with regard to lung cells. Contrary to the above observation, 2,4 DNT was more toxic to breast cells; LC50 values were 407 and 238 ppm at 24 and 48 hours respectively compared to lung cells showing LC50 values of 527 and 402 ppm at 24 and 48 hours respectively. No significant difference existed for 2,6 DNT between the two cell lines. Lungs cells were more resistant to the two chemicals.


Asunto(s)
Dinitrobencenos/toxicidad , Mama/citología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Humanos , Pulmón/citología
12.
J Environ Biol ; 25(1): 1-6, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15303697

RESUMEN

Embryos of the Japanese medaka (Oryzias latipes) were exposed to serial concentrations of atrazine (0, 25, 50, and 100 ppm) and arsenic trioxide (0, 0.025, 0.05, 0.1 ppm) until hatching. Stasis of circulation, blood islands, titanic convulsions, tube heart and mortality were observed in atrazine-treated embryos. Each endpoint exhibited a concentration-response relationship. Only 4% of the embryos hatched in the 25 ppm, and none in the 50 and 100 ppm, probably due to cell death attributed to the embryos' inability to break from the chorion. With arsenic exposure, hatching was inversely correlated to chemical concentration: 86%, 75% and 54% for 0.025, 0.05 and 0.1 ppm, respectively. Hatching periods were also reduced from 7-13 days in controls to 7-11 days in arsenic-treated embryos. This observation was more pronounced with the 0.05 ppm concentration, showing a reduction of about 4 days. Despite this shortage in hatching time, there were no observable morphological abnormalities, as seen with atrazine. The ecological significance of these findings and implications for the development of sublethal toxicity tests using Japanese medaka embryos are important.


Asunto(s)
Atrazina/toxicidad , Muerte Celular/efectos de los fármacos , Embrión no Mamífero/efectos de los fármacos , Óxidos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Anomalías Inducidas por Medicamentos , Animales , Trióxido de Arsénico , Arsenicales , Embrión no Mamífero/citología , Exposición a Riesgos Ambientales , Femenino , Dosificación Letal Mediana , Oryzias , Factores de Tiempo
13.
Mol Cell Biochem ; 255(1-2): 161-70, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14971657

RESUMEN

Lead is a non-essential element that exhibits a high degree of toxicity, especially in children. Most research on lead has focused on its effects on organ systems such as the nervous system, the red blood cells, and the kidneys which are considered to be the primary targets of lead toxicity. However, the molecular mechanisms by which it induces toxicity, and carcinogenesis remain to be elucidated. In this research, we performed the MTT assay to assess the cytotoxicity, and the CAT-Tox assay to assess the transcriptional responses associated with lead exposure to thirteen different recombinant cell lines generated from human liver carcinoma cells (HepG2), by creating stable transfectants of mammalian promoter chloramphenicol (CAT) gene fusions. Study results indicated that lead nitrate is cytotoxic to HepG2 cells, showing LD50 values of 49.0 +/- 18.0 microg/mL, 37.5 +/- 9.2 microg/mL, and 3.5 +/- 0.7 microg/mL for cell mortality upon 24, 48 and 72 h of exposure, respectively; indicating a dose- and time-dependent response with regard to the cytotoxic effect of lead nitrate. A dose-response relationship was also recorded with respect to the induction of stress genes in HepG2 cells exposed to lead nitrate. Overall, six out of the thirteen recombinant cell lines tested showed inductions to statistically significant levels (p < 0.05). At 50 microg/mL of lead nitrate, the average fold inductions were: 2.1 +/- 1.0, 5.4 +/- 0.4, 12.1 +/- 6.2, 5.0 +/- 1.7, 2.5 +/- 1.3, and 4.8 +/- 4.5 for XRE, HSP70, CRE, GADD153, and GRP78, respectively. These results indicate the potential for lead nitrate to undergo biotransformation in the liver (XRE), to cause cell proliferation (c-fos), protein damage (HSP70, GRP78), metabolic perturbation (CRE), and growth arrest and DNA damage (GADD153). Marginal but not significant inductions were also obtained with the GSTYa (1.5 +/- 0.8), and GADD45 (5.7 +/- 8.1) promoters, and the NF-KB (2.0 +/- 1.7) response element, indicating the potential for oxidative stress. No significant inductions (p > 0.05) were recorded for CYP1A1, HMTIIA, p53RE, and RARE.


Asunto(s)
Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Plomo/farmacología , Plomo/toxicidad , Nitratos/farmacología , Activación Transcripcional/efectos de los fármacos , Fusión Artificial Génica , División Celular/efectos de los fármacos , Cloranfenicol O-Acetiltransferasa/genética , Cloranfenicol O-Acetiltransferasa/metabolismo , Chaperón BiP del Retículo Endoplásmico , Humanos , Plomo/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Regiones Promotoras Genéticas/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transducción de Señal/efectos de los fármacos , Células Tumorales Cultivadas
14.
Rev Environ Health ; 18(3): 203-29, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14672515

RESUMEN

Dinitrotoluenes (DNTs) are nitroaromatic compounds appearing as pale yellow crystalline solids at room temperature. Dinitrotoluenes exist as a mixture of 2 to 6 isomers, with 2,4-DNT, and 2,6-DNT being the most significant. About 500 persons are estimated to be potentially exposed yearly to 2,4-DNT and 2,6-DNT during the production of munitions and explosives. The main route of human exposure at ammunition facilities is inhalation, but dermal contact and inadvertent ingestion can also be substantial. In factory workers, exposure to DNTs has been linked to many adverse health effects, including cyanosis, vertigo, headache, metallic taste, dyspnea, weakness and lassitude, loss of appetite, nausea, and vomiting. Other symptoms including pain or parasthesia in extremities, abdominal discomfort, tremors, paralysis, chest pain, and unconsciousness have also been reported. The primary targets of DNT toxicity are the hematopoietic system (pallor, cyanosis, anemia, and leukocytosis), the cardiovascular system (ischemic heart disease), the nervous system (muscular weakness, headache, dizziness, nausea, insomnia, and tingling pains in the extremities) and the reproductive system (reduction of sperm counts, alteration of sperm morphology, and aspermatogenesis). An association between DNT exposure and increased risk of hepatocellular carcinomas and subcutaneous tumors in rats, as well as renal tumors in mice, has been established. Epidemiologic studies of DNT toxicity have been limited to small groups of workers who had been occupationally exposed at various ammunitions production facilities. Clearly defining the health effects of DNTs with a high degree of confidence has therefore been difficult because of the multigenic nature of occupational exposure. In an attempt to update the toxicologic profile of the DNTs, we hereby provide a critical review of the environmental and toxicologic pathology of DNTs, with a special emphasis on their potential implications for public health.


Asunto(s)
Contaminantes Ocupacionales del Aire/envenenamiento , Enfermedades Cardiovasculares/etiología , Dinitrobencenos/envenenamiento , Dinitrobencenos/toxicidad , Exposición por Inhalación , Enfermedades Musculares/etiología , Exposición Profesional , Animales , Estudios Epidemiológicos , Humanos , Náusea/etiología , Dolor/etiología , Farmacocinética , Medición de Riesgo , Vómitos/etiología
15.
Biomed Sci Instrum ; 38: 41-6, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12085641

RESUMEN

In response to genotoxic agents, normal cells are instructed by p53 to either perform DNA repair or to commit suicide. Since chemo and/or radiotherapy damage both normal and cancerous cells, the use of PFT-alpha, a reversible inhibitor of down stream function of p53, was suggested as a temporary inhibitor of p53-induced cell damage. Our objective therefore, was (1) to assess the inherent response of HepG2 and rat liver cells to the effects of arsenic and cadmium and (2) to evaluate the role of PFT-alpha in the differential protection of rat liver and HepG2 cells. Following cellular growth to 90% confluency, exposure to cytotoxic agents in presence of PFT-alpha (10 ppm) or its absence was performed. Cell survival was detected fluorometrically using fluorescein diacetate (FDA) and an Ascent Fluoroskan. Toxicity index (LC50) was calculated from percent survival using regression analysis. Results showed an average of 46 fold inherent resistance of rat liver cells to arsenic in comparison to HepG2 cells (LC50 range of 573.15-670 vs. 13.4-13.7 ppm respectively). An average of 8 fold inherent resistance was also attributed to rat liver cells in response to cadmium (LC50 range of 57.72-58.1 vs. 6.99-7.35 ppm respectively). PFT-alpha did not show significant difference in protecting HepG2 cells against cadmium or arsenic. In contrast, there was significant difference in the protection of rat liver cells upon exposure to arsenic. We conclude that Pifithrin-alpha exhibits protection to normal cells, which can play an important role in cancer chemotherapy.


Asunto(s)
Cloruro de Cadmio/toxicidad , Citoprotección , Hígado/efectos de los fármacos , Hígado/patología , Óxidos/toxicidad , Tiazoles/farmacología , Tolueno/análogos & derivados , Tolueno/farmacología , Animales , Trióxido de Arsénico , Arsenicales , Benzotiazoles , Línea Celular/efectos de los fármacos , Línea Celular/patología , Relación Dosis-Respuesta a Droga , Ratas , Ratas Wistar , Análisis de Regresión
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA