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1.
Hum Exp Toxicol ; 41: 9603271221106341, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35786065

RESUMEN

OBJECTIVE: For more than 150 years, dental amalgam fillings (50% metallic mercury (Hg0) by weight) have been used in American dentistry. The US Food and Drug Administration (FDA) acknowledged that amalgams release Hg vapor that may be harmful to certain patients. This study examined the impact of Hg vapor exposure from amalgams in American adults. METHODS: Amalgam-Hg vapor exposure among 158,274,824 weighted-adult Americans was examined in the 2015-2018 National Health and Nutrition Examination Survey (NHANES). Beta (ß)-coefficients were calculated for the correlation between the number of amalgam surfaces and daily micrograms (µg) of urinary Hg and daily µg of Hg vapor exposure from amalgams per kilogram (Kg) bodyweight. RESULTS: About 91 million (57.8%) adults had ≥1 amalgam surface and about 67 million (42.2%) had no amalgams. A ß-coefficient = 0.041 significantly correlated the number of amalgam surfaces to daily amounts of urinary Hg. Differences were observed for gender and racial groups. Daily Hg vapor doses from amalgams were in excess of the most restrictive California's Environmental Protection Agency (EPA) safety limit for about 86 million (54.3%) adults and in excess of the least restrictive US EPA safety limit among about 16 million (10.4%) adults. The mean allowable number of amalgam surfaces ranged from 1.28 for adult females under the California's EPA safety limit to 16.23 for adult males under the US EPA safety limit. CONCLUSION: Given that American adults are receiving significant, ongoing exposure to Hg vapor from amalgams, careful evaluation of the need to reduce use of amalgams should be considered.


Asunto(s)
Amalgama Dental , Mercurio , Adulto , Femenino , Gases , Humanos , Masculino , Encuestas Nutricionales
2.
Hum Exp Toxicol ; 32(4): 434-40, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22893351

RESUMEN

Dental amalgams are a commonly used dental restorative material. Amalgams are about 50% mercury (Hg), and Hg is known to significantly accumulate in the kidney. It was hypothesized that because Hg accumulates in the proximal tubules (PTs), glutathione-S-transferases (GST)-α (suggestive of kidney damage at the level of PT) would be expected to be more related to Hg exposure than GST-π (suggestive of kidney damage at the level of the distal tubules). Urinary biomarkers of kidney integrity were examined in children of 8-18 years old, with and without dental amalgam fillings, from a completed clinical trial (parent study). Our study determined whether there was a significant dose-dependent correlation between increasing Hg exposure from dental amalgams and GST-α and GST-π as biomarkers of kidney integrity. Overall, the present study, using a different and more sensitive statistical model than the parent study, revealed a statistically significant dose-dependent correlation between cumulative exposure to Hg from dental amalgams and urinary levels of GST-α, after covariate adjustment; where as, a nonsignificant relationship was observed with urinary levels of GST-π. Furthermore, it was observed that urinary GST-α levels increased by about 10% over the 8-year course of the study among individuals with an average exposure to amalgams among the study subjects from the amalgam group, in comparison with study subjects with no exposure to dental amalgams. The results of our study suggest that dental amalgams contribute to ongoing kidney damage at the level of the PTs in a dose-dependent fashion.


Asunto(s)
Amalgama Dental/toxicidad , Glutatión Transferasa/orina , Isoenzimas/orina , Riñón/efectos de los fármacos , Mercurio/toxicidad , Adolescente , Biomarcadores/orina , Niño , Femenino , Gutatión-S-Transferasa pi/orina , Humanos , Riñón/enzimología , Masculino , Portugal
3.
Hum Exp Toxicol ; 31(1): 11-7, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21803780

RESUMEN

Dental amalgams are a commonly used dental restorative material, and amalgams are about 50% mercury (Hg). In our study, urinary Hg levels was examined in children of age 8-18 years, with and without dental amalgam fillings, from a completed clinical trial (parent study) that was designed to evaluate the potential health consequences of prolonged exposure to Hg from dental amalgam fillings. Our study was designed to determine whether there was a significant dose-dependent correlation between increasing Hg exposure from dental amalgams and urinary Hg levels. Hg exposure depends on the size and number of teeth with dental amalgams. Overall, consistent with the results observed in the parent study, there was a statistically significant dose-dependent correlation between cumulative exposure to Hg from dental amalgams and urinary Hg levels, after covariate adjustment. Further, it was observed that urinary Hg levels increased by 18% to 52% among 8 to 18 year old individuals, respectively, with an average exposure to amalgams, in comparison to study subjects with no exposure to amalgams. The results of our study suggest that dental amalgams contribute to ongoing Hg exposure in a dose-dependent fashion.


Asunto(s)
Amalgama Dental/farmacocinética , Caries Dental/orina , Restauración Dental Permanente , Mercurio/orina , Adolescente , Factores de Edad , Niño , Amalgama Dental/uso terapéutico , Caries Dental/terapia , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino
4.
Toxicol Environ Chem ; 91(3-4): 735-749, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24532866

RESUMEN

Thimerosal (ethylmercurithiosalicylic acid), an ethylmercury (EtHg)-releasing compound (49.55% mercury (Hg)), was used in a range of medical products for more than 70 years. Of particular recent concern, routine administering of Thimerosal-containing biologics/childhood vaccines have become significant sources of Hg exposure for some fetuses/infants. This study was undertaken to investigate cellular damage among in vitro human neuronal (SH-SY-5Y neuroblastoma and 1321N1 astrocytoma) and fetal (nontransformed) model systems using cell vitality assays and microscope-based digital image capture techniques to assess potential damage induced by Thimerosal and other metal compounds (aluminum (Al) sulfate, lead (Pb)(II) acetate, methylmercury (MeHg) hydroxide, and mercury (Hg)(II) chloride) where the cation was reported to exert adverse effects on developing cells. Thimerosal-associated cellular damage was also evaluated for similarity to pathophysiological findings observed in patients diagnosed with autistic disorders (ADs). Thimerosal-induced cellular damage as evidenced by concentration- and time-dependent mitochondrial damage, reduced oxidative-reduction activity, cellular degeneration, and cell death in the in vitro human neuronal and fetal model systems studied. Thimerosal at low nanomolar (nM) concentrations induced significant cellular toxicity in human neuronal and fetal cells. Thimerosal-induced cytoxicity is similar to that observed in AD pathophysiologic studies. Thimerosal was found to be significantly more toxic than the other metal compounds examined. Future studies need to be conducted to evaluate additional mechanisms underlying Thimerosal-induced cellular damage and assess potential co-exposures to other compounds that may increase or decrease Thimerosal-mediated toxicity.

5.
Indian J Med Res ; 128(4): 383-411, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19106436

RESUMEN

Emerging evidence supports the theory that some autism spectrum disorders (ASDs) may result from a combination of genetic/biochemical susceptibility, specifically a reduced ability to excrete mercury (Hg), and exposure to Hg at critical developmental periods. Elemental/inorganic Hg is released into the air/water where it becomes methylated and accumulates in animal tissues. The US population is primarily exposed to methyl-Hg by fish consumption. In addition, many pharmaceuticals have been, and some continue to be, a ubiquitous source of danger because they contain mercurials. Mercurials may be found in drugs for the eye, ear, nose, throat, and skin; in bleaching creams; as preservatives in cosmetics, tooth pastes, lens solutions, vaccines, allergy test and immunotherapy solutions; in antiseptics, disinfectants, and contraceptives; in fungicides and herbicides; in dental fillings and thermometers; and many other products. Hg has been found to cause immune, sensory, neurological, motor, and behavioural dysfunctions similar to traits defining/associated with ASDs, and that these similarities extend to neuroanatomy, neurotransmitters, and biochemistry. Furthermore, a review of molecular mechanisms indicates that Hg exposure can induce death, disorganization and/or damage to selected neurons in the brain similar to that seen in recent ASD brain pathology studies, and this alteration may likely produce the symptoms by which ASDs are diagnosed. Finally, a review of treatments suggests that ASD patients who undergo protocols to reduce Hg and/or its effects show significant clinical improvements in some cases. In conclusion, the overwhelming preponderance of the evidence favours acceptance that Hg exposure is capable of causing some ASDs.


Asunto(s)
Trastorno Autístico/inducido químicamente , Mercurio/toxicidad , Exposición a Riesgos Ambientales , Humanos
6.
Clin Exp Rheumatol ; 22(6): 749-55, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15638050

RESUMEN

OBJECTIVES: Adverse events and positive re-challenge of symptoms reported in the scientific literature and to the Vaccine Adverse Event Reporting System (VAERS) following hepatitis B vaccination (HBV) were examined. METHODS: The VAERS and PubMed (1966-2003) were searched for autoimmune conditions including arthritis, rheumatoid arthritis, myelitis, optic neuritis, multiple sclerosis (MS), Guillain Barré Syndrome (GBS), glomerulonephritis, pancytopenia/thrombocytopenia, fatigue, and chronic fatigue, and Systemic Lupus Erythematous (SLE) following HBV. RESULTS: HBV was associated with a number of serious conditions and positive re-challenge or significant exacerbation of symptoms following immunization. There were 415 arthritis, 166 rheumatoid arthritis, 130 myelitis, 4 SLE, 100 optic neuritis, 101 GBS, 29 glomerulonephritis, 283 pancytopenia/thrombocytopenia, and 183 MS events reportedfollowing HBV A total of 465 positive re-challenge adverse events were observed following adult HBV that occurred sooner and with more severity than initial adverse event reports. A case-report of arthritis occurring in identical twins was also identified. CONCLUSIONS: Evidence from biological plausibility, case-reports, case-series, epidemiological, and now for positive re-challenge and exacerbation of symptoms, and events in identical twins was presented. One would have to consider that there is causal relationship between HBV and serious autoimmune disorders among certain susceptible vaccine recipients in a defined temporal period following immunization. In immunizing adults, the patient, with the help of their physician, should make an informed consent decision as to whether to be immunized or not, weighing the small risks of the adverse effects of HBV with the risk of exposure to deadly hepatitis B virus.


Asunto(s)
Vacunas contra Hepatitis B/efectos adversos , Hepatitis B/epidemiología , Hepatitis B/prevención & control , Gemelos Monocigóticos , Adolescente , Adulto , Sistemas de Registro de Reacción Adversa a Medicamentos , Bases de Datos Factuales , Femenino , Humanos , Masculino , Factores de Riesgo
7.
Clin Exp Rheumatol ; 20(2): 217-20, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12051402

RESUMEN

OBJECTIVES: The purpose of this analysis was to evaluate anthrax vaccine (AVA) and joint related adverse reactions based upon analysis of the VAERS database in light of the current possibility of the use of anthrax as a biological warfare agent. METHODS: A certified copy of the VAERS database was obtainedfrom the CDC. In this study, we conducted a retrospective analysis using Microsoft Access for all joint attributed adverse reactions reported following anthrax vaccination. The employment of chi-square analysis determined if the elevated incidence rates of associated adverse reactions in anthrax vaccine recipients were statistically significant. RESULTS: Our analysis shows a very large and statistically significant increase in joint symptoms following vaccination with AVA when compared to our control population consisting of adverse joint reactions reported following vaccination with hepatitis A vaccine and Td vaccine. CONCLUSION: We believe that civilian doctors need to become familiar with the adverse reactions that can be expected to follow the use of AVA. Both civilian and military doctors need to be vigilant in reporting all such reactions to VAERS, so that more information can be gathered about AVA. We also believe that an anthrax vaccine with an improved safety profile is needed if it is to be used in populations, either military or civilian, that are not under imminent threat of attack by biological warfare agents. It should also be kept in mind that the widespread use of anthrax vaccination may cause potential producers of biological weapons and terrorists to seek to produce anthrax strains that are not neutralized by the current vaccine.


Asunto(s)
Vacunas contra el Carbunco/efectos adversos , Artropatías/etiología , Adulto , Sistemas de Registro de Reacción Adversa a Medicamentos , Guerra Biológica , Bases de Datos Factuales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Riesgo
9.
Clin Exp Rheumatol ; 20(6): 767-71, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12508767

RESUMEN

OBJECTIVES: This analysis examined the incidence rate of chronic arthritis adverse reactions reported following adult rubella and hepatitis B vaccinations. In this analysis, etiologic mechanisms for chronic arthritis following adult rubella and hepatitis B vaccines were also explored. METHODS: The Vaccine Adverse Events Reporting System (VAERS) database was analyzed for the incidence rate of reported cases of chronic arthritis in comparison to Tetanus-diphtheria (Td) and tetanus toxoid adult vaccine control groups. RESULTS: Chronic arthritis adverse reactions following adult rubella vaccination were primarily reported in females (female/male ratio = 3.0), at about 45 years-old, and at a mean onset time of 10-11 days following vaccination. Chronic arthritis adverse reactions following adult hepatitis B vaccination were also primarily reported in females(female/male ratio = 3.5), at about 33 years-old, and with a mean onset time of 16 days following vaccination. The incidence rates of chronic arthritis following adult rubella and adult hepatitis B vaccinations were statistically significantly increased, by chi 2 analysis, in comparison to the adult vaccine control groups. The attributable risk of chronic arthritis following adult rubella vaccine ranged from 32 to 53 and from 5.1 to 9.0 following adult hepatitis B vaccine in comparison to the adult vaccine control groups. CONCLUSION: This study revealed that adult rubella and adult hepatitis B vaccines were statistically associated with chronic arthritis which persisted for at least one year. The etiology for these adverse reactions may involve autoimmune mechanisms. Furthermore, potential biases in the reporting rates of adverse reactions to VAERS were not observed.


Asunto(s)
Sistemas de Registro de Reacción Adversa a Medicamentos/estadística & datos numéricos , Artritis Reumatoide/etiología , Bases de Datos Factuales , Vacunas contra Hepatitis B/efectos adversos , Vacuna contra la Rubéola/efectos adversos , Vacunación/efectos adversos , Adulto , Artritis Reumatoide/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Estados Unidos/epidemiología , Vacunación/estadística & datos numéricos
11.
Clin Exp Rheumatol ; 19(6): 724-6, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11791647

RESUMEN

OBJECTIVE: The United States Academy of Sciences, Institute of Medicine (IOM) reported in 1991 that the evidence indicates a causal relationship between the currently used rubella vaccine and acute and chronic arthritis. The purpose of this study was to analyze the associated arthritic reactions reported following rubella immunization from 1991 through 1998 to the Vaccine Adverse Events Reporting System (VAERS) database. METHODS: A certified copy of the VAERS database was obtained from the CDC. Microsoft Access was used to analyze the database. RESULTS: The results show that rubella vaccine is associated with a number of arthritic reactions reported to the VAERS database. CONCLUSION: Adult female patients need to make informed decisions on whether or not rubella vaccination is right for them. Doctors and patients must together make an informed consent decision about the risk verses the benefit to the patient in their particular life situation. Additionally, those patients who have had an adverse reaction to rubella vaccination should be informed that they may seek compensation under the no-fault Vaccine Compensation Act, which is administered by the US Claims Court.


Asunto(s)
Sistemas de Registro de Reacción Adversa a Medicamentos/estadística & datos numéricos , Artritis/etiología , Bases de Datos Factuales/estadística & datos numéricos , Vacuna contra la Rubéola/efectos adversos , Vacunación/efectos adversos , Adulto , Femenino , Humanos , Masculino , Estudios Retrospectivos , Rubéola (Sarampión Alemán)/prevención & control , Vacunación/estadística & datos numéricos
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