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1.
Hum Exp Toxicol ; 41: 9603271221106341, 2022.
Article in English | MEDLINE | ID: mdl-35786065

ABSTRACT

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.


Subject(s)
Dental Amalgam , Mercury , Adult , Female , Gases , Humans , Male , Nutrition Surveys
2.
Hum Exp Toxicol ; 32(4): 434-40, 2013 Apr.
Article in English | MEDLINE | ID: mdl-22893351

ABSTRACT

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.


Subject(s)
Dental Amalgam/toxicity , Glutathione Transferase/urine , Isoenzymes/urine , Kidney/drug effects , Mercury/toxicity , Adolescent , Biomarkers/urine , Child , Female , Glutathione S-Transferase pi/urine , Humans , Kidney/enzymology , Male , Portugal
3.
Toxicol Environ Chem ; 91(3-4): 735-749, 2009 Jun.
Article in English | MEDLINE | ID: mdl-24532866

ABSTRACT

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.

4.
Indian J Med Res ; 128(4): 383-411, 2008 Oct.
Article in English | MEDLINE | ID: mdl-19106436

ABSTRACT

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.


Subject(s)
Autistic Disorder/chemically induced , Mercury/toxicity , Environmental Exposure , Humans
5.
Clin Exp Rheumatol ; 22(6): 749-55, 2004.
Article in English | MEDLINE | ID: mdl-15638050

ABSTRACT

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.


Subject(s)
Hepatitis B Vaccines/adverse effects , Hepatitis B/epidemiology , Hepatitis B/prevention & control , Twins, Monozygotic , Adolescent , Adult , Adverse Drug Reaction Reporting Systems , Databases, Factual , Female , Humans , Male , Risk Factors
6.
Clin Exp Rheumatol ; 20(2): 217-20, 2002.
Article in English | MEDLINE | ID: mdl-12051402

ABSTRACT

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.


Subject(s)
Anthrax Vaccines/adverse effects , Joint Diseases/etiology , Adult , Adverse Drug Reaction Reporting Systems , Biological Warfare , Databases, Factual , Female , Humans , Male , Middle Aged , Retrospective Studies , Risk
8.
Clin Exp Rheumatol ; 20(6): 767-71, 2002.
Article in English | MEDLINE | ID: mdl-12508767

ABSTRACT

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.


Subject(s)
Adverse Drug Reaction Reporting Systems/statistics & numerical data , Arthritis, Rheumatoid/etiology , Databases, Factual , Hepatitis B Vaccines/adverse effects , Rubella Vaccine/adverse effects , Vaccination/adverse effects , Adult , Arthritis, Rheumatoid/epidemiology , Female , Humans , Male , Middle Aged , Retrospective Studies , United States/epidemiology , Vaccination/statistics & numerical data
9.
Prenat Diagn ; 21(8): 676-9, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11536270

ABSTRACT

We report the prenatal diagnosis of a fetus with a de novo Robertsonian translocation: 45,XY,der(15;15)(q10;q10). Although Robertsonian translocations are common chromosomal rearrangements, those involving homologous chromosomes are infrequent. Since chromosome 15 is imprinted, uniparental disomy (UPD) is a concern when chromosomal rearrangements involving chromosome 15 are identified. In the present case, UPD studies showed normal biparental inheritance. In contrast to the fact that most homologous acrocentric rearrangements are isochromosomes, these results indicate postzygotic formation of a Robertsonian translocation between biparentally inherited chromosomes 15.


Subject(s)
Chromosomes, Human, Pair 15 , Translocation, Genetic/genetics , Adult , Cytogenetic Analysis , Diagnosis, Differential , Female , Genetic Counseling , Humans , Infant, Newborn , Karyotyping , Male , Maternal Age , Pregnancy , Pregnancy Trimester, Second , Pregnancy, High-Risk , Prenatal Diagnosis
11.
Clin Exp Rheumatol ; 19(6): 724-6, 2001.
Article in English | MEDLINE | ID: mdl-11791647

ABSTRACT

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.


Subject(s)
Adverse Drug Reaction Reporting Systems/statistics & numerical data , Arthritis/etiology , Databases, Factual/statistics & numerical data , Rubella Vaccine/adverse effects , Vaccination/adverse effects , Adult , Female , Humans , Male , Retrospective Studies , Rubella/prevention & control , Vaccination/statistics & numerical data
18.
Appl Environ Microbiol ; 36(3): 445-9, 1978 Sep.
Article in English | MEDLINE | ID: mdl-727776

ABSTRACT

Twenty samples of commercial vaccines intended for administration to humans were assayed for the presence of bacterial endotoxins by using the Limulus amebocyte lysate test. Sixteen of the vaccines contained more than 0.1 ng of endotoxin per ml (which corresponds to 103 bacterial cell wall equivalents per ml in the undiluted vaccines). These results suggest that at some stage of preparation, the vaccines have contained varying amounts of gram-negative bacteria and may indicate the presence of other bacterial products as well. It might be useful to list the level of endotoxins, phage, and other contaminants on each vaccine lot to facilitate studies on any side effects of these contaminants. Selection of vaccine lots with the least endotoxin might reduce some of the adverse effects of vaccinations.


Subject(s)
Bacterial Toxins/analysis , Endotoxins/analysis , Viral Vaccines/analysis , Limulus Test , Viral Vaccines/adverse effects
19.
J Bacteriol ; 124(1): 558-61, 1975 Oct.
Article in English | MEDLINE | ID: mdl-170250

ABSTRACT

Escherichia coli K-12 deficient in galactose-1-phosphate uridyl transferase is capable of converting significant amounts of d-[1-(14)C]galactose to (14)CO(2), whereas strains deficient in other enzymes of the Leloir pathway cannot do so.


Subject(s)
Carbon Dioxide/biosynthesis , Escherichia coli/metabolism , Galactose/metabolism , Mutation , Nucleotidyltransferases/biosynthesis , UTP-Hexose-1-Phosphate Uridylyltransferase/biosynthesis , Escherichia coli/enzymology , Phenotype , Phosphotransferases/biosynthesis , UDPglucose 4-Epimerase/biosynthesis
20.
Am J Clin Nutr ; 28(9): 947-9, 1975 Sep.
Article in English | MEDLINE | ID: mdl-1163478

ABSTRACT

Leucine-starved mice placed on a diet supplemented with the immediate precursor of leucine, alpha-ketoisocaproic acid, regain lost weight. This weight gain is similar to that observed when the leucine-starved mice are provided with leucine in their diet. Mice on a leucine-free diet supplemented with alpha-ketoisovaleric acid, the first compound in the leucine biosynthetic pathway, continued to lose weight as quickly as mice on leucine-deficient diets.


Subject(s)
Caproates/therapeutic use , Leucine/deficiency , Animals , Bacteria/metabolism , Deficiency Diseases/drug therapy , Leucine/biosynthesis , Leucine/therapeutic use , Mice , Structure-Activity Relationship , Valerates/therapeutic use
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