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1.
Artigo em Inglês | MEDLINE | ID: mdl-38432776

RESUMO

DNA alterations in gametes, which may occur either spontaneously or as a result of exposure to genotoxicants, can lead to constitutional chromosomal anomalies in the offspring. Alcohol is an established genotoxicant. The goal of this hypothesis-testing longitudinal cohort study was to evaluate the effect of significant/sustained maternal alcohol exposure on clinically diagnosed constitutional chromosomal anomalies among children diagnosed with fetal alcohol syndrome (FAS). De-identified eligibility and claim healthcare records, prospectively generated from the 1990-2012 Florida Medicaid system within the Independent Healthcare Research Database (IHRD), were analyzed. Children examined were continuously eligible with ≥ 8 outpatient office visits during the 96-month period following birth. Among these children, 377 were diagnosed with FAS and 137,135 were not. The incidence rate of chromosomal anomalies involving segregation (trisomy 13, 18, or 21, n = 625), microdeletions (microdeletion syndromes, n = 39), and point mutations (sickle-cell anemia/cystic fibrosis, n = 2570) were examined using frequency risk ratio (RR) and logistic regression (adjusted odds ratio (aOR) for sex, race, residence, socioeconomic/environmental exposure status, and birth date) models. The incidence rates of chromosomal anomalies involving segregation (RR=5.92, aOR=5.85) and microdeletions (RR=41.6, aOR=34.1) were significantly increased in the FAS cohort as compared to the non-diagnosed cohort, but there was no difference in the incidence rate of point mutations (RR=1.14, aOR=1.29). Maternal toxicant exposure should be considered in the etiology of constitutional chromosomal anomaly in offspring.


Assuntos
Transtornos Cromossômicos , Transtornos do Espectro Alcoólico Fetal , Criança , Estados Unidos , Feminino , Gravidez , Humanos , Estudos Longitudinais , Transtornos do Espectro Alcoólico Fetal/epidemiologia , Transtornos do Espectro Alcoólico Fetal/genética , Estudos de Coortes , Aberrações Cromossômicas
2.
J Clin Med Res ; 15(6): 310-320, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37434772

RESUMO

Background: The gut microbiome may play an important role in the etiology and progression of colon cancer. The present hypothesis-testing study compared the colon cancer incidence rate among adults diagnosed with intestinal Clostridioides (formerly Clostridium) difficile (Cdiff) (the Cdiff cohort) to adults not diagnosed with intestinal Cdiff infection (the non-Cdiff cohort). Methods: De-identified eligibility and claim healthcare records within the Independent Healthcare Research Database (IHRD) from a longitudinal cohort of adults (the overall cohort) enrolled in the Florida Medicaid system between 1990 through 2012 were examined. Adults with ≥ 8 outpatient office visits over 8 years of continuous eligibility were examined. There were 964 adults in the Cdiff cohort and 292,136 adults in the non-Cdiff cohort. Frequency and Cox proportional hazards models were utilized. Results: Colon cancer incidence rate in the non-Cdiff cohort remained relatively uniform over the entire study period, whereas a marked increase was observed in the Cdiff cohort within the first 4 years of a Cdiff diagnosis. Colon cancer incidence was significantly increased (about 2.7-fold) in the Cdiff cohort (3.11 per 1,000 person-years) compared to the non-Cdiff cohort (1.16 per 1,000 person-years). Adjustments for gender, age, residency, birthdate, colonoscopy screening, family history of cancer, and personal history of tobacco abuse, alcohol abuse/dependence, drug abuse/dependence, and overweight/obesity, as well as consideration of diagnostic status for ulcerative and infection colitis, immunodeficiency, and personal history of cancer did not significantly change the observed results. Conclusions: This is the first epidemiological study associating Cdiff with an increased risk for colon cancer. Future studies should further evaluate this relationship.

3.
Chemosphere ; 316: 137796, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36632954

RESUMO

Glyphosate-based herbicides (GBHs) are one of the most commonly used herbicides worldwide. Numerous in vitro and in vivo model system studies have demonstrated endocrine-disrupting chemical (EDC) properties associated with glyphosate/GBH exposure. The present hypothesis-testing study evaluated the potential inverse dose-dependent relationship between increasing urinary glyphosate and decreasing concentrations of blood sex hormones. Demographic and newly available lab test data from the 2013-2014 National Health and Nutrition Examination Survey (NHANES) were analyzed with survey regression modeling (adjusted for age, gender, race, and country of birth) in Statistical Analysis System (SAS) software. A total of 225, 615, 858 weighted-persons (sample n = 2130 persons) were examined for concentrations of urinary glyphosate and serum sex hormones (including: total testosterone, total estradiol, and sex hormone binding globulin (SHBG)) among males and females, 6 years-old or older. This study revealed about 82% of the population of the United States examined had detectable urinary concentrations of glyphosate. A significant inverse correlation between concentrations of glyphosate and total estradiol and a trend towards an inverse correlation between concentrations of glyphosate and total testosterone were observed. Concentrations of SHBG and glyphosate did not correlate. Ratios of total testosterone:SHBG and total estradiol:SHBG (estimating the fraction of active sex hormones in the blood) were significantly inversely correlated with urinary concentrations of glyphosate. This epidemiological study associates widespread and ongoing glyphosate/GBH exposures with human endocrine-disruptions. Future studies should examine these phenomena in other databases and other endocrine-related disorders.


Assuntos
Hormônios Esteroides Gonadais , Herbicidas , Masculino , Feminino , Humanos , Estados Unidos , Criança , Inquéritos Nutricionais , Hormônios Esteroides Gonadais/metabolismo , Testosterona , Estradiol , Globulina de Ligação a Hormônio Sexual/análise , Globulina de Ligação a Hormônio Sexual/metabolismo , Herbicidas/análise , Glifosato
4.
SAGE Open Med ; 9: 20503121211048677, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34691469

RESUMO

Objective: Mercury (Hg)-based amalgam is a dental restorative material in common use. This hypothesis-testing study evaluated the relationship between dental amalgam exposure and the risk of reported asthma diagnoses in American adults. Methods: A total of 97,861,577 weighted-persons with one or more dental amalgam surfaces (exposed group) and 31,716,558 weighted-persons with one or more other dental surfaces (no dental amalgams, unexposed group) were examined in the 2015-2016 National Health and Nutrition Examination Survey. All persons were 20-80 years old and with known reported asthma status (only newly diagnosed asthma cases were examined). Survey logistic regression and survey frequency modeling in SAS were employed to evaluate the relative incidence rate of reported asthma diagnoses among those in the exposed group compared to the unexposed group. Covariates of gender, race, socioeconomic status, educational status, country of birth, and tobacco exposure were considered. Results: Survey logistic modeling revealed a significantly increased incidence rate of reported asthma in the exposed group as compared to the unexposed group in unadjusted (4.46-fold) and adjusted (4.84-fold) models. A dose-response relationship was observed for the risk of reported asthma per dental amalgam filling surface in unadjusted (1.073) and adjusted (1.076) models. Survey frequency modeling revealed that the frequency of reported asthma (per 10,000 weighted-person years) was 3.66-fold significantly increased in the exposed group (2.06) as compared to the unexposed group (0.56). Conclusion: Increased dental amalgam exposure was associated with an increased risk of reported asthma diagnoses in American adults, but future studies should further evaluate this relationship.

5.
Med Hypotheses ; 140: 109760, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32344310

RESUMO

A novel virus named 2019 novel coronavirus (2019-nCoV/SARS-CoV-2) causes symptoms that are classified as coronavirus disease (COVID-19). Respiratory conditions are extensively described among more serious cases of COVID-19, and the onset of acute respiratory distress syndrome (ARDS) is one of the hallmark features of critical COVID-19 cases. ARDS can be directly life-threatening because it is associated with low blood oxygenation levels and can result in organ failure. There are no generally recognized effective treatments for COVID-19, but treatments are urgently needed. Anti-viral medications and vaccines are in the early developmental stages and may take many months or even years to fully develop. At present, management of COVID-19 with respiratory and ventilator support are standard therapeutic treatments, but unfortunately such treatments are associated with high mortality rates. Therefore, it is imperative to consider novel new therapeutic interventions to treat/ameliorate respiratory conditions associated with COVID-19. Alternate treatment strategies utilizing clinically available treatments such as hyperbaric oxygen therapy (HBOT), packed red blood cell (pRBC) transfusions, or erthropoiesis-stimulating agent (ESA) therapy were hypothesized to increase oxygenation of tissues by alternative means than standard respiratory and ventilator treatments. It was also revealed that alternative treatments currently being considered for COVID-19 such as chloroquine and hydroxychloroquine by increasing hemoglobin production and increasing hemoglobin availability for oxygen binding and acetazolamine (for the treatment of altitude sickness) by causing hyperventilation with associated increasing levels of oxygen and decreasing levels of carbon dioxide in the blood may significantly ameliorate COVID-19 respiratory symptoms. In conclusion, is recommend, given HBOT, pRBC, and ESA therapies are currently available and routinely utilized in the treatment of other conditions, that such therapies be tried among COVID-19 patients with serious respiratory conditions and that future controlled-clinical trials explore the potential usefulness of such treatments among COVID-19 patients with respiratory conditions.


Assuntos
Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/terapia , Pneumonia Viral/mortalidade , Pneumonia Viral/terapia , Acetazolamida/uso terapêutico , Antivirais/uso terapêutico , Betacoronavirus , COVID-19 , Capilares/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Transfusão de Eritrócitos , Hematínicos/uso terapêutico , Humanos , Oxigenoterapia Hiperbárica , Oxigênio/sangue , Pandemias , Síndrome do Desconforto Respiratório/diagnóstico , Síndrome do Desconforto Respiratório/virologia , SARS-CoV-2 , Tratamento Farmacológico da COVID-19
6.
SAGE Open Med ; 7: 2050312118822650, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30671241

RESUMO

OBJECTIVES: Asthma is a chronic disorder that affects persons of all ages impacting the quality of their lives. This cross-sectional hypothesis-testing study evaluated the relationship between human papillomavirus vaccine and the risk of an incident asthma diagnosis in a defined temporal period post-vaccination. METHODS: The 2015-2016 National Health and Nutrition Examination Survey data were examined for a group of 60,934,237 weighted persons between 9 and 26 years old in Statistical Analysis Software. RESULTS: Reported incident asthma significantly clustered in the year of reported human papillomavirus vaccination. When the data were separated by gender, the effects observed remained significant for males but not females. CONCLUSION: The results suggest that human papillomavirus vaccination resulted in an excess of 261,475 asthma cases with an estimated direct excess lifetime cost of such persons being US$42 billion. However, it is unclear what part of the vaccine and/or vaccine medium may have increased an individual's susceptibility to an asthma episode, whether the asthma diagnosis represented one asthma episode or if it is chronic, and how much therapeutic support was needed (if any) and for how long, which would impact cost. Despite the negative findings in this study, routine vaccination is an important public health tool, and the results observed need to be viewed in this context.

7.
Artigo em Inglês | MEDLINE | ID: mdl-29329213

RESUMO

The National Center for Education Statistics reported that between 1990-2005 the number of children receiving special education services (SES) rose significantly, and then, from 2004-2012, the number declined significantly. This coincided with the introduction of Thimerosal-containing hepatitis B vaccine in 1991, and the subsequent introduction of Thimerosal-reduced hepatitis B vaccine in the early 2000s. This study examined the potential relationship between infant exposure to mercury from three doses of Thimerosal-containing hepatitis B vaccine and the risk of boys being adversely affected (as measured by receipt of SES). This cross-sectional study examined 1192 boys (weighted n = 24,537,123) 7-8 years of age (born: 1994-2007) from the combined 2001-2014 National Health and Nutritional Examination Survey (NHANES). Survey logistic regression modeling revealed that an exposed population receiving three doses of infant Thimerosal-containing hepatitis B vaccine (weighted n = 11,186,579), in comparison to an unexposed population (weighted n = 704,254), were at an increased risk of receipt of SES. This association was robust (crude odds ratio = 10.143, p = 0.0232), even when considering covariates, such as race and socioeconomic status (adjusted odds ratio = 9.234, p = 0.0259). Survey frequency modeling revealed that receipt of SES for the population that was exposed to three doses of Thimerosal-containing hepatitis B vaccine in infancy (12.91%) was significantly higher than the unexposed population (1.44%) (prevalence ratio = 8.96, p = 0.006, prevalence attributable rate = 0.1147). Despite the limitation of this cross-sectional study not being able to ascribe a direct cause-and-effect relationship between exposure and outcome, it is estimated that an additional 1.2 million boys received SES with excess education costs of about United States (US) $180 billion associated with exposure to Thimerosal-containing hepatitis B vaccine. By contrast, exposure to Thimerosal-reduced hepatitis B vaccine was not associated with an increased risk of receiving SES. Therefore, routine childhood vaccination is important to reduce the morbidity and mortality of infectious diseases, but every effort should be made to eliminate Thimerosal from all vaccines.


Assuntos
Educação Inclusiva/estatística & dados numéricos , Vacinas contra Hepatite B/efeitos adversos , Transtornos do Neurodesenvolvimento/induzido quimicamente , Conservantes Farmacêuticos/efeitos adversos , Timerosal/efeitos adversos , Criança , Estudos Transversais , Educação Inclusiva/tendências , Vacinas contra Hepatite B/administração & dosagem , Humanos , Imunização/efeitos adversos , Modelos Logísticos , Masculino , Mercúrio/toxicidade , Inquéritos Nutricionais , Razão de Chances , Estados Unidos
8.
Sci Eng Ethics ; 23(6): 1691-1718, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29119411

RESUMO

Historically, entities with a vested interest in a product that critics have suggested is harmful have consistently used research to back their claims that the product is safe. Prominent examples are: tobacco, lead, bisphenol A, and atrazine. Research literature indicates that about 80-90% of studies with industry affiliation found no harm from the product, while only about 10-20% of studies without industry affiliation found no harm. In parallel to other historical debates, recent studies examining a possible relationship between mercury (Hg) exposure and autism spectrum disorder (ASD) show a similar dichotomy. Studies sponsored and supported by industry or entities with an apparent conflict of interest have most often shown no evidence of harm or no "consistent" evidence of harm, while studies without such affiliations report positive evidence of a Hg/autism association. The potentially causal relationship between Hg exposure and ASD differs from other toxic products since there is a broad coalition of entities for whom a conflict of interest arises. These include influential governmental public health entities, the pharmaceutical industry, and even the coal burning industry. This review includes a systematic literature search of original studies on the potential relationship between Hg and ASD from 1999 to August 2015, finding that of the studies with public health and/or industry affiliation, 86% reported no relationship between Hg and ASD. However, among studies without public health and/or industry affiliation, only 21% find no relationship between Hg and ASD. The discrepancy in these results suggests a bias indicative of a conflict of interest.


Assuntos
Transtorno do Espectro Autista/etiologia , Pesquisa Biomédica/ética , Conflito de Interesses , Exposição Ambiental/efeitos adversos , Indústrias/ética , Mercúrio/efeitos adversos , Transtorno Autístico/etiologia , Carvão Mineral , Indústria Farmacêutica , Ética nos Negócios , Ética em Pesquisa , Humanos , Saúde Pública
9.
Immunol Res ; 65(1): 46-54, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27406735

RESUMO

Gardasil is a quadrivalent human papillomavirus (HPV4) vaccine that was approved for use by the US Food and Drug Administration in June 2006. HPV4 vaccine is routinely recommended for administration to women in the USA who are 11-12 years old by the Advisory Committee on Immunization Practices. Previous studies suggest HPV4 vaccine administration was associated with autoimmune diseases. As a consequence, an epidemiological assessment of the vaccine adverse event reporting system database was undertaken for adverse event reports associated with vaccines administered from 2006 to 2014 to 6-39 year-old recipients with a listed US residence and a specified female gender. Cases with the serious autoimmune adverse event (SAAE) outcomes of gastroenteritis (odds ratio (OR) 4.627, 95 % confidence interval (CI) 1.892-12.389), rheumatoid arthritis (OR 5.629, 95 % CI 2.809-12.039), thrombocytopenia (OR 2.178, 95 % CI 1.222-3.885), systemic lupus erythematosus (OR 7.626, 95 % CI 3.385-19.366), vasculitis (OR 3.420, 95 % CI 1.211-10.408), alopecia (OR 8.894, 95 % CI 6.255-12.914), CNS demyelinating conditions (OR 1.585, 95 % CI 1.129-2.213), ovarian damage (OR 14.961, 95 % CI 6.728-39.199), or irritable bowel syndrome (OR 10.021, 95 % CI 3.725-33.749) were significantly more likely than controls to have received HPV4 vaccine (median onset of initial symptoms ranged from 3 to 37 days post-HPV4 vaccination). Cases with the outcome of Guillain-Barre syndrome (OR 0.839, 95 % CI 0.601-1.145) were no more likely than controls to have received HPV4 vaccine. In addition, cases with the known HPV4-related outcome of syncope were significantly more likely than controls to have received HPV4 vaccine (OR 5.342, 95 % CI 4.942-5.777). Cases with the general health outcomes of infection (OR 0.765, 95 % CI 0.428-1.312), conjunctivitis (OR 1.010, 95 % CI 0.480-2.016), diarrhea (OR 0.927, 95 % CI 0.809-1.059), or pneumonia (OR 0.785, 95 % CI 0.481-1.246) were no more likely than controls to have received HPV4 vaccine. Confirmatory epidemiological studies in other databases should be undertaken and long-term clinical consequences of HPV-linked SAAEs should be examined.


Assuntos
Doenças Autoimunes/etiologia , Vacinas contra Papillomavirus/efeitos adversos , Sistemas de Notificação de Reações Adversas a Medicamentos , Doenças Autoimunes/epidemiologia , Estudos de Casos e Controles , Bases de Dados Factuais , Feminino , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18 , Humanos , Razão de Chances , Vacinação/efeitos adversos
10.
Clin Rheumatol ; 34(7): 1225-31, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25535199

RESUMO

GARDASIL (Merck & Co., Inc., Whitehouse Station, NJ, USA) is a quadrivalent human papillomavirus (HPV4) vaccine. An epidemiological study was undertaken to evaluate concerns about the potential for HPV4 vaccination to induce serious autoimmune adverse events (SAAEs). The vaccine adverse event reporting system (VAERS) database was examined for adverse event reports associated with vaccines administered from January 2006 through December 2012 to recipients between 18 and 39 years old with a listed residence in the USA and a specified female gender. It was observed that cases with the SAAE outcomes of gastroenteritis (odds ratio (OR) = 4.6, 95% confidence interval (CI) = 1.3-18.5), arthritis (OR = 2.5, 95% CI = 1.4-4.3), systemic lupus erythematosus (OR = 5.3, 95% CI = 1.5-20.5), vasculitis (OR = 4, 95% CI = 1.01-16.4), alopecia (OR = 8.3, 95% CI = 4.5-15.9), or CNS conditions (OR = 1.8, 95% CI = 1.04-2.9) were significantly more likely than controls to have received HPV4 vaccine (median onset of SAAE symptoms from 6 to 55 days post-HPV4 vaccination). Cases with the outcomes of Guillain-Barre syndrome (OR = 0.75, 95% CI = 0.42-1.3) or thrombocytopenia (OR = 1.3, 95% CI = 0.48-3.5) were no more likely than controls to have received HPV4 vaccine. Cases with the general health outcomes of infection (OR = 0.72, 95% CI = 0.27-1.7), conjunctivitis (OR = 0.88, 95% CI = 0.29-2.7), or diarrhea (OR = 1.01, 95% CI = 0.83-1.22) were no more likely than controls to have received HPV4 vaccine. Previous case series of SAAEs and biological plausibility support the observed results. Additional studies should be conducted to further evaluate the potential biological mechanisms involved in HPV4 vaccine-associated SAAEs in animal model systems, and to examine the potential epidemiological relationship between HPV4 vaccine-associated SAAEs in other databases and populations.


Assuntos
Doenças Autoimunes/induzido quimicamente , Doenças Autoimunes/imunologia , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/efeitos adversos , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/efeitos adversos , Adolescente , Adulto , Sistemas de Notificação de Reações Adversas a Medicamentos , Estudos de Casos e Controles , Feminino , Síndrome de Guillain-Barré/etiologia , Humanos , Razão de Chances , Trombocitopenia/etiologia , Resultado do Tratamento , Vacinação/efeitos adversos , Adulto Jovem
11.
Neuro Endocrinol Lett ; 35(7): 537-52, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25617876

RESUMO

The purpose of this review is to examine the evidence for a relationship between mercury (Hg) exposure from dental amalgams and certain idiopathic chronic illnesses--chronic fatigue syndrome (CFS), fibromyalgia (FM), depression, anxiety, and suicide. Dental amalgam is a commonly used dental restorative material that contains approximately 50% elemental mercury (Hg0) by weight and releases Hg0 vapor. Studies have shown that chronic Hg exposure from various sources including dental amalgams is associated with numerous health complaints, including fatigue, anxiety, and depression--and these are among the main symptoms that are associated with CFS and FM. In addition, several studies have shown that the removal of amalgams is associated with improvement in these symptoms. Although the issue of amalgam safety is still under debate, the preponderance of evidence suggests that Hg exposure from dental amalgams may cause or contribute to many chronic conditions. Thus, consideration of Hg toxicity may be central to the effective clinical investigation of many chronic illnesses, particularly those involving fatigue and depression.


Assuntos
Ansiedade/etiologia , Amálgama Dentário/efeitos adversos , Depressão/etiologia , Fadiga/etiologia , Compostos de Mercúrio/efeitos adversos , Suicídio , Doença Crônica , Prática Clínica Baseada em Evidências , Fibromialgia/etiologia , Humanos
12.
Neurochem Res ; 38(11): 2336-41, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24005823

RESUMO

L-Carnitine is a naturally occurring substance required in mammalian energy metabolism that functions by facilitating long-chain fatty acid entry into cellular mitochondria, thereby delivering substrate for oxidation and subsequent energy production. It has been purposed that L-carnitine may improve and preserve cognitive performance, and may lead to better cognitive aging through the life span, and several controlled human clinical trials with L-carnitine support the hypothesis that this substance has the ability to improve cognitive function. We further hypothesized that, since L-carnitine is an important co-factor of mammalian mitochondrial energy metabolism, acute administration of L-carnitine to human tissue culture cells should result in detectable increases in mitochondrial function. Cultures of SH-SY-5Y human neuroblastoma and 1321N1 human astrocytoma cells grown in 96-well cell culture plates were acutely administered L-carnitine hydrochloride, and then, mitochondrial function was assayed using the colorimetric 2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxyanilide inner salt cell assay kit in a VERSAmax tunable microplate reader. Significant increases in mitochondrial function were observed when human neuroblastoma or human astrocytoma cells were exposed to 100 nM (20 µg L-carnitine hydrochloride/L) to 100 µM (20 mg L-carnitine hydrochloride/L) concentrations of L-carnitine hydrochloride in comparison to unexposed cells, whereas no significant positive effects were observed at lower or higher concentrations of L-carnitine hydrochloride. The results of the present study provide insights for how L-carnitine therapy may significantly improve human neuronal function, but we recommend that future studies further explore different derivatives of L-carnitine compounds in different in vitro cell-based systems using different markers of mitochondrial function.


Assuntos
Carnitina/farmacologia , Mitocôndrias/fisiologia , Cognição/efeitos dos fármacos , Humanos , Mitocôndrias/efeitos dos fármacos , Células Tumorais Cultivadas
13.
Int J Environ Res Public Health ; 10(8): 3771-800, 2013 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-23965928

RESUMO

Autism spectrum disorder (ASD) is a neurological disorder in which a significant number of the children experience a developmental regression characterized by a loss of previously acquired skills and abilities. Typically reported are losses of verbal, nonverbal, and social abilities. Several recent studies suggest that children diagnosed with an ASD have abnormal sulfation chemistry, limited thiol availability, and decreased glutathione (GSH) reserve capacity, resulting in a compromised oxidation/reduction (redox) and detoxification capacity. Research indicates that the availability of thiols, particularly GSH, can influence the effects of thimerosal (TM) and other mercury (Hg) compounds. TM is an organomercurial compound (49.55% Hg by weight) that has been, and continues to be, used as a preservative in many childhood vaccines, particularly in developing countries. Thiol-modulating mechanisms affecting the cytotoxicity of TM have been identified. Importantly, the emergence of ASD symptoms post-6 months of age temporally follows the administration of many childhood vaccines. The purpose of the present critical review is provide mechanistic insight regarding how limited thiol availability, abnormal sulfation chemistry, and decreased GSH reserve capacity in children with an ASD could make them more susceptible to the toxic effects of TM routinely administered as part of mandated childhood immunization schedules.


Assuntos
Transtornos Globais do Desenvolvimento Infantil/etiologia , Transtornos Globais do Desenvolvimento Infantil/metabolismo , Glutationa/metabolismo , Compostos de Sulfidrila/metabolismo , Timerosal/efeitos adversos , Timerosal/metabolismo , Animais , Criança , Transtornos Globais do Desenvolvimento Infantil/patologia , Humanos , Mercúrio/metabolismo , Oxirredução , Conservantes Farmacêuticos/efeitos adversos , Conservantes Farmacêuticos/metabolismo , Fatores de Risco , Vacinação , Vacinas
14.
Med Sci Monit ; 17(12): CR677-82, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22129897

RESUMO

BACKGROUND: Recent evidence shows that subjects diagnosed with an autism spectrum disorder (ASD) have significantly lower levels of glutathione than typically developing children. The purpose of this study was to examine the use of two commonly used glutathione supplements in subjects diagnosed with an ASD to determine their efficacy in increasing blood glutathione levels in subjects diagnosed with an ASD. MATERIAL/METHODS: The study was an eight-week, open-label trial using oral lipoceutical glutathione (n=13) or transdermal glutathione (n=13) in children, 3-13 years of age, with a diagnosis of an ASD. Subjects underwent pre- and post-treatment lab testing to evaluate plasma reduced glutathione, oxidized glutathione, cysteine, taurine, free and total sulfate, and whole-blood glutathione levels. RESULTS: The oral treatment group showed significant increases in plasma reduced glutathione, but not whole-blood glutathione levels following supplementation. Both the oral and transdermal treatment groups showed significant increases in plasma sulfate, cysteine, and taurine following supplementation. CONCLUSIONS: The results suggest that oral and transdermal glutathione supplementation may have some benefit in improving some of the transsulfuration metabolites. Future studies among subjects diagnosed with an ASD should further explore the pharmacokinetics of glutathione supplementation and evaluate the potential effects of glutathione supplementation upon clinical symptoms.


Assuntos
Transtornos Globais do Desenvolvimento Infantil/tratamento farmacológico , Suplementos Nutricionais , Glutationa/uso terapêutico , Adolescente , Criança , Transtornos Globais do Desenvolvimento Infantil/diagnóstico , Pré-Escolar , Feminino , Humanos , Masculino , Redes e Vias Metabólicas , Enxofre/metabolismo
15.
Acta Neurobiol Exp (Wars) ; 70(2): 209-26, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20628444

RESUMO

Autism spectrum disorders (ASDs) also known as pervasive developmental disorders (PDD) are a behaviorally defined group of neurodevelopmental disorders that are usually diagnosed in early childhood. ASDs disproportionately affect male children. Mercury (Hg) a heavy metal, is widespread and persistent in the environment. Mercury is a ubiquitous source of danger in fish, drugs, fungicides/herbicides, dental fillings, thermometers, and many other products. Elevated Hg concentrations may remain in the brain from several years to decades following exposure. This is important because investigators have long recognized that Hg is a neurodevelopmental poison; it can cause problems in neuronal cell migration and division, and can ultimately cause cell degeneration and death. Case-reports of patients have described developmental regressions with ASD symptoms following fetal and/or early childhood Hg exposure, and epidemiological studies have linked exposure to Hg with an elevated risk of a patient being diagnosed with an ASD. Immune, sensory, neurological, motor, and behavioral dysfunctions similar to traits defining or associated with ASDs were reported following Hg intoxication with similarities extending to neuroanatomy, neurotransmitters, and biochemistry. The sexual dimorphism of ASDs may result from synergistic neurotoxicity caused by the interaction of testosterone and Hg; in contrast, estrogen is protective, mitigating the toxicity of Hg. Mercury exposure may significantly increase androgen levels, and as a result, patients diagnosed with an ASD may significantly benefit from anti-androgen therapy. Finally, the clinical geneticist has a wealth of biomarkers to evaluate and treat patients diagnosed with an ASD.


Assuntos
Transtorno Autístico/induzido quimicamente , Transtorno Autístico/genética , Estradiol/fisiologia , Mercúrio/toxicidade , Testosterona/fisiologia , Timerosal/efeitos adversos , Transtorno Autístico/epidemiologia , Criança , Pré-Escolar , Exposição Ambiental/efeitos adversos , Feminino , Humanos , Lactente , Masculino , Intoxicação do Sistema Nervoso por Mercúrio/epidemiologia , Intoxicação do Sistema Nervoso por Mercúrio/genética , Compostos de Metilmercúrio/toxicidade
16.
Med Sci Monit ; 16(5): SR21-7, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20424565

RESUMO

BACKGROUND: In vaccines/biologics, preservatives are used to prevent microbial growth. MATERIAL/METHODS: The present study examined: (1) the comparative toxicities of commonly used preservatives in US licensed vaccines to human neurons; and (2) the relative toxicity index of these compounds to human neurons in comparison to bacterial cells. RESULTS: Using human neuroblastoma cells, the relative cytotoxicity of the levels of the compounds commonly used as preservative in US licensed vaccines was found to be phenol <2-phenoxyethanol < benzethonium chloride < Thimerosal. The observed relative toxicity indices (human neuroblastoma cells/bacterial cells) were 2-phenoxyethanol (4.6-fold) < phenol (12.2-fold) < Thimerosal (>330-fold). In addition, for the compounds tested, except for 2-phenoxyethanol, the concentrations necessary to induce significant killing of bacterial cells were significantly higher than those routinely present in US licensed vaccine/biological preparations. CONCLUSIONS: None of the compounds commonly used as preservatives in US licensed vaccine/biological preparations can be considered an ideal preservative, and their ability to fully comply with the requirements of the US Code of Federal Regulations (CFR) for preservatives is in doubt. Future formulations of US licensed vaccines/biologics should be produced in aseptic manufacturing plants as single dose preparations, eliminating the need for preservatives and an unnecessary risk to patients.


Assuntos
Produtos Biológicos/efeitos adversos , Conservantes Farmacêuticos/efeitos adversos , Vacinas/efeitos adversos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Humanos
17.
Neurochem Res ; 34(2): 386-93, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18612812

RESUMO

The goal of this study was to evaluate transsulfuration metabolites in participants diagnosed with autism spectrum disorders (ASDs). Transsulfuration metabolites, including: plasma reduced glutathione (GSH), plasma oxidized glutathione (GSSG), plasma cysteine, plasma taurine, plasma sulfate, and plasma free sulfate among participants diagnosed with ASDs (n = 38) in comparison to age-matched neurotypical controls were prospectively evaluated. Testing was conducted using Vitamin Diagnostics, Inc. (CLIA-approved). Participants diagnosed with ASDs had significantly (P < 0.001) decreased plasma reduced GSH, plasma cysteine, plasma taurine, plasma sulfate, and plasma free sulfate relative to controls. By contrast, participants diagnosed with ASDs had significantly (P < 0.001) increased plasma GSSG relative to controls. The present observations are compatible with increased oxidative stress and a decreased detoxification capacity, particularly of mercury, in patients diagnosed with ASDs. Patients diagnosed with ASDs should be routinely tested to evaluate transsulfuration metabolites, and potential treatment protocols should be evaluated to potentially correct the transsulfuration abnormalities observed.


Assuntos
Transtorno Autístico/sangue , Biomarcadores/sangue , Enxofre/metabolismo , Adolescente , Criança , Pré-Escolar , Cisteína/sangue , Feminino , Glutationa/sangue , Dissulfeto de Glutationa/sangue , Humanos , Masculino , Estudos Prospectivos , Sulfatos/sangue , Taurina/sangue
18.
J Neurol Sci ; 280(1-2): 101-8, 2009 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-18817931

RESUMO

Autism spectrum disorders (ASDs) may result from a combination of genetic/biochemical susceptibilities in the form of a reduced ability to excrete mercury and/or increased environmental exposure at key developmental times. Urinary porphyrins and transsulfuration metabolites in participants diagnosed with an ASD were examined. A prospective, blinded study was undertaken to evaluate a cohort of 28 participants with an ASD diagnosis for Childhood Autism Rating Scale (CARS) scores, urinary porphyrins, and transsulfuration metabolites. Testing was conducted using Vitamin Diagnostics, Inc. (CLIA-approved) and Laboratoire Philippe Auguste (ISO-approved). Participants with severe ASDs had significantly increased mercury intoxication-associated urinary porphyrins (pentacarboxyporphyrin, precoproporphyrin, and coproporphyrin) in comparison to participants with mild ASDs, whereas other urinary porphyrins were similar in both groups. Significantly decreased plasma levels of reduced glutathione (GSH), cysteine, and sulfate were observed among study participants relative to controls. In contrast, study participants had significantly increased plasma oxidized glutathione (GSSG) relative to controls. Mercury intoxication-associated urinary porphyrins were significantly correlated with increasing CARS scores and GSSG levels, whereas other urinary porphyrins did not show these relationships. The urinary porphyrin and CARS score correlations observed among study participants suggest that mercury intoxication is significantly associated with autistic symptoms. The transsulfuration abnormalities observed among study participants indicate that mercury intoxication was associated with increased oxidative stress and decreased detoxification capacity.


Assuntos
Transtorno Autístico/sangue , Transtorno Autístico/urina , Suscetibilidade a Doenças , Exposição Ambiental , Mercúrio , Adolescente , Biomarcadores/análise , Biomarcadores/sangue , Criança , Pré-Escolar , Estudos de Coortes , Cisteína/sangue , Feminino , Glutationa/sangue , Dissulfeto de Glutationa/sangue , Humanos , Masculino , Testes Neuropsicológicos , Projetos Piloto , Porfirinas/urina , Sulfatos/sangue
19.
Horm Res ; 66(4): 182-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16825783

RESUMO

BACKGROUND/AIMS: The prevalence of autism spectrum disorders (ASDs) is 1 in 300 children in the US. ASDs are characterized by impairments in social relatedness and communication, repetitive behaviors, abnormal movement patterns, and sensory dysfunction. Pre-pubertal age children with ASDs were assessed for metabolites in the methionine cycle-transsulfuration and androgen pathways, and for present physical development/behaviors indicative of hyperandrogenicity. METHODS: The Institutional Review Board of the Institute for Chronic Illnesses (Office for Human Research Protections, US Department of Health and Human Services IRB number: IRB00005375) approved the present study. Sixteen consecutive pre-pubertal age children (

Assuntos
Androgênios/sangue , Transtorno Autístico/sangue , Transtorno Autístico/epidemiologia , Metionina/metabolismo , Sulfurtransferases/metabolismo , Biomarcadores/sangue , Criança , Pré-Escolar , Cistationina/sangue , Cisteína/sangue , Desidroepiandrosterona/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Glutationa/sangue , Homocisteína/sangue , Humanos , Masculino , Metionina/sangue , Modelos Biológicos , Transdução de Sinais/fisiologia , Testosterona/sangue
20.
Med Hypotheses ; 64(5): 946-54, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15780490

RESUMO

Autism is a neurodevelopmental disorder that according to the Centers for Disease Control and Prevention (CDC) affects 1 in 150 children in the United States. Autism is characterized by impairments in social relatedness and communication, repetitive behaviors, abnormal movements, and sensory dysfunction. Recently emerging evidence suggests that mercury, especially from childhood vaccines, appears to be a factor in the development of the autistic disorders, and that autistic children have higher than normal body-burdens of mercury. In considering mercury toxicity, it has previously been shown that testosterone significantly potentates mercury toxicity, whereas estrogen is protective. Examination of autistic children has shown that the severity of autistic disorders correlates with the amount of testosterone present in the amniotic fluid, and an examination of a case-series of autistic children has shown that some have plasma testosterone levels that were significantly elevated in comparison neurotypical control children. A review of some of the current biomedical therapies for autistics, such as glutathione and cysteine, chelation, secretin, and growth hormone, suggests that they may in fact lower testosterone levels. We put forward the medical hypothesis that autistic disorders, in fact, represents a form of testosterone mercury toxicity, and based upon this observation, one can design novel treatments for autistics directed towards higher testosterone levels in autistic children. We suggest a series of experiments that need to be conducted in order to evaluate the exact mechanisms for mercury-testosterone toxicity, and various types of clinical manipulations that may be employed to control testosterone levels. It is hoped by devising therapies that address the steroid hormone pathways, in addition to the current treatments that successful lower heavy metal body-burdens of mercury, will work synergistically to improve clinical outcomes. In light of the fact that there are a number of other diseases that may have a chronic mercury toxicity component, such as Alzheimer's disease, heart disease, obesity, ALS, asthma, and other various forms of autoimmune disorders, it is imperative that further research should be conducted to understand mercury-testosterone toxicity.


Assuntos
Transtorno Autístico/tratamento farmacológico , Mercúrio/efeitos adversos , Testosterona/uso terapêutico , Transtorno Autístico/induzido quimicamente , Estudos de Casos e Controles , Humanos , Mercúrio/farmacocinética , Testosterona/antagonistas & inibidores , Testosterona/sangue
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