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1.
Curr Opin Urol ; 27(6): 516-518, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28795961

RESUMEN

PURPOSE OF REVIEW: Testosterone therapy has been advocated in the treatment of symptoms that may represent normal aging. We briefly review randomized clinical trials on the effects of testosterone therapy on sexual function. RECENT FINDINGS: About half of clinical trials showed no benefit of testosterone therapy on any aspect of sexual function. In those studies showing a benefit on some aspect of sexual function, most sexual function domains were not improved. Testosterone therapy has been disappointing in the treatment of erectile dysfunction. Potential risks of therapy include an increase in thromboembolic and other cardiovascular diseases. SUMMARY: The limited and inconsistent benefits of testosterone therapy for sexual function argue against use of this therapy in aging men, including those with 'low testosterone'.


Asunto(s)
Envejecimiento/fisiología , Disfunción Eréctil/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto , Disfunciones Sexuales Fisiológicas/tratamiento farmacológico , Testosterona/uso terapéutico , Anciano , Enfermedades Cardiovasculares , Humanos , Hipogonadismo , Masculino , Resultado del Tratamiento
2.
Regul Toxicol Pharmacol ; 90: 51-71, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28838609

RESUMEN

A quantitative weight of evidence (QWoE) methodology was developed to assess confidence in postulated mode(s) of action for adverse effects in animal toxicity studies. The QWoE is appropriate for assessing adverse effects as relevant endpoints for classification and labeling purposes. The methodology involves definition of mode of actions and scoring supporting data for all key steps using predefined criteria for quality and relevance/strength of effects. Scores for all key steps are summarized, and the summary score is compared to the maximal achievable score for the mode of action. The ratio of the summary score to the maximal achievable scores gives an indication of confidence in a specific mode of action in animals. The mode of action in animals with highest confidence is then taken forward to assess appropriateness to humans. If one of the key steps cannot occur in humans, the mode of action is not relevant to humans. The methodology developed is applied to four case studies.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Modelos Animales , Fenómenos Farmacológicos , Pruebas de Toxicidad/métodos , Animales , Área Bajo la Curva , Humanos , Especificidad de la Especie
3.
Regul Toxicol Pharmacol ; 74 Suppl: S44-56, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26148665

RESUMEN

Decamethylcyclopentasiloxane (D5) is a cyclic siloxane used in the production and formulation of consumer products with potential exposure to manufacturing workers, consumer, and the general public. Following a combined 2-year inhalation chronic bioassay performed in Fischer 344 (F344) rats, an increase in uterine endometrial adenocarcinomas was noted at the highest concentration to which animals were exposed. No other neoplasms were detected. In this study, a dose of 160 ppm produced an incidence of 8% endometrial adenocarcinomas. Based on a number of experimental studies with D5, the current manuscript examines the biological relevance and possible modes of action for the uterine endometrial adenocarcinomas observed in the rat following chronic exposure to D5. Variable rates of spontaneous uterine endometrial adenocarcinomas have been reported for untreated F344 CrlBr rats. As such, we concluded that the slight increase in uterine endometrial adenocarcinomas observed in the D5 chronic bioassay might not be the result of D5 exposure but may be related to variability of the spontaneous tumor incidence in this strain of rat. However, if the uterine endometrial adenocarcinomas are related to D5-exposure, alteration in the estrous cycle in the aging F344 rat is the most likely mode of action. D5 is not genotoxic or estrogenic. The alteration in the estrous cycle is caused by a decrease in progesterone with an increase in the estrogen:progesterone ratio most likely induced by a decrease in prolactin concentration. Available data support that exposure to D5 influences prolactin concentration. Although the effects on prolactin concentrations in a number of experiments were not always consistent, the available data support the conclusion that D5 is acting via a dopamine receptor agonist-like mechanism to alter the pituitary control of the estrous cycle. In further support of this mode of action, studies in F344 aged animals showed that the effects of D5 on estrous cyclicity produced a response consistent with a dopamine-like effect and further suggest that D5 is accelerating the aging of the reproductive endocrine system in the F344 rat utilized in this study. This mode of action for uterine endometrial adenocarcinoma tumorigenesis is not relevant for humans.


Asunto(s)
Adenocarcinoma/inducido químicamente , Neoplasias Endometriales/inducido químicamente , Siloxanos/toxicidad , Administración por Inhalación , Envejecimiento , Animales , Pruebas de Carcinogenicidad , Ciclo Estral , Femenino , Humanos , Masculino , Ratas , Ratas Endogámicas F344 , Medición de Riesgo , Especificidad de la Especie , Pruebas de Toxicidad Crónica
4.
Regul Toxicol Pharmacol ; 74 Suppl: S57-66, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26184430

RESUMEN

Decamethylcyclopentasiloxane (D5) is a cyclic polydimethylsiloxane used in the synthesis of silicon-based materials and as a component in consumer products. Male and female Fischer 344 rats were exposed to D5 vapor (0, 10, 40, 160 ppm; whole-body inhalation) for 6 h/d, 5 d/wk, for up to 104 weeks. Microscopic examination of tissues revealed test article effects at 160 ppm in the upper respiratory tract (hyaline inclusions in males and females at 6, 12, and 24 months) and an increased incidence of uterine endometrial adenocarcinoma at 24-months. The hyaline inclusions were considered a non-adverse tissue response for lack of any other respiratory tract non-neoplastic or neoplastic changes. Uterine endometrial adenocarcinoma was not anticipated. Toxicity testing (mutagenicity/genotoxicity, acute, sub-acute and sub-chronic descriptive toxicity) performed prior to the conduct of the chronic bioassay provided no indication that the uterus was a potential target organ. The target organ and tumor type specificity (adenocarcinoma is a common spontaneous tumor in the aged Fischer 344 rat) suggests the effect is associated with estrous cycle alteration. A robust assessment of potential mode(s) of action responsible for the uterine tumors and relevance to humans is addressed in a companion manuscript (Klaunig et al., 2015).


Asunto(s)
Adenocarcinoma/inducido químicamente , Neoplasias Endometriales/inducido químicamente , Siloxanos/toxicidad , Adenocarcinoma/patología , Administración por Inhalación , Animales , Pruebas de Carcinogenicidad , Neoplasias Endometriales/patología , Endometrio/efectos de los fármacos , Endometrio/patología , Femenino , Masculino , Ratas Endogámicas F344 , Sistema Respiratorio/efectos de los fármacos , Sistema Respiratorio/patología , Siloxanos/farmacocinética , Especificidad de la Especie , Pruebas de Toxicidad Crónica
5.
Birth Defects Res B Dev Reprod Toxicol ; 104(3): 129-39, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26195119

RESUMEN

Agent Orange was sprayed in parts of southern Vietnam during the U.S.-Vietnam war and was a mixture of two chlorophenoxy herbicides. The mixture was contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). TCDD and other dioxins and furans are measurable in the milk of Vietnamese women. We explored whether the TCDD in milk from these women was from Agent Orange and whether lactational exposure can be a mode of transgenerational effects of TCDD from Agent Orange. A review of the world's literature on milk concentrations of polychlorinated compounds showed the presence of TCDD and other dioxins and furans in all countries that have been assessed. The congener profile of these chemicals, that is, the proportion of different congeners in the sample, can be used to assess the source of milk contamination. Measurements in most countries, including contemporary measurements in Vietnam, are consistent with non-Agent Orange exposure sources, including industrial activities and incineration of waste. Models and supporting human data suggest that TCDD from breastfeeding does not persist in a child past adolescence and that the adult body burden of TCDD is independent of whether the individual was breast- or bottle-fed as a child. These findings suggest that exposure to Agent Orange in Vietnam did not result in persistent transgenerational exposure through human milk.


Asunto(s)
Ácido 2,4,5-Triclorofenoxiacético/análisis , Ácido 2,4-Diclorofenoxiacético/análisis , Exposición a Riesgos Ambientales/análisis , Contaminantes Ambientales/análisis , Leche Humana/química , Dibenzodioxinas Policloradas/análisis , Ácido 2,4,5-Triclorofenoxiacético/química , Ácido 2,4,5-Triclorofenoxiacético/farmacocinética , Ácido 2,4-Diclorofenoxiacético/química , Ácido 2,4-Diclorofenoxiacético/farmacocinética , Adulto , Agente Naranja , Contaminantes Ambientales/química , Femenino , Humanos , Lactante , Dibenzodioxinas Policloradas/química , Dibenzodioxinas Policloradas/farmacocinética , Vietnam
7.
Birth Defects Res B Dev Reprod Toxicol ; 101(3): 199-214, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24797531

RESUMEN

Atrazine (ATR), hydroxyatrazine (OH-ATR), and the three chloro metabolites of ATR (deethylatrazine [DEA], deisopropylatrazine [DIA], diaminochlorotriazine [DACT]) were evaluated for developmental effects in rats and rabbits. Three developmental toxicity studies were conducted on ATR in rats (two studies) and rabbits and a developmental toxicity study was conducted in rats for each of the four ATR metabolites DEA, DIA, DACT, and OH-ATZ. ATR administration by gavage to pregnant rats and rabbits from implantation (gestation day [GD] 6 in rat, GD 7 in rabbit) through closure of the palate (GD 15 in rat and GD 19 in rabbit) did not statistically significantly alter the incidence of developmental abnormalities or malformations at dose levels up to 100 (rat) or 75 (rabbit) mg/kg bw/day. There were no effects on developmental toxicity parameters for DEA, DIA, DACT, or OH-ATR at oral dose levels up to 100, 100, 150, or 125 mg/kg bw/day, respectively, with the exception of reductions in fetal body weight by DACT and OH-ATR in the presence of decreased maternal body weight gain. ATR did not adversely affect developmental end points in a two-generation study conducted in rats exposed to dose levels up to 500 ppm (38.7 mg/kg/day) in the diet. The 500-ppm dose level resulted in significantly reduced maternal body weight gain. Overall, data show that neither ATR nor its metabolites statistically significantly affected rat or rabbit embryo-fetal development even at dose levels producing maternal toxicity.


Asunto(s)
Atrazina/análogos & derivados , Atrazina/toxicidad , Animales , Atrazina/administración & dosificación , Relación Dosis-Respuesta a Droga , Femenino , Peso Fetal/efectos de los fármacos , Feto/efectos de los fármacos , Herbicidas/administración & dosificación , Herbicidas/toxicidad , Exposición Materna/efectos adversos , Embarazo , Conejos , Ratas , Pruebas de Toxicidad
8.
Birth Defects Res B Dev Reprod Toxicol ; 101(3): 215-36, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24797711

RESUMEN

Atrazine (ATR) is a commonly used agricultural herbicide that has been the subject of epidemiologic studies assessing its relation to reproductive health problems. This review evaluates both the consistency and the quality of epidemiologic evidence testing the hypothesis that ATR exposure, at usually encountered levels, is a risk factor for birth defects, small for gestational age birth weight, prematurity, miscarriages, and problems of fetal growth and development. We followed the current methodological guidelines for systematic reviews by using two independent researchers to identify, retrieve, and evaluate the relevant epidemiologic literature on the relation of ATR to various adverse outcomes of birth and pregnancy. Each eligible paper was summarized with respect to its methods and results with particular attention to study design and exposure assessment, which have been cited as the main areas of weakness in ATR research. As a quantitative meta-analysis was not feasible, the study results were categorized qualitatively as positive, null, or mixed. The literature on ATR and pregnancy-related health outcomes is growing rapidly, but the quality of the data is poor with most papers using aggregate rather than individual-level information. Without good quality data, the results are difficult to assess; however, it is worth noting that none of the outcome categories demonstrated consistent positive associations across studies. Considering the poor quality of the data and the lack of robust findings across studies, conclusions about a causal link between ATR and adverse pregnancy outcomes are not warranted.


Asunto(s)
Atrazina/toxicidad , Resultado del Embarazo , Aborto Espontáneo/inducido químicamente , Aborto Espontáneo/patología , Animales , Peso al Nacer/efectos de los fármacos , Modelos Animales de Enfermedad , Femenino , Desarrollo Fetal/efectos de los fármacos , Edad Gestacional , Herbicidas/toxicidad , Humanos , Exposición Materna/efectos adversos , Embarazo
9.
Birth Defects Res B Dev Reprod Toxicol ; 101(3): 237-53, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24797874

RESUMEN

BACKGROUND: Reproductive toxicity of Atrazine (ATR) was evaluated in two rat multigenerational studies. Development of male reproductive parameters was evaluated in separate studies after prenatal or postnatal exposure. METHODS: In multigenerational studies, rats received dietary concentrations of 0, 10, 50, 100 or 500 ppm ATR. In separate studies in female rats, ATR was administered by gavage at 0, 1, 5, 25 or 125 mg/kg/day during pregnancy (GD6-21) or lactation (LD2-21). Plasma testosterone concentration, testicular and epididymal weights, and sperm counts were measured in male offspring on PND70 and 170. RESULTS: In the multigenerational studies, parental systemic toxicity occurred at 500 ppm (38.7 mg/kg/day), but reproductive endpoints were unaffected. In the prenatal study, maternal toxicity and embryo-fetal mortality occurred at 125 mg/kg/day. In male offspring, testosterone levels and sperm counts were unaffected, although the percentage of abnormal sperm increased at 125 mg/kg/day (PND 70) and 25 mg/kg/day (PND170). In the postnatal study, maternal toxicity and reduced body weights of male offspring occurred at 125 mg/kg/day. Additionally, reduced testicular (PND70, PND170) and epididymal (PND70) weights and increased numbers of abnormal sperm (PND70, PND170) were seen, but no changes in plasma testosterone or sperm counts. CONCLUSIONS: Dietary administration of ATR did not affect rat reproduction up to a parentally toxic dose of 38.7 mg/kg/day. Some effects on male reproductive system development occurred after high dose, bolus administration to dams, but doses were much higher than expected under normal use conditions. Thus, oral RfDs for ATR would be protective for reproductive effects.


Asunto(s)
Atrazina/toxicidad , Reproducción/efectos de los fármacos , Administración Oral , Animales , Atrazina/administración & dosificación , Peso Corporal , Relación Dosis-Respuesta a Droga , Determinación de Punto Final , Epidídimo/efectos de los fármacos , Epidídimo/metabolismo , Femenino , Lactancia , Masculino , Exposición Materna , Nivel sin Efectos Adversos Observados , Tamaño de los Órganos/efectos de los fármacos , Embarazo , Ratas , Espermatozoides/efectos de los fármacos , Testosterona/sangre
10.
Birth Defects Res B Dev Reprod Toxicol ; 101(6): 423-8, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25475026

RESUMEN

Validation of alternative assays requires comparison of the responses to toxicants in the alternative assay with in vivo responses. Chemicals have been classified as "positive" or "negative" in vivo, despite the fact that developmental toxicity is conditional on magnitude of exposure. We developed a list of positive and negative developmental exposures, with exposure defined by toxicokinetic data, specifically maternal plasma Cmax . We selected a series of 20 chemicals that caused developmental toxicity and for which there were appropriate toxicokinetic data. Where possible, we used the same chemical for both positive and negative exposures, the positive being the Cmax at a dose level that produced significant teratogenicity or embryolethality, the negative being the Cmax at a dose level not causing developmental toxicity. It was not possible to find toxicokinetic data at the no-effect level for all positive compounds, and the negative exposure list contains Cmax values for some compounds that do not have developmental toxicity up to the highest dose level tested. This exposure-based reference list represents a fundamentally different approach to the evaluation of alternative tests and is proposed as a step toward application of alternative tests in quantitative risk assessment.


Asunto(s)
Desarrollo Fetal/efectos de los fármacos , Teratogénesis/efectos de los fármacos , Teratógenos/toxicidad , Pruebas de Toxicidad , Bioensayo , Ensayos Analíticos de Alto Rendimiento , Técnicas In Vitro , Medición de Riesgo
11.
J Med Ethics ; 39(2): 110-4, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23015747

RESUMEN

The use of a placebo arm in clinical trials is unethical if there is an active comparator that is acceptably safe and effective. We argue that reasonable evidence of effectiveness and safety of an inexpensive alternative to an expensive therapy is sufficient to require that the inexpensive therapy be included as a comparator when the expensive therapy is tested, and that use of an inactive placebo comparator only is not ethical. For example, studies of the expensive drug eplerenone for congestive heart failure have not included a spironolactone arm, although there is reasonable evidence that spironolactone would be safe and effective, and spironolactone is inexpensive. The requirement to study inexpensive therapies is based on avoidance of unnecessary cost in medical care as an example of non-maleficence. Several ethical actors in the design, conduct, and publication of clinical trials and their results bear responsibility for the appropriate conduct of clinical trials. That responsibility includes protecting study subjects from being asked to participate in clinical trials that serve primarily to promote the use of new and expensive therapies.


Asunto(s)
Ensayos Clínicos como Asunto/ética , Costos de los Medicamentos , Insuficiencia Cardíaca/tratamiento farmacológico , Antagonistas de Receptores de Mineralocorticoides/economía , Placebos , Espironolactona/análogos & derivados , Espironolactona/economía , Análisis Costo-Beneficio , Costos de los Medicamentos/ética , Eplerenona , Comités de Ética en Investigación , Ética en Investigación , Insuficiencia Cardíaca/diagnóstico , Humanos , Antagonistas de Receptores de Mineralocorticoides/uso terapéutico , Publicaciones Periódicas como Asunto , Investigadores , Índice de Severidad de la Enfermedad , Espironolactona/uso terapéutico , Equipoise Terapéutico , Resultado del Tratamiento , Estados Unidos , United States Food and Drug Administration
12.
Drug Saf ; 46(3): 297-308, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36682012

RESUMEN

INTRODUCTION: The advent of the coronavirus disease 2019 (COVID-19) pandemic has led to the development of vaccines against severe acute respiratory syndrome coronavirus 2. Prospective evidence regarding safety for pregnant people and their developing fetuses is lacking. The aim of the COVID-19 Vaccines International Pregnancy Exposure Registry (C-VIPER) is to estimate the relative risk of obstetric, neonatal, and infant outcomes by comparing participants vaccinated against COVID-19 during pregnancy to a reference group of people enrolled in the Pregistry International Pregnancy Exposure Registry (PIPER) who remained unvaccinated during pregnancy. METHODS: The C-VIPER and the PIPER are international, non-interventional, real-world cohort studies. Participants receiving a COVID-19 vaccine during pregnancy will be matched in the analyses by country and gestational age at enrollment to unvaccinated individuals. Self-enrolled and self-consented participants complete online questionnaires at enrollment, during pregnancy, and for 12 months after the delivery of a live infant. Where possible, outcomes are verified by medical records. The study aims to recruit at least 500 pregnancies for each approved or authorized vaccine and will last for 5 years for each product. CONCLUSIONS: By collecting data for each vaccine brand, the C-VIPER will be able to determine individual safety profiles. The study design allows for analysis of the effects of exposure to COVID-19 vaccines during specific etiologically relevant periods of gestation. Although the sample size may be too small to detect associations with rare outcomes, the study will be used to generate hypotheses for future research. Ultimately, the C-VIPER should provide data that will allow pregnant people and their healthcare providers to make informed decisions about COVID-19 vaccination. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov NCT04705116. Registered on 12 January, 2021. EU PAS EUPAS39096. Registered on 20 January, 2021.


Asunto(s)
COVID-19 , Vacunas , Embarazo , Femenino , Recién Nacido , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , Vacunas contra la COVID-19/efectos adversos , Estudios Prospectivos , Resultado del Tratamiento
13.
Birth Defects Res A Clin Mol Teratol ; 94(4): 187-207, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22434686

RESUMEN

Methotrexate and aminopterin are folic acid antagonists that inhibit dihydrofolate reductase, resulting in a block in the synthesis of thymidine and inhibition of DNA synthesis. Methotrexate has been used for the treatment of malignancy, rheumatic disorders, and psoriasis and termination of intrauterine pregnancy. Recently, methotrexate has become a standard treatment for ectopic pregnancy. The misdiagnosis of an intrauterine pregnancy as an ectopic pregnancy can result in exposure of a continuing pregnancy to dose levels of methotrexate of 50 mg/m(2) (maternal body surface area). Experimental animal studies have associated methotrexate therapy with embryo death in mice, rats, rabbits, and monkeys. Structural malformations have been most consistently produced in rabbits at a maternal dose level of 19.2 mg/kg. Abnormalities in rabbits include hydrocephalus, microphthalmia, cleft lip and palate, micrognathia, dysplastic sacral and caudal vertebrate, phocomelia, hemimelia, syndactyly, and ectrodactyly. Based on human case reports of methotrexate exposure during pregnancy, a methotrexate embryopathy has been described that includes growth deficiency, microcephaly, hypoplasia of skull bones, wide fontanels, coronal or lambdoidal craniosynostosis, upswept frontal scalp hair, broad nasal bridge, shallow supraorbital ridges, prominent eyes, low-set ears, maxillary hypoplasia, epicanthal folds, short limbs, talipes, hypodactyly, and syndactyly. This syndrome may be associated with exposures between 6 and 8 weeks after conception and dose levels of 10 mg/week or greater. More recent case reports of methotrexate exposure for the misdiagnosis of ectopic pregnancy involve treatment before 6 weeks after conception and have raised the suggestion of a distinct syndrome due to such early exposures. Tetralogy of Fallot and perhaps other neural crest cell-related abnormalities may be features of this early syndrome. A disproportionality analysis of methotrexate and aminopterin case reports and series provides support for pulmonary atresia, craniosynostosis, and limb deficiencies as reported more often than expected in methotrexate-exposed children. Denominator-based data will be welcome to better define elements of a methotrexate embryopathy and possibly to distinguish an early exposure syndrome from anomalies traditionally associated with methotrexate exposure.


Asunto(s)
Anomalías Inducidas por Medicamentos/etiología , Anomalías Múltiples/inducido químicamente , Metotrexato/toxicidad , Teratógenos/toxicidad , Anomalías Inducidas por Medicamentos/patología , Anomalías Múltiples/patología , Aminopterina/toxicidad , Animales , Femenino , Enfermedades Fetales/etiología , Antagonistas del Ácido Fólico/toxicidad , Humanos , Ratones , Ratones Endogámicos C57BL , Embarazo , Complicaciones del Embarazo/tratamiento farmacológico , Embarazo Ectópico/tratamiento farmacológico , Conejos , Ratas , Ratas Sprague-Dawley , Tetrahidrofolato Deshidrogenasa/efectos de los fármacos
14.
Birth Defects Res A Clin Mol Teratol ; 94(9): 677-82, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22903940

RESUMEN

Iodine deficiency is an important nutritional deficiency, with more than 2 billion people worldwide estimated to be at risk. The developing fetus and young children are particularly at risk. During pregnancy and lactation, iodine requirements increase, whether in iodine-poor or iodine-sufficient countries, making the mother and the developing fetus vulnerable. The American Thyroid Association (ATA) recommends 250 micrograms per day of iodine intake for pregnant and lactating women. The thyroid gland is able to adapt to the changes associated with pregnancy as long as sufficient iodine is present. Dietary intake is the sole source of iodine, which is essential to the synthesis of thyroid hormones. Iodine is found in multiple dietary sources including iodized salt, dairy products, seaweed, and fish. Prenatal vitamins containing iodine are a good source of iodine, but iodine content in multivitamin supplements is highly variable. Congenital hypothyroidism is associated with cretinism. Clinical hypothyroidism has been associated with increased risk of poor perinatal outcome including prematurity, low birth weight, miscarriage, preeclampsia, fetal death, and impaired fetal neurocognitive development. Subclinical hypothyroidism is also associated with poor pregnancy outcomes and potential fetal neurocognitive deficits, but the data are more variable than those for clinical hypothyroidism. We concur with the ATA recommendation that all pregnant and lactating women should ingest (through diet and supplements) 250 micrograms of iodine daily. To achieve this goal, we recommend that all pregnant and lactating women take daily iodine supplementation of 150 micrograms.


Asunto(s)
Hipotiroidismo Congénito/prevención & control , Suplementos Dietéticos/provisión & distribución , Yodo/deficiencia , Animales , Hipotiroidismo Congénito/metabolismo , Suplementos Dietéticos/normas , Femenino , Peces , Humanos , Yodo/administración & dosificación , Yodo/metabolismo , Desnutrición , Necesidades Nutricionales/fisiología , Embarazo , Algas Marinas , Cloruro de Sodio Dietético/administración & dosificación , Teratología , Glándula Tiroides/efectos de los fármacos , Glándula Tiroides/metabolismo , Hormonas Tiroideas/biosíntesis , Vitaminas
16.
Regul Toxicol Pharmacol ; 62(1): 160-82, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22019814

RESUMEN

In the absence of toxicological data on a chemical, the threshold of toxicological concern (TTC) approach provides a system to estimate a conservative exposure below which there is a low probability of risk for adverse health effects. The original toxicology dataset underlying the TTC was based on NOELs from repeat dose studies. Subsequently there have been several efforts to assess whether or not these limits are also protective for reproductive/developmental effects. This work expands the database of chemicals with reproductive and developmental data, presents these data in a comprehensive and transparent format and groups the chemicals according to the TTC "Cramer Class" rules. Distributions of NOAELs from each of these classes were used to assess whether the previously proposed TTC values based on repeat dose data are protective for reproductive/developmental toxicity endpoints as well. The present analysis indicates that, for each Cramer Class, the reproductive and developmental endpoints would be protected at the corresponding general TTC tiers derived by Munro et al. (1996).


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Desarrollo Embrionario/efectos de los fármacos , Desarrollo Fetal/efectos de los fármacos , Sustancias Peligrosas/toxicidad , Reproducción/efectos de los fármacos , Animales , Relación Dosis-Respuesta a Droga , Humanos , Nivel sin Efectos Adversos Observados , Medición de Riesgo , Pruebas de Toxicidad
17.
Vaccines (Basel) ; 10(10)2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36298442

RESUMEN

This US-based, prospective observational cohort study evaluated the safety of a quadrivalent inactivated influenza vaccine (IIV4; Afluria Quadrivalent) in pregnant persons immunized over four influenza seasons between 2017 and 2021. Pregnancy outcomes included live birth, stillbirth, spontaneous abortion, and elective termination. Infant events of interest were major congenital malformations (MCMs), preterm birth (<37 weeks gestational age), and low birth weight (LBW). Data were descriptive; prevalence point estimates were reported with 95% confidence intervals (CI). A total of 483 pregnant persons were given IIV4 and evaluated; 477 (98.8%) reported a live birth, and there were 2 stillbirths, 4 spontaneous abortions, and no elective terminations or maternal deaths. The prevalence rates of infant events were as follows: preterm birth, 7.2% (upper 95% CI, 9.6%); LBW, 5.4% (upper 95% CI, 7.4%); and MCMs, 0.8% (upper 95% CI, 1.9%). Point estimates and upper 95% CIs of the observed prevalence rates were lower than or similar to background prevalence in the general US population. Our findings suggest no evidence of a safety concern with vaccinating this group at high risk of influenza complications and are consistent with published data from databases and surveillance systems that monitor the safety of influenza vaccines in pregnant persons.

18.
Vaccines (Basel) ; 10(10)2022 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-36298465

RESUMEN

Objective: To evaluate pregnancy and infant outcomes among persons immunized with a cell-based quadrivalent inactivated influenza vaccine (IIV4c) during routine pregnancy care. Design: Prospective observational cohort. Setting: US-based obstetrics/gynecology clinics. Population: Pregnant persons. This US-based, prospective observational cohort study evaluated the safety of quadrivalent inactivated influenza vaccine (IIV4c; Flucelvax® Quad) in pregnant persons immunized over 3 influenza seasons between 2017 and 2020. Pregnant persons were immunized with IIV4c as part of routine care, after which their health care provides HCPs with all observational data to a single coordinating center. Follow-up data were collected at the end of the second trimester and/or at the time of pregnancy outcome. A scientific advisory committee reviewed the data. Prevalence point estimates were reported with 95% confidence intervals (CIs). Pregnancy outcomes included: live birth, stillbirth, spontaneous abortion, elective termination, and maternal death. Infant outcomes included: preterm birth (<37 weeks gestational age), low birth weight (<2500 g), or major congenital malformations (MCMs). Of the 665 evaluable participants, 659 (99.1%) had a live birth. No stillbirths (0% [95% CI 0.0−0.6]), 4 spontaneous abortions (1.9% [0.5−4.8]), and 1 elective termination (0.5% [0.0−2.6]) were reported. Among 673 infants, 9.2% (upper 95% CI 11.5%) were born prematurely, 5.8% (upper 95% CI 7.6%) had low birth weight, and 1.9% (upper 95% CI 3.1%) were reported to have an MCM. No maternal deaths were reported. Of the 2 infants who died shortly after birth, one was adjudicated as not related to the vaccine; the other's cause could not be determined due to maternal loss to follow-up. The prevalence of adverse pregnancy outcomes or preterm birth, low birth weight, or MCMs in newborns was similar in persons vaccinated with IIV4c compared to the rates observed in US surveillance systems. The safety profile of IIV4c in pregnant persons is consistent with previously studied influenza vaccines.

19.
PLoS Med ; 8(3): e1000425, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21423581

RESUMEN

BACKGROUND: Even after the Women's Health Initiative (WHI) found that the risks of menopausal hormone therapy (hormone therapy) outweighed benefit for asymptomatic women, about half of gynecologists in the United States continued to believe that hormones benefited women's health. The pharmaceutical industry has supported publication of articles in medical journals for marketing purposes. It is unknown whether author relationships with industry affect promotional tone in articles on hormone therapy. The goal of this study was to determine whether promotional tone could be identified in narrative review articles regarding menopausal hormone therapy and whether articles identified as promotional were more likely to have been authored by those with conflicts of interest with manufacturers of menopausal hormone therapy. METHODS AND FINDINGS: We analyzed tone in opinion pieces on hormone therapy published in the four years after the estrogen-progestin arm of the WHI was stopped. First, we identified the ten authors with four or more MEDLINE-indexed reviews, editorials, comments, or letters on hormone replacement therapy or menopausal hormone therapy published between July 2002 and June 2006. Next, we conducted an additional search using the names of these authors to identify other relevant articles. Finally, after author names and affiliations were removed, 50 articles were evaluated by three readers for scientific accuracy and for tone. Scientific accuracy was assessed based on whether or not the findings of the WHI were accurately reported using two criteria: (1) Acknowledgment or lack of denial of the risk of breast cancer diagnosis associated with hormone therapy, and (2) acknowledgment that hormone therapy did not benefit cardiovascular disease endpoints. Determination of promotional tone was based on the assessment by each reader of whether the article appeared to promote hormone therapy. Analysis of inter-rater consistency found moderate agreement for scientific accuracy (κ=0.57) and substantial agreement for promotional tone (κ=0.65). After discussion, readers found 86% of the articles to be scientifically accurate and 64% to be promotional in tone. Themes that were common in articles considered promotional included attacks on the methodology of the WHI, arguments that clinical trial results should not guide treatment for individuals, and arguments that observational studies are as good as or better than randomized clinical trials for guiding clinical decisions. The promotional articles we identified also implied that the risks associated with hormone therapy have been exaggerated and that the benefits of hormone therapy have been or will be proven. Of the ten authors studied, eight were found to have declared payment for speaking or consulting on behalf of menopausal hormone manufacturers or for research support (seven of these eight were speakers or consultants). Thirty of 32 articles (90%) evaluated as promoting hormone therapy were authored by those with potential financial conflicts of interest, compared to 11 of 18 articles (61%) by those without such conflicts (p=0.0025). Articles promoting the use of menopausal hormone therapy were 2.41 times (95% confidence interval 1.49-4.93) as likely to have been authored by authors with conflicts of interest as by authors without conflicts of interest. In articles from three authors with conflicts of interest some of the same text was repeated word-for-word in different articles. CONCLUSION: There may be a connection between receiving industry funding for speaking, consulting, or research and the publication of promotional opinion pieces on menopausal hormone therapy.


Asunto(s)
Actitud del Personal de Salud , Conflicto de Intereses , Terapia de Reemplazo de Estrógeno/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto , Adulto , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/epidemiología , Enfermedades Cardiovasculares/epidemiología , Terapia de Reemplazo de Estrógeno/tendencias , Femenino , Humanos , Menopausia , Médicos/psicología , Literatura de Revisión como Asunto , Estados Unidos/epidemiología , Salud de la Mujer
20.
Am J Med Genet C Semin Med Genet ; 157C(3): 150-69, 2011 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-21766437

RESUMEN

A consideration of teratogenic exposures includes not only an agent (chemical, radiation, biologic) but an exposure level and timing of exposure. There are criteria by which exposures are evaluated for a causal connection with an abnormal outcome. We here review some teratogenic exposures and discuss how they were initially described and confirmed. We have limited our discussion to some of the exposures for which a connection to structural malformations has been accepted in some quarters, and we indicate some exposures for which a causal association awaits confirmation. We recommend that counselors find a reliable and updatable source of information on exposures during pregnancy.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Exposición a Riesgos Ambientales/efectos adversos , Teratógenos/toxicidad , Anomalías Inducidas por Medicamentos/etiología , Animales , Femenino , Humanos , Exposición Materna/efectos adversos , Embarazo , Complicaciones Infecciosas del Embarazo , Trastornos Relacionados con Sustancias/complicaciones
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