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1.
J Prev Alzheimers Dis ; 10(4): 765-770, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37874098

RESUMO

Aducanumab is the first FDA-approved amyloid-lowering immunotherapy for Alzheimer's disease. There is little real-world data to guide management of amyloid-related imaging abnormalities (ARIA), a potentially serious side-effect which requires surveillance with magnetic resonance imaging. We report our experiences in managing ARIA in patients receiving aducanumab at the Butler Hospital Memory and Aging Program during the year following FDA approval. We followed the Appropriate Use Recommendations for aducanumab to guide patient selection, detection, and management of ARIA (1). ARIA-E occurred in 6 out of 24 participants treated; all APOE-ε4 carriers. Treatment was discontinued in 4 cases of moderate-severe ARIA-E, temporarily held in 1 moderate case, and dosed through in 1 mild case (mean duration = 3 months, range, 1-6 months). No participants required hospitalization or high dose corticosteroids. Participants on anticoagulation were excluded and no macrohemorrhages occurred. These data support the measured approaches to treatment outlined in the Appropriate Use Recommendations.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Anticorpos Monoclonais Humanizados/efeitos adversos , Amiloide , Imageamento por Ressonância Magnética
2.
Sci Rep ; 13(1): 7613, 2023 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-37165038

RESUMO

Intraspecific interactions within predator populations can affect predator-prey dynamics and community structure, highlighting the need to better understand how these interactions respond to anthropogenic change. To this end, we used a half-century (1969-2018) of abundance and size-at-age data from Lake Erie's walleye (Sander vitreus) population to determine how anthropogenic alterations have influenced intraspecific interactions. Before the 1980s, the length-at-age of younger walleye (ages 1 and 2) negatively correlated with older (age 3 +) walleye abundance, signaling a 'density feedback' in which intraspecific competition limited growth. However, after the early 1980s this signal of intraspecific competition disappeared. This decoupling of the density feedback was related to multiple anthropogenic changes, including a larger walleye population resulting from better fisheries management, planned nutrient reductions to improve water quality and transparency, warmer water temperatures, and the proliferation of a non-native fish with novel traits (white perch, Morone americana). We argue that these changes may have reduced competitive interactions by reducing the spatial overlap between older and younger walleye and by introducing novel prey. Our findings illustrate the potential for anthropogenic change to diminish density dependent intraspecific interactions within top predator populations, which has important ramifications for predicting predator dynamics and managing natural resources.


Assuntos
Bass , Percas , Animais , Retroalimentação , Lagos , Temperatura , Comportamento Predatório
3.
Endocr Connect ; 10(9): 1180-1188, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34424854

RESUMO

PURPOSE: Five percent of patients with differentiated thyroid cancer are diagnosed with radioiodine refractory relapse in the course of the disease. For isolated or oligometastatic cervical recurrence, resection or another local treatment is recommended. In this study, the impact of surgical treatment of cervical radioiodine refractory 18F-FDG-PET positive relapse of papillary thyroid cancer (PTC) was evaluated. METHODS: Patients receiving radioiodine therapy between 2005 and 2015 at the University Hospital of Cologne, Germany, for PTC were screened. The subgroup of patients undergoing surgery during the course of disease after recommendation by a multidisciplinary endocrine team for cervical radioiodine refractory 18F-FDG-PET positive recurrence was identified. Demographics, clinic-pathologic characteristics, oncologic treatment, and outcome were analyzed. RESULTS: Thirty (3%) of 969 patients with PTC treated with radioiodine therapy at our institution underwent surgery for radioiodine refractory 18F-FDG-PET positive cervical recurrence during the course of the disease. In eight (26.6%) patients, more than one operation was performed. Sixteen (53%) patients received external beam radiation therapy (EBRT) after surgery. Follow-up was on average, 79.2 ± 61.6 months after the last surgical treatment. Biochemical and radiological cure was seen in 12 (40%) patients. Remission was significantly more frequent in younger patients (P = 0.0001) with lymph node rather than soft tissue tumor recurrence (P = 0.004). CONCLUSIONS: Surgical treatment of radioiodine refractory 18F-FDG-PET positive cervical recurrence led to biochemical and radiological cure in about 40% of patients in this study. Further data are needed concerning risk stratification of potential subgroups benefitting of surgical approach and the possible role of EBRT after repetitive surgery.

4.
J Dairy Sci ; 103(8): 7462-7471, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32534924

RESUMO

Two experiments were conducted to evaluate the effects of the timing of artificial insemination (AI) and incorporation of the Slo3 K+ channel blocker 4-(4-chlorophenyl)butyl-diethyl-heptylammonium to semen extender (CSE) on pregnancy per AI (P/AI) and pregnancy loss in dairy heifers. In experiment 1, Holstein heifers were subjected to the 5-d CIDR-Synch protocol: d -8 GnRH and controlled internal drug-release device (CIDR); d -3 PGF2α and CIDR removal; d -2 PGF2α; d 0 GnRH) and assigned randomly to receive timed AI with control semen on d 0 (72-CON; n = 104), control semen on d -1 (48-CON; n = 100), or CSE-treated semen on d -1 (48-CSE; n = 98). Heifers were fitted with collar-mounted automated estrus detection devices to monitor physical activity and rumination. In experiment 2, Holstein heifers were subjected to the 5-d CIDR-Synch protocol and received a mount detection patch at the first PGF2α injection. Heifers detected in estrus before d 0 were inseminated on the same day, whereas those not detected in estrus received the second GnRH injection and timed AI on d 0. Heifers were assigned randomly to receive AI with control (AI-CON; n = 148) or CSE-treated semen (AI-CSE; n = 110). Four bulls with proven fertility were used in both experiments, and ejaculates from each sire were divided and processed as CON or CSE. Pregnancy was diagnosed by transrectal ultrasonography at 29 and 54 d after AI. Data were analyzed by logistic regression, and statistical models included the fixed effects of treatment and enrollment week. In experiment 1, orthogonal contrasts were built to assess the effects of day of AI (72-CON vs. 48-CON + 48-CSE) and treatment of semen with CSE (48-CON vs. 48-CSE). Pregnancy per AI on d 29 (72-CON = 60.8, 48-CON = 35.2, 48-CSE = 39.8%) and d 54 (72-CON = 58.2, 48-CON = 31.6, 48-CSE = 36.2%) was greater for heifers inseminated on d 0 compared with d -1. However, no effect of semen extender on P/AI was observed in heifers inseminated on d -1. In experiment 2, P/AI tended to be greater for AI-CSE than for AI-CON on d 29 (58.6 vs. 47.3%) and d 54 after AI (55.6 vs. 43.7%). Advancing AI by 24 h decreased the likelihood of pregnancy, and use of CSE was unable to overcome the expected asynchrony between insemination and ovulation. Nevertheless, incorporation of CSE in semen processing tended to improve P/AI when heifers received AI upon detected estrus or timed AI concurrently with the final GnRH of the 5-d CIDR-Synch protocol.


Assuntos
Fertilidade/efeitos dos fármacos , Inseminação Artificial/veterinária , Bloqueadores dos Canais de Potássio/farmacologia , Sêmen/efeitos dos fármacos , Animais , Bovinos , Sistemas de Liberação de Medicamentos , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Canais de Potássio Ativados por Cálcio de Condutância Alta/antagonistas & inibidores , Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Masculino , Gravidez , Progesterona/administração & dosagem , Fatores de Tempo
6.
Sci Total Environ ; 521-522: 211-8, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25841074

RESUMO

The vision of a sustainable and safe use of chemicals to protect human health, preserve the environment and maintain the ecosystem requires innovative and more holistic approaches to risk assessment (RA) in order to better inform decision making. Integrated risk assessment (IRA) has been proposed as a solution to current scientific, societal and policy needs. It is defined as the mutual exploitation of environmental risk assessment (ERA) for human health risk assessment (HHRA) and vice versa in order to coherently and more efficiently characterize an overall risk to humans and the environment for better informing the risk analysis process. Extrapolating between species which are relevant for HHRA and ERA requires a detailed understanding of pathways of toxicity/modes of action (MoA) for the various toxicological endpoints. Significant scientific advances, changes in chemical legislation, and increasing environmental consciousness have created a favourable scientific and regulatory environment to develop and promote the concept and vision of IRA. An initial proof of concept is needed to foster the incorporation of IRA approaches into different chemical sectorial regulations and demonstrate their reliability for regulatory purposes. More familiarity and confidence with IRA will ultimately contribute to an overall reduction in in vivo toxicity testing requirements. However, significant progress will only be made if long-term support for MoA-related research is secured. In the short term, further exchange and harmonization of RA terminology, models and methodologies across chemical categories and regulatory agencies will support these efforts. Since societal values, public perceptions and cultural factors are of increasing importance for the acceptance of risk analysis and successful implementation of risk mitigation measures, the integration of socio-economic analysis and socio-behavioural considerations into the risk analysis process may help to produce a more effective risk evaluation and consideration of the risks and benefits associated with the use of chemicals.


Assuntos
Monitoramento Ambiental/métodos , Política Ambiental , Poluentes Ambientais/toxicidade , Monitoramento Ambiental/legislação & jurisprudência , União Europeia , Substâncias Perigosas/toxicidade , Medição de Risco/métodos
7.
Internist (Berl) ; 55(10): 1149-56, 2014 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-25204533

RESUMO

The use of thyroid-stimulating hormone (TSH) testing in routine laboratory screening and testing of TSH before administration of contrast medium, resulted in an increased number of incidentally detected elevated TSH levels. In the case of slightly increased values in asymptomatic patients, repeated measurement of TSH is recommended for confirmation. Confirmed elevated TSH levels should lead to additional measurements of the peripheral thyroid hormones, determination of thyroid autoantibodies and performance of thyroid gland ultrasound examination. The most common reasons for acquired subclinical and overt hypothyroidism are autoimmune diseases of the thyroid gland and in many cases substitution therapy with levothyroxine is then necessary. In subclinical hypothyroidism it remains unclear at which TSH levels the initiation of substitution therapy makes sense. In the case of simultaneously elevated peripheral thyroid hormones rare diseases, such as secondary hyperthyroidism and thyroid hormone resistance should be considered.


Assuntos
Erros de Diagnóstico/prevenção & controle , Hipotireoidismo/sangue , Hipotireoidismo/diagnóstico , Achados Incidentais , Programas de Rastreamento/métodos , Tireotropina/sangue , Biomarcadores/sangue , Diagnóstico Diferencial , Humanos
8.
Am J Perinatol ; 31(9): 773-80, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24623338

RESUMO

The structural and functional development of the kidney is responsible for a significant impact on postnatal adaptation to extrauterine life. Prenatal or neonatal impairment of nephrogenesis may carry long term, lifelong consequences in terms of reduced nephron endowment, chronic kidney disease, and cardiovascular risks at adulthood. Intrauterine growth restriction, preterm birth, congenital renal, and urinary tract anomalies are for long widely incriminated. Neonatal administration of nephrotoxic drugs has been associated with short-term acute kidney injury and longer chronic kidney disease. This review attempts at offering a comprehensive understanding of the renal development, the neonatal renal transition to extrauterine life and subsequent maturation phase during early infancy. It also focuses on developmental and maturational changes that impact lifelong renal function and adult health.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Adaptação Fisiológica , Rim/embriologia , Rim/fisiologia , Animais , Desenvolvimento Fetal , Taxa de Filtração Glomerular , Humanos , Recém-Nascido , Rim/irrigação sanguínea , Rim/crescimento & desenvolvimento , Nascimento Prematuro/fisiopatologia , Circulação Renal , Insuficiência Renal Crônica/etiologia
9.
Horm Metab Res ; 46(4): 283-6, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24198220

RESUMO

The concentration of serum testosterone is mainly regulated by the testicular function, which is under control of the central hypothalamic-pituitary-gonadal axis. A certain amount of testosterone is converted into ß-estradiol by adipose tissue. Obesity in men is often associated with decreased androgen levels. The aim of the present study was to examine the effect of caloric restriction on serum testosterone levels in obese men. Dietary intervention study was performed with a very low calorie diet (800 kcal/d) for 12 weeks. Thirteen obese human male subjects (median body mass index: 42.7 kg/m2) were included. Body composition was assessed by impedance analysis. Insulin sensitivity was estimated by leptin-to-adiponectin ratio (LAR). Testosterone (T), ß-estradiol, albumin, sex hormone-binding globulin (SHBG), LH, and FSH serum concentrations were measured by enzyme immunoassays. Statistical analysis was performed on baseline and values after 3 months. Caloric restriction significantly increased total testosterone (6.97 nmol/l to 13.21 nmol/l; p=0.001) and SHBG (22.11 nmol/l to 42.12 nmol/l; p=0.001) concentrations in serum. This is caused by a significant improvement of the testicular function (LH/T: 0.36-0.20; p=0.005) and a significant reduction of the T/ß-estradiol conversion rate (73.59-104.29; p=0.003). There was a significant negative correlation of improvement of testicular function and LAR (rs=-0.683 (p=0.042)). In obese men caloric restriction significantly increases the serum testosterone concentration. This is achieved by 2 distinct mechanisms, that is, improvement of testicular function and reduced conversion of testosterone to ß-estradiol by aromatase activity of the adipose tissue.


Assuntos
Restrição Calórica , Obesidade/sangue , Testosterona/sangue , Adiponectina/sangue , Adulto , Estradiol/sangue , Humanos , Resistência à Insulina , Leptina/sangue , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Testículo/fisiopatologia
10.
Int J Nephrol ; 2013: 346067, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24073334

RESUMO

Cardiovascular diseases are one of the leading causes of mortality. Hypertension (HT) is one of the principal risk factors associated with death. Chronic kidney disease (CKD), which is probably underestimated, increases the risk and the severity of adverse cardiovascular events. It is now recognized that low birth weight is a risk factor for these diseases, and this relationship is amplified by a rapid catch-up growth or overfeeding during infancy or childhood. The pathophysiological and molecular mechanisms involved in the "early programming" of CKD are multiple and partially understood. It has been proposed that the developmental programming of arterial hypertension and chronic kidney disease is related to a reduced nephron endowment. However, this mechanism is still discussed. This review discusses the complex relationship between birth weight and nephron endowment and how early growth and nutrition influence long term HT and CKD. We hypothesize that fetal environment reduces moderately the nephron number which appears insufficient by itself to induce long term diseases. Reduced nephron number constitutes a "factor of vulnerability" when additional factors, in particular a rapid postnatal growth or overfeeding, promote the early onset of diseases through a complex combination of various pathophysiological pathways.

11.
Sci Total Environ ; 456-457: 307-16, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23624004

RESUMO

For more than a decade, the integration of human and environmental risk assessment (RA) has become an attractive vision. At the same time, existing European regulations of chemical substances such as REACH (EC Regulation No. 1907/2006), the Plant Protection Products Regulation (EC regulation 1107/2009) and Biocide Regulation (EC Regulation 528/2012) continue to ask for sector-specific RAs, each of which have their individual information requirements regarding exposure and hazard data, and also use different methodologies for the ultimate risk quantification. In response to this difference between the vision for integration and the current scientific and regulatory practice, the present paper outlines five medium-term opportunities for integrating human and environmental RA, followed by detailed discussions of the associated major components and their state of the art. Current hazard assessment approaches are analyzed in terms of data availability and quality, and covering non-test tools, the integrated testing strategy (ITS) approach, the adverse outcome pathway (AOP) concept, methods for assessing uncertainty, and the issue of explicitly treating mixture toxicity. With respect to exposure, opportunities for integrating exposure assessment are discussed, taking into account the uncertainty, standardization and validation of exposure modeling as well as the availability of exposure data. A further focus is on ways to complement RA by a socio-economic assessment (SEA) in order to better inform about risk management options. In this way, the present analysis, developed as part of the EU FP7 project HEROIC, may contribute to paving the way for integrating, where useful and possible, human and environmental RA in a manner suitable for its coupling with SEA.


Assuntos
Exposição Ambiental , Substâncias Perigosas/toxicidade , Medição de Risco/métodos , Testes de Toxicidade , Alternativas aos Testes com Animais , Animais , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , União Europeia , Regulamentação Governamental , Humanos , Medição de Risco/legislação & jurisprudência , Medição de Risco/tendências , Fatores Socioeconômicos , Testes de Toxicidade/economia , Testes de Toxicidade/métodos , Testes de Toxicidade/normas
12.
J Dairy Sci ; 96(1): 668-78, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23063157

RESUMO

Genomic evaluations for 161,341 Holsteins were computed by using 311,725 of 777,962 markers on the Illumina BovineHD Genotyping BeadChip (HD). Initial edits with 1,741 HD genotypes from 5 breeds revealed that 636,967 markers were usable but that half were redundant. Holstein genotypes were from 1,510 animals with HD markers, 82,358 animals with 45,187 (50K) markers, 1,797 animals with 8,031 (8K) markers, 20,177 animals with 6,836 (6K) markers, 52,270 animals with 2,683 (3K) markers, and 3,229 nongenotyped dams (0K) with >90% of haplotypes imputable because they had 4 or more genotyped progeny. The Holstein HD genotypes were from 1,142 US, Canadian, British, and Italian sires, 196 other sires, 138 cows in a US Department of Agriculture research herd (Beltsville, MD), and 34 other females. Percentages of correctly imputed genotypes were tested by applying the programs findhap and FImpute to a simulated chromosome for an earlier population that had only 1,112 animals with HD genotypes and none with 8K genotypes. For each chip, 1% of the genotypes were missing and 0.02% were incorrect initially. After imputation of missing markers with findhap, percentages of genotypes correct were 99.9% from HD, 99.0% from 50K, 94.6% from 6K, 90.5% from 3K, and 93.5% from 0K. With FImpute, 99.96% were correct from HD, 99.3% from 50K, 94.7% from 6K, 91.1% from 3K, and 95.1% from 0K genotypes. Accuracy for the 3K and 6K genotypes further improved by approximately 2 percentage points if imputed first to 50K and then to HD instead of imputing all genotypes directly to HD. Evaluations were tested by using imputed actual genotypes and August 2008 phenotypes to predict deregressed evaluations of US bulls proven after August 2008. For 28 traits tested, the estimated genomic reliability averaged 61.1% when using 311,725 markers vs. 60.7% when using 45,187 markers vs. 29.6% from the traditional parent average. Squared correlations with future data were slightly greater for 16 traits and slightly less for 12 with HD than with 50K evaluations. The observed 0.4 percentage point average increase in reliability was less favorable than the 0.9 expected from simulation but was similar to actual gains from other HD studies. The largest HD and 50K marker effects were often located at very similar positions. The single-breed evaluation tested here and previous single-breed or multibreed evaluations have not produced large gains. Increasing the number of HD genotypes used for imputation above 1,074 did not improve the reliability of Holstein genomic evaluations.


Assuntos
Bovinos/genética , Genômica/métodos , Animais , Cruzamento/métodos , Feminino , Marcadores Genéticos/genética , Genótipo , Masculino , Fenótipo , Característica Quantitativa Herdável
13.
Nuklearmedizin ; 51(6): 228-33, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22940904

RESUMO

AIM: The positive predictive value (PPV) of a slightly elevated basal calcitonin (CT) for the diagnosis of medullary thyroid cancer (MTC) is still under debate. PATIENTS, METHODS: A total of 11270 patients with thyroid nodules underwent calcitonin screening. Patients with known elevation of CT, renal insufficiency, bacterial infection, alcohol abuse, proton-pump inhibitor therapy or autoimmune thyroid disease were excluded from further analysis. Serum CT was determined by the solid-phase, enzyme-labeled, two-site chemiluminescent immunoassay Immulite 2000. If possible, a pentagastrin test was done to differentiate cases of hypercalcitoninaemia. RESULTS: Hypercalcitoninsemia was found in 32 patients. 20 patients underwent surgery. In 10 patients a MTC was found. The PPV of hypercalcitoninaemia for MTC was 31%. The PPV increased to 50% for those patients who underwent surgery (10/20). A subgroup of 26 patients presented with basal CT between 13 and 50 pg/ml, 14 of them underwent surgery, in 4 cases evidence of MTC was revealed. This resulted in a PPV of 15% (4/26), although the value increased to 28% when only surgically treated patients were considered (4/14). CONCLUSION: Taking all clinical data into account, calcitonin screening has an acceptable PPV for medullary thyroid cancer in patients with thyroid nodules. Therefore, we recommend calcitonin screening in centers for thyroid disorders.


Assuntos
Biomarcadores Tumorais/sangue , Calcitonina/sangue , Programas de Rastreamento/estatística & dados numéricos , Nódulo da Glândula Tireoide/sangue , Nódulo da Glândula Tireoide/epidemiologia , Adulto , Idoso , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Prevalência , Reprodutibilidade dos Testes , Medição de Risco , Sensibilidade e Especificidade , Nódulo da Glândula Tireoide/diagnóstico
14.
Fortschr Neurol Psychiatr ; 80(4): 221-6, 2012 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-22473685

RESUMO

Acute intermittent porphyria is a hereditary disorder resulting from a partial deficiency of the third enzyme in the haeme biosynthetic pathway. Symptoms are due to metabolic effects on the peripheral autonomic and sensomotoric, as well as the central nervous system. We report on the case of a life-threatening acute crisis with tetraplegia and respiratory insufficiency.


Assuntos
Doenças do Sistema Nervoso Periférico/etiologia , Porfiria Aguda Intermitente/complicações , Quadriplegia/etiologia , Insuficiência Respiratória/etiologia , Eletrocardiografia , Feminino , Humanos , Transtornos Mentais/etiologia , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/etiologia
15.
Horm Metab Res ; 44(6): 465-70, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22438213

RESUMO

Inflammatory mechanisms are involved in the pathogenesis of type 2 diabetes with interleukin (IL)-6 being particularly important. While long term exercise has been shown to be associated with reduction in IL-6 serum levels in several reports, the discussion on the effect of dietary intervention on IL-6 serum levels is controversial. In the present study, we aimed to investigate the effect of weight loss due to a very low calorie diet (VLCD) on insulin sensitivity and IL-6 serum levels in nondiabetic obese human individuals. 10 patients with obesity were examined during 12 weeks of a VLCD (800 kcal/d). Body composition was measured by impedance analysis. Blood samples were taken before, during, and after the dietary intervention. Leptin, adiponectin, and IL-6 serum levels were measured by ELISA. The body weight decreased significantly from 123.9±6.2-103.5±5.6 kg with a significant reduction in body fat content (43.2±2.3-36.1±3.1%). Leptin levels exhibited a significant decrease from 56.8±5.6-27.9±5.6 ng/ml while adiponectin levels increased significantly from 7.5±0.9-10.6±1.1 µg/ml. Thereby the leptin-to-adiponectin ratio, a novel marker for insulin sensitivity, significantly improved. Mean IL-6 serum concentrations were within the normal range (3.2±0.8 pg/ml) before the study and were not significantly altered by the nutritional therapy. Despite improvement of insulin sensitivity, IL-6 serum levels did not change throughout the study period, suggesting that in nondiabetic obese human subjects IL-6 might have only a minor role in the impairment of insulin sensitivity.


Assuntos
Restrição Calórica , Resistência à Insulina , Interleucina-6/sangue , Obesidade/sangue , Obesidade/dietoterapia , Redução de Peso , Adipocinas/sangue , Adulto , Glicemia/metabolismo , Composição Corporal , Peso Corporal , Proteína C-Reativa/metabolismo , Diabetes Mellitus/sangue , Jejum/sangue , Feminino , Humanos , Inflamação/sangue , Inflamação/complicações , Inflamação/patologia , Metabolismo dos Lipídeos , Masculino , Obesidade/complicações , Obesidade/patologia
16.
Int J Androl ; 35(3): 303-16, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22372636

RESUMO

By diminishing the action of androgens during gestation, certain chemicals can induce irreversible demasculinization and malformations of sex organs in the male rat after gestational exposure. Studies with mixtures of such anti-androgens have shown that substantial combined effects occur even though each individual chemical is present at low, ineffective doses, but the effects of mixtures modelled based on human intakes have not previously been investigated. To address this issue for the first time, we selected 13 chemicals for a developmental mixture toxicity study in rats where data about in vivo endocrine disrupting effects and information about human exposures was available, including phthalates, pesticides, UV-filters, bisphenol A, parabens and the drug paracetamol. The mixture ratio was chosen to reflect high end human intakes. To make decisions about the dose levels for studies in the rat, we employed the point of departure index (PODI) approach, which sums up ratios between estimated exposure levels and no-observed-adverse-effect-level (NOAEL) values of individual substances. For high end human exposures to the 13 selected chemicals, we calculated a PODI of 0.016. As only a PODI exceeding 1 is expected to lead to effects in the rat, a total dose more than 62 times higher than human exposures should lead to responses. Considering the high uncertainty of this estimate, experience on lowest-observed-adverse-effect-level (LOAEL)/NOAEL ratios and statistical power of rat studies, we expected that combined doses 150 times higher than high end human intake estimates should give no, or only borderline effects, whereas doses 450 times higher should produce significant responses. Experiments indeed showed clear developmental toxicity of the 450-fold dose in terms of increased nipple retention (NR) and reduced ventral prostate weight. The 150-fold dose group exhibited significantly increased NR. These observations suggest that highly exposed population groups, especially women of reproductive age, may not be protected sufficiently against the combined effects of chemicals that affect the hormonal milieu required for normal male sexual differentiation.


Assuntos
Antagonistas de Androgênios/toxicidade , Disruptores Endócrinos/toxicidade , Anormalidades Induzidas por Medicamentos , Animais , Feminino , Genitália/anormalidades , Humanos , Masculino , Nível de Efeito Adverso não Observado , Gravidez , Ratos , Ratos Wistar , Diferenciação Sexual/efeitos dos fármacos
18.
Klin Monbl Augenheilkd ; 228(6): 509-14, 2011 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-21656433

RESUMO

BACKGROUND: During the UVA-cross-linking treatment in keratoconus patients, the UVA rays are partially absorbed in the stroma of the riboflavin-loaded cornea. This effect protects the corneal endothelium from UVA irradiation damage. The intensity of UVA light reaching the endothelium is inversely correlated with corneal thickness. The common composition of riboflavin eye drops may lead to a marked reduction in corneal thickness increasing the risk of endothelial damage. PATIENTS AND METHODS: In a retrospective analysis of 23 UVA-cross-linking procedures on 23 patients we collected data about the pre-, intra- and postoperative corneal thickness (measured with ultrasound). Among these patients and depending on the preoperative state, 8 eyes received Medio Cross (TM) eye drops (group 1), 8 eyes received Medio Cross (TM) eye drops combined with riboflavin 0.1 %/methylhydroxypropylcellulose 1,5 %/NaCl 1.1 % (group 2) and 7 eyes received riboflavin 0.2 %/methylhydroxypropylcellulose 0.5 %/NaCl 0.7 % eye drops (group 3) before and during UVA irradiation. Data are presented as means ± standard deviation. A comparison of the data was performed using (one-way) ANOVA. RESULTS: The mean corneal thickness at the end of the UVA cross-linking procedure was 67 ± 9 % (means ± standard deviation) of preoperative thickness in group 1, 118 ± 14 % in group 2 and 140 ± 23 % in group 3. The values in groups 2 and 3 were significantly different from those in the reference group 1. CONCLUSIONS: Our results show a strong variability of the postoperative corneal thickness using different standard compositions of riboflavin eye drops. Further studies are needed to find a composition of riboflavin eye drops ensuring a moderate increase in intraoperative corneal thickness to protect the corneal endothelium.


Assuntos
Córnea/efeitos dos fármacos , Córnea/fisiopatologia , Ceratocone/tratamento farmacológico , Ceratocone/fisiopatologia , Riboflavina/administração & dosagem , Adulto , Relação Dose-Resposta a Droga , Composição de Medicamentos , Feminino , Humanos , Cuidados Intraoperatórios/métodos , Masculino , Soluções Oftálmicas , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/administração & dosagem , Resultado do Tratamento , Raios Ultravioleta
20.
Int J Androl ; 33(2): 463-74, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20487045

RESUMO

There is widespread exposure to anti-androgens, a group of chemicals able to disrupt androgen action in foetal life, with irreversible de-masculinizing consequences. Substances of concern include certain phthalates, pesticides and chemicals used in cosmetics and personal care products. Although people come into contact with several anti-androgens, chemicals risk assessment normally does not take account of the effects of combined exposures. However, a disregard for combination effects may lead to underestimations of risks and for this reason, we have assessed the feasibility of conducting cumulative risk assessment, where the focus is on considering the effects of exposure to multiple chemicals, via multiple routes and pathways. Following recent recommendations by the US National Research Council, we have, for the first time, included phthalates and other anti-androgenic chemicals, a total of 15 substances. On the basis of exposure estimates for the individual chemicals and reference doses for anti-androgenicity, we have used the hazard index approach. We show that the cumulative risks from anti-androgen exposures exceed acceptable levels for people on the upper end of exposure levels. The value obtained for median exposures to the 15 substances can be judged tolerable. However, significant knowledge gaps exist that prevent us from arriving at definitive conclusions. Of greatest concern is an absence of appropriate in vivo toxicity data about large numbers of in vitro androgen receptor antagonists. Knowledge about the effect profiles of these chemicals will lead to higher risk estimates. Our analysis suggests that risk reductions can be achieved by limiting exposures to the plasticizer diethyl hexyl phthalate, the cosmetic ingredients butyl- and propyl paraben, the pesticides vinclozolin, prochloraz and procymidone and bisphenol A.


Assuntos
Antagonistas de Androgênios/toxicidade , Poluentes Ambientais/toxicidade , Ácidos Ftálicos/toxicidade , Medição de Risco/métodos , Animais , Combinação de Medicamentos , Exposição Ambiental , Disgenesia Gonadal/induzido quimicamente , Humanos , Masculino , Parabenos/toxicidade , Praguicidas/toxicidade , Receptores Androgênicos/efeitos dos fármacos , Diferenciação Sexual/efeitos dos fármacos , Estados Unidos
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