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1.
Mod Pathol ; 33(4): 713-721, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31695156

RESUMO

In 2016, the World Health Organization classification system of testicular tumors included the new entity prepubertal-type teratoma based on its morphological and molecular profile, and the realization that these tumors may occur in postpubertal men. For treatment and prognostic purposes, it is important to distinguish prepubertal-type teratoma from the usual postpubertal-type teratoma, because the former is benign unlike the latter. The distinction may be challenging. In this study, we investigated clinical, morphological, and molecular criteria for distinguishing prepubertal-type teratoma from postpubertal-type teratoma in a prospective series of pure testicular teratomas. All cases of pure teratoma in postpubertal men assessed at Barts Health NHS Trust or in consultation since the introduction of routine investigation of chromosome 12p status in 2010 were reviewed. Morphological features suggestive of prepubertal-type teratoma were observed in 14 out of 35 cases. All underwent molecular testing and none displayed 12p amplification. Mean tumor size was 16 mm (range 7-28 mm). None had associated germ cell neoplasia in situ or significant atrophy. Four incorporated a well-differentiated neuroendocrine tumor, 1-2 mm in size. Of the ten patients with follow-up information, none have recurred or metastasized. Twenty-one of the 35 cases were diagnosed as postpubertal-type teratoma, mean tumor size 40 mm (range 6-90 mm). One case underwent molecular testing: a tumor of pure skeletal muscle differentiation and possessed 12p amplification. Three cases presented with clinical metastases. Eight cases contained immature areas, ten cases had associated germ cell neoplasia in situ, and 17 cases had severe atrophy of the parenchyma. One case with neither germ cell neoplasia in situ nor atrophy showed necrosis. We conclude that both morphological and molecular features are of help in differentiating prepubertal-type teratoma from postpubertal-type teratoma. In nearly all postpubertal-type teratomas, molecular testing was unnecessary, and merely confirmed the morphological impression in the prepubertal-type teratomas. Our study confirmed the high incidence of well-differentiated neuroendocrine tumors in the prepubertal-type.


Assuntos
Biomarcadores Tumorais/genética , Puberdade , Teratoma/genética , Teratoma/patologia , Neoplasias Testiculares/genética , Neoplasias Testiculares/patologia , Adulto , Idoso , Biomarcadores Tumorais/análise , Biópsia , Diferenciação Celular , Diagnóstico Diferencial , Predisposição Genética para Doença , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular , Fenótipo , Valor Preditivo dos Testes , Estudos Prospectivos , Teratoma/química , Neoplasias Testiculares/química , Carga Tumoral , Adulto Jovem
2.
Clin Pharmacol Ther ; 104(3): 426-429, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30066384

RESUMO

The United States Pharmacopeia (USP) is an independent, nonprofit, science-based organization whose mission is to improve global health through public quality standards for dietary supplements, medicines, and food ingredients.1 Before developing standards for dietary supplement ingredients, the USP performs an "Admission Evaluation" (Figure 1), which includes an assessment to ascertain that an ingredient does not present a serious health risk.2 This article discusses the challenges encountered during the evaluation of botanicals and proposes possible solutions.


Assuntos
Qualidade de Produtos para o Consumidor/normas , Suplementos Nutricionais/normas , Segurança do Paciente/normas , Farmacopeias como Assunto/normas , Fitoterapia/normas , Preparações de Plantas/normas , Controle de Qualidade , Melhoria de Qualidade/normas , Animais , Suplementos Nutricionais/efeitos adversos , Humanos , Fitoterapia/efeitos adversos , Preparações de Plantas/efeitos adversos , Medição de Risco , Estados Unidos
3.
Clin Pharmacol Ther ; 104(3): 446-457, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29882956

RESUMO

Exposure to botanicals in dietary supplements is increasing across many geographies; with increased expectations from consumers, regulators, and industry stewards centered on quality and safety of these products. We present a tiered approach to assess the safety of botanicals, and an in silico decision tree to address toxicity data gaps. Tier 1 describes a Threshold of Toxicologic Concern (TTC) approach that can be used to assess the safety of conceptual levels of botanicals. Tier 2 is an approach to document a history of safe human use for botanical exposures higher than the TTC. An assessment of botanical-drug interaction (BDI) may also be necessary at this stage. Tier 3 involves botanical chemical constituent identification and safety assessment and the in silico approach as needed. Our novel approaches to identify potential hazards and establish safe human use levels for botanicals is cost and time efficient and minimizes reliance on animal testing.


Assuntos
Qualidade de Produtos para o Consumidor , Suplementos Nutricionais/efeitos adversos , Indústria Farmacêutica , Segurança do Paciente , Fitoterapia/efeitos adversos , Preparações de Plantas/efeitos adversos , Plantas Medicinais/efeitos adversos , Testes de Toxicidade/normas , Animais , Qualidade de Produtos para o Consumidor/normas , Suplementos Nutricionais/normas , Indústria Farmacêutica/normas , Humanos , Segurança do Paciente/normas , Fitoterapia/normas , Preparações de Plantas/normas , Controle de Qualidade , Medição de Risco
4.
Toxicol In Vitro ; 50: 137-146, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29499337

RESUMO

When performing safety assessment of chemicals, the evaluation of their systemic toxicity based only on non-animal approaches is a challenging objective. The Safety Evaluation Ultimately Replacing Animal Test programme (SEURAT-1) addressed this question from 2011 to 2015 and showed that further research and development of adequate tools in toxicokinetic and toxicodynamic are required for performing non-animal safety assessments. It also showed how to implement tools like thresholds of toxicological concern (TTCs) and read-across in this context. This paper shows a tiered scientific workflow and how each tier addresses the four steps of the risk assessment paradigm. Cosmetics Europe established its Long Range Science Strategy (LRSS) programme, running from 2016 to 2020, based on the outcomes of SEURAT-1 to implement this workflow. Dedicated specific projects address each step of this workflow, which is introduced here. It tackles the question of evaluating the internal dose when systemic exposure happens. The applicability of the workflow will be shown through a series of case studies, which will be published separately. Even if the LRSS puts the emphasis on safety assessment of cosmetic relevant chemicals, it remains applicable to any type of chemical.


Assuntos
Alternativas aos Testes com Animais/métodos , Testes de Toxicidade/métodos , Animais , Cosméticos , Europa (Continente) , Humanos , Pesquisa , Medição de Risco/métodos
5.
Drug Metab Dispos ; 31(7): 815-32, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12814957

RESUMO

Current regulatory guidances do not address specific study designs for in vitro and in vivo drug-drug interaction studies. There is a common desire by regulatory authorities and by industry sponsors to harmonize approaches, to allow for a better assessment of the significance of findings across different studies and drugs. There is also a growing consensus for the standardization of cytochrome P450 (P450) probe substrates, inhibitors and inducers and for the development of classification systems to improve the communication of risk to health care providers and to patients. While existing guidances cover mainly P450-mediated drug interactions, the importance of other mechanisms, such as transporters, has been recognized more recently, and should also be addressed. This article was prepared by the Pharmaceutical Research and Manufacturers of America (PhRMA) Drug Metabolism and Clinical Pharmacology Technical Working Groups and represents the current industry position. The intent is to define a minimal best practice for in vitro and in vivo pharmacokinetic drug-drug interaction studies targeted to development (not discovery support) and to define a data package that can be expected by regulatory agencies in compound registration dossiers.


Assuntos
Indústria Farmacêutica , Interações Medicamentosas , Projetos de Pesquisa , Sistema Enzimático do Citocromo P-450/classificação , Sistema Enzimático do Citocromo P-450/metabolismo
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