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1.
Clin Pract Cases Emerg Med ; 6(1): 21-24, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35226841

RESUMO

INTRODUCTION: As the medical community and world have combatted the coronavirus disease 2019 (COVID-19) pandemic, a significant advance was the development of a vaccine against the virus that has already claimed over 4.5 million lives worldwide. Vaccines manufactured by Pfizer-BioNTech and Moderna were the first two COVID-19 vaccines given emergency use authorization by the United States Food and Drug Administration. Preliminary data demonstrated not only the vaccines' efficacy rates of greater than 95% after a second dose, but also marked safety. Initial data showed only 21 cases of anaphylaxis of greater than 1.8 million doses administered. The majority of those patients had a history of anaphylaxis and presented within the first 15 minutes after administration of the vaccine. CASE REPORT: We describe a patient who had an anaphylactic reaction to her second dose of the Pfizer BioNTech severe acute respiratory syndrome coronavirus 2 (SARS CoV-2) vaccine with no prior history of allergic reactions or anaphylaxis. This reaction required multiple doses of epinephrine and a four-day hospitalization. We review both the available reports of anaphylaxis to the SAR CoV-2 vaccine and information on other prolonged cases of anaphylaxis. CONCLUSION: Our case report is unique in that the patient, despite no prior history of anaphylaxis, had a prolonged course requiring a four-day hospitalization. To our knowledge this is one of the first case reports of prolonged anaphylaxis after the second dose of Pfizer BioNTech COVID-19 vaccine in a patient with no history of prior anaphylaxis.

2.
Food Chem Toxicol ; 161: 112822, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35063473

RESUMO

Manganese (Mn) is an essential trace element, but overexposure is associated with toxicity and neurological dysfunction. Accumulation of Mn can be observed in dopamine-rich regions of the brain in vivo and Mn-induced oxidative stress has been discussed extensively. Nevertheless, Mn-induced DNA damage, adverse effects of DNA repair, and possible resulting consequences for the neurite network are not yet characterized. For this, LUHMES cells were used, as they differentiate into dopaminergic-like neurons and form extensive neurite networks. Experiments were conducted to analyze Mn bioavailability and cytotoxicity of MnCl2, indicating a dose-dependent uptake and substantial cytotoxic effects. DNA damage, analyzed by means of 8-oxo-7,8-dihydro-2'-guanine (8oxodG) and single DNA strand break formation, showed significant dose- and time-dependent increase of DNA damage upon 48 h Mn exposure. Furthermore, the DNA damage response was increased which was assessed by analytical quantification of poly(ADP-ribosyl)ation (PARylation). Gene expression of the respective DNA repair genes was not significantly affected. Degradation of the neuronal network is significantly altered by 48 h Mn exposure. Altogether, this study contributes to the characterization of Mn-induced neurotoxicity, by analyzing the adverse effects of Mn on genome integrity in dopaminergic-like neurons and respective outcomes.


Assuntos
Cloretos/toxicidade , Neurônios/efeitos dos fármacos , Disponibilidade Biológica , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cloretos/farmacocinética , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Reparo do DNA/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Compostos de Manganês/farmacocinética , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Oligoelementos , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo
3.
Braz. dent. sci ; 25(3): 1-10, 2022. tab, ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1391014

RESUMO

Objective: Compare the clinical effectiveness of custom thermoformed occlusal splints (OS) alongside behavioral and self-care therapy (BST) in the management of myalgia of the masticatory muscles. Material and methods:A controlled clinical trial was conducted with a total of 46 subjects with a diagnosis of myalgia according to the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD). All subjects were treated with BST at the beginning of the study and were then randomized into four groups: behavioral and self-care control group; Thermoformed Tough-elastic splint group; Thermoformed Soft-elastic splint group, and non-occlusive splint group. Follow-ups were carried out at 2, 6, and 10 weeks, where it was evaluated: pain in the masticatory muscles, mandibular range of motion, mandibular functional limitation, and occlusal discomfort. Data were analyzed with Doornik and Hansen, Shapiro­Wilk, and ANOVA at p=0.05. Results: All the variables showed significant improvement (p<0.05) from the first follow-up and were maintained later. BST control group, as well as groups with BST associated with OS, were able to reduce pain and increase the mandibular range of motion without significant differences between them (p>0.05), while the Thermoformed Tough-elastic splint was the most efficient in terms of the mandibular functional limitation. The occlusal discomfort decreased over time, but without statistically significant differences in terms of time and design of OS. Conclusion: The addition of thermoformed OS to behavioral and self-care therapy does not have a significant impact on myalgia of the masticatory muscles. (AU)


Objetivo: Comparar a eficácia clínica das Placas Oclusais (PO) termoplásticas personalizadas associadas à Terapia Cognitiva Comportamental (TCC) na condução da mialgia dos músculos mastigatórios. Material e Métodos: Foi realizado um ensaio clínico controlado randomizado com um total de 46 participantes com um diagnóstico de mialgia de acordo com os Critérios de Diagnóstico das Desordens Temporomandibulares (DC/TMD). Todos os participantes foram tratados com a TCC, no início do estudo, e foram, depois, randomizados em quatro grupos: grupo controle Terapia Congnitivo Comportamental; grupo de placa termoplástica dura-soft, grupo de placa termoplástica soft, e grupo de placa sem cobertura oclusal. Foram realizados controles com 2, 6, e 10 semanas, onde foi avaliado: dor nos músculos mastigatórios, amplitude de movimento mandibular, limitação funcional mandibular, e desconforto oclusal. Os dados foram analisados com Doornik e Hansen, Shapiro-Wilk, e ANOVA a p=0,05. Resultados: Todas as variáveis mostraram melhora significativa (p<0,05) desde o primeiro controle e se mantiveram posteriormente. O grupo de controlo da TCC, bem como os grupos com TCC associada a PO, foram capazes de reduzir a dor e aumentar a amplitude de movimento mandibular sem diferenças significativas entre eles (p>0,05), enquanto que, a placa termoplástica dura-soft, foi a mais eficiente em termos da limitação mandibular funcional. O desconforto oclusal diminuiu ao longo do tempo, mas, sem diferenças estatisticamente significativas em termos de tempo e design da PO. Conclusão: A inclusão da Terapia Cognitivo Comportamental à PO termoplástica não tem um impacto significativo na mialgia dos músculos mastigatórios.(AU)


Assuntos
Humanos , Autocuidado , Síndrome da Disfunção da Articulação Temporomandibular , Placa Dentária , Mialgia
4.
Environ Mol Mutagen ; 62(4): 252-264, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33620775

RESUMO

TP53 harbors somatic mutations in more than half of human tumors with some showing characteristic mutation spectra that have been linked to environmental exposures. In bladder cancer, a unique distribution of mutations amongst several codons of TP53 has been hypothesized to be caused by environmental carcinogens including 4-aminobiphenyl (4-ABP). 4-ABP undergoes metabolic activation to N-hydroxy-4-aminobiphenyl (N-OH-4-ABP) and forms pre-mutagenic adducts in DNA, of which N-(deoxyguanosin-8-yl)-4-ABP (dG-C8-4-ABP) is the major one. Human TP53 knock-in mouse embryo fibroblasts (HUFs) are a useful model to study the influence of environmental carcinogens on TP53-mutagenesis. By performing the HUF immortalization assay (HIMA) TP53-mutant HUFs are generated and mutations can be identified by sequencing. Here we studied the induction of mutations in human TP53 after treatment of primary HUFs with N-OH-4-ABP. In addition, mutagenicity in the bacterial lacZ reporter gene and the formation of dG-C8-4-ABP, measured by 32 P-postlabelling analysis, were determined in N-OH-4-ABP-treated primary HUFs. A total of 6% TP53-mutants were identified after treatment with 40 µM N-OH-4-ABP for 24 hr (n = 150) with G>C/C>G transversion being the main mutation type. The mutation spectrum found in the TP53 gene of immortalized N-OH-4-ABP-treated HUFs was unlike the one found in human bladder cancer. DNA adduct formation (~40 adducts/108 nucleotides) was detected after 24 hr treatment with 40 µM N-OH-4-ABP, but lacZ mutagenicity was not observed. Adduct levels decreased substantially (sixfold) after a 24 hr recovery period indicating that primary HUFs can efficiently repair the dG-C8-4-ABP adduct possibly before mutations are fixed. In conclusion, the observed difference in the N-OH-4-ABP-induced TP53 mutation spectrum to that observed in human bladder tumors do not support a role of 4-ABP in human bladder cancer development.


Assuntos
Compostos de Aminobifenil/toxicidade , Adutos de DNA , Dano ao DNA , Mutagênese , Mutagênicos/toxicidade , Mutação , Proteína Supressora de Tumor p53/genética , Animais , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
5.
Food Chem Toxicol ; 147: 111855, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33189884

RESUMO

2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) is a possible human carcinogen formed in cooked fish and meat. PhIP is bioactivated by cytochrome P450 enzymes to form 2-hydroxyamino-1-methyl-6-phenylimidazo[4,5-b]pyridine (N-OH-PhIP), a genotoxic metabolite that reacts with DNA leading to the mutation-prone DNA adduct N-(deoxyguanosin-8-yl)-PhIP (dG-C8-PhIP). Here, we studied N-OH-PhIP-induced whole genome mutagenesis in human TP53 knock-in (Hupki) mouse embryo fibroblasts (HUFs) immortalised and subjected to whole genome sequencing (WGS). In addition, mutagenicity of N-OH-PhIP in TP53 and the lacZ reporter gene were assessed. TP53 mutant frequency in HUF cultures treated with N-OH-PhIP (2.5 µM for 24 h, n = 90) was 10% while no TP53 mutations were found in untreated controls (DMSO for 24 h, n = 6). All N-OH-PhIP-induced TP53 mutations occurred at G:C base pairs with G > T/C > A transversions accounting for 58% of them. TP53 mutations characteristic of those induced by N-OH-PhIP have been found in human tumours including breast and colorectal, which are cancer types that have been associated with PhIP exposure. LacZ mutant frequency increased 25-fold at 5 µM N-OH-PHIP and up to ~350 dG-C8-PhIP adducts/108 nucleosides were detected by ultra-performance liquid chromatography-electrospray ionisation multistage scan mass spectrometry (UPLC-ESI-MS3) at this concentration. In addition, a WGS mutational signature defined by G > T/C > A transversions was present in N-OH-PhIP-treated immortalised clones, which showed similarity to COSMIC SBS4, 18 and 29 signatures found in human tumours.


Assuntos
Fibroblastos/efeitos dos fármacos , Imidazóis/toxicidade , Piridinas/toxicidade , Proteína Supressora de Tumor p53/metabolismo , Animais , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Técnicas de Introdução de Genes , Humanos , Camundongos , Testes de Mutagenicidade , Proteína Supressora de Tumor p53/genética
6.
Arch Toxicol ; 94(12): 4173-4196, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32886187

RESUMO

Acrylamide is a suspected human carcinogen formed during high-temperature cooking of starch-rich foods. It is metabolised by cytochrome P450 2E1 to its reactive metabolite glycidamide, which forms pre-mutagenic DNA adducts. Using the human TP53 knock-in (Hupki) mouse embryo fibroblasts (HUFs) immortalisation assay (HIMA), acrylamide- and glycidamide-induced mutagenesis was studied in the tumour suppressor gene TP53. Selected immortalised HUF clones were also subjected to next-generation sequencing to determine mutations across the whole genome. The TP53-mutant frequency after glycidamide exposure (1.1 mM for 24 h, n = 198) was 9% compared with 0% in cultures treated with acrylamide [1.5 (n = 24) or 3 mM (n = 6) for 48 h] and untreated vehicle (water) controls (n = 36). Most glycidamide-induced mutations occurred at adenines with A > T/T > A and A > G/T > C mutations being the most common types. Mutations induced by glycidamide occurred at specific TP53 codons that have also been found to be mutated in human tumours (i.e., breast, ovary, colorectal, and lung) previously associated with acrylamide exposure. The spectrum of TP53 mutations was further reflected by the mutations detected by whole-genome sequencing (WGS) and a distinct WGS mutational signature was found in HUF clones treated with glycidamide that was again characterised by A > G/T > C and A > T/T > A mutations. The WGS mutational signature showed similarities with COSMIC mutational signatures SBS3 and 25 previously found in human tumours (e.g., breast and ovary), while the adenine component was similar to COSMIC SBS4 found mostly in smokers' lung cancer. In contrast, in acrylamide-treated HUF clones, only culture-related background WGS mutational signatures were observed. In summary, the results of the present study suggest that glycidamide may be involved in the development of breast, ovarian, and lung cancer.


Assuntos
Acrilamida/toxicidade , Compostos de Epóxi/toxicidade , Fibroblastos/efeitos dos fármacos , Mutagênese , Mutagênicos/toxicidade , Proteína Supressora de Tumor p53/genética , Animais , Linhagem Celular , Análise Mutacional de DNA , Fibroblastos/metabolismo , Fibroblastos/patologia , Regulação da Expressão Gênica , Técnicas de Introdução de Genes , Humanos , Camundongos , Proteína Supressora de Tumor p53/metabolismo , Sequenciamento Completo do Genoma
7.
Mutagenesis ; 35(6): 453-463, 2020 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-33399867

RESUMO

Chemicals in commerce or under development must be assessed for genotoxicity; assessment is generally conducted using validated assays (e.g. Tk mouse lymphoma assay) as part of a regulatory process. Currently, the MutaMouse FE1 cell mutagenicity assay is undergoing validation for eventual use as a standard in vitro mammalian mutagenicity assay. FE1 cells have been shown to be metabolically competent with respect to some cytochrome P450 (CYP) isozymes; for instance, they can convert the human carcinogen benzo[a]pyrene into its proximate mutagenic metabolite. However, some contradictory results have been noted for other genotoxic carcinogens that require two-step metabolic activation (e.g. 2-acetylaminofluorene and 2-amino-3-methylimidazo[4,5-f]quinoxaline). Here, we examined three known or suspected human carcinogens, namely acrylamide, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and 4-aminobiphenyl (4-ABP), together with their proximate metabolites (i.e. glycidamide, N-OH-PhIP and N-OH-4-ABP), to aid in the validation of the FE1 cell mutagenicity assay. Assessments of the parent compounds were conducted both in the presence and absence of an exogenous metabolic activation mixture S9; assessments of the metabolites were in the absence of S9. The most potent compound was N-OH-PhIP -S9, which elicited a mutant frequency (MF) level 5.3-fold over background at 5 µM. There was a 4.3-fold increase for PhIP +S9 at 5 µM, a 1.7-fold increase for glycidamide -S9 at 3.5 mM and a 1.5-fold increase for acrylamide +S9 at 4 mM. Acrylamide -S9 elicited a marginal 1.4-fold MF increase at 8 mM. Treatment with PhIP -S9, 4-ABP ±S9 and N-OH-4-ABP -S9 failed to elicit significant increases in lacZ MF with any of the treatment conditions tested. Gene expression of key CYP isozymes was quantified by RT-qPCR. Cyp1a1, 1a2 and 1b1 are required to metabolise PhIP and 4-ABP. Results showed that treatment with both compounds induced expression of Cyp1a1 and Cyp1b1 but not Cyp1a2. Cyp2e1, which catalyses the bioactivation of acrylamide to glycidamide, was not induced after acrylamide treatment. Overall, our results confirm that the FE1 cell mutagenicity assay has the potential for use alongside other, more traditional in vitro mutagenicity assays.


Assuntos
Carcinógenos Ambientais/farmacologia , Células Epiteliais/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Mutagênese/efeitos dos fármacos , Acrilamida/metabolismo , Acrilamida/farmacologia , Acrilamida/toxicidade , Animais , Carcinógenos Ambientais/metabolismo , Carcinógenos Ambientais/toxicidade , Linhagem Celular , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A2/genética , Citocromo P-450 CYP1B1/genética , Citocromo P-450 CYP2E1/genética , Células Epiteliais/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Imidazóis/metabolismo , Imidazóis/farmacologia , Imidazóis/toxicidade , Pulmão/patologia , Metaboloma/efeitos dos fármacos , Camundongos , Mutagênese/genética , Testes de Mutagenicidade , Quinoxalinas/metabolismo , Quinoxalinas/farmacologia , Quinoxalinas/toxicidade
8.
Methods Protoc ; 2(4)2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31766274

RESUMO

DNA in dividing cells is prone to mutagenesis, with mutations making key contributions to human disease including cancer. The tumour suppressor gene TP53 is the most frequently mutated gene in human tumours. Here, we present a robust protocol for studying TP53 mutagenesis utilising human TP53 knock-in (Hupki) mouse embryonic fibroblasts (HUFs). In the HUF immortalisation assay (HIMA), primary HUFs are treated with known or suspected carcinogens at 3% oxygen and then transferred to 20% atmospheric oxygen to induce senescence. Cells containing mutations (e.g., in TP53) that allow bypassing of senescence eventually emerge as immortalised clonal cell lines after 2-3 months of serial passaging. As not all immortalised HUF cells contain TP53 mutations, we developed a Nutlin-3a counter-screen to select for TP53-mutated clones prior to sequencing. TP53 mutation spectra generated can be compared with those of human tumours recorded in the International Agency for Research on Cancer TP53 mutation database. Environmental mutagens that have demonstrated and validated the utility of the HIMA include ultraviolet radiation, aristolochic acid, and benzo[a]pyrene. The TP53 mutation patterns induced by these mutagens in the HIMA corresponded to those found in human tumours from patients exposed to these mutagens. The approach presented helps to deepen our understanding of human cancer aetiology.

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