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1.
Talanta ; 273: 125910, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38492284

RESUMO

Paw San rice, also known as "Myanmar pearl rice", is considered the highest quality rice in Myanmar. There are considerable differences in terms of the premium commercial value of Paw San rice, which is an incentive for fraud, e.g. adulteration with cheaper rice varieties or mislabelling its geographical origin. Shwe Bo District is one of the most popular rice growing areas in the Sagaing region of Myanmar which produces the most valued and highly priced Paw San rice (Shwe Bo Paw San). The verification of the geographical origin of Paw San rice is not readily undertaken in the rice supply chain because the existing analytical approaches are time-consuming and expensive. Therefore, there is a need for rapid, robust and cost-effective analytical techniques for monitoring the authenticity and geographical origin of Paw San rice. In this 4-year study, two rapid screening techniques, Fourier-transform near-infrared (FT-NIR) spectroscopy and headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS), coupled with chemometric modelling, were applied and compared for the regional differentiation of Paw San rice. In addition, low-level fusion of the FT-NIR and HS-GC-IMS data was performed and its effect on the discriminative power of the chemometric models was assessed. Extensive model validation, including the validation using independent samples from a different production year, was performed. Furthermore, the effect of the sample preparation technique (grinding versus no sample preparation) on the performance of the discriminative model, obtained with FT-NIR spectral data, was assessed. The study discusses the suitability of FT-NIR spectroscopy, HS-GC-IMS and the combination of both approaches for rapid determination of the geographical origin of Paw San rice. The results demonstrated the excellent potential of the FT-NIR spectroscopy as well as HS-GC-IMS for the differentiation of Paw San rice cultivated in two distinct geographical regions. The OPLS-DA model, built using FT-NIR data of rice from 3 production years, achieved 96.67% total correct classification rate of an independent dataset from the 4th production year. The DD-SIMCA model, built using FT-NIR data of ground rice, also demonstrated the highest performance: 94% sensitivity and 97% specificity. This study has demonstrated that FT-NIR spectroscopy can be used as an accessible, rapid and cost-effective screening tool to discriminate between Paw San rice cultivated in the Shwe Bo and Ayeyarwady regions of Myanmar.


Assuntos
Oryza , Espectroscopia de Luz Próxima ao Infravermelho , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Quimiometria , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectrometria de Mobilidade Iônica/métodos , Mianmar
2.
Artigo em Inglês | MEDLINE | ID: mdl-34077339

RESUMO

Probabilistic exposure and risk assessment of chemical hazards in the diet have increasingly gained ground in recent years as a pragmatic approach for the approximation of reality. This work presents the outcomes of a project which aimed at applying probabilistic techniques for basic modelling of chronic dietary exposure to food contaminants following EFSA guidance. These techniques, based on Monte Carlo Risk Assessment (MCRA) software and on the programming language R, were employed for the risk assessment of cadmium for Austrian adults, enabling the validation and the critical comparison of the two approaches. Harmonisation and optimisation of procedures, refinement of exposure assessment skills and confidence in the results were the main benefits. Data amount and validity were identified as critical parameters, influencing the precision of the results. Cadmium was selected as a case study due to its toxicological properties, its ubiquitous presence in food and the availability of Austrian occurrence data. Similar exposure and risk estimates were generated through MCRA and R in alternative optimistic and pessimistic exposure scenarios, suggesting low levels of concern, except for vegetarians, whose upper tail exposures are close to the established Tolerable Weekly Intake. However, as occurrence data gaps have been identified as the major element of uncertainty, the estimated exposure and risk levels are characterised as underestimated. Grains and grain-based products, potatoes and leafy vegetables are the main contributors to the intake. The results will contribute to risk management and to a future refinement of the assessment.


Assuntos
Cádmio/efeitos adversos , Exposição Dietética/estatística & dados numéricos , Contaminação de Alimentos/análise , Medição de Risco/métodos , Gestão de Riscos/estatística & dados numéricos , Adolescente , Adulto , Idoso , Áustria , Dieta/estatística & dados numéricos , Exposição Dietética/efeitos adversos , Grão Comestível/química , Humanos , Pessoa de Meia-Idade , Modelos Estatísticos , Método de Monte Carlo , Vigilância da População , Software , Solanum tuberosum/química , Verduras/química
3.
Inhal Toxicol ; 33(4): 128-142, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33957849

RESUMO

OBJECTIVE: The objective of this study was the assessment of risks from inhalation exposure of Austrian smokers to cadmium through established toxicological approaches with emphasis on the exposure assessment component, which is challenging regarding the actual amount of metal that is inhaled and the simulation of the smoking pattern. MATERIALS AND METHODS: Exposure assessment comprised an estimation of the proportion of cadmium inhaled through smoking and actual occurrence data in tobacco products and survey smoking habits, which were integrated in alternative scenarios through a deterministic and a probabilistic Monte Carlo simulation method. Risks were characterized through the comparison of the exposure with health-based guidance values, as well as through the assessment of the excess lifetime cancer risk (ELCR), the non-cancer hazard quotient (NCHQ), and the margin of exposure (MOE). The strengths, the uncertainties, and the limitations of the different methodologies were discussed. RESULTS AND DISCUSSION: Upper exposures are close or exceed the Permitted Daily Exposure. Respiratory ELCRs are unacceptable compared to the benchmark range of 1.0E-06 to 1.0E-04. Renal and respiratory NCHQs exceed the target value of 1.0 by 3- to 17-fold. MOEs are not protective enough for cancer and non-cancer effects. The amount of cadmium that reaches the lung is a key source of uncertainty. CONCLUSION: Probabilistic estimates provide a refined capture of the actual inhalation exposure. Risk estimates and gender and age profiles are alarming, especially for young smokers. Application of toxicological approaches, combined with realistic assessment of the inhalation exposure levels, can support risk communication and management.


Assuntos
Cádmio/administração & dosagem , Simulação por Computador , Modelos Biológicos , Fumar Tabaco/efeitos adversos , Áustria , Humanos , Exposição por Inalação , Método de Monte Carlo , Medição de Risco , Fumantes , Fenômenos Toxicológicos
4.
Food Chem Toxicol ; 145: 111719, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32889018

RESUMO

Nitrates occur in food naturally, as contaminants or additives. The health implications attributed to ingested nitrates result primarily from their conversion into nitrites and subsequent methemoglobinemia, carcinogenicity induced by N-nitroso-compounds and cardiovascular, endocrine, metabolic, reproductive and developmental effects. The present study comprises a probabilistic tiered risk assessment of nitrates for Austrian adults through the diet with the application of the Monte Carlo simulation method in alternative optimistic and pessimistic scenarios. Risk estimates are of concern regarding the upper exposures, which exceed the Acceptable Daily Intake (ADI) in almost all scenarios and population groups. Exposure is elevated when all dietary sources are considered and the ADI is exceeded by already the mean intake for vegetarians. Leafy vegetables are major contributors to the intake. Contribution of cured meat is very low. Estimates of the conversion of nitrates into nitrites were used to assess the combined exposure to both species. When the average intake of nitrates and nitrites is considered, the mean exposure to nitrites is lower or close to the ADI for individuals with average conversion capacity. However, upper tail combined intake can lead to a multifold exceedance of the ADI of nitrites for individuals with both high and average conversion capacity.


Assuntos
Exposição Dietética/análise , Nitratos/metabolismo , Nitritos/metabolismo , Adulto , Idoso , Animais , Áustria , Feminino , Aditivos Alimentares/análise , Aditivos Alimentares/metabolismo , Humanos , Masculino , Produtos da Carne/análise , Pessoa de Meia-Idade , Nitratos/análise , Nitritos/análise , Nível de Efeito Adverso não Observado , Medição de Risco , Verduras/metabolismo , Adulto Jovem
5.
Food Chem Toxicol ; 143: 111480, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32533995

RESUMO

Nitrites are present in the food chain as naturally occurring species or contaminants. Additionally, sodium and potassium nitrites are authorised food additives. Nitrites exert acute toxicity through methemoglobinemia or cardiovascular effects, chronic toxicity associated with endocrine, reproductive and developmental effects and have been classified as probable gastric carcinogens. Ingestion of food and water are the main sources of human exposure. This study comprises a tiered risk assessment of nitrites for the Austrian adult population, along with the identification of the food categories most contributing to their intake. The dietary exposure, based on Austrian occurrence and consumption data, was modelled with the Monte Carlo simulation method. In an additional scenario, data gaps were addressed with the usage of occurrence data published by the European Food Safety Authority and from the available literature to account for the exposure from all sources. Risk estimates regarding only the exposure to nitrite additives and to contaminated water indicate low level of concern. However, when exposure from all sources is considered, the estimated exposure is elevated and exceeds the Acceptable Daily Intake for high consumers. Mean exposure attributed to the use of nitrites as additives accounts for only a very small proportion of the total intake.


Assuntos
Dieta , Exposição Dietética , Contaminação de Alimentos , Produtos da Carne/análise , Modelos Biológicos , Nitritos/administração & dosagem , Adulto , Animais , Áustria , Aditivos Alimentares/análise , Manipulação de Alimentos , Humanos , Nitritos/toxicidade , Nível de Efeito Adverso não Observado , Medição de Risco , Software
6.
Spec Care Dentist ; 40(1): 113-120, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31674703

RESUMO

BACKGROUND/AIM: Osteopetrosis is an inherited disease characterized by increased bone density. Its genetic variability results in various phenotype expressions, whereas clinically are classified in three types: malignant infantile, intermediate and adult. The various oral manifestations of the disease give a crucial role to the pediatric dentists in diagnosis. CASE PRESENTATION: A 7-year-old girl with persistent swelling on right cheek visited a pedodontic clinic. After extra- and intra-oral examination/findings, the patient was referred for further investigation concerning a possible general pathological background. An extraction, included in the initial dental treatment plan, led to the diagnosis of osteopetrosis. Various medical examinations co-led to the diagnosis of osteopetrosis but without genetic identification. Extractions of carious teeth, under general anesthesia, and full cover or sealants, on chair, of unaffected teeth were conducted respectively to minimize the microbial load and to prevent from osteomyelitis relapse and new caries. Two more general anesthesia sessions took place due to relapse of lower jaw osteomyelitis. Follow-up was conducted every 3 months for 2 years. CONCLUSION: Osteopetrosis' diagnosis can be triggered by its oral manifestations (rampant caries, osteonecrosis, enamel defects, malformed roots/crowns, missing teeth), for which the pediatric dentist could be the first observer. Management of these patients needs multidisciplinary approach and follow-up appointments should be very frequent.


Assuntos
Cárie Dentária , Osteomielite , Osteopetrose , Adulto , Transplante de Medula Óssea , Criança , Feminino , Humanos , Odontopediatria
7.
Artigo em Inglês | MEDLINE | ID: mdl-31333581

RESUMO

Background: Elective freezing of all embryos, followed by frozen-thawed ET cycles emerged to prevent risk of Ovarian Hyperstimulation Syndrome and to allow endometrium recovery after Controlled Ovarian Stimulation, leading to better IVF outcomes. Blastocyst Freeze-all policy can minimize the number of abnormal embryos and consequently failed ETs, but its efficacy in terms of cumulative rates has not been studied yet. Methods: A prospective cohort observational study was carried out in Assisting Nature, Center of Assisted Reproduction and Genetics, in Thessaloniki, Greece from January 2014 until December 2017. 244 patients- normal or high responders- underwent COS with recFSH and Freeze-all policy with blastocyst culture. The included patients were 18-39 years and achieved clinical pregnancy and/or live birth or had all their vitrified blastocysts transferred in subsequent frozen-thawed cycles. Women were divided into four groups (group A: 1-2 blastocysts frozen; group B: 3-4; group C: 5-6; group D ≥7 blastocysts frozen) or seven groups (group I: 1-2 blastocysts frozen, group II: 3, group III: 4, group IV: 5, group V: 6, group VI: 7; group VII: ≥8 blastocysts frozen), according to the numerical range or to the absolute number of vitrified blastocysts, respectively. Results: The main outcome of the study was the CLBR achieved by frozen-thawed ETs, according to the number of the vitrified blastocysts. Higher CLBR are expected, when at least 3 blastocysts are formed (group B: 65.2%) and at least 2 frozen-thawed ETs are performed, reaching highest rates (88%) by group D (≥7 vitrified blastocysts). Similarly, CLBR is significantly increasing with the absolute number of the vitrified blastocysts, ranging from 20%, when 1-2 blastocysts are vitrified (group I) to 82.4% when ≥8 blastocysts are available. Conclusions: A higher number of vitrified blastocysts is associated with higher CLBR in women <40 years old- normal/high responders- following Freeze-all policy. Adopting Freeze-all strategy after blastocyst culture can contribute to improve delivery outcome after IVF, in terms of CLBR. The number of the total cryopreserved blastocysts produced might reflect the quality of the oocyte and can successfully predict the pregnancy outcome. The blastulation rate can be a robust criterion to segment or not an IVF cycle.

8.
EFSA J ; 17(Suppl 2): e170905, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32626463

RESUMO

Exposure assessment is a fundamental component of the risk assessment process and has a significant contribution to the overall uncertainty of the risk estimates. The aim of the present project, implemented within the framework of the EU-FORA Fellowship, was to develop a structured approach for probabilistic modelling of the dietary exposure to chemical contaminants, which shall be used as a refined alternative to the more conservative deterministic approach or as part of a Tier 2 assessment. The fellow received training and worked in close cooperation with the project team on three case studies of contaminants in food (cadmium, acrylamide and deoxynivalenol). The modelling of the dietary intake was based on relevant EFSA Guidance and employed the Monte Carlo simulation methodology with the use of a standard software tool (Monte Carlo Risk Assessment (MCRA) platform) and/or a tailor-made risk model in the programming language R. The strengths and the limitations of every approach were explored and discussed. The conclusion from the critical comparison of the outputs was that the former can be a tool for the generation of fast preliminary estimates of the usual dietary exposure, whereas the latter may be used by the risk assessors as a more sophisticated, 'state-of-the-art' strategy, which will lead to more realistic estimates of the exposure. The outcomes of the project are being currently incorporated in a Guidance Document on probabilistic exposure assessment, which will highly contribute to more informed risk management decisions and to more effective risk communication.

9.
Open Dent J ; 11: 41-47, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28567137

RESUMO

INTRODUCTION: Injuries concerning the skull, the mouth and thus potentially involving the mouth and teeth are characterized as major public health problems due to their high prevalence and very serious functional and aesthetic consequences. Pain, aesthetic and functional problems arising from dental trauma significantly disrupt normal function, and impact, often dramatically, on young patients' quality of life. PROCEDURE: With regards to the behavior management approach to a child who has suffered a dental trauma, dentist's first step is to be to reassure child and parents. They should feel that the emergency is being properly treated on the part of the dentist and feel safe. The dentist should offer psychological support to child and parents and focus on alleviating any possible pain the child may feel. But, before that, a good level of communication with the child should be established. CONCLUSION: This can be achieved through the tell-show-do technique, a presentation of the special session's structure, the positive reinforcement method, the attention distraction method and exploiting the child's imagination. The detailed description of the treatment to be followed is crucial for reducing the child's level of stress, as well as that of the parents. Immediately after the completion of treatment, dentist should give listening time to the parents for any queries and include the child who probably wants to share their experience.

10.
Arch Dermatol Res ; 306(6): 561-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24573469

RESUMO

Basal cell carcinoma (BCC) is the most common malignant human neoplasm characterized by slow growth and virtual absence of metastases. Recently, it has become evident that along with genetic mutations epigenetic alterations play a key role in the pathogenesis of human cancer. We searched for promoter methylation of hMLH1, RASSF1A, DAPK, APC, DCR1 and DCR2 genes and BRAF mutations in BCCs in association with the clinicopathological parameters and the histological subtypes of the tumours. Fifty-two BCCs, 17 FFPE along with 35 fresh tissue samples with matching normal tissues for 26 cases were analyzed by methylation-specific PCR to assess the methylation status of hMLH1, RASSF1A, DAPK, APC, DCR1 and DCR2 genes after sodium bisulfite treatment of the tumour and normal DNA. hMLH1 and DCR1 gene expression was investigated by immunohistochemistry. BRAF mutations were studied by high resolution melting analysis. Methylation was detected at a variable frequency of 44, 33, 32.5, 32 and 14 % of DCR2, APC, DCR1, RASSF1 and DAPK promoters, respectively, whereas methylation of hMLH1 promoter was absent. No BRAF mutations were found. There was no correlation between the frequency of the promoter methylation of the above-mentioned genes and the clinicopathological features or the histological subtypes of the tumours. The relatively high frequency of RASSF1A, DCR1, DCR2 and APC promoter methylation may imply that methylation constitutes an important pathway in the tumourigenesis of BCC that could provide new opportunities in developing epigenetic therapies for BCC patients. Nevertheless, further studies are needed to establish the above-mentioned hypothesis.


Assuntos
Carcinoma Basocelular/genética , Epigênese Genética , Neoplasias Cutâneas/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteína da Polipose Adenomatosa do Colo/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinogênese/genética , Metilação de DNA , Análise Mutacional de DNA , Feminino , Proteínas Ligadas por GPI/genética , Humanos , Masculino , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL , Mutação/genética , Proteínas Nucleares/genética , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas B-raf/genética , Membro 10c de Receptores do Fator de Necrose Tumoral , Receptores Chamariz do Fator de Necrose Tumoral/genética , Proteínas Supressoras de Tumor/genética
11.
J Dermatolog Treat ; 18(3): 175-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17538807

RESUMO

Nail psoriasis is common in adult psoriatic patients and it causes serious psychological and physical distress. Topical treatments such as corticosteroids, calcipotriol, retinoids, and 5-fluorouracil have limited efficacy and are not without side effects. Relative effective systemic treatments are ciclosporin, methotrexate and acitretin, all of which have a serious toxicity potential. Biologics in the treatment of nail psoriasis have been the subject of recent research, but their cost-effectiveness is questionable. We present a case of psoriatic nail disease which improved greatly on treatment with fumaric acid esters (FAE).


Assuntos
Fármacos Dermatológicos/uso terapêutico , Fumaratos/uso terapêutico , Doenças da Unha/tratamento farmacológico , Psoríase/tratamento farmacológico , Adulto , Fármacos Dermatológicos/administração & dosagem , Fumaratos/administração & dosagem , Humanos , Masculino , Doenças da Unha/patologia , Psoríase/patologia
13.
Reprod Biol Endocrinol ; 2: 70, 2004 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-15450119

RESUMO

BACKGROUND: The objective of this randomized prospective study was to compare the efficacy of 50 mcg vaginal misoprostol and 3 mg dinoprostone, administered every nine hours for a maximum of three doses, for elective induction of labor in a specific cohort of nulliparous women with an unfavorable cervix and more than 40 weeks of gestation. MATERIAL AND METHODS: One hundred and sixty-three pregnant women with more than 285 days of gestation were recruited and analyzed. The main outcome measures were time from induction to delivery and incidence of vaginal delivery within 12 and 24 hours. Admission rate to the neonatal intensive care unit within 24 hours post delivery was a secondary outcome. RESULTS: The induction-delivery interval was significantly lower in the misoprostol group than in the dinoprostone group (11.9 h vs. 15.5 h, p < 0.001). With misoprostol, more women delivered within 12 hours (57.5% vs. 32.5%, p < 0.01) and 24 hours (98.7% vs. 91.4%, p < 0.05), spontaneous rupture of the membranes occurred more frequently (38.8% vs. 20.5%, p < 0.05), there was less need for oxytocin augmentation (65.8% vs. 81.5%, p < 0.05) and fewer additional doses were required (7.5% vs. 22%, p < 0.05). Although not statistically significant, a lower Caesarean section (CS) rate was observed with misoprostol (7.5% vs. 13.3%, p > 0.05) but with the disadvantage of higher abnormal fetal heart rate (FHR) tracings (22.5% vs. 12%, p > 0.05). From the misoprostol group more neonates were admitted to the intensive neonatal unit, than from the dinoprostone group (13.5% vs. 4.8%, p > 0.05). One woman had an unexplained stillbirth following the administration of one dose of dinoprostone. CONCLUSIONS: Vaginal misoprostol, compared with dinoprostone in the regimens used, is more effective in elective inductions of labor beyond 40 weeks of gestation. Nevertheless, this is at the expense of more abnormal FHR tracings and more admissions to the neonatal unit, indicating that the faster approach is not necessarily the better approach to childbirth.


Assuntos
Dinoprostona/farmacologia , Consentimento Livre e Esclarecido , Trabalho de Parto Induzido/métodos , Misoprostol/farmacologia , Ocitócicos/farmacologia , Paridade , Nascimento a Termo/efeitos dos fármacos , Adulto , Estudos de Coortes , Dinoprostona/administração & dosagem , Feminino , Humanos , Recém-Nascido , Misoprostol/administração & dosagem , Ocitócicos/administração & dosagem , Gravidez , Resultado da Gravidez , Fatores de Tempo
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