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1.
Chemosphere ; 301: 134672, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35472617

RESUMO

Although Glyphosate-based herbicides are often marketed as environmentally friendly and easily biodegradable, its bioavailability and risks to wildlife raise significant concerns. Among non-target organisms, earthworms which live in close contact with the soil can be directly exposed to pesticides and harmed. We investigated soil contamination and the exposure of earthworms to glyphosate, its metabolite AMPA, and glufosinate in an arable landscape in France, both in treated (i.e. temporary grasslands and cereal fields under conventional farming), and nontreated habitats (i.e. hedgerows, permanent grasslands and cereal fields under organic farming) (n = 120 sampling sites in total). Glyphosate, AMPA and glufosinate were detected in 88%, 58% and 35% of the soil samples, and in 74%, 38% and 12% of the earthworm samples, respectively. For both glyphosate and AMPA, concentrations in soils were at least 10 times lower than predicted environmental concentrations. However, the maximum glyphosate soil concentration measured (i.e., 0.598 mg kg-1) was only 2 to 3 times lower than the concentrations revealed to affect earthworms (survival and avoidance) in the literature. These compounds were found both in conventional and organic farming fields, thus supporting a recent study, and for the first time they were detected in hedgerows and grasslands. However, glyphosate and AMPA were more frequently detected in soils from cereal fields and hedgerows than in grasslands, and median concentrations measured in soils from cereal fields were significantly higher than in the two other habitats. Bioaccumulation of glyphosate and AMPA in earthworms was higher than expected according to the properties of the molecules. Our findings raised issues about the high occurrence of glyphosate and AMPA in soils from cropped and more natural areas in arable landscapes. They also highlight the potential for transfer of these molecules in terrestrial food webs as earthworms are prey for numerous animals.


Assuntos
Herbicidas , Oligoquetos , Poluentes do Solo , Aminobutiratos , Animais , Glicina/análogos & derivados , Herbicidas/análise , Herbicidas/toxicidade , Solo , Poluentes do Solo/análise , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiônico , Glifosato
2.
Proc Natl Acad Sci U S A ; 118(1)2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33443141

RESUMO

Mutagenic compounds are a potent source of human disease. By inducing genetic instability, they can accelerate the evolution of human cancers or lead to the development of genetically inherited diseases. Here, we show that in addition to genetic mutations, mutagens are also a powerful source of transcription errors. These errors arise in dividing and nondividing cells alike, affect every class of transcripts inside cells, and, in certain cases, greatly exceed the number of mutations that arise in the genome. In addition, we reveal the kinetics of transcription errors in response to mutagen exposure and find that DNA repair is required to mitigate transcriptional mutagenesis after exposure. Together, these observations have far-reaching consequences for our understanding of mutagenesis in human aging and disease, and suggest that the impact of DNA damage on human physiology has been greatly underestimated.


Assuntos
Dano ao DNA/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Transcrição Gênica/genética , Reparo do DNA/genética , Replicação do DNA/genética , Humanos , Mutagênese/genética , Mutagênese/fisiologia , Mutagênicos/toxicidade , Mutação/genética
3.
Eur J Pain ; 20(10): 1700-1709, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27172245

RESUMO

BACKGROUND AND OBJECTIVE: The clinical course of patients with sciatica is believed to be favourable, but there is conflicting evidence on the postoperative course of this condition. We aimed to investigate the clinical course of sciatica following surgery. DATABASES AND DATA TREATMENT: An electronic search was conducted on MEDLINE, EMBASE and CINAHL from inception to April 2015. We screened for prospective cohort studies investigating pain or disability outcomes for patients with sciatica treated surgically. Fractional polynomial regression analysis was used to generate pooled means and 95% confidence intervals (CI) of pain and disability up to 5 years after surgery. Estimates of pain and disability (converted to a 0-100 scale) were plotted over time, from inception to last available follow-up time. RESULTS: Forty records (39 cohort studies) were included with a total of 13,883 patients with sciatica. Before surgery, the pooled mean leg pain score was 75.2 (95% CI 68.1-82.4) which reduced to 15.3 (95% CI 8.5-22.1) at 3 months. Patients were never fully recovered in the long-term and pain increased to 21.0 (95% CI 12.5-29.5) at 5 years. The pooled mean disability score before surgery was 55.1 (95% CI 52.3-58.0) and this decreased to 15.5 (95% CI 13.3-17.6) at 3 months, and further reduced to 13.1 (95% CI 10.6-15.5) at 5 years. CONCLUSIONS: Although surgery is followed by a rapid decrease in pain and disability by 3 months, patients still experience mild to moderate pain and disability 5 years after surgery. WHAT DOES THIS REVIEW ADD?: This review provides a quantitative summary of the postoperative course of patients with sciatica. Patients with sciatica experienced a rapid reduction in pain and disability in the first 3 months, but still had mild to moderate symptoms 5 years after surgery. Although no significant differences were found, microdiscectomy showed larger improvements compared to other surgical techniques.


Assuntos
Dor Crônica/diagnóstico , Ciática/diagnóstico , Discotomia , Humanos , Medição da Dor , Estudos Prospectivos , Ciática/cirurgia , Fatores de Tempo , Resultado do Tratamento
4.
Ecotoxicology ; 25(4): 777-801, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26944290

RESUMO

Biomonitoring using birds of prey as sentinel species has been mooted as a way to evaluate the success of European Union directives that are designed to protect people and the environment across Europe from industrial contaminants and pesticides. No such pan-European evaluation currently exists. Coordination of such large scale monitoring would require harmonisation across multiple countries of the types of samples collected and analysed-matrices vary in the ease with which they can be collected and the information they provide. We report the first ever pan-European assessment of which raptor samples are collected across Europe and review their suitability for biomonitoring. Currently, some 182 monitoring programmes across 33 European countries collect a variety of raptor samples, and we discuss the relative merits of each for monitoring current priority and emerging compounds. Of the matrices collected, blood and liver are used most extensively for quantifying trends in recent and longer-term contaminant exposure, respectively. These matrices are potentially the most effective for pan-European biomonitoring but are not so widely and frequently collected as others. We found that failed eggs and feathers are the most widely collected samples. Because of this ubiquity, they may provide the best opportunities for widescale biomonitoring, although neither is suitable for all compounds. We advocate piloting pan-European monitoring of selected priority compounds using these matrices and developing read-across approaches to accommodate any effects that trophic pathway and species differences in accumulation may have on our ability to track environmental trends in contaminants.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Ambientais/metabolismo , Poluição Ambiental/estatística & dados numéricos , Aves Predatórias/metabolismo , Animais , Europa (Continente) , União Europeia , Plumas
5.
J Appl Microbiol ; 119(4): 1075-88, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26189714

RESUMO

AIMS: The main objectives were to determine the influence of secondary plant metabolites and antinutritives in lupin seeds on the fermentation performance of lactic acid bacteria and to study their ability to degrade these substances. The suitability of lupin raw materials as fermentation substrates was examined. METHODS AND RESULTS: To evaluate the fermentation performance, microbial growth, metabolite formation and substrate uptake in three different lupin substrates was monitored. On the one hand, a lupin protein isolate, which contained only trace amounts of phytochemicals was used in the study. On the other hand, the flour of Lupinus angustifolius cv. Boregine and the flour of the alkaloid rich lupin Lupinus angustifolius cv. Azuro were inoculated with Bifidobacterium animalis subsp. lactis, Pediococcus pentosaceus, Lactobacillus plantarum and Lactococcus lactis subsp. lactis. The micro-organisms showed no significant differences in the fermentation performance on the different lupin flours. Similarly, the growth of most strains on lupin protein isolate was comparable to that on the lupin flours. The fermentation with Bifidobacterium animalis subsp. lactis led to a significant decrease in flatulence causing oligosaccharides. During fermentation with Lactobacillus plantarum the phytic acid content was partially degraded. CONCLUSIONS: Neither the secondary plant metabolites nor the antinutritives of lupin flour inhibited the growth or metabolic activity of the tested micro-organisms. Therefore, lupin flour is suitable for lactic fermentation. Some strains showed the ability to degrade oligosaccharides or phytic acid. SIGNIFICANCE AND IMPACT OF THE STUDY: This work contributes to the fundamental knowledge of the metabolism of lactic acid bacteria during fermentation of lupin substrates. Fermentation of lupin raw materials could be used to improve the nutritional value of the substrates due to the reduction of antinutritives.


Assuntos
Bifidobacterium/metabolismo , Lactobacillus plantarum/metabolismo , Lactococcus lactis/metabolismo , Lupinus/microbiologia , Pediococcus/metabolismo , Fermentação , Farinha/microbiologia , Ácido Láctico/metabolismo , Valor Nutritivo , Ácido Fítico/metabolismo
6.
Environ Int ; 67: 12-21, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24632328

RESUMO

Biomonitoring using raptors as sentinels can provide early warning of the potential impacts of contaminants on humans and the environment and also a means of tracking the success of associated mitigation measures. Examples include detection of heavy metal-induced immune system impairment, PCB-induced altered reproductive impacts, and toxicity associated with lead in shot game. Authorisation of such releases and implementation of mitigation is now increasingly delivered through EU-wide directives but there is little established pan-European monitoring to quantify outcomes. We investigated the potential for EU-wide coordinated contaminant monitoring using raptors as sentinels. We did this using a questionnaire to ascertain the current scale of national activity across 44 European countries. According to this survey, there have been 52 different contaminant monitoring schemes with raptors over the last 50years. There were active schemes in 15 (predominantly western European) countries and 23 schemes have been running for >20years; most monitoring was conducted for >5years. Legacy persistent organic compounds (specifically organochlorine insecticides and PCBs), and metals/metalloids were monitored in most of the 15 countries. Fungicides, flame retardants and anticoagulant rodenticides were also relatively frequently monitored (each in at least 6 countries). Common buzzard (Buteo buteo), common kestrel (Falco tinnunculus), golden eagle (Aquila chrysaetos), white-tailed sea eagle (Haliaeetus albicilla), peregrine falcon (Falco peregrinus), tawny owl (Strix aluco) and barn owl (Tyto alba) were most commonly monitored (each in 6-10 countries). Feathers and eggs were most widely analysed although many schemes also analysed body tissues. Our study reveals an existing capability across multiple European countries for contaminant monitoring using raptors. However, coordination between existing schemes and expansion of monitoring into Eastern Europe is needed. This would enable assessment of the appropriateness of the EU-regulation of substances that are hazardous to humans and the environment, the effectiveness of EU level mitigation policies, and identify pan-European spatial and temporal trends in current and emerging contaminants of concern.


Assuntos
Monitoramento Ambiental/estatística & dados numéricos , Poluentes Ambientais/análise , Aves Predatórias/fisiologia , Animais , Europa (Continente) , Plumas/química , Aves Predatórias/classificação , Inquéritos e Questionários , Zigoto/química
7.
Ultrasonics ; 50(2): 122-6, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19879617

RESUMO

This work addresses three key subjects to the image quality with phased arrays: timing accuracy, beamforming strategy and post-processing for increased resolution and suppression of grating and side lobes. Timing accuracy is achieved by defining a modular and scalable architecture which guarantees low timing errors, whatever is the system size. The proposed beamforming methodology follows the progressive focusing correction technique, which keeps low focusing errors, provides a high information density and has a simple implementation for real-time imaging in modular architectures. Then, phase coherence imaging is defined to suppress grating and sidelobe indications, simultaneously increasing the lateral resolution.

8.
Sci Total Environ ; 407(21): 5564-77, 2009 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-19665168

RESUMO

The contamination of the topsoil of 262 woody habitats around a former lead smelter in the North of France was assessed. In this urbanized and industrialized area, these kinds of habitats comprise of hedges, groves, small woods, anthropogenic creations and one large forest. Except for the latter, which is 3 km away, these woody habitat soils often present a high anthropization degree (a significant amount of pebbles and stones related to human activities) with a high metal contamination. In the studied woody habitat topsoils, Cd, Pb and Zn concentrations largely exceeded those of agricultural topsoils located in the same environmental context. Therefore, atmospheric emissions from the smelter are not the only cause of the high contamination of the woody habitat soils. This last one is related to the nature and the contamination level of deposit in relation with human activities (rubbles, slag, soils, etc). With regard to the results obtained with chemical extractions, the mobility of Cd, Pb and Zn in these soils is also greater than in agricultural soils. In the forest, pollutant solubility is increased by soil acidic pH. The variability of the physico-chemical parameters and the high metal contamination of the topsoils are the main characteristics of the woody habitats located around the former smelter. Although never taken into account during risk assessment, the disturbance of these environmental components could have important biogeochemical impacts (nutrients and metal cycles). Moreover, any modification of the soils' use could potentially cause mobilization and transfer of the pollutants to the biosphere. Six years after the closure of the smelter, and as social and economic pressures considerably increase in this area, the study of these peculiar ecosystems is necessary to understand and predict the bioavailability, transfer, bioaccumulation and effects of pollutants in food chains.


Assuntos
Monitoramento Ambiental , Resíduos Industriais/análise , Chumbo/análise , Metalurgia , Poluentes do Solo/análise , Cádmio/análise , Cádmio/química , Fracionamento Químico , França , Chumbo/química , Medição de Risco , Árvores , Zinco/análise , Zinco/química
9.
J Eur Acad Dermatol Venereol ; 23(5): 550-5, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19415804

RESUMO

BACKGROUND: Photodynamic therapy (PDT) using methyl aminolevulinate (MAL) is an effective first-line treatment for actinic keratoses. A reduced incubation period may have practical advantages. OBJECTIVE: This study aims to evaluate the effect of incubation time (1 vs. 3 h), MAL concentration (160 mg/g vs. 80 mg/g) and lesion preparation in the setting of MAL-PDT for treatment of actinic keratosis (AK). DESIGN: Open, randomized, parallel-group multicentre study. SETTING: Outpatient dermatology clinics. SUBJECTS: One hundred and twelve patients with 384 previously untreated AK. Most lesions (87%) were located on the face and scalp and were thin (55%) or moderately thick (34%). METHODS: Lesions were debrided, and MAL cream (160 mg/g or 80 mg/g) was applied before illumination with red light (570-670 nm; light dose, 75 J/cm2). Patients were followed up at 2 and 3 months. Sixty patients (54%) were re-treated and assessed at 6 months. MAIN OUTCOME: Complete lesion response rates 3 and 12 months after last treatment. RESULTS: For lesions on the face/scalp, lesion complete response rates were 78% for thin AK and 74% for moderately thick AK lesions after 1 h vs. 96% and 87% after 3 h incubation with MAL 160 mg/g. Lesion recurrence rates at 12 months after two treatments were similar [19% (3 of 16) with 1 h vs. 17% (3 of 18) with 3 h 160 mg/kg MAL-PDT] and lower than for 80 mg/g MAL-PDT (44-45%). CONCLUSION: MAL-PDT using a 1-h incubation may be sufficient for successful treatment of selected AK lesions.


Assuntos
Ácido Aminolevulínico/análogos & derivados , Ceratose Actínica/tratamento farmacológico , Fotoquimioterapia , Fármacos Fotossensibilizantes/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Ácido Aminolevulínico/administração & dosagem , Ácido Aminolevulínico/efeitos adversos , Ácido Aminolevulínico/uso terapêutico , Cosméticos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/efeitos adversos , Recidiva , Resultado do Tratamento
11.
Artigo em Inglês | MEDLINE | ID: mdl-18519225

RESUMO

A simple input protection circuit for ultrasound pulse-echo applications is described. Its performance is analyzed with regard to other widely used arrangements. Besides the primary function of showing high impedance during the transducer excitation time and a low impedance path to the amplifier in reception, issues of harmonic distortion, insertion losses, bandwidth, power dissipation, transient response, and noise are addressed. It is shown that the proposed circuit has many advantages, operating without any control signals or bias voltages. It is small and can be considered a good general-purpose protection circuit alternative.


Assuntos
Amplificadores Eletrônicos , Desenho Assistido por Computador , Eletrônica/instrumentação , Análise de Falha de Equipamento/instrumentação , Falha de Equipamento , Ultrassonografia/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento/métodos
12.
Hautarzt ; 57(3): 228, 230-2, 234-6, 2006 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-16240153

RESUMO

50 Patients with chronic renal failure undergoing hemodialysis with or without porphyria cutanea tarda (PCT)-like skin changes were investigated. The total porphyrin amount in erythrocytes, plasma and dialysate and the distribution of porphyrin metabolites in plasma and dialysate were measured. In plasma, the group of patients with skin changes (referred as PCU = porphyria cutanea uremica) showed significantly increased uroporphyrin levels as compared to the non-symptomatic group. In addition, significant differences concerning the ratio uro-/coproporphyrin in plasma were shown: non-symptomatic patients with 0.87, as opposed to the PCU group with 3.7. Considerable differences between the level of vitamin ingestion were identified between the groups. Patients with PCU took distinctly less vitamins C, E and B than patients without symptoms.


Assuntos
Porfiria Cutânea Tardia/prevenção & controle , Uremia/prevenção & controle , Vitaminas/administração & dosagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ácido Ascórbico/administração & dosagem , Coproporfirinas/sangue , Relação Dose-Resposta a Droga , Feminino , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/terapia , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Porfiria Cutânea Tardia/sangue , Porfiria Cutânea Tardia/diagnóstico , Valores de Referência , Diálise Renal , Fatores de Risco , Uremia/sangue , Uremia/diagnóstico , Uroporfirinas/sangue , Complexo Vitamínico B/administração & dosagem , Vitamina E/administração & dosagem
13.
MMW Fortschr Med ; 146(26): 51-4, 2004 Jun 24.
Artigo em Alemão | MEDLINE | ID: mdl-15529693

RESUMO

Pedographic systems are now in use in many research centers and hospitals throughout the world. The platform system permits rapid and accurate static and dynamic measurement of the local pressure loading on the plantar surface of the foot, and also permits a functional assessment of the roll-over process in the bare foot. The in-shoe system employing an insole measures the pressure distribution within an orthopedic shoe and enables an accurate comparison of the loading situation before and after fitting. As an additional diagnostic tool, pedography improves preventive measures and the quality of the orthopedic treatment of the diabetic foot.


Assuntos
Pé Diabético/diagnóstico , Marcha/fisiologia , Suporte de Carga/fisiologia , Fenômenos Biomecânicos , Pé Diabético/fisiopatologia , Pé Diabético/reabilitação , Neuropatias Diabéticas/diagnóstico , Neuropatias Diabéticas/fisiopatologia , Neuropatias Diabéticas/reabilitação , Humanos , Aparelhos Ortopédicos , Sapatos , Transdutores de Pressão
14.
Ultrasonics ; 42(1-9): 797-801, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15047386

RESUMO

Flaw detection near the interface surface is a common problem in many pulse-echo NDT applications due to interference with the interface echo, orders of magnitude above the flaw echoes. Several digital signal processing techniques like deconvolution, Hilbert transform and cepstrum analysis have been proposed to improve axial resolution. However, they require strict linearity, which takes a large portion of the system dynamic range just to fit the interface echo, thus reducing the dynamic range available for flaw detection. This work presents a new alternative based on the time-domain phase analysis of the received signals. Differently from conventional approaches, it works quite well with saturated signals resulting when a high gain is applied to detect small flaws. These can be detected in a range of a fraction of one wavelength from the interface surface, even using narrow-band transducers, as it has been experimentally verified. The method can be easily hardware implemented for real-time processing.

15.
Br J Dermatol ; 149(6): 1242-9, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14674903

RESUMO

BACKGROUND: Conventional treatment of basal cell carcinoma (BCC) causes morbidity and/or disfigurement in some patients because of the location (e.g. mid-face) and size of the lesion. OBJECTIVES: Following reports that such difficult-to-treat BCC lesions have been treated successfully with topical methyl aminolaevulinate (MAL) photodynamic therapy (PDT), a multicentre study was performed to determine the response of such BCC to MAL-PDT. METHODS: An open, uncontrolled, prospective, multicentre study was conducted comprising patients with superficial and/or nodular BCC who were at risk of complications, poor cosmetic outcome, disfigurement and/or recurrence using conventional therapy. Patients were given one or two cycles within 3 months of topical MAL-PDT, each consisting of two treatments 1 week apart. Tumour response was assessed clinically at 3 months after the last PDT, with histological confirmation of all lesions in clinical remission. The cosmetic outcome was rated. Patients with a BCC in remission will be followed up for 5 years for recurrence, of which the 24-month follow-up is reported here. Ninety-four patients with 123 lesions were enrolled and treated with MAL-PDT at nine European primary care and referral university hospitals. An independent blinded study review board (SRB) retrospectively excluded nine patients and a total of 15 lesions from the efficacy analysis, for not having a difficult-to-treat BCC according to the protocol. RESULTS: The lesion remission rate at 3 months was 92% (45 of 49) for superficial BCC, 87% (45 of 52) for nodular BCC, and 57% (four of seven) for mixed BCC, as assessed by clinical examination, and 85% (40 of 47), 75% (38 of 51), and 43% (three of seven), respectively, as assessed by histological examination and verified by the SRB. At 24 months after treatment, the overall lesion recurrence rate was 18% (12 of 66). The cosmetic outcome was graded as excellent or good by the investigators in 76% of the cases after 3 months follow-up, rising to 85% at 12 months follow-up, and 94% at 24 months follow-up. CONCLUSIONS: Topical MAL-PDT is effective in treating BCC at risk of complications and poor cosmetic outcome using conventional therapy. MAL-PDT preserves the skin and shows favourable cosmetic results.


Assuntos
Ácido Aminolevulínico/análogos & derivados , Ácido Aminolevulínico/administração & dosagem , Carcinoma Basocelular/tratamento farmacológico , Fotoquimioterapia , Fármacos Fotossensibilizantes/administração & dosagem , Neoplasias Cutâneas/tratamento farmacológico , Administração Tópica , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Resultado do Tratamento
16.
Exp Dermatol ; 12(6): 843-8, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14714565

RESUMO

Porphyria cutanea tarda (PCT) is the most frequent porphyria in humans. The familial type is in contrast to the sporadic type due to an inherited defect of the uroporphyrinogen-II-decarboxylase (URO-D) and both types need additional porphyrinogens to lead to the clinical manifestation of the disease. Various factors such as xenobiotics (i.e. polycyclic aromatic hydrocarbons), alcohol, hormones and viral liver infections (hepatitis B and C) are known to induce porphyria. Cytochrome p450 enzymes play a crucial role in the metabolism of porphyrogens and therefore might have an important influence on the pathogenesis of hepatic porphyrias. Association of CYP1A2 polymorphisms with susceptibility to both types of PCT has already been described in Danish patients. We investigated 65 caucasian patients with PCT in comparison to a healthy control group concerning the tpe of PCT and the cytochrome p4501A1 polymorphisms (m1, m2 and m4) using polymerase chain reaction (PCR) and a restriction fragment length polymorphism. We found an increased incidence of the m4 polymorphism in the familial type of PCT (odds ratio 5.5, P-value 0.01), whereas the m1 and m2 mutations, might be provoked by a higher susceptibility to porphyrogens via the cytochrome p4501A1 m4 polymorphism.


Assuntos
Citocromo P-450 CYP1A1/genética , Polimorfismo Genético , Porfiria Cutânea Tardia/genética , Alelos , Sistema Enzimático do Citocromo P-450/metabolismo , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Razão de Chances , Polimorfismo de Fragmento de Restrição , Porfiria Cutânea Tardia/etnologia , Porfirinas/urina , Uroporfirinogênio Descarboxilase/deficiência , Uroporfirinogênio Descarboxilase/genética , População Branca
17.
Ultrasonics ; 40(1-8): 599-604, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12160008

RESUMO

The beamforming process requires a high delay resolution to avoid the deteriorating effects of the delay quantization lobes on the image dynamic range and signal to noise ratio. Wideband transducers require delay resolutions in the order of 1/16 the signal period. If oversampling is used to achieve this timing resolution, a huge data volume has to be acquired and processed in real time. This is usually avoided by sampling just above the Nyquist rate and interpolating to achieve the required delay resolution. However this increases the hardware complexity. Baseband sampling has been alternatively proposed with sampling rates as low as the transducer frequency or even lower. This approach uses two A/D converters and processing chains for every channel, thus doubling the hardware requirements. Quadrature sampling can be used instead with a single A/D converter, but the sampling rate must be a multiple of four times the transducer frequency, decreasing the application flexibility. Furthermore, it produces relatively high errors in the detected envelope if wideband transducers are used. This work presents a new approach, the selective sampling technique (SST), which keeps the lowest sampling rate required by the imaging process or the signal bandwidth (whatever is larger) and, at the same time, provides a high delay resolution to keep the highest image dynamic range. The SST is based on a second order sampling process which, differently from the mentioned approaches, does not pose any constraints in the time interval between samples and produce lower errors in the detected envelope. The hardware requirements are low (a single A/D converter and processing chain for every transducer element), working at the lowest data rate compatible with the Nyquist criterion, thus reducing the data bandwidth. Furthermore, the sampling points can be also freely chosen, so that the SST simplify the usually required scan conversion process to a simple linear interpolation easily carried out by software in real-time.

18.
J Eur Acad Dermatol Venereol ; 16(2): 162-3, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12046824

RESUMO

Pigmentary abberations of the skin, mucosa and epidermal appendages are common side-effects after systemic treatment with chemotherapeutic agents. These pigment changes appear in different patterns and are partly quite typical for the applied chemotherapeutic drug. The pathogenesis of the different skin pigmentations are not well known. The most often discussed causes are the stimulation of melanocytes, involvement of the tyrosinase enzyme system and thrombophlebitis with postinflammatory hyperpigmentation by the aggressive substances. Nail discolorations are mainly due to direct toxic effects and stimulation of the matrix melanocytes. We report a rare event of supravenous hyperpigmentation, transverse leuconychia and melanonychia after chemotherapy of a patient suffering from Hodgkin's disease.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Doença de Hodgkin/tratamento farmacológico , Hiperpigmentação/induzido quimicamente , Doenças da Unha/etiologia , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Seguimentos , Doença de Hodgkin/diagnóstico , Humanos , Hiperpigmentação/diagnóstico , Masculino , Doenças da Unha/diagnóstico , Medição de Risco , Índice de Gravidade de Doença , Extremidade Superior , Veias
19.
J Photochem Photobiol B ; 65(1): 29-34, 2001 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11748002

RESUMO

In fluorescence diagnosis and photodynamic therapy of neoplastic tissues 5-aminolevulinic acid is used to synthesize endogenous porphyrins as photosensitizers. The efficacy of neoplastic tissues to fluorescence diagnosis and photodynamic therapy is thought to be dependent on the total level of intralesional formed porphyrins. The available profiles of porphyrin metabolites in normal and in neoplastic cell lines after administration of 5-aminolevulinic acid vary considerably. Thus, this is the first in-vitro study which compares the porphyrin biosynthesis in normal skin cells (HaCaT, fibroblasts) with melanoma cells (Bro, SKMel-23, SKMel-28). After incubation with 1 mM 5-aminolevulinic acid, kinetics of porphyrin levels and metabolites were determined in the cells and the corresponding supernatants. Exogenous 5-aminolevulinic acid induced porphyrin formation in all cells with maximum values after an incubation period of 16-36 h. Increase of porphyrin levels varied from 10- to 80-fold (SKMel-28>HaCaT>fibroblasts>SKMel-23>>Bro) with minimum 1.5 times higher levels of porphyrins in the supernatants than in the cells. In cells and supernatants protoporphyrin and coproporphyrin were the predominantly formed porphyrin metabolites. Metastatic melanoma cells (SKMel-23, SKMel-28) accumulated much higher porphyrin levels than primary melanoma cells (Bro). In conclusion, by optimizing the treatment modalities, especially the light source, topical photodynamic therapy (PDT) could become a treatment alternative of melanoma metastases in progressive disease.


Assuntos
Ácido Aminolevulínico/metabolismo , Fármacos Fotossensibilizantes/metabolismo , Porfirinas/biossíntese , Linhagem Celular Transformada , Humanos , Neoplasias Cutâneas , Células Tumorais Cultivadas
20.
Praxis (Bern 1994) ; 90(43): 1869-73, 2001 Oct 25.
Artigo em Francês | MEDLINE | ID: mdl-11712494

RESUMO

The indication for a radiological examination of a patient with low back pain by CT or MRI scans is based on age, medical history and clinical findings. The result of morphological (and possibly structural) tests should be consistent with the clinical findings. In fact, the scans often do not provide very powerful evidence. The elderly patient frequently has permanent deformations or primary or secondary malignant bone lesions and therefore requires special tests.


Assuntos
Deslocamento do Disco Intervertebral/diagnóstico , Dor Lombar/etiologia , Vértebras Lombares/patologia , Imageamento por Ressonância Magnética , Doenças da Coluna Vertebral/diagnóstico , Tomografia Computadorizada por Raios X , Diagnóstico Diferencial , Humanos
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