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1.
Orphanet J Rare Dis ; 19(1): 26, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38279137

RESUMO

BACKGROUND: Hereditary leiomyomatosis and renal cell cancer syndrome is a rare autosomal dominant hereditary syndrome. Previously, we published the largest cohort of FH mutation carriers in Spain and observed a highly recurrent missense heterozygous variant, FH(NM_000143.4):c.1118A > G p.(Asn373Ser), in 104 individuals from 31 apparently unrelated families. Here, we aimed to establish its founder effect and characterize the associated clinical phenotype. RESULTS: Haplotype analysis confirmed that families shared a common haplotype (32/38 markers) spanning 0.61-0.82 Mb, indicating this recurrent variant was inherited from a founder ancestor. Cutaneous and uterine leiomyomatosis were diagnosed in 64.6% (64/99) and 98% (50/51) of patients, respectively, and renal cell cancer was present in 10.4% (10/96). The pathogenic FH_c.1118A > G variant is a Spanish founder mutation that originated 12-26 generations ago. We estimate that the variant may have appeared between 1370 and 1720. Individuals carrying this founder mutation had similar frequency of renal cell cancer and a higher frequency of renal cysts and leiomyomas than those in other cohorts of this syndrome. CONCLUSIONS: In the Spanish province of Alicante there is a high prevalence of HLRCC because of the founder mutation FH c.1118A > G; p.(Asn373Ser). The characterization of founder mutations provides accurate and specific information regarding their penetrance and expressivity. In individuals with suspected HLRCC from the province of Alicante, genetic testing by direct analysis of the founder FH c.1118A > G; p.(Asn373Ser) mutation may be a faster and more efficient diagnostic tool compared with complete gene sequencing.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Leiomiomatose , Síndromes Neoplásicas Hereditárias , Neoplasias Cutâneas , Neoplasias Uterinas , Feminino , Humanos , Leiomiomatose/genética , Leiomiomatose/patologia , Neoplasias Renais/genética , Neoplasias Cutâneas/patologia , Mutação/genética , Síndrome
2.
Talanta ; 230: 122314, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33934779

RESUMO

The preservation of the integrity of artworks and cultural heritage items during characterization and conservation operations is of high priority, therefore, the application of non-invasive techniques is commonly suggested and recommended. Nonlinear optical microscopies (NLOM), based on the use of tightly focused pulsed femtosecond lasers, are emerging techniques for structural and chemical analysis of heritage objects with micrometric lateral and axial resolution. The results obtained with a set of optical and spectroscopic techniques for the chemical and physical characterization of grisaille paint layers on historical stained glasses, from different chronologies and provenance in Spain, are presented in this work. Optical behaviour and chemical composition were investigated by NLOM, using a laboratory set-up in the modality of Multi-Photon Excitation Fluorescence (MPEF), and by a multi-analytical combination of Field Emission Scanning Electron Microscopy-Energy Dispersive X-ray Spectrometry (FESEM-EDS), Laser Induced Breakdown Spectrosocopy (LIBS) and Laser Induced Fluorescence (LIF). Thicknesses values of the historical grisaille paint layers measured with MPEF were compared with those retrieved through FESEM, showing significant consistency and agreement. Under proper conditions, analysis via MPEF microscopy avoids the photochemical and physical damage to the examined materials, thus ensuring their preservation. This approach paves the way for future in-situ, non-invasive stratigraphic investigations on cultural heritage objects.

3.
Cancers (Basel) ; 12(11)2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33167498

RESUMO

Hereditary leiomyomatosis and renal cell cancer syndrome (HLRCC) is a very rare hereditary disorder characterized by cutaneous leiomyomas (CLMs), uterine leiomyomas (ULMs), renal cysts (RCys) and renal cell cancers (RCCs). We aimed to describe the genetics, clinical features and potential genotype-phenotype associations in the largest cohort of fumarate hydratase enzyme mutation carriers known from Spain using a multicentre, retrospective study of individuals with a genetic or clinical diagnosis of HLRCC. We collected clinical information from medical records, analysed genetic variants and looked for genotype-phenotype associations. Analyses were performed using R 3.6.0. software. We included 197 individuals: 74 index cases and 123 relatives. CLMs were diagnosed in 65% of patients, ULMs in 90% of women, RCys in 37% and RCC in 10.9%. Twenty-seven different pathogenic variants were detected, 12 (44%) of them not reported previously. Patients with missense pathogenic variants showed higher frequencies of CLMs, ULMs and RCys, than those with loss-of-function variants (p = 0.0380, p = 0.0015 and p = 0.024, respectively). This is the first report of patients with HLRCC from Spain. The frequency of RCCs was lower than those reported in the previously published series. Individuals with missense pathogenic variants had higher frequencies of CLMs, ULMs and RCys.

4.
Phys Chem Chem Phys ; 20(25): 16956-16965, 2018 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-29897078

RESUMO

Femtosecond laser ablation of solids is known to produce ejection of material to a large extent composed of particles of nanometer dimensions for a broad variety of targets. This work explores the ultrashort laser ablation of metal targets (Ag, Cu, Al, Mn) through non-conventional diagnostics based on the nonlinear response of the transient medium created upon ablation. The full temporal mapping of the nonlinear response constitutes a useful flag that signals the abundance of clusters and nanoparticles in the plume. The use of this method for diagnosis has allowed us to perform direct observation of middle-sized aggregates that are extremely elusive with other techniques. Additionally, one crucial and seldom explored parameter in this context has been identified: the ablation laser spot size. Optimum conditions for overall nanoparticle generation as well as relative nanoparticle/cluster/atom ratios have been found.

5.
Phys Chem Chem Phys ; 19(34): 22836-22843, 2017 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-28812067

RESUMO

The nonlinear optical microscopy (NLM) modalities of Multi-Photon Excited Fluorescence (MPEF) and Third Harmonic Generation (THG) have been combined in this work to characterize as a function of depth with micrometric resolution the type and extent of morphological and photochemical modifications that take place upon ultraviolet (UV) pulsed laser removal of a dammar varnish layer applied on a photosensitive substrate. The latter consists on a layer of the synthetic polymer poly-methyl methacrylate doped with a photosensitizer, the aromatic compound 1,4-di[2-(5-phenyloxazolyl)] benzene, that strongly fluoresces upon UV light illumination. A number of laser conditions for partial or total elimination of the varnish coating were explored, namely different wavelengths (266, 248 and 213 nm) and pulse durations, in the nanosecond, picosecond and femtosecond ranges. Changes in the MPEF signals upon laser ablation of the outermost varnish layer successfully signpost photochemical modifications of the varnish or of the photosensitive under-layer, and their dependence with the laser ablation parameters, i.e., wavelength and pulse duration. In turn, THG signals mark the presence of layer boundaries and the reduction by laser ablation of the thickness of the varnish coating. The obtained MPEF and THG data are complemented by morphological observation by optical microscopy and measurements of laser induced fluorescence and micro-Raman spectra of the samples before and after laser ablation at the selected laser irradiation conditions. The results acquired through these non-destructive NLM imaging techniques serve to understand the phenomena that are induced upon laser ablation and to determine the best operating conditions that ensure controlled removal of the varnish with minimal morphological and chemical modifications to the under-layers. This research is of direct application to the UV pulsed laser cleaning of paintings and demonstrates the potential of NLM as a novel assessment tool for non-destructive, on line monitoring of the laser cleaning process.

6.
BMC Fam Pract ; 16: 154, 2015 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-26498043

RESUMO

BACKGROUND: In a context of increasing demand and pressure on the public health expenditure, appropriateness of colonoscopy indications is a topic of discussion. The objective of this study is to evaluate the appropriateness of colonoscopy requests performed in a primary care (PC) setting in Catalonia. METHODS: Cross-sectional descriptive study. Out-patients >14 years of age, referred by their reference physicians from PC or hospital care settings to the endoscopy units in their reference hospitals, to undergo a colonoscopy. Evaluation of the appropriateness of 1440 colonoscopy requests issued from January to July 2011, according to the EPAGE-II guidelines (European Panel on the Appropriateness of Gastrointestinal Endoscopy). RESULTS: The most frequent indications of diagnostic suspicion requests were: rectal bleeding (37.46 %), abdominal pain (26.54 %), and anaemia study (16.78 %). The most frequent indications of disease follow-up were adenomas (58.1 %), and CRC (31.16 %). Colonoscopy was appropriate in 73.68 % of the cases, uncertain in 16.57 %, and inappropriate in 9.74 %. In multivariate analysis, performed colonoscopies reached an OR of 9.9 (CI 95 % 1.16-84.08) for qualifying as appropriate for colorectal cancer (CRC) diagnosis, 1.49 (CI 95 % 1.1-2.02) when requested by a general practitioner, and 1.09 (CI 95 % 1.07-1.1) when performed on women. CONCLUSIONS: Appropriateness of colonoscopy requests in our setting shows a suitable situation in accordance with recognized standards. General practitioners contribute positively to this appropriateness level. It is necessary to provide physicians with simple and updated guidelines, which stress recommendations for avoiding colonoscopy requests in the most prevalent conditions in PC.


Assuntos
Colonoscopia/estatística & dados numéricos , Procedimentos Desnecessários/estatística & dados numéricos , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Encaminhamento e Consulta/estatística & dados numéricos , Espanha
7.
Methods Mol Biol ; 1072: 303-13, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24136531

RESUMO

Medicago truncatula has become the focus of systems biology research for improved legume crop breeding. In plant systems biology, several comparative studies have been carried out using liquid chromatography shotgun mass spectrometry (LC-MS/MS) and database-dependent protein identification analyses in combination with the spectral count for relative quantification. In order to receive optimal protein identification rates and spectral count quantification, data-dependent tandem mass spectrometry with LC separation of more than 1 h is required. Thus LC-MS/MS analyses time is the bottleneck for high-throughput research of experiments with high sample number.We describe a novel method, called full-scan (FS) selective peptide extraction, that allows for comparative quantification of target peptides combined with a significant reduction in LC-MS analysis time. In future, it will be a useful tool to detect (15)N-labeled selected peptide patterns for the targeted analysis of protein turnover and synthesis. We provide a first reference library of selected target peptides generated for M. truncatula leaf tissue. These peptides are also suitable candidates for selective reaction monitoring approaches.


Assuntos
Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Medicago truncatula/metabolismo , Peptídeos/isolamento & purificação , Proteômica/métodos , Biologia de Sistemas/métodos , Sequência de Aminoácidos , Dados de Sequência Molecular , Peptídeos/química , Folhas de Planta/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-23201568

RESUMO

In this study, the reaction of widely used artist's pigments in raw form to pulsed laser radiation of different wavelengths and pulse duration was investigated. Vermilion, lead chromate and malachite (in the form of pellets) were irradiated using laser pulses of 500 fs at 248 nm, and pulses of 150 ps and 15 ns at 1064 and 213 nm. Optical microscopy, colorimetry, spectrofluorimetry, micro-Raman spectroscopy and X-ray photoelectron spectroscopy were employed to characterize the physicochemical changes induced to the pigments. Change of crystalline phase was identified for vermilion while reduction processes take place for lead chromate and malachite. It was found that these effects were minimized by application of ultraviolet ultrashort pulses (of femtosecond and picosecond duration) as compared with changes occurring by pulsed infrared irradiation (of both picosecond and nanosecond duration). The results presented are discussed in relation to previous research on painted mock-ups in order to elucidate the role and significance of the binding media in the laser induced discoloration of painted surfaces and thus to propose optimum laser cleaning practices.


Assuntos
Corantes/química , Pinturas , Cromatos/química , Colorimetria , Cristalização , Lasers , Chumbo/química , Microscopia , Compostos Organometálicos/química , Espectroscopia Fotoeletrônica , Análise Espectral Raman
10.
Langmuir ; 28(20): 7938-45, 2012 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-22524535

RESUMO

Here we present a precise morphological description of laser-induced periodic surface structures (LIPSS) nanofabricated on spin-coated poly(trimethylene terephthalate) (PTT) films by irradiation with 266 nm, 6 ns laser pulses and by using a broad range of fluences and number of pulses. By accomplishing real and reciprocal space measurements by means of atomic force microscopy and grazing incidence wide- and small-angle X-ray scattering respectively on LIPSS samples, the range of optimum structural order has been established. For a given fluence, an increase in the number of pulses tends to improve LIPSS in PTT. However, as the pulse doses increase above a certain limit, a distortion of the structures is observed and a droplet-like morphology appears. It is proposed that this effect could be related to a plausible decrease of the molecular weight of PTT due to laser-induced chain photo-oxidation by irradiation with a high number of pulses. A concurrent decrease in viscosity enables destabilization of LIPSS by the formation of droplets in a process similar to surface-limited dewetting.

12.
Anal Bioanal Chem ; 402(4): 1433-41, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21866402

RESUMO

This article reports on a compositional investigation of stone patinas: thin colored layers applied for protective and/or aesthetic purposes on architectural or sculptural substrates of cultural heritage. The analysis and classification of patinas provide important information of historic and artistic interest, as their composition reflects local practices, the availabilities of different materials, and the development of technological knowledge during specific historical periods. Model patinas fabricated according to traditional procedures and applied onto limestone, and a historic patina sample from the main façade of the San Blas Monastery in Lerma (a village in the province of Burgos, Spain), were analyzed by laser-induced fluorescence and Fourier transform Raman spectroscopy. The results obtained demonstrate the ability of these two analytical techniques to identify the key components of each formulation and those of the reaction products which result from the chemical and mineralogical transformations that occur during aging, as well as to provide information that can aid the classification of different types of patinas.

13.
Phys Chem Chem Phys ; 13(22): 10755-61, 2011 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-21547285

RESUMO

Third and fifth harmonic generation of an IR (1.064 µm) pulsed laser has been produced in ablation plasmas of the wide bandgap semiconductors CdS and ZnS. The study of the temporal behaviour of the harmonic emission has revealed the presence of distinct compositional populations in these complex plasmas. Species ranging from atoms to nanometre-sized particles have been identified as emitters, and their nonlinear optical properties can be studied separately due to strongly differing temporal behaviour. At short distances from the target (<1 mm), atomic species are mostly responsible for harmonic generation at early times (<500 ns), while clusters and nanoaggregates mostly contribute at longer times (>1 µs). Harmonic generation thus emerges as a powerful and universal technique for ablation plasma diagnosis and as a tool to determine the nonlinear optical susceptibility of ejected clusters or nanoparticles.

14.
Pathology ; 43(3): 228-33, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21436632

RESUMO

BACKGROUND: The incidence of colorectal cancer (CRC) in Peru has been increasing, and no data have been published on the molecular features. We explored the most relevant genetic events involved in colorectal carcinogenesis, with clinical implications. METHODS: Using immunohistochemistry for mismatch-repair (MMR) proteins (MLH1, MSH2, MSH6, and PMS2) and microsatellite instability analysis, we evaluated the status of 90 non-selected CRC Peruvian patients followed in a nationwide reference hospital for cancer (INEN, Lima). Tumours with loss of hMLH1 were evaluated further for hMLH1 promoter hypermethylation and all cases were evaluated for the presence of KRAS and BRAF-V600E mutations. RESULTS: MMR deficiency was found in 35 (38.8%) patients. We identified an unexpected association between MMR deficiency and older age. Among the 14 cases with loss of MLH1, 10 samples exhibited hypermethylation. Of the 90 cases evaluated, 15 (16.7%) carried KRAS mutations; we found one previously unreported mutation (G13R). CONCLUSIONS: Peruvian CRC tumours exhibited the highest prevalence of MMR deficiency reported to date. The expected hereditary component was also high. The age of onset of these MMR deficient tumours was greater than that observed for non-MMR deficient cases, suggesting the ineffectiveness of the Bethesda criteria for Lynch syndrome screening in Peru. Prospective studies are warranted to define the molecular characteristics of CRC in this population.


Assuntos
Neoplasias Colorretais/genética , Reparo de Erro de Pareamento de DNA/genética , Distúrbios no Reparo do DNA/genética , Mutação , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Pareamento Incorreto de Bases , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/metabolismo , Distúrbios no Reparo do DNA/metabolismo , Distúrbios no Reparo do DNA/patologia , Proteínas de Ligação a DNA/metabolismo , Feminino , Inativação Gênica , Humanos , Imuno-Histoquímica , Masculino , Metilação , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas p21(ras) , Adulto Jovem , Proteínas ras/metabolismo
16.
J Agric Food Chem ; 58(24): 12822-32, 2010 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-21090568

RESUMO

Responses to Mycosphaerella pinodes in pea were studied by using a proteomics approach. Two-dimensional electrophoresis (2-DE) was used in order to compare the leaf proteome of two pea cultivars displaying different phenotypes (susceptible and partial resistance to the fungus), as well as in response to the inoculation. Multivariate statistical analysis identified 84 differential protein spots under the experimental conditions (cultivars/treatments). All of these 84 protein spots were subjected to MALDI-TOF/TOF mass spectrometry to deduce their possible functions. A total of 31 proteins were identified using a combination of peptide mass fingerprinting (PMF) and MSMS fragmentation. Most of the identified proteins corresponded to enzymes belonging to photosynthesis, metabolism, transcription/translation and defense and stress categories. Results are discussed in terms of responses to pathogens.


Assuntos
Ascomicetos/fisiologia , Pisum sativum/química , Pisum sativum/microbiologia , Proteômica , Eletroforese em Gel Bidimensional , Dados de Sequência Molecular , Pisum sativum/genética , Pisum sativum/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
17.
Fam Cancer ; 9(2): 151-4, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19998059

RESUMO

Muir-Torre syndrome is a rare, inherited disease predisposing of gastrointestinal and cutaneous tumours, such as keratoacanthomas and sebaceous gland adenomas. Muir-Torre syndrome is usually inherited in an autosomal dominant fashion and associated with mutations in the mismatch repair genes, predominantly in MLH1 and MSH2 genes. This report describes a man who has multiple adenomatous colon polyps, a gastric cancer, multiple colorectal cancers and sebaceous adenomas caused by biallelic MYH germline mutations. This finding demonstrates that MYH gene analysis should be considered in Muir-Torre families where no mismatch repair gene mutations have been found. Furthermore, this report contributes to characterize the clinical phenotype caused by biallelic mutations in MYH gene, which may share with other hereditary colon cancer syndromes.


Assuntos
Reparo de Erro de Pareamento de DNA/genética , Mutação em Linhagem Germinativa/genética , Ceratoacantoma/etiologia , Síndrome de Muir-Torre/complicações , Síndrome de Muir-Torre/genética , Idoso , Alelos , Neoplasias Colorretais/genética , Reparo do DNA/genética , Humanos , Masculino , Mutação
18.
J Colloid Interface Sci ; 326(1): 103-9, 2008 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-18656205

RESUMO

Different Ag nanoparticles were prepared by four different methods (chemical reduction with trisodium citrate, chemical reduction with hydroxylamine hydrochloride, laser ablation and laser in situ photoreduction) to compare their applicability in surface-enhanced Raman scattering (SERS), their stability and other interfacial characteristics such as the pH, surface availability and the surface potential. This study was conducted by using the anthraquinone dye alizarin as a molecular probe since this molecule is able to be adsorbed onto the metal through three different forms, which relative proportions depend on the interfacial properties of the exposed metal surfaces.

19.
Spectrochim Acta A Mol Biomol Spectrosc ; 71(3): 932-45, 2008 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-18396096

RESUMO

For understanding the phenomena associated with the discoloration observed in some cases of infrared laser cleaned stonework surfaces, a comparative study of three different types and morphologies of pollution encrustation and stone substrates was undertaken. Fragments originating from monuments with historic and/or artistic value, bearing homogeneous thin soiling on Pentelic marble (Athens, Greece), thick encrustation on Hontoria limestone (Burgos, Spain) and compact thin crust on gypsum decorations (Athens, Greece), have been studied on the basis of their composition and origin, together with the conditions that may induce yellowing effects upon their laser cleaning with IR wavelengths. While irradiation in the UV (i.e. at 355 nm) could not effectively remove the encrustations studied, irradiation at 1,064 nm was found efficient to remove all the studied pollution accumulations. Discoloration towards yellow was evident in all cases and at different levels, including the samples with intentional patination layer. To the limit of Raman detection no chemical alterations were detected on the irradiated areas while the presence of yellow polar compounds in all the pollution crusts studied supports the argument that the discoloration of the stone surfaces upon their IR irradiation may be due to the uncovering of existing yellow layers as result of the migration of these compounds inwards to the original stone surface. To correct and/or prevent such undesired coloration the use of IR and UV radiation both in sequential and synchronous mode was considered, with positive results.


Assuntos
Carbonato de Cálcio/efeitos da radiação , Sulfato de Cálcio/efeitos da radiação , Materiais de Construção/efeitos da radiação , Carbonato de Cálcio/química , Sulfato de Cálcio/química , Cor , Colorimetria , Materiais de Construção/análise , Poluentes Ambientais/efeitos da radiação , Lasers , Análise Espectral Raman , Propriedades de Superfície/efeitos da radiação
20.
New Phytol ; 173(4): 703-712, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17286819

RESUMO

Parasitic weeds pose severe constraint on major agricultural crops. Varying levels of resistance have been identified and exploited in the breeding programmes of several crops. However, the level of protection achieved to date is either incomplete or ephemeral. Resistance is mainly determined by the coexistence of several mechanisms controlled by multigenic and quantitative systems. Efficient control of the parasite requires a better understanding of the interaction and their associated resistance mechanisms at the histological, genetic and molecular levels. Application of postgenomic technologies and the use of model plants should improve the understanding of the plant-parasitic plant interaction and drive not only breeding programmes through either marker-assisted selection (MAS) or transgenesis but also the development of alternative methods to control the parasite. This review presents the current approaches targeting the characterization of resistance mechanisms and explores their potentiality to control parasitic plants.


Assuntos
Fenômenos Fisiológicos Vegetais , Plantas/genética , Plantas/parasitologia , Cruzamento , Mapeamento Cromossômico , Marcadores Genéticos , Interações Hospedeiro-Parasita , Plantas Geneticamente Modificadas , Proteômica , Locos de Características Quantitativas , Transcrição Gênica
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