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1.
Anal Chem ; 85(13): 6303-11, 2013 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-23697511

RESUMO

Hyperspectral images are analytical measurements that provide spatial and structural information. The spatial description of the samples is the specific asset of these measurements and the reason why they have become so important in (bio)chemical fields, where the microdistribution of sample constituents or the morphology or spatial pattern of sample elements constitute very relevant information. Often, because of the small size of the samples, the spatial detail provided by the image acquisition systems is insufficient. This work proposes a data processing strategy to overcome this instrumental limitation and increase the natural spatial detail present in the acquired raw images. The approach works by combining the information of a set of images, slightly shifted from each other with a motion step among them lower than the pixel size of the raw images. The data treatment includes the application of multivariate curve resolution (unmixing) multiset analysis to the set of collected images to obtain the distribution maps and spectral signatures of the sample constituents. These sets of maps are noise-filtered and compound-specific representations of all the relevant information in the pixel space and decrease the dimensionality of the original image from hundreds of spectral channels to few sets of maps, one per sample constituent or element. The information in each compound-specific set of maps is combined via a super-resolution post-processing algorithm, which takes into account the shifting, decimation, and point spread function of the instrument to reconstruct a single map per sample constituent with much higher spatial detail than that of the original image measurement.


Assuntos
Tamanho Celular , Processamento de Imagem Assistida por Computador/métodos , Análise Multivariada , Células HeLa , Humanos
2.
Poult Sci ; 102(4): 102491, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36738561

RESUMO

The influence of the Ca and nutrient content of the diet fed from 16 to 19 wk of age, on egg production, egg quality, and tibiae mineralization, was studied in brown egg-laying hens from 16 to 63 wk of age. The experimental design was completely randomized with 4 prelay diets organized as a 2 × 2 factorial with 2 levels of Ca (2.5 vs. 3.8%) and 2 standardized ileal digestible Lys (g/kg) to AMEn (Mcal/kg) ratios (DLys:ME; 2.84 vs. 3.13) as main effects. From 20 to 63 wk of age, all hens received a common diet with 2.75 Mcal AMEn/kg, 0.75% DLys, and 3.8% Ca. Each treatment was replicated 18 times and the experimental unit was a cage with 10 hens. Hen production and egg quality traits were measured by period (4 wk), feeding phase (prelay and lay), and cumulatively (16-63 wk of age) and tibiae mineralization was measured at 63 wk of age. During the prelay phase, an increase in Ca delayed egg production (P = 0.065), reduced feed intake (P < 0.05), and increased BW gain (P < 0.01) and percentage of shell of the egg (P < 0.05). An increase in the DLys:ME ratio increased feed intake (P < 0.01) and reduced egg size (P < 0.01). Nutrient content of the prelay diets did not affect hen production during the lay phase, except egg weight that increased (P < 0.05) in hens previously fed the low DLys:ME ratio. Eggshell quality (weight, percentage, strength, and thickness) in this phase was better (P < 0.05) in hens previously fed 3.8% Ca. Cumulatively (16-63 wk of age), hens fed the high Ca prelay diets had better shell quality but tibiae mineralization was not affected. In conclusion, an increase in Ca content of the prelay diet from 2.5 to 3.8% improved shell quality for the entire egg cycle without showing any negative effect on hen production.


Assuntos
Cálcio , Galinhas , Animais , Feminino , Troglitazona , Óvulo , Dieta/veterinária , Cálcio da Dieta , Nutrientes , Ração Animal/análise , Oviposição , Casca de Ovo
3.
Poult Sci ; 101(9): 102044, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35926352

RESUMO

The influence of infrared beak trimming at hatch (IRBT) and the inclusion of oat hulls (OH) in the diet on growth performance, feed preference, exploratory pecking behavior, and gastrointestinal tract (GIT) development, was studied in brown-egg pullets from 0 to 15 wk of age. The experimental design was completely randomized with 4 treatments arranged as a 2 × 2 factorial with IRBT (sham vs. treated) and OH inclusion (0 vs. 3%) as main effects. Each treatment was replicated 20 times and the experimental unit was a cage with 10 pullets. Feed intake (FI), BW gain, feed conversion ratio (FCR), energy intake (EI, kcal AMEn/d), and energy conversion ratio (ECR, kcal AMEn/g of BW gain) were determined by feeding period (0 to 6, 7 to 10, and 11 to 15 wk of age) and cumulatively. Particle size preference was measured at 7 wk and exploratory pecking behavior of the pullets and at 8 to 14 wk of age. From 0 to 6 wk of age, beak trimming decreased FI (P < 0.01) and increased pullet mortality (P < 0.001) but did not affect BW gain. From 0 to 15 wk of age, OH inclusion improved BW uniformity (P = 0.090) but impaired FCR (P < 0.05) without showing any effect on BW gain or ECR. Preference for coarse particles was greater for the sham than for the treated pullets. Beak trimming and OH feeding reduced (P < 0.05) the exploratory pecking behavior of the pullets from 8 to 12 wk of age but not thereafter. Oat hulls increased the relative weights of the full gizzard and intestines at all ages (P < 0.05). In summary, beak trimming did not affect pullet performance at 15 wk of age or GIT development at any age. Oat hulls improved GIT development at all ages but did not affect BW or ECR. Both beak treatment and OH inclusion affected particle size preference and reduced the exploratory pecking behavior of the birds.


Assuntos
Bico , Galinhas , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Avena , Bico/cirurgia , Dieta/veterinária , Feminino , Trato Gastrointestinal
4.
Poult Sci ; 101(12): 102197, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36244207

RESUMO

The influence of the energy and the standardized ileal digestible lysine (DLys) content of the diet on egg production and egg quality, was studied in brown-egg laying hens from 18 to 41 wk of age. The experimental design was completely randomized with 10 treatments organized as a 2 × 5 factorial with 2 energy concentrations (2,750 and 2,800 kcal AMEn/kg) and 5 levels of DLys (values varied from 0.66 to 0.78% and 0.67 to 0.79%, for the low and high energy diets, respectively). Each treatment was replicated 10 times (10 hens per replicate). The data were analyzed using the MIXED procedure of SAS with energy concentration and DLys content of the diets as main effects. In addition, the effects of the DLys on the variables studied were partitioned into its lineal and quadratic components. From 18 to 21 wk of age (pre-peak phase), diet composition had limited effects on egg production. From 22 to 41 wk of age (peak phase), however, an increase of 50 kcal AMEn/kg diet increased egg weight (P < 0.05) and tended to improve energy intake (P = 0.083) and feed conversion ratio (P = 0.074). An increase in DLys improved linearly (P < 0.001) egg production, egg weight, egg mass, feed conversion, and energy conversion ratio, and tended to increase BW gain (P = 0.074). Diet composition did not any affect egg quality trait except shell strength that increased linearly (P < 0.05) with increases in the DLys. Cumulatively (18-41 wk of age), egg weight increased (P < 0.05) as the energy and the DLys content of the diet increased. In summary, an increase in energy and DLys content of the diet had limited effects on egg production during the prepeak phase but improved egg production, feed conversion ratio, and BW gain during the peak phase. The data indicate that hens require at least 839 mg DLys/d to maximize egg production in the peak production phase.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Lisina , Animais , Feminino , Lisina/farmacologia , Ração Animal/análise , Galinhas , Dieta/veterinária
5.
Poult Sci ; 100(7): 101211, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34111610

RESUMO

The influence of nutrient density and standardized ileal digestible lys (DLys) content of the diet on egg production and egg quality traits, was studied in brown-egg laying hens from 19 to 59 wk of age. The experimental design was completely randomized with eight treatments arranged as a 2×4 factorial with two AMEn concentrations (2,680 and 2,780 kcal/kg) and four levels of DLys (0.68, 0.72, 0.76, and 0.80%). Each treatment was replicated nine times and the experimental unit was a cage with nine hens. Hen production, egg components (proportion of albumen, yolk, and shell), egg quality traits (Haugh units, egg shell strength, and incidence of broken, dirty, and shell-less eggs) were measured by period (28 d) and cumulatively. Data were analyzed as a completely randomized design with energy concentration, level of DLys, and their interactions as main effects. In addition, the effects of the level of DLys on the variables studied, were partitioned into its linear and quadratic components. No interactions between AMEn and DLys content of the diet were detected for any of the traits studied and therefore, only main effects are presented. An increase in the AMEn concentration of the diet from 2,680 to 2,780 kcal/kg increased energy intake (P < 0.05) and egg weight (P < 0.001) and improved feed conversion ratio (P < 0.05). An Increase in DLys from 0.68 to 0.80% did not affect the number of eggs produced but increased linearly egg weight (P < 0.01) and egg mass production (P < 0.05). Diet did not affect egg quality. In conclusion, an increase in the AMEn content of the diet from 2,680 to 2,780 kcal/kg increased egg weight and improved feed efficiency. Laying hens require no more than 744 mg DLys/d (corresponding to 0.68% DLys) to optimize egg production. However, when the objective is to maximize egg weight, hens should consume at least 843 mg DLys/d (corresponding to 0.76% D Lys).


Assuntos
Galinhas , Lisina , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta , Ovos , Feminino , Óvulo
6.
Ann Oncol ; 21(7): 1552-1557, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20231303

RESUMO

BACKGROUND: To assess whether deletions involving codons 557 and/or 558 (critical deletions) of exon 11 of KIT are relevant in the prognosis of relapse-free survival (RFS) in gastrointestinal stromal tumor (GIST) patients with a long follow-up. PATIENTS AND METHODS: A univariate and multivariate analysis for RFS were carried out on 162 localized GIST patients over the entire follow-up period and over the intervals 0-4 years and >4 years. Factors assessed among others were Fletcher/National Institutes of Health and Miettinen-Lasota/Armed Forces Institute of Pathology (M-L/AFIP) risk categories, critical deletions and non-deletion-type mutation (NDTM) within exon 11 of KIT. RESULTS: Multivariate analyses revealed that M-L/AFIP [relative risk (RR) 11.45, confidence interval (CI) 4.40-29.76, for the high-risk subgroup and RR 5.97, CI 2.09-17.06, for the intermediate subgroup] and critical deletions (RR 3.05, CI 1.59-5.85) were independent prognostic factors for RFS for the first 4 years and for the entire follow-up period. Beyond 4 years, the high-risk M-L/AFIP subgroup (RR 8.12, CI 1.48-44.4) and NDTM (RR 6.42, CI 1.17-35.12) were independent prognostic factors for RFS. The median follow-up was 84 months. CONCLUSION: Critical deletions represent a time-dependent prognostic factor limited to the first 4 years after surgery, which could help identify a subset with higher and earlier risk for relapse in GIST patients.


Assuntos
Códon/genética , Tumores do Estroma Gastrointestinal/genética , Recidiva Local de Neoplasia/genética , Proteínas Proto-Oncogênicas c-kit/genética , Deleção de Sequência/genética , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Seguimentos , Tumores do Estroma Gastrointestinal/mortalidade , Tumores do Estroma Gastrointestinal/patologia , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
7.
Poult Sci ; 99(2): 1010-1018, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32036958

RESUMO

We studied the effects of restricting the access to feed on the anticipatory eating behavior, growth performance, and the development of the proximal part of the gastrointestinal tract (GIT) in broilers. The experiment consisted in physical restriction of the access of broilers to feed for 0, 4, 6, or 8 h per day from 7 to 19 D of age. At 10, 13, 16, and 19 D of age, immediately before the start of the feed restriction (FR) period, 2 birds per cage were euthanized to evaluate crop and gizzard development. The experimental design was completely randomized, and the linear (L) and quadratic (Q) effects of fasting length on growth performance and GIT traits were determined. In addition, the effect of broiler age on GIT development was studied. From 7 to 19 D of age, ADFI (L, Q; P ≤ 0.05) and BW gain (L; P ≤ 0.01) decreased as the length of the FR period increased, with most of the differences observed with 6 or more hours of fasting. However, feed conversion ratio was not affected by FR length. The relative weight of the crop (% BW) and its fresh content increased (L; P ≤ 0.001) and the moisture of the digesta (%) decreased (L; P ≤ 0.001) as the FR period increased. The DM content (g) of the crop increased with FR, with most of the differences observed with 6 or more hours of fasting (L, Q; P ≤ 0.001). At 19 D of age, the Lactobacillus spp. count in the crop increased (L; P ≤ 0.05) with increase in the FR period. Fasting did not affect any gizzard trait at any age. In summary, physical restriction of the access to feed for 6 h or more reduced BW gain but did not affect feed conversion ratio in broilers from 7 to 19 D of age. Feed restriction for 4 to 8 h stimulated the anticipatory feeding behavior and crop development in broilers.


Assuntos
Galinhas/fisiologia , Papo das Aves/crescimento & desenvolvimento , Comportamento Alimentar , Privação de Alimentos , Moela das Aves/crescimento & desenvolvimento , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Distribuição Aleatória , Fatores de Tempo
8.
Talanta ; 208: 120455, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31816732

RESUMO

Intratumour heterogeneity due to cancer cell clonal evolution and microenvironment composition and tumor differences due to genetic variations between patients suffering of the same cancer pathology play a crucial role in patient response to therapies. This study is oriented to show that matrix-assisted laser-desorption ionization-Mass spectrometry imaging (MALDI-MSI), combined with an advanced multivariate data processing pipeline can be used to discriminate subtle variations between highly similar colorectal tumors. To this aim, experimental tumors reproducing the emergence of drug-resistant clones were generated in athymic mice using subcutaneous injection of different mixes of two isogenic cell lines, the irinotecan-resistant HCT116-SN50 (R) and its sibling human colon adenocarcinoma sensitive cell line HCT116 (S). Because irinotecan-resistant and irinotecan-sensitive are derived from the same original parental HCT116 cell line, their genetic characteristics and molecular compositions are closely related. The multivariate data processing pipeline proposed relies on three steps: (a) multiset multivariate curve resolution (MCR) to separate biological contributions from background; (b) multiset K-means segmentation using MCR scores of the biological contributions to separate between tumor and necrotic parts of the tissues; and (c) partial-least squares discriminant analysis (PLS-DA) applied to tumor pixel spectra to discriminate between R and S tumor populations. High levels of correct classification rates (0.85), sensitivity (0.92) and specificity (0.77) for the PLS-DA classification model were obtained. If previously labelled tissue is available, the multistep modeling strategy proposed constitutes a good approach for the identification and characterization of highly similar phenotypic tumor subpopulations that could be potentially applicable to any kind of cancer tissue that exhibits substantial heterogeneity.


Assuntos
Neoplasias Colorretais/classificação , Animais , Linhagem Celular Tumoral , Análise Discriminante , Humanos , Análise dos Mínimos Quadrados , Camundongos Nus , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
9.
Clin Transl Oncol ; 22(2): 270-278, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31981078

RESUMO

Cervical cancer (CC) is the fourth most common cancer in women worldwide, strongly linked to high-risk human papilloma virus infection. In high-income countries, the screening programs have dramatically decreased the incidence of CC; however, the lack of accessibility to them in developing countries makes CC an important cause of mortality. Clinical stage is the most relevant prognostic factor in CC. The new FIGO staging system published in 2018 is more accurate than the previous one since it takes into account the lymph node status. In early stages, the primary treatment is surgery-with some concerns recently raised regarding minimally invasive surgery because it might decrease survival-or radiotherapy, whereas concomitant chemo-radiotherapy is the conventional approach in locally advanced stages. For recurrent or metastatic CC, the combination of chemotherapy plus bevacizumab is the preferred therapy. Immunotherapy approach based on checkpoint inhibitors is evolving as the election therapy following failure to platinum therapy.


Assuntos
Ensaios Clínicos como Assunto/normas , Guias de Prática Clínica como Assunto/normas , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/terapia , Feminino , Humanos , Oncologia , Sociedades Médicas
10.
Anal Chim Acta ; 1074: 69-79, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31159941

RESUMO

The characterization of cancer tissues by matrix-assisted laser desorption ionization-mass spectrometry images (MALDI-MSI) is of great interest because of the power of MALDI-MS to understand the composition of biological samples and the imaging side that allows for setting spatial boundaries among tissues of different nature based on their compositional differences. In tissue-based cancer research, information on the spatial location of necrotic/tumoral cell populations can be approximately known from grayscale images of the scanned tissue slices. This study proposes as a major novelty the introduction of this physiologically-based information to help in the performance of unmixing methods, oriented to extract the MS signatures and distribution maps of the different tissues present in biological samples. Specifically, the information gathered from grayscale images will be used as a local rank constraint in Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS) for the analysis of MALDI-MSI of cancer tissues. The use of this constraint, setting absence of certain kind of tissues only in clear zones of the image, will help to improve the performance of MCR-ALS and to provide a more reliable definition of the chemical MS fingerprint and location of the tissues of interest. The general strategy to address the analysis of MALDI-MSI of cancer tissues will involve the study of the MCR-ALS results and the posterior use of MCR-ALS scores as dimensionality reduction for image segmentation based on K-means clustering. The resolution method will provide the MS signatures and their distribution maps for each tissue in the sample. Then, the resolved distribution maps for each biological component (MCR scores) will be submitted as initial information to K-means clustering for image segmentation to obtain information on the boundaries of the different tissular regions in the samples studied. MCR-ALS prior to K-means not only provides the desired dimensionality reduction, but additionally resolved non-biological signal contributions are not used and the weight given to the different biological components in the segmentation process can be modulated by suitable preprocessing methods.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Neoplasias/patologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Algoritmos , Animais , Análise por Conglomerados , Cor , Feminino , Células HCT116 , Xenoenxertos/patologia , Humanos , Análise dos Mínimos Quadrados , Camundongos Nus , Análise Multivariada , Análise de Regressão , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/estatística & dados numéricos
11.
Clin Transl Oncol ; 20(1): 38-46, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29149431

RESUMO

Gestational trophoblastic disease (GTD) is a rare but curable disease. Recent improvements in diagnosis and molecular biology have resulted in changes in staging and treatment. These guidelines provide evidence-based recommendation on how to manage GTD.


Assuntos
Doença Trofoblástica Gestacional/diagnóstico , Doença Trofoblástica Gestacional/patologia , Doença Trofoblástica Gestacional/terapia , Feminino , Humanos , Gravidez
12.
Histol Histopathol ; 32(12): 1351-1358, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28585678

RESUMO

The endocannabinoids are cannabinoids synthesized by mammalian tissues. These compounds are closely related to the regulation of the male reproductive system. However, little is known about the effects produced by 2-arachidonoylglycerol (2AG) on in vitro human sperm functions. This study was undertaken to determine the effects produced by 2AG on fresh human sperm and in the capacitation technique. Semen samples from healthy young men were exposed to different concentrations of 2AG before and during capacitation technique. In this work, we have demonstrated that 2AG induces the spontaneous acrosome reaction and reduces progressive motility in fresh human sperm. During the capacitation technique, sperm becomes more sensitive to low concentrations of 2AG, triggering the acrosome reaction and inhibiting protein phosphorylation. In summary, 2AG affects the in vitro functionality of human sperm by reducing motility, inhibiting capacitation and triggering the acrosome reaction.


Assuntos
Reação Acrossômica/efeitos dos fármacos , Ácidos Araquidônicos/toxicidade , Endocanabinoides/toxicidade , Glicerídeos/toxicidade , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Adolescente , Adulto , Humanos , Masculino , Adulto Jovem
13.
Anal Chim Acta ; 881: 24-36, 2015 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-26041517

RESUMO

Hyperspectral images can provide useful biochemical information about tissue samples. Often, Fourier transform infrared (FTIR) images have been used to distinguish different tissue elements and changes caused by pathological causes. The spectral variation between tissue types and pathological states is very small and multivariate analysis methods are required to describe adequately these subtle changes. In this work, a strategy combining multivariate curve resolution-alternating least squares (MCR-ALS), a resolution (unmixing) method, which recovers distribution maps and pure spectra of image constituents, and K-means clustering, a segmentation method, which identifies groups of similar pixels in an image, is used to provide efficient information on tissue samples. First, multiset MCR-ALS analysis is performed on the set of images related to a particular pathology status to provide basic spectral signatures and distribution maps of the biological contributions needed to describe the tissues. Later on, multiset segmentation analysis is applied to the obtained MCR scores (concentration profiles), used as compressed initial information for segmentation purposes. The multiset idea is transferred to perform image segmentation of different tissue samples. Doing so, a difference can be made between clusters associated with relevant biological parts common to all images, linked to general trends of the type of samples analyzed, and sample-specific clusters, that reflect the natural biological sample-to-sample variability. The last step consists of performing separate multiset MCR-ALS analyses on the pixels of each of the relevant segmentation clusters for the pathology studied to obtain a finer description of the related tissue parts. The potential of the strategy combining multiset resolution on complete images, multiset segmentation and multiset local resolution analysis will be shown on a study focused on FTIR images of tissue sections recorded on inflamed and non-inflamed palatine tonsils.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Tonsila Palatina/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Tonsilite/diagnóstico , Análise por Conglomerados , Humanos , Análise dos Mínimos Quadrados , Análise Multivariada
14.
Clin Transl Oncol ; 17(12): 1036-42, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26650487

RESUMO

Cervical cancer (CC) is the second most common cancer worldwide, strongly linked to high-risk human papilloma virus infection. Although screening programs have led to a relevant reduction in the incidence and mortality due to CC in developed countries, it is still an important cause of mortality in undeveloped countries. Clinical stage is still the most relevant prognostic factor. In early stages, the primary treatment is surgery or radiotherapy, whereas concomitant chemo-radiotherapy is the conventional approach in locally advanced stages. In the setting of recurrent or metastatic CC, for the first time ever, the combination of chemotherapy plus bevacizumab prolongs the overall survival beyond 12 months. Therefore, this regimen is considered by most of the oncologist a new standard of care for metastatic/recurrent CC.


Assuntos
Guias de Prática Clínica como Assunto/normas , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/terapia , Ensaios Clínicos como Assunto , Terapia Combinada , Gerenciamento Clínico , Detecção Precoce de Câncer , Feminino , Humanos , Oncologia , Estadiamento de Neoplasias , Prognóstico , Sociedades Médicas
15.
Anal Chem ; 72(9): 1956-63, 2000 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-10815951

RESUMO

The solvatochromic comparison method has been used to probe the interactions of solutes with binary solvent mixtures of methanol-water and acetonitrile-water. The solute spectra recorded in these mixtures are composed of the additive spectral contributions of the different solvated species of the solute, i.e., the water-solvated species, the cosolvent-solvated species, and the species solvated by water-solvent complexes. Multivariate curve resolution-alternating least squares has been used to model the solvation of the solutes as a function of the composition of the binary solvent mixture. Spectra and concentration profiles of the dye surrounded by the different solvation environments have been isolated. For the first time, solute spectra solvated exclusively by methanol-water and acetonitrile-water complexes have been obtained, and the solvatochromic parameters of dipolarity/polarizability and hydrogen-bonding acidity have been estimated for these complex species.

16.
J Inorg Biochem ; 63(3): 155-73, 1996 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-8758880

RESUMO

The solvent effect on the acid-base and complexation behavior of the homopolynucleotide polyuridylic acid (poly(U)) has been studied by means of potentiometric and spectrometric titrations (circular dichroism and UV-VIS) in water and in 30 and 50% (v/v) dioxane-water media. The potentiometric studies revealed the absence of polyelectrolytic effects in the acid-base equilibrium, and the spectrometric experiments detected only a random coil conformation associated with both the protonated and deprotonated species. The common behavior observed in the three media seems to indicate the weakness of both intramolecular interactions, i.e., base stacking, and solute/solvent interactions, i.e., hydrogen-bonding, and consequently their small effect during the protonation process. Differences regarding the solubility of the deprotonated species in the solvents used are due to the difficult stabilization of such a charged species in the low polar environment of the dioxane-water mixtures. Complexation has been exhaustively studied in aqueous media, and no conformational changes have been noticed in the only copper(II)-poly(U) complex detected. The inclusion of the copper(II) ion in the macromolecular skeleton of the polynucleotide does not contribute to an ordination of the structure, which remains as a random coil. No comparison between this equilibrium in aqueous solution and in the hydroorganic mixtures could be carried out since the limited pH range of the soluble complex in those solvent mixtures prevented a rigorous quantitative monitoring of such a chemical process.


Assuntos
Cobre/metabolismo , Poli U/química , Solventes , Ácidos/química , Sequência de Bases , Dicroísmo Circular , Cobre/química , Dioxanos , Análise dos Mínimos Quadrados , Dados de Sequência Molecular , Nucleotídeos Cíclicos/química , Poli U/metabolismo , Potenciometria , Prótons , Espectrofotometria/métodos , Titulometria , Raios Ultravioleta , Água
17.
Burns ; 26(5): 498-500, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10812277

RESUMO

A patient was presented with significant burns resulting from a workplace accident in a zinc production unit. This occurred as a result of the spontaneous combustion of zinc bleed under high pressure. The patient sustained burns to the face, body, and hands and suffered significant injury to the left cornea. Computed imaging revealed solid particles in the ethmoid sinus and also in the right nasal fossa, dissecting the right lacrimal duct. Photographic documentation is presented. This injury was potentially preventable and resulted from poor observance of safety procedures.


Assuntos
Acidentes de Trabalho , Queimaduras Químicas/etiologia , Indústria Química , Zinco/efeitos adversos , Queimaduras Oculares/etiologia , Traumatismos Faciais/etiologia , Corpos Estranhos/diagnóstico por imagem , Corpos Estranhos/etiologia , Traumatismos da Mão/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Cavidade Nasal/diagnóstico por imagem , Pressão , Combustão Espontânea , Tomografia Computadorizada por Raios X
18.
Rev Esp Enferm Dig ; 96(6): 415-7; 418-9, 2004 Jun.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-15230671

RESUMO

Metastatic tumors to the breast from colon adenocarcinoma are very rare. They are usually indicative of disseminated disease, and the prognosis is poor. Generally, radical operation should be avoided unless needed for palliation. This case report described a patient with breast metastasis from colon adenocarcinoma treated by simple mastectomy.


Assuntos
Adenocarcinoma/secundário , Neoplasias da Mama/secundário , Neoplasias do Colo/patologia , Adenocarcinoma/diagnóstico por imagem , Adulto , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Mamografia
19.
Anal Chim Acta ; 819: 15-25, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24636406

RESUMO

Polymorphism is often encountered in many crystalline compounds. To control the quality of the products, it is relevant knowing the potential presence of polymorph transformations induced by different agents, such as light exposure or temperature changes. Raman images offer a great potential to identify polymorphs involved in a process and to accurately describe this kind of solid-state transformation in the surface scanned. As a way of example, this work proposes the use of multiset analysis on the series of Raman hyperspectral images acquired during a thermal induced transformation of carbamazepine as the optimal way to extract useful information about polymorphic or any other kind of dynamic transformation among process compounds. Image multiset analysis, performed by using Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS), will furnish pure spectra and distribution maps of the compounds involved in the process and, hence, will allow the identification of polymorphs and, more important, the description of the process evolution at a global and local (pixel) level. Thus, process will be defined from a spatial point of view and by means of a set of global process profiles dependent on the process control variable. The results obtained confirm the power of this methodology and show the crucial role of the spatial information contained in the image (absent in conventional spectroscopy) for a correct process description.

20.
Clin Transl Oncol ; 16(4): 351-61, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24085574

RESUMO

The increase in life expectancy in the western world means that we are faced with patients diagnosed with breast cancer in old age with increasing frequency. The management of these cases is a challenge for the oncologist, who must take into account the conditions associated with advanced age and the lack of trials in this population. In this review, we addressed the incorporation of geriatric assessment methods that may be useful in making decisions, the particular biological characteristics of breast cancer in elderly patients and their treatment in both localized and advanced disease. Finally, we collected recommendations based on scientific evidence regarding the monitoring and life-style after finishing treatment.


Assuntos
Neoplasias da Mama/terapia , Avaliação Geriátrica/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos
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