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1.
Breast ; 70: 49-55, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37331094

RESUMO

PURPOSE: To provide more insight into late treatment-related toxicities among breast cancer (BC) survivors by comparing morbidities and risk factors between BC survivors and age-matched controls. MATERIALS AND METHODS: All female participants diagnosed with BC before inclusion in Lifelines, a population-based cohort in the Netherlands, were selected and matched 1:4 to female controls without any oncological history on birth year. Baseline was defined as the age at BC diagnosis. Outcomes were obtained from questionnaires and functional analyses performed at entry to Lifelines (follow-up 1; FU1) and several years later (FU2). Cardiovascular and pulmonary events were defined as morbidities that were absent at baseline but present at FU1 or FU2. RESULTS: The study consisted of 1,325 BC survivors and 5,300 controls. The median period from baseline (i.e., BC treatment) to FU1 and FU2 was 7 and 10 years, respectively. Among BC survivors more events of heart failure (OR: 1.72 [1.10-2.68]) and less events of hypertension (OR: 0.79 [0.66-0.94]) were observed. At FU2, more electrocardiographic abnormalities were found among BC survivors compared to controls (4.1% vs. 2.7%, respectively; p = 0.027) and Framingham scores for the 10-year risk of coronary heart disease were lower (difference: 0.37%; 95% CI [-0.70 to -0.03%]). At FU2, BC survivors had more frequently a forced vital capacity below the lower limit of normal than controls (5.4% vs. 2.9%, respectively; p = 0.040). CONCLUSION: BC survivors are at risk of late treatment-related toxicities despite a more favourable cardiovascular risk profile compared to age-matched female controls.


Assuntos
Neoplasias da Mama , Sobreviventes de Câncer , Feminino , Humanos , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/terapia , Grupos Controle , Estudos Prospectivos , Fatores de Risco , Sobreviventes , Morbidade
2.
Phys Med Biol ; 63(4): 045026, 2018 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-29182154

RESUMO

A prerequisite for adaptive dose-tracking in radiotherapy is the assessment of the deformable image registration (DIR) quality. In this work, various metrics that quantify DIR uncertainties are investigated using realistic deformation fields of 26 head and neck and 12 lung cancer patients. Metrics related to the physiologically feasibility (the Jacobian determinant, harmonic energy (HE), and octahedral shear strain (OSS)) and numerically robustness of the deformation (the inverse consistency error (ICE), transitivity error (TE), and distance discordance metric (DDM)) were investigated. The deformable registrations were performed using a B-spline transformation model. The DIR error metrics were log-transformed and correlated (Pearson) against the log-transformed ground-truth error on a voxel level. Correlations of r ⩾ 0.5 were found for the DDM and HE. Given a DIR tolerance threshold of 2.0 mm and a negative predictive value of 0.90, the DDM and HE thresholds were 0.49 mm and 0.014, respectively. In conclusion, the log-transformed DDM and HE can be used to identify voxels at risk for large DIR errors with a large negative predictive value. The HE and/or DDM can therefore be used to perform automated quality assurance of each CT-based DIR for head and neck and lung cancer patients.


Assuntos
Algoritmos , Neoplasias de Cabeça e Pescoço/patologia , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Pulmonares/patologia , Reconhecimento Automatizado de Padrão/métodos , Tomografia Computadorizada por Raios X/métodos , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Incerteza
3.
Biochemistry ; 36(43): 13241-7, 1997 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-9341213

RESUMO

The structure of double-helical poly(dG-dC).poly(dG-dC) is investigated at various pH values with Raman spectroscopy, absorption spectroscopy, and circular dichroism. A comparison is made between the B-form with Watson-Crick base pairing at 1 mM [Na+] and pH 7.2, the Z-form with Watson-Crick base pairing at 4 M [Na+] and pH 7.2, and a different structure at 1 mM [Na+] and pH 4.5 as well as at 150 mM [Na+] and pH 3.1. The CD spectrum of poly(dG-dC). poly(dG-dC) under the latter conditions does not show a negative band at 290 nm. The structure is a double-helical structure different from the B-form and the Z-form according to circular dichroism, Raman, and absorption spectroscopic studies. The Raman spectra evidence that the structure contains Hoogsteen base pairing. This can be accommodated in the double helix when the cytosine group is protonated and the sugar-guanine conformer has adopted a C2'-endo/syn conformation. It is shown that this antiparallel-stranded Hoogsteen base paired structure can be maintained under varying conditions, balancing the decrease in pH with an increased salt concentration. It is further concluded that the proton-induced transition from a Watson-Crick to a Hoogsteen base pair is aided by a decrease of [Na+] at pH 4.5 and occurs prior to a conversion from a right-handed helix to a left-handed helix.


Assuntos
Conformação de Ácido Nucleico , Polidesoxirribonucleotídeos/química , Composição de Bases , Dicroísmo Circular , Citidina , Guanina , Guanosina , Concentração de Íons de Hidrogênio , Prótons , Cloreto de Sódio , Espectrofotometria , Análise Espectral Raman
4.
Eur Biophys J ; 27(6): 582-9, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9791941

RESUMO

Confocal Raman micro-spectroscopy has been applied to investigate the activation process of single, living neutrophilic granulocytes. Both resting cells as well as activated cells were measured. The activation of cells was performed with phorbol-12-myristate-13-acetate activator and Escherichia Coli bacteria. Raman microspectroscopy combines a high spatial resolution inside a single, living cell with detailed material information. Using this approach it can be concluded that activation of the cells with phorbol-12-myristate-13-acetate causes a change in the redox state of cytochrome b558. This protein is a part of the NADPH-oxidase complex that neutrophilic granulocytes employ to generate O-2, superoxide anion. Additionally a change in the redox state of myeloperoxidase can be observed. Myeloperoxidase is known to react with O-2. Activation of the cells with bacteria gives rise to corresponding changes in the Raman spectra. From this single cell study it can be concluded that the enzymes cytochrome b558 and myeloperoxidase are present inside the cytoplasm of the living cell, while participating in the redox processes. Activation causes an intra-cellular release of oxygen metabolites. Activation with bacteria of neutrophilic granulocytes from a patient with chronic granulomatous disease, that contain no cytochrome b558, led to typical changes in the redox state of myeloperoxidase. This indicates that in the bacterium/neutrophilic granulocyte system oxygen metabolites are generated that are capable of reacting with MPO.


Assuntos
Ativação de Macrófagos/fisiologia , Neutrófilos/fisiologia , Doença Granulomatosa Crônica/patologia , Humanos , Técnicas In Vitro , Microscopia Confocal , NADPH Oxidases/metabolismo , Neutrófilos/ultraestrutura , Peroxidase/deficiência , Análise Espectral Raman , Acetato de Tetradecanoilforbol/farmacologia
5.
Opt Lett ; 26(1): 36-8, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-18033499

RESUMO

A scheme for molecular tagging velocimetry is presented that can be used in air flows without any kind of seeding. The method is based on the local and instantaneous creation of nitric oxide (NO) molecules from N(2) and O(2) in the waist region of a focused ArF excimer laser beam. This NO distribution is advected by the flow and can be visualized any time later by laser-induced fluorescence in the gamma bands. The creation of NO is confirmed by use of an excitation spectrum. Two examples of the application of the new scheme for air-flow velocimetry are given in which single laser pulses are used for creation and visualization of NO.

6.
Biophys J ; 74(6): 3250-5, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9635778

RESUMO

With (resonance) Raman microscospectroscopy, it is possible to investigate the chemical constitution of a very small volume (0.5 fl) in a living cell. We have measured resonance Raman spectra in the cytoplasm of living normal, myeloperoxidase (MPO)-deficient, and cytochrome b558-deficient neutrophils and in isolated specific and azurophilic granule fractions, using an excitation wavelength of 413.1 nm. Similar experiments were performed after reduction of the redox centers by the addition of sodium dithionite. The specific and azurophilic granules in both redox states appeared to have clearly distinguishable Raman spectra when exciting at a wavelength of 413.1 nm. The azurophilic granules and the cytochrome b558-deficient neutrophils showed Raman spectra similar to that of the isolated MPO. The spectra of the specific granules and the MPO-deficient neutrophils corresponded very well to published cytochrome b558 spectra. The resonance Raman spectrum of the cytoplasmic region of normal neutrophilic granulocytes could be fitted with a combination of the spectra of the specific and azurophilic granules, which shows that the Raman signal of neutrophilic granulocytes mainly originates from MPO and cytochrome b558, at an excitation wavelength of 413.1 nm.


Assuntos
Grupo dos Citocromos b/sangue , NADPH Oxidases , Neutrófilos/metabolismo , Peroxidase/sangue , Grupo dos Citocromos b/deficiência , Grânulos Citoplasmáticos/metabolismo , Humanos , Técnicas In Vitro , Microquímica , Peroxidase/deficiência , Sensibilidade e Especificidade , Análise Espectral Raman/instrumentação , Análise Espectral Raman/métodos
7.
Opt Lett ; 24(10): 664-6, 1999 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-18073816

RESUMO

Raman imaging is shown to be a very suitable technique for simultaneous density mapping of different species in dry air and N(2) supersonic nozzle flows. The salient features of Raman scattering are its molecular sensitivity and the fact that it can be spectrally separated from strong reflections and Mie scattering. We collected Raman images of both N(2) and O(2) concurrently by imaging the flow through an imaging spectrograph with a broad entrance slit onto a CCD camera. The main advantage of this method is that different species can be imaged under exactly the same flow conditions.

8.
Eur J Biochem ; 264(1): 211-7, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10447690

RESUMO

The heme group of all mammalian peroxidases is covalently linked to the protein matrix via two esterbonds, as we have recently shown by Fourier transform infrared (FTIR) difference spectroscopy [Kooter, I. M., Pierik, A.J., Merkx, M., Averill, B.A., Moguilevsky, N., Bollen, A. & Wever, R. (1997) J. Am. Chem. Soc. 119, 11542-11543]. We have examined the effects of mutation of Asp94 and Glu242, responsible for those ester bonds in myeloperoxidase, on the spectroscopic properties and catalytic activity of this enzyme. Mutation of Asp94 in myeloperoxidase results in two species. The first species has spectroscopic characteristics similar to that of wild-type myeloperoxidase. The second species has spectroscopic characteristics similar to that of Met243-->Gln mutant, and it is therefore concluded that, besides loss of the ester bond involving Asp94, this species also has lost the sulfonium ion linkage that is also characteristic of myeloperoxidase. The Asp94-->Asn mutant still has about 30% residual peroxidase activity while for the Asp94-->Val mutant only a few percentage activity is left. When Glu242 is mutated the sulfonium ion linkage is not affected, but this residue together with its neighbouring residue Met243, according to resonance Raman spectra, is responsible for the low symmetry of the heme group. Mutation of either of these residues results in loss of the bowed distortion from the planar conformation, and in a heme group with higher symmetry. For the Glu242-->Gln mutant 8% residual peroxidase activity is found.


Assuntos
Ácido Aspártico/química , Ácido Glutâmico/química , Heme/química , Peroxidase/metabolismo , Ésteres , Cinética , Mutagênese Sítio-Dirigida , Peroxidase/química , Peroxidase/genética , Análise Espectral Raman
9.
Biophys J ; 78(5): 2606-13, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10777757

RESUMO

We have obtained new evidence for the occurrence of intracellular NADPH-oxidase activity in neutrophilic and eosinophilic granulocytes upon stimulation with phorbol myristate acetate (PMA). PMA activation leads to a partial translocation of cytochrome b(558) from the membranes of the specific granules to the plasma membrane. It was suggested that NADPH-oxidase activity only takes place in the plasma membrane, leading to an extracellular release of oxygen metabolites because cellular self-destruction can be avoided in this way. The effects of PMA activation were indirectly studied in recent experiments employing scavengers of extracellular superoxide anion and hydrogen peroxide, and support for intracellular NADPH-oxidase activity was obtained. In this paper we use Raman microspectroscopy as a direct method to study intracellular molecular reactions that result from cellular triggering by PMA. The molecular specificity of this microscopic method enables us to show that intracellular reduction of both myeloperoxidase (MPO) and cytochrome b(558) occurs in neutrophilic granulocytes. Control measurements with cytochrome b(558)-deficient neutrophilic granulocytes did not show a reduction of intracellular MPO. This is direct support for the occurrence of intracellular NADPH-oxidase activity in organelles that must be in close contact with the azurophilic granules that contain MPO. Furthermore, a comparison was made with chemical reactions occurring in eosinophilic granulocytes after activation with PMA. Moreover, in these cells an intracellular reduction of eosinophil peroxidase was observed.


Assuntos
Granulócitos/metabolismo , Fenômenos Biofísicos , Biofísica , Grupo dos Citocromos b/metabolismo , Granulócitos/efeitos dos fármacos , Humanos , Técnicas In Vitro , Líquido Intracelular/metabolismo , NADPH Oxidases/metabolismo , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Oxirredução , Peroxidase/metabolismo , Análise Espectral Raman , Acetato de Tetradecanoilforbol/farmacologia
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