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1.
Phys Rev Lett ; 127(7): 077202, 2021 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-34459640

RESUMEN

We investigate the role of domain walls in the ultrafast magnon dynamics of an antiferromagnetic NiO single crystal in a pump-probe experiment with variable pump photon energy. Analyzing the amplitude of the energy-dependent photoinduced ultrafast spin dynamics, we detect a yet unreported coupling between the material's characteristic terahertz- and gigahertz-magnon modes. We explain this unexpected coupling between two orthogonal eigenstates of the corresponding Hamiltonian by modeling the magnetoelastic interaction between spins in different domains. We find that such interaction, in the nonlinear regime, couples the two different magnon modes via the domain walls and it can be optically exploited via the exciton-magnon resonance.

2.
Water Sci Technol ; 70(9): 1503-9, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25401314

RESUMEN

A study has been conducted on a retention soil filter (RSF) to test its effectiveness in removing pharmaceutical residues and microorganisms from combined sewer overflows (CSOs). Efficient removal of solids, nutrients and heavy metals has already been proven. The possibility that organic micropollutants and microorganisms are also retained by the use of RSFs has been identified, but data are lacking. Results obtained in this study, in which testing for removal by a RSF of numerous micro-pollutant substances was performed, are most promising. The pharmaceuticals diclofenac and ibuprofen are presented in detail as examples of such micropollutants. Both showed a reduction in positive samples of more than 55% as well as a significant reduction in median and maximum concentrations. For microorganisms such as Escherichia coli, coliphages and Giardia lamblia (cysts), an average reduction in concentrations by three logarithmic steps (99.9%) was achieved. These results add to the evidence that using a RSF in the advanced treatment of wastewater from CSOs reduces the exposure of water-courses to pharmaceutical residues and microbial contamination.


Asunto(s)
Filtración , Preparaciones Farmacéuticas/análisis , Microbiología del Suelo , Suelo/parasitología , Eliminación de Residuos Líquidos , Aguas Residuales , Contaminantes Químicos del Agua/análisis , Colifagos/aislamiento & purificación , Escherichia coli/aislamiento & purificación , Alemania , Giardia lamblia/aislamiento & purificación , Aguas Residuales/análisis , Aguas Residuales/microbiología , Aguas Residuales/parasitología
3.
Nat Genet ; 15 Spec No: 417-74, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9140409

RESUMEN

Cytogenetic studies over the past few decades have revealed clonal chromosomal aberrations in almost 27,000 human neoplasms. Many of these neoplasia-associated chromosomal abnormalities have been characterised at the molecular level, revealing previously unknown genes that are closely associated with the tumorigenic process. Information on chromosome changes in neoplasia is growing rapidly, making it difficult to identify all recurrent chromosomal aberrations. We have developed a computer program to ascertain, for the first time, all recurrent structural abnormalities in all haematological malignancies and solid tumours published up to June 1996. Out of 26,523 cases, a total of 215 balanced and 1,588 unbalanced recurrent aberrations were identified among 75 different neoplastic disorders. Our compilation of all recurrent balanced and unbalanced neoplasia-associated rearrangements should help in directing future efforts aimed at identifying the molecular mechanisms involved in tumorigenesis.


Asunto(s)
Aberraciones Cromosómicas , Mapeo Cromosómico , Cromosomas Humanos , Bases de Datos Factuales , Neoplasias/genética , Reordenamiento Génico , Humanos , Cariotipificación , Neoplasias/epidemiología , Translocación Genética
4.
Sci Adv ; 7(11)2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33692110

RESUMEN

Nations' food consumption patterns are increasingly globalized and trade dependent. Natural resources used for agriculture (e.g., water, pollinators) are hence being virtually exchanged across countries. Inspired by the virtual water concept, we, herein, propose the concept of virtual biotic pollination flow as an indicator of countries' mutual dependence on biodiversity-based ecosystem services and provide an online tool to visualize trade flow. Using information on 55 pollinator-dependent crop markets (2001-2015), we show that countries with higher development level demand high levels of biodiversity-based services to sustain their consumption patterns. Such patterns are supported by importation of virtual biotic pollination (up to 40% of national imports of pollinator-dependent crops) from developing countries, stimulating cropland expansion. Quantifying virtual pollination flow can help develop new global socioeconomic policies to meet the interconnected challenges of biodiversity loss, ecosystem health, and social justice.

5.
Antimicrob Agents Chemother ; 54(1): 312-9, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19822705

RESUMEN

Chip calorimetry is introduced as a new monitoring tool that provides real-time information about the physiological state of biofilms. Its potential for use for the study of the effects of antibiotics and other biocides was tested. Established Pseudomonas putida biofilms were exposed to substances known to cause toxicity by different mechanisms and to provoke different responses of defense and resistance. The effects of these compounds on heat production rates were monitored and compared with the effects of these compounds on the numbers of CFU and intracellular ATP contents. The real-time monitoring potential of chip calorimetry was successfully demonstrated by using as examples the fast-acting poisons formaldehyde and 2,4-dinitrophenol (DNP). A dosage of antibiotics initially increased the heat production rate. This was discussed as being the effect of energy-dependent resistance mechanisms (e.g., export and/or transformation of the antibiotic). The subsequent reduction in the heat production rate was attributed to the loss of activity and the death of the biofilm bacteria. The shapes of the death curves were in agreement with the assumed variation in the levels of exposure of cells within the multilayer biofilms. The new monitoring tool provides fast, quantitative, and mechanistic insights into the acute and chronic effects of a compound on biofilm activity while requiring only minute quantities of the biocide.


Asunto(s)
Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Calorimetría/métodos , Pruebas de Sensibilidad Microbiana/métodos , 2,4-Dinitrofenol/farmacología , Adenosina Trifosfato/metabolismo , Calorimetría/instrumentación , Ciprofloxacina/farmacología , Formaldehído/farmacología , Kanamicina/farmacología , Pruebas de Sensibilidad Microbiana/instrumentación , Microcomputadores , Pseudomonas putida/efectos de los fármacos , Pseudomonas putida/crecimiento & desarrollo , Tetraciclina/farmacología
6.
Rev Sci Instrum ; 91(11): 113001, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-33261465

RESUMEN

We developed a table-top setup to perform magneto-optical pump-probe measurements with the possibility to independently tune the photon-energy of both pump and probe beams in the 0.5 eV-3.5 eV range. Our apparatus relies on a commercial turn-key amplified laser system, able to generate light pulses with duration shorter than or comparable to 100 fs throughout the whole spectral range. The repetition rate of the source can be modified via the computer in the 1 kHz to 1 MHz range. A commercial balanced detector is connected to a high-frequency digitizer, allowing for a highly-sensitive detection scheme: rotations of the probe polarization as small as 70 µdeg can be measured. Additionally, a DC magnetic field as high as 9 T and voltages in the kV regime can be applied on the sample. A cryostat allows us to precisely set the temperature of the specimen in the 4 K-420 K interval. We prove the performance of our setup by measuring the ultrafast demagnetization of a cobalt crystal as a function of a wide variety of experimental parameters.

7.
Thorax ; 64(11): 963-7, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19720607

RESUMEN

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is associated with an increased risk of lung cancer, independently of smoking. However, the relationship between COPD and total cancer mortality is less certain. A study was undertaken to investigate the association between COPD and total cancer mortality and to determine whether the use of statins, which have been associated with cancer risk in other settings, modified this relationship. METHODS: The study included 3371 patients with peripheral arterial disease who underwent vascular surgery between 1990 and 2006; 1310 (39%) had COPD and the rest did not. The primary end point was cancer mortality (lung and extrapulmonary) over a median follow-up of 5 years. RESULTS: COPD was associated with an increased risk of both lung cancer mortality (hazard ratio (HR) 2.06; 95% CI 1.32 to 3.20) and extrapulmonary cancer mortality (HR 1.43; 95% CI 1.06 to 1.94). The excess risk was mostly driven by patients with moderate and severe COPD. There was a trend towards a lower risk of cancer mortality among patients with COPD who used statins compared with patients with COPD who did not use statins (HR 0.57; 95% CI 0.32 to 1.01). Interestingly, the risk of extrapulmonary cancer mortality was lower among statin users with COPD (HR 0.49; 95% CI 0.24 to 0.99). CONCLUSIONS: COPD was associated with increased lung and extrapulmonary cancer mortality in this large cohort of patients with peripheral arterial disease undergoing vascular surgery. The risk of lung cancer mortality increased with progression of COPD. Statins were associated with a reduced risk of extrapulmonary cancer mortality in patients with COPD.


Asunto(s)
Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Neoplasias/mortalidad , Enfermedad Pulmonar Obstructiva Crónica/mortalidad , Anciano , Causas de Muerte , Métodos Epidemiológicos , Femenino , Humanos , Neoplasias Pulmonares/etiología , Neoplasias Pulmonares/mortalidad , Masculino , Neoplasias/etiología , Enfermedades Vasculares Periféricas/complicaciones , Enfermedades Vasculares Periféricas/tratamiento farmacológico , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Índice de Severidad de la Enfermedad
8.
Cytogenet Genome Res ; 124(2): 121-7, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19420923

RESUMEN

Giant cell tumor of bone (GCTB) is characterized cytogenetically by frequent telomeric associations (tas). To explore the mechanisms behind the formation of tas in GCTB and to investigate their karyotypic consequences, the frequencies of tas and clonal aberrations other than tas in 20 GCTBs were compared to telomere length and status, as assessed by quantitative PCR, fluorescence in situ hybridization (FISH), and expression levels of four genes involved in telomere maintenance. Based on the G-banding results, the tumors were divided into two groups, one with a high frequency of tas and one with a low frequency. Clonal aberrations were found to be restricted to the group with a high level of tas, and the same group showed a significantly larger reduction in telomere length in tumor cells compared to peripheral blood cells. Furthermore, 65 out of 66 tas analyzed by FISH were negative for telomeric sequences. The expression levels of TERT, TERF1, TERF2, and POT1 did not correlate with telomere length or the frequency of tas. Thus, the present findings provide strong support for the notion that decreased telomere length is a prerequisite for tas in GCTBs and that the clonal changes occurring in GCTBs are derived from tas.


Asunto(s)
Aberraciones Cromosómicas , Tumor Óseo de Células Gigantes/genética , Telómero/metabolismo , Adolescente , Adulto , Bandeo Cromosómico , Células Clonales , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Hibridación Fluorescente in Situ , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Complejo Shelterina , Telomerasa/genética , Telomerasa/metabolismo , Proteínas de Unión a Telómeros/genética , Proteínas de Unión a Telómeros/metabolismo , Proteína 2 de Unión a Repeticiones Teloméricas/genética , Proteína 2 de Unión a Repeticiones Teloméricas/metabolismo
9.
Phys Rev E Stat Nonlin Soft Matter Phys ; 79(3 Pt 2): 036601, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19392067

RESUMEN

We investigate the ratchet dynamics of solitons of a sine-Gordon system with additive inhomogeneities. We show by means of a collective coordinate approach that the soliton moves like a particle in an effective potential which is a result of the inhomogeneities. Different degrees of freedom of the soliton are used as collective coordinates in order to study their influence on the motion of the soliton. The collective coordinates considered are the soliton position, its width and offset, and the height of the spikes that appear on the soliton. The results of the theory are compared with numerical simulations of the full system.

10.
Phys Rev E Stat Nonlin Soft Matter Phys ; 79(1 Pt 2): 016207, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19257122

RESUMEN

We investigate homogeneous and inhomogeneous sine-Gordon ratchet systems in which a temporal symmetry and the spatial symmetry, respectively, are broken. We demonstrate that in the inhomogeneous systems with ac driving the soliton dynamics is chaotic in certain parameter regions, although the soliton motion is unidirectional. This is qualitatively explained by a one-collective-coordinate theory which yields an equation of motion for the soliton that is identical to the equation of motion for a single particle ratchet which is known to exhibit chaotic transport in its underdamped regime. For a quantitative comparison with our simulations we use a two-collective-coordinate (2CC) theory. In contrast to this, homogeneous sine-Gordon ratchets with biharmonic driving, which breaks a temporal shift symmetry, do not exhibit chaos. This is explained by a 2CC theory which yields two ODEs: one is linear, the other one describes a parametrically driven oscillator which does not exhibit chaos. The latter ODE can be solved by a perturbation theory which yields a hierarchy of linear equations that can be solved exactly order by order. The results agree very well with the simulations.

11.
Cytopathology ; 20(5): 304-14, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18637810

RESUMEN

BACKGROUND: Low-grade fibromyxoid sarcoma (LGFMS) is an uncommon neoplasm with bland morphology and an indolent clinical course, although metastases may develop in approximately 5-10% of the cases. The diagnosis of LGFMS can be difficult to render from fine needle aspiration cytology (FNAC) alone because of morphological overlap with other spindle cell and myxoid lesions. OBJECTIVE: To determine cytological criteria for LGFMS by reviewing FNAC aspirates in eight cases and to compare the findings with those in subsequent histological sections. METHODS: FNAC slides were reviewed from eight patients with subsequently excised tumours diagnosed as LGFMS. Of these patients, six also had core needle biopsies (CNB). Cytogenetic and/or molecular analysis was carried on all tumours. RESULTS: The patients were six men and two women ranging in age from 26 to 78 years. Tumours arose in the deep soft tissues of the thigh (n = 5), shoulder girdle (n = 1) or upper arm (n = 1) and one in the subcutaneous tissue of the abdominal wall. Cytological features included clusters of bland spindle and round/polygonal cells embedded in a collagenous and myxoid matrix along with dissociated, uniform or slightly/moderately pleomorphic spindle cells, bare nuclei and fragments of collagen and myxoid tissue in varying proportions. Unequivocal sarcoma was diagnosed in two aspirates, but mitoses were absent in all cases. In three cases, the diagnosis was inconclusive with regard to benignity or malignancy, while three were erroneously diagnosed as benign spindle cell lesions. Although the diagnosis was suggested on three of six CNB, these presented similar diagnostic problems. CONCLUSIONS: There were no cytomorphological findings in FNAC to allow for a clear cut separation of LGFMS from other spindle cell or myxoid lesions, but high-grade sarcoma could be excluded. Surgical (incisional or excisional) biopsy or, alternatively, examination of RT-PCR for the FUS/CREB3L or FUS/CREB3L1 fusion transcripts may be necessary to obtain a correct diagnosis.


Asunto(s)
Biopsia con Aguja Fina , Fibroma , Sarcoma , Neoplasias de los Tejidos Blandos , Adulto , Anciano , Citogenética , Femenino , Fibroma/diagnóstico , Fibroma/patología , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Sarcoma/diagnóstico , Sarcoma/patología , Neoplasias de los Tejidos Blandos/diagnóstico , Neoplasias de los Tejidos Blandos/patología
12.
J Microbiol Methods ; 74(2-3): 74-81, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18502524

RESUMEN

The partial dissipation of Gibbs energy as heat reflects the metabolic dynamic of biofilms in real time and may also allow quantitative conclusions about the chemical composition of the biofilm via Hess' law. Presently, the potential information content of heat is hardly exploited due to the low flexibility, the low throughput and the high price of conventional calorimeters. In order to overcome the limitations of conventional calorimetry a miniaturized calorimeter for biofilm investigations has been evaluated. Using four thermopiles a heat production with spatial and temporal resolutions of 2.5 cm(-1) and 2 s(-1) could be determined. The limit of detection of the heat flow measurement was 20 nW, which corresponds to the cell density of an early stage biofilm (approx. 3x10(5) cells cm(-2)). By separating biofilm cultivation from the actual heat measurement, a high flexibility and a much higher throughput was achieved if compared with conventional calorimeters. The approach suggested allows cultivation of biofilms in places of interest such as technological settings as well as in nature followed by highly efficient measurements in the laboratory. Functionality of the miniaturized calorimeter was supported by parallel measurements with confocal laser scanning microscopy and a fiber optic based oxygen sensor using the oxycaloric equivalent (-460 kJ mol-O2(-1)).


Asunto(s)
Biopelículas , Calorimetría/métodos , Pseudomonas putida/fisiología , Técnicas Biosensibles , Microscopía Confocal , Oxígeno/análisis , Sensibilidad y Especificidad , Factores de Tiempo
13.
Oncogene ; 25(53): 7106-16, 2006 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-16732325

RESUMEN

Ring chromosomes and/or giant marker chromosomes have been observed in a variety of human tumor types, but they are particularly common in a subgroup of mesenchymal tumors of low-grade or borderline malignancy. These rings and markers have been shown to contain amplified material predominantly from 12q13-15, but also sequences from other chromosomes. Such amplified sequences were mapped in detail by genome-wide array comparative genomic hybridization in ring-containing tumor samples from soft tissue (n = 15) and bone (n = 6), using tiling resolution microarrays, encompassing 32 433 bacterial artificial chromosome clones. The DNA copy number profiles revealed multiple amplification targets, in many cases highly discontinuous, leading to delineation of large numbers of very small amplicons. A total number of 356 (median size: 0.64 Mb) amplicons were seen in the soft tissue tumors and 90 (median size: 1.19 Mb) in the bone tumors. Notably, more than 40% of all amplicons in both soft tissue and bone tumors were mapped to chromosome 12, and at least one of the previously reported recurrent amplifications in 12q13.3-14.1 and 12q15.1, including SAS and CDK4, and MDM2, respectively, were present in 85% of the soft tissue tumors and in all of the bone tumors. Although chromosome 12 was the only chromosome displaying recurrent amplification in the bone tumors, the soft tissue tumors frequently showed recurrent amplicons mapping to other chromosomes, that is, 1p32, 1q23-24, 3p11-12, 6q24-25 and 20q11-12. Of particular interest, amplicons containing genes involved in the c-jun NH2-terminal kinase/mitogen-activated protein kinase pathway, that is, JUN in 1p32 and MAP3K7IP2 (TAB2) in 6q24-25, were found to be independently amplified in eight of 11 cases with 12q amplification, providing strong support for the notion that aberrant expression of this pathway is an important step in the dedifferentiation of liposarcomas.


Asunto(s)
Neoplasias Óseas/genética , Cromosomas Artificiales Bacterianos/genética , Genoma Humano/genética , Cromosomas en Anillo , Neoplasias de los Tejidos Blandos/genética , Adulto , Anciano , Anciano de 80 o más Años , Niño , Femenino , Dosificación de Gen/genética , Perfilación de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos
14.
Phys Rev E Stat Nonlin Soft Matter Phys ; 75(3 Pt 2): 036615, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17500817

RESUMEN

We extend our studies of thermal diffusion of nontopological solitons to anharmonic Fermi-Pasta-Ulam-type chains with additional long-range couplings. The observed superdiffusive behavior in the case of nearest-neighbor interaction turns out to be the dominating mechanism for the soliton diffusion on chains with long-range interactions. Using a collective variable technique in the framework of a variational analysis for the continuum approximation of the chain, we derive a set of stochastic integrodifferential equations for the collective variables (CVs) soliton position and the inverse soliton width. This set can be reduced to a statistically equivalent set of Langevin-type equations for the CV, which shares the same Fokker-Planck equation. The solution of the Langevin set and the Langevin dynamics simulations of the discrete system agree well and demonstrate that the variance of the soliton increases stronger than linearly with time (superdiffusion). This result for the soliton diffusion on anharmonic chains with long-range interactions reinforces the conjecture that superdiffusion is a generic feature of nontopological solitons.

15.
J Voice ; 21(2): 151-6, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16504470

RESUMEN

SUMMARY: Bilateral (quasi) symmetrical lesions of the anterior third of the vocal folds, commonly called vocal fold nodules (VFNs) are the most frequent vocal fold lesions in childhood caused by vocal abuse and hyperfunction. This study evaluates their long-term genesis with or without surgery and voice therapy. A group of 91 postmutational adolescents (mean age, 16 years), in whom VFNs were diagnosed in childhood, were questioned to analyze the evolution of their complaints. Thirty four of them could be clinically reexamined by means of the European Laryngological Society-protocol, including a complete laryngological investigation and voice assessment. A total of 21% of the questioned group (n=91) had voice complaints persisting into postpubescence with a statistically significant difference (P

Asunto(s)
Pliegues Vocales/patología , Trastornos de la Voz/patología , Trastornos de la Voz/fisiopatología , Adolescente , Factores de Edad , Niño , Preescolar , Progresión de la Enfermedad , Femenino , Humanos , Laringoscopía/métodos , Masculino , Índice de Severidad de la Enfermedad , Trastornos de la Voz/diagnóstico , Calidad de la Voz
16.
Cytogenet Genome Res ; 112(1-2): 60-6, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16276091

RESUMEN

Chromosome segment 12q13-->q15 recombines with many different chromosome bands in lipomas and at least ten recurrent translocations have been identified. The HMGA2 gene is often rearranged, but little is known about the molecular consequences at other breakpoints. Fusion genes between HMGA2 (12q14-->q15) and LPP (3q27-->q28), LHFP (13q12) and CMKOR1 (2q37) have been reported. In the present study, eight lipomas with rearrangements involving chromosome bands 12q14-->q15 and 5q32-->q33 were analyzed. In chromosome 5, five of the cases had a breakpoint in the 5' part of EBF in 5q33, while three cases had breakpoints located about 200 kb 3' of EBF. In chromosome 12, the breakpoints clustered to the region of HMGA2. Four cases had breaks within the gene and four had breaks 5' to HMGA2 where the gene BC058822 is located. Two versions of an HMGA2/EBF fusion transcript were detected in one case; one transcript was in frame and the other out of frame. Identical EBF/BC058822 fusion transcripts, seen in two cases, one of which also had the HMGA2/EBF transcript, were out of frame and resulted in truncation of EBF. Since EBF and HMGA2 have different orientations, the findings must be explained by complex aberrations including multiple breaks. The combined data indicate that the pathogenetically significant event is fusion, truncation or transcriptional activation of HMGA2, but it can not be excluded that EBF, which has been implicated in adipogenesis, contributes to the tumor development.


Asunto(s)
Cromosomas Humanos Par 12 , Cromosomas Humanos Par 5 , Proteína HMGA2/genética , Lipoma/genética , Adulto , Anciano , Secuencia de Bases , Mapeo Cromosómico , Cartilla de ADN , Femenino , Fusión Génica , Reordenamiento Génico , Marcadores Genéticos , Humanos , Cariotipificación , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Eliminación de Secuencia , Transcripción Genética , Activación Transcripcional
17.
Cytogenet Genome Res ; 115(3-4): 283-8, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17124411

RESUMEN

Dermatofibrosarcoma protuberans (DFSP) is a rare, slow-growing, low-grade dermal tumor. Cytogenetic and FISH studies have revealed that the chromosomal rearrangements characteristic of DFSP tumors involve both translocations and the formation of a supernumerary ring derived from chromosomes 17 and 22. The t(17;22) (q22;q13.1) translocation generates a gene fusion between COL1A1 and PDGFB, which serves as a diagnostic marker of DFSP. In the present study we performed array-CGH (aCGH) analysis on ten DFSP tumors. The COL1A1 region at 17q was gained in 71% (5/7) of the samples and the PDGFB region at 22q was gained in 43% (3/7) of the individual samples. In addition to the 17q and 22q gains, altogether 17 minimal common regions of gain and one region of loss were detected.


Asunto(s)
Biología Computacional/métodos , Dermatofibrosarcoma/genética , Hibridación de Ácido Nucleico/métodos , Neoplasias Cutáneas/genética , Adulto , Cromosomas/ultraestructura , Colágeno Tipo I/genética , Cadena alfa 1 del Colágeno Tipo I , Análisis Citogenético/métodos , Femenino , Dosificación de Gen , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/metabolismo , Translocación Genética
18.
Cytogenet Genome Res ; 114(2): 126-30, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16825763

RESUMEN

Isochromosome 7q - i(7q) - is seen in a wide variety of hematologic malignancies and solid tumors, often as a secondary change to a characteristic primary translocation. Despite its high frequency, nothing is known about the formation and the pathogenetic outcome of this abnormality. To address these issues, we performed a detailed fluorescence in situ hybridization (FISH) investigation of four acute lymphoblastic leukemias, one acute myeloid leukemia, and two myxoid liposarcomas with i(7q). Using FISH with bacterial artificial chromosomes (BACs) mapping between 7p12.2 and 7q11.2, the breakpoints (BPs) in all seven cases were shown to cluster to an approximately 340 kb segment at 7p11.2, covered by the overlapping BAC probes RP11-760D2 and RP11-10F11. Thus, the i(7q) should formally be designated idic(7) (p11.2). In one of the cases, FISH with fosmids could narrow down the BP further to an 80-kb sequence delineated by G248P81983A10 and G248P8793H7. No known genes are located in the 340-kb BP cluster region, indicating that the idic(7)(p11.2) does not result in a fusion or deregulation of genes in this segment. The pathogenetically important outcome is thus likely to be an altered gene expression because of copy number changes. The clustering of breakpoints might be due to frequent intrachromosomal duplicons in the BP region.


Asunto(s)
Rotura Cromosómica/genética , Cromosomas Humanos Par 7/genética , Isocromosomas/genética , Leucemia/genética , Leucemia/patología , Liposarcoma Mixoide/genética , Liposarcoma Mixoide/patología , Enfermedad Aguda , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Masculino , Persona de Mediana Edad
19.
Cytogenet Genome Res ; 115(2): 99-106, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17065789

RESUMEN

Amplification of 11q13 DNA sequences and overexpression of CCND1 are common findings in head and neck squamous cell carcinoma (HNSCC), identified in about 30% of the cases. However, little is known about initiation of the amplification and the organization of the amplicon. In order to study the structure of the amplicon in more detail and to learn more about the mechanisms involved in its initiation, prometaphase, metaphase, and anaphase fluorescence in situ hybridization (FISH) with 40 BAC clones spanning a 16-Mb region in chromosome bands 11q12.2 to 11q13.5 was performed in nine HNSCC cell lines with homogeneously staining regions. FISH analysis showed that the size of the amplicon varied among the nine cell lines, the smallest being 2.12 Mb and the largest 8.97 Mb. The smallest overlapping region of amplification was approximately 1.61 Mb, covering the region from BAC 729E14 to BAC 102B19. This region contained several genes previously shown to be amplified and overexpressed in HNSCC, including CCDN1, CTTN, SHANK2, and ORAOV1. The cell lines were also used to study the internal structure of the amplicon. Various patterns of amplified DNA sequences within the amplicon were found among the nine cell lines. Even within the same cell line, different amplicon structures could be found in different cell populations, indicating that the mechanisms involved in the development of the amplicons in HNSCC were more complex than previously assumed. The frequent finding of inverted repeats within the amplicons, however, suggests that breakage-fusion-bridge cycles are important in the initiation, but the fact that such repeats constituted only small parts of the amplicons indicate that they are further rearranged during tumor progression.


Asunto(s)
Carcinoma de Células Escamosas/genética , Cromosomas Humanos Par 11/genética , ADN de Neoplasias/genética , Amplificación de Genes , Neoplasias de Cabeza y Cuello/genética , Hibridación Fluorescente in Situ , Anafase , Línea Celular Tumoral/ultraestructura , Bandeo Cromosómico , Rotura Cromosómica , Cromosomas Artificiales Bacterianos , Cromosomas Humanos Par 11/ultraestructura , Reparación del ADN , Progresión de la Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Metafase , Secuencias Repetitivas de Ácidos Nucleicos
20.
Phys Rev E Stat Nonlin Soft Matter Phys ; 73(5 Pt 2): 056610, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16803060

RESUMEN

The DNLS model including Kac-Baker long-range interactions and nonlinear damping exhibits prominent effects in computer simulations. The combination of long-range forces and damping yields a periodic pattern of stationary breathers from an originally uniformly distributed background. The inverse interaction radius determines the periodicity which can be understood in the quasicontinuum approximation of the system. For the undamped system, we investigate the impact of the long-range interactions on the transition to the persistent-breather phase, which only depends on the energy and the norm of the DNLS. Using Monte Carlo techniques, we can monitor the localization strength as a function of the the long-range radius and the system temperature, which is formally negative in the persistent-breather phase.

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