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1.
Breast Cancer Res Treat ; 198(3): 545-553, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36807725

RESUMEN

PURPOSE: Evidence about routine treatment and outcome of patients with invasive lobular cancer (ILC) is limited, especially regarding metastatic disease. Here we present prospective real-world data of patients with metastatic ILC (mILC) as compared to patients with metastatic invasive ductal cancer (mIDC) receiving systemic therapy in routine care in Germany. METHODS: Prospective data on patient and tumor characteristics, treatments, and outcomes of patients with mILC (n = 466) and mIDC (n = 2100), recruited between 2007 and 2021 into the Tumor Registry Breast Cancer/OPAL were analyzed. RESULTS: Compared to mIDCs, patients with mILC were older at start of first-line treatment (median 69 vs. 63 years) and had more often lower grade (G1/G2: 72.8% vs. 51.2%), hormone receptor (HR)-positive (83.7% vs. 73.2%) and less often HER2-positive (14.2% vs. 28.6%) tumors, which metastasized more frequently to the bone (19.7% vs. 14.5%) or peritoneum (9.9% vs. 2.0%), and less frequently to the lungs (0.9% vs. 4.0%). Median OS of patients with mILC (n = 209) and mIDC (n = 1158) was 30.2 months [95% confidence interval (CI) 25.3, 36.0] and 33.7 months [95% CI 30.3, 37.9], respectively. Multivariate survival analysis did not show a significant prognostic impact of the histological subtype [HR mILC vs. mIDC 1.18 (95% CI 0.97-1.42)]. CONCLUSION: Overall, our real-world data confirm clinicopathological differences between mILC and mIDC breast cancer patients. Despite patients with mILC presenting with some favorable prognostic factors, ILC histopathology was not associated with a better clinical outcome in multivariate analysis, suggesting the need for more tailored treatment strategies for patients with the lobular subtype.


Asunto(s)
Neoplasias de la Mama , Carcinoma Ductal de Mama , Carcinoma Lobular , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Estudios Prospectivos , Estudios Retrospectivos , Receptor ErbB-2 , Carcinoma Lobular/patología , Carcinoma Ductal de Mama/patología , Pronóstico , Resultado del Tratamiento
2.
Colorectal Dis ; 21(7): 816-826, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30834622

RESUMEN

AIM: Published prognostic scores for metastatic colorectal cancer (mCRC) are based on data from highly selected patient subgroups with specified first-line treatments and may not be applicable to routine practice. We have therefore developed and validated the metastatic colorectal cancer score (mCCS) to predict overall survival (OS) for patients with mCRC. METHOD: A total of 1704 patients from the prospective, multicentre cohort study Tumour Registry Colorectal Cancer were separated into learning (n = 796) and validation (n = 908) samples. Using a multivariate Cox regression model, the six-factor mCCS was established. RESULTS: The six independent prognostic factors for survival are as follows: two or more metastatic sites at the start of first-line treatment, tumour grading ≥ G3 at primary diagnosis, residual tumour classification ≥ R1/unknown, lymph node ratio (of primary tumour) ≥ 0.4, tumour stage ≥ III/unknown at primary diagnosis and KRAS status mutated/unknown. The mCCS clearly separated the learning sample into three risk groups: zero to two factors (low risk), three factors (intermediate risk) and four to six factors (high risk). The prognostic performance of the mCCS was confirmed in the validation sample and additionally stratified a large sample of patients with known (K)RAS mutation status. CONCLUSION: The novel prognostic score, mCCS, clearly defines three prognostic groups for OS at start of first-line therapy. For oncologists, the mCCS represents a simple and easy-to-apply tool for routine clinical use, as it is based on objective tumour characteristics and can assist with treatment decision-making and communication of the prognosis to patients.


Asunto(s)
Neoplasias Colorrectales/mortalidad , Índice de Severidad de la Enfermedad , Anciano , Femenino , Alemania/epidemiología , Humanos , Estimación de Kaplan-Meier , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Sistema de Registros , Reproducibilidad de los Resultados
3.
J Am Chem Soc ; 123(19): 4519-29, 2001 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-11457238

RESUMEN

Self-assembled lamellar silica-surfactant mesophase composites have been prepared with crystal-like ordering in the silica frameworks using a variety of cationic surfactant species under hydrothermal conditions. These materials represent the first mesoscopically ordered composites that have been directly synthesized with structure-directing surfactants yielding highly ordered inorganic frameworks. One-dimensional solid-state 29Si NMR spectra, X-ray diffraction patterns, and infrared spectra show the progression of molecular organization in the self-assembled mesophases from structures with initially amorphous silica networks into sheets with very high degrees of molecular order. The silicate sheets appear to be two-dimensional crystals, whose structures and rates of formation depend strongly on the charge density of the cationic surfactant headgroups. Two-dimensional solid-state heteronuclear and homonuclear NMR measurements show the molecular proximities of the silica framework sites to the structure-directing surfactant molecules and establish local Si-O-Si bonding connectivities in these materials.

4.
Science ; 269(5229): 1416-20, 1995 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-17731152

RESUMEN

Ordering at short-length scales is a universal feature of the glassy state. Experiments on boron oxide and other materials indicate that ordering on mesoscopic-length scales may also be universal. The high-resolution nuclear magnetic resonance (NMR) measurements of oxygen in boron oxide glass presented here provide evidence for structural units responsible for ordering on short- and intermediate-length scales. At the molecular level, planar BO(3/2) units accounted for the local ordering. Oxygen-17 NMR spectra resolved detailed features of the inclusion of these units in boroxol rings, oxygen bridging two rings, and oxygen shared between two nonring BO(3/2) units. On the basis of these and corroborative boron-11 NMR and scattering results, boron oxide glass consists of domains that are rich or poor in boroxol rings; these domains are proposed to be the structural basis of intermediate-range order in glassy boron oxide.

5.
Science ; 261(5126): 1299-303, 1993 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-17731857

RESUMEN

A model is presented to explain the formation and morphologies of surfactant-silicate mesostructures. Three processes are identified: multidentate binding of silicate oligomers to the cationic surfactant, preferential silicate polymerization in the interface region, and charge density matching between the surfactant and the silicate. The model explains present experimental data, including the transformation between lamellar and hexagonal mesophases, and provides a guide for predicting conditions that favor the formation of lamellar, hexagonal, or cubic mesostructures. Model Q(230) proposed by Mariani and his co-workers satisfactorily fits the x-ray data collected on the cubic mesostructure material. This model suggests that the silicate polymer forms a unique infinite silicate sheet sitting on the gyroid minimal surface and separating the surfactant molecules into two disconnected volumes.

6.
Chromosoma ; 98(5): 358-67, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2612294

RESUMEN

During the first meiotic division in crane-fly spermatocytes, the two homologs of a metaphase bivalent each bear two sister kinetochores oriented toward the same pole. We have previously reported treatments that increase the percentage of metaphase bivalents in which one or both homologs have bipolar malorientations: kinetochore microtubules extending from a homolog toward both poles. The maloriented homologs lag at anaphase. Treatments that induce this behavior include: (a) recoverey from exposure to low temperatures or Colcemid or Nocodazole concentrations that prevent spindle formation but allow nuclear membrane breakdown, and (b) exposure to 6 degrees C, a temperature that permits spindle assembly but slows progression through meiosis. Giemsa staining methods reveal two 0.5 micron diameter dots at the centromeric region of each metaphase homolog; these often are more separated in maloriented homologs. This investigation was undertaken to assess whether this separation precedes the establishment of bipolar malorientation, and hence may be a cause of it, or is only a consequence of forces resulting from bipolar malorientation. Analysis showed that, in untreated cells, the average center-to-center distance between sister centromeric dots increases during the course of meiosis I. After the above-mentioned treatments, center-to-center distances similar to those normally seen in untreated half-bivalents at anaphase I were seen in bivalents, both after and before nuclear membrane breakdown. Longer exposure to temperatures that arrested meiosis increased the degree of dot separation. Based on our data, we conclude that normal orientation during the first meiotic division is aided by the close apposition of centromeric dots, and that a time-dependent maturation occurs causing centromeric dots to separate for the second meiotic division and facilitating orientation of sister kinetochores to opposite poles. If centromeric maturation occurs either prior to or during early stages of the first meiotic division, then it may contribute to persisting bipolar malorientation.


Asunto(s)
Centrómero/ultraestructura , Cromosomas/ultraestructura , Dípteros/genética , Meiosis , Microtúbulos/ultraestructura , Espermatozoides/fisiología , Animales , Colorantes Azulados , Bandeo Cromosómico , Masculino
7.
Environ Monit Assess ; 12(2): 99-114, 1989 May.
Artículo en Inglés | MEDLINE | ID: mdl-24249105

RESUMEN

Although structural change in many industralized countries has increased since the early 1970s, the environmental policy aspects of this change have hardly been investigated. The more pronounced the positive environmental effects of structural change become, the more positive will be the structure-oriented options of environmental policy.Using a set of four indicators, in this study thirty-one Eastern and Western industrialized countries are being tested with regard to economic structure and environmentally significant structural change. The authors come to the conclusion that the strong correlation between economic performance and environmental pollution, unequivocal in 1970, had become much weaker by 1985. The de-linking of economic growth from material-intensive industrial production processes is particularly evident. In some cases automatic environmental benefits ('environmental gratis effects') were generated in this way.However, the development profiles of the countries investigated differ greatly. There are countries, in particular Sweden, with absolute structural improvement in the ecological sense; countries like Japan and Norway with structural improvement relative to economic growth; and countries, including most Eastern and Southern European states, featuring no structural improvement or even environmentally negative structural change.The question is being left open to what extent the modernized economic structures are accompanied by 'modernized' forms of environmental pollution.

8.
Cell Motil Cytoskeleton ; 6(4): 428-38, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3757074

RESUMEN

We investigated the involvement of kinetochore microtubules (kMTs) in mediating chromosome-to-pole connections in crane-fly (Nephrotoma suturalis and Nephrotoma ferruginea) spermatocytes. Two experimental treatments were used to yield spindles with reduced numbers of nonkinetochore microtubules (nkMTs). Short-term (10-15 min) exposure of spermatocytes to 2 degrees C caused depolymerization of the majority of nkMTs, resulting in a kMT:(kMT + nkMT) ratio of 0.76. Long-term (24h) exposure to 2 degrees C followed by recovery at 6 degrees C resulted in a kMT:(kMT + nkMT) ratio of 0.55, the spindle having more nkMTs than a 2 degrees C-treated spindle but fewer than an untreated spindle, in which the kMT:(kMT + nkMT) ratio was 0.27. The numbers and lengths of kMTs in 6 degrees C-grown spindles were similar to those in untreated cells, suggesting that the overall inhibition of MT assembly at 6 degrees C apparently did not affect the mechanism by which kMTs are formed. We observed most kMTs of early anaphase spindles to be long (greater than 3 microns), and many extended to the polar regions of the spindle. Thus, the crane-fly spindle appears not to be as atypical as it was previously suggested to be.


Asunto(s)
Microtúbulos/ultraestructura , Huso Acromático/ultraestructura , Animales , Ciclo Celular , Frío , Dípteros , Larva , Masculino , Espermatocitos/citología , Espermatocitos/ultraestructura
9.
Cell Motil Cytoskeleton ; 6(5): 492-501, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3791426

RESUMEN

At metaphase in crane-fly primary spermatocytes, the two sister kinetochores at the centromere of each homologue in a bivalent normally are adjacent and face the same pole; one homologue has all its kinetochore microtubules (kMTs) extending toward one pole and its partner has all its kMTs extending toward the opposite pole. In contrast, during recovery from exposure to 2 degrees C, one or both homologues in many metaphase bivalents had bipolar malorientations: all kMTs of one kinetochore extended toward one pole and some or all those of its sister extended toward the other. Metaphase sister kinetochores that had most of their kMTs extending toward the same pole were adjacent, and those with most extending toward opposite poles were separated from each other. Distances between homologous centromeres were similar to those in properly oriented bivalents. Maloriented bivalents were tilted relative to the spindle axis, and analysis of living cells showed that tilted configurations were rare during prometaphase in untreated cells but frequently arose in cold-recovering cells as initial configurations, then persisted through metaphase. This was in contrast to unipolar configurations of bivalents (configurations suggesting orientation of both homologous centromeres toward the same pole), which always reoriented shortly after the configuration arose. We conclude that in cold-recovering cells, bipolar malorientations are more stable than unipolar malorientations, and the orientation process is affected such that bipolar malorientations arise in bivalents upon initial interaction with the spindle and persist through metaphase.


Asunto(s)
Cromosomas/fisiología , Frío , Dípteros/genética , Metafase , Espermatocitos/citología , Animales , Masculino , Meiosis
10.
J Cell Biol ; 98(3): 859-69, 1984 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6699088

RESUMEN

Exposing crane fly larvae to 6 degrees C or returning them to 22 degrees C after exposure to 6, 2, or 0.2 degrees C can induce any number of autosomes in their primary spermatocytes to lag near the spindle equator at anaphase. Autosomal laggards in cold-recovering cells are contained in bivalents until anaphase (Janicke, M. A., and J. R. LaFountain, 1982, Chromosoma, 85:619-631). We report here documentation that lagging autosomes in cold-treated and cold-recovering cells are maloriented. During meiosis I, half-bivalents usually associate with only one pole via kinetochore fibers, with sister chromatids being oriented to the same pole. In contrast, laggards had kinetochore microtubules (kMTs) extending from them toward both poles: one sister was oriented to one pole and the other had some or all of its kMTs extending toward the opposite pole. Bipolar malorientation of autosomal laggards also was observed in one untreated cell. The number of kMTs per half-bivalent was similar in lagging and non-lagging autosomes, and those kMTs were contained in long birefringent kinetochore fibers. The overall spindle structure in cold-recovering cells was similar to that observed in untreated anaphase cells. Giemsa-stained centromeric dots of sister chromatids were contiguous in non-laggards and separated in laggards at anaphase. We conclude that bipolar malorientations can exist at anaphase in chromosomes that remain paired until anaphase, that cold recovery increases the frequency of that anomaly, and that such malorientations may be one cause of anaphase lag.


Asunto(s)
Frío , Meiosis , Microtúbulos/fisiología , Huso Acromático/ultraestructura , Anafase , Animales , Dípteros , Masculino , Microscopía Electrónica , Espermatocitos/fisiología , Huso Acromático/fisiología
11.
Chromosoma ; 85(5): 619-31, 1982.
Artículo en Inglés | MEDLINE | ID: mdl-7128280

RESUMEN

Anaphase lagging of autosomes was observed in 6.1 +/- 5.4% of the primary spermatocytes in untreated larvae of the crane fly, Nephrotoma suturalis. Lagging was induced by exposure of larvae to 6 degrees C and during recovery at 22 degrees C from exposure to 0.2, 2, and 6 degrees C. The incidence of anaphase lag was maximal at 80 to 90 min of recovery. Induced lagging was observed at that recovery time after exposures of only 2.5 h to 2 or 0.2 degrees C, but its incidence increased with longer exposures. As many as 85% of the cells in anaphase contained autosomal laggards after 61 h at 2 degrees C and 80 to 90 min of recovery. At 2 degrees C, cells reached the prophase-prometaphase transition, but spindles did not appear to form. Those cells proceeded through prometaphase during recovery, reaching mid-anaphase after 80 to 90 min of recovery. Chromosomes that lagged at anaphase during recovery from 2 degrees C were observed in living cells to be half-bivalents derived from bivalents that congressed to the metaphase plate. One or both half-bivalents of any bivalent could lag. In some cells, one half-spindle had more half-bivalents than the other. Cells with autosomal laggards often did not cleave, and in uncleaved cells the second division employed spindles having two, three, or four poles. The basis of induced lagging might be a lapse in spindle attachment or motive force application at the start of anaphase or a failure of chromosomes to achieve proper orientation before the onset of anaphase.


Asunto(s)
Cromosomas/ultraestructura , Frío , Dípteros/genética , Meiosis , Animales , Larva/ultraestructura , Masculino , Espermatocitos/ultraestructura , Espermatogénesis , Factores de Tiempo
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