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41.
Gianmauro Numico Antonella Cristofano Alessandro Mozzicafreddo Olga Elisabetta Cursio Pierfrancesco Franco Giulia Courthod Antonio Trogu Alessandra Malossi Mariella Cucchi Zuzana Sirotovà Maria Rosa Alvaro Anna Stella Fulvia Grasso Silvia Spinazzé Nicola Silvestris 《PloS one》2015,10(3)
Background
Cancer patients are frequently admitted to hospital due to acute conditions or refractory symptoms. This occurs through the emergency departments and requires medical oncologists to take an active role. The use of acute-care hospital increases in the last months of life.Patients and methods
We aimed to describe the admissions to a medical oncology inpatient service within a 16-month period with respect to patients and tumor characteristics, and the outcome of the hospital stay.Results
672 admissions of 454 patients were analysed. The majority of admissions were urgent (74.1%), and were due to uncontrolled symptoms (79.6%). Among the chief complaints, dyspnoea occurred in 15.7%, pain in 15.2%, and neurological symptoms in 14.5%. The majority of the hospitalizations resulted in discharge to home (60.6%); in 26.5% the patient died and in 11.0% was transferred to a hospice. Admissions due to symptoms correlated with a longer hospital stay and a higher incidence of in-hospital death.Conclusion
We suggest that hospital use is not necessarily a sign of inappropriately aggressive care: inpatient care is probably an unavoidable step in the cancer trajectory. Optimization of inpatient supportive procedures should be a specific task of modern medical oncology. 相似文献42.
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44.
Montanaro L Vici M Donati G Ceccarelli C Santini D Treré D Derenzini M 《Histology and histopathology》2007,22(7):769-775
Recent data challenge the relevance of the RB pathway to cancer based on RB inactivation, at least in breast tumors. To obtain information on the actual role of the components of the RB pathway in tumor progression we decided to investigate whether their quantitative changes were associated with variations in the level of RB phosphorylation in human breast cancer. A series of 68 human primary breast carcinomas was studied. Five cases were excluded from the study due to their lack of RB expression. In the remaining 63 cases the expression of cyclin D1, cdk4, cyclin E, and INK4a mRNA was assessed by real-time RT-PCR. The level of RB phosphorylated protein (ppRB) and p27 expression was immunohistochemically analyzed by measuring the percentage of stained cells (labeling index, LI). Cell proliferation rate was measured by Ki67 LI evaluation. The ppRB LI ranged from 5.2 to 73.8 and, as expected, was strongly related to the Ki67 LI (r=0.80; p<0.001). The expression of cyclin D1 mRNA, expressed in arbitrary units (a. u.), ranged from 1.15 to 123.0 and was inversely related to the ppRB LI (p=0.021) and Ki67 LI (p<0.001). Neither the cdk4 (range from 0.07 to 1.13 a. u.) nor the cyclin E (range from 0.13 to 9.27 a. u.) mRNA expression was significantly associated with the ppRB LI (p=0.962 and p=0.103, respectively). Cyclin E was related to Ki67 LI (p=0.022). Both INK4a mRNA (range from 0.01 to 0.60 a. u.) and p27 (LI from 0.0 to 73.1) values were inversely related to the ppRB LI (p=0.022 and p=0.014, respectively). Cyclin D1, cdk4, and cyclin E mRNA expressions were not significantly related to one another. In human primary breast cancers, the expression levels of the factors known to facilitate the cell cycle progression by RB protein phosphorylation were not positively related to ppRB-LI. Pathological increases of cyclin D, cdk4, and cyclin E are very likely associated with other biological functions other than their well-established action on cell cycle progression. 相似文献
45.
Paula Medone Soledad Ceccarelli Paul E. Parham Andreína Figuera Jorge E. Rabinovich 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2015,370(1665)
Chagas disease, caused by the parasite Trypanosoma cruzi, is the most important vector-borne disease in Latin America. The vectors are insects belonging to the Triatominae (Hemiptera, Reduviidae), and are widely distributed in the Americas. Here, we assess the implications of climatic projections for 2050 on the geographical footprint of two of the main Chagas disease vectors: Rhodnius prolixus (tropical species) and Triatoma infestans (temperate species). We estimated the epidemiological implications of current to future transitions in the climatic niche in terms of changes in the force of infection (FOI) on the rural population of two countries: Venezuela (tropical) and Argentina (temperate). The climatic projections for 2050 showed heterogeneous impact on the climatic niches of both vector species, with a decreasing trend of suitability of areas that are currently at high-to-moderate transmission risk. Consequently, climatic projections affected differently the FOI for Chagas disease in Venezuela and Argentina. Despite the heterogeneous results, our main conclusions point out a decreasing trend in the number of new cases of Tr. cruzi human infections per year between current and future conditions using a climatic niche approach. 相似文献
46.
Fission yeast MO25 protein is localized at SPB and septum and is essential for cell morphogenesis 下载免费PDF全文
Kanai M Kume K Miyahara K Sakai K Nakamura K Leonhard K Wiley DJ Verde F Toda T Hirata D 《The EMBO journal》2005,24(17):3012-3025
Cell morphogenesis is of fundamental significance in all eukaryotes for development, differentiation, and cell proliferation. In fission yeast, Drosophila Furry-like Mor2 plays an essential role in cell morphogenesis in concert with the NDR/Tricornered kinase Orb6. Mutations of these genes result in the loss of cell polarity. Here we show that the conserved proteins, MO25-like Pmo25, GC kinase Nak1, Mor2, and Orb6, constitute a morphogenesis network that is important for polarity control and cell separation. Intriguingly, Pmo25 was localized at the mitotic spindle pole bodies (SPBs) and then underwent translocation to the dividing medial region upon cytokinesis. Pmo25 formed a complex with Nak1 and was required for both the localization and kinase activity of Nak1. Pmo25 and Nak1 in turn were essential for Orb6 kinase activity. Further, the Pmo25 localization at the SPBs and the Nak1-Orb6 kinase activities during interphase were under the control of the Cdc7 and Sid1 kinases in the septation initiation network (SIN), suggesting a functional linkage between SIN and the network for cell morphogenesis/separation following cytokinesis. 相似文献
47.
48.
Blamey CJ Ceccarelli C Naik UP Bahnson BJ 《Protein science : a publication of the Protein Society》2005,14(5):1214-1221
Calcium- and integrin-binding protein 1 (CIB1) is involved in the process of platelet aggregation by binding the cytoplasmic tail of the alpha(IIb) subunit of the platelet-specific integrin alpha(Iib)beta(3). Although poorly understood, it is widely believed that CIB1 acts as a global signaling regulator because it is expressed in many tissues that do not express integrin alpha(Iib)beta(3). We report the structure of human CIB1 to a resolution of 2.3 A, crystallized as a dimer. The dimer interface includes an extensive hydrophobic patch in a crystal form with 80% solvent content. Although the dimer form of CIB1 may not be physiologically relevant, this intersub-unit surface is likely to be linked to alpha(IIb) binding and to the binding of other signaling partner proteins. The C-terminal domain of CIB1 is structurally similar to other EF-hand proteins such as calmodulin and calcineurin B. Despite structural homology to the C-terminal domain, the N-terminal domain of CIB1 lacks calcium-binding sites. The structure of CIB1 revealed a complex with a molecule of glutathione in the reduced state bond to the N-terminal domain of one of the two subunits poised to interact with the free thiol of C35. Glutathione bound in this fashion suggests CIB1 may be redox regulated. Next to the bound GSH, the orientation of residues C35, H31, and S48 is suggestive of a cysteine-type protein phosphatase active site. The potential enzymatic activity of CIB1 is discussed and suggests a mechanism by which it regulates a wide variety of proteins in cells in addition to platelets. 相似文献
49.
Odile?Sergent Aldo?Tomasi Daniela?Ceccarelli Alberto?Masini Hans?Nohl Pierre?Cillard Josiane?Cillard Yuri?A.?Vladimirov Andrey?V.?KozlovEmail author 《Biometals》2005,18(6):567-575
Iron overload aggravates tissue damage caused by ischemia and ethanol intoxication. The underlying mechanisms of this phenomenon
are not yet clear. To clarify these mechanisms we followed free iron (“loosely” bound redox-active iron) concentration in
livers from rats subjected to experimental iron overload, acute ethanol intoxication, and ex vivo warm ischemia. The levels of free iron in non-homogenized liver tissues, liver homogenates, and hepatocyte cultures were
analyzed by means of EPR spectroscopy. Ischemia gradually increased the levels of endogenous free iron in liver tissues and
in liver homogenates. The increase was accompanied by the accumulation of lipid peroxidation products. Iron overload alone,
known to increase significantly the total tissue iron, did not affect either free iron levels or lipid peroxidation. Homogenization
of iron-loaded livers, however, resulted in the release of a significant portion of free iron from endogenous depositories.
Acute ethanol intoxication increased free iron levels in liver tissue and diminished the portion of free iron releasing during
homogenization. Similarly to liver tissue, the primary hepatocyte culture loaded with iron in vitro released significantly more free iron during homogenization compared to non iron-loaded hepatocyte culture. Analyzing three
possible sources of free iron release under these experimental conditions in liver cells, namely ferritin, intracellular transferrin-receptor
complex and heme oxygenase, we suggest that redox active free iron is released from ferritin under ischemic conditions whereas
ethanol and homogenization facilitate the release of iron from endosomes containing transferrin-receptor complexes. 相似文献
50.
Automatic generation of accurate subject-specific bone finite element models to be used in clinical studies 总被引:5,自引:0,他引:5
Most of the finite element models of bones used in orthopaedic biomechanics research are based on generic anatomies. However, in many cases it would be useful to generate from CT data a separate finite element model for each subject of a study group. In a recent study a hexahedral mesh generator based on a grid projection algorithm was found very effective in terms of accuracy and automation. However, so far the use of this method has been documented only on data collected in vitro and only for long bones. The present study was aimed at verifying if this method represents a procedure for the generation of finite element models of human bones from data collected in vivo, robust, accurate, automatic and general enough to be used in clinical studies. Robustness, automation and numerical accuracy of the proposed method were assessed on five femoral CT data sets of patients affected by various pathologies. The generality of the method was verified by processing a femur, an ileum, a phalanx, a proximal femur reconstruction, and the micro-CT of a small sample of spongy bone. The method was found robust enough to cope with the variability of the five femurs, producing meshes with a numerical accuracy and a computational weight comparable to those found in vitro. Even when the method was used to process the other bones the levels of mesh conditioning remained within acceptable limits. Thus, it may be concluded that the method presents a generality sufficient to cope with almost any orthopaedic application. 相似文献