RESUMO
The SGI1 family integrative mobilizable elements, which are efficient agents in distribution of multidrug resistance in Gammaproteobacteria, have a complex, parasitic relationship with their IncC conjugative helper plasmids. Besides exploiting the transfer apparatus, SGI1 also hijacks IncC plasmid control mechanisms to time its own excision, replication and expression of self-encoded T4SS components, which provides advantages for SGI1 over its helpers in conjugal transfer and stable maintenance. Furthermore, SGI1 destabilizes its helpers in an unknown, replication-dependent way when they are concomitantly present in the same host. Here we report how SGI1 exploits the helper plasmid partitioning system to displace the plasmid and simultaneously increase its own stability. We show that SGI1 carries two copies of sequences mimicking the parS sites of IncC plasmids. These parS-like elements bind the ParB protein encoded by the plasmid and increase SGI1 stability by utilizing the parABS system of the plasmid for its own partitioning, through which SGI1 also destabilizes the helper plasmid. Furthermore, SGI1 expresses a small protein, Sci, which significantly strengthens this plasmid-destabilizing effect, as well as SGI1 maintenance. The plasmid-induced replication of SGI1 results in an increased copy-number of parS-like sequences and Sci expression leading to strong incompatibility with the helper plasmid.
Assuntos
Elementos de DNA Transponíveis , Salmonella , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Plasmídeos/genética , Salmonella/efeitos dos fármacos , Salmonella/genética , Farmacorresistência Bacteriana MúltiplaRESUMO
The implementation of supported metal catalysts heavily relies on the synergistic interactions between metal nanoparticles and the material they are dispersed on. It is clear that interfacial perimeter sites have outstanding skills for turning catalytic reactions over, however, high activity and selectivity of the designed interface-induced metal distortion can also obtain catalysts for the most crucial industrial processes as evidenced in this paper. Herein, the beneficial synergy established between designed Pt nanoparticles and MnO in the course of the reverse water gas shift (RWGS) reaction resulted in a Pt/MnO catalyst having ≈10â times higher activity compared to the reference Pt/SBA-15 catalyst with >99 % CO selectivity. Under activation, a crystal assembly through the metallic Pt (110) and MnO evolved, where the plane distance differences caused a mismatched-row structure in softer Pt nanoparticles, which was identified by microscopic and surface-sensitive spectroscopic characterizations combined with density functional theory simulations. The generated edge dislocations caused the Pt lattice expansion which led to the weakening of the Pt-CO bond. Even though MnO also exhibited an adverse effect on Pt by lowering the number of exposed metal sites, rapid desorption of the linearly adsorbed CO species governed the performance of the Pt/MnO in the RWGS.
RESUMO
The Salmonella genomic island 1 (SGI1) and its variants are mobilized by IncA and IncC conjugative plasmids. SGI1-family elements and their helper plasmids are effective transporters of multidrug resistance determinants. SGI1 exploits the transfer apparatus of the helper plasmid and hijacks its activator complex, AcaCD, to trigger the expression of several SGI1 genes. In this way, SGI1 times its excision from the chromosome to the helper entry and expresses mating pore components that enhance SGI1 transfer. The SGI1-encoded T4SS components and the FlhDC-family activator proved to be interchangeable with their IncC-encoded homologs, indicating multiple interactions between SGI1 and its helpers. As a new aspect of this crosstalk, we report here the helper-induced replication of SGI1, which requires both activators, AcaCD and FlhDCSGI1, and significantly increases the stability of SGI1 when coexists with the helper plasmid. We have identified the oriVSGI1 and shown that S004-repA operon encodes for a translationally coupled leader protein and an IncN2/N3-related RepA that are expressed under the control of the AcaCD-responsive promoter PS004. This replicon transiently maintains SGI1 as a 4-8-copy plasmid, not only stabilizing the island but also contributing to the fast displacement of the helper plasmid.
Assuntos
Proteínas de Bactérias/genética , Cromossomos Bacterianos/genética , Conjugação Genética/genética , Farmacorresistência Bacteriana Múltipla/genética , Sequências Repetitivas Dispersas/genética , Salmonella typhimurium/genética , Proteínas de Bactérias/metabolismo , DNA Helicases/genética , DNA Helicases/metabolismo , Replicação do DNA , Dosagem de Genes , Regulação Bacteriana da Expressão Gênica/genética , Genes Reporter , Integrases/metabolismo , Óperon/genética , Filogenia , Plasmídeos/genética , Regiões Promotoras Genéticas/genética , Biossíntese de Proteínas , Recombinases/metabolismo , Replicon/genética , Alinhamento de Sequência , Transativadores/genética , Transativadores/metabolismoRESUMO
The SGI1-family elements that are specifically mobilized by the IncA- and IncC-family plasmids are important vehicles of antibiotic resistance among enteric bacteria. Although SGI1 exploits many plasmid-derived conjugation and regulatory functions, the basic mobilization module of the island is unrelated to that of IncC plasmids. This module contains the oriT and encodes the mobilization proteins MpsA and MpsB, which belong to the tyrosine recombinases and not to relaxases. Here we report an additional, essential transfer factor of SGI1. This is a small RNA deriving from the 3'-end of a primary RNA that can also serve as mRNA of ORF S022. The functional domain of this sRNA named sgm-sRNA is encoded between the mpsA gene and the oriT of SGI1. Terminator-like sequence near the promoter of the primary transcript possibly has a regulatory function in controlling the amount of full-length primary RNA, which is converted to the active sgm-sRNA through consecutive maturation steps influenced by the 5'-end of the primary RNA. The mobilization module of SGI1 seems unique due to its atypical relaxase and the newly identified sgm-sRNA, which is required for the horizontal transfer of the island but appears to act differently from classical regulatory sRNAs.
Assuntos
Transferência Genética Horizontal , Ilhas Genômicas , RNA Bacteriano/genética , Salmonella/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Conjugação Genética , Farmacorresistência Bacteriana Múltipla , Plasmídeos/genética , Plasmídeos/metabolismo , RNA Bacteriano/metabolismo , Salmonella/metabolismoRESUMO
PURPOSE: To evaluate the potential benefits of digital variance angiography (DVA) in selective lower limb angiography and to compare the performance of 2 DVA algorithms (conventional DVA1 and the recently developed DVA2) to that of digital subtraction angiography (DSA). MATERIALS AND METHODS: From November 2019 to May 2020, 112 iodinated contrast media (ICM) and 40 carbon dioxide (CO2) angiograms were collected from 15 and 13 peripheral artery disease patients, respectively. The DVA files were retrospectively generated from the same unsubtracted source file as DSA. The objectively calculated contrast-to-noise ratio (CNR) and the subjective visual image quality of DSA, DVA1, and DVA2 images were statistically compared using the Wilcoxon signed-rank test. The images were evaluated by 6 radiologists (R.P.T., S.V., A.M.K., S.S.A., O.E., and J.S.) from 2 centers using a 5-grade Likert scale. RESULTS: Both DVA algorithms produced similar increase (at least 2-fold) in CNR values (P < .001) and significantly higher image quality scores than DSA, independent of the contrast agent used. The overall scores with ICM were 3.61 ± 0.05 for DSA, 4.30 ± 0.04 for DVA1, and 4.33 ± 0.04 for DVA2 (each P < .001 vs DSA). The scores for CO2 were 3.10 ± 0.14 for DSA, 3.63 ± 0.13 for DVA1 (P < .001 vs DSA), and 3.38 ± 0.13 for DVA2 (P < .05 vs DSA). CONCLUSIONS: DVA provides higher CNR and significantly better image quality in selective lower limb interventions irrespective of the contrast agent used. Between DVA algorithms, DVA1 is preferred because of its identical or better image quality than DVA2. DVA can potentially help the interventional decision process and its quality reserve might allow dose management (radiation/ICM reduction) in the future.
Assuntos
Extremidade Inferior , Doença Arterial Periférica , Angiografia Digital/métodos , Meios de Contraste , Humanos , Extremidade Inferior/irrigação sanguínea , Doença Arterial Periférica/diagnóstico por imagem , Estudos RetrospectivosRESUMO
Smart/intelligent contrast agent candidates for MRI based on Mn(II) ion are rare, as it usually forms labile complexes with polyaminocarboxylate-type ligands. Here, we report the first example of a Mn(II) complex that can be activated by changing the pH of its local environment. The PC2A-EA ligand with an ethylamine pendant arm was found to form a thermodynamically stable (log KMnL = 19.01, pMn = 9.27) and kinetically inert complex with Mn(II) with respect to trans-chelation with a metal ion such as Cu(II). The [MnH(PCA2-EA)] complex displays a relatively slow water exchange rate ((4.0 ± 0.2) × 107 s-1), but the pH-dependent coordination of the ethylamine moiety occurs in the pH range of 6-8 (log KMnLH = 6.88), enabling the complex to exhibit pH-sensitive relaxivity in the biologically relevant pH range.
Assuntos
Meios de Contraste/química , Concentração de Íons de Hidrogênio , Manganês/química , Quelantes/química , Ligantes , Imageamento por Ressonância Magnética/métodosRESUMO
Transparent conductive films are used in a wide variety of devices. While solar cell top electrodes as well as tablet and mobile phone screens require high optical transparency and low sheet resistance (>80% and <10 Ω/â¡) to maximize power efficiency; other, less demanding applications, such as those in capacitive touch panels and antistatic coatings, in which only small currents are involved, can be managed with coatings of moderate conductivity. In this paper, we show that area-selective argon plasma treated polyethylene terephthalate surfaces are suitable for localized deposition of carbon nanotubes from their aqueous dispersions by a simple dip coating and subsequent drying processes. The as-deposited carbon nanotubes form entangled networks in microscopic patterns over the plasma-treated surface areas with sheet resistance of <1 kΩ/â¡ and optical transparency of ~75%. Based on this process, we demonstrate grid-type transparent conductive thin films of carbon nanotubes as capacitive touch sensors. Since each process step is robust, easy to up and downscale, and may be implemented even in roll-to-roll and sheet-to-sheet fabrication, the demonstrated technology is promising to produce grid-type structures even at an industrial scale in the future.
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Pt nanoparticles with controlled size of 1.5 and 6.5 nm were anchored onto the surface of WO3 nanowires (WO3NW) as well as on MCF-17 silica. In the case of WO3NW and MCF-17 supported nanoparticles, 1.5 nm Pt nanoparticles were more active in ethanol decomposition reaction at 533 K. 6.5 nm Pt/WO3NW catalyst showed ~6 times higher activity compared to MCF-17 supported 6.5 nm Pt nanoparticles. While MCF-17 supported catalysts produced hydrogen, methane, carbon-monoxide and acetaldehyde, the tungsten-oxide supported Pt nanoparticles produced a huge amount of acetone as well as ethene with a high acetaldehyde selectivity besides H2, CH4 and CO. The hydrogen formation was significantly higher when the Pt size was 1.5 nm. The metallic nanoparticles, the acid sites and the oxidized centers of support play important role in the formation of decomposition products of ethanol.
RESUMO
Controlled size Pt nanoparticles were anchored onto the surface of 3D mesoporous cobalt-oxide support and was tested in CO2 hydrogenation reactions compared to commercial cobalt-oxide supported Pt nanoparticles prepared by the wet impregnation method as well as SBA-15 silica supported nanoparticles. Designed Pt/mesoporous cobalt-oxide catalysts showed the highest activity as well as the highest methane selectivity. Such catalyst was active at 573 K, while other catalysts showed activity >673 K.
RESUMO
In this paper, we study the thermal activation of CO2 on the surface of small Au nanoparticles supported on TiO2 and titanate nanotube. We characterize the catalysts with high resolution transmission electron microscopy (HR-TEM) and total gold content measurement. We performed catalytic test in flow reactors then we investigate the surface of the catalysts during the adsorption and reaction processes by diffuse reflectance infrared spectroscopy (DRIFTS). The size of gold nanoparticles on the surface has been found to have the most important effect on the final activity of the studied catalysts. Significantly higher TOF values were obtained when the size of Au were smaller on both TiO2 and titanate nanotube supports. The size of the Au nanoparticles with the method of their preparation was controlled. The gold adatom promotes the adsorption and scission of CO2, but the nature of the support has got important effect, too. The explored reaction schemes may pave the way towards novel catalytic materials that can solve challenges associated with the activation of CO2 and thus contribute to a greener chemistry related to it.
RESUMO
Optically transparent conducting materials are essential in modern technology. These materials are used as electrodes in displays, photovoltaic cells, and touchscreens; they are also used in energy-conserving windows to reflect the infrared spectrum. The most ubiquitous transparent conducting material is tin-doped indium oxide (ITO), a wide-gap oxide whose conductivity is ascribed to n-type chemical doping. Recently, it has been shown that ionic liquid gating can induce a reversible, nonvolatile metallic phase in initially insulating films of WO3 Here, we use hard X-ray photoelectron spectroscopy and spectroscopic ellipsometry to show that the metallic phase produced by the electrolyte gating does not result from a significant change in the bandgap but rather originates from new in-gap states. These states produce strong absorption below â¼1 eV, outside the visible spectrum, consistent with the formation of a narrow electronic conduction band. Thus WO3 is metallic but remains colorless, unlike other methods to realize tunable electrical conductivity in this material. Core-level photoemission spectra show that the gating reversibly modifies the atomic coordination of W and O atoms without a substantial change of the stoichiometry; we propose a simple model relating these structural changes to the modifications in the electronic structure. Thus we show that ionic liquid gating can tune the conductivity over orders of magnitude while maintaining transparency in the visible range, suggesting the use of ionic liquid gating for many applications.
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Salmonella Infantis (SI) became endemic in Hungary where the PFGE cluster B, characterized by a large multiresistance (MDR) plasmid emerged among broilers leading to an increased occurrence in humans. We hypothesized that this plasmid (pSI54/04) assisted dissemination of SI. Indeed, Nal-Sul-Tet phenotypes carrying pSI54/04 occurred increasingly between 2011 and 2013 among SI isolates from broilers and humans. Characterization of pSI54/04 based on genome sequence data of the MDR strain SI54/04 indicated a size of â¼277 kb and a high sequence similarity with the megaplasmid pESI of SI predominant in Israel. Molecular characterization of 78 representative broiler and human isolates detected the prototype plasmid pSI54/04 and its variants together with novel plasmid associations within the emerging cluster B. To test in vitro and in vivo pathogenicity of pSI54/04 we produced plasmidic transconjugant of the plasmid-free pre-emergent strain SI69/94. This parental strain and its transconjugant have been tested on chicken embryo fibroblasts (CEFs) and in orally infected day old chicks. The uptake of pSI54/04 did not increase the pathogenicity of the strain SI69/94 in these systems. Thus, dissemination of SI in poultry could be assisted by antimicrobial resistance rather than by virulence modules of the endemic plasmid pSI54/04 in Hungary.
Assuntos
Plasmídeos/genética , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/microbiologia , Infecções por Salmonella/microbiologia , Salmonella enterica/genética , Salmonella enterica/isolamento & purificação , Animais , Antibacterianos/farmacologia , Galinhas , Farmacorresistência Bacteriana Múltipla , Humanos , Hungria/epidemiologia , Epidemiologia Molecular , Plasmídeos/metabolismo , Doenças das Aves Domésticas/epidemiologia , Infecções por Salmonella/epidemiologia , Salmonelose Animal/epidemiologia , Salmonella enterica/classificação , Salmonella enterica/efeitos dos fármacosRESUMO
The survival of children treated with Ewing sarcoma at Semmelweis University were investigated. Pediatric patients with Ewing sarcoma treated at Semmelweis University from 2001 through 2013 were analyzed in terms of overall survival and clinical factors (age, primary localization and extent of the tumor, time interval from primary complaints to diagnosis). For statistical analysis Kaplan-Meier estimated survival and log rank test were applied. Mean age and follow-up time of the 78 patients were 11.16 and 6.29 years, respectively. In 57% of patients time interval from primary symptoms to diagnosis was less than half year. In 53.8% of the patients the disease was metastatic at primary diagnosis (pulmonary only: 29.5%, any other: 24.3%). 5- and 10-year overall survival of patients were 68.1% and 60.4%, respectively. Among the analyzed factors, the presence of metastasis impaired 5-year overall survival significantly (88.5% for localized disease, 63.5% for pulmonary only and 40.9% for any other metastasis). The survival rate of pediatric patients with Ewing sarcoma treated at Semmelweis University is similar to the result in Western European countries.
Assuntos
Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/terapia , Sarcoma de Ewing/mortalidade , Sarcoma de Ewing/terapia , Adolescente , Fatores Etários , Neoplasias Ósseas/patologia , Criança , Pré-Escolar , Estudos de Coortes , Terapia Combinada , Intervalo Livre de Doença , Feminino , Hospitais Universitários , Humanos , Hungria , Estimativa de Kaplan-Meier , Masculino , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Medição de Risco , Sarcoma de Ewing/patologia , Fatores Sexuais , Análise de SobrevidaRESUMO
The genomic island SGI1 and its variants, the important vehicles of multi-resistance in Salmonella strains, are integrative elements mobilized exclusively by the conjugative IncA/C plasmids. Integration and excision of the island are carried out by the SGI1-encoded site-specific recombinase Int and the recombination directionality factor Xis. Chromosomal integration ensures the stable maintenance and vertical transmission of SGI1, while excision is the initial step of horizontal transfer, followed by conjugation and integration into the recipient. We report here that SGI1 not only exploits the conjugal apparatus of the IncA/C plasmids but also utilizes the regulatory mechanisms of the conjugation system for the exact timing and activation of excision to ensure efficient horizontal transfer. This study demonstrates that the FlhDC-family activator AcaCD, which regulates the conjugation machinery of the IncA/C plasmids, serves as a signal of helper entry through binding to SGI1 xis promoter and activating SGI1 excision. Promoters of int and xis genes have been identified and the binding site of the activator has been located by footprinting and deletion analyses. We prove that expression of xis is activator-dependent while int is constitutively expressed, and this regulatory mechanism is presumably responsible for the efficient transfer and stable maintenance of SGI1.
Assuntos
Conjugação Genética , Ilhas Genômicas , Plasmídeos/genética , Salmonella/genética , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Proteínas de Ligação a DNA/metabolismo , Genes Bacterianos , Regiões Promotoras Genéticas , Transativadores/metabolismoRESUMO
According to the statistical data of tumor registries the incidence of cancer has increased in the last decade, however the mortality shows only a slight change due to the new and effective multimodal treatments. The aim of our overview article is to present the changes in the survival of the metastatic patients, and to demonstrate which factors influence their prognosis. The improvement of survival resulted in a more active surgical role both in metastases of the bone of the extremities and the pelvis. We present a diagnostic flow chart and current options for the reconstruction of the different regions of the bone and skeleton, and we will discuss their potential advantages, disadvantages and complications. It is evident that apart from the impending and pathological fracture surgery it is not the first choice of treatment but rather a palliative measure. The aim of surgery is to alleviate pain, to regain mobility and improve quality of life. If possible minimal invasive techniques are performed, as they are less demanding and allow fast rehabilitation for the patient, and they are solutions that last for a lifetime. In optimal conditions radical curative surgery can be performed in about 10 to 15 per cent of the cases, and better survival is encouraging. Orv Hetil. 2017; 158(40): 1563-1569.
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Neoplasias Ósseas/cirurgia , Fraturas Espontâneas/prevenção & controle , Neoplasias Ósseas/complicações , Neoplasias Ósseas/secundário , Progressão da Doença , Fraturas Espontâneas/etiologia , Humanos , Procedimentos Ortopédicos/métodos , PrognósticoRESUMO
Our aim was to investigate the rare malignant soft tissue sarcomas responsible for 1.5% of all malignant tumors, to compare our epidemiological data from the patient population of the Department of Orthopaedics, Semmelweis University, to data described in the international literature for soft tissue tumors. We reviewed 595 cases of primary soft tissue sarcomas treated between 1994 and 2014 and compared results to international data from the literature. Our results were similar to those found in the international literature: mean age, mild male predominance, the most common sarcoma subgroups, the superficial and deep sarcoma ratio, low and high grade sarcoma ratio, the ratio of patients with a primary lung metastasis. Compared to other European data we found significantly longer patient referral to centers (3.6 months in case of superficial sarcomas, 8 months in case of deep localization) which surprisingly had no substantial effect on average tumor size (superficial: 5 cm, deep: 10.5 cm). This corresponds with data from the literature. The long delay period in patients' request of medical service draws attention to difficulties in differential diagnosis in this rare type of tumor, delays in referring patients to a center, and the lack of consultation. We recommend that the required investigations be performed in a musculoskeletal oncology center where this type of cancer is treated.
Assuntos
Diagnóstico Tardio/estatística & dados numéricos , Sistema de Registros , Sarcoma/epidemiologia , Sarcoma/patologia , Neoplasias de Tecidos Moles/epidemiologia , Neoplasias de Tecidos Moles/patologia , Centros Médicos Acadêmicos , Adulto , Distribuição por Idade , Idoso , Causas de Morte , Intervalo Livre de Doença , Feminino , Hospitais Universitários , Humanos , Hungria , Masculino , Pessoa de Meia-Idade , Ortopedia , Prognóstico , Estudos Retrospectivos , Medição de Risco , Sarcoma/terapia , Distribuição por Sexo , Neoplasias de Tecidos Moles/terapia , Análise de Sobrevida , Reino UnidoRESUMO
Two A/C incompatibility group (IncA/C family) plasmids from the 1960s have been sequenced and classified into the A/C2 type 1 group. R16a and IP40a contain novel antibiotic resistance islands and a complete GIsul2 genomic island not previously found in the family. In the 173.1-kb R16a, the 29.9-kb antibiotic resistance island (ARI) is located in a unique backbone position not utilized by ARIs. ARIR16a consists of Tn1, Tn6020, and Tn6333, harboring the resistance genes blaTEM-1D and aphA1b and a mer module, respectively; a truncated Tn5393 copy; and a gene cluster with unknown function. Plasmid IP40a is 170.4 kb in size and contains a 5.6-kb ARI inserted into the kfrA gene. ARIIP40a carrying blaTEM-1D and aphA1b genes is composed of Tn1 with a Tn6023 insertion. Additionally, IP40a harbors single IS2, IS186, and Tn1000 insertions scattered in the backbone; an IS150 copy in GIsul2; and a complete Tn6333 carrying a mer module at the position of ARIR16a Loss of resistance markers in R16a, IP40a, and R55 was observed during stability tests. Every phenotypic change proved to be the result of recombination events involving mobile elements. Intramolecular transposition of IS copies that generated IP40a derivatives lacking large parts of the backbone could account for the formation of other family members, too. The MinION platform proved to be a valuable tool in bacterial genome sequencing since it generates long reads that span repetitive elements and facilitates full-length plasmid or chromosome assembly. Nanopore technology enables rapid characterization of large, low-copy-number plasmids and their rearrangement products.
Assuntos
DNA Bacteriano/genética , Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli/genética , Genoma Bacteriano , Plasmídeos/química , Plasmídeos/história , beta-Lactamases/genética , Antibacterianos/farmacologia , Automação Laboratorial , Conjugação Genética , Elementos de DNA Transponíveis , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Ilhas Genômicas , História do Século XX , Plasmídeos/metabolismo , Análise de Sequência de DNARESUMO
The effects of reduction by H2 and by heat treatment in vacuum and in O2 flow on Rh particle size changes of Rh/CeO2 samples were studied by X-ray photoelectron spectroscopy (XPS), high-resolution electron microscopy (HRTEM), and CO adsorption followed by diffuse reflectance infrared spectroscopy (DRIFTS). Low-temperature (373-423 K) reduction of Rh without agglomeration is demonstrated. An average particle size of 2.3 ± 1.1 nm was measured by HRTEM regardless of the metal loading (1-5%). On Rh/CeO2, a significant particle size increase of the Rh particles was detected on heating (773 K). In this work, we suggest that the temperature-induced surface decrease resulting from the sintering of Rh is favored only for well-dispersed particles. XP spectra revealed that the mobile oxygens of CeO2 fundamentally determine the oxidation state of the supported metals. At elevated temperature, the oxidation of the reduced support surface as well as the metal component takes place because of the segregation of ceria oxygens. When the aggregated particles were reoxidized, the redispersion of Rh was observed probably because of the formation of Rh-O-Ce bonds.
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The incidence of bone tumors is low therefore it is highly recommended to treat patients in specialized centers. In the late 70ies a bone tumor registry was initiated at the Department of Orthopedics of the Semmelweis University followed by the development of a specialized diagnostic unit and a bone cancer center. Several novel surgical procedures have been introduced, including the extremity-sparing surgery, leading to a significant improvement of the patients survival. This is fully supported by a specialized bone cancer oncoteam of experts. The 6000-sized registry and biobank now allows the development of translational research in this orphan tumor type.
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Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/terapia , Salvamento de Membro , Bancos de Espécimes Biológicos , Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/patologia , Neoplasias Ósseas/secundário , Neoplasias Ósseas/cirurgia , Institutos de Câncer , Humanos , Hungria , Tratamentos com Preservação do Órgão , Sistema de Registros , Faculdades de Medicina , Taxa de Sobrevida , Tomografia Computadorizada por Raios X , Resultado do TratamentoRESUMO
Soft tissue sarcomas are rare, reaching some 1.5% of all malignant tumors. While formerly the surgical management of sarcomas almost exclusively consisted of amputation, in the recent years limb saving surgery has become the first choice of therapy. Negative factors affecting the survival rate are: histologically high-grade tumor, size and localization of the tumor, vascular invasion, extensive tumor necrosis, certain subgroups, local recurrence and oncologically positive surgical margin at the resection. Many modern reconstruction possibilities are essential for the safe limb saving surgery with wide surgical margins, such as bone allograft implantation, tumor endoprostheses reconstruction, vascular grafting and plastic surgery. There should always be an attempt to perform limb saving surgery, however life quality, life expectancy and survival are more important considerations influencing essentially the surgical method of choice. In our follow-up study no significant difference in recurrence rate was found between the group of patients with sarcomas requiring a complex reconstruction procedure and the group of those treated by only resection methods (32% versus 47%).