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1.
Sensors (Basel) ; 23(8)2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37112415

RESUMO

An exponential number of devices connect to Internet of Things (IoT) networks every year, increasing the available targets for attackers. Protecting such networks and devices against cyberattacks is still a major concern. A proposed solution to increase trust in IoT devices and networks is remote attestation. Remote attestation establishes two categories of devices, verifiers and provers. Provers must send an attestation to verifiers when requested or at regular intervals to maintain trust by proving their integrity. Remote attestation solutions exist within three categories: software, hardware and hybrid attestation. However, these solutions usually have limited use-cases. For instance, hardware mechanisms should be used but cannot be used alone, and software protocols are usually efficient in particular contexts, such as small networks or mobile networks. More recently, frameworks such as CRAFT have been proposed. Such frameworks enable the use of any attestation protocol within any network. However, as these frameworks are still recent, there is still considerable room for improvement. In this paper, we improve CRAFT's flexibility and security by proposing ASMP (adaptative simultaneous multi-protocol) features. These features fully enable the use of multiple remote attestation protocols for any devices. They also enable devices to seamlessly switch protocols at any time depending on factors such as the environment, context, and neighboring devices. A comprehensive evaluation of these features in a real-world scenario and use-cases demonstrates that they improve CRAFT's flexibility and security with minimal impact on performance.

2.
Case Rep Orthop ; 2019: 9262190, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31583151

RESUMO

Chondroblastoma is a rare benign tumor that affects the epiphysis of long bones in adolescents. Chondroblastoma located in the femoral head is associated with a higher recurrence rate and carries the additional risks of head collapse and degenerative hip disease. Aggressive curettage followed by bone grafting is the current mainstay of treatment. To our knowledge, the long-term postoperative outcome of this technique remains unknown due to the short follow-up of previous case reports. We present the case of a 17-year-old male who underwent fresh osteochondral allograft following curettage of a femoral head chondroblastoma, using a Ganz surgical hip dislocation. He made an uneventful recovery without tumor recurrence. The patient was followed up to 8 years postoperatively. However, there were clinical and radiographic degenerative changes at 6 years of follow-up.

3.
Anticancer Res ; 33(4): 1765-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23564831

RESUMO

AIM: Oxaliplatin with 5-fluorouracil (5-FU) and leucovorin (FOLFOX and FLOX) or capecitabine (XELOX) is the standard adjuvant treatment for colonic cancer. In metastatic disease, 5-FU/leucovorin/irinotecan (FOLFIRI) and FOLFOX are equivalent in respect to response rates, progression-free and overall survival. Little data are available to compare their efficacy after exposure to oxaliplatin-containing adjuvant chemotherapy. PATIENTS AND METHODS: We carried out a retrospective study of patients who underwent surgery and FOLFOX adjuvant chemotherapy, followed by FOLFIRI or FOLFOX for metastatic disease. Exclusion criteria were: metastatic disease at presentation and no oxaliplatin in adjuvant chemotherapy. The end-point was the overall response rate (ORR) to first-line chemotherapy for metastatic disease after three months, as assessed by computed tomography (CT). RESULTS: A total of 205 patients received FOLFOX as adjuvant treatment for colorectal adenocarcinoma between 2006 and 2010. Metastatic disease was diagnosed later in 32 cases after a median follow-up of three years (range=1-5.5 years). The median time between the beginning of adjuvant chemotherapy and onset of metastatic disease was 1.7 years (range=0.5-5.5 years). Twenty-eight patients were evaluable for effects of treatment: six patients received FOLFOX plus bevacizumab and 22 FOLFIRI plus bevacizumab. The ORR was 17% in the FOLFOX group versus 36% in the FOLFIRI group (p=0.22). This difference was not statistically significant, despite a trend in favor of FOLFIRI. CONCLUSION: Metastatic disease after exposure to oxaliplatin in the adjuvant setting tends to occur early and can be characterized by partial resistance to this agent. Despite insufficient statistical power, our results suggest that FOLFIRI may result in higher response rates than FOLFOX in this situation. However, oxaliplatin re-challenge can also lead to radiological responses and disease stabilization.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Anticorpos Monoclonais Humanizados/administração & dosagem , Bevacizumab , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Quimioterapia Adjuvante , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Irinotecano , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
4.
J Colloid Interface Sci ; 377(1): 122-30, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-22487235

RESUMO

We report the synthesis of a new series of Ketal Nucleoside Lipids (KNLs) featuring saturated hydrophobic double chains and either adenosine or uridine as nucleosides (KNL(A) and KNL(U), respectively). Physicochemical studies (differential scanning calorimetry, small angle X ray scattering, transmission electronic microscopy, atomic force microscopy, Langmuir isotherm, infrared spectroscopy) show that the KNLs form hydrogels below the main phase transition temperature (Tm), whereas fluid lamellar phases are obtained above T(m). Mixing complementary KNLs affords a new stable Combined Supramolecular Systems (CSSs) due to complementary A-U recognition. Molecular modeling calculations of the bilayers in a fluid state exhibit a merging of the bilayers partially due to base-base interactions.


Assuntos
Lipídeos/síntese química , Nucleosídeos/síntese química , Lipídeos/química , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/química , Modelos Moleculares , Estrutura Molecular , Nucleosídeos/química , Tamanho da Partícula , Propriedades de Superfície
5.
Ann Surg Oncol ; 19(4): 1081-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22052112

RESUMO

BACKGROUND: Objectives of this study were to evaluate oncologic outcomes and to provide guidelines for the management of primary myxoid (MLS) and round cell liposarcoma (RCLS). METHODS: A multicenter, retrospective study of 418 cases of MRCLS primarily managed by Canadian multidisciplinary sarcoma teams. RESULTS: Study included 418 cases (MLS: 311 patients and RCLS: 107; >5% round cell) with a median age of 45 years and a median follow-up of 5.2 years. Median tumor size was 10 cm, and 81% were deep and 90% were in lower limb. The majority of patients underwent surgical resection and radiotherapy, with a small percentage (6%) receiving chemotherapy. The overall 10-year local control rate was 93% with no differences between MLS and RCLS. Radiotherapy was significant in preventing local relapse and reducing tumor diameter (median=18%) and improving microscopic margin status, but did not impact survival. Radiotherapy and the margin status were independent predictors of local recurrence. The 5- and 10-year metastatic-free survivals were 84 and 77% respectively for MLS and 69 and 46% for RCLS. The initial site of metastasis was found in multiple locations (34%) and bone involvement was frequent (40%) with predilection for spine (79%). Round cell percent (>5%) and tumor diameter (>10 cm) correlated with increased risk for metastasis and death. CONCLUSIONS: MLS and RCLS showed different metastatic risk but equally good local control. Radiotherapy was effective in preventing local recurrence and should be delivered as neoadjuvant. New staging strategies are to be defined to account for the unusual metastatic pattern.


Assuntos
Lipossarcoma Mixoide/radioterapia , Lipossarcoma Mixoide/cirurgia , Recidiva Local de Neoplasia/prevenção & controle , Neoplasias de Tecidos Moles/radioterapia , Neoplasias de Tecidos Moles/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Incidência , Perna (Membro) , Lipossarcoma Mixoide/tratamento farmacológico , Lipossarcoma Mixoide/patologia , Lipossarcoma Mixoide/secundário , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Estudos Retrospectivos , Neoplasias de Tecidos Moles/tratamento farmacológico , Neoplasias de Tecidos Moles/patologia , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
6.
Chem Commun (Camb) ; 46(9): 1464-6, 2010 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-20162149

RESUMO

The present study reports on the formation of supramolecular fibers from a novel cyclen-based ligand and metal salts. In particular, the fibers were shown to stabilize supramolecular porous materials of low density. It was also demonstrated that these fibers could be functionalized by radical polymer growth on their surface. Such new supramolecular fibers constitute a simple and tunable starting material for the synthesis of 1D core-shell objects.


Assuntos
Nanofibras/química , Ciclamos , Compostos Heterocíclicos/química , Ligantes , Metais/química , Metacrilatos/química , Nanofibras/ultraestrutura , Porosidade
8.
Chem Commun (Camb) ; (15): 1661-3, 2006 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-16583012

RESUMO

Hollow microspheres featuring a hybrid lipid-cation multilamellar shell are prepared by hydration of a nucleoside based amphiphile with an aqueous solution containing either actinide or lanthanide salts. The physico-chemical data collected clearly indicate that the formation of these microspheres is a consequence of the following concomitant stabilizing factors: (i) hydrophobic interactions, (ii) nucleobase dimer formation and (iii) phosphate/f-block element salt binding.


Assuntos
Elementos da Série Actinoide/química , Elementos da Série dos Lantanídeos/química , Microesferas , Nucleosídeos/química , Tensoativos/química , Dimerização , Sais , Soluções
9.
Bioconjug Chem ; 17(2): 466-72, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16536479

RESUMO

A novel uridine-based nucleo-lipid, DOTAU (N-[5'-(2',3'-dioleoyl)uridine]-N',N',N'-trimethylammonium tosylate) was prepared by using a convenient four-step synthetic pathway. From the preliminary physicochemical studies (quasielastic light scattering and light microscopy), this amphiphilic structure forms supramolecular organizations in aqueous solution. In addition, in the presence of nucleic acids, transmission electronic microscopy experiments (TEM) and small angle X-ray scattering (SAXS) reveal the formation of multilamellar structures similar to lipoplexes (cationic liposome-DNA complexes) with cationic lipids. The formation of a complex was confirmed by fluorescence spectroscopic assays involving ethidium bromide. Transfection assays of mammalian cell lines (HeLa and MCF-7) indicate that DOTAU can transfect efficiently an expression vector (pEGFP) encoding GFP. Proliferation assays realized on these cell lines show that DOTAU does not inhibit cell proliferation and is less toxic than the commercial Lipofectamine 2000.


Assuntos
Cátions/química , Técnicas de Transferência de Genes , Lipídeos/química , Nucleosídeos/química , Uridina/análogos & derivados , Linhagem Celular Tumoral , Proliferação de Células , Etídio/metabolismo , Ácidos Graxos Monoinsaturados/química , Corantes Fluorescentes/química , Humanos , Estrutura Molecular , Compostos de Amônio Quaternário/química , Uridina/química
10.
Mol Biosyst ; 1(3): 260-4, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16880990

RESUMO

A new transfection reagent based on nucleoside phosphocholine amphiphile leading to high transfection efficacy and low cytotoxicity is described. TEM, ethidium bromide displacement assays, agarose gel electrophoresis and SAXS studies support the formation of lipoplexes for the transfection of CHO cells.


Assuntos
DNA/genética , Transfecção/métodos , Animais , Células CHO , Cricetinae , DNA/química , DNA/ultraestrutura , Ácidos Graxos Monoinsaturados , Genes Reporter , Indicadores e Reagentes , Microscopia Eletrônica , Fosforilcolina , Plasmídeos , Compostos de Amônio Quaternário , Proteínas Recombinantes/metabolismo , Uridina/análogos & derivados , Difração de Raios X , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
11.
J Am Chem Soc ; 126(24): 7533-9, 2004 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-15198600

RESUMO

A family of new uridine phosphocholine amphiphiles that were prepared using a convenient four-step synthetic route is described. Physicochemical studies (differential scanning calorimetry, small-angle X-ray scattering, UV-vis and circular dichroism spectroscopies, light microscopy, transmission electronic microscopy, and scanning electron microscopy) show that these amphiphiles spontaneously assemble into supramolecular structures including vesicles, fibers, hydrogels, and organogels. In aqueous solution, the amphiphiles possessing saturated alkyl chains self-assemble into DNA-like helical fibers in the crystalline state below T(m) and compact bilayers above the melting temperature (T(m)). The transition from bilayers to fibers is thermally reversible. Above a threshold concentration (>6% w/w), a hydrogel is formed due to an entangled network of the fibers. A therapeutic agent such as DNA can be entrapped within the hydrogel structure. In addition to forming bilayer vesicles and hydrogels in aqueous solution, these nucleoside amphiphiles also form organogels in cyclohexane above T(m). Scanning electron microscopy shows a continuous multilamellar phase in the organogels.


Assuntos
Nucleosídeos/síntese química , Nucleosídeos/metabolismo , Fosforilcolina/síntese química , Fosforilcolina/metabolismo , Tensoativos/síntese química , Tensoativos/metabolismo , Animais , Bovinos , Cicloexanos/química , DNA/química , DNA/metabolismo , Hidrogéis/química , Hidrogéis/metabolismo , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Modelos Moleculares , Estrutura Molecular , Nucleosídeos/química , Fosforilcolina/análogos & derivados , Tensoativos/química , Termodinâmica , Uridina/síntese química , Uridina/metabolismo , Água/química , Difração de Raios X
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