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1.
J Biol Chem ; 300(8): 107545, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38992439

RESUMO

DNA double-strand breaks (DSBs) elicit an elaborate response to signal damage and trigger repair via two major pathways: nonhomologous end-joining (NHEJ), which functions throughout the interphase, and homologous recombination (HR), restricted to S/G2 phases. The DNA damage response relies, on post-translational modifications of nuclear factors to coordinate the mending of breaks. Ubiquitylation of histones and chromatin-associated factors regulates DSB repair and numerous E3 ubiquitin ligases are involved in this process. Despite significant progress, our understanding of ubiquitin-mediated DNA damage response regulation remains incomplete. Here, we have performed a localization screen to identify RING/U-box E3 ligases involved in genome maintenance. Our approach uncovered 7 novel E3 ligases that are recruited to microirradiation stripes, suggesting potential roles in DNA damage signaling and repair. Among these factors, the DELTEX family E3 ligase DTX2 is rapidly mobilized to lesions in a poly ADP-ribosylation-dependent manner. DTX2 is recruited and retained at DSBs via its WWE and DELTEX conserved C-terminal domains. In cells, both domains are required for optimal binding to mono and poly ADP-ribosylated proteins with WWEs playing a prominent role in this process. Supporting its involvement in DSB repair, DTX2 depletion decreases HR efficiency and moderately enhances NHEJ. Furthermore, DTX2 depletion impeded BRCA1 foci formation and increased 53BP1 accumulation at DSBs, suggesting a fine-tuning role for this E3 ligase in repair pathway choice. Finally, DTX2 depletion sensitized cancer cells to X-rays and PARP inhibition and these susceptibilities could be rescued by DTX2 reexpression. Altogether, our work identifies DTX2 as a novel ADP-ribosylation-dependent regulator of HR-mediated DSB repair.


Assuntos
Quebras de DNA de Cadeia Dupla , Ubiquitina-Proteína Ligases , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Humanos , ADP-Ribosilação , Reparo do DNA , Reparo do DNA por Junção de Extremidades , Proteína BRCA1/metabolismo , Proteína BRCA1/genética , Ubiquitinação , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/metabolismo , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/genética
2.
Rev Med Liege ; 79(2): 99-103, 2024 Feb.
Artigo em Francês | MEDLINE | ID: mdl-38356426

RESUMO

Bilateral sagittal split osteotomy (BSSO) is a surgical procedure to treat mandibular malpositions. However, this surgery is associated with a risk of recurrence. Osteosynthesis techniques may be the cause of early recurrences. This study aims to demonstrate the efficiency and stability of osteosynthesis with two bicortical screws placed with a transjugal approach. We included patients who benefited from a BSSO alone, between May 2020 and August 2021. We performed the osteosynthesis using two bicortical screws placed with a transjugal approach. All the patients underwent lateral X-rays before the surgery, one week after and minimum six months after the intervention. These medical images allowed to study the mandibular movements during the intervention and the osteosynthesis stability. Twenty-five patients benefited from a BSSO alone. Patients obtained a satisfactory occlusal result. The results showed good stability of the two fragments, after surgery, during the studied period (average follow up of 8 months). Two bicortical screws osteosynthesis placed with a transjugal approach is a simple, effective and stable method for osteosynthesis in case of BSSO.


Les ostéotomies sagittales bilatérales mandibulaires (OSBM) sont des procédures chirurgicales utilisées pour traiter les malpositions mandibulaires. Toutefois, cette chirurgie présente un risque de récidive. Les techniques d'ostéosynthèse pourraient être la cause de récidives précoces. Cette étude vise à démontrer l'efficacité et la stabilité de l'ostéosynthèse à l'aide de deux vis bicorticales placées par voie transjugale. Nous avons inclus les patients ayant bénéficié d'une OSBM seule, entre mai 2020 et août 2021. Nous avons réalisé les ostéosynthèses à l'aide de deux vis bicorticales placées par voie transjugale. Tous les patients ont réalisé des clichés radiologiques de profil avant l'intervention, une semaine après et minimum six mois après. Ces imageries ont permis d'étudier les mouvements mandibulaires durant l'intervention et la stabilité de l'ostéosynthèse. Vingt-cinq patients ont bénéficié d'une OSBM seule. Les patients ont obtenu un résultat occlusal satisfaisant. Les résultats ont montré une bonne stabilité des deux fragments après la chirurgie durant la période étudiée (en moyenne, recul de 8 mois). En conclusion, l'ostéosynthèse à l'aide de deux vis placées par voie transjugale est une méthode simple, efficace et stable d'ostéosynthèse d'OSBM.


Assuntos
Parafusos Ósseos , Osteotomia Mandibular , Humanos , Mandíbula/cirurgia , Osteotomia/métodos , Cefalometria/métodos
3.
Cell Tissue Res ; 392(3): 745-761, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36795154

RESUMO

Recent studies have reported the presence of adult neurogenesis in the arcuate nucleus periventricular space (pvARH) and in the median eminence (ME), two structures involved in reproductive function. In sheep, a seasonal mammal, decreasing daylight in autumn induces a higher neurogenic activity in these two structures. However, the different types of neural stem and progenitor cells (NSCs/NPCs) that populate the arcuate nucleus and median eminence, as well as their location, have not been evaluated. Here, using semi-automatic image analyzing processes, we identified and quantified the different populations of NSCs/NPCs, showing that, during short days, higher densities of [SOX2 +] cells are found in pvARH and ME. In the pvARH, higher densities of astrocytic and oligodendrocitic progenitors mainly contribute to these variations. The different populations of NSCs/NPCs were mapped according to their position relative to the third ventricle and their proximity to the vasculature. We showed that [SOX2 +] cells extended deeper into the hypothalamic parenchyma during short days. Similarly, [SOX2 +] cells were found further from the vasculature in the pvARH and the ME, at this time of year, indicating the existence of migratory signals. The expression levels of neuregulin transcripts (NRGs), whose proteins are known to stimulate proliferation and adult neurogenesis and to regulate progenitor migration, as well as the expression levels of ERBB mRNAs, cognate receptors for NRGs, were assessed. We showed that mRNA expression changed seasonally in pvARH and ME, suggesting that the ErbB-NRG system is potentially involved in the photoperiodic regulation of neurogenesis in seasonal adult mammals.


Assuntos
Hipotálamo , Fotoperíodo , Feminino , Animais , Ovinos , Estações do Ano , Hipotálamo/metabolismo , Ritmo Circadiano , Mamíferos
4.
Histochem Cell Biol ; 157(5): 581-593, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35118552

RESUMO

Sheep, like most seasonal mammals, exhibit a cyclic adaptive reproductive physiology that allows ewes to give birth to their progeny during the spring when environmental conditions are favorable to their survival. This process relies on the detection of day length (or photoperiod) and is associated with profound changes in cellular plasticity and gene expression in the hypothalamic-pituitary-gonadal axis, mechanisms that are suggested to participate in the seasonal adaptation of neuroendocrine circuits. Recently, pituitary vascular growth has been proposed as a seasonally regulated process in which the vascular endothelial growth factor A (VEGFA), a well-known angiogenic cytokine, is suspected to play a crucial role. However, whether this mechanism is restricted to the pituitary gland or also occurs in the mediobasal hypothalamus (MBH), a crucial contributor to the control of the reproductive function, remains unexplored. Using newly developed image analysis tools, we showed that the arcuate nucleus (ARH) of the MBH exhibits an enhanced vascular density during the long photoperiod or non-breeding season, associated with higher expression of VEGFA. In the median eminence (ME), a structure connecting the MBH to the pituitary gland, higher VEGFA, kinase insert domain receptor (KDR/VEGFR2) and plasmalemma vesicle-associated protein (PLVAP) gene expressions were detected during the long photoperiod. We also found that VEGFA and its receptor, VEGFR2, are expressed by neurons and tanycytes in both the ARH and ME. Altogether, these data show variations in the MBH vasculature according to seasons potentially through a VEGFA-dependent pathway, paving the way for future studies aiming to decipher the role of these changes in the hypothalamic control of seasonal reproduction.


Assuntos
Hipotálamo , Fator A de Crescimento do Endotélio Vascular , Animais , Feminino , Hipotálamo/metabolismo , Mamíferos/metabolismo , Fotoperíodo , Hipófise/metabolismo , Estações do Ano , Ovinos , Fator A de Crescimento do Endotélio Vascular/metabolismo
5.
Inorg Chem ; 61(23): 8823-8833, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35635510

RESUMO

A binary phase with Al4Ir composition has been discovered in the Al-Ir binary system. Single-crystal X-ray diffraction analysis reveals that it crystallizes in the trigonal space group P3c1 with the unit cell parameters a = 12.8802(2) Å and c = 9.8130(2) Å. This structure is derived from the Ni2Al3 structure type. The supercell is due to the ordering of the aluminum atoms, which replace the nickel atoms in the prototype structure. The crystal structure was directly imaged by atomic-scale scanning transmission electron microscopy, and the misalignment of the Al site responsible for the supercell has been clearly evidenced. Its metastable nature has been confirmed by differential thermal analysis measurements. The atomic and electronic structures of Al4Ir have also been investigated by density functional theory. The structural optimization leads to lattice parameters and atomic positions in good agreement with the experimental ones. The compound is metallic, with a minimum in the density of states located more than 1 eV above the Fermi energy. This suggests a metastable system, in agreement with the electron count found much above 18 electrons per Ir atom, deviating from the Hume-Rothery rule and with the presence of occupied antibonding states revealed by the crystal orbital Hamiltonian population analysis. The relative stability of the compound is ensured by the hybridization between sp-Al and d-Ir states within Ir-centered clusters, while covalent-like interactions in-between the clusters are indicated by the analysis of the electron localizability function.

6.
Atmos Environ (1994) ; 284: 1-16, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35775067

RESUMO

It is well known that exposure to ambient O3 can decrease growth in many tree species in the United States (US). Our study reports experimental data from outdoor open-top chamber (OTC) studies that quantify total biomass response changes for seedlings of 16 species native to western and eastern North America, which were exposed to several levels of elevated O3 for one or more years. The primary objective of this study is to establish a reference set of parameters for these seedling exposure-response relationships using a 3-month (92 day) 12-hr W126 O3 metric used by US Environmental Protection Agency and other agencies to assess risk to trees from O3 exposure. We classified the 16 species according to their sensitivity, based on the biomass loss response functions to protect from a 5% biomass loss. The three-month 12-h W126 estimated to result in a 5% biomass loss was 2.5-9.2 ppm-h for sensitive species, 20.8-25.2 ppm-h for intermediate species, and > 28.7 ppm-h for insensitive species. The most sensitive tree species include black cherry, ponderosa pine, quaking aspen, red alder, American sycamore, tulip poplar and winged sumac. These species are ecologically important and widespread across US. The effects of O3 on whole-plant biomass depended on exposure duration and dynamics and on the number of successive years of exposure. These species-specific exposure-response relationships will allow US agencies and other groups to better estimate biomass losses based on ozone exposures in North America and can be used in risk assessment and scenario analyses.

7.
Gen Comp Endocrinol ; 304: 113721, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33493505

RESUMO

Unlike mammals, the role of adipokines and more particularly of chemerin in the regulation of food intake is totally unknown in avian species. Here we investigated the effect of chemerin on the food and water consumption and on the body weight in chicken. We studied the effects on the plasma glucose and insulin concentrations and the hypothalamic neuropeptides and AMPK signaling pathway. Female broiler chickens were intraperitoneally injected, daily for 13 days with either vehicle (saline; n = 25) or chemerin (8 µg/kg; n = 25 and 16 µg/kg; n = 25). Food and water intakes were recorded 24 h after each administration. Overnight fasted animals were sacrificed at day 13 (D13), 24 h after the last injection and hypothalamus and left cerebral hemispheres were collected. Chemerin and its receptors protein levels were determined by western-blot. Gene expression of neuropeptide Y (Npy), agouti-related peptide (Agrp), corticotrophin releasing hormone (Crh), pro-opiomelanocortin (Pomc), cocaine and amphetamine-regulated transcript (Cart) and Taste 1 Receptor Member 1 (Tas1r1) were evaluated by RT-qPCR. In chicken, we found that the protein amount of chemerin, CCRL2 and GPR1 was similar in left cerebral hemisphere and hypothalamus whereas CMKLR1 was higher in hypothalamus. Chemerin administration (8 and 16 µg/kg) decreased both food intake and body weight compared to vehicle without affecting water intake and the size or volume of different brain subdivisions as determined by magnetic resonance imaging. It also increased plasma insulin levels whereas glucose levels were decreased. These data were associated with an increase in Npy and Agrp expressions and a decrease in Crh, Tas1r1 mRNA expression within the hypothalamus. Furthermore, chemerin decreased hypothalamic CMKLR1 protein expression and AMPK activation. Taken together, these results support that chemerin could be a peripheral appetite-regulating signal through modulation of hypothalamic peptides expression in chicken.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Peso Corporal , Quimiocinas/farmacologia , Galinhas , Ingestão de Alimentos , Neuropeptídeos , Animais , Feminino , Expressão Gênica , Hipotálamo/metabolismo , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Pró-Opiomelanocortina/genética , Transdução de Sinais
8.
BMC Fam Pract ; 22(1): 165, 2021 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-34364386

RESUMO

BACKGROUND: About 25% of patients experience adverse drug events (ADE) in primary care, but few events are reported by the patients themselves. One solution to improve the detection and management of ADEs in primary care is for patients to report them to their general practitioner. The study aimed to assess the effect of a booklet designed to improve communication and interaction between patients treated with anti-hypertensive drugs and general practitioners on the reporting of ADEs. METHODS: A cluster randomized controlled cross-sectional stepped wedge open trial (five periods of 3 months) was conducted. A cluster was a group of general practitioners working in ambulatory offices in France. Adults consulting their general practitioner to initiate, modify, or renew an antihypertensive prescription were included. A booklet including information on cardiovascular risks, antihypertensive treatments, and ADE report forms was delivered by the general practitioner to the patient in the intervention group. The primary outcome was the reporting of at least one ADE by the patient to his general practitioner during the three-month period after enrolment. Two clusters were randomised by sequence for a total of 8 to receive the intervention. An intention-to-treat analysis was conducted. A logistic mixed model with random intercept was used. RESULTS: Sixty general practitioners included 1095 patients (median: 14 per general practitioner; range: 1-103). More patients reported at least one ADE to their general practitioner in the intervention condition compared to the control condition (aOR = 3.5, IC95 [1.2-10.1], p = 0.02). The modification and initiation of an antihypertensive treatment were also significantly associated with the reporting of ADEs (aOR = 4.4, CI95 [1.9-10.0], p <  0.001 and aOR = 11.0, CI95 [4.6-26.4], p <  0.001, respectively). The booklet delivery also improved patient satisfaction on general practitioner communication and high blood pressure management. CONCLUSION: A booklet can improve patient self-reporting of ADEs to their general practitioners. Future research should assess whether it can improve general practitioner management of ADEs and patient's health status. TRIAL REGISTRATION: Trial registry identifier NCT01610817 (2012/05/30).


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Clínicos Gerais , Adulto , Anti-Hipertensivos/uso terapêutico , Estudos Transversais , Humanos , Atenção Primária à Saúde
9.
Inorg Chem ; 59(1): 360-366, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31859489

RESUMO

A new ternary phase with a composition Al1+xV2Sn2-x (x = 0.19) has been found during investigation of the Al-V-Sn ternary system. Single-crystal X-ray diffraction measurements reveal that this ternary phase crystallizes with an orthorhombic structure with a = 5.5931(1) Å, b = 18.8017(5) Å, and c = 6.7005(2) Å (space group Cmce). This compound is thus isostructural to the GaV2Sn2 structure type, showing a layered structure composed of vanadium cluster bands formed with pentagonal faces intercalated by Sn atom layers. High-resolution transmission electron microscopy measurements confirm the orthorhombic structure. Regarding lattice perfection, no dislocation could be identified within the probed Al1.19V2Sn1.81 single-crystal lamella. Ab initio calculations reveal a reduction of the density of states at the Fermi level, which could be attributed to both a Hume-Rothery effect combined with strong spd hybridization.

10.
Nucleic Acids Res ; 45(15): 8859-8872, 2017 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-28666352

RESUMO

RPA-coated single-stranded DNA (RPA-ssDNA), a nucleoprotein structure induced by DNA damage, promotes ATR activation and homologous recombination (HR). RPA is hyper-phosphorylated and ubiquitylated after DNA damage. The ubiquitylation of RPA by PRP19 and RFWD3 facilitates ATR activation and HR, but how it is stimulated by DNA damage is still unclear. Here, we show that RFWD3 binds RPA constitutively, whereas PRP19 recognizes RPA after DNA damage. The recruitment of PRP19 by RPA depends on PIKK-mediated RPA phosphorylation and a positively charged pocket in PRP19. An RPA32 mutant lacking phosphorylation sites fails to recruit PRP19 and support RPA ubiquitylation. PRP19 mutants unable to bind RPA or lacking ubiquitin ligase activity also fail to support RPA ubiquitylation and HR. These results suggest that RPA phosphorylation enhances the recruitment of PRP19 to RPA-ssDNA and stimulates RPA ubiquitylation through a process requiring both PRP19 and RFWD3, thereby triggering a phosphorylation-ubiquitylation circuitry that promotes ATR activation and HR.


Assuntos
Enzimas Reparadoras do DNA/genética , Reparo do DNA , DNA de Cadeia Simples/genética , Recombinação Homóloga , Proteínas Nucleares/genética , Fatores de Processamento de RNA/genética , Proteína de Replicação A/genética , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Linhagem Celular Tumoral , Dano ao DNA , Enzimas Reparadoras do DNA/química , Enzimas Reparadoras do DNA/metabolismo , Replicação do DNA , DNA de Cadeia Simples/metabolismo , Regulação da Expressão Gênica , Células HEK293 , Células HeLa , Humanos , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Fosforilação , Fatores de Processamento de RNA/química , Fatores de Processamento de RNA/metabolismo , Proteína de Replicação A/metabolismo , Transdução de Sinais , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
11.
Chem Soc Rev ; 47(20): 7703-7738, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30211916

RESUMO

Methyl methacrylate (MMA) is a specialty monomer for poly methyl methacrylate (PMMA) and the increasing demand for this monomer has motivated industry to develop clean technologies based on renewable resources. The dominant commercial process reacts acetone and hydrogen cyanide to MMA (ACH route) but the intermediates (hydrogen cyanide, and acetone cyanohydrin) are toxic and represent an environmental hazard. Esterification of methacrylic acid (MAA) to MMA is a compelling alternative together with ethylene, propylene, and isobutene/t-butanol as feedstocks. Partially oxidizing isobutane or 2-methyl-1,3-propanediol (2MPDO) over heteropolycompounds to MAA in a single-step is nascent technology to replace current processes. The focus of this review is on catalysts and their role in the development of processes herein described. Indeed, in some cases remarkable catalysts were studied that enabled considerable steps forward in both the advancement of catalysis science and establishing the basis for new technologies. An emblematic example is represented by Keggin-type heteropolycompounds with cesium and vanadium, which are promising catalysts to convert isobutane and 2MPDO to MAA. Renewable sources for the MMA or MAA route include acetone, isobutanol, ethanol, lactic, itaconic, and citric acids. End-of-life PMMA is expected to grow as a future source of MMA.

12.
Molecules ; 24(12)2019 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-31234486

RESUMO

A number of salophen ligands and their Zn, Ni, and Pd complexes were synthesized by an efficient one-pot mechanosynthesis protocol. The reaction products were characterized by means of complementary solid-state techniques, i.e., powder X-ray diffraction, single-crystal X-ray diffraction, and solid-state NMR spectroscopy. Four new crystal structures of metal salophen complexes as DMSO solvates are here reported. The described simple and relatively fast (about 1 h for all derivatives) procedure is a good alternative to classical methods performed in organic solvents.


Assuntos
Complexos de Coordenação/química , Níquel/química , Paládio/química , Salicilatos/química , Zinco/química , Fenômenos Químicos , Complexos de Coordenação/síntese química , Ligantes , Fenômenos Mecânicos , Modelos Moleculares , Estrutura Molecular , Análise Espectral
13.
Sci Technol Adv Mater ; 17(1): 71-79, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27877859

RESUMO

After gas atomization, a quasicrystalline powder based on aluminium was used to prepare a thick coating by high-velocity oxygen-fuel flame torch spraying. This layer was deposited on top of a bond-coat layer on a steel plate. A post-spraying annealing treatment turned the two layers to their stable state, a γ-brass crystal and an icosahedral quasicrystal, respectively. The projection parameters were selected in such a way that the coating behaved like a self-lubricating material, which offered very good wear resistance (duration of pin-on-disk tests superior to 5 km with negligible material loss) and low friction (µ ≤ 6% against sintered tungsten carbide), in contrast to the state of the art. This property was achieved thanks to, on the one hand, excellent bonding to the substrate via the bound coat, and on the other hand, presence at the boundaries between quasicrystalline flakes of a mixture of both threefold and fourfold coordinated carbon originating from spray processing. Application to hard materials used in mechanical devices is appealing, especially because soft, lubricating additives may not be needed, thus considerably increasing the lifetime of the devices and reducing waste of materials.

14.
Lancet Oncol ; 16(1): 47-56, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25500422

RESUMO

BACKGROUND: Since the introduction of breast-conserving treatment, various radiation doses after lumpectomy have been used. In a phase 3 randomised controlled trial, we investigated the effect of a radiation boost of 16 Gy on overall survival, local control, and fibrosis for patients with stage I and II breast cancer who underwent breast-conserving treatment compared with patients who received no boost. Here, we present the 20-year follow-up results. METHODS: Patients with microscopically complete excision for invasive disease followed by whole-breast irradiation of 50 Gy in 5 weeks were centrally randomised (1:1) with a minimisation algorithm to receive 16 Gy boost or no boost, with minimisation for age, menopausal status, presence of extensive ductal carcinoma in situ, clinical tumour size, nodal status, and institution. Neither patients nor investigators were masked to treatment allocation. The primary endpoint was overall survival in the intention-to-treat population. The trial is registered with ClinicalTrials.gov, number NCT02295033. FINDINGS: Between May 24, 1989, and June 25, 1996, 2657 patients were randomly assigned to receive no radiation boost and 2661 patients randomly assigned to receive a radiation boost. Median follow-up was 17.2 years (IQR 13.0-19.0). 20-year overall survival was 59.7% (99% CI 56.3-63.0) in the boost group versus 61.1% (57.6-64.3) in the no boost group, hazard ratio (HR) 1.05 (99% CI 0.92-1.19, p=0.323). Ipsilateral breast tumour recurrence was the first treatment failure for 354 patients (13%) in the no boost group versus 237 patients (9%) in the boost group, HR 0.65 (99% CI 0.52-0.81, p<0.0001). The 20-year cumulative incidence of ipsilatelal breast tumour recurrence was 16.4% (99% CI 14.1-18.8) in the no boost group versus 12.0% (9.8-14.4) in the boost group. Mastectomies as first salvage treatment for ipsilateral breast tumour recurrence occurred in 279 (79%) of 354 patients in the no boost group versus 178 (75%) of 237 in the boost group. The cumulative incidence of severe fibrosis at 20 years was 1.8% (99% CI 1.1-2.5) in the no boost group versus 5.2% (99% CI 3.9-6.4) in the boost group (p<0.0001). INTERPRETATION: A radiation boost after whole-breast irradiation has no effect on long-term overall survival, but can improve local control, with the largest absolute benefit in young patients, although it increases the risk of moderate to severe fibrosis. The extra radiation dose can be avoided in most patients older than age 60 years. FUNDING: Fonds Cancer, Belgium.


Assuntos
Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Mastectomia Segmentar , Dosagem Radioterapêutica , Adulto , Fatores Etários , Austrália , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Europa (Continente) , Feminino , Fibrose , Humanos , Análise de Intenção de Tratamento , Israel , Estimativa de Kaplan-Meier , Mastectomia , Mastectomia Segmentar/efeitos adversos , Mastectomia Segmentar/mortalidade , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Seleção de Pacientes , Modelos de Riscos Proporcionais , Radioterapia Adjuvante , Reoperação , Terapia de Salvação , Fatores de Tempo , Resultado do Tratamento
15.
Sci Technol Adv Mater ; 15(3): 034804, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27877675

RESUMO

The discovery in 1987 of stable quasicrystals in the Al-Cu-Fe system was soon exploited to patent specific coatings that showed reduced friction in ambient air against hard antagonists. Henceforth, it was possible to develop a number of applications, potential or commercially exploited to date, that will be alluded to in this topical review. A deeper understanding of the characteristics of complex metallic alloys (CMAs) may explain why material made of metals like Al, Cu and Fe offers reduced friction; low solid-solid adhesion came later. It is linked to the surface energy being significantly lower on those materials, in which translational symmetry has become a weak property, that is determined by the depth of the pseudo-gap at the Fermi energy. As a result, friction is anisotropic in CMAs that builds up according to the translation symmetry along one direction, but is aperiodic along the other two directions. A review is given in this article of the most salient data found along these lines during the past two decades or so.

16.
Sci Technol Adv Mater ; 15(2): 024802, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27877661

RESUMO

Additive manufacturing processes allow freeform fabrication of the physical representation of a three-dimensional computer-aided design (CAD) data model. This area has been expanding rapidly over the last 20 years. It includes several techniques such as selective laser sintering and stereolithography. The range of materials used today is quite restricted while there is a real demand for manufacturing lighter functional parts or parts with improved functional properties. In this article, we summarize recent work performed in this field, introducing new composite materials containing complex metallic alloys. These are mainly Al-based quasicrystalline alloys whose properties differ from those of conventional alloys. The use of these materials allows us to produce light-weight parts consisting of either metal-matrix composites or of polymer-matrix composites with improved properties. Functional parts using these alloys are now commercialized.

17.
ChemSusChem ; 17(5): e202301172, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38216531

RESUMO

Plastic pollution is a generational problem, and stakeholders are turning to chemical recycling as a potential solution. However, decision-makers necessitate quick and reliable capital investment estimations to evaluate innovative technologies, especially in the early project stage, when limited historical data are available. To address this need, we built a database of 160+ chemical recycling plants, querying for nominal capacity, year and place of construction, total capital investment (TCI), number of long-term jobs and opportunity of subsidies. Then, we compared conventional association of the advancement of cost engineering AACE class 5 estimation methods, with literature estimates, and commercial capital expenditure confidence intervals for pyrolysis, gasification, solvolysis, and selective dissolution. We demonstrate the unreliability of classic methods, and we propose ballpark correlations based on the plant capacity, or the energy loss. Chemical recycling plants suffer from poor economy of scale (with current technologies), and capacity is not always the best indicator for TCI estimation. Pyrolysis and gasification are energy-driven technologies, and their TCI correlates very well (R2 =0.91-0.92) with the total energy losses. Solvolysis and selective dissolution, instead, are at an earlier development stage, so cost engineers or researchers will have to accept less certain TCI vs capacity (R2 =0.60).

18.
Sci Data ; 11(1): 1061, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39349475

RESUMO

A Rural Observatory System (ROS) was established in Madagascar to address the lack of socioeconomic data on rural areas. It collected, analyzed, and disseminated data to help formulate and evaluate development policies. From 1995 to 2015, the ROS surveyed a total of 26 areas. The ROS methodology involved annual household panel surveys using consistent questionnaires supplemented by modules covering new themes. Qualitative community surveys were used to understand local features and dynamics. The site selection combined quantitative and qualitative insights to reflect the diversity of Madagascar's rural challenges. Quality control was comprehensive, with measures such as limiting the number of daily surveyor interviews and daily field supervision. By making this data available for 21 consecutive years, along with documentation, metadata, and code with analysis examples, we aim to facilitate their discovery, assessment, and understanding by researchers, policymakers, and social organizations. To our knowledge, this is the only available data for an in-depth analysis of the situation and trends in the rural areas of Madagascar.


Assuntos
Características da Família , População Rural , Madagáscar , Humanos , Inquéritos e Questionários , Estudos Longitudinais , Fatores Socioeconômicos
19.
J Appl Clin Med Phys ; 14(4): 4094, 2013 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-23835376

RESUMO

Concurrent radiotherapy to the pelvis plus a prostate boost with long-term androgen deprivation is a standard of care for locally advanced prostate cancer. IMRT has the ability to deliver highly conformal dose to the target while lowering irradiation of critical organs around the prostate. Volumetric-modulated arc therapy is able to reduce treatment time, but its impact on organ sparing is still controversial when compared to static gantry IMRT. We compared the two techniques in simultaneous integrated boost plans. Ten patients with locally advanced prostate cancer were included. The planning target volume (PTV) 1 was defined as the pelvic lymph nodes, the prostate, and the seminal vesicles plus setup margins. The PTV2 consisted of the prostate with setup margins. The prescribed doses to PTV1 and PTV2 were 54 Gy in 37 fractions and 74 Gy in 37 fractions, respectively. We compared simultaneous integrated boost plans by means of either a seven coplanar static split fields IMRT, or a one-arc (RA1) and a two-arc (RA2) RapidArc planning. All three techniques allowed acceptable homogeneity and PTV coverage. Static IMRT enabled a better homogeneity for PTV2 than RapidArc techniques. Sliding window IMRT and VMAT permitted to maintain doses to OAR within acceptable levels with a low risk of side effects for each organ. VMAT plans resulted in a clinically and statistically significant reduction in doses to bladder (mean dose IMRT: 50.1 ± 4.6Gy vs. mean dose RA2: 47.1 ± 3.9 Gy, p = 0.037), rectum (mean dose IMRT: 44± 4.5 vs. mean dose RA2: 41.6 ± 5.5 Gy, p = 0.006), and small bowel (V30 IMRT: 76.47 ± 14.91% vs. V30 RA2: 47.49 ± 16.91%, p = 0.002). Doses to femoral heads were higher with VMAT but within accepted constraints. Our findings suggest that simultaneous integrated boost plans using VMAT and sliding window IMRT allow good OAR sparing while maintaining PTV coverage within acceptable levels.


Assuntos
Neoplasias da Próstata/radioterapia , Radioterapia de Intensidade Modulada/métodos , Humanos , Masculino , Pelve/efeitos da radiação , Neoplasias da Próstata/diagnóstico por imagem , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/estatística & dados numéricos , Radioterapia de Intensidade Modulada/estatística & dados numéricos , Tomografia Computadorizada por Raios X
20.
Chem Soc Rev ; 41(20): 6760-77, 2012 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-22933085

RESUMO

This article aims at an account of what is known about the potential for applications of quasicrystals and related compounds, the so-called family of Complex Metallic Alloys (CMAs‡). Attention is focused at aluminium-based CMAs, which comprise a large number of crystalline compounds and quasicrystals made of aluminium alloyed with transition metals (like Fe or Cu) or normal metals like Mg. Depending on composition, the structural complexity varies from a few atoms per unit cell up to thousands of atoms. Quasicrystals appear then as CMAs of ultimate complexity and exhibit a lattice that shows no periodicity anymore in the usual 3-dimensional space. Properties change dramatically with lattice complexity and turn the metal-type behaviour of simple Al-based crystals into a far more complex behaviour, with a fingerprint of semi-conductors that may be exploited in various applications, potential or realised. An account of the ones known to the author is given in the light of the relevant properties, namely light absorption, reduced adhesion and friction, heat insulation, reinforcement of composites for mechanical devices, and few more exotic ones. The role played by the search for applications of quasicrystals in the development of the field is briefly addressed in the concluding section.

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