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OBJECTIVE: Ischemic complications account for significant patient morbidity following aneurysmal subarachnoid hemorrhage (aSAH). The Prevention and Treatment of Vasospasm with Clazosentan (REACT) study was designed to assess the safety and efficacy of clazosentan, an endothelin receptor antagonist, in preventing clinical deterioration due to delayed cerebral ischemia (DCI) in patients with aSAH. METHODS: REACT was a prospective, multicenter, randomized, double-blind, phase 3 study. Eligible patients had aSAH secured by surgical clipping or endovascular coiling, and had presented with thick and diffuse clot on admission CT scan. Patients were randomized (1:1 ratio) to 15 mg/hour intravenous clazosentan or placebo within 96 hours of the aSAH for up to 14 days, in addition to standard of care treatment including oral or intravenous nimodipine. The primary efficacy endpoint was the occurrence of clinical deterioration due to DCI up to 14 days after initiation of the study drug. The main secondary endpoint was the occurrence of clinically relevant cerebral infarction at day 16 after study drug initiation. Other secondary endpoints included clinical outcome assessed on the modified Rankin Scale (mRS) and the Glasgow Outcome Scale-Extended (GOSE) at week 12 post-aSAH. Imaging and clinical endpoints were centrally adjudicated. RESULTS: A total of 409 patients were randomized between February 2019 and May 2022 across 74 international sites. Three patients did not start study treatment and were not included in the analysis set. The occurrence of clinical deterioration due to DCI was 15.8% (32/202 patients) in the clazosentan group and 17.2% (35/204 patients) in the placebo group, and the difference was not statistically significant (relative risk reduction [RRR] 7.2%, 95% CI -42.6% to 39.6%, p = 0.734). A nonsignificant RRR of 34.1% (95% CI -21.3% to 64.2%, p = 0.177) was observed in clinically relevant cerebral infarcts treated with clazosentan (7.4%, 15/202) versus placebo (11.3%, 23/204). Rescue therapy was less frequently needed for patients treated with clazosentan compared to placebo (10.4%, 21/202 vs 18.1%, 37/204; RRR 42.6%, 95% CI 5.4%-65.2%). A nonsignificant relative risk increase of 25.4% (95% CI -10.7% to 76.0%, p = 0.198) was reported in the risk of poor GOSE and mRS scores with clazosentan (24.8%, 50/202) versus placebo (20.1%, 41/204) at week 12 post-aSAH. Treatment-emergent adverse events were similar to those reported previously. CONCLUSIONS: Clazosentan administered for up to 14 days at 15 mg/hour had no significant effect on the occurrence of clinical deterioration due to DCI. Clinical trial registration no.: NCT03585270 (ClinicalTrials.gov) EU clinical trial registration no.: 2018-000241-39 (clinicaltrialsregister.eu).
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BACKGROUND: For patients presenting with an aneurysmal subarachnoid hemorrhage (aSAH), delayed cerebral ischemia (DCI) is a significant cause of morbidity and mortality. The REACT study is designed to assess the safety and efficacy of clazosentan in preventing clinical deterioration due to DCI in patients with aSAH. METHODS: REACT is a prospective, multicenter, randomized phase 3 study that is planned to enroll 400 patients with documented aSAH from a ruptured cerebral aneurysm, randomized 1:1 to 15 mg/hour intravenous clazosentan vs. placebo, in approximately 100 sites and 15 countries. Eligible patients are required to present at hospital admission with CT evidence of significant subarachnoid blood, defined as a thick and diffuse clot that is more than 4 mm in thickness and involves 3 or more basal cisterns. The primary efficacy endpoint is the occurrence of clinical deterioration due to DCI up to 14 days post-study drug initiation. The main secondary endpoint is the occurrence of clinically relevant cerebral infarction at Day 16 post-study drug initiation. Other secondary endpoints include the modified Rankin Scale (mRS) and the Glasgow Outcome Scale-Extended (GOSE) score at Week 12 post-aSAH, dichotomized into poor and good outcome. Radiological results and clinical endpoints are centrally evaluated by independent committees, blinded to treatment allocation. Exploratory efficacy endpoints comprise the assessment of cognition status at 12 weeks and quality of life at 12 and 24 weeks post aSAH. DISCUSSION: In the REACT study, clazosentan is evaluated on top of standard of care to determine if it reduces the risk of clinical deterioration due to DCI after aSAH. The selection of patients with thick and diffuse clots is intended to assess the benefit/risk profile of clazosentan in a population at high risk of vasospasm-related ischemic complications post-aSAH. TRIAL REGISTRATION (ADDITIONAL FILE 1): ClinicalTrials.gov (NCT03585270). EU Clinical Trial Register (EudraCT Number: 2018-000241-39).
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Isquemia Encefálica , Deterioração Clínica , Hemorragia Subaracnóidea , Vasoespasmo Intracraniano , Humanos , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/tratamento farmacológico , Estudos Prospectivos , Qualidade de Vida , Vasoespasmo Intracraniano/etiologia , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/etiologia , Isquemia Encefálica/prevenção & controle , Infarto Cerebral/etiologiaRESUMO
Life is thought to have appeared in the depth of the sea under high hydrostatic pressure. Nowadays, it is known that the deep biosphere hosts a myriad of life forms thriving under high-pressure conditions. However, the evolutionary mechanisms leading to their adaptation are still not known. Here, we show the molecular bases of these mechanisms through a joint structural and dynamical study of two orthologous proteins. We observed that pressure adaptation involves the decoupling of protein-water dynamics and the elimination of cavities in the protein core. This is achieved by rearranging the charged residues on the protein surface and using bulkier hydrophobic residues in the core. These findings will be the starting point in the search for a complete genomic model explaining high-pressure adaptation.
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Aclimatação , Adaptação Fisiológica , Pressão HidrostáticaRESUMO
Infectious alleles of endogenous banana streak viruses (eBSVs) are present in the genome of all banana interspecific cultivars, including plantains and cooking types. Activation of these infectious eBSV alleles by biotic and abiotic stresses leads to spontaneous infections by cognate viruses and raises concerns about their ability to promote outbreaks of banana streak viruses under field cultivation conditions. We undertook a comprehensive risk assessment study of infectious eBSV alleles of species BSOLV, BSGFV and BSIMV in banana interspecific cultivars in Guadeloupe, a tropical island of the Caribbean where bananas are grown for export and local markets. We carried out a prevalence survey of BSOLV, BSGFV and BSIMV species in a range of cultivars grown in Guadeloupe. Our results suggest that BSOLV and BSGFV infections arise from the activation of infectious eBSVs rather than vector-borne transmission and point to a correlation between altitude and infection rates in interspecific hybrids with AAB genotypes. We studied the dynamics of activation of infectious eBSOLV and eBSGFV alleles by tissue culture and field cultivation in a range of cultivars. We showed that tissue culture and field cultivation trigger distinct activation pathways, resulting in distinct activation patterns. We also showed that activation decreased over time during cell culture and field cultivation and that BSV infections arising from the activation of infectious eBSV alleles cause symptomless infections in the most cultivated plantain in Guadeloupe, French Clair. Overall, our study shows that the risk of BSV outbreaks resulting from the activation of infectious eBSVs in plantain originating from vegetative multiplication is negligible in Guadeloupe.
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Despite advances in experimental and computational methods, the mechanisms by which an unstructured polypeptide chain regains its unique three-dimensional structure remains one of the main puzzling questions in biology. Single-molecule techniques, ultra-fast perturbation and detection approaches and improvement in all-atom and coarse-grained simulation methods have greatly deepened our understanding of protein folding and the effects of environmental factors on folding landscape. However, a major challenge remains the detailed characterization of the protein folding landscape. Here, we used high hydrostatic pressure 2D NMR spectroscopy to obtain high-resolution experimental structural information in a site-specific manner across the polypeptide sequence and along the folding reaction coordinate. We used this residue-specific information to constrain Cyana3 calculations, in order to obtain a topological description of the entire folding landscape. This approach was used to describe the conformers populating the folding landscape of two small globular proteins, AVR-Pia and AVR-Pib, that belong to the structurally conserved but sequence-unrelated MAX effectors superfamily. Comparing the two folding landscapes, we found that, in spite of their divergent sequences, the folding pathway of these two proteins involves a similar, inescapable, folding intermediate, even if, statistically, the routes used are different.
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Ascomicetos , Dobramento de Proteína , Espectroscopia de Ressonância Magnética , Proteínas/químicaRESUMO
Multidimensional NMR intrinsically provides multiple probes that can be used for deciphering the folding pathways of proteins: NH amide and CαHα groups are strategically located on the backbone of the protein, while CH3 groups, on the side-chain of methylated residues, are involved in important stabilizing interactions in the hydrophobic core. Combined with high hydrostatic pressure, these observables provide a powerful tool to explore the conformational landscapes of proteins. In the present study, we made a comparative assessment of the NH, CαHα, and CH3 groups for analyzing the unfolding pathway of ∆+PHS Staphylococcal Nuclease. These probes yield a similar description of the folding pathway, with virtually identical thermodynamic parameters for the unfolding reaction, despite some notable differences. Thus, if partial unfolding begins at identical pressure for these observables (especially in the case of backbone probes) and concerns similar regions of the molecule, the residues involved in contact losses are not necessarily the same. In addition, an unexpected slight shift toward higher pressure was observed in the sequence of the scenario of unfolding with CαHα when compared to amide groups.
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When combined with NMR spectroscopy, high hydrostatic pressure is an alternative perturbation method used to destabilize globular proteins that has proven to be particularly well suited for exploring the unfolding energy landscape of small single-domain proteins. To date, investigations of the unfolding landscape of all-ß or mixed-α/ß protein scaffolds are well documented, whereas such data are lacking for all-α protein domains. Here we report the NMR study of the unfolding pathways of GIPC1-GH2, a small α-helical bundle domain made of four antiparallel α-helices. High-pressure perturbation was combined with NMR spectroscopy to unravel the unfolding landscape at three different temperatures. The results were compared to those obtained from classical chemical denaturation. Whatever the perturbation used, the loss of secondary and tertiary contacts within the protein scaffold is almost simultaneous. The unfolding transition appeared very cooperative when using high pressure at high temperature, as was the case for chemical denaturation, whereas it was found more progressive at low temperature, suggesting the existence of a complex folding pathway.
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Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Desdobramento de Proteína/efeitos dos fármacos , Humanos , Cinética , Modelos Moleculares , Conformação Proteica/efeitos dos fármacos , Conformação Proteica em alfa-Hélice/fisiologia , Desnaturação Proteica , Domínios Proteicos , Temperatura , TermodinâmicaRESUMO
High-hydrostatic pressure is an alternative perturbation method that can be used to destabilize globular proteins. Generally perfectly reversible, pressure exerts local effects on regions or domains of a protein containing internal voids, contrary to heat or chemical denaturant that destabilize protein structures uniformly. When combined with NMR spectroscopy, high pressure (HP) allows one to monitor at a residue-level resolution the structural transitions occurring upon unfolding and to determine the kinetic properties of the process. The use of HP-NMR has long been hampered by technical difficulties. Owing to the recent development of commercially available high-pressure sample cells, HP-NMR experiments can now be routinely performed. This review summarizes recent advances of HP-NMR techniques for the characterization at a quasi-atomic resolution of the protein folding energy landscape.
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Espectroscopia de Ressonância Magnética , Modelos Moleculares , Pressão , Conformação Proteica , Dobramento de Proteína , Proteínas/química , Pressão Hidrostática , Cinética , Espectroscopia de Ressonância Magnética/métodos , Modelos Teóricos , Desdobramento de Proteína , Relação Estrutura-Atividade , TermodinâmicaRESUMO
BACKGROUND: Infectious complications after pediatric liver transplantation frequently occur and are potentially serious. Data concerning strictly defined bacterial infections and their associated risk factors are lacking. METHODS: For the pediatric liver transplant postoperative period, we analyzed data from the nosocomial infection surveillance (2006-2015). RESULTS: A total of 235 bacterial infections in 162 transplantations (47%) occurred, including 32 bacterial pneumonia cases, 104 surgical site infections, 27 urinary tract infections, and 40 bloodstream infections. Sepsis was diagnosed in 127 cases (54%), severe sepsis in 22 (9%) cases, and septic shock in 41 (17%) cases. Thirty patients (9%) died, and septic shock was the leading cause of death. The carrier status of multi-drug resistant bacteria and a tacrolimus level >20 ng/mL were independent risk factors for surgical site infections and the occurrence of severe sepsis or septic shock. The length of mechanical ventilation was an independent risk factor for pneumonia and surgical site infection. CONCLUSION: Bacterial infections in the early postoperative period after pediatric liver transplantation are associated with high morbidity and mortality. Physicians involved in the medical care of these patients should be aware of the specific risk factors, and further development of prevention programs is highly recommended.
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Infecções Bacterianas/etiologia , Transplante de Fígado/efeitos adversos , Infecções Bacterianas/mortalidade , Criança , Pré-Escolar , Monitoramento Epidemiológico , Feminino , Humanos , Imunossupressores/administração & dosagem , Masculino , Análise Multivariada , Pneumonia/etiologia , Pneumonia/microbiologia , Fatores de Risco , Sepse/etiologia , Sepse/microbiologia , Infecções Urinárias/etiologia , Infecções Urinárias/microbiologiaRESUMO
OBJECTIVES: The existence of a relationship between hospital surgical volume and outcome after lung cancer surgery remains an ongoing debate. We aimed to evaluate the association between volume and 60-day mortality, 1- and 3-year observed survival (OS) in non-small cell lung cancer (NSCLC) patients in Belgium. METHODS: Patients diagnosed with NSCLC in 2010-2011 were identified in the database of the Belgian Cancer Registry, excluding patients with multiple tumours. Regression models were applied to assess the relationship between hospital surgical volume, 60-day mortality and 1- and 3-year OS, adjusting for different patient and tumour characteristics. Surgical volume was taken into account as a continuous variable in the models. RESULTS: In 2010-2011 a total of 9,817 patients with NSCLC were diagnosed in Belgium and 2,084 of them underwent surgery. After adjusting for patient and tumour characteristics, a relationship between hospital surgical volume and patients' outcome was found. Postoperative mortality and survival improved with increasing annual surgical volume up to 10 interventions. However, no further gain in outcome has been observed above 10. While the 60-day postoperative mortality is 3.5% for hospitals with an annual volume larger than 10, the predicted mortality rate for a hospital with an annual volume of only 5 interventions is 6.5%. Similar results were observed for 1- and 3-year OS. CONCLUSION: In Belgium, a higher hospital surgical volume is associated with improved outcome in NSCLC patients after surgical resection. Minimally 10 surgical interventions per year seem to be required to achieve an optimal performance.
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Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Hospitais com Alto Volume de Atendimentos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/cirurgia , Idoso , Idoso de 80 Anos ou mais , Bélgica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Sistema de Registros , Taxa de SobrevidaRESUMO
Emission of ionizing radiation (IR) in the environment is a natural phenomenon which can be enhanced by human activities. Ecosystems are then chronically exposed to IR. But environmental risk assessment of chronic exposure suffers from a lack of knowledge. Extrapolation of data from acute to chronic exposure is not always relevant, and can lead to uncertainties as effects could be different between the two irradiation modes, especially regarding reproduction endpoint, which is an ecologically relevant parameter. In the present study, we decided to refine the understanding of the molecular mechanisms involved in response to acute and chronic γ-irradiation by a global proteome label free LC-MS/MS analysis. C. elegans were exposed to 3 common cumulated radiation doses for acute or chronic exposure condition and global modification of the proteome was studied. This analysis of protein expression has demonstrated the modulation of proteins involved in regulatory biological processes such as lipid transport, DNA replication, germ cell development, apoptosis, ion transport, cuticle development, and aging at lower doses than those for which individual effects on reproduction have been previously observed. Thus, these proteins could constitute early and sensitive markers of radio-induced reprotoxicity; more specifically HAT-1, RPS-19 in acute and VIT-3 for chronic conditions that are expressed in a dose-dependent manner. Finally, to focus on reproduction process, this analysis showed either repression or overexpression of 12 common proteins in organisms exposed to acute or chronic irradiation, respectively. These proteins include the vitellogenin cluster notably involved in lipid transport and oocyte maturation and proteins involved in cuticle development and molting i.e. COL-14, GLF-1, NOAH-1, NOAH-2, ACN-1. These results show that protein expression modulation is a sensitive and predictive marker of radio-induced reproductive effects, but also highlight limitation of data extrapolation from acute to chronic exposure for environmental risk assessment.
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Caenorhabditis elegans/efeitos da radiação , Raios gama , Proteoma/efeitos da radiação , Radiação Ionizante , Animais , Caenorhabditis elegans/fisiologia , Proteínas de Caenorhabditis elegans/metabolismo , Relação Dose-Resposta à Radiação , ReproduçãoRESUMO
Living species are chronically exposed to environmental ionizing radiations from sources that can be overexpressed by nuclear accidents. In invertebrates, reproduction is the most radiosensitive studied endpoint, likely to be connected with aging. Surprisingly, aging is a sparsely investigated endpoint after chronic ionizing radiation, whereas understanding it is of fundamental interest in biology and medicine. Indeed, aging and aging-related diseases (e.g., cancer and degenerative diseases) cause about 90% of deaths in developed countries. Therefore, glp-1 sterile Caenorhabditis elegans nematode was used to assess the impact of chronic gamma irradiation on the lifespan. Analyses were performed, at the individual level, on aging and, in order to delve deeper into the mechanisms, at the molecular level, on oxidative damage (carbonylation), biomolecules (lipids, proteins and nucleic acids) and their colocalization. We observed that ionizing radiation accelerates aging (whatever the duration (3-19 days)/dose (0.5-24â¯Gy)/dose rate (7 and 52â¯mGyâ¯h-1) tested) leading to a longevity value equivalent to that of wt nematode (â¼25-30 days). Moreover, the level of protein oxidative damage (carbonylation) turned out to be good cellular biomarker of aging, since it increases with age. Conversely, chronic radiation treatments reduced carbonylation levels and induced neutral lipid catabolism whatever the dose rate and the final delivered dose. Finally, under some conditions a lipid-protein colocalization without any carbonyl was observed; this could be linked to yolk accumulation in glp-1 nematodes. To conclude, we noticed through this study a link between chronic gamma exposure, lifespan shortening and lipid level decrease associated with a decrease in the overall carbonylation.
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Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Raios gama/efeitos adversos , Longevidade/efeitos da radiação , Mutação , Receptores Notch/genética , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans/genética , Caenorhabditis elegans/efeitos da radiação , Estresse Oxidativo/efeitos da radiação , Tolerância a RadiaçãoRESUMO
PURPOSE: In light of the international evolutions to establish inclusive trauma systems and to concentrate the care for the most severely injured in major trauma centres, we evaluated the degree of dispersion of trauma care in Belgium. METHODS: We used descriptive statistics to illustrate the dispersion of major trauma care in Belgium based on two independent administrative databases: the registry of Mobile Intensive Care Units (2009-2015) and the Belgian Hospital Discharge Dataset (2009-2014). RESULTS: Patients with a severe trauma (n = 3856 in 2015) were transported towards 145 different hospital sites (on a total of 198 hospital sites) resulting in a median of 17 cases per hospital site (min = 1; P25 = 4; P75 = 30; max = 165). A minority of major trauma patients is after admission transferred to another hospital (8%) with a median of 10 days after admission to the hospital (IQR 3.5-24). CONCLUSIONS: The dispersion of care for major trauma patients in Belgium is so high that a reorganisation of care for severe injured patients in major trauma centres concentrating professional expertise and specialised equipment is recommended to guarantee a high quality of care in a qualitative and sustainable way.
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Atenção à Saúde/organização & administração , Reforma dos Serviços de Saúde/organização & administração , Melhoria de Qualidade/organização & administração , Centros de Traumatologia , Ferimentos e Lesões/terapia , Bélgica/epidemiologia , Bases de Dados Factuais , Pesquisa sobre Serviços de Saúde , Humanos , Guias de Prática Clínica como Assunto , Ferimentos e Lesões/epidemiologiaRESUMO
Background and Aims: Besides bananas belonging to the AAA triploid Mutika subgroup, which predominates in the Great Lakes countries, other AAA triploids as well as edible AA diploids, locally of considerable cultural weight, are cultivated in East Africa and in the nearby Indian Ocean islands as far as Madagascar. All these varieties call for the genetic identification and characterization of their interrelations on account of their regional socio-economic significance and their potential for banana breeding strategies. Methods: An extensive sampling of all traditional bananas in East Africa and near Indian Ocean islands was genotyped with simple sequence repeat (SSR) markers, with particular emphasis on the diploid forms and on the bananas of the Indian Ocean islands, which remain poorly characterized. Key Results: All the edible AA varieties studied here are genetically homogeneous, constituting a unique subgroup, here called 'Mchare', despite high phenotypic variation and adaptions to highly diverse ecological zones. At triploid level, and besides the well-known AAA Mutika subgroup, at least two other genetically related AAA subgroups specific to this region are identified. Neither of these East African AAA genotypes can be derived directly from the local AA Mchare diploids. However, it is demonstrated that the East African diploids and triploids together belong to the same genetic complex. The geographical distribution of their wild acuminata relatives allowed identification of the original area of this complex in a restricted part of island South-East Asia. The inferred origin leads to consideration of the history of banana introduction in Africa. Linked to biological features, documentation on the embedding of bananas in founding legends and myths and convincing linguistic elements were informative regarding the period and the peoples who introduced these Asian plants into Africa. The results point to the role of Austronesian-speaking peoples who colonized the Indian Ocean islands, particularly Madagascar, and reached the East African coasts. Conclusions: Understanding of the relations between the components of this complex and identifying their Asian wild relatives and related cultivars will be a valuable asset in breeding programmes and will boost the genetic improvement of East African bananas, but also of other globally important subgroups, in particular the AAA Cavendish.
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Diploide , Variação Genética , Musa/genética , Triploidia , África Oriental , Sudeste AsiáticoRESUMO
BACKGROUND: Identifying comorbidities in lung cancer patients is a complex process in population-based studies and no gold standard exists. The current study aims to identify and measure the main comorbidities using administrative health insurance data, which were available on a population-based level. METHOD: A literature search was conducted to identify comorbidities in lung cancer patients and to select Anatomical Therapeutic Chemical codes to measure them. For each patient, the volume of delivered relevant drugs for each comorbidity in the year preceding the diagnosis of lung cancer was computed, based on the Defined Daily Doses reimbursed. Case definition rules were set by comparing the identification of comorbidities via health insurance data with the reporting of them in the medical files in a sample of hospitals. RESULTS: Four comorbidities were identified: chronic respiratory diseases, chronic cardiovascular diseases, diabetes mellitus and renal diseases. A very good to moderate agreement between the prevalence based on medical files versus health insurance data was obtained for diabetes mellitus (kappa = 0.83), chronic cardiovascular diseases (kappa = 0.64), chronic respiratory diseases (kappa = 0.48) but not for renal diseases (kappa = 0.22). Because only 27% of patients having renal diseases recorded in the medical files were identified using health insurance data, this comorbidity was not withheld. Among 12,839 lung cancer patients diagnosed in 2010-2011 in Belgium, 29.7% had chronic respiratory diseases, 57.5% had chronic cardiovascular diseases and 14.1% had diabetes mellitus. DISCUSSION: This study showed that it was possible to capture three major comorbidities in lung cancer patients using administrative health data, namely, diabetes mellitus, chronic cardiovascular diseases, and chronic respiratory diseases. However, the agreement was only moderate for the last one. A prerequisite for using this methodology is that administrative health data are available for all patients.
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Seguro Saúde/estatística & dados numéricos , Neoplasias Pulmonares/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Bélgica/epidemiologia , Doenças Cardiovasculares/epidemiologia , Comorbidade , Diabetes Mellitus/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , PrevalênciaRESUMO
Species are chronically exposed to ionizing radiation, a natural phenomenon which can be enhanced by human activities. The induced toxicity mechanisms still remain unclear and seem depending on the mode of exposure, i.e. acute and chronic. To better understand these phenomena, studies need to be conducted both at the subcellular and individual levels. Proteins, functional molecules in organisms, are the targets of oxidative damage (especially via their carbonylation (PC)) and are likely to be relevant biomarkers. After exposure of Caenorhabditis elegans to either chronic or acute γ rays we showed that hatching success is impacted after acute but not after chronic irradiation. At the molecular level, the carbonylated protein level in relation with dose was slightly different between acute and chronic exposure whereas the proteolytic activity is drastically modified. Indeed, whereas the 20S proteasome activity is inhibited by acute irradiation from 0.5 Gy, it is activated after chronic irradiation from 1 Gy. As expected, the 20S proteasome activity is mainly modified by irradiation whereas the 26S and 30S activity are less changed. This study provides preliminaries clues to understand the role of protein oxidation and proteolytic activity in the radiation-induced molecular mechanisms after chronic versus acute irradiation in C. elegans.
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Caenorhabditis elegans/efeitos da radiação , Raios gama , Complexo de Endopeptidases do Proteassoma/metabolismo , Animais , Relação Dose-Resposta à Radiação , Cinética , Carbonilação Proteica/efeitos da radiação , Proteólise/efeitos da radiação , Reprodução/efeitos da radiaçãoRESUMO
OBJECTIVE: To evaluate the quality of care for all patients diagnosed with lung cancer in Belgium based on a set of evidence-based quality indicators and to study the variability of care between hospitals. DESIGN, SETTING, PARTICIPANTS: A retrospective study based on linked data from the cancer registry, insurance claims and vital status for all patients diagnosed with lung cancer between 2010 and 2011. Evidence-based quality indicators were identified from a systematic literature search. A specific algorithm to attribute patients to a centre was developed, and funnel plots were used to assess variability of care between centres. INTERVENTION: None. MAIN OUTCOME MEASURE: The proportion of patients who received appropriate care as defined by the indicator. Secondary outcome included the variability of care between centres. RESULTS: Twenty indicators were measured for a total of 12 839 patients. Good results were achieved for 60-day post-surgical mortality (3.9%), histopathological confirmation of diagnosis (93%) and for the use of PET-CT before treatment with curative intent (94%). Areas to be improved include the reporting of staging information to the Belgian Cancer Registry (80%), the use of brain imaging for clinical stage III patients eligible for curative treatment (79%), and the time between diagnosis and start of first active treatment (median 20 days). High variability between centres was observed for several indicators. Twenty-three indicators were found relevant but could not be measured. CONCLUSION: This study highlights the feasibility to develop a multidisciplinary set of quality indicators using population-based data. The main advantage of this approach is that not additional registration is required, but the non-measurability of many relevant indicators is a hamper. It allows however to easily point to areas of large variability in care.
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Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/cirurgia , Indicadores de Qualidade em Assistência à Saúde/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Bélgica , Encéfalo/diagnóstico por imagem , Feminino , Hospitais/estatística & dados numéricos , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/estatística & dados numéricos , Sistema de Registros , Estudos Retrospectivos , Tempo para o Tratamento/estatística & dados numéricosRESUMO
Sorghum is increasingly used as a biomass crop worldwide. Its genetic diversity provides a large range of stem biochemical composition suitable for various end-uses as bioenergy or forage. Its drought tolerance enables it to reasonably sustain biomass production under water limited conditions. However, drought effect on the accumulation of sorghum stem biomass remains poorly understood which limits progress in crop improvement and management. This study aimed at identifying the morphological, biochemical and histological traits underlying biomass accumulation in the sorghum stem and its plasticity in response to water deficit. Two hybrids (G1, G4) different in stem biochemical composition (G4, more lignified, less sweet) were evaluated during 2 years in the field in Southern France, under two water treatments differentiated during stem elongation (irrigated; 1 month dry-down until an average soil water deficit of -8.85 bars). Plant phenology was observed weekly. At the end of the water treatment and at final harvest, plant height, stem and leaf dry-weight and the size, biochemical composition and tissue histology of internodes at 2-4 positions along the stem were measured. Stem biomass accumulation was significantly reduced by drought (in average 42% at the end of the dry-down). This was due to the reduction of the length, but not diameter, of the internodes expanded during water deficit. These internodes had more soluble sugar but lower lignin and cellulose contents. This was associated with a decrease of the areal proportion of lignified cell wall in internode outer zone whereas the areal proportion of this zone was not affected. All internodes for a given genotype and environment followed a common histochemical dynamics. Hemicellulose content and the areal proportion of inner vs. outer internode tissues were set up early during internode growth and were not drought responsive. G4 exhibited a higher drought sensitivity than G1 for plant height only. At final harvest, the stem dry weight was only 18% lower in water deficit (re-watered) compared to well-watered treatment and internodes growing during re-watering were similar to those on the well-watered plants. These results are being valorized to refine the phenotyping of sorghum diversity panels and breeding populations.
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OBJECTIVE: To compare efficacy and safety of tapentadol prolonged-release (PR) and oxycodone-controlled release (CR) in moderate-to-severe chronic osteoarthritis knee pain. METHODS: Data from two double-blind, randomized, placebo- and oxycodone CR-controlled phase 3 studies with a 3-week titration period and 12-week controlled dose adjustment maintenance period were pooled. Primary efficacy end-points were change from baseline in average pain intensity at week 12 (US end-point) and over the entire maintenance period (non-US end-point). RESULTS: A total of 2,010 patients were assessed. For both primary end-points, tapentadol PR was significantly more effective than oxycodone CR (LS mean difference of -0.41 [95% CI = -0.65, -0.16; p = 0.001] at week 12 and -0.35 [95% CI = -0.58, -0.12; p = 0.003] over 12 weeks of maintenance [last observation carried forward]). Significantly better outcomes than for oxycodone CR were also observed for patient global impression of change, both Short Form-36 component scores, and EuroQoL-5Dimensions health status index (all p < 0.001). Relative risk for vomiting, constipation, nausea, somnolence, and pruritus was lower for tapentadol PR than for oxycodone CR. A higher proportion of oxycodone CR patients discontinued treatment (64% vs 42.2% for tapentadol PR); time to treatment discontinuation due to an adverse event was significantly shorter for oxycodone CR (p < 0.001). CONCLUSIONS: The analyses suggest that tapentadol PR provided superior pain relief and a more improved overall health status than oxycodone CR in a large patient population with moderate-to-severe chronic osteoarthritis pain. Compared to oxycodone CR, tapentadol PR showed a more favorable tolerability profile with better gastrointestinal tolerability.
Assuntos
Dor Crônica/tratamento farmacológico , Osteoartrite do Joelho/tratamento farmacológico , Oxicodona/administração & dosagem , Fenóis/administração & dosagem , Idoso , Constipação Intestinal/induzido quimicamente , Preparações de Ação Retardada , Método Duplo-Cego , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Oxicodona/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Tapentadol , Vômito/induzido quimicamenteRESUMO
Internationally the number of emergency department (ED) visits is on the rise while evidence suggests that a substantial proportion of these patients do not require emergency care but primary care. This paper presents the Belgian 2016 proposal for the reorganisation of urgent care provision and places it into its political context. The proposal focused on re-designing patient flow aiming to reduce inappropriate ED visits by improving guidance of patients through the system. Initially policymakers envisaged, as cornerstone of the reform, to roll-out as standard model the co-location of primary care centres and EDs. Yet, this was substantially toned down in the final policy decisions mainly because GPs strongly opposed this model (because of increased workload and loss of autonomy, hospital-centrism, etc.). In fact, the final compromise assures a great degree of autonomy for GPs in organising out-of-hours care. Therefore, improvements will depend on future developments in the field and continuous monitoring of (un-)intended effects is certainly indicated. This policy process makes clear how important it is to involve all relevant stakeholders as early as possible in the development of a reform proposal to take into account their concerns, to illustrate the benefits of the reform and ultimately to gain buy-in for the reform.