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1.
Nature ; 609(7925): 83-88, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36045241

RESUMO

Classical mechanisms of volcanic eruptions mostly involve pressure buildup and magma ascent towards the surface1. Such processes produce geophysical and geochemical signals that may be detected and interpreted as eruption precursors1-3. On 22 May 2021, Mount Nyiragongo (Democratic Republic of the Congo), an open-vent volcano with a persistent lava lake perched within its summit crater, shook up this interpretation by producing an approximately six-hour-long flank eruption without apparent precursors, followed-rather than preceded-by lateral magma motion into the crust. Here we show that this reversed sequence was most likely initiated by a rupture of the edifice, producing deadly lava flows and triggering a voluminous 25-km-long dyke intrusion. The dyke propagated southwards at very shallow depth (less than 500 m) underneath the cities of Goma (Democratic Republic of the Congo) and Gisenyi (Rwanda), as well as Lake Kivu. This volcanic crisis raises new questions about the mechanisms controlling such eruptions and the possibility of facing substantially more hazardous events, such as effusions within densely urbanized areas, phreato-magmatism or a limnic eruption from the gas-rich Lake Kivu. It also more generally highlights the challenges faced with open-vent volcanoes for monitoring, early detection and risk management when a significant volume of magma is stored close to the surface.

2.
Ann Oncol ; 33(2): 158-168, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34718117

RESUMO

BACKGROUND: Coronavirus disease 2019 (COVID-19) has affected >210 million people worldwide. An optimal therapeutic approach for COVID-19 remains uncertain, to date. Since the history of cancer was linked to higher mortality rates due to COVID-19, the establishment of a safe and effective vaccine coverage is crucial in these patients. However, patients with cancer (PsC) were mostly excluded from vaccine candidates' clinical trials. This systematic review aims to investigate the current available evidence about the immunogenicity of COVID-19 vaccines in PsC. PATIENTS AND METHODS: All prospective studies that evaluated the safety and efficacy of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were included, with immunogenicity after the first and the second dose as the primary endpoint, when available. RESULTS: Vaccination against COVID-19 for PsC seems overall safe and immunogenic after well-conducted vaccination schedules. Yet the seroconversion rate remains lower, lagged or both compared to the general population. Patients with hematologic malignancies, especially those receiving B-cell-depleting agents in the past 12 months, are the most at risk of poor seroconversion. CONCLUSION: A tailored approach to vaccination may be proposed to PsC, especially on the basis of the type of malignancy and of the specific oncologic treatments received.


Assuntos
COVID-19 , Neoplasias , Anticorpos Antivirais , Vacinas contra COVID-19 , Humanos , Imunogenicidade da Vacina , Neoplasias/terapia , Estudos Prospectivos , SARS-CoV-2 , Soroconversão , Vacinação
3.
Support Care Cancer ; 28(4): 1639-1647, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31278463

RESUMO

PURPOSE: Anemia is common in oncology and negatively impacts quality of life. However, there is lack of knowledge about iron deficiency (ID) epidemiology. The aim of this study was to prospectively assess iron status in patients with locally advanced or metastatic cancer beginning chemotherapy. METHODS: In this prospective, multicenter cohort study, anemia and ID were evaluated in patients with locally advanced or metastatic solid tumors and lymphoma before starting chemotherapy. Blood samples were collected at inclusion (W0), 6 weeks (W6), and 12 weeks (W12). Prevalence was evaluated in the general population, according to tumor location and was correlated with tumor response. RESULTS: One hundred twenty-nine patients were enrolled between 2013 and 2015; 119 had solid tumors and 10 lymphomas. At W0, there were no significant difference between locations with a prevalence around 50-60% (range 47.2-70.4%) and only a trend for colorectal cancer (70.4%, P = 0.069) due to a higher prevalence of absolute ID (18.5%). Prevalence of ID+ decreased between W0 and W6 and remained stable until W12 due to the proportion of patients with ID and without anemia. However, anemia prevalence increased during W0 and W6 and remained stable to W6 from W12 due to patients with anemia but without ID. A significant correlation between tumor response and ID prevalence was found (P = 0.036). CONCLUSIONS: We confirm the high prevalence of ID and anemia in cancer patients. ID status is correlated to tumor response providing a strong rationale for iron monitoring during cancer management.


Assuntos
Anemia Ferropriva/epidemiologia , Deficiências de Ferro , Distúrbios do Metabolismo do Ferro/epidemiologia , Neoplasias/tratamento farmacológico , Neoplasias/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Anemia Ferropriva/sangue , Anemia Ferropriva/induzido quimicamente , Estudos de Coortes , Feminino , Humanos , Distúrbios do Metabolismo do Ferro/sangue , Distúrbios do Metabolismo do Ferro/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Qualidade de Vida
7.
Oncology ; 86(3): 143-51, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24577186

RESUMO

BACKGROUND: Elderly patients with metastatic breast cancer have a prognosis and outcome that may be dependent on a host of factors. PATIENTS AND METHODS: We retrospectively analyzed 401 female breast cancer patients who developed metastatic disease after the age of 70 years in order to define potential prognostic factors for specific survival at the time of first recurrence. RESULTS: With a median follow-up of 60 months from the time of recurrence, the median specific survival was 21.0 months (95% CI 17.0-23.0). In multivariate analysis we demonstrated that negative hormonal receptor status (p = 0.002), presence of positive lymph nodes at initial cancer diagnosis (hazard ratio, HR = 1.37; 95% CI 1.07-1.75; p = 0.01), site of metastasis (p < 10(-4)) and metastasis-free interval (HR = 0.99; 95% CI 0.95-0.99; p = 0.008) constituted unfavorable independent prognostic factors able to predict specific survival from the time of metastatic occurrence. Age at initial diagnosis, Scarff-Bloom Richardson grade and adjuvant treatments were significant only in univariate analysis. CONCLUSION: These survival prognostic factors associated with the use of a specific geriatric questionnaire to assess frailty may assist physicians in evaluating the patient's survival potential and choose a tailored treatment to this cancer population.


Assuntos
Neoplasias da Mama/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/secundário , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/secundário , Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Quimioterapia Adjuvante , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/secundário , Excisão de Linfonodo , Metástase Linfática , Mastectomia , Mastectomia Segmentar , Prognóstico , Radioterapia Adjuvante , Estudos Retrospectivos , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/secundário , Taxa de Sobrevida , Resultado do Tratamento
8.
Oncology ; 81(2): 73-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21968516

RESUMO

BACKGROUND: Despite current treatment options, metastatic breast cancer (MBC) remains essentially incurable, requiring research on new drugs or combinations to improve survival and quality of life. PATIENTS AND METHODS: This phase I study was designed to define the maximum-tolerated dose (MTD), dose-limiting toxicity (DLT) and recommended dose of all-oral tegafur-uracil (UFT)/folinic acid combined with vinorelbine as chemotherapy for MBC. Starting doses were 40 mg/m(2)/week of oral vinorelbine administered continuously and 250 mg/m(2)/day of UFT plus 90 mg/day of folinic acid from day 1 to day 28, followed by a 1-week rest period. RESULTS: Ten patients were included. Eight were evaluable for toxicity and antitumor response. The second dose level was shown to be the MTD. At this dose, 2 out of 5 patients receiving oral vinorelbine at 40 mg/m(2)/week and UFT at 300 mg/m(2)/day developed DLT consisting of grade 3 asthenia and grade 3 nausea despite standard prophylaxis. Other toxicities were grade 1 diarrhea and anemia. There were no treatment-related deaths. CONCLUSIONS: The recommended dose for this combination seems to be the first dose level. A stable response was observed for 6 patients (average 33 weeks). This combination appears to be well-tolerated and offers an alternative to intravenous chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Administração Oral , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/patologia , Feminino , Humanos , Leucovorina/administração & dosagem , Dose Máxima Tolerável , Pessoa de Meia-Idade , Metástase Neoplásica , Tegafur/administração & dosagem , Tegafur/efeitos adversos , Uracila/administração & dosagem , Uracila/efeitos adversos , Vimblastina/administração & dosagem , Vimblastina/efeitos adversos , Vimblastina/análogos & derivados , Vinorelbina
9.
Prog Urol ; 19(2): 85-93, 2009 Feb.
Artigo em Francês | MEDLINE | ID: mdl-19168010

RESUMO

Radical cystectomy is the treatment of choice for nonmetastatic, muscle-infiltrating bladder cancer. However, bladder-sparing approaches can be discussed in carefully selected patients. Bladder-preservation protocols aim to guaranty local control and survival with a functional bladder and a good quality of life. Such strategies include combinations of transurethral resection and radiochemotherapy, partial cystectomy and brachytherapy, radiotherapy-cystotomy and electrontherapy. Strict selection criteria and close follow-up are mandatory. New irradiation techniques hold the promise to improve local control by selectively boosting the dose to the tumor while better sparing the organs at risk. Such advances include the use of multimodal imaging, image-guided radiotherapy, concomitant boost with conformal irradiation+/-intensity modulated radiation therapy. Brachytherapy, either high-dose or pulsed-rate, is a promising technique for selected cases. Highly-conformal irradiation with tumor tracking using the Cyberknifetrade mark technology may also provide opportunities to boost the tumor while reducing toxicities. Specific innovative irradiation techniques are discussed.


Assuntos
Neoplasias da Bexiga Urinária/radioterapia , Humanos , Radioterapia/métodos , Radioterapia/tendências
10.
Respir Med Res ; 76: 38-44, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31527016

RESUMO

BACKGROUND: Patients with metastatic non-small-cell lung cancer (NSCLC) who survive more than 2 years are considered long-term survivors (LTSs). The present study examined factors associated with long-term survival and collected information for future comparison. METHODS: Clinical, molecular, and therapeutic data were collected from patients followed for primary stage IV (7th TNM classification) NSCLC within 2 years from diagnosis in the respiratory medicine departments of 53 French non-teaching hospitals. LTS and non-LTS records were compared. Factors associated with long-term survival were examined by univariate and multivariate analyses using logistic regression models. RESULTS: Vital status at least 2 years after diagnosis was known for 1977 stage IV NSCLC patients; 220 (11.1%) were LTSs. On multivariate analysis, independent positive factors comprised: TTF-1(+) immunochemistry, EGFR-mutation, surgery, rescue radiotherapy, and targeted therapy. Independent negative factors comprised: prediagnosis weight loss>5kg, ECOG performance status>1, and primary radiotherapy. CONCLUSIONS: Molecular biology and targeted therapy were decisive for long-term survival. With their development and their widespread implementation in clinical practice, the percentage of LTSs is expected to grow. Factors determining long-term survival found in this study should be taken into account when considering treatment options for patients with stage IV NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Feminino , França/epidemiologia , Predisposição Genética para Doença , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Fatores de Risco , Análise de Sobrevida
11.
Ann Oncol ; 19(12): 2012-9, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18641006

RESUMO

BACKGROUND: Treatment of metastatic breast cancer (MBC) remains palliative. Patients with MBC represent a heterogeneous group whose prognosis and outcome may be dependent on host factors. The purpose of the present study was dual: first, to draw up a list of factors easily available in everyday clinical practice requiring no sophisticated or costly methods and second, to provide results from a large cohort of women who underwent diagnostic and treatment at a single institution. PATIENTS AND METHODS: From 1975 to 2005, a total of 1,038 women with MBC during their follow-up were included in this retrospective analysis. Patients were subsequently assigned to five groups according to the period of metastatic diagnosis. RESULTS: It is shown that age at initial diagnosis, hormonal receptor status and site of metastasis are the most relevant prognostic factors for predicting survival from the time of metastastic occurrence. It is also shown that a metastasis-free interval is an easily and immediately available multifactorial prognostic index reflecting the multiparametric variability of the disease. CONCLUSION: These fundamental observations may assist physicians in evaluating the survival potential of patients and in directing them toward the appropriate therapeutic decision.


Assuntos
Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Neoplasias Hormônio-Dependentes/mortalidade , Neoplasias Hormônio-Dependentes/patologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Quimioterapia Adjuvante , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Prognóstico , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Estudos Retrospectivos
12.
Crit Rev Oncol Hematol ; 125: 48-50, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29650276

RESUMO

Pulmonary blastomas represent about 0.5% of primary pulmonary malignancies. The prognosis is poor. Standard treatment consists of surgical excision. There are no published series on which to judge the efficacy of chemotherapy or radiation therapy. We describe an unusual case of classic biphasic pulmonary blastoma (CBPC), with long-term survival despite numerous and varied cancer-related events and review the literature. Our 71-year-old Caucasian woman presented with history of blood in sputum in 2009. Right lower lobectomy yielded a diagnosis of sarcomatoid carcinoma (pneumoblastoma). Unusually, our patient is still alive 7 years after initial surgery, despite metastatic first relapse after 2 years. Metastatic progression was confirmed histologically on three separate occasions during the disease course. The patient received a combination of cisplatin (or carboplatin) and etoposide on three separate occasions. Molecular biology studies of CBPC are needed to identify effective treatments, and a patient registry should be created.


Assuntos
Neoplasias Pulmonares , Blastoma Pulmonar , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cisplatino/administração & dosagem , Terapia Combinada , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Prognóstico , Blastoma Pulmonar/diagnóstico , Blastoma Pulmonar/tratamento farmacológico , Blastoma Pulmonar/patologia , Blastoma Pulmonar/cirurgia , Recidiva , Resultado do Tratamento
18.
Curr Pharm Des ; 4(2): 155-80, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10197038

RESUMO

The streptogramins are a class of antibiotics remarkable for their antibacterial activity and their unique mechanism of action. These antibiotics are produced naturally, but the therapeutic use of the natural compounds is limited because they do not dissolve in water. New semisynthetic derivatives, in particular the injectable streptogramin quinupristin/dalfopristin, offer promise for treating the rising number of infections that are caused by multiply resistant bacteria. The streptogramins consist of two structurally unrelated compounds, group A and group B. The group A compounds are polyunsaturated macrolactones: the group B compounds are cyclic hexadepsipeptides. Modifications of the group B components have been mainly performed on the 3-hydroxypicolinoyl, the 4-dimethylaminophenylalanine and the 4-oxo pipecolinic residues. Semi-synthesis on this third residue led to the water-soluble derivative quinupristin. Water-soluble group A derivatives were obtained by Michael addition of aminothiols to the dehydroproline ring of pristinamycin IIA. Followed by oxidation of the intermediate sulfide into the sulfone derivatives (i.e., dalfopristin). Water-soluble derivatives (both group A and group B) can now be obtained at the industrial scale. Modified group B compounds are now also being produced by mutasynthesis, via disruption of the papA gene. Mutasynthesis has proved particularly useful for producing PIB, the group B component of the oral streptogramin RPR 106972. The streptogramins inhibit bacterial growth by disrupting the translation of mRNA into protein. Both the group A and group B compounds bind to the peptidyltransferase domain of the bacterial ribosome. The group A compounds interfere with the elongation of the polypeptide chain by preventing the binding of aa-tRNA to the ribosome and the formation of peptide bonds, while the B compounds stimulate the dissociation of the peptidyl-tRNA and may also interfere with the release of the completed polypeptide by blocking its access to the channel through which it normally leaves the ribosome. The synergy between the group A and group B compounds appears to result from an enhanced affinity of the group B compounds for the ribosome. Apparently, the group A compound induces a conformational change such that B compound binds with greater affinity. The natural streptogramins are produced as mixtures of the group A and B compounds, the combination of which is a more potent antibacterial agent than either type of compound alone. Whereas the type A or type B compound alone has, in vitro and in animal models of infection, a moderate bacteriostatic activity, the combination of the two has strong bacteriostatic activity and often bactericidal activity. Minimal inhibitory concentrations of quinupristin/dalfopristin range from 0.20 to 1 mg/l for Streptococcus pneumonae, from 0.25 to 2 mg/l for Staphylococcus aureus and from 0.50 to 4 for Enterococcus faecium, the principal target organisms of this drug. Quinupristin/dalfopristin also has activity against mycoplasmas, Neisseria gonorrhoeae, Haemophilus influenz, Legionella spp. and Moraxella catarrhalis. Bacteria develop resistance to the streptogramms by ribosomal modification, by producing inactivating enzymes, or by causing an efflux of the antibiotic. Dimethylation of an adenine residue in rRNA, a reaction that is catalyzed by a methylase encoded by the erm gene class, affects the binding of group B compounds (as well as the macrolides and lincosamides; hence, MLSB resistance), but group A and B compounds usually maintain their synergy and their bactericidal effect against MLSB-resistant strains. erm genes are widespread both geographically and throughout numerous bacterial genera. Several types of enzymes (acetyltransferases, hydrolases) have been identified that inactivate the group A or the group B compounds. Genes involved in streptogramin efflux have so far been found only in staphylococci, particularly in coagulase-negative species


Assuntos
Antibacterianos/farmacologia , Virginiamicina/farmacologia , Animais , Antibacterianos/síntese química , Antibacterianos/química , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Resistência Microbiana a Medicamentos , Resistência a Múltiplos Medicamentos , Sinergismo Farmacológico , Humanos , Testes de Sensibilidade Microbiana , Virginiamicina/síntese química , Virginiamicina/química
19.
Lung Cancer ; 18(1): 71-81, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9268949

RESUMO

A Phase I trial of carboplatin therapy was performed on patients with locally advanced non-small cell lung cancer who had been previously treated with cisplatin, mitomycin and a vinca aklaloïd. This was administered as a daily bolus infusion or as a continuous infusion for 6 weeks with concurrent daily thoracic radiation. All patients had to be objective responders or to show no change after chemotherapy. The carboplatin was started at 10 mg/m2 per day, and increased to 15 mg/m2 per day and 20 mg/m2 per day, if treatment was feasible in successive cohorts of at least six patients. The radiation therapy consisted of 62-66 Gray on the tumor and the ipsilateral mediastinal nodes, 50 Gray on the mediastinum and 40-45 Gray on the supraclavicular lymph nodes. Twenty-nine patients took part in this study. Thrombocytopenia was the principal dose-limiting toxicity, with 15 mg/m2 per day of bolus or continuous infusion. Other toxicities included a fall in haemoglobin level, a fall in white-blood cell count, nausea and vomiting. The median survival time was 12 months, but the response rate cannot be determined among patients selected on the basis of response to chemotherapy. The recommended Phase II dose for patients previously treated with cisplatin containing chemotherapy, is 10 mg/m2 per day of either a bolus or continuous infusion.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carboplatina/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Radiossensibilizantes/uso terapêutico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/efeitos adversos , Cisplatino/administração & dosagem , Terapia Combinada , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Radiossensibilizantes/efeitos adversos , Vimblastina/administração & dosagem , Vimblastina/análogos & derivados , Vindesina/administração & dosagem , Vinorelbina
20.
Eur J Med Chem ; 36(6): 561-8, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11525847

RESUMO

A series of O-alkylated tropolones and related alpha-ketohydroxy compounds were evaluated for their biological activities and were shown to present an expected ribonucleotide reductase inhibition and cytotoxicity against some cancer cell lines but no antitubulin activity. Pharmacomodulation studies were realised to understand and enhance the observed activities. These original benzylic, heterocyclic and allylic compounds have been synthesised by a phase-transfer catalysed O-alkylation developed in our laboratories.


Assuntos
Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Ribonucleotídeo Redutases/antagonistas & inibidores , Tropolona/análogos & derivados , Tropolona/farmacologia , Animais , Biopolímeros , Encéfalo , Divisão Celular/efeitos dos fármacos , DNA/biossíntese , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/química , Espectroscopia de Ressonância Magnética , Microtúbulos/química , Microtúbulos/metabolismo , Ribonucleotídeo Redutases/metabolismo , Relação Estrutura-Atividade , Suínos , Tropolona/síntese química , Tropolona/química , Tubulina (Proteína)/metabolismo , Células Tumorais Cultivadas
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