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1.
Data Brief ; 50: 109557, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37753263

RESUMO

Groundwater from various shallow and deep reservoirs converges in interaction with marine waters into the limestone aquifer of the Balaruc peninsula (Thau lagoon, southern France). This aquifer faces temporary phenomena of marine water intrusion through the Vise submarine spring located at -29.5 m below the lagoon level. Since the 1960s, seven flow reversal phenomena have occurred, the last one occurring between 11/28/2020 and 03/14/2022. During these phenomena, which can last from a few weeks to several months, the salty water is absorbed from the lagoon to the conduit of the submarine spring, which leads to the salinization of the underlying karst aquifer. The monitoring of flow, water specific conductivity and water temperature data from the karst submarine spring is a key element of the research project to understand the hydrogeological functioning of the karst aquifer under normal conditions or during flow reversal periods. This monitoring allows the characterization of the (in- or out-) flows at the submarine spring, the evaluation of the volume or mass balances, the identification of the hydrogeological and physico-chemical responses (water temperature, specific conductivity) observed within the karstic aquifer. Here, we present the means implemented offshore to acquire data at the submarine spring over the 06/25/2019 - 12/31/2022 time period together with lagoon water's physico-chemical parameters and levels and onshore groundwater's physico-chemical parameters and levels acquired at springs and boreholes from the karst aquifer.

2.
Proc Math Phys Eng Sci ; 475(2231): 20190556, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31824227

RESUMO

Drops loaded in calcium ions detach from stalactites and impact the underlying stalagmites, thereby allowing these latter to grow through calcite precipitation. Nevertheless, little is known about the influence of the drop free fall and splash dynamics on stalagmite shape and width. Through high-speed imaging of impacting drops on stalagmites from several caves, we observed that the impact point position of the drops is scattered, sometimes over several centimetres. We show that this dispersal has no external cause and must, therefore, be self-induced. Using a Langevin-like equation, we then propose a prediction of the impact point dispersal as a function of the falling height travelled by the drops. We finally show that measured stalagmite widths are correlated to the dispersal in the impact point position of the drop.

3.
J Contam Hydrol ; 206: 18-33, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28965710

RESUMO

In fractured media, solute transport is controlled by advection in open and connected fractures and by matrix diffusion that may be enhanced by chemical weathering of the fracture walls. These phenomena may lead to non-Fickian dispersion characterized by early tracer arrival time, late-time tailing on the breakthrough curves and potential scale effect on transport processes. Here we investigate the scale dependency of these processes by analyzing a series of convergent and push-pull tracer experiments with distance of investigation ranging from 4m to 41m in shallow fractured granite. The small and intermediate distances convergent experiments display a non-Fickian tailing, characterized by a -2 power law slope. However, the largest distance experiment does not display a clear power law behavior and indicates possibly two main pathways. The push-pull experiments show breakthrough curve tailing decreases as the volume of investigation increases, with a power law slope ranging from -3 to -2.3 from the smallest to the largest volume. The multipath model developed by Becker and Shapiro (2003) is used here to evaluate the hypothesis of the independence of flow pathways. The multipath model is found to explain the convergent data, when increasing local dispersivity and reducing the number of pathways with distance which suggest a transition from non-Fickian to Fickian transport at fracture scale. However, this model predicts an increase of tailing with push-pull distance, while the experiments show the opposite trend. This inconsistency may suggest the activation of cross channel mass transfer at larger volume of investigation, which leads to non-reversible heterogeneous advection with scale. This transition from independent channels to connected channels when the volume of investigation increases suggest that both convergent and push-pull breakthrough curves can inform the existence of characteristic length scales.


Assuntos
Hidrologia/métodos , Modelos Teóricos , Difusão , Água Subterrânea , Dióxido de Silício , Movimentos da Água
4.
Chem Commun (Camb) ; 51(13): 2476-94, 2015 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-25493292

RESUMO

The design of artificial hemoproteins that could catalyze selective oxidations using clean oxidants such as O2 or H2O2 under ecocompatible conditions constitutes a real challenge for a wide range of industrial applications. In vivo, such reactions are performed by heme-thiolate proteins, cytochromes P450, which catalyze the oxidation of substrates by dioxygen in the presence of electrons delivered from NADPH by cytochrome P450 reductase. Several strategies were used to design new artificial hemoproteins that mimic these enzymes. The first one involved the non-covalent association of synthetic hemes with monoclonal antibodies raised against these cofactors. This led to the first generation of artificial hemoproteins or "hemoabzymes" that displayed a peroxidase activity, and in some cases catalyzed the regioselective nitration of phenols by H2O2/NO2 and the stereoselective oxidation of sulfides by H2O2. The second one involved the non-covalent association of easily affordable non-relevant proteins with metalloporphyrin derivatives, using either the "Trojan Horse strategy" or the "host-guest" strategy. This led to a second generation of artificial hemoproteins or "hemozymes", some of which were found able to catalyze the stereoselective oxidation of organic compounds such as sulfides and alkenes by H2O2 and KHSO5.


Assuntos
Biocatálise , Ferro/metabolismo , Metaloporfirinas/metabolismo , Porfirinas/metabolismo , Proteínas/metabolismo , Ferro/química , Metaloporfirinas/química , Estrutura Molecular , Oxirredução , Porfirinas/química , Proteínas/química
5.
Biofouling ; 26(7): 769-77, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20818516

RESUMO

This paper focuses on the activity spectrum of three dimethylalkyl tertiary amines as potential active molecules and the corresponding ammonium salt-based antifouling (AF) paints. Bioassays (using marine bacteria, microalgae and barnacles) and field tests were combined to assess the AF activity of coatings. Bioassay results demonstrated that the ammonium salt-based paints did not inhibit the growth of microorganisms (except the dimethyldodecylammonium-based coatings) and that the tertiary amines were potent towards bacteria, diatoms, and barnacle larvae at non-toxic concentrations (therapeutic ratio, LC50/EC50, <1). The results from field tests indicated that the ammonium salt-based coatings inhibited the settlement of macrofouling and the dimethylhexadecylammonium-based coatings provided protection against slime in comparison with PVC blank panels. Thus, results from laboratory assays did not fully concur with the AF activity of the paints in the field trial.


Assuntos
Organismos Aquáticos , Incrustação Biológica/prevenção & controle , Bioensaio , Cobre/química , Pintura/análise , Ácidos Polimetacrílicos/química , Compostos de Amônio Quaternário/química , Adesivos/química , Animais , Organismos Aquáticos/efeitos dos fármacos , Organismos Aquáticos/fisiologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo , Ácidos Carboxílicos/química , Técnicas de Laboratório Clínico , Diatomáceas/efeitos dos fármacos , Diatomáceas/fisiologia , Contaminação de Equipamentos/prevenção & controle , Imersão , Resinas de Troca Iônica/química , Microalgas/efeitos dos fármacos , Microalgas/fisiologia , Compostos de Amônio Quaternário/toxicidade , Thoracica/efeitos dos fármacos , Thoracica/fisiologia
6.
Br J Pharmacol ; 153 Suppl 1: S82-9, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18026129

RESUMO

The cytochromes P450 (CYPs) comprise a vast superfamily of enzymes found in virtually all life forms. In mammals, xenobiotic metabolizing CYPs provide crucial protection from the effects of exposure to a wide variety of chemicals, including environmental toxins and therapeutic drugs. Ideally, the information on the possible metabolism by CYPs required during drug development would be obtained from crystal structures of all the CYPs of interest. For some years only crystal structures of distantly related bacterial CYPs were available and homology modelling techniques were used to bridge the gap and produce structural models of human CYPs, and thereby obtain useful functional information. A significant step forward in the reliability of these models came seven years ago with the first crystal structure of a mammalian CYP, rabbit CYP2C5, followed by the structures of six human enzymes, CYP1A2, CYP2A6, CYP2C8, CYP2C9, CYP2D6 and CYP3A4, and a second rabbit enzyme, CYP2B4. In this review we describe as a case study the evolution of a CYP2D6 model, leading to the validation of the model as an in silico tool for predicting binding and metabolism. This work has led directly to the successful design of CYP2D6 mutants with novel activity-including creating a testosterone hydroxylase, converting quinidine from inhibitor to substrate, creating a diclofenac hydroxylase and creating a dextromethorphan O-demethylase. Our modelling-derived hypothesis-driven integrated interdisciplinary studies have given key insight into the molecular determinants of CYP2D6 and other important drug metabolizing enzymes.


Assuntos
Citocromo P-450 CYP2D6/química , Citocromo P-450 CYP2D6/efeitos dos fármacos , Sistema Enzimático do Citocromo P-450/química , Sistema Enzimático do Citocromo P-450/metabolismo , Preparações Farmacêuticas/metabolismo , Animais , Sistema Enzimático do Citocromo P-450/efeitos dos fármacos , Interações Medicamentosas , Humanos , Modelos Moleculares , Especificidade por Substrato
7.
Br J Cancer ; 90(1): 100-5, 2004 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-14710214

RESUMO

Based on the results of combined data from three North American Phase II studies, a randomised Phase II study in the same patient population was performed, using combination chemotherapy with estramustine phosphate (EMP) and vinblastine (VBL) in hormone refractory prostate cancer patients. In all, 92 patients were randomised into a Phase II study of oral EMP (10 mg kg day continuously) or oral EMP in combination with intravenous VBL (4 mg m(2) week for 6 weeks, followed by 2 weeks rest). The end points were toxicity and PSA response in both groups, with the option to continue the trial as a Phase III study with time to progression and survival as end points, if sufficient responses were observed. Toxicity was unexpectedly high in both treatment arms and led to treatment withdrawal or refusal in 49% of all patients, predominantly already during the first treatment cycle. The mean treatment duration was 10 and 14 weeks, median time to PSA progression was 27.2 and 30.8 weeks, median survival time was 44 and 50.9 weeks, and PSA response rate was only 24.6 and 28.9% in the EMP/VBL and EMP arms, respectively. There was no correlation between PSA response and survival. While the PSA response in the patients tested was less than half that recorded in the North American studies, the toxicity of EMP monotherapy or in combination with VBL was much higher than expected. Further research on more effective and less toxic treatment strategies for hormone refractory prostate cancer is mandatory.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Administração Oral , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos , Estramustina/administração & dosagem , Estramustina/efeitos adversos , Humanos , Infusões Intravenosas , Masculino , Antígeno Prostático Específico/análise , Neoplasias da Próstata/patologia , Análise de Sobrevida , Vimblastina/administração & dosagem , Vimblastina/efeitos adversos
8.
Ann Urol (Paris) ; 37(4): 170-2, 2003 Aug.
Artigo em Francês | MEDLINE | ID: mdl-12951706

RESUMO

Cystic lymphangioma of the adrenal gland are rarely encountered tumoural formations with no clinical expression. Pre-operative diagnosis is difficult. Echography and CT scan are essential exploratory techniques, diagnosis is histological. Usually surgical exploration is indicated due to uncertain diagnosis. We report a new case of cystic lymphangioma of the adrenal gland and a review of recent literature.


Assuntos
Neoplasias das Glândulas Suprarrenais/patologia , Linfangioma Cístico/patologia , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Neoplasias das Glândulas Suprarrenais/cirurgia , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Linfangioma Cístico/diagnóstico por imagem , Linfangioma Cístico/cirurgia , Prognóstico , Tomografia Computadorizada por Raios X , Ultrassonografia
9.
Urology ; 60(1): 164, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12100948

RESUMO

Giant renal cysts measuring more than 15 cm in greatest diameter are uncommon and the association with erythrocytosis and hypertension is very rare. We present a case of a 22-year-old man with an incidental giant left renal cyst associated with hypertension and polycythemia that was treated by drainage and laparoscopic excision, followed by resolution of both hypertension and erythrocytosis.


Assuntos
Hipertensão Renal/epidemiologia , Doenças Renais Císticas/cirurgia , Policitemia/epidemiologia , Adulto , Comorbidade , Humanos , Doenças Renais Císticas/diagnóstico , Doenças Renais Císticas/epidemiologia , Masculino , Período Pós-Operatório , Remissão Espontânea
11.
Can J Microbiol ; 47(6): 541-7, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11467730

RESUMO

Two-dimensional (2-D) polyacrylamide gel electrophoresis was used to detect proteins induced in Frankia sp. strain ACN14a-tsr by root exudates of its symbiotic host, Alnus glutinosa. The 5 most prominent proteins were purified from 2-D gels and characterized by N-terminal sequencing. All of these proteins had a high percentage of similarity with known stress proteins. One protein match was the Fe superoxide dismutase (Fe-SOD), another was a tellurite resistance protein (Ter), the third was a bacterioferritin comigratory protein (Bcp); and two matches, differing only by their isoelectric point, were the same small heat shock protein (Hsp), a major immune reactive protein found in mycobacteria. This suggests that the symbiotic microorganism Frankia, first responds with a normal stress response to toxic root products of its symbiotic host plant. To confirm its identity, the gene corresponding to the Fe-SOD protein, sodF was isolated from a genomic library by a PCR-approach and sequenced. It is the first stress response gene characterized in Frankia.


Assuntos
Actinomycetales/crescimento & desenvolvimento , Alnus/microbiologia , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Raízes de Plantas/metabolismo , Superóxido Dismutase/genética , Actinomycetales/genética , Actinomycetales/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Sequência de Bases , Clonagem Molecular , Eletroforese em Gel Bidimensional , Resposta ao Choque Térmico , Dados de Sequência Molecular , Fixação de Nitrogênio , Análise de Sequência de DNA , Superóxido Dismutase/metabolismo , Simbiose
12.
Ann Urol (Paris) ; 35(6): 323-8, 2001 Nov.
Artigo em Francês | MEDLINE | ID: mdl-11774764

RESUMO

The pheochromocytoma is a medullo-adrenal tumor which develops at the cost of the chromaffin cells. It appears in 11-19% of cases of von Hippel-Lindau's disease (VHL), is often bilateral, and the symptomatology is often crude: arterial hypertension is frequently isolated and unstable, and the classic triad of headache, palpitations and sweating is quite rarely observed. We report four observations of bilateral pheochromocytomas in patients with von Hippel-Lindau's disease (three with phenotype IIA and one with phenotype IIB). The tumor was bilateral during the diagnosis in three cases; in the fourth patient, the attack on the contralateral adrenal gland came two years after the first adrenalectomy. All the patients had undergone an adrenalectomy by open surgery after a short preparation of 48 hours; replacement therapy was begun in each patient. Morbidity was low, and the patients submitted to a prolonged follow-up in order to screen for the onset of future lesions of VHL.


Assuntos
Neoplasias das Glândulas Suprarrenais/etiologia , Neoplasias Primárias Múltiplas/etiologia , Feocromocitoma/etiologia , Doença de von Hippel-Lindau/complicações , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Ann Urol (Paris) ; 35(6): 335-8, 2001 Nov.
Artigo em Francês | MEDLINE | ID: mdl-11774766

RESUMO

UNLABELLED: Obstruction of the lower ureter by pelvic cancer requires a palliative treatment. Percutaneous derivation is often performed as an emergency. If obstruction is limited to the peri-meatic area (a few mm or a cm) resection of the ureteral orifice can be enough to catheterize the obstructed ureter. Stenting of the ureter can be done even if the obstruction is longer, using the extra vesical repermeabilization. METHODS: A guide wire is passed via the nephrostomy, and ureteral stent is passed over the guide wire. Dye additionned with methylene blue is injected tovisualize the lower extremity of the ureter. A regular resectoscope is placed transuretraly, and resection is conducted using X ray localisation with a C arm and several incidences. The tissue resected first is usually extravesical, in the adipous perivesical tissue. Dissection of this area can be performed bluntly with the tip of the resectoscope until the ureter is reached. At this time, the resectoscope is used to open the lower extremity of the ureter, localized with the C arm. It is important to open widely the ureter, so as to be sure to catheterize easily this opening with a ureteral catheter. A double J can then be passed easily. Tunnel of several cm can be performed using this technique. RESULTS: Seven patients with pelvic cancer with obstruction of the last cm of the pelvic ureter were included in this series. They were recurrent prostate cancer already treated with hormone therapy, stage T3, T4. All procedures were performed under rachianesthesia or general anesthesia according to general status. After this procedure normal miction were obtain in all patients and nephrostomies were removed. This technique is possible for extended pelvic obstruction. Blunt dissection with the endoscope is usualy blood less. This palliative procedure can be done in patients with poor general condition and allows for a better quality of life than nephrostomy or urinary diversions.


Assuntos
Neoplasias da Próstata/complicações , Obstrução Ureteral/diagnóstico por imagem , Obstrução Ureteral/cirurgia , Ureteroscopia , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Derivação Urinária
14.
Eur J Cancer ; 36(14): 1781-7, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10974626

RESUMO

The intent of this feasibility study was to evaluate the use of intra-operative electron radiotherapy (IOERT), after transurethral resection (TUR), combined with external beam radiation with concurrent chemotherapy for the conservative treatment of infiltrating bladder cancer. From November 1988 to June 1998, 27 patients with histologically proven non-metastatic infiltrating bladder cancer were included in this protocol. The treatment consisted of: TUR, external beam irradiation (x18 MV:48 Grays (Gy)/24 fractions/5 weeks), with concurrent chemotherapy (cisplatin 30 mg/day for 3 days-two cycles during irradiation), followed by control cystoscopy and cystotomy with IOERT (e 9 MeV:15 Gy). 14 patients received two cycles of neoadjuvant methotrexate, vinblastine and cisplatin (MVC) and folinic acid chemotherapy. Patients were evaluated for toxicity, local control and survival. The 5-year overall and cystectomy-free survival rates were 53.3% +/-11.1% and 48.1%+/-11.4%, respectively. 4 patients developed infiltrating intravesicular recurrence (3 were treated by salvage cystectomy), and an additional patient developed a superficial recurrence. 2 patients subsequently developed regional recurrence in pelvic nodes and 10 patients were found to have distant metastases. The protocol was found to be feasible and associated with acceptable toxicity. Early and late toxicities consisted of 3 cases of bladder mucosal necrosis or ureteral stenosis which resolved with medical management. These preliminary results indicate that IOERT combined with TUR and neoadjuvant external beam radiation with concurrent chemotherapy is feasible. It could be considered as an alternative therapy for infiltrating carcinoma of the bladder, especially in patients unfit for radical surgery, and is well adapted to treat lesions of the fixed portion of the bladder.


Assuntos
Carcinoma Intraductal não Infiltrante/radioterapia , Elétrons/uso terapêutico , Neoplasias da Bexiga Urinária/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Intraductal não Infiltrante/cirurgia , Intervalo Livre de Doença , Estudos de Viabilidade , Feminino , Humanos , Cuidados Intraoperatórios/métodos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Projetos Piloto , Radioterapia/efeitos adversos , Neoplasias da Bexiga Urinária/cirurgia
15.
Int J Syst Evol Microbiol ; 50 Pt 2: 781-785, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10758889

RESUMO

The closer proximity of Frankia and Acidothermus cellulolyticus relative to the morphologically close Geodermatophilus found previously was confirmed by resequencing the rrs gene of Acidothermus cellulolyticus and the housekeeping gene, recA. The diagnostic sugar 2-O-methyl-D-mannose was detected only in Frankia, while hopanoid lipids were present at high levels in both Acidothermus and Frankia.


Assuntos
Actinomycetales/classificação , Actinomycetales/genética , Genes de RNAr , Filogenia , Recombinases Rec A/genética , DNA Bacteriano/genética , DNA Ribossômico/genética , Metabolismo dos Lipídeos , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
20.
Eur Urol ; 36(6): 570-5, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10559610

RESUMO

OBJECTIVE: The authors present demographic and surgical data from a randomized phase III trial, instituted by the EORTC Genitourinary Group in 1988, the aim of which was to assess whether complete lymph node dissection in conjunction with radical nephrectomy for renal cell cancer is more effective than radical nephrectomy alone. METHODS: Before surgery, the renal cell carcinoma was staged and judged to be nonmetastatic and resectable. The patients were randomized prior to surgery into those having radical nephrectomy combined with complete lymph node dissection or into those having radical nephrectomy alone. Postoperatively all patients were followed until progression of disease or death. RESULTS: Of the 772 randomized patients, 41 were not eligible. 383 had a complete lymph node dissection together with a radical nephrectomy. 389 had a radical nephrectomy alone. The complication rate did not differ significantly between the two groups. A complete lymph node dissection in 336 patients revealed absence of lymph node metastases in 325 of them. CONCLUSIONS: The present study shows that complete lymph node dissection does not add morbidity to the radical nephrectomy. After proper preoperative staging, the incidence of unsuspected lymph node metastases is low (3.3%).


Assuntos
Adenocarcinoma/cirurgia , Carcinoma de Células Renais/cirurgia , Neoplasias Renais/cirurgia , Excisão de Linfonodo , Nefrectomia , Adenocarcinoma/patologia , Carcinoma de Células Renais/patologia , Distribuição de Qui-Quadrado , Feminino , Humanos , Neoplasias Renais/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Taxa de Sobrevida , Resultado do Tratamento
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