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1.
Water Res ; 254: 121382, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38471202

RESUMO

Electrodialysis is a water desalination technology that enables selective separation of ions, making it a promising solution for sustainable water reuse. The selectivity of the process is mainly determined by the properties of ion exchange membranes that can vary depending on the composition of ions in water, such as water uptake and charge density. In this work, we studied selective adsorption of Na+ and K+ ions in various ion exchange membranes considering the effect of solution ion composition on membrane water volume fraction. For that purpose, we conducted membrane adsorption experiments using solutions with Na+ and K+ ions with different ion compositions including Li+, Ca2+ or Mg2+ ions at different concentrations (0.001 - 0.25 M). The experiments showed that with the total ion concentration and the amount of divalent ions in solution, the membrane water volume fraction decreases while the selective adsorption of the smaller (hydrated) K+ ions over the Na+ ions in the membrane increases. We developed a theoretical framework based on Boublik-Mansoori-Carnahan-Starling-Leland (BMCSL) theory to describe the effect of membrane water volume fraction on selective adsorption of the ions by including volumetric effects, such as size exclusion. The developed framework was used to describe ion partitioning results of the membrane adsorption experiments. In addition, the effect of solution ion composition on selective ion removal during electrodialysis operation was evaluated using experimental data and theoretical calculations. The results of this study show that considering volumetric effects can improve the ion partitioning description in ion exchange membranes for solutions with various ion compositions.


Assuntos
Sódio , Água , Troca Iônica , Adsorção , Íons
2.
J Colloid Interface Sci ; 584: 634-646, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33176931

RESUMO

HYPOTHESIS: Cation exchange membranes (CEMs) are subject to fouling when utilized to desalinate wastewater from the oil and gas industry, hampering their performance. The kind and extent of the fouling are most likely dependent on the composition of the stream, which in practical applications can vary significantly. EXPERIMENTS: Fouling experiments were performed on commercial cation exchange membranes, which were used in electrodialysis runs to desalinate solutions of varying composition. The variations included ionic strength, type of ions, amount of viscosifying polyelectrolyte (partially hydrolyzed polyacrylamide), presence of crude oil, and surfactants. Performance parameters, like electric potential and pH, were monitored during the runs, after which the membranes were recovered and analyzed. FINDINGS: Fouling was detected on most CEMs and occurred mainly in the presence of the viscosifying polyelectrolyte. Under normal pH conditions (pH ~ 8), the polyelectrolyte fouled the concentrate side of the CEMs, as expected due to electrophoresis. However, by applying a current in the opposite direction, the polyelectrolyte layer could be removed. Precipitation occurred mostly on the opposite side of the membrane, with different morphology depending on the feed composition.

3.
J Colloid Interface Sci ; 557: 381-394, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31539838

RESUMO

HYPOTHESIS: Anion exchange membranes (AEMS) are particularly prone to fouling when employed to desalinate polymer flooding produced water (PFPW), an abundant sub-product from the oil and gas industry. The formation of fouling on an AEM will be affected by the composition of the solution, which includes various dissolved salts, partially hydrolyzed polyacrylamide (HPAM), crude oil, and surfactants. EXPERIMENTS: Electrodialysis experiments were performed to desalinate feed solutions with different compositions, aiming to distinguish between their individual and combined effects. The solutions contained diverse mono- and divalent ions. The analysis included data collected during the desalination and characterization of the fouled AEMs by diverse analytical techniques. FINDINGS: HPAM produced the most severe effects in terms of visible fouling and increase of resistance. This polyelectrolyte fouls the AEM by adsorbing on its surface and by forming a viscous gel layer that hampers the replenishment of ions from the bulk solution. Ca and Mg have a large influence on the formation of thick HPAM gel layers, while the oily compounds have only a minimal influence acting mainly as a destabilizing agent. The membranes also presented scaling consisting of calcium precipitates. The effects of the gel layer were minimized by applying current reversal and foulant-free solution.

4.
Br J Dermatol ; 180(2): 297-305, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30171698

RESUMO

BACKGROUND: Topical immune response modifiers are established for actinic keratosis (AK) treatment and efforts are underway to make further improvements to their efficacy and safety. OBJECTIVES: To investigate the optimal dosing regimens of the Toll-like receptor 7/8 agonist resiquimod in terms of efficacy, safety and tolerability. METHODS: In a multicentre, partly placebo-controlled, double-blind clinical trial, we randomized 217 patients with AK lesions to 0·03% resiquimod gel once-daily application three times per week for 4 weeks or seven times within 2 weeks or five times for 1 week (arms 1/2/3) followed by a treatment-free interval of 8 weeks and one repetition of the cycle. In two additional arms (arms 4/5), patients applied either resiquimod gel 0·01% or 0·03% three times per week up to a biological end point defined by skin erosion or for a maximum duration of 8 weeks. Clearance was assessed clinically and histologically. RESULTS: Complete clinical clearance ranged from 56% to 85% with the highest rate observed in arm 2. Resiquimod 0·03% gel was more effective than 0·01% gel. Clearance rates in arms 1/2/3 were comparable and higher than with placebo and were reached with 24, 14 and 10 gel applications, respectively. Overall, 128 patients (59%) experienced treatment-related adverse reactions. CONCLUSIONS: Resiquimod 0·03% gel is more effective than 0·01% gel. From the perspectives of safety and tolerability, the lower concentration and shorter duration are preferable. The clinical response in arms 2/3 was reached with fewer gel applications. The dosing regimens that used the biological end point (arms 4/5) proved equally efficacious as predefined treatment durations and may therefore be suitable for personalized AK treatment.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Imidazóis/administração & dosagem , Ceratose Actínica/tratamento farmacológico , Adjuvantes Imunológicos/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Imidazóis/efeitos adversos , Ceratose Actínica/imunologia , Masculino , Pessoa de Meia-Idade , Placebos/administração & dosagem , Placebos/efeitos adversos , Fatores de Tempo , Receptor 7 Toll-Like/agonistas , Receptor 7 Toll-Like/imunologia , Receptor 8 Toll-Like/agonistas , Receptor 8 Toll-Like/imunologia , Resultado do Tratamento
5.
Allergy ; 72(8): 1243-1253, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27998002

RESUMO

BACKGROUND: Conflicting results exist on the effect of allergen immunotherapy (AIT) on pollen-related food allergy. We aimed to investigate the efficacy of one-year AIT with the folding variant (FV) of recombinant (r) Bet v 1 on birch-related soya allergy. METHODS: Of 138 subjects with Bet v 1 sensitization, 82 were positive at double-blind placebo-controlled food challenge (DBPCFC) with soya. A total of 56 of 82 were randomized in the ratio of 2:1 (active: placebo). Per-protocol population (PPP) had received ≥150 µg of allergen or placebo preparation. OUTCOME MEASURES: lowest observed adverse effect levels (LOAEL), postinterventional occurrence of objective signs (objS) at any dose level, sIgE/IgG4 against Bet v 1 and Gly m 4. Between-group changes were investigated (ancova, Mann-Whitney U-test, Fisher exact test). RESULTS: Baseline characteristics including LOAELs were comparable in both groups with objS and subjS occurring in 82% and 95% of active (n = 38) vs 78% and 83% of placebo group (n = 18). After AIT, objS occurred in 24% and 47%, respectively. LOAEL group differences showed a beneficial tendency (P = 0.081) for LOAELobjective in PPP (30 active, 15 placebo). sIgG4 raised only in active group (Bet v 1: P = 0.054, Gly m 4: P = 0.037), and no relevant changes occurred for sIgE. Only 56% of the intended sample size was recruited. CONCLUSION: For the first time, we present data on the effect of rBet v 1-FV on birch-related soya allergy. rBet v 1-FV AIT induced significant immunogenic effects. Clinical assessment showed a tendency in favour of the active group but did not reach statistical significance.


Assuntos
Antígenos de Plantas/imunologia , Betula/imunologia , Dessensibilização Imunológica , Hipersensibilidade Alimentar/imunologia , Hipersensibilidade Alimentar/terapia , Glycine max/efeitos adversos , Rinite Alérgica Sazonal/imunologia , Rinite Alérgica Sazonal/terapia , Adulto , Dessensibilização Imunológica/efeitos adversos , Dessensibilização Imunológica/métodos , Feminino , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Rinite Alérgica Sazonal/diagnóstico , Testes Cutâneos , Resultado do Tratamento
6.
Clin Transl Allergy ; 6: 39, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27826414

RESUMO

BACKGROUND: Multicentre trials investigating food allergies by double blind placebo controlled food challenges (DBPCFC) need standardized procedures, challenge meals and evaluation criteria. We aimed at developing a standardized approach for identifying patients with birch related soy allergy by means of DBPCFC to soy, including determination of threshold levels, in a multicentre setting. METHODS: Microbiologically stable soy challenge meals were composed of protein isolate with consistent Gly m 4 levels. Patients sensitized to main birch allergen Bet v 1 and concomitant sensitization to its soy homologue Gly m 4 underwent DBPCFC. Outcome was defined according to presence and/or absence of ten objective signs and intensity of eight subjective symptoms as measured by visual analogue scale (VAS). RESULTS: 138 adult subjects (63.8% female, mean age 38 years) underwent DBPCFC. Challenge meals and defined evaluation criteria showed good applicability in all centres involved. 45.7% presented with objective signs and 65.2% with subjective symptoms at soy challenge. Placebo challenge meals elicited non-cardiovascular objective signs in 11.6%. In 82 (59.4%) subjects DBPCFC was judged as positive. 70.7% of DPBCFC+ showed objective signs and 85.4% subjective symptoms at soy challenge. Subjective symptoms to soy challenge meal in DBPCFC+ subjects started at significantly lower dose levels than objective signs (p < 0.001). Median cumulative eliciting doses for first objective signs in DBPCFC+ subjects were 4.7 g [0.7-24.7] and 0.7 g [0.2-4.7] total soy protein for first subjective symptoms (p = 0.01). CONCLUSIONS: We present the hitherto largest group of adults with Bet v 1 and Gly m 4 sensitization being investigated by DBPCFC. In this type of food allergy evaluation of DBPCFC outcome should not only include monitoring of objective signs but also scoring of subjective symptoms. Our data may contribute to standardize DBPCFC in pollen-related food allergy in multicentre settings. TRIAL REGISTRATION: EudraCT: 2009-011737-27.

7.
Artigo em Inglês | MEDLINE | ID: mdl-25122405

RESUMO

Bioelectrochemical systems recover valuable components and energy in the form of hydrogen or electricity from aqueous organic streams. We derive a one-dimensional steady-state model for ion transport in a bioelectrochemical system, with the ions subject to diffusional and electrical forces. Since most of the ionic species can undergo acid-base reactions, ion transport is combined in our model with infinitely fast ion acid-base equilibrations. The model describes the current-induced ammonia evaporation and recovery at the cathode side of a bioelectrochemical system that runs on an organic stream containing ammonium ions. We identify that the rate of ammonia evaporation depends not only on the current but also on the flow rate of gas in the cathode chamber, the diffusion of ammonia from the cathode back into the anode chamber, through the ion exchange membrane placed in between, and the membrane charge density.


Assuntos
Eletroquímica , Movimento (Física) , Amônia/química , Eletrodos , Hidrogênio/química , Concentração de Íons de Hidrogênio , Troca Iônica , Membranas Artificiais , Pressão , Volatilização
8.
Br J Dermatol ; 168(4): 825-36, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23252768

RESUMO

BACKGROUND: Two phase III trials of photodynamic therapy (PDT) with BF-200 ALA, a recently approved nanoemulsion formulation of 5-aminolaevulinic acid (ALA) demonstrated high clearance rates in mild-to-moderate actinic keratosis (AK). The comparison to a registered methyl aminolaevulinate (MAL) cream demonstrated significantly superior total patient clearance rates. OBJECTIVES: To evaluate long-term efficacy and safety of PDT for AK 6 and 12 months after the last PDT with BF-200 ALA, MAL or placebo. METHODS: The follow-up phase (FUP) was performed with patients of two phase III studies. Both studies compared BF-200 ALA with placebo, one of the studies additionally with MAL. Overall recurrence rates and various subgroups (light source, lesion severity, lesion location, complete responders after first PDT) were assessed 6 and 12 months after the last PDT. RESULTS: Recurrence rates were similar for BF-200 ALA and MAL, with a tendency to lower recurrence rates for BF-200 ALA. The proportion of patients who were fully cleared during PDT and remained completely clear for at least 12 months after PDT were 47% for BF-200 ALA (both studies) and 36% for MAL treatment. The subgroup that was illuminated with narrow wavelength LED lamps reached 69% and 53% for BF-200 ALA (both studies, respectively) and 41% for MAL. No safety concerns were reported. CONCLUSIONS: The FUP data confirmed the high efficacy and safety of PDT with BF-200 ALA. The slightly lower recurrence rates after BF-200 ALA treatment compared with MAL treatment enhanced the better treatment outcome due to the significantly superior efficacy.


Assuntos
Ácido Aminolevulínico/análogos & derivados , Ceratose Actínica/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Ácido Aminolevulínico/administração & dosagem , Ácido Aminolevulínico/efeitos adversos , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Assistência de Longa Duração , Masculino , Pessoa de Meia-Idade , Fármacos Fotossensibilizantes/efeitos adversos , Estudos Prospectivos , Recidiva , Resultado do Tratamento
9.
Opt Express ; 20(12): 13326-36, 2012 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-22714361

RESUMO

Diffraction efficiency, relaxation behavior and dependence on pump-beam intensity of small-polaron based holograms are studied in thermally reduced, nominally undoped lithium niobate in the visible spectrum (λ = 488 nm). The pronounced phase gratings with diffraction efficiency up to η = (10.8 ± 1.0)% appeared upon irradiation by single ns-laser pulses (λ = 532 nm) and are comprehensively assigned to the optical formation of spatially modulated densities of small bound NbLi4+ electron polarons, NbLi4+:NbNb4+ electron bipolarons, and O⁻ hole polarons. A remarkable quadratic dependence on the pump-beam intensity is discovered for the recording configuration K || c-axis and can be explained by the electro-optic contribution of the optically generated small bound polarons. We discuss the build-up of local space-charge fields via small-polaron based bulk photovoltaic currents.

10.
Water Res ; 46(8): 2627-36, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22406284

RESUMO

Nitrogen recovery through NH(3) stripping is energy intensive and requires large amounts of chemicals. Therefore, a microbial fuel cell was developed to simultaneously produce energy and recover ammonium. The applied microbial fuel cell used a gas diffusion cathode. The ammonium transport to the cathode occurred due to migration of ammonium and diffusion of ammonia. In the cathode chamber ionic ammonium was converted to volatile ammonia due to the high pH. Ammonia was recovered from the liquid-gas boundary via volatilization and subsequent absorption into an acid solution. An ammonium recovery rate of 3.29 g(N) d(-1) m(-2) (vs. membrane surface area) was achieved at a current density of 0.50 A m(-2) (vs. membrane surface area). The energy balance showed a surplus of energy 3.46 kJ g(N)(-1), which means more energy was produced than needed for the ammonium recovery. Hence, ammonium recovery and simultaneous energy production from urine was proven possible by this novel approach.


Assuntos
Fontes de Energia Bioelétrica , Fontes Geradoras de Energia , Compostos de Amônio Quaternário/isolamento & purificação , Urina/química , Centrifugação , Impedância Elétrica , Eletrodos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Movimento (Física) , Termodinâmica , Eliminação de Resíduos Líquidos
11.
Br J Dermatol ; 166(1): 137-46, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21910711

RESUMO

BACKGROUND: Photodynamic therapy (PDT) with 5-aminolaevulinic acid (ALA) or its methylester [methyl-5-aminolaevulinate (MAL) or 5-amino-4-oxopentanoate] was recently ranked as first-line therapy for the treatment of actinic keratosis (AK) and is an accepted therapeutic option for the treatment of neoplastic skin diseases. BF-200 ALA (Biofrontera Bioscience GmbH, Leverkusen, Germany) is a gel formulation of ALA with nanoemulsion for the treatment of AK which overcomes previous problems of ALA instability and improves skin penetration. OBJECTIVES: To evaluate the efficacy and safety of PDT of AKs with BF-200 ALA in comparison with a registered MAL cream and with placebo. METHODS: The study was performed as a randomized, multicentre, observer-blind, placebo-controlled, interindividual trial with BF-200 ALA, a registered MAL cream and placebo in a ratio of 3:3:1. Six hundred patients, each with four to eight mild to moderate AK lesions on the face and/or the bald scalp, were enrolled in 26 study centres in Germany, Austria and Switzerland. Patients received one PDT. If residual lesions remained at 3months after treatment, PDT was repeated. RESULTS: PDT with BF-200 ALA was superior to placebo PDT with respect to patient complete clearance rate (78·2% vs. 17·1%; P<0·0001) and lesion complete clearance rate (90·4% vs. 37·1%) at 3months after the last PDT. Moreover, superiority was demonstrated over the MAL cream regarding the primary endpoint patient complete clearance (78·2% vs. 64·2%; P<0·05). Significant differences in the patient and lesion complete clearance rates and severity of treatment-related adverse events were observed for the narrow- and broad-spectrum light sources. CONCLUSIONS: BF-200 ALA is a very effective, well-tolerated new formulation for AK treatment with PDT and is superior to a registered MAL medication. Efficacies and adverse events vary greatly with the different light sources used.


Assuntos
Ácido Aminolevulínico/análogos & derivados , Ácido Aminolevulínico/administração & dosagem , Ceratose Actínica/tratamento farmacológico , Fotoquimioterapia/métodos , Administração Cutânea , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ácido Aminolevulínico/efeitos adversos , Feminino , Géis , Humanos , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Medição da Dor , Satisfação do Paciente , Fotoquimioterapia/efeitos adversos , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/efeitos adversos , Resultado do Tratamento , Adulto Jovem
12.
Opt Express ; 19(16): 15322-38, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-21934895

RESUMO

Hologram recording is studied in thermally reduced, nominally undoped lithium niobate in the time domain from 10 ns to 100 s by means of intense ns pump laser pulses (λ = 532 nm) and continuous-wave probe light (λ = 785 nm). It is shown that mixed absorption and phase gratings can be recorded within 8 ns that feature diffraction efficiencies up to 23 % with non-exponential relaxation and lifetimes in the ms-regime. The results are explained comprehensively in the frame of the optical generation of a spatial density modulation of Nb(Li)(4+/5+) antisites and the related optical features, i.e. absorption as well as index changes mutually related via the Kramers-Kronig-relation. Implications of our findings, such as the electrooptical properties of small bound Nb(Li)(4+) polarons, the optical features of Nb(Li)(4+):Nb(Nb)(4+) bipolarons, Nb(Nb)(4+) free polarons and O-hole-polarons, the impact of light polarization of pump and probe beams as well as of the polaron density are discussed.

13.
Bioresour Technol ; 102(6): 4376-82, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21277769

RESUMO

Ammonium recovery using a two chamber microbial fuel cell (MFC) was investigated at high ammonium concentration. Increasing the ammonium concentration (from 0.07 to 4 g ammonium-nitrogen/L) by addition of ammonium chloride did not affect the performance of the MFC. The obtained current densities by DC-voltammetry were higher than 6A/m(2) for both operated MFCs. Also continuous operation at lower external resistance (250 Ω) showed an increased current density (0.9A/m(2)). Effective ammonium recovery can be achieved by migrational ion flux through the cation exchange membrane to the cathode chamber, driven by the electron production from degradation of organic substrate. The charge transport was proportional to the concentration of ions. Nonetheless, a concentration gradient will influence the charge transport. Furthermore, a charge exchange process can influence the charge transport and therefore the recovery of specific ions.


Assuntos
Fontes de Energia Bioelétrica , Eletricidade , Compostos de Amônio Quaternário/análise , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Impedância Elétrica , Eletrodos , Potássio/análise , Soluções
14.
Bioresour Technol ; 101(18): 6992-7, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20434908

RESUMO

This research was aimed at studying oxidation processes, coliform inactivation effectiveness and disinfection byproducts (DBPs) associated with the disinfection of anaerobic sanitary wastewater effluent with ozone applied at doses of 5.0, 8.0 and 10.0mg O(3)L(-1) for contact times of 5, 10 and 15 min. The wastewater used in this research was generated by the wastewater treatment plant (WWTP), University of São Paulo - Brazil. The total coliform inactivation range was 2.00-4.06 log(10), and the inactivation range for Escherichia coli was 2.41-4.65 log(10). Mean chemical oxygen demand (COD) reductions were 37.6%, 48.8% and 42.4% for doses of 5.0, 8.0 and 10.0mg O(3)L(-1), respectively. Aldehyde formation varied with dosage only when the ozone dose was increased from 5.0 to 8.0mg O(3)L(-1) for acetaldehyde and from 5.0 to 8.0 and from 8.0 to 10.0mg O(3)L(-1) for glyoxal.


Assuntos
Bactérias Anaeróbias/efeitos dos fármacos , Bactérias Anaeróbias/metabolismo , Ozônio/administração & dosagem , Microbiologia da Água , Poluentes Químicos da Água/metabolismo , Purificação da Água/métodos , Água/química , Biodegradação Ambiental
15.
Br J Dermatol ; 162(2): 410-4, 2010 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19804593

RESUMO

BACKGROUND: Photodynamic therapy with a self-adhesive 5-aminolaevulinic acid (5-ALA) patch shows high efficacy rates in the treatment of mild to moderate actinic keratosis (AK) in short term trials. OBJECTIVES: The purpose of the trial was to follow up patients after successful 5-ALA patch-PDT at 3 month intervals over a total period of 12 months. Patients who had received placebo-PDT or cryosurgery served for comparison. PATIENTS/METHODS: Three months after therapy, 360 patients from two separate randomized parallel group phase III studies (one superiority trial vs. placebo-PDT, one noninferiority trial vs. cryosurgery) were suitable for the follow-up study. Patients had to show at least one successfully treated AK lesion after initial therapy. A total of 316 patients completed the follow-up. RESULTS: Twelve months after a single treatment, 5-ALA patch-PDT still proved superior to placebo-PDT and cryosurgery (P < 0.001 for all tests). On a lesion basis, efficacy rates were 63% and 79% for PDT, 63% for cryosurgery and 9% and 25% for placebo-PDT. Recurrence rates of patch-PDT proved superior to those of cryosurgery (per protocol set: P = 0.011, full analysis set: P = 0.049). While 31% of cryosurgery lesions were still hypopigmented after 1 year, the 5-ALA patch-PDT groups showed hypopigmentation in 0% (superiority trial) and 3% (noninferiority trial) of the treated lesions. CONCLUSION: Twelve months after a single 5-ALA patch-PDT the majority of lesions were still cleared with an excellent cosmetic outcome. 5-ALA patch-PDT proved to be superior to cryosurgery in the noninferiority study setting.


Assuntos
Ácido Aminolevulínico/administração & dosagem , Ceratose Actínica/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/administração & dosagem , Administração Cutânea , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Masculino , Fatores de Tempo , Resultado do Tratamento
16.
Br J Dermatol ; 160(5): 1066-74, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19222455

RESUMO

BACKGROUND: Photodynamic therapy (PDT) is increasingly used for treatment of actinic keratoses (AKs) but is a cumbersome procedure. A thin self-adhesive patch (PD P 506 A) containing 5-aminolaevulinic acid (5-ALA) was developed to facilitate PDT. OBJECTIVES: To investigate efficacy and safety of the patch in comparison with placebo-PDT (superiority design, observer-blinded; study AK 03) and standard therapy, cryosurgery (noninferiority design, open; study AK 04). METHODS: Two separate confirmatory randomized parallel-group phase III studies were set up. In total, 449 patients with up to eight mild to moderate AK study lesions located on the head were treated in 29 German study centres (study AK 03: 103 patients; study AK 04: 346 patients). RESULTS: Twelve weeks after treatment, 5-ALA patch-PDT proved to be superior to placebo-PDT (P < 0.001) and cryosurgery (P = 0.007). Efficacy rates on a lesion basis were 82% (AK 03) and 89% (AK 04) for PDT, 77% for cryosurgery and 19% (AK 03) and 29% (AK 04) for placebo-PDT. Local reactions at the treatment site occurred in almost all patients treated with 5-ALA patch-PDT or cryosurgery. Headache was the only side-effect not related to the treatment site which occurred in more than one patient. CONCLUSIONS: PD P 506 A is an innovative, easy-to-handle 5-ALA patch for PDT of mild to moderate AK lesions. Compared with current PDT procedures, pretreatment (e.g. curettage) is not needed and handling is considerably facilitated. A single PDT treatment results in efficacy rates being statistically significantly superior to placebo and cryosurgery.


Assuntos
Ácido Aminolevulínico/administração & dosagem , Ceratose Actínica/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/administração & dosagem , Administração Cutânea , Adulto , Idoso , Idoso de 80 Anos ou mais , Ácido Aminolevulínico/efeitos adversos , Criocirurgia/efeitos adversos , Formas de Dosagem , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Ceratose Actínica/cirurgia , Masculino , Pessoa de Meia-Idade , Fotoquimioterapia/efeitos adversos , Fármacos Fotossensibilizantes/efeitos adversos , Resultado do Tratamento
17.
Biotechnol Bioeng ; 101(4): 691-701, 2008 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-18814290

RESUMO

Anaerobic methanethiol (MT) degradation by mesophilic (30 degrees C) alkaliphilic (pH 10) communities was studied in a lab-scale Upflow Anaerobic Sludge Bed (UASB) reactor inoculated with a mixture of sediments from the Wadden Sea (The Netherlands), Soap Lake (Central Washington), and Russian soda lakes. MT degradation started after 32 days of incubation. During the first 252 days, complete degradation was achieved till a volumetric loading rate of 7.5 mmol MT/L/day, and sulfide, methane, and carbon dioxide were the main reaction products. Temporary inhibition of MT degradation occurred after MT peak loads and in the presence of dimethyl disulfide (DMDS), which is the autooxidation product of MT. From day 252 onwards, methanol was dosed to the reactor as co-substrate at a loading rate of 3-6 mmol/L/day to stimulate growth of methylotrophic methanogens. Methanol was completely degraded and also a complete MT degradation was achieved till a volumetric loading rate of 13 mmol MT/L/day (0.77 mmol MT/gVSS/day). However, from day 354 till the end of the experimental run (day 365), acetate was formed and MT was not completely degraded anymore, indicating that methanol-degrading homoacetogenic bacteria had partially outcompeted the methanogenic MT-degrading archea. The archeal community in the reactor sludge was analyzed by DGGE and sequencing of 16S rRNA genes. The methanogenic archea responsible for the degradation of MT in the reactor were related to Methanolobus oregonensis. A pure culture, named strain SODA, was obtained by serial dilutions in medium containing both trimethyl amine and dimethyl sulfide (DMS). Strain SODA degraded MT, DMS, trimethyl amine, and methanol. Flow sheet simulations revealed that for sufficient MT removal from liquefied petroleum gas, the extraction and biological degradation process should be operated above pH 9.


Assuntos
Biotransformação , Metano/metabolismo , Methanosarcinaceae/metabolismo , Petróleo/metabolismo , Compostos de Sulfidrila/metabolismo , Microbiologia da Água , Ácido Acético/metabolismo , Anaerobiose , Reatores Biológicos , Dióxido de Carbono , DNA Arqueal/química , DNA Arqueal/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Concentração de Íons de Hidrogênio , Metanol/metabolismo , Methanosarcinaceae/classificação , Methanosarcinaceae/isolamento & purificação , Dados de Sequência Molecular , Países Baixos , Filogenia , RNA Ribossômico 16S/genética , Federação Russa , Análise de Sequência de DNA , Sulfetos/metabolismo , Temperatura , Washington
18.
Wound Repair Regen ; 15(3): 308-15, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17537117

RESUMO

In a multicenter trial, the effect of a commercially available combination of autologous keratinocytes (3-6 x 10(6)/mL) with fibrin sealant (Tissucol Duo S Immuno, Baxter Hyland Immuno) on the healing of recalcitrant venous leg ulcers (duration >3 months) was compared with standard care. The primary endpoint was time to healing, and the secondary endpoint was number of healed ulcers in both groups. Both groups received compression therapy with short-stretch bandages. Forty-four (38.3%) of the 116 patients who had BioSeed-S treatment achieved complete healing of the target ulcer compared with 24 (22.4%) of 109 patients who received standard treatment. The advantage for treatment with BioSeed-S over standard treatment was statistically significant (chi-square test: p=0.0106). Time to complete healing of ulcers: the log-rank test for equality over strata revealed a superiority of treatment with BioSeed-S+compression (median: 176 days) over compression+standard care (median >201 days) (p<0.0001). This study, to date the largest multicenter study with autologous keratinocytes, provides evidence for its efficacy in the treatment of patients with therapy-resistant chronic venous leg ulcers.


Assuntos
Adesivo Tecidual de Fibrina/uso terapêutico , Queratinócitos/transplante , Úlcera da Perna/terapia , Úlcera Varicosa/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Bandagens , Distribuição de Qui-Quadrado , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estatísticas não Paramétricas , Transplante Autólogo , Resultado do Tratamento
19.
Artigo em Inglês | MEDLINE | ID: mdl-18204744

RESUMO

BACKGROUND: Sublingual immunotherapy (SLIT) is a recognized and safe treatment for allergic rhinitis and conjunctivitis. The aim was to evaluate the efficacy and safety of tablets for grass and rye pollen- induced rhinitis and conjunctivitis. METHODS: A double-blind, randomized, placebo-controlled trial was carried out over 9 months. 105 patients received a standardized grass/rye mix extract or a placebo using sublingual drops during the build-up phase. Drops were replaced by sublingual tablets during the maintenance phase (300 IR/daily). RESULTS: In patients that received active treatment, a significantly lower total symptom score (rhinitis and conjunctivitis) compared to the placebo group was observed (p = 0.038). The investigators' assessment revealed a significant improvement in favor of the active treatment group (p = 0.018). Skin reactivity to grass and rye pollen was significantly reduced in the active treatment group (p < 0.05). No statistical difference was observed between the two groups for serum-specific IgG4 levels. Side effects were local and mild, and no severe systemic reactions were reported. CONCLUSION: This study indicates that tablet-based sublingual immunotherapy was safe and significantly improved grass/rye pollen-induced rhinoconjunctivitis symptoms. It was also associated with a significant inhibition of the immediate skin response.


Assuntos
Conjuntivite Alérgica/terapia , Dessensibilização Imunológica , Rinite Alérgica Sazonal/terapia , Administração Sublingual , Adolescente , Adulto , Alérgenos/imunologia , Estudos de Casos e Controles , Conjuntivite Alérgica/imunologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pólen/imunologia , Rinite Alérgica Sazonal/imunologia
20.
Water Sci Technol ; 47(10): 17-24, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12862212

RESUMO

Ozonation can be a suitable technique for the pre-treatment of wastewater containing low concentrations of toxic or non-biodegradable compounds that cannot be treated with satisfactory results when only the traditional, less expensive biological techniques are applied. In this case, the oxidation process has to be made as efficient as possible, in order to reduce the coats of ozone addition and use. An efficient oxidation process with ozone can be obtained by focusing the oxidation with ozone selectively on the direct oxidation of toxic pollutants and to minimize ozone losses due to the decay of ozone in water. Supported by data of the rate constants of the reactions involved, a mathematical model was developed. It quantifies the ozone consumption by the process, and the share of ozone consumption by undesired side reactions, in several different reactor systems. Results obtained with this model indicate that a plug flow reactor (PFR) will be the most efficient design for the oxidation reactor. As an alternative, the cascaded tank reactor system (CTR), in which the ozone feed may be realized with less practical problems, might be considered. The traditional continuous flow stirred tank reactor (CFSTR) is shown to be the least efficient system.


Assuntos
Modelos Teóricos , Oxidantes Fotoquímicos/química , Ozônio/química , Poluição da Água/prevenção & controle , Purificação da Água/métodos , Conservação de Recursos Energéticos , Arquitetura de Instituições de Saúde , Oxirredução , Poluentes Químicos da Água/toxicidade
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