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1.
Br J Surg ; 110(9): 1180-1188, 2023 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-37311694

RESUMEN

BACKGROUND: The aim of this study was to compare the clinical outcomes between breast cancer patients who underwent axillary lymph node dissection with postoperative management using a polyethylene glycol-coated patch versus axillary drainage. The direct costs associated with both postoperative management strategies were also evaluated. METHODS: This was a multicentre RCT in women with breast cancer who underwent axillary lymph node dissection (ClinicalTrials.gov identifier: NCT04487561). Patients were randomly assigned (1 : 1) to receive either drainage or a polyethylene glycol-coated patch as postoperative management. The primary endpoints were the need for an emergency department visit for any event related to the surgery and the rate of seroma development. RESULTS: A total of 227 patients were included , 115 in the patch group (50.7 per cent) and 112 (29.4 per cent ) in the drainage group. The incidence of emergency department visits was significantly greater for patients with drainage versus a polyethylene glycol-coated patch (incidence rate difference 26.1 per cent, 95 per cent c.i. 14.5 to 37.7 per cent; P < 0.001). Conversely, the seroma rate was significantly higher in the polyethylene glycol-coated patch group (incidence rate difference 22.8 per cent, 95 per cent c.i. 6.7 to 38.9 per cent; P < 0.0055). Compared with drainage, using a polyethylene glycol-coated patch resulted in cost savings of €100.41 per patient. An incremental cost-effectiveness ratio analysis found that drainage was associated with an incremental cost-effectiveness ratio of €7594.4 for no need for hospital admission and €491.7 for no need for an emergency department visit. CONCLUSION: Compared with patients who received drainage after axillary lymph node dissection, the use of a polyethylene glycol-coated patch resulted in a higher rate of seroma, but a lower number of postoperative outpatient or emergency department visits and thus a reduction in overall costs.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/patología , Seroma/epidemiología , Seroma/etiología , Seroma/cirugía , Escisión del Ganglio Linfático/métodos , Drenaje/métodos , Hospitalización , Axila/patología
2.
Int Microbiol ; 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38010565

RESUMEN

Antibiotics in wastewater treatment plants can alter the physiological activity and the structure of microbial communities through toxic and inhibitory effects. Physiological adaptation, kinetic, and population dynamics behavior of a nitrifying sludge was evaluated in a sequential batch reactor (SBR) fed with 14.4 mg/L of ampicillin (AMP). The addition of AMP did not affect ammonium consumption (100 mg NH4+-N/L) but provoked nitrite accumulation (0.90 mg NO2--N formed/mg NH4+-N consumed) and an inhibition of up to 67% on the nitrite oxidizing process. After 30 cycles under AMP feeding, the sludge recovered its nitrite oxidizing activity with a high nitrate yield (YNO3-) of 0.87 ± 0.10 mg NO3--N formed/mg NH4+-N consumed, carrying out again a stable and complete nitrifying process. Increases in specific rate of nitrate production (qNO3-) showed the physiological adaptation of the nitrite oxidizing bacteria to AMP inhibition. Ampicillin was totally removed since the first cycle of addition. Exposure to AMP had effects on the abundance of bacterial populations, promoting adaptation of the nitrifying sludge to the presence of the antibiotic and its consumption. Nitrosomonas and Nitrosospira always remained within the dominant genera, keeping the ammonium oxidizing process stable while an increase in Nitrospira abundance was observed, recovering the stability of the nitrite oxidizing process. Burkholderia, Pseudomonas, and Thauera might be some of the heterotrophic bacteria involved in AMP consumption.

3.
Liver Transpl ; 28(6): 1039-1050, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34919762

RESUMEN

Long-term humoral immunity and its protective role in liver transplantation (LT) patients have not been elucidated. We performed a prospective multicenter study to assess the persistence of immunoglobulin G (IgG) antibodies in LT recipients 12 months after coronavirus disease 2019 (COVID-19). A total of 65 LT recipients were matched with 65 nontransplanted patients by a propensity score including variables with recognized impact on COVID-19. LT recipients showed a lower prevalence of anti-nucleocapsid (27.7% versus 49.2%; P = 0.02) and anti-spike IgG antibodies (88.2% versus 100.0%; P = 0.02) at 12 months. Lower index values of anti-nucleocapsid IgG antibodies were also observed in transplantation patients 1 year after COVID-19 (median, 0.49 [interquartile range, 0.15-1.40] versus 1.36 [interquartile range, 0.53-2.91]; P < 0.001). Vaccinated LT recipients showed higher antibody levels compared with unvaccinated patients (P < 0.001); antibody levels reached after vaccination were comparable to those observed in nontransplanted individuals (P = 0.70). In LT patients, a longer interval since transplantation (odds ratio, 1.10; 95% confidence interval, 1.01-1.20) was independently associated with persistence of anti-nucleocapsid IgG antibodies 1 year after infection. In conclusion, compared with nontransplanted patients, LT recipients show a lower long-term persistence of anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies. However, SARS-CoV-2 vaccination after COVID-19 in LT patients achieves a significant increase in antibody levels, comparable to that of nontransplanted patients.


Asunto(s)
COVID-19 , Inmunidad Humoral , Trasplante de Hígado , Anticuerpos Antivirales/sangre , COVID-19/inmunología , Vacunas contra la COVID-19 , Humanos , Inmunoglobulina G/sangre , Estudios Prospectivos , SARS-CoV-2
4.
Am J Transplant ; 21(8): 2876-2884, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33835707

RESUMEN

The protective capacity and duration of humoral immunity after SARS-CoV-2 infection are not yet understood in solid organ transplant recipients. A prospective multicenter study was performed to evaluate the persistence of anti-nucleocapsid IgG antibodies in liver transplant recipients 6 months after coronavirus disease 2019 (COVID-19) resolution. A total of 71 liver transplant recipients were matched with 71 immunocompetent controls by a propensity score including variables with a well-known prognostic impact in COVID-19. Paired case-control serological data were also available in 62 liver transplant patients and 62 controls at month 3 after COVID-19. Liver transplant recipients showed a lower incidence of anti-nucleocapsid IgG antibodies at 3 months (77.4% vs. 100%, p < .001) and at 6 months (63.4% vs. 90.1%, p < .001). Lower levels of antibodies were also observed in liver transplant patients at 3 (p = .001) and 6 months (p < .001) after COVID-19. In transplant patients, female gender (OR = 13.49, 95% CI: 2.17-83.8), a longer interval since transplantation (OR = 1.19, 95% CI: 1.03-1.36), and therapy with renin-angiotensin-aldosterone system inhibitors (OR = 7.11, 95% CI: 1.47-34.50) were independently associated with persistence of antibodies beyond 6 months after COVID-19. Therefore, as compared with immunocompetent patients, liver transplant recipients show a lower prevalence of anti-SARS-CoV-2 antibodies and more pronounced antibody levels decline.


Asunto(s)
COVID-19 , Trasplante de Hígado , Femenino , Humanos , Inmunidad Humoral , Estudios Prospectivos , SARS-CoV-2 , Receptores de Trasplantes
5.
World J Microbiol Biotechnol ; 36(2): 21, 2020 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-31955272

RESUMEN

Ampicillin is a widely used ß-lactam antibiotic that has been detected in various effluents and can alter biological processes used in wastewater treatment such as nitrification. Physiological and kinetic behaviour of a nitrifying consortium in the presence of ampicillin (AMP) (10, 25, and 50 mg/L) was evaluated in batch cultures. Under the experimental conditions (320 ± 8 mg bacterial protein/L, C/N = 2.4, 24 h), the nitrifying behaviour was very similar among the controls without AMP and the assays with antibiotic, as there was no AMP effect on efficiency (ENH4+ = 99.7 ± 4.2%), yields (YNO2- = 0, YNO3- = 1.0 ± 0.1 mg N/mg NH4+-N consumed), neither specific rates of NH4+ oxidation and NO3- formation. Therefore, nitrifying bacteria were insensitive to AMP presence. At all assayed concentrations, after 24 h, 70.5 ± 3.7% of AMP was removed from the cultures through abiotic (16.0-16.5%), biosorption (23.2-47.0%), and biotransformation (10.0-29.8%) processes. With the increase in the initial AMP concentration, a greater participation of the biotransformation process, associated to an increase in the specific AMP consumption rate was attained. The sludge was able to completely oxidize NH4+ to NO3- by nitrification and eliminate AMP biologically, but without reaching its full mineralization.


Asunto(s)
Ampicilina/análisis , Bacterias/crecimiento & desarrollo , Técnicas de Cultivo Celular por Lotes/métodos , Compuestos de Amonio/análisis , Bacterias/metabolismo , Biodegradación Ambiental , Reactores Biológicos/microbiología , Biotransformación , Nitrificación
6.
Environ Technol ; 36(13-16): 1776-84, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25666400

RESUMEN

The aim of this study was to contribute to the knowledge on the dynamic of the microbial community involved in anaerobic degradation of different concentrations of 2-chlorophenol (2CP, from 28 to 196 mg 2CP-C/L) and a mixture of 2CP and phenol (from 28 to 196 mg phenol-C/L) and its relationship with the respiratory process in two anaerobic sequencing batch reactors (ASBR). The dynamic of the microbial community was evaluated by denaturant gradient gel electrophoresis (DGGE) and ecological indices (S and J indices). The respiratory process was evaluated by means of substrate consumption efficiency, biogas yield, and specific consumption rates as response variables. The high consumption efficiency (90%) and the constant biogas yields obtained at concentrations up to 140 mg C/L may be related with the evenness of microbial populations (J index=0.97±0.2) present in both reactors. Pseudomonas genus was present in all concentrations tested, suggesting a possible relationship with the dehalogenation observed in both reactors. The decrease in specific consumption rate and biogas yield as well as the accumulation of phenol and volatile fatty acids observed in both reactors at 196 mg 2CP-C/L might be associated with the disappearance of the bands related to Caulobacter and Bacillus. At these conditions, the disappearance of fermentative or acetogenic bacteria resulted in reduction of substrates required to carry out methanogenesis, which eventually might cause the declination in methanogenic populations present in the reactors.


Asunto(s)
Bacterias Anaerobias/aislamiento & purificación , Bacterias Anaerobias/fisiología , Reactores Biológicos/microbiología , Clorofenoles/metabolismo , Clorofenoles/farmacología , Interacciones Microbianas/fisiología , Bacterias Anaerobias/efectos de los fármacos , Clorofenoles/aislamiento & purificación , Metanol/metabolismo , Interacciones Microbianas/efectos de los fármacos , Oxígeno/metabolismo , Contaminantes Químicos del Agua/aislamiento & purificación , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/farmacología , Purificación del Agua/métodos
7.
J Environ Sci (China) ; 26(9): 1885-93, 2014 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-25193839

RESUMEN

The ability of a nitrifying sludge to oxidize p-cresol was evaluated in a sequential batch reactor (SBR). p-Cresol was first transformed to p-hydroxybenzaldehyde and p-hydroxybenzoate, which were later mineralized. The specific rates of p-cresol consumption increased throughout the cycles. The bacterial population dynamics were monitored by using denaturing gradient gel electrophoresis (DGGE) and sequencing of DGGE fragments. The ability of the sludge to consume p-cresol and intermediates might be related to the presence of species such as Variovorax paradoxus and Thauera mechernichensis. p-Cresol (25 to 200mgC/L) did not affect the nitrifying SBR performance (ammonium consumption efficiency and nitrate production yield were close to 100% and 1, respectively). This may be related to the high stability observed in the nitrifying communities. It was shown that a nitrifying SBR may be a good alternative to eliminate simultaneously ammonium and p-cresol, maintaining stable the respiratory process as the bacterial community.


Asunto(s)
Reactores Biológicos/microbiología , Cresoles/química , Consorcios Microbianos , Nitrificación , Electroforesis en Gel de Gradiente Desnaturalizante , Oxidación-Reducción , Análisis de Secuencia de ADN
8.
Polymers (Basel) ; 16(11)2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38891469

RESUMEN

This paper reports the successful development and application of an efficient method for quantifying Pb2+ in aqueous samples using a smartphone-based colorimetric device with an imprinted polymer (IIP). The IIP was synthesized by modifying the previous study; using rhodizonate, 2-acrylamido-2-methylpropane sulfonic acid (AMPS), N,N'-methylenebisacrylamide (MBA), and potassium persulfate (KPS). The polymers were then characterized. An absorption study was performed to determine the optimal conditions for the smartphone-based colorimetric device processing. The device consists of a black box (10 × 10 × 10 cm), which was designed to ensure repeatability of the image acquisition. The methodology involved the use of a smartphone camera to capture images of IIP previously exposed at Pb2+ solutions with various concentrations, and color channel values were calculated (RGB, YMK HSVI). PLS multivariate regression was performed, and the optimum working range (0-10 mg L-1) was determined using seven principal components with a detection limit (LOD) of 0.215 mg L-1 and R2 = 0.998. The applicability of a colorimetric sensor in real samples showed a coefficient of variation (% RSD) of less than 9%, and inductively coupled plasma mass spectrometry (ICP-MS) was applied as the reference method. These results confirmed that the quantitation smartphone-based colorimetric sensor is a suitable analytical tool for reliable on-site Pb2+ monitoring.

9.
Biodegradation ; 24(3): 377-85, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23054182

RESUMEN

The kinetic behavior, oxidizing ability and tolerance to m-cresol of a nitrifying sludge exposed to different initial concentrations of m-cresol (0-150 mg C L(-1)) were evaluated in a sequencing batch reactor fed with 50 mg NH4 (+)-N L(-1) and operated during 4 months. Complete removal of ammonium and m-cresol was achieved independently of the initial concentration of aromatic compound in all the assays. Up to 25 mg m-cresol-C L(-1) (C/N ratio of 0.5), the nitrifying yield (Y-NO3 (-)) was 0.86 ± 0.05, indicating that the nitrate was the main product of the process; no biomass growth was detected. From 50 to 150 mg m-cresol-C L(-1) (1.0 ≤ C/N ≤ 3.0), simultaneous microbial growth and partial ammonium-to-nitrate conversion were obtained, reaching a maximum microbial total protein concentration of 0.763 g L(-1) (247 % of its initial value) and the lowest Y-NO3 (-) 0.53 ± 0.01 at 150 mg m-cresol-C L(-1). m-Cresol induced a significant decrease in the values of both specific rates of ammonium and nitrite oxidation, being the ammonium oxidation pathway the mainly inhibited. The nitrifying sludge was able to completely oxidize up to 150 mg m-cresol-C L(-1) by SBR cycle, reaching a maximum specific removal rate of 6.45 g m-cresol g(-1) microbial protein-N h(-1). The number of SBR cycles allowed a metabolic adaptation of the nitrifying consortium since nitrification inhibition decreased and faster oxidation of m-cresol took place throughout the cycles.


Asunto(s)
Reactores Biológicos , Cresoles/aislamiento & purificación , Compuestos de Amonio Cuaternario/aislamiento & purificación , Biodegradación Ambiental , Cinética , Nitrificación , Oxidación-Reducción , Aguas del Alcantarillado
10.
3 Biotech ; 13(1): 17, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36568497

RESUMEN

Production, preservation and recovery of sludge with stabilized nitrifying activity over long time can be difficult. Information on the ability of nitrifying sludge to regain its nitrifying activity after long-term storage is still scarce. In this work, the physiological and kinetic changes during the reactivation and stabilization of a nitrifying sludge previously exposed to ampicillin (AMP) were evaluated in a sequential batch reactor (SBR) after its long-term storage (1 year) at 4 °C. After storage, both ammonium and nitrite oxidizing processes were slow, being nitrite oxidation the most affected step. During the reactivation stage (cycles 1-6), physiological and kinetic activity of the nitrifying sludge improved through the operating cycles, in both its ammonium oxidizing and nitrite oxidizing processes. At the end of the reactivation stage, complete nitrifying activity was achieved in 10 h, reaching ammonium consumption efficiencies (ENH4 +) close to 100% and nitrate yields (YNO3 -) of 0.98 mg NO3 --N/mg NH4 +-N consumed without nitrite accumulation. During the stabilization stage (cycles 7-17), results indicated that the sludge could maintain a steady-state respiratory process with restoration percentages of 100% for nitrifying specific rates (qNH4 + and qNO3 -) with respect to their values obtained before storage. Furthermore, during the addition of 15 mg AMP/L (cycles 18-21), the sludge preserved its metabolic capacity to biodegrade 90% of AMP in 2 h. Therefore, long-term storage of nitrifying sludge could be used to preserve nitrifying inocula as bioseeds for bioremediation and bioaugmentation strategies.

11.
Water Sci Technol ; 65(10): 1721-8, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22546784

RESUMEN

The aim of this study is to contribute to the knowledge about anaerobic digestion of 2-chlorophenol (2CP) in an anaerobic sequencing batch reactor (ASBR). Two reactors were set up (ASBR(A) and ASBR(B)). The ASBR(A) was fed with 2-chlorophenol (28-196 mg 2CP-C/L) and no other exogenous electron donor. The ASBR(B) was fed with a mixture of 2CP (28-196 mg 2CP-C/L) and phenol (28-196 mg phenol-C/L) as an electron donor. The process evaluation was conducted by three means: first by substrate consumption efficiency (E(2CP)), second, by biogas yield (Y(biogas-C/2CP-C)) and third, by the specific consumption rates (q(2CP)) as response variables. The 2CP consumption efficiency (90 ± 0.4%) was not influenced by the increase in the concentrations tested. In both reactors ASBR(A) and ASBR(B), both concentration as well as speed increased. Concentration increased from 28 to 114 mg 2CP-C/L. The specific consumption rate (q(2CP)) values were fivefold higher. However, a decrease of 37% was observed at 140 mg 2CP-C/L and one of 72% at 196 mg 2CP-C/L. The biogas yields (0.80 ± 0.06) remained stable in both reactors. In both reactors the biogas yield decreased to 78 ± 3% at 196 mg 2CP-C/L. We might assume this decrease was due to the accumulation of VFA. Finally, poor sludge settleability was determined only in the SBR(B) reactor at 140 and 196 mg 2CP-C/L. An increase was observed in both SVI ≤ 140 ± 5 mL/g and over exopolymeric protein ≤120 mg EP/L.


Asunto(s)
Reactores Biológicos/microbiología , Clorofenoles/química , Aguas del Alcantarillado/microbiología , Eliminación de Residuos Líquidos/métodos , Anaerobiosis , Biodegradación Ambiental , Clorofenoles/metabolismo , México
12.
Environ Technol ; 33(10-12): 1375-82, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22856312

RESUMEN

Chlorophenols are widely distributed in the environment. Various strategies have been used to improve their biological elimination under anaerobic conditions; however, such information is still scarce. The aim of this study was to evaluate in batch assays the consumption of 2-chlorophenol (2-CP) by a denitrifying sludge and the influence of acetate or phenol as co-substrates in the 2-CP consumption. It was observed that phenol (69 and 92 mg phenol-C L(-1)) and acetate (60 and 108 mg acetate-C L(-1)) enhanced 2-CP consumption by the denitrifying sludge, increasing both the efficiency (up to 100%) and specific rate of 2-CP consumption. When phenol was added at 92 mg C L(-1), the specific consumption rate of 2-CP increased 2.6 times with respect to the control lacking co-substrates, whereas with acetate (108 mgC L(-1)) the increase was 9.0 times. Acetate appeared to be a better co-substrate for 2-CP consumption, obtaining a specific consumption rate of 2.48 +/- 0.14 mg 2-CP-C g(-1) VSS d(-1) at 108 mg acetate-C L(-1). The mass balance analysis indicated that the denitrifying sludge was able to simultaneously mineralize 2-CP, phenol or acetate (E2-CP, E(Phenol), and E(Acetate) close to 100% [E = consumption efficiency], Y(HCO3-) of 0.90 +/- 0.10 [Y = yield]) and reduce nitrate to nitrogen gas (E(NO3-) of 100% and Y(N2) of 0.96 +/- 0.02). It was shown that the addition of co-substrates as phenol or acetate could be a good alternative for improving the elimination of chlorophenols from wastewaters by denitrifying sludges.


Asunto(s)
Acetatos/metabolismo , Clorofenoles/metabolismo , Contaminantes Ambientales/metabolismo , Fenol/metabolismo , Aguas del Alcantarillado , Desnitrificación
13.
Chemosphere ; 270: 129461, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33412355

RESUMEN

Benzotriazole (BT) is a corrosion inhibitor widely distributed in aquatic environments. Little is known about the cometabolic capacity of stabilized nitrifying sludge to biotransform BT. The contribution of the nitrification process in the simultaneous oxidation of ammonium and biotransformation of BT (5 mg/L) was evaluated in 49 d batch cultures inoculated with a sludge produced in steady-state nitrification. The nitrifying sludge could consume BT in the obligate presence of ammonium. A higher cometabolic biotransformation capacity was obtained by increasing the initial ammonium concentration (100-300 mg N/L), reaching 2.3- and 5.8-fold increases for efficiency and specific rate of BT removal. At 300 mg NH4+-N/L, the sludge biotransform 40.8% of BT and 77.6% of ammonium which was completely oxidized into nitrate. In assays with allylthiourea added as specific inhibitor of ammonium monooxygenase (AMO), it was shown that the totality of BT cometabolic biotransformation was associated with the AMO activity. The addition of acetate did not favor heterotrophic biotransformation of BT. BT provoked inhibitory effects on nitrification. This is the first study showing the role of ammonium oxidizing bacteria in the cometabolic biotransformation of BT and their potential use for cometabolism application in treatment of wastewater contaminated with ammonium and BT.


Asunto(s)
Técnicas de Cultivo Celular por Lotes , Reactores Biológicos , Biotransformación , Nitrificación , Aguas del Alcantarillado , Triazoles
14.
Waste Manag ; 120: 76-84, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33285376

RESUMEN

A two-stage bioreactor operated under anoxic denitrifying conditions was evaluated for desulfurization of synthetic biogas laden with H2S concentrations between 2500 and 10,000 ppmv. H2S removal efficiencies higher than 95% were achieved for H2S loads ranging from 16.2 to 51.9 gS mliquid-3h-1. Average H2S oxidation performance (fraction of S-SO42- produced per gram of S-H2S absorbed) ranged between 8.2 ± 1.2 and 18.7 ± 5.3% under continuous liquid operation. Nitrogen mass balance showed that only 2-6% of the N-NO3- consumed was directed to biomass growth and the rest was directed to denitrification. Significant changes in the bacterial community composition did not hinder the H2S removal efficiency. The bioreactor configuration proposed avoided clogging issues due to elemental sulfur accumulation as commonly occurs in packed bed bioreactors devoted to H2S-rich biogas desulfurization.


Asunto(s)
Biocombustibles , Sulfuro de Hidrógeno , Reactores Biológicos , Desnitrificación , Nitratos , Azufre
15.
Water Environ Res ; 93(4): 636-644, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33073480

RESUMEN

Anammox is a cost-effective and sustainable process for nitrogen removal; however, the production of a physiologically stable inoculum is a critical point in the start-up process. In this work, estuarine sediments were used as incubation seeds to obtain cultures with stable anammox activity. Assays were performed in batch cultures fed with stoichiometric amounts of ammonium and nitrite, analyzing physiological response variables and the microbial community. Estuarine sediments showed a stable anammox process after 90 days, consuming ammonium and nitrite simultaneously with concomitant generation of N2 and nitrate in stoichiometric amounts. In kinetic assays, substrates were fully consumed after 210 hr, exhibiting N2 and nitrate yields of 0.85 and 0.10, respectively. The microbial community analysis using PCR-DGGE indicated the presence of uncultured anammox bacteria and members of the genus Candidatus Jettenia. The results evidenced the achievement of anammox cultures, although their start-up and kinetic characteristics were less favorable than those recorded in man-made systems. PRACTITIONER POINTS: Estuarine sediments were used as incubation seeds to obtain cultures with stable anammox activity. The sediments were fed with stoichiometric amounts of ammonium and nitrite, analyzing the physiological response variables and the microbial community. Sediments showed a stable anammox process after 90 days, converting the substrates into N2 and nitrate according to stoichiometry. Anammox cultures were achieved although their start-up and kinetic characteristics were less favorable than those recorded in man-made systems. Microbial community analysis using PCR-DGGE indicated the presence of uncultured anaerobic ammonia-oxidizing bacterium and members of genus Candidatus Jettenia.


Asunto(s)
Compuestos de Amonio , Nitrógeno , Anaerobiosis , Bacterias/genética , Reactores Biológicos , Humanos , Nitritos , Oxidación-Reducción
16.
Water Sci Technol ; 62(8): 1791-8, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20962394

RESUMEN

The aim of this study is to contribute to the knowledge about 2-Chlorophenol (2CP) mineralization and methanization in batch culture. This work was focused on evaluating the effect of: (i) the use of sludge with different periods of previous contact to 2CP, (ii) the electron donor addition in stoichiometric relation with 2CP and (iii) the presence of different initial oxygen concentrations. When compared with the control, 50 and 80 days of previous contact to 2CP resulted in a lag phase reduction of 57% and an increase in 2CP specific consumption rate (q(2CP)) of 114%. These results were obtained with no addition of an external electron donor. When acetate was used as an electron donor its consumption resulted independently of 2CP consumption. No lag phase and increase of 46% in q(2CP) was observed when phenol was used as an electron donor. In the third part when sludge without previous contact to 2CP was used, it was found that consumption efficiency (E(2CP)) and q(2CP) values did not increase in the presence of different oxygen concentrations. However, at the highest oxygen concentration, CH(4) yield (Y(CH(4))(-C/2CP-C)) and phenol yield (Y(phenol-C/2CP-C)) values decreased, while CO(2) yield value (Y(CO(2))(-C/2CP-C)) increased with regard to the methanogenic control. The use of sludge previously exposed to both 2CP and O(2) resulted in an increase in q(2CP) of 73%. However, among the different oxygen concentrations, no significant difference in E(2CP) or q(2CP) values was observed when compared to the control without oxygen. Therefore, previous contact to 2CP resulted in being a key factor for improving 2CP mineralization and methanization in batch culture.


Asunto(s)
Clorofenoles/análisis , Metano/análisis , Minerales/análisis , Aguas del Alcantarillado , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Anaerobiosis , Reactores Biológicos/microbiología , Clorofenoles/química , Transporte de Electrón , Minerales/química , Oxígeno/química , Aguas del Alcantarillado/química , Aguas del Alcantarillado/microbiología , Contaminantes Químicos del Agua/química , Purificación del Agua/instrumentación
17.
Chemosphere ; 253: 126637, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32278910

RESUMEN

A kinetic study was carried out in a sequencing batch reactor (SBR) (125 mg NH4+-N/L) inoculated with a physiologically stable nitrifying sludge not previously acclimated to sulfur compounds and fed at different initial sulfide concentrations (2.5-20.0 mg HS--S/L). Up to 10.0 mg HS--S/L, the nitrifying process kept stable and complete, reaching an ammonium consumption efficiency (ENH4+) of 100% and a nitrate yield (YNO3-) of 0.95 ± 0.03 mg NO3--N/mg NH4+-N consumed. At 15.0 and 20.0 mg HS--S/L, after an initial alteration in the nitrite oxidizing process, the YNO2- was decreasing throughout the cycles and the YNO3- increasing, obtaining in the last cycle at 20.0 mg HS--S/L, an ENH4+ of 100%, a YNO2- of zero, and a YNO3- of 0.80 mg NO3--N/mg NH4+-N consumed. At the end of the period at 20.0 mg HS--S/L, the specific rates of ammonium consumption and nitrate formation were 15 and 55% lower than their respective values in the control period without sulfide addition, showing that the sludge had a better metabolic adaptation for ammonium oxidizing activity than for nitrite oxidizing activity. The sludge acquired a higher sulfide oxidation capacity along the cycles. Bacterial population dynamics assessment indicated that the ammonium oxidizing bacteria (AOB) community was more diverse and stable than the nitrite oxidizing bacteria (NOB) community. The use of consortia with a previously stabilized nitrifying activity in SBR may constitute an alternative for eliminating simultaneously ammonium by nitrification and sulfide by sulfide oxidation and be implemented for the treatment of wastewater with ammonium and sulfide.


Asunto(s)
Compuestos de Amonio/metabolismo , Sulfuros/metabolismo , Eliminación de Residuos Líquidos/métodos , Bacterias/metabolismo , Reactores Biológicos/microbiología , Cinética , Nitratos/metabolismo , Nitrificación , Nitritos/metabolismo , Oxidación-Reducción , Dinámica Poblacional , Aguas del Alcantarillado/microbiología , Compuestos de Azufre/metabolismo , Aguas Residuales
18.
Transplant Proc ; 52(2): 556-558, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32035673

RESUMEN

BACKGROUND: Calcineurin inhibitors have been implicated in acute and chronic kidney disease after liver transplant (LT). Everolimus (EVR) is a mammalian target of rapamycin inhibitor efficacious in preventing acute cellular rejection while preserving renal function among LT recipients. We evaluated the benefits on renal function of EVR immunosuppression in LT recipients. METHODS: We performed a retrospective and observational study in 477 LT recipients in Virgen de las Nieves Hospital from 2002 to 2019 on the use of EVR with tacrolimus minimization or withdrawal in LT recipients with renal dysfunction. The study included 100 patients starting EVR (20.96%); in 66 (66%) the indication was renal dysfunction. The change in renal function was assessed by estimated glomerular filtration rate. Statistical analyses were performed using SPSS 17.0 software (IBM, Munich, Germany). RESULTS: Fifty 8 patients received mycophenolate mofetil (87.8%), and tacrolimus therapy was stopped in 27 patients (40.9%). Induction therapy with basiliximab was administered in 41 patients (62.12%). There was significant difference between estimated glomerular filtration rate at the time of starting EVR and the first month at last follow-up (49.42 mL/min/1.73 m2 vs 75.27 mL/min/1.73 m2; P < .001) and at end of follow-up (24 months) (49.42 mL/min/1.73 m2 vs 64.32 mL/min/1.73 m2; P = .001). The rate of incidence of adverse events was 48.48% (32/66). Seven patients died during follow-up (10.6%), but there were no EVR-related deaths. Eleven patients (16.6%) developed biopsy-proven acute rejection. CONCLUSION: This study showed that EVR is associated with a beneficial effect on glomerular filtration rate in both the short and long term in LT recipients.


Asunto(s)
Everolimus/administración & dosificación , Inmunosupresores/administración & dosificación , Trasplante de Hígado/efectos adversos , Complicaciones Posoperatorias/tratamiento farmacológico , Insuficiencia Renal Crónica/tratamiento farmacológico , Adulto , Basiliximab/administración & dosificación , Biopsia , Inhibidores de la Calcineurina/efectos adversos , Quimioterapia Combinada , Femenino , Tasa de Filtración Glomerular/efectos de los fármacos , Rechazo de Injerto/prevención & control , Supervivencia de Injerto/efectos de los fármacos , Humanos , Terapia de Inmunosupresión/métodos , Masculino , Persona de Mediana Edad , Ácido Micofenólico/administración & dosificación , Complicaciones Posoperatorias/inducido químicamente , Insuficiencia Renal Crónica/inducido químicamente , Estudios Retrospectivos , Sirolimus/administración & dosificación , Tacrolimus/administración & dosificación
19.
Transplant Proc ; 52(2): 553-555, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32035682

RESUMEN

BACKGROUND: Calcineurin inhibitors are associated with the development of de novo tumors and increased recurrence of hepatocellular carcinoma after liver transplant. It has been suggested that mammalian target of rapamycin inhibitors (everolimus [EVR]) may improve prognosis. We analyzed our experience on the use of EVR in malignant neoplasms in liver transplantation. METHODS: We performed a retrospective descriptive analysis of 477 transplants performed between 2002 and 2019 at Virgen de las Nieves Hospital. A total of 100 patients received EVR; 23 transplants were because of tumor disease (23%), with de novo tumor in 12 patients and hepatocarcinoma in 11. The statistical study was carried out using the statistical program SPSS 17.0 software. RESULTS: The study included 18 male patients (78.3%) and 5 female patients (21.7%) with an average age of 59.67 years. The most common indications of liver transplant have been alcoholic cirrhosis in 39% and hepatitis C virus cirrhosis in 21.7%. De novo tumors were lung neoplasm in 4 patients (33.3%), lymphoma in 2 patients(16.7%), oropharynx in 2 patients (16.7%), skin tumors in 2 patients (16.7%), and a kidney tumor (8.3%) in 1 patient. As for hepatocellular carcinoma, 8 patients met Milan criteria on the explant (61.5%). Tacrolimus was discontinued in all cases. The average onset time of post-transplant EVR was 2231.42 days in the de novo neoplasms and 307.45 days in those receiving transplants because of hepatocellular carcinoma (P = .05). We observed 5 deaths (21.7%). CONCLUSION: Although the beneficial long-term role of EVR in liver transplant recipients with tumor disease is not demonstrated, it is used by most transplant units, both in de novo neoplasms and those receiving transplants because of hepatocellular carcinoma.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma Hepatocelular/terapia , Everolimus/uso terapéutico , Neoplasias Hepáticas/terapia , Recurrencia Local de Neoplasia/tratamiento farmacológico , Complicaciones Posoperatorias/tratamiento farmacológico , Adulto , Inhibidores de la Calcineurina/efectos adversos , Carcinoma Hepatocelular/patología , Femenino , Humanos , Neoplasias Hepáticas/patología , Trasplante de Hígado/efectos adversos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/etiología , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Resultado del Tratamiento
20.
Arch Environ Contam Toxicol ; 57(4): 679-87, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19387525

RESUMEN

Toluene is usually present in the environment as a contaminant along with other carbon sources which may influence its removal. In this work we studied the effect of a readily consumable carbon source such as acetate on toluene mineralization under denitrifying conditions. Continuous and batch cultures with stabilized denitrifying sludge were carried out. An upflow anaerobic sludge blanket reactor (UASB) was fed with several ratios of acetate-C/toluene-C loading rates (mg C/L-day: 100/0, 75/25, 50/50, and 0/100). Batch assays with different acetate-C/toluene-C ratios (10/70, 30/50, 50/30, and 65/20 mg C/L) were also done. As the acetate loading rate decreased in the culture, the carbon and nitrate consumption efficiency decreased by 40% and 34%, respectively. HCO(3) (-) and N(2) yields also decreased by 43%. Analysis of the denitrifying community using the denaturing gradient gel electrophoresis technique indicated that there was no clear relationship between its population profile and the metabolic pattern. In batch assays, when the acetate concentration was higher than that of toluene (65 mg acetate-C/L vs 20 mg toluene-C/L), the specific consumption rate of toluene (q(T)) was two times higher than in assays with 20 mg toluene-C/L as the sole electron source (0.006 mg C/mg volatile suspended solids-day). It is proposed that acetate can act by enhancing the growth of microbial populations and as a biochemical enhancer. The results show that acetate addition can be useful to improve the consumption rate of toluene in contaminated water.


Asunto(s)
Acetatos/química , Nitratos/análisis , Aguas del Alcantarillado , Tolueno/análisis , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Aerobiosis , Anaerobiosis , ADN Bacteriano/análisis , Oxidación-Reducción , Aguas del Alcantarillado/química , Aguas del Alcantarillado/microbiología
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