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1.
Klin Onkol ; 36(1): 71-74, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36868835

RESUMO

BACKGROUND: Supportive care alone cannot be indicated for cancers for which established standard therapy exists unless there is a specific reason. Due to the refusal of standard therapy by the patient after proper explanation of the therapy, we experienced a long-term follow-up of >10 years with supportive care alone in an epidermal growth factor receptor (EGFR) mutated lung cancer patient. CASE: A 70-year-old woman was referred due to the right lung with some ground glass opacities (GGOs). One of the GGOs which was resected in another hospital had been confirmed to be EGFR mutation-positive lung adenocarcinoma. Although EGFR-tyrosine kinase inhibitor (TKI) was explained to be the standard therapy, the patient refused receiving the therapy and wished to follow up imaging of the remaining GGOs. During the follow-up period of 13 years, the each GGO showed a gradual increase. The doubling time of the largest GGO and that of serum carcinoembryonic antigen was > 2,000 days, respectively. CONCLUSION: Although very rare, some of EGFR mutated lung adenocarcinoma might have a very slow progression. Clinical course of this patient provides useful information to the clinical practice of future patients who may have similar clinical courses.


Assuntos
Adenocarcinoma de Pulmão , Adenocarcinoma , Neoplasias Pulmonares , Feminino , Humanos , Idoso , Receptores ErbB , Mutação
4.
Transplant Proc ; 55(1): 129-133, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36581508

RESUMO

BACKGROUND: Nonadherence among pediatric transplant recipients is a significant problem that reduces graft survival and leads to poor kidney graft outcomes. It is, however, extremely difficult to detect during a regular follow-up. This study, therefore, aimed to investigate the risk factors involved in nonadherence, focusing on unexplained transient hyperuricemia in pediatric kidney transplant (KTx) recipients at a single pediatric center. METHODS: This retrospective study included 167 patients who underwent KTx at our pediatric center. A Cox proportional hazards analysis was performed to evaluate the risk of nonadherence using the following factors: age, sex, body mass index SD score, transient hyperuricemia, hypertension, and follow-up period. RESULTS: Nonadherence was identified in 19 patients (11%), with the average (SD) age and post-KTx duration at diagnosis being 17.21 (4.73) years and 79.21 (38.77) months, respectively. Thirty-four patients (20%) were diagnosed with transient hyperuricemia at a median of 14 months after KTx. On multivariate Cox regression analysis, transient hyperuricemia was the only independent risk factor for nonadherence after KTx. CONCLUSIONS: Transient hyperuricemia was identified as one of the risk factors for nonadherence after KTx; therefore, careful monitoring for transient hyperuricemia may allow early detection of nonadherence.


Assuntos
Hiperuricemia , Transplante de Rim , Humanos , Criança , Transplante de Rim/efeitos adversos , Hiperuricemia/etiologia , Estudos Retrospectivos , Rim , Fatores de Risco , Sobrevivência de Enxerto
6.
Klin Onkol ; 35(2): 150-154, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35459340

RESUMO

BACKGROUND: Immune checkpoint inhibitors (ICPIs) can cause immune-related adverse events (irAEs) in organs throughout the body. Of the irAEs, ICPI-induced interstitial lung disease (ILD) is the most notable one that can be life-threatening. No less than that, ICPI-induced cardiac irAEs are serious ones and are recently attracting attention. IrAEs usually develop within a few months after the initiation of ICPI treatment, but some of them occur after a long period of time from the start of treatment. CASE: A 60-year-old male patient with squamous cell carcinoma developed ICPI-induced ILD more than 2 years after the initiation of ICPI therapy. A few months after the ICPI-induced ILD improved, he developed heart failure, which was presumed to be caused by impaired cardiac ejection. Both irAEs improved without administration of corticosteroids. CONCLUSION: Although rare, these irAEs may appear even after a long period of time from the start of administration, and chest physicians should be careful of late-onset irAEs.


Assuntos
Carcinoma de Células Escamosas , Doenças Pulmonares Intersticiais , Carcinoma de Células Escamosas/induzido quimicamente , Carcinoma de Células Escamosas/tratamento farmacológico , Cardiotoxicidade , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Doenças Pulmonares Intersticiais/induzido quimicamente , Doenças Pulmonares Intersticiais/patologia , Masculino , Pessoa de Meia-Idade
9.
J Physiol Pharmacol ; 67(4): 563-573, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27779477

RESUMO

Recent progress in endoscopic techniques has revealed that non-steroidal anti-inflammatory drugs (NSAIDs) often cause ulcers in the small intestine in humans, but effective therapy is not available at present. In the present study, we investigated the effects of feeding condition and the amount of dietary fiber (DF) in the diet on the formation of gastrointestinal ulcers induced by NSAIDs in dogs. Several types of diets containing various percentages of DF were given to dogs. Indomethacin (1 or 3 mg/kg, p.o.), ketoprofen (2 mg/kg, s.c.), or fulnixin (1 mg/kg, s.c.) was administered once daily at 10 a.m. after a morning meal or without a morning meal (fasted condition) for 3 - 7 days. Gastrointestinal lesions were examined 24 h after the final dose of the drugs. When indomethacin (3 mg/kg) was administered after a morning meal (fed condition) for 7 days, it produced many lesions in the small intestine. However, when it was given in the fasted condition without the morning meal, the lesions were markedly decreased. All the NSAIDs given after feeding of regular dry food containing 6% DF once a day for 3 days produced many lesions in the small intestine. The lesions were decreased or increased in dogs given prescription diets containing low DF (1.1%) and high DF (15.4%), respectively. Furthermore, lesions were not observed in dogs given canned diet containing very low DF (< 0.1%), whereas lesions appeared again in dogs given canned diet supplemented with cellulose (3 or 10%) but not with pectin (10%). These results suggested that both feeding condition and insoluble DF, such as cellulose in the diet, play an important role in the formation of NSAID-induced small intestinal lesions, and that a diet with no or low amounts of DF may decrease gastrointestinal side-effects associated with the use of NSAIDs.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Fibras na Dieta/farmacologia , Enteropatias/induzido quimicamente , Intestino Delgado/efeitos dos fármacos , Úlcera/induzido quimicamente , Animais , Celulose/farmacologia , Suplementos Nutricionais , Cães , Feminino , Indometacina/efeitos adversos , Enteropatias/patologia , Intestino Delgado/patologia , Cetoprofeno/efeitos adversos , Masculino , Pectinas/farmacologia , Estômago/efeitos dos fármacos , Estômago/patologia , Gastropatias/induzido quimicamente , Gastropatias/patologia , Úlcera/patologia
10.
J Physiol Pharmacol ; 66(5): 719-29, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26579578

RESUMO

Previously, we reported that TGP-580, a mutein of human basic fibroblast growth factor (bFGF), accelerated the healing of gastric and duodenal ulcers in rats. In the present study, we examined the effect of TGP-580 on the healing of colonic ulcers. In male Sprague Dawley rats, ulcers were induced in the colon 6 cm from the anus by enema of 50 µl of 3% N-ethylmaleimide, a sulfhydryl alkylator. The lesions were examined under a dissecting microscope (x10). The concentration of bFGF in the ulcerated colon was measured by enzyme immunoassay, and both the distribution of bFGF and the density of microvessels in the ulcer bed were examined by immunohistochemical staining. The content of bFGF in the ulcerated colon was markedly increased associated with ulcer healing, and ulcer healing was significantly delayed by intravenous administration of a monoclonal antibody for bFGF (MAb 3H3) once daily for 10 days. In the ulcer bed, many cells such as fibroblasts, vascular endothelial cells and macrophages were positively stained with bFGF antiserum. TGP-580, human bFGF or dexamethasone was given intracolonally twice daily for 10 days, starting the day after ulcer induction. TGP-580 (0.2 - 20 µg/ml, 200 µl/rat) dose-dependently accelerated ulcer healing, and its effect was more than 10 times stronger than that of human bFGF. Density (µm/0.01 mm(2)) of microvessels in the ulcer bed was significantly increased by treatment with TGP-580, and there was a good correlation between the density of microvessels and the decrease of ulcerated area (R(2) = 0.633). On the other hand dexamethasone (20 µg/ml) inhibited angiogenesis in the ulcer bed and delayed ulcer healing. These results suggest that angiogenesis in the ulcer bed plays an important role in ulcer healing, and that bFGF mutein TGP-580 accelerated colonic ulcer healing, at least in part, by stimulating angiogenesis, whereas glucocorticoids may delay the healing by inhibiting angiogenesis.


Assuntos
Indutores da Angiogênese/farmacologia , Doenças do Colo/tratamento farmacológico , Fatores de Crescimento de Fibroblastos/farmacologia , Úlcera/tratamento farmacológico , Indutores da Angiogênese/administração & dosagem , Animais , Colo/efeitos dos fármacos , Colo/patologia , Doenças do Colo/patologia , Dexametasona/farmacologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Fatores de Crescimento de Fibroblastos/administração & dosagem , Glucocorticoides/farmacologia , Humanos , Masculino , Neovascularização Fisiológica/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia , Úlcera/patologia
11.
Plant Biol (Stuttg) ; 17(3): 632-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25287526

RESUMO

Non-photosynthetic and hydrophilic chlorophyll (Chl) proteins, called water-soluble Chl-binding proteins (WSCPs), are distributed in various species of Chenopodiaceae, Amaranthaceae, Polygonaceae and Brassicaceae. Based on their photoconvertibility, WSCPs are categorised into two classes: Class I (photoconvertible) and Class II (non-photoconvertible). Chenopodium album WSCP (CaWSCP; Class I) is able to convert the chlorin skeleton of Chl a into a bacteriochlorin-like skeleton under light in the presence of molecular oxygen. Potassium iodide (KI) is a strong inhibitor of the photoconversion. Because KI attacks tyrosine residues in proteins, tyrosine residues in CaWSCP are considered to be important amino acid residues for the photoconversion. Recently, we identified the gene encoding CaWSCP and found that the mature region of CaWSCP contained four tyrosine residues: Tyr13, Tyr14, Tyr87 and Tyr134. To gain insight into the effect of the tyrosine residues on the photoconversion, we constructed 15 mutant proteins (Y13A, Y14A, Y87A, Y134A, Y13-14A, Y13-87A, Y13-134A, Y14-87A, Y14-134A, Y87-134A, Y13-14-87A, Y13-14-134A, Y13-87-134A, Y14-87-134A and Y13-14-87-134A) using site-directed mutagenesis. Amazingly, all the mutant proteins retained not only chlorophyll-binding activity, but also photoconvertibility. Furthermore, we found that KI strongly inhibited the photoconversion of Y13-14-87-134A. These findings indicated that the four tyrosine residues are not essential for the photoconversion.


Assuntos
Chenopodium album/metabolismo , Proteínas de Ligação à Clorofila/metabolismo , Clorofila/metabolismo , Fotossíntese , Tirosina/metabolismo , Sequência de Aminoácidos , Clorofila A , Luz , Mutação , Solubilidade
12.
Drug Res (Stuttg) ; 65(12): 629-34, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25549254

RESUMO

OBJECTIVE: The lymphocyte immunosuppressant sensitivity test has been used to predict the pharmacodynamics of immunosuppressive drugs for the purpose of preventing acute rejection and infection after renal transplantation. On the other hand, measuring the ATP levels in peripheral CD4+ lymphocytes is also able to monitor the risks of rejection and infection in transplant recipients. In the present study, we examined the relationship between the mycophenolic acid pharmacodynamics and the ATP levels in peripheral lymphocytes before and after renal transplantation. METHODS: We examined both the pharmacological efficacy of mycophenolic acid and the lymphocyte ATP levels before and 2, 4 and 6 weeks after the operation in 20 renal transplant recipients. The drug's pharmacological efficacy was evaluated by the 50% inhibitory concentration of the drug against the in vitro proliferation of peripheral blood lymphocytes activated by T cell mitogen. The ATP levels in peripheral CD4+ lymphocytes were measured by the Immuknow assay kit. The relationships between the mycophenolic acid pharmacodynamics and ATP levels in peripheral lymphocytes were examined in these recipients. RESULTS: The immunosuppressive effects of mycophenolic acid against mitogen-activated lymphocyte proliferation were significantly and positively correlated with the lymphocyte ATP levels, but only at 6 weeks after transplantation. The relationship was not significant before or at 2 or 4 weeks after the operation. CONCLUSION: Our present data raised the possibility that evaluating the pharmacological efficacy of mycophenolic acid pre-transplantation and monitoring the ATP level 6 weeks after transplantation can predict the risk of rejection and/or infection in renal transplant recipients.


Assuntos
Trifosfato de Adenosina/metabolismo , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Transplante de Rim/métodos , Ativação Linfocitária/efeitos dos fármacos , Ácido Micofenólico/farmacologia , Adulto , Feminino , Humanos , Masculino , Mitógenos/antagonistas & inibidores , Adulto Jovem
13.
Chem Commun (Camb) ; 50(94): 14786-9, 2014 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-25318407

RESUMO

We describe a method for creating robust and stable core-shell polymer microspheres decorated with inorganic (IO) nanoparticles (NPs) by a self-organization process and heterocoagulation using a mussel-inspired polymer adhesive layer between the IO NPs and the microspheres.


Assuntos
Materiais Biomiméticos/química , Bivalves , Ouro/química , Nanopartículas Metálicas/química , Microesferas , Nanocompostos/química , Polímeros/química , Adesividade , Animais
14.
J Comp Pathol ; 151(2-3): 264-70, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25086870

RESUMO

Fourteen renal biomarkers were compared with measurement of glomerular filtration rate (GFR) in detecting acute kidney injury (AKI) in beagle dogs given gentamicin (40 mg/kg/day by subcutaneous injection) for 7 consecutive days. Serum and urinary biomarkers were measured before administration of gentamicin and then on days 4 and 8 after starting administration. GFR was derived by use of a simplified equation. Increased urinary cystatin C and decreased GFR occurred from day 4 and were detected before increases in blood urea nitrogen (BUN) and serum creatinine concentrations and changes in other urinary parameters. The closest correlation was between urinary cystatin C and GFR. At termination, microscopical examination revealed extensive necrosis of proximal tubular epithelium with hyaline casts in the kidney of treated dogs. These data indicate that urinary cystatin C is the most sensitive index of kidney injury and GFR reflects the kidney functional mass.


Assuntos
Injúria Renal Aguda/diagnóstico , Biomarcadores/análise , Cistatina C/urina , Taxa de Filtração Glomerular , Injúria Renal Aguda/metabolismo , Animais , Cistatina C/sangue , Cães , Gentamicinas/toxicidade
15.
Water Sci Technol ; 69(12): 2519-25, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24960016

RESUMO

For decades, arid and semi-arid regions in Africa have faced issues related to water availability for drinking, irrigation and livestock purposes. To tackle these issues, a laboratory scale greywater treatment system based on high rate algal pond (HRAP) technology was investigated in order to guide the operation of the pilot plant implemented in the 2iE campus in Ouagadougou (Burkina Faso). Because of the high suspended solids concentration generally found in effluents of this system, the aim of this study is to improve the performance of HRAPs in term of algal productivity and removal. To determine the selection mechanism of self-flocculated algae, three sets of sequencing batch reactors (SBRs) and three sets of continuous flow reactors (CFRs) were operated. Despite operation with the same solids retention time and the similarity of the algal growth rate found in these reactors, the algal productivity was higher in the SBRs owing to the short hydraulic retention time of 10 days in these reactors. By using a volume of CFR with twice the volume of our experimental CFRs, the algal concentration can be controlled during operation under similar physical conditions in both reactors.


Assuntos
Eucariotos , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Purificação da Água/métodos , Biomassa , Reatores Biológicos , Burkina Faso , Floculação , Projetos Piloto , Lagoas , Instalações de Eliminação de Resíduos
16.
Water Res ; 47(19): 7078-86, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24200002

RESUMO

Emission of nitrous oxide (N2O) during biological wastewater treatment is of growing concern since N2O is a major stratospheric ozone-depleting substance and an important greenhouse gas. The emission of N2O from a lab-scale granular sequencing batch reactor (SBR) for partial nitrification (PN) treating synthetic wastewater without organic carbon was therefore determined in this study, because PN process is known to produce more N2O than conventional nitrification processes. The average N2O emission rate from the SBR was 0.32 ± 0.17 mg-N L(-1) h(-1), corresponding to the average emission of N2O of 0.8 ± 0.4% of the incoming nitrogen load (1.5 ± 0.8% of the converted NH4(+)). Analysis of dynamic concentration profiles during one cycle of the SBR operation demonstrated that N2O concentration in off-gas was the highest just after starting aeration whereas N2O concentration in effluent was gradually increased in the initial 40 min of the aeration period and was decreased thereafter. Isotopomer analysis was conducted to identify the main N2O production pathway in the reactor during one cycle. The hydroxylamine (NH2OH) oxidation pathway accounted for 65% of the total N2O production in the initial phase during one cycle, whereas contribution of the NO2(-) reduction pathway to N2O production was comparable with that of the NH2OH oxidation pathway in the latter phase. In addition, spatial distributions of bacteria and their activities in single microbial granules taken from the reactor were determined with microsensors and by in situ hybridization. Partial nitrification occurred mainly in the oxic surface layer of the granules and ammonia-oxidizing bacteria were abundant in this layer. N2O production was also found mainly in the oxic surface layer. Based on these results, although N2O was produced mainly via NH2OH oxidation pathway in the autotrophic partial nitrification reactor, N2O production mechanisms were complex and could involve multiple N2O production pathways.


Assuntos
Reatores Biológicos/microbiologia , Consórcios Microbianos/genética , Óxido Nitroso/análise , Óxido Nitroso/metabolismo , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Amônia/metabolismo , Processos Autotróficos , Concentração de Íons de Hidrogênio , Hidroxilamina/metabolismo , Hibridização in Situ Fluorescente , Nitrificação , Eliminação de Resíduos Líquidos/instrumentação
17.
J Anim Sci ; 91(11): 5240-6, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24045472

RESUMO

This study was performed to clarify whether a formula (Holstein equation) based on a single blood sample and the isotonic, nonionic, iodine contrast medium iodixanol in Holstein dairy cows can apply to the estimation of glomerular filtration rate (GFR) for beef cattle. To verify the application of iodixanol in beef cattle, instead of the standard tracer inulin, both agents were coadministered as a bolus intravenous injection to identical animals at doses of 10 mg of I/kg of BW and 30 mg/kg. Blood was collected 30, 60, 90, and 120 min after the injection, and the GFR was determined by the conventional multisample strategies. The GFR values from iodixanol were well consistent with those from inulin, and no effects of BW, age, or parity on GFR estimates were noted. However, the GFR in cattle weighing less than 300 kg, aged<1 yr old, largely fluctuated, presumably due to the rapid ruminal growth and dynamic changes in renal function at young adult ages. Using clinically healthy cattle and those with renal failure, the GFR values estimated from the Holstein equation were in good agreement with those by the multisample method using iodixanol (r=0.89, P=0.01). The results indicate that the simplified Holstein equation using iodixanol can be used for estimating the GFR of beef cattle in the same dose regimen as Holstein dairy cows, and provides a practical and ethical alternative.


Assuntos
Bovinos/fisiologia , Meios de Contraste/farmacocinética , Taxa de Filtração Glomerular/veterinária , Inulina/farmacocinética , Ácidos Tri-Iodobenzoicos/farmacocinética , Envelhecimento , Animais , Bovinos/sangue , Feminino , Taxa de Filtração Glomerular/fisiologia , Inulina/sangue , Masculino , Ácidos Tri-Iodobenzoicos/sangue
18.
Water Environ Res ; 85(5): 387-90, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23789567

RESUMO

The effectiveness of degasification using a degassing membrane to improve chemical oxygen demand (COD) removal efficiency was investigated using a bench-scale upflow anaerobic sludge blanket (UASB) reactor. Vacuum degasification was able to transfer dissolved gas in the bulk liquid of the UASB reactor inside the membrane. Such a process might provide thermodynamically favorable conditions for the degradation of organic compounds. The COD-removal efficiency improved from 83% during normal operation to 90% during the degassing operation.


Assuntos
Reatores Biológicos , Membranas Artificiais , Anaerobiose , Peróxido de Hidrogênio , Concentração de Íons de Hidrogênio , Oxigênio/química , Oxigênio/metabolismo , Fenóis/química , Eliminação de Resíduos Líquidos/métodos , Água/química , Poluentes Químicos da Água , Purificação da Água
19.
Nutr Diabetes ; 3: e70, 2013 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-23712282

RESUMO

OBJECTIVE: Yacon is a perennial plant forming a clump of >20 big, edible underground tubers. Yacon, which originates from South America, has become increasingly popular in the Japanese diet for tubers have a lower caloric value and a high fiber content. Recent studies have suggested that yacon feeding ameliorates diabetes as indicated by reduced blood glucose. METHODS: We fed male Zucker fa/fa rats for 5 weeks with isocaloric normal chow diet containing from 6.5% control aroid or 6.5% yacon. Insulin sensitivity was evaluated by euglycemic-hyperinsulinemic clamp study. RESULTS: Body weight was comparable between yacon- and aroid-fed rats. In the basal state, yacon feeding had an effect to lower fasting glucose levels from 184.1±4.1 to 167.8±2.7 mg dl(-1) (P<0.01), as well as basal hepatic glucose output (HGO) from 9.9±0.4 to 7.4 ± 0.2 mg kg(-1) per min (P<0.01). During the clamp studies, the glucose infusion rate required to maintain euglycemia was increased by 12.3% in yacon-fed rat. The insulin suppression of HGO was also increased in yacon-fed rats compared with control rats (85.3±2.4% vs 77.0±3.0%; P<0.05), whereas the glucose disposal rate was not different between the two groups. Consistent with the clamp data, the insulin-stimulated phosphorylation of Akt was significantly enhanced in liver but not in skeletal muscle. Furthermore, tribbles 3 (Trb3) expression, which is a negative regulator of Akt activity, was markedly reduced in the liver of yacon-fed rats compared with control rats. CONCLUSION: These results indicate that the effect of yacon feeding to reduce blood glucose is likely due to its beneficial effects on hepatic insulin sensitivity in the insulin resistant state.

20.
Appl Environ Microbiol ; 79(13): 4087-93, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23624480

RESUMO

We examined nitrate-dependent Fe(2+) oxidation mediated by anaerobic ammonium oxidation (anammox) bacteria. Enrichment cultures of "Candidatus Brocadia sinica" anaerobically oxidized Fe(2+) and reduced NO3(-) to nitrogen gas at rates of 3.7 ± 0.2 and 1.3 ± 0.1 (mean ± standard deviation [SD]) nmol mg protein(-1) min(-1), respectively (37°C and pH 7.3). This nitrate reduction rate is an order of magnitude lower than the anammox activity of "Ca. Brocadia sinica" (10 to 75 nmol NH4(+) mg protein(-1) min(-1)). A (15)N tracer experiment demonstrated that coupling of nitrate-dependent Fe(2+) oxidation and the anammox reaction was responsible for producing nitrogen gas from NO3(-) by "Ca. Brocadia sinica." The activities of nitrate-dependent Fe(2+) oxidation were dependent on temperature and pH, and the highest activities were seen at temperatures of 30 to 45°C and pHs ranging from 5.9 to 9.8. The mean half-saturation constant for NO3(-) ± SD of "Ca. Brocadia sinica" was determined to be 51 ± 21 µM. Nitrate-dependent Fe(2+) oxidation was further demonstrated by another anammox bacterium, "Candidatus Scalindua sp.," whose rates of Fe(2+) oxidation and NO3(-) reduction were 4.7 ± 0.59 and 1.45 ± 0.05 nmol mg protein(-1) min(-1), respectively (20°C and pH 7.3). Co-occurrence of nitrate-dependent Fe(2+) oxidation and the anammox reaction decreased the molar ratios of consumed NO2(-) to consumed NH4(+) (ΔNO2(-)/ΔNH4(+)) and produced NO3(-) to consumed NH4(+) (ΔNO3(-)/ΔNH4(+)). These reactions are preferable to the application of anammox processes for wastewater treatment.


Assuntos
Bactérias Anaeróbias/metabolismo , Reatores Biológicos , Compostos Ferrosos/metabolismo , Nitratos/metabolismo , Compostos de Amônio Quaternário/metabolismo , Bactérias Anaeróbias/genética , Concentração de Íons de Hidrogênio , Hibridização in Situ Fluorescente , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência , Oxirredução , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Especificidade da Espécie , Temperatura
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