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In recirculating aquaculture systems (RAS), maintaining water quality in aquaculture tanks is a paramount factor for effective fish production. A down-flow hanging sponge (DHS) reactor, a trickling filter system used for water treatment of RAS that employs sponges to retain biomass, has high nitrification activity. However, nitrification in seawater RAS requires a long start-up time owing to the high salinity stress. Therefore, this study aimed to evaluate the nitrification characteristics and changes in the microbial community during the conversion of freshwater to seawater in a DHSreactor fed with ammonia-based artificial seawater. The total ammonia nitrogen concentration reached 1.0â¯mg-N·L-1 (initial concentration 10â¯mg-N·L-1) within 11 days of operation, and nitrate production was observed. The 16â¯S rRNA gene sequence of the DHS-retained sludge indicated that the detection rate of the ammonia-oxidizing archaeon Candidatus Nitrosocosmicus decreased from 23.9â¯% to 14.0â¯% and 25.8-17.6â¯% in the upper and lower parts of the DHS reactor, respectively, after the introduction of seawater. In contrast, the nitrite-oxidizing bacteria Nitrospira spp. increased from 0.1â¯% to 9.5â¯% and from 0.5â¯% to 10.5â¯%, respectively. The ammonia oxidation rates of 0.12 ± 0.064 and 0.051 ± 0.0043â¯mg-N·g-MLVSS-1·h-1 on the 37th day in the upper and bottom layers, respectively. Thus, nitrification in the DHS reactor performed well, even under high-salinity conditions with short operational days. This finding makes the transition from freshwater to saltwater fish in the RAS system simple and economical, and has the potential for early start-up of the RAS.
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The dinoflagellate Prorocentrum triestinum forms high biomass blooms that discolor the water (red tides), which may pose a serious threat to marine fauna and aquaculture exploitations. In this study, the algicidal effect of a bacterial strain (0YLH) belonging to the genus Shewanella was identified and evaluated against P. triestinum. The algicidal effects on the dinoflagellate were observed when P. triestinum was exposed to cell-free supernatant (CFS) from stationary-phase cultures of the 0YLH strain. After 24 h exposure, a remarkable reduction in the photosynthetic efficiency of P. triestinum was achieved (55.9%), suggesting the presence of extracellular bioactive compounds produced by the bacteria with algicidal activity. Furthermore, the CFS exhibited stability and maintained its activity across a wide range of temperatures (20-120 °C) and pH values (3-11). These findings highlight the algicidal potential of the bacterium Shewanella halifaxensis 0YLH as a promising tool for the environmentally friendly biological control of P. triestinum blooms.
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Dinoflagellida , Shewanella , Proliferação Nociva de Algas , AquiculturaRESUMO
BACKGROUND AND PURPOSE: Antiplatelet therapy (APT) is a key element limiting the risk of thromboembolic events (TEE) in neuroendovascular procedures, including aneurysm treatment with flowdiverter. Clopidogrel combined with aspirin is the mostly reported dual APT (DAPT). However, resistance phenomenon and intraindividual efficacy fluctuation are identified limitations. In recent years, ticagrelor has been increasingly used in this indication. We compared these two DAPT regimens for intracranial aneurysm treated with flowdiverter. METHODS: We conducted a multicentric retrospective study from prospectively maintained databases in two high volume centers extracting consecutive patients presenting unruptured intracranial aneurysm treated with flowdiverter and receiving DAPT (May 2015 to December 2019). Two groups were compared according to their DAPT regimen: "ticagrelor+aspirin" and "clopidogrel+aspirin". Clopidogrel group was systematically checked with platelet test inhibition before endovascular procedure. The primary endpoint was composite, defined as any thrombo-embolic event (TEE) or major hemorrhagic event occurring the first 6 months during and after embolization RESULTS: 260 patients met our inclusion criteria. Baseline patients and aneurysms characteristics were comparable between groups, except for aneurysm location, median size and pre-treatment modified Rankin scale. No significant difference was observed regarding the primary composite outcome: 11.5% (12/104) in the ticagrelor group versus 10.9% (17/156) in the clopidogrel group (p = 1.000). There was also no significant difference in secondary outcomes including TEE (10.5 vs 9.0%; p = 0.673), major hemorrhage (0.9 vs 1.2%; p = 0.651) and clinical outcome (at least 1-point mRS worsening during follow up: 6.7% vs 8.3%; p = 0.813). CONCLUSION: First-line DAPT with ticagrelor+aspirin seems as safe and effective as clopidogrel+aspirin regimen.
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Aneurisma Intracraniano , Tromboembolia , Humanos , Clopidogrel/uso terapêutico , Ticagrelor/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/tratamento farmacológico , Estudos Retrospectivos , Aspirina/uso terapêutico , Hemorragia , Resultado do TratamentoRESUMO
BACKGROUND: - scanty articles illustrate the prognostic factors for favorable outcome after endovascular thrombectomy (EVT) in distal vessel occlusion (DMVO). Moreover, the current literature is diversified; conglomerating both primary, secondary, and anterior, posterior circulations embolic strokes in the same shell. PURPOSE: to identify the association between complete reperfusion and favorable outcome following EVT for DMVO in the middle cerebral artery (MCA) territory. METHODS: -we performed a retrospective analysis of prospectively maintained EVT registries at two comprehensive stroke centers between January 2015 and December 2019 for consecutive stroke patients with MCA-DMVO. DMVO was defined as an occlusion of distal M2 and M3 segments of the MCA. Only patients with primary isolated occlusions were included. A multivariate logistic regression was utilized to identify clinical and procedural-related factors associated with the 90-day favorable clinical outcome [defined as modified Rankin score (mRS) 0-2] after EVT. RESULTS: -Out of 1823 within the registries; 66 patients (median age was 72 (60-78) and 59% were males) with primary isolated DMVO of the MCA were eligible for inclusion in the current study. Complete reperfusion was achieved in 56% (37/66) of the patients with no difference among the reperfusion strategies while the favorable outcome was observed in 68% (45/66). In the multivariate analysis, final complete reperfusion [modified Thrombolysis In Cerebral Infarction (mTICI) score 2c-3] was significantly associated with favorable outcome [aOR=7.69; (95% CI 1.73-34.17); p=.01], while higher baseline NIHSS score [aOR=0.82; (95% CI 0.69-0.98); p=.03] and increased imaging to puncture interval [aOR=0.99; (95% CI 0.98, 1.00); p=.01] decreased the probability of the favorable outcome. CONCLUSION: according to our results, complete reperfusion was the most significant predictor of the favorable outcome, while higher baseline NIHSS and longer imaging to puncture interval decreased the probability of the favorable outcome.
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Isquemia Encefálica , Procedimentos Endovasculares , Acidente Vascular Cerebral , Masculino , Humanos , Idoso , Feminino , Infarto da Artéria Cerebral Média/etiologia , Isquemia Encefálica/etiologia , Estudos Retrospectivos , Resultado do Tratamento , Acidente Vascular Cerebral/etiologia , Trombectomia/métodos , Procedimentos Endovasculares/métodosRESUMO
We present a case of a healthy 64-year-old man whose endoscopy showed an irregular subepithelial lesion in the gastric antrum. This lesion was covered by normal mucosa. Biopsies were taken by a bite-on-bite technique. After biopsies, the patient developed arterial bleeding, which was controlled. The anatomopathological study showed a tortuous artery in the submucosa, with a marked hyperplasia of the intima and the internal elastic lamina. These findings were consistent with a gastric arteriovenous malformation versus a Dieulafoy's lesion. This case demonstrates the risk of the bite-on-bite biopsy technique. In our country we have endoscopic ultrasound to assess these lesions, however its availability is low.
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Gastropatias , Doenças Vasculares , Malformações Vasculares , Masculino , Humanos , Pessoa de Meia-Idade , Endoscopia Gastrointestinal , Hemorragia , Biópsia , Hemorragia GastrointestinalRESUMO
The evaluation of kidney function is usually performed through the estimation of the glomerular filtration rate and urine analysis. The evaluation of the kidney morphology through an image complements and enriches this information. However, many of the applications of current imaging techniques are unknown to clinicians. In addition, communication between clinicians and imaging specialists is less common than desirable. In this review, we will describe the imaging methods most frequently used for evaluating kidney function and other clinical situations, in addition to analyzing the most significant advances, particularly in ultrasonography and magnetic resonance imaging, for the early detection and follow-up of kidney damage.
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Taxa de Filtração Glomerular , Nefropatias , Rim , Imageamento por Ressonância Magnética , Humanos , Rim/diagnóstico por imagem , Rim/fisiologia , Taxa de Filtração Glomerular/fisiologia , Nefropatias/diagnóstico por imagem , Nefropatias/fisiopatologia , Testes de Função Renal/métodos , Ultrassonografia/métodosRESUMO
Background White matter hyperintensity (WMH) has been linked to poor clinical outcomes after acute ischemic stroke. Purpose To assess whether the WMH burden on pretreatment MRI scans is associated with an increased risk for symptomatic intracranial hemorrhage (sICH) or poor functional outcome in patients with acute ischemic stroke treated with endovascular thrombectomy (EVT). Materials and Methods In this retrospective study, consecutive patients treated with EVT for anterior circulation acute ischemic stroke at a comprehensive stroke center (where MRI was the first-line pretreatment imaging strategy; January 2015 to December 2017) were included and analyzed. WMH volumes were assessed with semiautomated volumetric analysis at fluid-attenuated inversion recovery MRI by readers who were blinded to clinical data. The associations of WMH burden with sICH and 3-month functional outcome (modified Rankin Scale [mRS] score) were assessed. Results A total of 366 patients were included (mean age, 69 years ± 19 [SD]; 188 women [51%]). Median total WMH volume was 3.61 cm3 (IQR, 1.10-10.83 cm3). Patients demonstrated higher mRS scores with increasing WMH volumes (odds ratio [OR], 1.020 [95% CI: 1.003, 1.037] per 1.0-cm3 increase for each mRS point increase; P = .018) after adjustment for patient and clinical variables. There were no significant associations between WMH severity and 90-day mortality (OR, 1.007 [95% CI: 0.990, 1.024]; P = .40) or the occurrence of sICH (OR, 1.001 [95% CI: 0.978, 1.024]; P = .94). Conclusion Higher white matter hyperintensity burden was associated with increased risk for poor 3-month functional outcome after endovascular thrombectomy for large-vessel occlusive stroke. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Mossa-Basha and Zhu in this issue.
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Arteriopatias Oclusivas , Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Leucoaraiose , Acidente Vascular Cerebral , Substância Branca , Idoso , Feminino , Humanos , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/cirurgia , Leucoaraiose/diagnóstico por imagem , Leucoaraiose/etiologia , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Trombectomia/métodos , Resultado do Tratamento , Substância Branca/diagnóstico por imagemRESUMO
OBJECTIVES: To establish whether collateral circulation was associated with functional outcome in stroke patients with large infarct size (Alberta Stroke Program Early CT Score [ASPECTS] ≤ 5) undergoing endovascular thrombectomy (EVT) METHODS: Consecutive patients with acute ischemic stroke due to large-vessel occlusion in the anterior circulation and an ASPECTS of ≤ 5 were analyzed. Quantification of collateral circulation was performed using a fluid-attenuated inversion recovery vascular hyperintensity (FVH)-ASPECTS rating system (score ranging from 0 [no FVH] to 7 [FVHs abutting all ASPECTS cortical areas]) by two independent neuroradiologists. Good functional outcome was defined by modified Rankin Scale (mRS) score of 0 to 3 at 3 months. We determined the association between FVH score and clinical outcome using multivariable regression analyses. RESULTS: A total of 139 patients (age, 63.1 ± 20.8 years; men, 51.8%) admitted between March 2012 and December 2017 were included. Good functional outcome (mRS 0-3) was observed in 65 (46.8%) patients, functional independence (mRS 0-2) was achieved in 43 (30.9%) patients, and 33 (23.7%) patients died at 90 days. The median FVH score was 4 (IQR, 3-5). FVH score was independently correlated with good outcome (adjusted OR = 1.41 [95% CI, 1.03-1.92]; p = 0.03 per 1-point increase). CONCLUSIONS: In stroke patients with large-volume infarcts, good collaterals as measured by the FVH-ASPECTS rating system are associated with improved outcomes and may help select patients for reperfusion therapy. KEY POINTS: ⢠Endovascular thrombectomy can allow almost 1 in 2 patients with large infarct cores to achieve good functional outcome (modified Rankin Scale [mRS] of 0-3) and 1 in 3 patients to regain functional independence (mRS 0-2) at 3 months. ⢠The extent of FVH score (as reflected by FLAIR vascular hyperintensity [FVH]-Alberta Stroke Program Early CT Score [ASPECTS] values) is associated with functional outcome at 3 months in this patient group.
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Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Adulto , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/cirurgia , Circulação Colateral , Humanos , Infarto , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Trombectomia , Resultado do TratamentoRESUMO
Microalgae are a valuable natural resource for a variety of biocompounds such as carotenoids. The use of different light spectra and irradiance has been considered as a promising option to improve the production of these compounds. The objective of this study was to evaluate the influence of different wavelengths (white, red, and blue) and irradiances (80 and 350 µmol photons/m2/s) on the photosynthetic state, total carotenoids and lutein productivity (HPLC), lipids (Nile red method) and antioxidant activity (DPPH) of the microalgae Muriellopsis sp. (MCH-35). This microalga, which is a potential source of lutein, was isolated from the coastal desert of Antofagasta, Chile, and adapted to grow in seawater. The results indicate that the culture exposed to high-intensity red light showed the highest biomass yield (2.5 g/L) and lutein productivity (>2.0 mg L−1day−1). However, blue light was found to have a stimulating effect on the synthesis of lutein and other carotenoids (>0.8% dry wt). Furthermore, a direct relationship between lipid accumulation and high light intensity was evidenced. Finally, the highest antioxidant activity was observed with high-intensity white light, these values have no direct relationship with lutein productivity. Therefore, the findings of this study could be utilized to obtain biocompounds of interest by altering certain culture conditions during the large-scale cultivation of MCH-35.
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Clorofíceas , Microalgas , Antioxidantes/farmacologia , Biomassa , Carotenoides , Luz , LuteínaRESUMO
BACKGROUND AND PURPOSE: White matter hyperintensity (WMH), a marker of chronic cerebral small vessel disease, might impact the recruitment of leptomeningeal collaterals. We aimed to assess whether the WMH burden is associated with collateral circulation in patients treated by endovascular thrombectomy for anterior circulation acute ischemic stroke. METHODS: Consecutive acute ischemic stroke due to anterior circulation large vessel occlusion and treated with endovascular thrombectomy from January 2015 to December 2017 were included. WMH volumes (periventricular, deep, and total) were assessed by a semiautomated volumetric analysis on fluid-attenuated inversion recovery-magnetic resonance imaging. Collateral status was graded on baseline catheter angiography using the American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology grading system (good when ≥3). We investigated associations of WMH burden with collateral status. RESULTS: A total of 302 patients were included (mean age, 69.1±19.4 years; women, 55.6%). Poor collaterals were observed in 49.3% of patients. Median total WMH volume was 3.76 cm3 (interquartile range, 1.09-11.81 cm3). The regression analyses showed no apparent relationship between WMH burden and the collateral status measured at baseline angiography (adjusted odds ratio, 0.987 [95% CI, 0.971-1.003]; P=0.12). CONCLUSIONS: WMH burden exhibits no overt association with collaterals in large vessel occlusive stroke.
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Circulação Colateral , AVC Isquêmico/patologia , Substância Branca/patologia , Idoso , Idoso de 80 Anos ou mais , Arteriopatias Oclusivas/patologia , Doenças de Pequenos Vasos Cerebrais/patologia , Procedimentos Endovasculares , Feminino , Humanos , AVC Isquêmico/cirurgia , Imageamento por Ressonância Magnética/métodos , Masculino , TrombectomiaRESUMO
OBJECTIVES: To establish whether imaging assessments of irreversibly injured ischemic core and potentially salvageable penumbral volumes and collateral circulation were associated with functional outcome in nonagenarians (90 years or older) undergoing endovascular thrombectomy (EVT). METHODS: Data from a prospectively maintained institutional registry of consecutive stroke patients treated with EVT from January 2012 to December 2018 were retrospectively analyzed. Functional outcome was evaluated with the modified Rankin scale (mRS) at 3 months. mRS score of 0-3 was defined as a good clinical outcome. Ischemic core and penumbral volumes were calculated using the RAPID software. Quantification of collateral circulation was performed using a fluid-attenuated inversion recovery vascular hyperintensity (FVH)-Alberta Stroke Program Early CT Score (ASPECTS) rating system. RESULTS: Among 85 patients (age, 92.4 ± 2.6 years; men, 30.6%) treated with EVT, good outcome (mRS 0-3) was achieved in 29 (34.1%) patients and 31 (36.5%) patients died at 90 days. The median estimated ischemic core volume was 15 mL (IQR, 7-27 mL). The median mismatch volume was 83 mL (IQR, 43-120 mL). The median FVH score was 4 (IQR, 3-4). FVH score was independently associated with good functional outcome (adjusted OR = 1.96 [95% CI, 1.16-3.32]; p = 0.01 per 1-point increase) and mortality (adjusted OR = 0.54 [95% CI, 0.34-0.85]; p = 0.007 per 1-point increase). Ischemic core and mismatch volumes were associated with neither good outcome nor mortality. CONCLUSIONS: In nonagenarians with anterior circulation large-vessel ischemic stroke, good collaterals as measured by the FVH-ASPECTS rating system are independently associated with improved outcomes and may help select patients for reperfusion therapy in this frail population. KEY POINTS: ⢠Endovascular thrombectomy can allow at least 1 in 3 patients older than 90 years of age to achieve good functional outcome (modified Rankin scale of 0-3) at 3 months. ⢠Functional outcome at 3 months is associated with pre-stroke status (number and severity of patients' comorbidities). ⢠A higher FVH score (as reflected by higher FLAIR vascular hyperintensity [FVH]-Alberta Stroke Program Early CT Score [ASPECTS] values) is independently associated with better 3-month functional outcome and mortality in nonagenarians with anterior circulation ischemic stroke.
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Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Idoso de 80 Anos ou mais , Isquemia Encefálica/diagnóstico por imagem , Humanos , Masculino , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Trombectomia , Resultado do TratamentoRESUMO
BACKGROUND AND PURPOSE: The benefit of endovascular thrombectomy (EVT) among nonagenarians (90 years or older) is poorly documented. We aimed to investigate the clinical and imaging factors associated with good outcomes and mortality at 90 days in nonagenarians undergoing EVT for acute ischemic stroke (AIS). METHODS: Data from a prospectively maintained institutional registry of consecutive AIS patients treated with EVT from January 2012 to December 2018 were retrospectively analysed. Comorbid conditions were classified with a modified version of the Charlson Comorbidity Index (CCI). The degree of disability was assessed by the modified Rankin Scale (mRS). Outcomes included good functional outcome (mRS scores of 0-3) and mortality at 90 days. RESULTS: Among 110 patients (age, 92.3 ± 2.5 years; men, 28.2%) treated with EVT, good outcome was achieved in 39 (35.5%) patients, successful reperfusion (modified Thrombolysis in Cerebral Infarction grades of 2b-3) was achieved in 78 (70.9%) patients and 38 (34.5%) patients died at 90 days. The functional outcome at 3 months was associated with pre-stroke status (CCI and pre-stroke mRS score). Successful reperfusion (adjusted odds ratio [OR], 11.6; 95% CI, 1.3-104.2; P = 0.03) and early neurologic improvement at 24 h (adjusted OR, 16.4; 95% CI, 5.2-51.5; P < 0.001) were independent predictors of a good outcome. Early neurological improvement (adjusted OR, 0.06; 95% CI, 0.02-0.23; P < 0.001) was an independent predictor of 90-day mortality. CONCLUSIONS: Successful reperfusion therapy improves the functional outcome of nonagenarians who should not be excluded from EVT. The presence and severity of comorbidities should be considered in the procedural management of this vulnerable population.
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Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Idoso de 80 Anos ou mais , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/terapia , Procedimentos Endovasculares/efeitos adversos , Humanos , Masculino , Reperfusão/efeitos adversos , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Resultado do TratamentoRESUMO
Optimal management of intracranial pressure (ICP) among aneurysmal subarachnoid hemorrhage (aSAH) patients requiring external ventricular drainage (EVD) is controversial. To analyze predictors of delayed cerebral ischemia (DCI)-related cerebral infarction after aSAH and the influence of ICP values on DCI, we prospectively collected consecutive patients with aSAH receiving coiling and requiring EVD. Predictors of DCI-related cerebral infarction (new CT hypodensities developed within the first 3 weeks not related to other causes) were studied. Vasospasm and brain hypoperfusion were studied with CT angiography and CT perfusion (RAPID-software). Among 50 aSAH patients requiring EVD, 21 (42%) developed DCI-related cerebral infarction, while 27 (54%) presented vasospasm. Mean ICP ranged between 2 and 19 mmHg. On the multivariate analysis, the mean ICP (OR = 2, 95%CI = 1.01-3.9, p = 0.042) and the mean hypoperfusion volume on Tmax delay > 6 (OR = 1.2, 95%CI = 1.01-1.3, p = 0.025) were independent predictors of DCI. To predict DCI-related cerebral infarction, Tmax delay > 6 s presented the highest AUC (0.956, SE = 0.025), with a cutoff value of 18 ml showing sensitivity, specificity, PPV, NPV, and accuracy of 90.5% (95%CI = 69-98.8%), 86.2% (95%CI = 68.4-96%), 82.6% (95%CI = 65.4-92%), 92.5% (95%CI = 77-98%), and 88% (95%CI = 75-95%), respectively. The AUC of the mean ICP was 0.825 (SE = 0.057), and the best cutoff value was 6.7 mmHg providing sensitivity, specificity, PPV, NPV, and accuracy of 71.4% (95%CI = 48-89%), 62% (95%CI = 42-79%), 58% (95%CI = 44-70%), 75% (95%CI = 59-86%), and 66% (95%CI = 51-79%) for the prediction of DCI-related cerebral infarction, respectively. Among aSAH patients receiving coiling and EVD, lower ICP (< 6.7 mmHg in our study) could potentially be beneficial in decreasing DCI-related cerebral infarction. Brain hypoperfusion with a volume > 18 ml at Tmax delay > 6 s presents a high sensibility and specificity in prediction of DCI-related cerebral infarction.
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Drenagem/métodos , Procedimentos Endovasculares/métodos , Pressão Intracraniana/fisiologia , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/cirurgia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Hemorragia Subaracnóidea/complicações , Fatores de Tempo , Tomografia Computadorizada por Raios X/métodosRESUMO
Biosorption refers to a physicochemical process where substances are removed from the solution by a biological material (live or dead) via adsorption processes governed by mechanisms such as surface complexation, ion exchange, and precipitation. This study aimed to evaluate the adsorption of Zn2+ in seawater using the microalgal biomass of Tetraselmis marina AC16-MESO "in vivo" and "not alive" at different concentrations of Zn2+ (0, 5, 10, and 20 mg L-1) at 72 h. Analysis was carried out by using the Langmuir isotherms and by evaluating the autofluorescence from microalgae. The maximum adsorption of Zn2+ by the Langmuir model using the Qmax parameter in the living microalgal biomass (Qmax = 0.03051 mg g-1) was more significant than the non-living microalgal biomass of T. marine AC16-MESO (Qmax = 0.02297 mg g-1). Furthermore, a decrease in fluorescence was detected in cells from T. marina AC16-MESO, in the following order: Zn2+ (0 < 20 < 5 < 10) mg L-1. Zn2+ was adsorbed quickly by living cells from T. marine AC16-MESO compared to the non-living microalgal biomass, with a decrease in photosystem II activities from 0 to 20 mg L-1 Zn2+ in living cells.
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Biomassa , Clorófitas/fisiologia , Água do Mar/química , Poluentes Químicos da Água/isolamento & purificação , Zinco/isolamento & purificação , Adsorção , Biodegradação Ambiental , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/metabolismo , Zinco/metabolismoRESUMO
Biofouling control in reverse osmosis membranes (ROMs) is challenging due to the high cost of treatments, and reduction in the life of ROMs. This study characterizes the biofouling in the ROMs from a desalination plant and reports its effective removal using the supernatant obtained from Alteromonas sp. strain Ni1-LEM. The characterization of the bacterial community revealed that the most abundant taxa in ROMs were the genera Fulvivirga and Pseudoalteromonas, and unclassified species of the families Flavobacteriaceae and Sphingomonadaceae. This bacterial community significantly decreased upon treatment with the supernatant from Alteromonas sp. Ni1-LEM, resulting in the prevalence of the genus Pseudoalteromonas. Furthermore, this bacterial supernatant significantly inhibited cell adhesion of seven benthic microalgae isolated from ROMs as well as promoting cell detachment of the existing microbial biofilms. The study showed that the extracellular supernatant modified the conformation of extracellular polymeric substances (EPS) in the biofouling of ROMs without any biocidal effects.
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Alteromonas , Incrustação Biológica , Purificação da Água , Biofilmes , Chile , Humanos , Membranas , Membranas Artificiais , Osmose , PlantasRESUMO
In this study, we determined the effect of drying on extraction kinetics, yield, and lutein content and recovery of the microalga Muriellopsis sp. (MCH35) using the supercritical fluid extraction (SFE) process. The strain was cultivated in an open-raceways reactor in the presence of seawater culture media and arid outdoor conditions in the north of Chile. Spray-drying (SD) and freeze-drying (FD) techniques were used for dehydrating the microalgal biomass. Extraction experiments were performed by using Box-Behnken designs, and the parameters were studied: pressure (30-50 MPa), temperature (40-70 °C), and co-solvent (0-30% ethanol), with a CO2 flow rate of 3.62 g/min for 60 min. Spline linear model was applied in the central point of the experimental design to obtain an overall extraction curve and to reveal extraction kinetics involved in the SFE process. A significant increase in all variables was observed when the level of ethanol (15-30% v/v) was increased. However, temperature and pressure were non-significant parameters in the SFE process. The FD method showed an increase in lutein content and recovery by 0.3-2.5-fold more than the SD method. Overall, Muriellopsis sp. (MCH35) is a potential candidate for cost-effective lutein production, especially in desert areas and for different biotechnological applications.
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Luteína/química , Microalgas , Água/química , Chile , Cromatografia com Fluido SupercríticoRESUMO
INTRODUCTION AND OBJECTIVES: Functional and inflammatory measures have been recommended to corroborate asthma diagnosis in schoolchildren, but the evidence in this regard is conflicting. We aimed to determine, in real-life clinical situation, the value of spirometry, spirometric bronchial reversibility to salbutamol (BDR), bronchial responsiveness to methacholine (MCT) and fractional exhaled nitric oxide (FENO), to corroborate the diagnosis of asthma in children on regular inhaled corticosteroids (ICS) referred from primary care. METHODS: One hundred and seventy-seven schoolchildren with mild-moderate persistent asthma, on treatment with regular ICS, participated in the study. Abnormal tests were defined as FENOâ¯≥â¯27 ppb, BDR (FEV1â¯≥â¯12%) and methacholine PC20â¯≤â¯4â¯mg/mL. RESULTS: The proportions of positive BDR, FENO and MCT, were 16.4%, 33.3%, and 87.0%, respectively. MCT was associated with FENO (pâ¯<â¯0.03) and BDR (pâ¯=â¯0.001); FENO was associated with BDR (pâ¯=â¯0.045), family history of asthma (pâ¯=â¯0.003) and use of asthma medication in the first two years of life (pâ¯=â¯0.004). BDR was significantly related with passive tobacco exposure (pâ¯=â¯0.003). CONCLUSIONS: Spirometry, BDR and BDR had a poor performance for corroborating diagnosis in our asthmatic children on ICS treatment; on the contrary, MCT was positive in most of them, which agrees with previous reports. Although asthma tests are useful to corroborate asthma when positive, clinical diagnosis remains the best current approach for asthma diagnosis, at least while better objective and feasible measurements at the daily practice are available. At present, these tests may have a better role for assessing the management and progression of the condition.
Assuntos
Albuterol/uso terapêutico , Asma/diagnóstico , Hiper-Reatividade Brônquica/diagnóstico , Testes de Provocação Brônquica/métodos , Broncodilatadores/uso terapêutico , Adolescente , Criança , Expiração , Feminino , Humanos , Masculino , Anamnese , Cloreto de Metacolina/administração & dosagem , Óxido Nítrico/metabolismo , EspirometriaRESUMO
Climate change affects population cycles of several species, threatening biodiversity. However, there are few long-term studies on species with conservation issues and restricted distributions. Huemul is a deer endemic to the southern Andes in South America and it is considered endangered mostly due to a 50% reduction of its distribution over the last 500 years. To assess environmental variables potentially affecting huemul population viability and the impact of climate change, we developed population dynamics models. We used a 14-year survey data from Bernardo O'Higgins National Park, coastal Chilean Patagonia. We used Ricker models considering winter and spring temperatures and precipitation as variables influencing huemul population dynamics. We used the Bayesian information criterion (BIC) to select models with the greatest predictive power. The two best models (ΔBIC < 2) included winter temperature and density-dependence population growth drivers. The best model considered a lateral effect, where winter temperature influences carrying capacity and the second best a vertical effect with winter temperature influencing Rmax and carrying capacity. Population viability was evaluated using those models, projecting them over a 100-year period: (a) under current conditions and (b) under conditions estimated by Global Climate Models for 2050 and 2070. The extinction risk and quasi-extinction were estimated for this population considering two critical huemul abundance levels (15 and 30 individuals) for persistence. The population is currently in a quasi-extinction process, with extinction probabilities increasing with climate change. These results are crucial for conservation of species like huemul that have low densities and are threatened by climate change.
Assuntos
Mudança Climática , Cervos , Animais , Teorema de Bayes , Chile , Conservação dos Recursos Naturais , Humanos , Dinâmica Populacional , Medição de RiscoRESUMO
Omega-3 long-chain polyunsaturated fatty acids (n-3 LC PUFAs) and vitamin D3 are essential components of human nutrition. A regular human diet is highly deficient in n-3 LC PUFAs. Fish like salmon are highly recommended in the human diet as they are a major source of high-value n-3 LC PUFAs and vitamin D3. The levels of these nutrients have been decreasing over the last few years in farmed salmon, whose production urgently needs sustainable sources of these nutrients. The microalga Nannochloropsis gaditana (NG) is known for its naturally high potential for the production of eicosapentaenoic (EPA, 20:5 n-3) fatty acid. A commercial diet for Atlantic salmon was supplemented with 1% and 10% of spray-dried NG grown under controlled conditions for a high EPA content. Salmon were harvested on day 49, following which, boneless and skinless salmon meat was recovered from fish and analyzed for the fatty acid profile, total fat, and vitamin D3. Vitamin D3, EPA, and docosapentaenoic fatty acid (DPA, 22:5 n-3) levels were significantly increased (p < 0.05) by supplementing the basal diet with 10% NG, thus, NG represents a novel, functional, natural ingredient and a sustainable source of n-3 LC-PUFAs that can raise the levels of healthy fats and vitamin D3 in farmed salmon meat.
Assuntos
Colecalciferol/análise , Ácido Eicosapentaenoico/análise , Ácidos Graxos Insaturados/análise , Microalgas/química , Salmo salar/metabolismo , Animais , HumanosRESUMO
BACKGROUND: Despite series of endovascular recanalization of chronically occluded ICA (COICA) have been already reported, technical aspects of this strategy were not described. We discussed technical details and feasibility of this strategy. CLINICAL PRESENTATION: Five COICA (C1-cavernous ICA) patients presenting symptomatic hypoperfusion were recanalized with multiple coronary and carotid stents. All patients experienced long-term reperfusion with resolution of the clinical symptoms. CONCLUSION: Endovascular revascularization of COICA appears feasible and associated with improvement of the hypoperfusion.