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The first committed step in the leucine biosynthetic pathway is catalyzed by α-isopropylmalate synthase (α-IPMS, EC 2.3.3.13), which in the Saccaromycotina subphylum of Ascomycete yeasts is frequently encoded by duplicated genes. Following a gene duplication event, the two copies may be preserved presumably because the encoded proteins diverge in either functional properties and/or cellular localization. The genome of the petite-negative budding yeast Lachancea kluyveri includes two SAKL0E10472 (LkLEU4) and SAKL0F05170 g (LkLEU4BIS) paralogous genes, which are homologous to other yeast α-IPMS sequences. Here, we investigate whether these paralogous genes encode functional α-IPMS isozymes and whether their functions have diverged. Molecular phylogeny suggested that the LkLeu4 isozyme is located in the mitochondria and LkLeu4BIS in the cytosol. Comparison of growth rates, leucine intracellular pools and mRNA levels, indicate that the LkLeu4 isozyme is the predominant α-IPMS enzyme during growth on glucose as carbon source. Determination of the kinetic parameters indicates that the isozymes have similar affinities for the substrates and for the feedback inhibitor leucine. Thus, the diversification of the physiological roles of the genes LkLEU4 and LkLEU4BIS involves preferential transcription of the LkLEU4 gene during growth on glucose and different subcellular localization, although ligand interactions have not diverged.
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2-Isopropilmalato Sintase , Saccharomycetales , 2-Isopropilmalato Sintase/química , 2-Isopropilmalato Sintase/genética , 2-Isopropilmalato Sintase/metabolismo , Glucose/metabolismo , Isoenzimas/genética , Isoenzimas/metabolismo , Leucina/metabolismo , Saccharomyces cerevisiae/metabolismo , Saccharomycetales/metabolismoRESUMO
PURPOSE: Extra Corporeal Membrane Oxygenation (ECMO) is used in cases of severe respiratory and/or circulatory failure over periods of several days to several weeks. Its circuitry requires a closely monitored anticoagulation therapy that is empirically supported by activated clotting time (ACT)-a method often associated with large inter- and intraindividual variability. We aimed to compare the measurement of heparin activity with ACT and the direct measurement of the heparin activity (anti-Xa) in a large ECMO population. METHODS: All patients treated by venoarterial or venovenous ECMO in our intensive care unit between January 2014 and December 2015 were prospectively included. A concomitant measurement of the anti-Xa activity and ACT was performed on the same sample collected twice a day (morning-evening) for unfractionated heparin adaptation with an ACT target range of 180 to 220 seconds. RESULTS: One hundred and nine patients (men 69.7%, median age 54 years) treated with ECMO (70.6% venoarterial) were included. Spearman analysis found no correlation between anti-Xa and ACT (ρ < 0.4) from day 1 and worsened over time. Kappa analysis showed no agreement between the respective target ranges of ACT and anti-Xa. CONCLUSIONS: We demonstrate that concomitant measurement of ACT and anti-Xa activity is irrelevant in ECMO patients. Since ACT is poorly correlated with heparin dosage, anti-Xa activity appears to be a more suitable assay for anticoagulation monitoring.
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Anticoagulantes/administração & dosagem , Testes de Coagulação Sanguínea/estatística & dados numéricos , Monitoramento de Medicamentos/estatística & dados numéricos , Oxigenação por Membrana Extracorpórea , Inibidores do Fator Xa/sangue , Coagulação Sanguínea/efeitos dos fármacos , Testes de Coagulação Sanguínea/métodos , Monitoramento de Medicamentos/métodos , Feminino , Heparina/administração & dosagem , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Estatísticas não ParamétricasRESUMO
BACKGROUND: The objective of this study was to review Vancouver B2 and B3 periprosthetic hip fractures treated with uncemented modular fluted tapered stems to analyze survivorship, risk factors for stem subsidence, and clinical outcomes. METHODS: We identified 61 Vancouver B2 and B3 periprosthetic hip fractures treated with modular fluted tapered implants. Survivorship, radiographic outcomes, and clinical outcomes were assessed. The mean age at the time of surgery was 72 years, mean body mass index was 30, and mean follow-up was 4.5 years (range, 2-10 years). RESULTS: Survivorship free of reoperation or implant revision at 5 years was 89% and 93%, respectively. Eight (13%) stems subsided a mean distance of 18 ± 8 mm (range, 8-28 mm). Stem subsidence was not correlated with age, gender, Vancouver fracture classification, stem bypass, stem length, or stem diameter. Subsidence was correlated with Dorr C type femora (50% vs 7%, 95% confidence interval 9%-72%; P = .007) and strut grafting (50% vs 9%, 95% confidence interval 6%-70%; P = .01). All cases of subsidence stabilized without revision. Subsidence was not correlated with nonunion, reoperation, revision, or a clinical outcome. CONCLUSIONS: Modular fluted tapered stems had excellent survivorship free of reoperation and implant revision when used for the treatment of Vancouver B2 and B3 periprosthetic femur fractures. Poor bone morphology and the use of strut grafts, both proxies for compromised bone stock and distal fracture patterns, were correlated with stem subsidence. All subsided stems stabilized, and noted subsidence did not portend a worse clinical outcome. LEVEL OF EVIDENCE: Level III, retrospective cohort.
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Artroplastia de Quadril/efeitos adversos , Prótese de Quadril/efeitos adversos , Fraturas Periprotéticas/cirurgia , Reoperação/efeitos adversos , Reoperação/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fêmur/cirurgia , Fraturas do Quadril/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Resultado do TratamentoRESUMO
We propose a definition of entropy for stochastic processes. We provide a reproducing kernel Hilbert space model to estimate entropy from a random sample of realizations of a stochastic process, namely functional data, and introduce two approaches to estimate minimum entropy sets. These sets are relevant to detect anomalous or outlier functional data. A numerical experiment illustrates the performance of the proposed method; in addition, we conduct an analysis of mortality rate curves as an interesting application in a real-data context to explore functional anomaly detection.
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The combination of different sources of information is a problem that arises in several situations, for instance, when data are analysed using different similarity measures. Often, each source of information is given as a similarity, distance, or a kernel matrix. In this paper, we propose a new class of methods which consists of producing, for anomaly detection purposes, a single Mercer kernel (that acts as a similarity measure) from a set of local entropy kernels and, at the same time, avoids the task of model selection. This kernel is used to build an embedding of data in a variety that will allow the use of a (modified) one-class Support Vector Machine to detect outliers. We study several information combination schemes and their limiting behaviour when the data sample size increases within an Information Geometry context. In particular, we study the variety of the given positive definite kernel matrices to obtain the desired kernel combination as belonging to that variety. The proposed methodology has been evaluated on several real and artificial problems.
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Many viral diseases exhibit seasonal behavior and can be affected by environmental stressors. Using time-series correlation charts extrapolated from worldwide data, we provide strong support for the seasonal development of COVID-19 regardless of the immunity of the population, behavioral changes, and the periodic appearance of new variants with higher rates of infectivity and transmissibility. Statistically significant latitudinal gradients were also observed with indicators of global change. Using the Environmental Protection Index (EPI) and State of Global Air (SoGA) metrics, a bilateral analysis of environmental health and ecosystem vitality effects showed associations with COVID-19 transmission. Air quality, pollution emissions, and other indicators showed strong correlations with COVID-19 incidence and mortality. Remarkably, EPI category and performance indicators also correlated with latitude, suggesting cultural and psychological diversity in human populations not only impact wealth and happiness but also planetary health at latitudinal level. Looking forward, we conclude there will be a need to disentangle the seasonal and global change effects of COVID-19 noting that countries that go against the health of the planet affect health in general.
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During the current crisis caused by the COVID-19 pandemic, Wearable IoT (WIoT) health devices have become essential resources for remote monitoring of the main physiological signs affected by this disease. As well as sensors, microprocessor, and wireless communication elements are widely studied, the power supply unit has the same importance for the WIoT technology, since the autonomy of the system between recharges is of great importance. This letter presents the design of the power supply system of a WIoT device capable of monitoring oxygen saturation and body temperature, sending the collected data to an IoT platform. The supply system is based on a three-stage block consisting of a rechargeable battery, battery charge controller, and dc voltage converter. The power supply system is designed and implemented as a prototype in order to test performance and efficiency. The results show that the designed block provides a stable supply voltage avoiding energy losses, which makes it an efficient and rapidly developing system.
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In Saccharomyces cerevisiae, the transcriptional repressor Nrg1 (Negative Regulator of Glucose-repressed genes) and the ß-Zip transcription factor Rtg3 (ReTroGrade regulation) mediate glucose repression and signalling from the mitochondria to the nucleus, respectively. Here, we show a novel function of these two proteins, in which alanine promotes the formation of a chimeric Nrg1/Rtg3 regulator that represses the ALT2 gene (encoding an alanine transaminase paralog of unknown function). An NRG1/NRG2 paralogous pair, resulting from a post-wide genome small-scale duplication event, is present in the Saccharomyces genus. Neo-functionalization of only one paralog resulted in the ability of Nrg1 to interact with Rtg3. Both nrg1Δ and rtg3Δ single mutant strains were unable to use ethanol and showed a typical petite (small) phenotype on glucose. Neither of the wild-type genes complemented the petite phenotype, suggesting irreversible mitochondrial DNA damage in these mutants. Neither nrg1Δ nor rtg3Δ mutant strains expressed genes encoded by any of the five polycistronic units transcribed from mitochondrial DNA in S. cerevisiae. This, and the direct measurement of the mitochondrial DNA gene complement, confirmed that irreversible damage of the mitochondrial DNA occurred in both mutant strains, which is consistent with the essential role of the chimeric Nrg1/Rtg3 regulator in mitochondrial DNA maintenance.
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Transcriptional control of the fixK gene in Rhizobium etli and R. leguminosarum bv. viciae is governed by a two-component signal transduction system that diverts from the conventional FixL-FixJ cascade that occurs in model rhizobia. Although a fixL gene, encoding a hybrid histidine kinase (hFixL), is present in R. etli, no fixJ, the cognate response regulator, has been identified. In this work, we present evidence that the pRet42f-located open reading frame RHE_PF00530 (fxkR) encodes a novel response regulator indispensable for fixKf activation under microaerobic growth. Moreover, results from complementation assays demonstrate that the activation of fixKf expression requires the presence of both hFixL and FxkR, and that the fxkR ortholog from R. leguminosarum bv. viciae is able to substitute for FxkR transcriptional control in R. etli. In addition, in these two organisms, hFixL- and FxkR-related proteins were identified in other bacteria, located in close proximity to a fixK-related gene. Using reporter fusions, site-directed mutagenesis, and electrophoretic mobility shift assays, we identified the FxkR binding site upstream from the transcriptional start site of fixKf. Similar to our previous observations for fixL and fixKf mutants, a null mutation in fxkR does not affect the symbiotic effectiveness of the strain. Thus, our findings reveal that FxkR is the long-standing missing key regulator that allows the transduction of the microaerobic signal for the activation of the FixKf regulon.
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Proteínas de Bactérias/metabolismo , Rhizobium etli/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Sítios de Ligação , Ensaio de Desvio de Mobilidade Eletroforética , Regulação Bacteriana da Expressão Gênica/genética , Regulação Bacteriana da Expressão Gênica/fisiologia , Mutagênese Sítio-Dirigida , Rhizobium etli/genética , Transdução de Sinais/genética , Transdução de Sinais/fisiologiaRESUMO
Seasonal behaviour is an attribute of many viral diseases. Like other 'winter' RNA viruses, infections caused by the causative agent of COVID-19, SARS-CoV-2, appear to exhibit significant seasonal changes. Here we discuss the seasonal behaviour of COVID-19, emerging viral phenotypes, viral evolution, and how the mutational landscape of the virus affects the seasonal attributes of the disease. We propose that the multiple seasonal drivers behind infectious disease spread (and the spread of COVID-19 specifically) are in 'trade-off' relationships and can be better described within a framework of a 'triangle of viral persistence' modulated by the environment, physiology, and behaviour. This 'trade-off' exists as one trait cannot increase without a decrease in another. We also propose that molecular components of the virus can act as sensors of environment and physiology, and could represent molecular culprits of seasonality. We searched for flexible protein structures capable of being modulated by the environment and identified a galectin-like fold within the N-terminal domain of the spike protein of SARS-CoV-2 as a potential candidate. Tracking the prevalence of mutations in this structure resulted in the identification of a hemisphere-dependent seasonal pattern driven by mutational bursts. We propose that the galectin-like structure is a frequent target of mutations because it helps the virus evade or modulate the physiological responses of the host to further its spread and survival. The flexible regions of the N-terminal domain should now become a focus for mitigation through vaccines and therapeutics and for prediction and informed public health decision making.
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Background: The United States Armed Forces completed their withdrawal from Afghanistan on August 30th, 2021, ending 20 years of war in Afghanistan. This rapid timeline from announcement to withdrawal and subsequent power transfer had profound consequences on the Afghan people, particularly in the domains of health and healthcare. Methods: On 15 September 2021, we posted an anonymous online cross-sectional survey on social media (Twitter, Facebook, and WhatsApp groups) to collect data about respondents from Afghanistan. Questions focused on COVID-19 symptoms, concerns, and individual care with a focus on changes related to the United States (US) withdrawal from Afghanistan. The form was composed of 17 questions which included multiple choice, single choice, and numeric options. All questions were optional including demographic data. Results: Our survey yielded 1,074 responses from the Farsi version and 572 responses from the Pashto version for a total of 1,646 responses. 1,286 (80%) of respondents were in Afghanistan at the time of survey submission. Concerning the US withdrawal from Afghanistan, 26% (412) respondents were extremely concerned and 12% (181) were moderately concerned. A majority of respondents report concerns regarding mental health due to the US withdrawal. 27% (418) report extreme concern, 12% (186) report moderate concern, and 15% (229) report a little concern. There is a significant difference in the proportions of concern (for US withdrawal generally, as well as physical and mental health) across gender. 49% of Female respondents report extreme concern regarding the US withdrawal compared to 22% of Male respondents (P < 0.001). With respect to physical health concerns 36% of Females report extreme concern compared to 16% of Males (P < 0.001). Finally on the mental health concerns, 54% of Females report extreme concern compared to 22% of Males (P < 0.001). Conclusion: The results from this survey are susceptible to the possibility of internal validity and/or external validity. However, we are accepting of those possibilities considering this survey wasn't designed to be bulletproof, but rather serve as a voice for those who can't be heard and to inform the public of the hardships occurring across the globe due to a steadfast retraction of the US footprint from their soil. Our findings indicate salient changes and public health concerns among Afghans following the US withdrawal from the region. These concerns varied across gender and ethnic groups. Our findings may serve as the first step in addressing the health concerns of Afghans following two decades of US military presence. The results should be understood through the limitations associated with a survey study design. Future research and policy aimed at tackling short and long-term health and social concerns in Afghanistan should consider the role of US withdrawal.
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COVID-19 , Mídias Sociais , COVID-19/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Saúde Mental , Inquéritos e Questionários , Estados Unidos/epidemiologiaRESUMO
Rhizobium etli CFN42 is unable to use nitrate for respiration and lacks nitrate reductase activity as well as the nap or nar genes encoding respiratory nitrate reductase. However, genes encoding proteins closely related to denitrification enzymes, the norCBQD gene cluster and a novel nirKnirVnnrRnnrU operon are located on pCFN42f. In this study, we carried out a genetic and functional characterization of the reductases encoded by the R. etli nirK and norCB genes. By gene fusion expression analysis in free-living conditions, we determined that R. etli regulates its response to nitric oxide through NnrR via the microaerobic expression mediated by FixKf. Interestingly, expression of the norC and nirK genes displays a different level of dependence for NnrR. A null mutation in nnrR causes a drastic drop in the expression of norC, while nirK still exhibits significant expression. A thorough analysis of the nirK regulatory region revealed that this gene is under both positive and negative regulation. Functional analysis carried out in this work demonstrated that reduction of nitrite and nitric oxide in R. etli requires the reductase activities encoded by the norCBQD and nirK genes. Levels of nitrosylleghemoglobin complexes in bean plants exposed to nitrate are increased in a norC mutant but decreased in a nirK mutant. The nitrate-induced decline in nitrogenase-specific activity observed in both the wild type and the norC mutant was not detected in the nirK mutant. This data indicate that bacterial nitrite reductase is an important contributor to the formation of NO in bean nodules in response to nitrate.
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Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica/fisiologia , Phaseolus/microbiologia , Rhizobium etli/metabolismo , Simbiose/fisiologia , Proteínas de Bactérias/genética , Óxido Nítrico/metabolismo , Oxigênio , Rhizobium etli/genética , Transdução de SinaisRESUMO
BACKGROUND: PURPOSE: To evaluate Pentacam and OPD-Scan parameters in the early detection of keratoconus. DESIGN: Retrospective case-control study. METHODS: Case group included 50 clinically unaffected fellow eyes diagnosed with asymmetric keratoconus showing subtle qualitative changes at the 0.5-D sensitivity OPD-Scan scale, as well as normal anterior and back elevation difference map at Belin/Ambrósio enhanced ectasia display (BAD) at the Pentacam. Control group included 172 normal eyes that underwent Lasik surgery and presented no complications throughout the 2-year follow-up period. OPD-Scan and Pentacam parameters were compared, calculating sensitivity, specificity, and area under the receiver operating characteristic curve (AUC). A multivariate analysis was performed using Pentacam or OPD-Scan variables, and a model using variables of both devices. RESULTS: Pentacam variables with AUC ≥0.8 were keratoconus index (0.85), index of height decentration (0.81), and overall deviation at BAD (0.8). OPD-Scan variables with AUC ≥0.8 were keratoconus prediction index (0.83), surface asymmetry index (0.83), and total of higher-order trefoil aberration (0.8). In the multivariate analysis, the AUC was 0.85 in the case of OPD-Scan whereas it was 0.89 in the case of Pentacam. When combining all variables from the 2 devices, the AUC was 0.93, with a sensitivity of 82% and a specificity of 94%. CONCLUSIONS: Several parameters of OPD-Scan and Pentacam can be useful to differentiate cases from normal control eyes, demonstrating even better results when combining parameters of both devices. Anterior corneal indexes were the most important parameters to discriminate both groups.
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Córnea/patologia , Paquimetria Corneana/métodos , Topografia da Córnea/métodos , Ceratocone/diagnóstico , Adulto , Área Sob a Curva , Estudos de Casos e Controles , Dilatação Patológica/diagnóstico , Diagnóstico Precoce , Feminino , Humanos , Masculino , Curva ROC , Estudos RetrospectivosRESUMO
We report the results of transcranial ultrasound monitoring in three patients with intracranial arterial stenosis of the middle cerebral artery treated with the only drug-eluting balloon certificated for intracranial use in highly symptomatic intracranial arterial stenosis, ELUTAX "3" (AR Baltic Medical). We performed transcranial Doppler ultrasounds 24 h, 72 h, 10 days, 15 days and 30 days after the angioplasty, thereby measuring mean flow velocity (MFV) in the maximum stenosis area in patients with symptomatic steno-occlusive disease of the middle cerebral artery treated with ELUTAX "3". Two patients were treated during mechanical thrombectomy (MT) due to acute ischemic stroke and one patient was treated on elective basis due to symptomatic pre-occlusive stenosis, with recurrent transient ischemic attacks (TIAs) refractory to medical therapy. In Case 1, the first transcranial Doppler ultrasounds evidenced MFV of 348 cm/s, with progressive MFV reduction until 15 days post-treatment, with MFV of 177 cm/s. In Case 2, 24 h after angioplasty had an MFV of 258 cm/s, decreasing to 103 cm/s at 30 days. Case 3 had an MFV of 436 cm/s before angioplasty that immediately decreased after the procedure to 364 cm/s, with a final MFV of 260 cm/s at 30 days. We have recorded a progressive MFV reduction in intracranial arterial stenosis, with better outcomes in patients treated during MT. In our experience, the use of ELUTAX "3" for the treatment of symptomatic intracranial arterial stenosis achieves a progressive improvement of stenosis, evident in the first weeks, to a higher extent in cases of occlusive thrombosis. More studies are needed to provide more information about this device.
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Angioplastia com Balão , Isquemia Encefálica , Stents Farmacológicos , Preparações Farmacêuticas , Acidente Vascular Cerebral , Velocidade do Fluxo Sanguíneo , Constrição Patológica/diagnóstico por imagem , Humanos , Ultrassonografia Doppler TranscranianaRESUMO
Humic substances are redox-active organic molecules, which play pivotal roles in several biogeochemical cycles due to their electron-transferring capacity involving multiple abiotic and microbial transformations. Based on the redox properties of humic substances, and the metabolic capabilities of microorganisms to reduce and oxidize them, we hypothesized that they could mediate the anaerobic oxidation of methane (AOM) coupled to the reduction of nitrous oxide (N2O) in wetland sediments. This study provides several lines of evidence indicating the coupling between AOM and the reduction of N2O through an extracellular electron transfer mechanism mediated by the redox active functional groups in humic substances (e.g., quinones). We found that the microbiota of a sediment collected from the Sisal wetland (Yucatán Peninsula, southeastern Mexico) was able to reduce N2O (4.6 ± 0.5 µmol N2O g sed. -1 day-1) when reduced humic substances were provided as electron donor in a close stoichiometric relationship. Furthermore, a microbial enrichment derived from the wetland sediment achieved simultaneous 13CH4 oxidation (1.3 ± 0.1 µmol 13CO2 g sed. -1 day-1) and N2O reduction (25.2 ± 0.5 µmol N2O g sed. -1 day-1), which was significantly dependent on the presence of humic substances as an extracellular electron shuttle. Taxonomic characterization based on 16S rRNA gene sequencing revealed Acinetobacter (a É£-proteobacterium), the Rice Cluster I from the Methanocellaceae and an uncultured archaeon from the Methanomicrobiaceae family as the microbes potentially involved in AOM linked to N2O reduction mediated by humic substances. The findings reported here suggest that humic substances might play an important role to prevent the emission of greenhouse gases (CH4 and N2O) from wetland sediments. Further efforts to evaluate the feasibility of this novel mechanism under the natural conditions prevailing in ecosystems must be considered in future studies.
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Novel biotechnologies to valorize waste emissions are based on the use of specialized microbial groups that produce different compounds of industrial interest. On this scenario, the retention of such specific microorganisms in the system is of critical interest; however, the potential limitations of working with simplified cultures in a competitive open environment are neither fully explored nor well understood. In this work, a series of biofilters treating methanol vapors coupled with heterologous endochitinase production were used to evaluate the performance of a specialized microbial population during a typical open-to-environment operation. The biofilters were inoculated with a transformed strain of Pichia pastoris and were operated identically for about 90 days. The results showed that the biofiltration performance became diverse with time in terms of the elimination capacity (EC) shifting from a variation coefficient of 1.5% (EC = 274 ± 24, 279 ± 5, and 281.9 ± 25 g/[m3 h]) at the beginning of the operation to 33% (EC = 297 ± 9, 338 ± 7, and 341 ± 2 g/[m3 h]) at the end of operation. Epifluorescence analysis and cloning-sequencing suggested that P. pastoris remained as the dominant microorganism of methanol degradation, whereas diverse airborne bacteria, including Ochrobactrum spp. and Klebsiella oxytoca, played a secondary role possibly associated with the consumption of intermediates. Overall, this study found that low diversity systems operated under non-sterile conditions could be susceptible to contamination with external microorganisms causing a diversifying behavior at the performance and microbial community levels. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2715, 2019.
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Biotecnologia/métodos , Metanol/metabolismo , Pichia/metabolismo , Reatores Biológicos/microbiologia , Quitinases/metabolismo , Microbiota/fisiologiaRESUMO
Symbiotic nitrogen-fixing bacteria express a terminal oxidase with a high oxygen affinity, the cbb3-type oxidase encoded by the fixNOQP operon. Previously, we have shown that, in Rhizobium etli CFN42, the repeatedfixNOQP operons (fixNOQPd and fixNOQPf) have a differential role in nitrogen fixation. Only the fixNOQPd operon is required for the establishment of an effective symbiosis; microaerobic induction of this operon is under the control of at least three transcriptional regulators, FixKf, FnrNd, and FnrNchr, belonging to the Crp/Fnr family. In this work, we describe two novel Crp/Fnr-type transcriptional regulators (StoRd and StoRf, symbiotic terminal oxidase regulators) that play differential roles in the control of key genes for nitrogen fixation. Mutations either in stoRd or stoRf enhance the microaerobic expression of both fixNOQP reiterations, increasing also the synthesis of the cbb3-type oxidase in nodules. Despite their structural similarity, a differential role of these genes was also revealed, since a mutation in stoRd but not in stoRf enhanced both the expression of fixKf and the nitrogen-fixing capacity of R. etli CFN42.
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Proteínas de Bactérias/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/genética , Regulação da Expressão Gênica de Plantas , Fixação de Nitrogênio/genética , Rhizobium etli/genética , Fatores de Transcrição/metabolismo , Proteínas de Bactérias/genética , Complexo IV da Cadeia de Transporte de Elétrons/biossíntese , Mutação , Óperon , Rhizobium etli/enzimologia , Rhizobium etli/metabolismo , Simbiose/genética , Simbiose/fisiologia , Fatores de Transcrição/genéticaRESUMO
Introducción. La diabetes mellitus (DM) es una de las enfermedades crónicas más comunes, siendo una de las causas principales de mortalidad de la población mun-dial. La dermatoglifia es empleada como instrumento para el hallazgo de ciertos aspectos biológicos en diferentes poblaciones. Objetivo. Reconocer, a partir de una revisión sistemática, la relevancia que tiene la dermatoglifia como medio de hallazgo de diabetes mellitus. Metodología. Revisión de literatura científica en bases de datos como Sciencedi-rect, PubMed, Scopus y BVS, en las cuales se extrajo información después de co-rrer la ecuación de búsqueda con términos MESH. Posteriormente, fueron revisados para incluir aquellos artículos relacionados con DM y dermatoglifia. Para todo el proceso se siguió la metodología PRISMA, evaluando los artículos con la escala de sesgo de Cochrane y el nivel de evidencia y recomendación con escala SIGN. Resultados. Después de una revisión de 475 artículos, se incluyeron ocho artículos, y al ser evaluados fueron clasificados cinco artículos 2+ y tres 2-, con nivel de reco-mendación D. Conclusión. La dermatoglifía es una herramienta útil como medio de detección de la DM. Sin embargo, es necesario realizar estudios de cohortes para demostrarlo en di-ferentes poblaciones, como la colombiana. En ese sentido, se encuentra que el 70% de los artículos revisados demuestran que la predicción de hallazgo de DM es efectiva. Sin embargo, el 30% de las investigaciones dentro de esta revisión no consideran que sea una herramienta lo suficientemente óptima para descubrir la patología en la población.
Introduction. Diabetes mellitus (DM) is one of the most common chronic diseases, be-ing one of the main causes of mortality in the world population. Dermatoglyphics is used as an instrument for the discovery of certain biological aspects in different populations.Objective. To recognize, by doing a systematic review, the relevance of dermato-glyphics as a means of finding diabetes mellitus. Methodology. Review of scientific literature in databases such as Sciencedirect, PubMed, Scopus, and VHL, in which information was extracted after running the search equation with MESH terms. After that, they were revised to include those articles related to DM and dermatoglyphics. For the entire process, the PRISMA methodology was followed, evaluating the articles with the Cochrane bias scale and the level of evidence and recommendation with the SIGN scale. Results. After a review of 475 articles, eight articles were included, and when evalu-ated, five articles were classified as 2+ and three as 2-, with a level D recommendation. Conclusion. Dermatoglyphics is a useful tool as a means of detecting DM. However, it is necessary to carry out cohort studies to demonstrate this in different populations, such as the Colombian population. 70% of the reviewed articles show that the prediction of DM finding is effective. Nevertheless, 30% of the investigations within this review do not consider it to be a sufficiently optimal tool to discover the pathology in the population
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Dermatoglifia , Diabetes Mellitus , Doença Crônica , Causalidade , Estudos de Coortes , Predisposição Genética para Doença , Medical Subject Headings , Diagnóstico , Metodologia como Assunto , Revisão SistemáticaRESUMO
BACKGROUND: The appendix inflammatory process is the most common cause of chronic abdominal pain in the right lower quadrant. The frequency of appendiceal lumen obstruction by fecalith ranges from 10 to 20%; few cases of obstruction by multiple fecaliths had been reported. CLINICAL CASE: Sixty-nine years old male, diabetic and hypertensive in control, he underwent bowel resection 30 years previously. He completed 6 months with intermittent, mild pain in the right lower quadrant abdomen; 14 days prior to admission with increasing pain, nausea, vomiting, constipation, abdominal distension and absence of peristalsis; 12,750 leukocytes, neutrophils 90%; plain abdominal radiography without specific bowel pattern, TAC with 3 dense images in right lower quadrant; exploratory laparotomy was performed and perforated appendix with 3 free fecaliths was found. Histopathological report showed fibrosis and lymphocytic infiltrate in the muscle layer of the cecal appendix consistent with chronic appendicitis. CONCLUSIONS: The most common obstruction of the appendix lumen is by a single fecalith. In this case the patient had chronic appendicitis secondary to appendiceal lumen obstruction by multiple fecaliths. Reviewing the international literature any case of chronic appendicitis associated with the presence of multiple fecaliths was found.