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1.
Curr Microbiol ; 81(7): 173, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750329

RESUMO

The ability of fungi to effectively sense and internalize signals related to extracellular changing environments is essential for survival. This adaptability is particularly important for fungal pathogens of humans and plants that must sense and respond to drastic environmental changes when colonizing their hosts. One of the most important physicochemical factors affecting fungal growth and development is the pH. Ascomycota fungal species possess mechanisms such as the Pal/Rim pathway for external pH sensing and adaptation. However, the conservation of this mechanism in other fungi, such as Ustilaginomycetes is still little studied. To overcome this knowledge gap, we used a comparative genomic approach to explore the conservation of the Pal/Rim pathway in the 13 best sequenced and annotated Ustilaginomycetes. Our findings reveal that the Rim proteins and the Endosomal Sorting Complex Required for Transport (ESCRT) proteins are conserved in Ustilaginomycetes. They conserve the canonical domains present in Pal/Rim and ESCRT proteins of Ascomycota. This study sheds light on the molecular mechanisms used by these fungi for responding to extracellular stresses such as the pH, and open the door to further experimentations for understanding the molecular bases of the signaling in Ustilaginomycetes.


Assuntos
Proteínas Fúngicas , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Concentração de Íons de Hidrogênio , Transdução de Sinais , Ascomicetos/genética , Ascomicetos/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Filogenia
2.
Pediatr Dermatol ; 41(3): 458-460, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38305078

RESUMO

Mast cells (MCs) can release a variety of biologically active mediators under different circumstances, such as fever or vaccination. Our aim was to evaluate the incidence and severity of MC activation symptoms induced by SARS-CoV-2 virus (COVID-19) infection and vaccination in a cohort of 92 pediatric patients with cutaneous mastocytosis. Our findings support previous evidence on the safety of COVID-19 infection and vaccination in patients with MC disorders.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Mastocitose Cutânea , SARS-CoV-2 , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Estudos Transversais , Estudos Retrospectivos , Vacinação
3.
Biochem Genet ; 62(1): 352-370, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37347449

RESUMO

Malignant pleural mesothelioma (MPM) is a rare and aggressive neoplasm of the pleural tissue that lines the lungs and is mainly associated with long latency from asbestos exposure. This tumor has no effective therapeutic opportunities nowadays and has a very low five-year survival rate. In this sense, identifying molecular events that trigger the development and progression of this tumor is highly important to establish new and potentially effective treatments. We conducted a meta-analysis of genome-wide expression studies publicly available at the Gene Expression Omnibus (GEO) and ArrayExpress databases. The differentially expressed genes (DEGs) were identified, and we performed functional enrichment analysis and protein-protein interaction networks (PPINs) to gain insight into the biological mechanisms underlying these genes. Additionally, we constructed survival prediction models for selected DEGs and predicted the minimum drug inhibition concentration of anticancer drugs for MPM. In total, 115 MPM tumor transcriptomes and 26 pleural tissue controls were analyzed. We identified 1046 upregulated DEGs in the MPM samples. Cellular signaling categories in tumor samples were associated with the TNF, PI3K-Akt, and AMPK pathways. The inflammatory response, regulation of cell migration, and regulation of angiogenesis were overrepresented biological processes. Expression of SOX17 and TACC1 were associated with reduced survival rates. This meta-analysis identified a list of DEGs in MPM tumors, cancer-related signaling pathways, and biological processes that were overrepresented in MPM samples. Some therapeutic targets to treat MPM are suggested, and the prognostic potential of key genes is shown.


Assuntos
Neoplasias Pulmonares , Mesotelioma Maligno , Mesotelioma , Neoplasias Pleurais , Humanos , Mesotelioma/genética , Mesotelioma/metabolismo , Fosfatidilinositol 3-Quinases , Neoplasias Pleurais/genética , Neoplasias Pleurais/metabolismo , Neoplasias Pulmonares/patologia
4.
BMC Med Ethics ; 25(1): 31, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38504267

RESUMO

BACKGROUND: The prioritization protocols for accessing adult critical care in the extreme pandemic context contain tiebreaker criteria to facilitate decision-making in the allocation of resources between patients with a similar survival prognosis. Besides being controversial, little is known about the public acceptability of these tiebreakers. In order to better understand the public opinion, Quebec and Ontario's protocols were presented to the public in a democratic deliberation during the summer of 2022. OBJECTIVES: (1) To explore the perspectives of Quebec and Ontario citizens regarding tiebreakers, identifying the most acceptable ones and their underlying values. (2) To analyze these results considering other public consultations held during the pandemic on these criteria. METHODS: This was an exploratory qualitative study. The design involved an online democratic deliberation that took place over two days, simultaneously in Quebec and Ontario. Public participants were selected from a community sample which excluded healthcare workers. Participants were first presented the essential components of prioritization protocols and their related issues (training session day 1). They subsequently deliberated on the acceptability of these criteria (deliberation session day 2). The deliberation was then subject to thematic analysis. RESULTS: A total of 47 participants from the provinces of Quebec (n = 20) and Ontario (n = 27) took part in the online deliberation. A diverse audience participated excluding members of the healthcare workforce. Four themes were identified: (1) Priority to young patients - the life cycle - a preferred tiebreaker; (2) Randomization - a tiebreaker of last resort; (3) Multiplier effect of most exposed healthcare workers - a median acceptability tiebreaker, and (4) Social value - a less acceptable tiebreaker. CONCLUSION: Life cycle was the preferred tiebreaker as this criterion respects intergenerational equity, which was considered relevant when allocating scarce resources to adult patients in a context of extreme pandemic. Priority to young patients is in line with other consultations conducted around the world. Additional studies are needed to further investigate the public acceptability of tiebreaker criteria.


Assuntos
COVID-19 , Adulto , Humanos , COVID-19/epidemiologia , Ontário/epidemiologia , Quebeque , Pandemias , Cuidados Críticos
5.
J Surg Res ; 284: 1-5, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36525816

RESUMO

INTRODUCTION: Despite efforts to advance clinical research through collaboration between Latin and North American partners, there remains persistent barriers to performing investigative work. To overcome these obstacles, a team of over 100 surgeon-leaders from 18 Latin American countries founded the Asociación de Cirujanos Traumatólogos de las Américas (ACTUAR). One of ACTUAR's first major collaborative projects, initiated in 2018, was a prospective, observational, multicenter study evaluating quality of life after open tibia fracture management. The current study identified common barriers experienced during the initiation of this study, as exemplified through two sites in Mexico. The study aims to identify obstacles to proactively overcome these in future collaborative work. METHODS: Two research assistants from University of California, San Francisco and two research coordinators from Mexico were recruited to share their experiences, identify common barriers experienced during site enrollment and on-boarding for the ACTUAR open tibia study, and discuss possible solutions. RESULTS: Barriers were organized into three categories: structural, logistical, and intrapersonal. Structural barriers included differences in patient populations and resources between private and public hospitals. Logistical barriers included ambiguous ethical review processes, internet availability, and low patient follow-up. Primary enrollment as a resident responsibility led to some intrapersonal barriers. Potential solutions were identified for each barrier and agreed upon by all collaborators. CONCLUSIONS: Multiple barriers were identified by research personnel who initiated a prospective surgical clinical research study in Mexico. Through collaborative approaches, many potential solutions may help overcome these barriers and build locally led research capacity in Latin America.


Assuntos
Qualidade de Vida , Centros de Traumatologia , Humanos , México , Estudos Prospectivos , América Latina
6.
Chaos ; 33(6)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37368040

RESUMO

The identification of brain dynamical changes under different cognitive conditions with noninvasive techniques such as electroencephalography (EEG) is relevant for the understanding of their underlying neural mechanisms. The comprehension of these mechanisms has applications in the early diagnosis of neurological disorders and asynchronous brain computer interfaces. In both cases, there are no reported features that could describe intersubject and intra subject dynamics behavior accurately enough to be applied on a daily basis. The present work proposes the use of three nonlinear features (recurrence rate, determinism, and recurrence times) extracted from recurrence quantification analysis (RQA) to describe central and parietal EEG power series complexity in continuous alternating episodes of mental calculation and rest state. Our results demonstrate a consistent mean directional change of determinism, recurrence rate, and recurrence times between conditions. Increasing values of determinism and recurrence rate were present from the rest state to mental calculation, whereas recurrence times showed the opposite pattern. The analyzed features in the present study showed statistically significant changes between rest and mental calculation states in both individual and population analysis. In general, our study described mental calculation EEG power series as less complex systems in comparison to the rest state. Moreover, ANOVA showed stability of RQA features along time.


Assuntos
Eletroencefalografia , Dinâmica não Linear , Eletroencefalografia/métodos , Encéfalo , Descanso
7.
Anal Chem ; 94(21): 7536-7544, 2022 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-35576165

RESUMO

Bio-oils are precursors for biofuels but are highly corrosive necessitating further upgrading. Furthermore, bio-oil samples are highly complex and represent a broad range of chemistries. They are complex mixtures not simply because of the large number of poly-oxygenated compounds but because each composition can comprise many isomers with multiple functional groups. The use of hyphenated ultrahigh-resolution mass spectrometry affords the ability to separate isomeric species of complex mixtures. Here, we present for the first time, the use of this powerful analytical technique combined with chemical reactivity to gain greater insights into the reactivity of the individual isomeric species of bio-oils. A pyrolysis bio-oils and its esterified bio-oil were analyzed using gas chromatography coupled to Fourier transform ion cyclotron resonance mass spectrometry, and in-house software (KairosMS) was used for fast comparison of the hyphenated data sets. The data revealed a total of 10,368 isomers in the pyrolysis bio-oil and an increase to 18,827 isomers after esterification conditions. Furthermore, the comparison of the isomeric distribution before and after esterification provide new light on the reactivities within these complex mixtures; these reactivities would be expected to correspond with carboxylic acid, aldehyde, and ketone functional groups. Using this approach, it was possible to reveal the increased chemical complexity of bio-oils after upgrading and target detection of valuable compounds within the bio-oils. The combination of chemical reactions alongside with in-depth molecular characterization opens a new window for the understanding of the chemistry and reactivity of complex mixtures.


Assuntos
Óleos de Plantas , Polifenóis , Biocombustíveis/análise , Biomassa , Misturas Complexas , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta , Óleos de Plantas/química , Polifenóis/química
8.
J Natl Compr Canc Netw ; 20(1): 45-53, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34991066

RESUMO

BACKGROUND: To describe short-term outcomes and independent predictors of 28-dayx mortality in adult patients with hematologic malignancies and septic shock defined by the new Third International Consensus Definitions (Sepsis-3) criteria. METHODS: We performed a retrospective cohort study of patients admitted to the medical ICU with septic shock from April 2016 to March 2019. Demographic and clinical features and short-term outcomes were collected. We used descriptive statistics to summarize patient characteristics, logistic regression to identify predictors of 28-day mortality, and Kaplan-Meier plots to assess survival. RESULTS: Among the 459 hematologic patients with septic shock admitted to the ICU, 109 (23.7%) had received hematopoietic stem cell transplant. The median age was 63 years (range, 18-89 years), and 179 (39%) were women. Nonsurvivors had a higher Charlson comorbidity index (P=.007), longer length of stay before ICU admission (P=.01), and greater illness severity at diagnosis and throughout the hospital course (P<.001). The mortality rate at 28 days was 67.8% and increased with increasing sequential organ failure assessment score on admission (odds ratio [OR], 1.11; 95% CI, 1.03-1.20), respiratory failure (OR, 3.12; 95% CI, 1.49-6.51), and maximum lactate level (OR, 1.16; 95% CI, 1.10-1.22). Aminoglycosides administration (OR, 0.42; 95% CI, 0.26-0.69), serum albumin (OR, 0.51; 95% CI, 0.31-0.86), and granulocyte colony-stimulating factor (G-CSF) (OR, 0.40; 95% CI, 0.24-0.65) were associated with lower 28-day mortality. Life support limitations were present in 81.6% of patients at death. At 90 days, 19.4% of the patients were alive. CONCLUSIONS: Despite efforts to enhance survival, septic shock in patients with hematologic malignancies is still associated with high mortality rates and poor 90-day survival. These results demonstrate the need for an urgent call to action with higher awareness, including the further evaluation of interventions such as earlier ICU admission, aminoglycosides administration, and G-CSF treatment.


Assuntos
Neoplasias Hematológicas , Sepse , Choque Séptico , Adulto , Feminino , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/terapia , Mortalidade Hospitalar , Humanos , Unidades de Terapia Intensiva , Pessoa de Meia-Idade , Estudos Retrospectivos , Choque Séptico/terapia
9.
Int Microbiol ; 25(1): 17-26, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34185162

RESUMO

The life cycle of Ustilago maydis involves alternation of a haploid saprophytic yeast-like stage and a dikaryotic hyphal virulent form. Under in vitro conditions, basidiocarps are formed. Analysis of the transcriptional network of basidiocarp formation revealed the possible involvement of a Tec transcription factor (Tec1, UMAG_02835) in the process. In some Ascomycota, Tec factors are involved in mycelial formation, pathogenesis, and interaction with other regulatory elements, but their role in Basidiomycota species is almost unknown. Accordingly, we proceeded to determine the role of this gene in U. maydis by its mutation. Tec1 was found to be a crucial factor for normal mating, basidiocarp development, and virulence, all of the functions related to the dikaryotic stage dependent of the b genes, whereas dimorphism and resistance to different stress conditions occurring in the haploid stage were not affected in tec1 mutants. The observation that mutants showed a low residual wild-type phenotype suggests the presence of a secondary mechanism that partially compensates the loss of Tec1.


Assuntos
Basidiomycota , Ustilago , Carpóforos , Proteínas Fúngicas/genética , Fatores de Transcrição/genética , Ustilago/genética , Virulência
10.
Sensors (Basel) ; 22(10)2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35632193

RESUMO

Stress has become a common condition and is one of the chief causes of university course disenrollment. Most of the studies and tests on academic stress have been conducted in research labs or controlled environments, but these tests can not be extended to a real academic environment due to their complexity. Academic stress presents different associated symptoms, anxiety being one of the most common. This study focuses on anxiety derived from academic activities. This study aims to validate the following hypothesis: by using a non-contact method based on the use of remote photoplethysmography (rPPG), it is possible to identify academic stress levels with an accuracy greater than or equal to that of previous works which used contact methods. rPPG signals from 56 first-year engineering undergraduate students were recorded during an experimental task. The results show that the rPPG signals combined with students' demographic data and psychological scales (the State-Trait Anxiety Inventory) improve the accuracy of different classification methods. Moreover, the results demonstrate that the proposed method provides 96% accuracy by using K-nearest neighbors, J48, and random forest classifiers. The performance metrics show better or equal accuracy compared to other contact methods. In general, this study demonstrates that it is possible to implement a low-cost method for identifying academic stress levels in educational environments.


Assuntos
Fotopletismografia , Estudantes , Ansiedade , Análise por Conglomerados , Humanos , Fotopletismografia/métodos , Estudantes/psicologia
11.
Sensors (Basel) ; 21(24)2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34960343

RESUMO

The fetal autonomic nervous system responds to uterine contractions during active labor as identified by changes in the accelerations and decelerations of fetal heart rate (FHR). Thus, this exploratory study aimed to characterize the asymmetry differences of beat-to-beat FHR accelerations and decelerations in preterm and term fetuses during active labor. In an observational study, we analyzed 10 min of fetal R-R series collected from women during active preterm labor (32-36 weeks of pregnancy, n = 17) and active term labor (38-40 weeks of pregnancy, n = 27). These data were used to calculate the Deceleration Reserve (DR), which is a novel parameter that quantifies the asymmetry of the average acceleration and deceleration capacity of the heart. In addition, relevant multiscale asymmetric indices of FHR were also computed. Lower values of DR, calculated with the input parameters of T = 50 and s = 10, were associated with labor occurring at the preterm condition (p = 0.0131). Multiscale asymmetry indices also confirmed significant (p < 0.05) differences in the asymmetry of FHR. Fetuses during moderate premature labor may experience more decaying R-R trends and a lower magnitude of decelerations compared to term fetuses. These differences of FHR dynamics might be related to the immaturity of the fetal cardiac autonomic nervous system as identified by this system response to the intense uterine activity at active labor.


Assuntos
Frequência Cardíaca Fetal , Trabalho de Parto , Aceleração , Sistema Nervoso Autônomo , Desaceleração , Feminino , Frequência Cardíaca , Humanos , Recém-Nascido , Gravidez
12.
FEMS Yeast Res ; 20(7)2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32945857

RESUMO

Ustilago maydis is a Basidiomycota fungus, in which very little is known about its mechanisms of cell survival and death. To date, only the role of metacaspase1, acetate and hydrogen peroxide as inducers of cell death has been investigated. In the present work, we analyzed the lifespan of U. maydis compared with other species like Sporisorium reilianum, Saccharomyces cerevisiae and Yarrowia lipolytica, and we observed that U. maydis has a minor lifespan. We probe the addition of low concentrations metformin and curcumin to the culture media, and we observed that both prolonged the lifespan of U. maydis, a result observed for the first time in a phytopathogen fungus. However, higher concentrations of curcumin were toxic for the cells, and interestingly induced the yeast-to-mycelium dimorphic transition. The positive effect of metformin and curcumin appears to be related to an inhibition of the mechanistic Target of Rapamycin (mTOR) pathway, increase expression of autophagy genes and reducing of reactive oxygen species. These data indicate that U. maydis may be a eukaryotic model organism to elucidate the molecular mechanism underlying apoptotic and necrosis pathways, and the lifespan increase caused by metformin and curcumin.


Assuntos
Basidiomycota/citologia , Morte Celular , Curcumina/farmacologia , Metformina/farmacologia , Basidiomycota/efeitos dos fármacos , Meios de Cultura , Viabilidade Microbiana , Espécies Reativas de Oxigênio , Saccharomyces cerevisiae , Yarrowia
13.
Arch Microbiol ; 202(1): 93-103, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31485712

RESUMO

We have described that formation of basidiocarps by Ustilago maydis requires illumination. In the current research, we have proceeded to analyze what kind of light receptors are involved in this phenomenon. Accordingly, we investigated whether the homologues of the White Collar (WC), and the phytochrome (PHY) genes played a role in this process. Mutants deficient in either one of the three U. maydis WC homologue genes (WCO1a, WCO1b, WCO2), or the phytochrome-encoding the PHY gene were obtained. Phenotypic analysis of the mutants showed that ∆wco1a mutants formed similar numbers of basidiocarps than wild-type strain, whereas ∆wco1b mutants were severely affected in basidiocarp formation when illuminated with white, blue or red light. ∆wco2 and ∆phy1 mutants did not form basidiocarps under any illumination condition. These data indicate that Wco1a is the main blue light receptor, and Wco1b may operate as a secondary blue light receptor; Phy1 is the red light receptor, and Wco2 the transcription factor that controls the photo stimulation of the genes involved in the formation of fruiting bodies. It is suggested that effectiveness of the light receptors depends on the whole structure of the complex, possibly, because their association is necessary to maintain their functional structure.


Assuntos
Carpóforos/fisiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fotorreceptores Microbianos/genética , Fotorreceptores Microbianos/metabolismo , Ustilago/fisiologia , Carpóforos/efeitos da radiação , Ustilago/genética , Ustilago/efeitos da radiação
14.
Analyst ; 145(9): 3414-3423, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32254686

RESUMO

Six essential oils were analyzed by Fourier transform ion cyclotron resonance mass spectrometry coupled to negative-ion electrospray ionization (ESI(-)/FT-ICR MS). ESI offers selective ionization of a compound's polar functional groups containing nitrogen and oxygen heteroatoms. ESI in negative-ion mode allows the identification of the acidic compounds. The results showed that the samples contain between 1100-3600 individual molecular compositions, which corresponds to the greatest number of species detected to date in essential oils obtained from aromatic plant material. The compositions cover a mass range between m/z 150-500 with up to 41 carbon atoms. The dominant organic constituents of the essential oils correspond to species incorporating 2-5 oxygen atoms, detected as deprotonated/sodiated/chlorinated species. A set of 580 molecular assignments were found in common across all the samples and for the first time, a set of unique molecular systems were identified, and up to 1373 species as a unique composition for each essential oil. The molecular distributions plotted in van Krevelen diagrams (classified by their H/C vs. O/C values) suggest the presence of species with long alkyl chains and low numbers of rings plus double bonds.

15.
Int J Mol Sci ; 22(1)2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33375157

RESUMO

Dendroctonus-bark beetles are natural agents contributing to vital processes in coniferous forests, such as regeneration, succession, and material recycling, as they colonize and kill damaged, stressed, or old pine trees. These beetles spend most of their life cycle under stem and roots bark where they breed, develop, and feed on phloem. This tissue is rich in essential nutrients and complex molecules such as starch, cellulose, hemicellulose, and lignin, which apparently are not available for these beetles. We evaluated the digestive capacity of Dendroctonusrhizophagus to hydrolyze starch. Our aim was to identify α-amylases and characterize them both molecularly and biochemically. The findings showed that D. rhizophagus has an α-amylase gene (AmyDr) with a single isoform, and ORF of 1452 bp encoding a 483-amino acid protein (53.15 kDa) with a predicted signal peptide of 16 amino acids. AmyDr has a mutation in the chlorine-binding site, present in other phytophagous insects and in a marine bacterium. Docking analysis showed that AmyDr presents a higher binding affinity to amylopectin compared to amylose, and an affinity binding equally stable to calcium, chlorine, and nitrate ions. AmyDr native protein showed amylolytic activity in the head-pronotum and gut, and its recombinant protein, a polypeptide of ~53 kDa, showed conformational stability, and its activity is maintained both in the presence and absence of chlorine and nitrate ions. The AmyDr gene showed a differential expression significantly higher in the gut than the head-pronotum, indicating that starch hydrolysis occurs mainly in the midgut. An overview of the AmyDr gene expression suggests that the amylolytic activity is regulated through the developmental stages of this bark beetle and associated with starch availability in the host tree.


Assuntos
Besouros/metabolismo , Trato Gastrointestinal/metabolismo , Pinus/parasitologia , Casca de Planta/parasitologia , Amido/metabolismo , alfa-Amilases/metabolismo , Amilopectina/metabolismo , Amilose/metabolismo , Animais , Ligação Competitiva , Besouros/enzimologia , Besouros/genética , Trato Gastrointestinal/enzimologia , Regulação Enzimológica da Expressão Gênica , Hidrólise , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Ligação Proteica , alfa-Amilases/genética
16.
Entropy (Basel) ; 22(8)2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-33286569

RESUMO

Phase Entropy (PhEn) was recently introduced for evaluating the nonlinear features of physiological time series. PhEn has been demonstrated to be a robust approach in comparison to other entropy-based methods to achieve this goal. In this context, the present study aimed to analyze the nonlinear features of raw electrohysterogram (EHG) time series collected from women at the third trimester of pregnancy (TT) and later during term active parturition (P) by PhEn. We collected 10-min longitudinal transabdominal recordings of 24 low-risk pregnant women at TT (from 35 to 38 weeks of pregnancy) and P (>39 weeks of pregnancy). We computed the second-order difference plots (SODPs) for the TT and P stages, and we evaluated the PhEn by modifying the k value, a coarse-graining parameter. Our results pointed out that PhEn in TT is characterized by a higher likelihood of manifesting nonlinear dynamics compared to the P condition. However, both conditions maintain percentages of nonlinear series higher than 66%. We conclude that the nonlinear features appear to be retained for both stages of pregnancy despite the uterine and cervical reorganization process that occurs in the transition from the third trimester to parturition.

17.
Int J Mol Sci ; 20(16)2019 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-31426479

RESUMO

Bark beetles commonly produce de novo terpenoid pheromones using precursors synthesized through the mevalonate pathway. This process is regulated by Juvenile Hormone III (JH III). In this work, the expression levels of mevalonate pathway genes were quantified after phloem feeding-to induce the endogenous synthesis of JH III-and after the topical application of a JH III solution. The mevalonate pathway genes from D. rhizophagus were cloned, molecularly characterized, and their expression levels were quantified. Also, the terpenoid compounds produced in the gut were identified and quantified by Gas Chromatography Mass Spectrometry (GC-MS). The feeding treatment produced an evident upregulation, mainly in acetoacetyl-CoA thiolase (AACT), 3-hydroxy-3-methylglutaryl-CoA synthase (HMGS), 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR), phosphomevalonate kinase (PMK), and isopentenyl diphosphate isomerase (IPPI) genes, and males reached higher expression levels compared to females. In contrast, the JH III treatment did not present a clear pattern of upregulation in any sex or time. Notably, the genes responsible for the synthesis of frontalin and ipsdienol precursors (geranyl diphosphate synthase/farnesyl diphosphate synthase (GPPS/FPPS) and geranylgeranyl diphosphate synthase (GGPPS)) were not clearly upregulated, nor were these compounds further identified. Furthermore, trans-verbenol and myrtenol were the most abundant compounds in the gut, which are derived from an α-pinene transformation rather than de novo synthesis. Hence, the expression of mevalonate pathway genes in D. rhizophagus gut is not directed to the production of terpenoid pheromones, regardless of their frequent occurrence in the genus Dendroctonus.


Assuntos
Ingestão de Alimentos , Regulação da Expressão Gênica , Redes e Vias Metabólicas/genética , Feromônios/biossíntese , Gorgulhos/genética , Animais , Feminino , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/fisiologia , Hidroximetilglutaril-CoA Redutases/genética , Hidroximetilglutaril-CoA Redutases/metabolismo , Masculino , Ácido Mevalônico/metabolismo , Terpenos/metabolismo , Gorgulhos/enzimologia , Gorgulhos/metabolismo , Gorgulhos/fisiologia
18.
FEMS Yeast Res ; 18(4)2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29648589

RESUMO

The walls of both, yeast and mycelial cells of Candida albicans possess a species-specific antigen that is recognized by a monoclonal antibody (MAb 3H8). This antigen can be extracted in the form of a very high Mr complex, close or over 106 Da, by treatment, with ß-1,3-glucanase, ß mercaptoethanol or dithothreitol, or mild alkali, but not by saturated hydrogen fluoride (HF) in pyridine, suggesting that the complex is bound to wall ß-1,3 glucans, and to proteins by disulfide bonds, but not to ß-1,6 glucans. Through its sensitivity to trypsin and different deglycosylation procedures, it was concluded that the epitope is associated to a glycoprotein containing N-glycosidic, but not O-glycosidic mannan moieties. By means of electrophoresis in polycrylamide gradient gels, followed by mass spectrometric analysis, the epitope was pinpointed to a very high MW complex containing Agglutinin-Like Sequence (ALS) family proteins, and other cytoplasmic, membrane and secreted proteins. The components of this complex are bound by unknown covalent bonds. The material extracted with ß mercaptoethanol or dilute alkali appeared under the electron microscope as large aggregates in the form of spheroidal and mostly web-like structures of large sizes. These, and additional data, suggest that this protein complex may constitute an important part of the basic glycoprotein structure of C. albicans. The possibility that similar complexes exist in the wall of other fungi is an attractive, although yet untested possibility.


Assuntos
Antígenos de Fungos/análise , Candida albicans/química , Parede Celular/química , Substâncias Macromoleculares/análise , Anticorpos Antifúngicos/imunologia , Anticorpos Monoclonais/imunologia , Antígenos de Fungos/química , Antígenos de Fungos/imunologia , Antígenos de Fungos/metabolismo , Eletroforese em Gel de Poliacrilamida , Substâncias Macromoleculares/química , Substâncias Macromoleculares/imunologia , Substâncias Macromoleculares/metabolismo , Espectrometria de Massas , Microscopia Eletrônica
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