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Bacterial growing resistance to antibiotics poses a critical threat to global health. This study investigates, for the first time, the antibiofilm properties of Vicia ervilia agglutinin (VEA) from six different V. ervilia accessions against pathogenic bacteria, and the yeast Candida albicans. In the absence of antimicrobial properties, purified VEA significantly inhibited biofilm formation, both in Gram-positive and Gram-negative bacteria, but not in C. albicans. With an inhibitory concentration ranging from 100 to 500 µg/ml, the VEA antibiofilm activity was more relevant against the Gram-positive bacteria Streptococcus aureus and Staphylococcus epidermidis, whose biofilm was reduced up to 50% by VEA purified from accessions #5 and #36. VEA antibiofilm variability between accessions was observed, likely due to co-purified small molecules rather than differences in VEA protein sequences. In conclusion, VEA seed extracts from the accessions with the highest antibiofilm activity could represent a valid approach for the development of an effective antibiofilm agent.
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Antibacterianos , Biofilmes , Candida albicans , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Testes de Sensibilidade Microbiana , Biofilmes/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Candida albicans/fisiologia , Antibacterianos/farmacologia , Lectinas de Plantas/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Sementes/químicaRESUMO
Pseudogamous apomixis in Paspalum simplex generates seeds with embryos genetically identical to the mother plant and endosperms deviating from the canonical 2(maternal):1(paternal) parental genome contribution into a maternal excess 4m:1p genome ratio. In P. simplex, the gene homologous to that coding for subunit 3 of the ORIGIN OF RECOGNITION COMPLEX (PsORC3) exists in three isogenic forms: PsORC3a is apomixis specific and constitutively expressed in developing endosperm whereas PsORCb and PsORCc are up-regulated in sexual endosperms and silenced in apomictic ones. This raises the question of how the different arrangement and expression profiles of these three ORC3 isogenes are linked to seed development in interploidy crosses generating maternal excess endosperms. We demonstrate that down-regulation of PsORC3b in sexual tetraploid plants is sufficient to restore seed fertility in interploidy 4n×2n crosses and, in turn, its expression level at the transition from proliferating to endoreduplication endosperm developmental stages dictates the fate of these seeds. Furthermore, we show that only when being maternally inherited can PsORC3c up-regulate PsORC3b. Our findings lay the basis for an innovative route-based on ORC3 manipulation-to introgress the apomictic trait into sexual crops and overcome the fertilization barriers in interploidy crosses.
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Endosperma , Paspalum , Endosperma/genética , Paspalum/genética , Sementes/genéticaRESUMO
In tonal music, musical tension is strongly associated with musical expression, particularly with expectations and emotions. Most listeners are able to perceive musical tension subjectively, yet musical tension is difficult to be measured objectively, as it is connected with musical parameters such as rhythm, dynamics, melody, harmony, and timbre. Musical tension specifically associated with melodic and harmonic motion is called tonal tension. In this article, we are interested in perceived changes of tonal tension over time for chord progressions, dubbed tonal tension profiles. We propose an objective measure capable of capturing tension profile according to different tonal music parameters, namely, tonal distance, dissonance, voice leading, and hierarchical tension. We performed two experiments to validate the proposed model of tonal tension profile and compared against Lerdahl's model and MorpheuS across 12 chord progressions. Our results show that the considered four tonal parameters contribute differently to the perception of tonal tension. In our model, their relative importance adopts the following weights, summing to unity: dissonance (0.402), hierarchical tension (0.246), tonal distance (0.202), and voice leading (0.193). The assumption that listeners perceive global changes in tonal tension as prototypical profiles is strongly suggested in our results, which outperform the state-of-the-art models.
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The ability to form biofilms of pathogenic microorganisms in a wide variety of environments, surfaces and conditions constitute an important risk, both for the food industry and for public health. The aim of this work was to evaluate and to compare the effects of the methodology applied and the culture medium used on the ability of a non-O157 verotoxigenic Escherichia coli strain and an enteropathogenic strain to form biofilm on polystyrene surface. Two methodological variants were tested in static culture and culture mediums with different composition were used. The results showed that both strains were able to form a greater biofilm under culture in LB supplemented with glucose, with medium replacement at 24h and the quantification of the biofilm carried out at 48h of incubation. These conditions could be used in future studies on biofilm formation.
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Biofilmes/efeitos dos fármacos , Meios de Cultura/farmacologia , Escherichia coli Enteropatogênica/efeitos dos fármacos , Escherichia coli Shiga Toxigênica/efeitos dos fármacos , Técnicas Bacteriológicas , Biofilmes/crescimento & desenvolvimento , Escherichia coli Enteropatogênica/patogenicidade , Escherichia coli Enteropatogênica/fisiologia , Glucose/farmacologia , Poliestirenos , Escherichia coli Shiga Toxigênica/patogenicidade , Escherichia coli Shiga Toxigênica/fisiologia , Especificidade da EspécieRESUMO
1. Omarigliptin (MARIZEV®) is a once-weekly DPP-4 inhibitor approved in Japan for the treatment of type 2 diabetes. The objective of this study was to investigate the absorption, metabolism and excretion of omarigliptin in humans. 2. Six healthy subjects received a single oral dose of 25 mg (2.1 µCi) [14 C]omarigliptin. Blood, plasma, urine and fecal samples were collected at various intervals for up to 20 days post-dose. Radioactivity levels in excreta and plasma/blood samples were determined by accelerator mass spectrometry (AMS). 3. [14 C]Omarigliptin was rapidly absorbed, with peak plasma concentrations observed at 0.5-2 h post-dose. The majority of the radioactivity was recovered in urine (â¼74.4% of the dose), with less recovered in feces (â¼3.4%), suggesting the compound was well absorbed. 4. Omarigliptin was the major component in urine (â¼89% of the urinary radioactivity), indicating renal excretion of the unchanged drug as the primary clearance mechanism. Omarigliptin accounted for almost all the circulating radioactivity in plasma, with no major metabolites detected. 5. The predominantly renal elimination pathway, combined with the fact that omarigliptin is not a substrate of key drug transporters, suggest omarigliptin is unlikely to be subject to pharmacokinetic drug-drug interactions with other commonly prescribed agents.
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Isótopos de Carbono , Inibidores da Dipeptidil Peptidase IV , Compostos Heterocíclicos com 2 Anéis , Piranos , Administração Oral , Adulto , Isótopos de Carbono/administração & dosagem , Isótopos de Carbono/farmacocinética , Inibidores da Dipeptidil Peptidase IV/administração & dosagem , Inibidores da Dipeptidil Peptidase IV/farmacocinética , Compostos Heterocíclicos com 2 Anéis/administração & dosagem , Compostos Heterocíclicos com 2 Anéis/farmacocinética , Humanos , Masculino , Piranos/administração & dosagem , Piranos/farmacocinéticaRESUMO
The automatic generation of music is an emergent field of research that has attracted the attention of countless researchers. As a result, there is a broad spectrum of state of the art research in this field. Many systems have been designed to facilitate collaboration between humans and machines in the generation of valuable music. This research proposes an intelligent system that generates melodies under the supervision of a user, who guides the process through a mechanical device. The mechanical device is able to capture the movements of the user and translate them into a melody. The system is based on a Case-Based Reasoning (CBR) architecture, enabling it to learn from previous compositions and to improve its performance over time. The user uses a device that allows them to adapt the composition to their preferences by adjusting the pace of a melody to a specific context or generating more serious or acute notes. Additionally, the device can automatically resist some of the user's movements, this way the user learns how they can create a good melody. Several experiments were conducted to analyze the quality of the system and the melodies it generates. According to the users' validation, the proposed system can generate music that follows a concrete style. Most of them also believed that the partial control of the device was essential for the quality of the generated music.
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Background: : Understanding parental barriers is crucial to promote active commuting to school since the parental perceptions influence how young people commute. This study examined parental barriers to active commuting to school among Spanish children and adolescents, and their association with their gender and the usual mode of commuting. Parents of children ( n = 628) and parents of adolescents ( n = 151) from Granada (Spain) completed a paper-based questionnaire about perceived parental barriers to active commuting to school and mode of commuting. Data were analyzed using the Chi-square test. Among Spanish parents, the most common barriers reported by parents of children were traffic volume and dangerous intersections, whereas the most frequent barriers reported by parents of adolescents were distance to school and dangerous intersections. Compared to parents of children, a greater proportion of parents of adolescents reported distance to school and crime and smaller proportion reported traffic volume as barriers to active commuting to school. Among parents of children, crime was a more commonly reported as a barrier by parents of girls. Although some barriers reported by parents of passive commuters were similar for children and adolescents (such as distance to school and absence of a policeman at crosswalks), other barriers were specific to parents of children. The main parental barriers to active commuting in children were traffic volume and dangerous intersections whereas for adolescents were distance and dangerous intersections. Among Spanish parents, parental barriers to active commuting are influenced by children's age, gender and mode of commuting to school.
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Pais/psicologia , Meios de Transporte , Adolescente , Criança , Feminino , Humanos , Masculino , Segurança , Instituições Acadêmicas/estatística & dados numéricos , Espanha/epidemiologia , Inquéritos e Questionários , Meios de Transporte/estatística & dados numéricos , CaminhadaRESUMO
Cornelia de Lange Syndrome (CdLS) is an autosomal dominant (NIPBL, SMC3, and RAD21) or X-linked (SMC1A and HDAC8) disorder, characterized by distinctive craniofacial appearance, growth retardation, intellectual disability, and limb anomalies. In 2005, the Spanish CdLS Reference Center was started and now we have more than 270 cases in our database. In this special issue, we describe some of the unique or atypical patients studied by our group, whose clinical features have contributed to the expansion of the CdLS classical phenotype, helping clinicians to diagnose it. We include the case of a male with unilateral tibial hypoplasia and peroneal agenesis who had a mutation in NIPBL; we also describe one patient with a mutation in NIPBL and somatic mosaicism identified by new generation sequencing techniques; we also include one patient with CdLS and Turner syndrome; and last, an interesting patient with a duplication of the SMC1A gene. Finally, we make a short review of the splicing mutations we have found in NIPBL regarding the new knowledge on the physiological variants of the gene. © 2016 Wiley Periodicals, Inc.
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Síndrome de Cornélia de Lange/genética , Proteínas de Ciclo Celular , Síndrome de Cornélia de Lange/diagnóstico , Síndrome de Cornélia de Lange/patologia , Estudos de Associação Genética , Humanos , Masculino , Proteínas/genética , EspanhaRESUMO
Apomixis in plants consists of asexual reproduction by seeds. Here we characterized at structural and functional levels an apomixis-linked sequence of Paspalum simplex homologous to subunit 3 of the ORIGIN RECOGNITION COMPLEX (ORC3). ORC is a multiprotein complex which controls DNA replication and cell differentiation in eukaryotes. Three PsORC3 copies were identified, each one characterized by a specific expression profile. Of these, PsORC3a, specific for apomictic genotypes, is a pseudogene that was poorly and constitutively expressed in all developmental stages of apomictic flowers, whereas PsORC3b, the putative functional gene in sexual flowers, showed a precise time-related regulation. Sense transcripts of PsORC3 were expressed in the female cell lineage of both apomictic and sexual reproductive phenotypes, and in aposporous initials. Although strong expression was detected in sexual early endosperm, no expression was present in the apomictic endosperm. Antisense PsORC3 transcripts were revealed exclusively in apomictic germ cell lineages. Defective orc3 mutants of rice and Arabidopsis showed normal female gametophytes although the embryo and endosperm were arrested at early phases of development. We hypothesize that PsORC3a is associated with the down-regulation of its functional homolog and with the development of apomictic endosperm which deviates from the canonical 2(maternal):1(paternal) genome ratio.
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Apomixia/genética , Inativação Gênica , Paspalum/genética , Pseudogenes , Homologia de Sequência do Ácido Nucleico , Arabidopsis/genética , Sequência de Bases , Mapeamento Cromossômico , Clonagem Molecular , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Hibridização In Situ , Mutação/genética , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodução/genética , Alinhamento de Sequência , Transcrição GênicaRESUMO
This study evaluated the safety, tolerability, and pharmacokinetics of a posaconazole i.v. (intravenous) solution. This was a single-center, 2-part, randomized, rising single- and multiple-dose study in healthy adults. In part 1, subjects received 0 (vehicle), 50, 100, 200, 250, or 300 mg posaconazole in a single dose i.v. by 30-min peripheral infusion (6 cohorts of 12 subjects each [9 active and 3 placebo], making a total of 72 subjects). Blood samples were collected until 168 h postdose. In part 2, subjects were to receive 2 peripheral infusions at a 12-h interval on day 1 followed by once-daily infusion for 9 days. However, part 2 was terminated early because of high rates of infusion site reactions with multiple dosing at the same infusion site. The pharmacokinetics results for part 1 (n=45 subjects) showed that the mean posaconazole exposure (area under the concentration-time curve from time zero to infinity [AUC0-∞]) ranged from 4,890 to 46,400 ng · h/ml (range of coefficient of variation values, 26 to 50). The dose-proportionality slope estimate (90% confidence interval) for AUC0-∞ was 1.30 (1.19 to 1.41), indicating a greater-than-dose-proportional increase. The data for safety in part 1 show that 29/72 subjects had ≥1 adverse event. Infusion site reactions were reported in 2/9 vehicle subjects, 0/18 placebo subjects, and 7/45 i.v. posaconazole subjects. The data for safety in part 2 show that infusion site reactions were reported in 1/4 (25%) placebo subjects, 3/9 (33%) vehicle control subjects, and 4/5 (80%) i.v. posaconazole (100 mg) subjects (3 posaconazole recipients subsequently developed thrombophlebitis and were discontinued from treatment). In conclusion, the posaconazole i.v. solution showed a greater-than-dose-proportional increase in exposure, primarily at doses below 200 mg. When administered peripherally at the same infusion site, multiple dosing of i.v. posaconazole led to unacceptably high rates of infusion site reactions. Intravenous posaconazole was otherwise well tolerated. Single doses of i.v. posaconazole were tolerated when given through a peripheral vein over 30 min.
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Antifúngicos/efeitos adversos , Antifúngicos/farmacocinética , Triazóis/efeitos adversos , Triazóis/farmacocinética , Adolescente , Adulto , Idoso , Antifúngicos/administração & dosagem , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Voluntários Saudáveis , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Triazóis/administração & dosagem , Adulto JovemRESUMO
OBJECTIVES: To evaluate the lipid-altering efficacy and safety of ezetimibe monotherapy in young children with heterozygous familial hypercholesterolemia (HeFH) or nonfamilial hypercholesterolemia (nonFH). STUDY DESIGN: One hundred thirty-eight children 6-10 years of age with diagnosed HeFH or clinically important nonFH (low-density lipoprotein cholesterol [LDL-C] ≥ 160 mg/dL [4.1 mmol/L]) were enrolled into a multicenter, 12-week, randomized, double-blind, placebo-controlled study. Following screening/drug washout and a 5-week single-blind placebo-run-in with diet stabilization, subjects were randomized 2:1 to daily ezetimibe 10 mg (n = 93) or placebo (n = 45) for 12 weeks. Lipid-altering efficacy and safety were assessed in all treated patients. RESULTS: Overall, mean age was 8.3 years, 57% were girls, 80% were white, mean baseline LDL-C was 228 mg/dL (5.9 mmol/L), and 91% had HeFH. After 12 weeks, ezetimibe significantly reduced LDL-C by 27% after adjustment for placebo (P < .001) and produced significant reductions in total cholesterol (21%), nonhigh-density lipoprotein cholesterol (26%), and apolipoprotein B (20%) (P < .001 for all). LDL-C lowering response in sex, race, baseline lipids, and HeFH/nonFH subgroups was generally consistent with overall study results. Ezetimibe was well tolerated, with a safety profile similar to studies in older children, adolescents, and adults. CONCLUSIONS: Ezetimibe monotherapy produced clinically relevant reductions in LDL-C and other key lipid variables in young children with primary HeFH or clinically important nonFH, with a favorable safety/tolerability profile. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00867165.
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Anticolesterolemiantes/uso terapêutico , Azetidinas/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Anticolesterolemiantes/efeitos adversos , Azetidinas/efeitos adversos , Criança , Método Duplo-Cego , Ezetimiba , Feminino , Heterozigoto , Humanos , Hipercolesterolemia/genética , Masculino , Método Simples-Cego , Resultado do TratamentoRESUMO
Capillary electrophoresis was used for the rapid determination of three chemotherapeutic drugs employed to treat colorectal cancer: irinotecan, tegafur, and leucovorin, and their main metabolites (7-ethyl-10-hydroxycamptothecin and 5-fluorouracil), in human urine samples. A phosphate buffer (pH 11.34; 20 mM) was selected as the background electrolyte. A hydrodynamic injection (9 s, 30 mbar) was applied and the separation was carried out using a separation temperature and voltage of 25°C and 25 kV, respectively. A capillary with two detection windows for serial online UV and fluorescence detection was satisfactorily employed. A solid-supported liquid-liquid extraction procedure was optimized for the clean-up of the urine samples and the extraction of the analytes. Matrix effects were assessed and signal suppression was observed for three of the analytes, thus, matrix-matched calibration was used for compensating residual matrix effects on these analytes. The proposed method allows the separation and quantification of the chemotherapeutics in less than 6 min. Detection limits range between 0.01 and 0.30 mg/L. The method was satisfactorily applied to the determination of the target compounds in human urine samples, with recoveries of 92.4-107.7%.
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Antineoplásicos/urina , Eletroforese Capilar/métodos , Extração Líquido-Líquido , Espectrometria de Fluorescência/métodos , Espectrofotometria Ultravioleta/métodos , HumanosRESUMO
Ubiquitin is a tag that often initiates degradation of proteins by the proteasome in the ubiquitin proteasome system. Targeted expression of K6W mutant ubiquitin (K6W-Ub) in the lens results in defects in lens development and cataract formation, suggesting critical functions for ubiquitin in lens. To study the developmental processes that require intact ubiquitin, we executed the most extensive characterization of the lens proteome to date. We quantified lens protein expression changes in multiple replicate pools of P1 wild-type and K6W-Ub-expressing mouse lenses. Lens proteins were digested with trypsin, peptides were separated using strong cation exchange and reversed-phase liquid chromatography, and tandem mass (MS/MS) spectra were collected with a linear ion trap. Transgenic mice that expressed low levels of K6W-Ub (low expressers) had normal, clear lenses at birth, whereas the lenses that expressed high levels of K6W-Ub (higher expressers) had abnormal lenses and cataracts at birth. A total of 2052 proteins were identified, of which 996 were reliably quantified and compared between wild-type and K6W-Ub transgenic mice. Consistent with a delayed developmental program, fiber-cell-specific proteins, such as γ-crystallins (γA, γB, γC, and γE), were down-regulated in K6W-Ub higher expressers. Up-regulated proteins were involved in energy metabolism, signal transduction, and proteolysis. The K6W-Ub low expressers exhibited delayed onset and milder cataract consistent with smaller changes in protein expression. Because lens protein expression changes occurred prior to lens morphological abnormalities and cataract formation in K6W-Ub low expressers, it appears that expression of K6W-Ub sets in motion a process of altered protein expression that results in developmental defects and cataract.
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Catarata/genética , Proteínas do Olho/genética , Regulação da Expressão Gênica no Desenvolvimento , Cristalino/metabolismo , Proteoma/genética , Ubiquitina/genética , Substituição de Aminoácidos , Animais , Animais Recém-Nascidos , Catarata/metabolismo , Catarata/patologia , Proteínas do Olho/metabolismo , Perfilação da Expressão Gênica , Cristalino/patologia , Lisina/metabolismo , Camundongos , Camundongos Transgênicos , Mutagênese Sítio-Dirigida , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteoma/metabolismo , Triptofano/metabolismo , Ubiquitina/metabolismoRESUMO
This was a phase 1B, dose-ranging, multicenter, pharmacokinetics, and safety study of cyclodextrin-based posaconazole intravenous (i.v.) solution administered through a central line to subjects at high risk for invasive fungal disease (part 1 of a 2-part study [phase 1B/3]). Initially, the safety and tolerability of single-dose posaconazole i.v. 200 mg (n = 10) were compared with those of a placebo (n = 11). Subsequently, 2 doses were evaluated, posaconazole i.v. 200 mg once daily (q.d.) (n = 21) and 300 mg q.d. (n = 24). The subjects received twice-daily (b.i.d.) posaconazole i.v. on day 1, followed by 13 days of posaconazole i.v. q.d., then 14 days of posaconazole oral suspension 400 mg b.i.d. The steady-state (day 14) exposure target (average concentration [areas under concentration-time curve {AUCs}/24 h, average concentrations at steady state {Cavgs}], of ≥ 500 to ≤ 2,500 ng/ml in ≥ 90% of the subjects) was achieved by 94% of the subjects for 200 mg posaconazole q.d. and by 95% of subjects for 300 mg posaconazole q.d. The desired exposure target (mean steady-state Cavg, â¼ 1,200 ng/ml) was 1,180 ng/ml in the 200-mg dosing cohort and was exceeded in the 300-mg dosing cohort (1,430 ng/ml). Posaconazole i.v. was well tolerated. Posaconazole i.v. 300 mg q.d. was selected for the phase 3 study segment. (This study has been registered at ClinicalTrials.gov under registration no. NCT01075984.).
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Antifúngicos/efeitos adversos , Antifúngicos/farmacocinética , Micoses/metabolismo , Triazóis/efeitos adversos , Triazóis/farmacocinética , Adulto , Idoso , Antifúngicos/administração & dosagem , Estudos de Coortes , Relação Dose-Resposta a Droga , Feminino , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Soluções Farmacêuticas , Triazóis/administração & dosagemRESUMO
Apomixis, a clonal plant reproduction by seeds, is controlled in Paspalum spp. by a single locus which is blocked in terms of recombination. Partial sequence analysis of the apomixis locus revealed structural features of heterochromatin, namely the presence of repetitive elements, gene degeneration, and de-regulation. To test the epigenetic control of apomixis, a study on the distribution of cytosine methylation at the apomixis locus and the effect of artificial DNA demethylation on the mode of reproduction was undertaken in two apomictic Paspalum species. The 5-methylcytosine distribution in the apomixis-controlling genomic region was studied in P. simplex by methylation-sensitive restriction fragment length polymorphism (RFLP) analysis and in P. notatum by fluorescene in situ hybridization (FISH). The effect of DNA demethylation was studied on the mode of reproduction of P. simplex by progeny test analysis of apomictic plants treated with the demethylating agent 5'-azacytidine. A high level of cytosine methylation was detected at the apomixis-controlling genomic region in both species. By analysing a total of 374 open pollination progeny, it was found that artificial demethylation had little or no effect on apospory, whereas it induced a significant depression of parthenogenesis. The results suggested that factors controlling repression of parthenogenesis might be inactivated in apomictic Paspalum by DNA methylation.
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Apomixia/genética , Metilação de DNA , Epigênese Genética , Paspalum/genética , 5-Metilcitosina/metabolismo , Azacitidina/farmacologia , Cromossomos Artificiais Bacterianos/metabolismo , Metilação de DNA/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Hibridização in Situ Fluorescente , Polinização/efeitos dos fármacos , Polimorfismo de Fragmento de RestriçãoRESUMO
The Network Noisy Leaky Integrate and Fire equation is among the simplest model allowing for a self-consistent description of neural networks and gives a rule to determine the probability to find a neuron at the potential v. However, its mathematical structure is still poorly understood and, concerning its solutions, very few results are available. In the midst of them, a recent result shows blow-up in finite time for fully excitatory networks. The intuitive explanation is that each firing neuron induces a discharge of the others; thus increases the activity and consequently the discharge rate of the full network. In order to better understand the details of the phenomena and show that the equation is more complex and fruitful than expected, we analyze further the model. We extend the finite time blow-up result to the case when neurons, after firing, enter a refractory state for a given period of time. We also show that spontaneous activity may occur when, additionally, randomness is included on the firing potential VF in regimes where blow-up occurs for a fixed value of VF.
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Potenciais de Ação/fisiologia , Modelos Neurológicos , Rede Nervosa/fisiologia , Período Refratário Eletrofisiológico , Análise Numérica Assistida por ComputadorRESUMO
The primary cilium, hereafter cilium, is an antenna-like organelle that modulates intracellular responses, including autophagy, a lysosomal degradation process essential for cell homeostasis. Dysfunction of the cilium is associated with impairment of autophagy and diseases known as "ciliopathies". The discovery of autophagy-related proteins at the base of the cilium suggests its potential role in coordinating autophagy initiation in response to physiopathological stimuli. One of these proteins, beclin-1 (BECN1), it which is necessary for autophagosome biogenesis. Additionally, polycystin-2 (PKD2), a calcium channel enriched at the cilium, is required and sufficient to induce autophagy in renal and cancer cells. We previously demonstrated that PKD2 and BECN1 form a protein complex at the endoplasmic reticulum in non-ciliated cells, where it initiates autophagy, but whether this protein complex is present at the cilium remains unknown. Anorexigenic pro-opiomelanocortin (POMC) neurons are ciliated cells that require autophagy to maintain intracellular homeostasis. POMC neurons are sensitive to metabolic changes, modulating signaling pathways crucial for controlling food intake. Exposure to the saturated fatty acid palmitic acid (PA) reduces ciliogenesis and inhibits autophagy in these cells. Here, we show that PKD2 and BECN1 form a protein complex in N43/5 cells, an in vitro model of POMC neurons, and that both PKD2 and BECN1 locate at the cilium. In addition, our data show that the cilium is required for PKD2-BECN1 protein complex formation and that PA disrupts the PKD2-BECN1 complex, suppressing autophagy. Our findings provide new insights into the mechanisms by which the cilium controls autophagy in hypothalamic neuronal cells.
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Autofagia , Proteína Beclina-1 , Cílios , Hipotálamo , Neurônios , Canais de Cátion TRPP , Animais , Camundongos , Proteína Beclina-1/metabolismo , Cílios/metabolismo , Hipotálamo/metabolismo , Hipotálamo/citologia , Neurônios/metabolismo , Canais de Cátion TRPP/metabolismo , Canais de Cátion TRPP/genéticaRESUMO
PURPOSE: A phase I trial of intravesical recombinant adenovirus mediated interferon-α2b gene therapy (rAd-IFNα) formulated with the excipient SCH Syn3 was conducted in patients with nonmuscle invasive bladder cancer who had disease recurrence after treatment with bacillus Calmette-Guérin. The primary objective was to determine the safety of rAd-IFNα/Syn3. Secondary end points were demonstrated effective rAd-IFNα gene expression and preliminary evidence of clinical activity at 3 months. MATERIALS AND METHODS: A total of 17 patients with recurrent nonmuscle invasive bladder cancer after bacillus Calmette-Guérin treatment were enrolled in the study. A single treatment of rAd-IFNα (3 × 10(9) to 3 × 10(11) particles per ml) formulated with the excipient Syn3 was administered. Patient safety was evaluated for 12 or more weeks. Efficacy of gene transfer was determined by urine IFNα protein concentrations. Preliminary drug efficacy was determined at 3 months. RESULTS: Intravesical rAd-IFNα/Syn3 was well tolerated as no dose limiting toxicity was encountered. Urgency was the most common adverse event and all cases were grade 1 or 2. rAd-IFNα DNA was not detected in the blood. However, transient low serum IFNα and Syn3 levels were measured. High and prolonged dose related urine IFNα levels were achieved with the initial treatment. Of the 14 patients treated at doses of 10(10) or more particles per ml with detectable urine IFNα, 6 (43%) experienced a complete response at 3 months and 2 remained disease-free at 29.0 and 39.2 months, respectively. CONCLUSIONS: Intravesical rAd-IFNα/Syn3 was well tolerated with no dose limiting toxicity encountered. Dose dependent urinary IFNα concentrations confirmed efficient gene transfer and expression. Intravesical rAd-IFNα/Syn3 demonstrated clinical activity in nonmuscle invasive bladder cancer recurring after bacillus Calmette-Guérin.
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Carcinoma de Células de Transição/terapia , Terapia Genética/métodos , Interferon-alfa/administração & dosagem , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/terapia , Neoplasias da Bexiga Urinária/terapia , Adenoviridae/genética , Administração Intravesical , Adulto , Idoso , Idoso de 80 Anos ou mais , Vacina BCG/administração & dosagem , Carcinoma de Células de Transição/mortalidade , Carcinoma de Células de Transição/patologia , Ácidos Cólicos/administração & dosagem , Dissacarídeos/administração & dosagem , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Vetores Genéticos , Humanos , Interferon alfa-2 , Interferon-alfa/genética , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Recidiva Local de Neoplasia/patologia , Prognóstico , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/genética , Medição de Risco , Análise de Sobrevida , Falha de Tratamento , Resultado do Tratamento , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologiaRESUMO
OBJECTIVES: To analyse the differences in the clinical features and characteristics of (123)I-labelled 2ß-carbomethoxy-3ß-(4-iodophenyl)-N-(3-fluoropropyl) nortropane ((123)I-FP-CIT) single photon emission CT (SPECT) imaging among patients with vascular parkinsonism (VP) and Parkinson's disease (PD). METHODS: We performed a case-control study to compare clinical features and qualitative and semi-quantitative analyses of (123)I-FP-CIT SPECT images between 106 patients with VP and 280 patients with PD. A case series study was used to search for clinical features related to SPECT or neuroimaging findings among patients with VP. RESULTS: Patients with VP had a higher age at symptom onset and lower disease duration than patients with PD. The most frequent symptom at onset was gait disorder in VP and tremor in PD. Gait disorder, postural instability and falls were more frequent in VP. Rest and mixed tremor were more prevalent in PD. Of the patients who received levodopa treatment in the VP group, only about half had a good response. Qualitatively (123)I-FP-CIT SPECT images were normal in 32.5% of patients with VP and abnormal in all patients with PD. The use of different visual score patterns showed higher ability to differentiate VP from PD. Semi-quantitative analysis showed significantly higher uptake in the striatum, caudate and putamen in VP. The asymmetry index was higher in patients with PD. Among patients with VP, falls were the only clinical feature that demonstrated a correlation with the SPECT visual pattern. CONCLUSION: Our data contribute to the confirmation that VP and PD are two different clinical entities. Neurological signs, response to treatment and qualitative and semi-quantitative (123)I-FP-CIT SPECT analyses may help to make the diagnosis.
Assuntos
Transtornos Cerebrovasculares/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Neuroimagem Funcional/métodos , Doença de Parkinson Secundária/metabolismo , Doença de Parkinson/metabolismo , Tropanos , Idoso , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Estudos de Casos e Controles , Transtornos Cerebrovasculares/diagnóstico , Transtornos Cerebrovasculares/diagnóstico por imagem , Feminino , Neuroimagem Funcional/estatística & dados numéricos , Humanos , Radioisótopos do Iodo , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson Secundária/diagnóstico , Doença de Parkinson Secundária/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricosRESUMO
BACKGROUND: Apomixis is an alternative route of plant reproduction that produces individuals genetically identical to the mother plant through seeds. Apomixis is desirable in agriculture, because it guarantees the perpetuation of superior genotypes (i.e. heterotic hybrid seeds) by self-seeding without loss of hybrid vigour. The Paspalum genus, an archetypal model system for mining apomixis gene(s), is composed of about 370 species that have extremely diverse reproductive systems, including self-incompatibility, self-fertility, full sexual reproduction, and facultative or obligate apomixis. Barriers to interspecific hybridization are relaxed in this genus, allowing the production of new hybrids from many different parental combinations. Paspalum is also tolerant to various parental genome contributions to the endosperm, allowing analyses of how sexually reproducing crop species might escape from dosage effects in the endosperm. SCOPE: In this article, the available literature characterizing apomixis in Paspalum spp. and its use in breeding is critically reviewed. In particular, a comparison is made across species of the structure and function of the genomic region controlling apomixis in order to identify a common core region shared by all apomictic Paspalum species and where apomixis genes are likely to be localized. Candidate genes are discussed, either as possible genetic determinants (including homologs to signal transduction and RNA methylation genes) or as downstream factors (such as cell-to-cell signalling and auxin response genes) depending, respectively, on their co-segregation with apomixis or less. Strategies to validate the role of candidate genes in apomictic process are also discussed, with special emphasis on plant transformation in natural apomictic species.