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Social units, such as households and schools, can play an important role in controlling epidemic outbreaks. In this work, we study an epidemic model with a prompt quarantine measure on networks with cliques (a clique is a fully connected subgraph representing a social unit). According to this strategy, newly infected individuals are detected and quarantined (along with their close contacts) with probability f. Numerical simulations reveal that epidemic outbreaks in networks with cliques are abruptly suppressed at a transition point f_{c}. However, small outbreaks show features of a second-order phase transition around f_{c}. Therefore, our model can exhibit properties of both discontinuous and continuous phase transitions. Next, we show analytically that the probability of small outbreaks goes continuously to 1 at f_{c} in the thermodynamic limit. Finally, we find that our model exhibits a backward bifurcation phenomenon.
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Epidemias , Humanos , Surtos de Doenças , Grupo Social , Quarentena , ProbabilidadeRESUMO
Streamlit is an open-source Python coding framework for building web-applications or "web-apps" and is now being used by researchers to share large data sets from published studies and other resources. Here we present Stmol, an easy-to-use component for rendering interactive 3D molecular visualizations of protein and ligand structures within Streamlit web-apps. Stmol can render protein and ligand structures with just a few lines of Python code by utilizing popular visualization libraries, currently Py3DMol and Speck. On the user-end, Stmol does not require expertise to interactively navigate. On the developer-end, Stmol can be easily integrated within structural bioinformatic and cheminformatic pipelines to provide a simple means for user-end researchers to advance biological studies and drug discovery efforts. In this paper, we highlight a few examples of how Stmol has already been utilized by scientific communities to share interactive molecular visualizations of protein and ligand structures from known open databases. We hope Stmol will be used by researchers to build additional open-sourced web-apps to benefit current and future generations of scientists.
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This study shows the effectiveness of the wastewater treatment from a municipal slaughterhouse that has undergone a previous biological treatment applying a sequence of stages, reaching a 75% of elimination of the chemical oxygen demand (COD) using sedimentation in combination with coagulation-flocculation, using 0.5 g/L FeCl3 which is one of the best known inorganic coagulants. Then, the elimination of COD was around 98% adding the Fenton process in which 1,000 mg/L H2O2 and FeSO4 were used. In addition to the COD, other water quality parameters were measured to evaluate the level of purification of the test samples, such as solids of different types, pH, DOC and so on. With the above process, it can be noted that the Fenton process produced a slight improvement in the effluent quality by using a solar concentrator in the now-called photo-Fenton process, reaching around 99% of COD removal (0.36 g/L), 91% of total suspended solids (0.32 g/L) and 89% of dissolved organic carbon (0.20 g/L). These results were the best achieved within a proposed treatment train for this type of complex wastewater. Moreover, this last part of the process adds an improvement by the usage of renewable energy sources such as sunlight.
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Eliminação de Resíduos Líquidos , Poluentes Químicos da Água , Matadouros , Catálise , Peróxido de Hidrogênio , Ferro , Oxirredução , Luz Solar , Águas Residuárias , Poluentes Químicos da Água/análiseRESUMO
An important group of antiemetic drugs used in the treatment of nausea and vomiting after chemotherapy containing an indole moiety in their structures, working as 5- hydroxytryptamine type 3 serotonin receptor antagonist (5-HT3). This study focuses on compounds bearing an indole core that present a 5-HT3 receptor antagonist activity, which have been successfully used as antiemetic drugs for reducing chemotherapy adverse secondary effects during cancer treatment. Their synthesis, biological activities, and some outstanding characteristics are discussed, providing a general outlook towards the development of more efficient antiemetic drugs.
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Antieméticos , Antineoplásicos , Preparações Farmacêuticas , Antieméticos/uso terapêutico , Antineoplásicos/uso terapêutico , Humanos , Indóis/uso terapêutico , Náusea/induzido quimicamente , Náusea/tratamento farmacológico , Receptores 5-HT3 de Serotonina/uso terapêuticoRESUMO
The function of proteins depends on specific partners that regulate protein folding, degradation and protein-protein interactions, such partners are the chaperones and cochaperones. In chloroplasts, proteins belonging to several families of chaperones have been identified: chaperonins (Cpn60s), Hsp90s (Hsp90-5/Hsp90C), Hsp100s (Hsp93/ClpC) and Hsp70s (cpHsc70s). Several lines of evidence have demonstrated that cpHsc70 chaperones are involved in molecular processes like protein import, protein folding and oligomer formation that impact important physiological aspects in plants such as thermotolerance and thylakoid biogenesis. Despite the vast amount of data existing around the function of cpHcp70s chaperones, very little attention has been paid to the roles of DnaJ and GrpE cochaperones in the chloroplast. In this study, we performed a phylogenetic analysis of the chloroplastic GrpE (CGE) proteins from 71 species. Based on their phylogenetic relationships and on a motif enrichment analysis, we propose a classification system for land plants' CGEs, which include two independent groups with specific primary structure traits. Furthermore, using in vivo assays we determined that the two CGEs from A. thaliana (AtCGEs) complement the mutant phenotype displayed by a knockout E. coli strain defective in the bacterial grpE gene. Moreover, we determined in planta that the two AtCGEs are bona fide chloroplastic proteins, which form the essential homodimers needed to establish direct physical interactions with the cpHsc70-1 chaperone. Finally, we found evidence suggesting that AtCGE1 is involved in specific physiological phenomena in A. thaliana, such as the chloroplastic response to heat stress, and the correct oligomerization of the photosynthesis-related LHCII complex.
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Arabidopsis/metabolismo , Proteínas de Cloroplastos/metabolismo , Cloroplastos/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Chaperonas Moleculares/metabolismo , Fotossíntese/fisiologiaRESUMO
To examine the growth of Candida norvegensis (strain Levazoot 15), four experiments were conducted with different sources of energy, nitrogen, vitamins, and microminerals. Optical density was used as an indirect measure of strain growth in a fully randomized factorial design, in which principal factor A was the source of energy, nitrogen, vitamins, or microminerals and principal factor B was the measurement time point (0, 20, or 40 h). The results showed that the yeast strain used glucose (primarily sucrose and lactose) as the energy source and tryptone as the nitrogen source. The addition of B-complex vitamins or microminerals was not necessary for strain growth. It is concluded that the strain Levazoot 15 preferentially utilizes glucose as a source of energy, tryptone as a source of nitrogen and manganese as a mineral source, and that no vitamin source was necessary for growth.
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Candida/crescimento & desenvolvimento , Candida/metabolismo , Glucose/metabolismo , Manganês/metabolismo , Peptonas/metabolismo , Metabolismo Energético/fisiologia , Minerais/metabolismo , Nitrogênio/metabolismo , Vitamina B 12/análogos & derivados , Vitamina B 12/metabolismo , Vitaminas/metabolismoRESUMO
BACKGROUND: In order to develop new larvicidal agents derived from phytochemicals, the larvicidal activity of fifty molecules that are constituent of essential oils was evaluated against Culex quinquefasciatus Say. Terpenes, terpenoids and phenylpropanoids molecules were included in the in vitro evaluation, and QSAR models using genetic algorithms were built to identify molecular and structural properties of biological interest. Further, to obtain structural details on the possible mechanism of action, selected compounds were submitted to docking studies on sterol carrier protein-2 (SCP-2) as possible target. RESULTS: Results showed high larvicidal activity of carvacrol and thymol on the third and fourth larval stage with a median lethal concentration (LC50) of 5.5 and 11.1 µg/mL respectively. Myrcene and carvacrol were highly toxic for pupae, with LC50 values of 31.8 and 53.2 µg/mL. Structure-activity models showed that the structural property π-bonds is the largest contributor of larvicidal activity while ketone groups should be avoided. Similarly, property-activity models attributed to the molecular descriptor LogP the most contribution to larvicidal activity, followed by the absolute total charge (Qtot) and molar refractivity (AMR). The models were statistically significant; thus the information contributes to the design of new larvicidal agents. Docking studies show that all molecules tested have the ability to interact with the SCP-2 protein, wherein α-humulene and ß-caryophyllene were the compounds with higher binding energy. CONCLUSIONS: The description of the molecular properties and the structural characteristics responsible for larvicidal activity of the tested compounds were used for the development of mathematical models of structure-activity relationship. The identification of molecular and structural descriptors, as well as studies of molecular docking on the SCP-2 protein, provide insight on the mechanism of action of the active molecules, and the information can be used for the design of new structures for synthesis as potential new larvicidal agents.
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Human immunodeficiency virus type-1 (HIV-1) has infected more than 40 million people around the world. HIV-1 treatment still has several side effects, and the development of a vaccine, which is another potential option for decreasing human infections, has faced challenges. This work presents a computational study that includes a quantitative structure activity relationship(QSAR) using density functional theory(DFT) for reported peptides to identify the principal quantum mechanics descriptors related to peptide activity. In addition, the molecular recognition properties of these peptides are explored on major histocompatibility complex I (MHC-I) through docking and molecular dynamics (MD) simulations accompanied by the Molecular Mechanics Generalized Born Surface Area (MMGBSA) approach for correlating peptide activity reported elsewhere vs. theoretical peptide affinity. The results show that the carboxylic acid and hydroxyl groups are chemical moieties that have an inverse relationship with biological activity. The number of sulfides, pyrroles and imidazoles from the peptide structure are directly related to biological activity. In addition, the HOMO orbital energy values of the total absolute charge and the Ghose-Crippen molar refractivity of peptides are descriptors directly related to the activity and affinity on MHC-I. Docking and MD simulation studies accompanied by an MMGBSA analysis show that the binding free energy without considering the entropic contribution is energetically favorable for all the complexes. Furthermore, good peptide interaction with the most affinity is evaluated experimentally for three proteins. Overall, this study shows that the combination of quantum mechanics descriptors and molecular modeling studies could help describe the immunogenic properties of peptides from HIV-1.
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Antígenos de Histocompatibilidade Classe I/química , Modelos Moleculares , Peptídeos/química , Conformação Proteica , Relação Quantitativa Estrutura-Atividade , Sítios de Ligação , HIV-1 , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Peptídeos/metabolismo , Ligação ProteicaRESUMO
Various social, financial, biological and technological systems can be modeled by interdependent networks. It has been assumed that in order to remain functional, nodes in one network must receive the support from nodes belonging to different networks. So far these models have been limited to the case in which the failure propagates across networks only if the nodes lose all their supply nodes. In this paper we develop a more realistic model for two interdependent networks in which each node has its own supply threshold, i.e., they need the support of a minimum number of supply nodes to remain functional. In addition, we analyze different conditions of internal node failure due to disconnection from nodes within its own network. We show that several local internal failure conditions lead to similar nontrivial results. When there are no internal failures the model is equivalent to a bipartite system, which can be useful to model a financial market. We explore the rich behaviors of these models that include discontinuous and continuous phase transitions. Using the generating functions formalism, we analytically solve all the models in the limit of infinitely large networks and find an excellent agreement with the stochastic simulations.
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BACKGROUND: Prevalence rates of obesity and related diseases are quickly reaching epidemic proportions among Hispanic males in the United States. Hispanic males suffer from the highest prevalence of obesity-related diseases when compared to all other racial/ethnic groups. Despite evidence showing that weight loss can significantly reduce the risk of obesity-related health implications, literature informing best practices to engage Hispanic males in weight management programs is scarce. PURPOSE: The purpose of the current study was to engage Spanish-speaking, Mexican-origin males with overweight or obesity to examine their perspectives of diet-related behaviors related to weight management. METHODS: Demographic and acculturation data were collected using questionnaires. Fourteen semistructured interviews were completed with an all-Spanish-speaking cohort of men (age: 45.0±9.8 years; BMI: 34.2±6.5 kg m-2) who were born outside of the United States. We conducted a thematic analysis using a hybrid deductive-inductive analysis strategy using a previously developed codebook that was updated during iterative analysis of interview transcripts. RESULTS: Participants reported that healthful eating habits were hindered, among other factors, by lack of knowledge, sociocultural norms and conceptualizations of masculinity. Viable diet-related intervention approaches also surfaced, including building consciousness, promotion of traditional knowledge and the integration of the family in interventions. CONCLUSION: Findings suggest that Spanish-speaking, Mexican-origin men have interest in actively engaging in behavior changes that improve their dietary habits and engage in weight management. Our findings yield valuable insights that can be used to formulate tailored intervention strategies to improve obesity prevention and treatment programs for this vulnerable subgroup.
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Comportamento Alimentar/etnologia , Comportamentos Relacionados com a Saúde/etnologia , Hispânico ou Latino/psicologia , Masculinidade , Obesidade/etnologia , Obesidade/prevenção & controle , Aculturação , Adulto , Conhecimentos, Atitudes e Prática em Saúde , Promoção da Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/psicologia , Pesquisa Qualitativa , Comportamento de Redução do Risco , Inquéritos e Questionários , Estados UnidosRESUMO
The dynamics of a mosquito population depends heavily on climatic variables such as temperature and precipitation. Since climate change models predict that global warming will impact on the frequency and intensity of rainfall, it is important to understand how these variables affect the mosquito populations. We present a model of the dynamics of a Culex quinquefasciatus mosquito population that incorporates the effect of rainfall and use it to study the influence of the number of rainy days and the mean monthly precipitation on the maximum yearly abundance of mosquitoes Mmax. Additionally, using a fracturing process, we investigate the influence of the variability in daily rainfall on Mmax. We find that, given a constant value of monthly precipitation, there is an optimum number of rainy days for which Mmax is a maximum. On the other hand, we show that increasing daily rainfall variability reduces the dependence of Mmax on the number of rainy days, leading also to a higher abundance of mosquitoes for the case of low mean monthly precipitation. Finally, we explore the effect of the rainfall in the months preceding the wettest season, and we obtain that a regimen with high precipitations throughout the year and a higher variability tends to advance slightly the time at which the peak mosquito abundance occurs, but could significantly change the total mosquito abundance in a year.
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Culicidae , Chuva , Animais , Mudança Climática , Culex , Dinâmica Populacional/tendências , Temperatura , Tempo (Meteorologia)RESUMO
Bovine respiratory disease (BRD) is the most common and economically detrimental disease of beef cattle during the postweaning period, causing the majority of morbidity and mortality in feedlots. The pathogenesis of this disease often includes an initial viral infection, which can predispose cattle to a secondary bacterial infection. The objective of this experiment was to determine the effects of timing of an intratracheal (MH) challenge relative to 72 h of natural exposure to bovine viral diarrhea virus (BVDV) type 1b persistently infected (PI) calves on performance, serum antibody production, total and differential white blood cell (WBC) count, rectal temperature, clinical severity score (CS), and haptoglobin (Hp). Steers ( = 24; 276 ± 31 kg initial BW) were randomly allocated to 1 of 3 treatments (8 steers/treatment) in a randomized complete block design. Treatments were steers not exposed to calves PI with BVDV 1b and not challenged with MH (CON), steers intratracheally challenged with MH 84 h after being exposed to calves PI with BVDV 1b for 72 h (LateCh), and steers intratracheally challenged with MH 12 h after being exposed to calves PI with BVDV 1b for 72 h (EarlyCh). Performance (ADG, DMI, and G:F) was decreased ( < 0.001) for both EarlyCh and LateCh from d 0 to 4. From d 5 to 17, LateCh appeared to compensate for this lost performance and demonstrated increased ADG ( = 0.01) and G:F ( = 0.01) compared with EarlyCh. Both EarlyCh and LateCh had decreased platelet counts ( < 0.001) compared with CON. Antibody concentrations of BVDV and MH were higher ( < 0.05) for both EarlyCh and LateCh compared with CON. Rectal temperature, CS, and Hp increased ( < 0.001) across time from h 4 to 48, h 4 to 36, and h 8 to 168, respectively. Within 24 h of MH challenge, WBC and neutrophil concentrations within the blood increased whereas lymphocyte concentrations decreased. The timing of BVDV exposure relative to a MH challenge appears to influence the CS and acute phase response associated with BRD. As typical beef cattle marketing channels allow for variation in the timing of respiratory pathogen exposure, understanding the physiological changes in morbid cattle will lead to improved management of BRD.
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Doença das Mucosas por Vírus da Diarreia Viral Bovina/imunologia , Bovinos/fisiologia , Vírus da Diarreia Viral Bovina Tipo 1/imunologia , Mannheimia haemolytica/imunologia , Infecções por Pasteurellaceae/veterinária , Animais , Temperatura Corporal , Doença das Mucosas por Vírus da Diarreia Viral Bovina/complicações , Doença das Mucosas por Vírus da Diarreia Viral Bovina/metabolismo , Doença das Mucosas por Vírus da Diarreia Viral Bovina/virologia , Bovinos/imunologia , Haptoglobinas/análise , Haptoglobinas/metabolismo , Masculino , Infecções por Pasteurellaceae/complicações , Infecções por Pasteurellaceae/imunologia , Infecções por Pasteurellaceae/microbiologia , Distribuição Aleatória , Carne Vermelha , Fatores de TempoRESUMO
Novel chalcone derivatives with different substituents attached to A and B-rings: hydroxyl, methoxyl, geranyl, and prenyl groups were synthesized. The obtained compounds were characterized by NMR, HRMS, UV-Vis, IR, and MS. The theoretical analysis was carried out in all the compounds using density functional theory (DFT) with the B3LYP, PBE0, and M06-2X functionals in combination with the 6-311G(d,p) Pople-type basis set. The excited state properties were calculated by time dependent density functional theory (TD-DFT) using the same methodology applied for the ground state properties. The calculated vertical absorption wavelengths (λmax) in gas phase and in ethanol as a solvent are consistent with the experimental ones, being the TD-DFT:B3LYP/6-311G(d,p) and PCM-TD-DFT:PBE0/6-311G(d,p) the best methodologies for these calculations with good approximation to the experimental values. The calculated reorganization energies indicated that, the four chalcone derivatives present an electron transfer character due to the smaller registered values. From these parameters it is proposed that these show an n-type semiconductor character. The localization of the frontier orbitals (HOMO and LUMO) shows that only the compound containing a hydroxyl group on the A-ring displays a marked delocalization favoring the charge-transfer process in this system. The HOMO-LUMO gap energies indicate that the inclusion of different donor groups in the rings does not improve the obtained values for this property. Graphical Abstract Relationship between spectroscopic and geometrical properties of chalcones were carried out using quantum-chemical calculations and compared with experimental values.
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Chalconas/química , Elétrons , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos , Espectrofotometria Ultravioleta/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodosRESUMO
BACKGROUND: Primary immunodeficiencies (PID) represent a heterogeneous group of genetic disorders characterised by poor or absent function in one or more components of the immune system. Humoral or antibody immunodeficiencies are the most common form of PID, of which common variable immunodeficiency (CVID) is the most frequent symptomatic form. CVID is usually characterised by hypogammaglobulinaemia with poor antibody specificity, and an increased susceptibility to infections, autoimmunity and lymphoproliferation. Fewer than 10% of CVID patients have a known monogenic basis. Several chromosomal abnormalities (chromosome 18q-syndrome, monosomy 22, trisomy 8 and trisomy 21) are currently identified as causes of hypogammaglobulinaemia, and can manifest with recurrent infections and mimic CVID. METHODS: Review of clinical charts and laboratory results of paediatric patients followed in the outpatient clinic of PID with a diagnosis of genetic disease and humoral immunodeficiency. RESULTS: Three patients with different genetic diseases (19p13.3 deletion, a ring 18 chromosome and Kabuki syndrome), were identified. During follow-up, they developed signs and symptoms suggestive of humoral deficiency mimicking CVID, despite which immunoglobulin levels were quantified with considerable delay with respect to symptoms onset, and specific management was subsequently delayed. CONCLUSIONS: Patients with genetic abnormalities and recurrent infections should be evaluated for hypogammaglobulinaemia. An early diagnosis of humoral deficiency can allow treatment optimisation to prevent complications and sequelae.
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Anormalidades Múltiplas/imunologia , Deleção Cromossômica , Cromossomos Humanos Par 19/genética , Face/anormalidades , Doenças Hematológicas/imunologia , Imunidade Humoral/genética , Doenças Vestibulares/imunologia , Adolescente , Agamaglobulinemia/diagnóstico , Agamaglobulinemia/genética , Autoimunidade/genética , Criança , Cromossomos Humanos Par 18/imunologia , Cromossomos Humanos Par 19/imunologia , Imunodeficiência de Variável Comum/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Imunoglobulinas Intravenosas , Masculino , Cromossomos em Anel , EspanhaRESUMO
INTRODUCTION: Hypersensitivity reactions to non-steroidal anti-inflammatory drugs (NSAIDs) are the most common reactions to drugs. The prevalence varies from 0.6 to 5.7% in general population, but there are no data available in children. The aim of this study is to determine the frequency of patients diagnosed with hypersensitivity to NSAIDs, and describe their clinical characteristics, type of hypersensitivity, and tolerance to alternative drugs. METHODS: Retrospective study was conducted on children with suspected hypersensitivity to NSAIDs from January 2012 to December 2013. The diagnosis was confirmed by oral drug provocation test (DPT) to the drug involved in the group with a history of one episode, while in the group with a history of more than one episode with the same drug the diagnosis was based on clinical data. Subsequently, a DPT with acetylsalicylic acid (ASA) was done in order to classify hypersensitivity into selective or multiple. In those cases with a positive result, a DPT was performed with alternative drugs. RESULTS: Out of a total of 93 children studied, 26 were diagnosed with hypersensitivity to NSAIDs: 7 confirmed by oral DPT, and 19 based on clinical data. Multiple hypersensitivity was diagnosed in 50% of patients. Ibuprofen was involved in all reactions. The most common clinical manifestation was angioedema (44%). Acetaminophen was the best tolerated alternative drug. CONCLUSIONS: More than one quarter (28%) of the population studied was diagnosed with hypersensitivity to NSAIDs, and 50% had multiple hypersensitivity. Acetaminophen is a safe alternative in children with hypersensitivity to NSAIDs. Meloxicam may be an alternative in cases that do not tolerate acetaminophen.
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Anti-Inflamatórios não Esteroides/efeitos adversos , Hipersensibilidade a Drogas/diagnóstico , Ibuprofeno/efeitos adversos , Acetaminofen , Substituição de Medicamentos , Humanos , Estudos RetrospectivosRESUMO
The Ebola virus is spreading throughout West Africa and is causing thousands of deaths. In order to quantify the effectiveness of different strategies for controlling the spread, we develop a mathematical model in which the propagation of the Ebola virus through Liberia is caused by travel between counties. For the initial months in which the Ebola virus spreads, we find that the arrival times of the disease into the counties predicted by our model are compatible with World Health Organization data, but we also find that reducing mobility is insufficient to contain the epidemic because it delays the arrival of Ebola virus in each county by only a few weeks. We study the effect of a strategy in which safe burials are increased and effective hospitalisation instituted under two scenarios: (i) one implemented in mid-July 2014 and (ii) one in mid-August--which was the actual time that strong interventions began in Liberia. We find that if scenario (i) had been pursued the lifetime of the epidemic would have been three months shorter and the total number of infected individuals 80% less than in scenario (ii). Our projection under scenario (ii) is that the spreading will stop by mid-spring 2015.
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Ebolavirus , Extinção Biológica , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/prevenção & controle , Modelos Teóricos , Algoritmos , Doença pelo Vírus Ebola/transmissão , Humanos , Libéria/epidemiologia , Dinâmica PopulacionalRESUMO
Plant cells outstand for their ability to generate biomass from inorganic sources, this phenomenon takes place within the chloroplasts. The enzymatic machinery and developmental processes of chloroplasts have been subject of research for several decades, and this has resulted in the identification of a plethora of proteins that are essential for their development and function. Mutant lines for the genes that code for those proteins, often display pigment-accumulation defects (e.g., albino phenotypes). Here, we present a comparative proteomic analysis of four chloroplast-biogenesis affected mutants (cla1-1, clb2, clb5, clb19) aiming to identify novel proteins involved in the regulation of chloroplast development in Arabidopsis thaliana. We performed 2D-PAGE separation of the protein samples. These samples were then analyzed by computational processing of gel images in order to select protein spots with abundance shifts of at least twofold, statistically significant according to Student's t-test (P<0.01). These spots were subjected to MALDI-TOF mass-spectrometry for protein identification. This process resulted in the discovery of three novel proteins potentially involved in the development of A. thaliana chloroplasts, as their associated mutant lines segregate pigment-deficient plants with abnormal chloroplasts, and altered mRNA accumulation of chloroplast-development marker genes. BIOLOGICAL SIGNIFICANCE: This report highlights the potential of using a comparative proteomics strategy for the study of biological processes. Particularly, we compared the proteomes of wild-type seedlings and four mutant lines of A. thaliana affected in chloroplast biogenesis. From this proteomic analysis it was possible to detect common mechanisms in the mutants to respond to stress and cope with heterotrophy. Notably, it was possible to identify three novel proteins potentially involved in the development or functioning of chloroplasts, also it was demonstrated that plants annotated to carry T-DNA insertions in the cognate genes display pigment-deficient phenotypes, aberrant and underdeveloped chloroplasts, as well as altered mRNA accumulation of chloroplast biogenesis marker genes.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Cloroplastos/metabolismo , Mutação , Proteômica , Arabidopsis/genética , Cloroplastos/patologia , Análise por Conglomerados , DNA Bacteriano/genética , Eletroforese em Gel Bidimensional , Perfilação da Expressão Gênica , Heterozigoto , Pigmentação , Proteoma , RNA Mensageiro/metabolismo , Plântula/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
The Gamow-Teller strength in the ß(+) direction to (46)Sc was extracted via the (46)Ti(t,(3)He + γ) reaction at 115 MeV/u. The γ-ray coincidences served to precisely measure the very weak Gamow-Teller transition to a final state at 991 keV. Although this transition is weak, it is crucial for accurately estimating electron-capture rates in astrophysical scenarios with relatively low stellar densities and temperatures, such as presupernova stellar evolution. Shell-model calculations with different effective interactions in the pf shell-model space do not reproduce the experimental Gamow-Teller strengths, which is likely due to sd-shell admixtures. Calculations in the quasiparticle random phase approximation that are often used in astrophysical simulations also fail to reproduce the experimental Gamow-Teller strength distribution, leading to strongly overestimated electron-capture rates. Because reliable theoretical predictions of Gamow-Teller strengths are important for providing astrophysical electron-capture reaction rates for a broad set of nuclei in the lower pf shell, we conclude that further theoretical improvements are required to match astrophysical needs.
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Mitogen-activated protein kinase (MAPKs) cascades are signal transduction modules highly conserved in all eukaryotes regulating various aspects of plant biology, including stress responses and developmental programmes. In this study, we characterized the role of MAPK 6 (MPK6) in Arabidopsis embryo development and in post-embryonic root system architecture. We found that the mpk6 mutation caused altered embryo development giving rise to three seed phenotypes that, post-germination, correlated with alterations in root architecture. In the smaller seed class, mutant seedlings failed to develop the primary root, possibly as a result of an earlier defect in the division of the hypophysis cell during embryo development, but they had the capacity to develop adventitious roots to complete their life cycle. In the larger class, the MPK6 loss of function did not cause any evident alteration in seed morphology, but the embryo and the mature seed were bigger than the wild type. Seedlings developed from these bigger seeds were characterized by a primary root longer than that of the wild type, accompanied by significantly increased lateral root initiation and more and longer root hairs. Apparently, the increment in primary root growth resulted from an enhanced cell production and cell elongation. Our data demonstrated that MPK6 plays an important role during embryo development and acts as a repressor of primary and lateral root development.
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Proteínas de Arabidopsis/genética , Arabidopsis/enzimologia , Regulação da Expressão Gênica de Plantas , Sistema de Sinalização das MAP Quinases , Proteínas Quinases Ativadas por Mitógeno/genética , Alelos , Arabidopsis/embriologia , Arabidopsis/genética , Arabidopsis/fisiologia , Proteínas de Arabidopsis/metabolismo , Divisão Celular , Tamanho Celular , Regulação da Expressão Gênica no Desenvolvimento , Germinação , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutação , Fenótipo , Raízes de Plantas/embriologia , Raízes de Plantas/enzimologia , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Plantas Geneticamente Modificadas , Plântula/embriologia , Plântula/enzimologia , Plântula/genética , Plântula/fisiologia , Sementes/embriologia , Sementes/enzimologia , Sementes/genética , Sementes/fisiologiaRESUMO
This data article contains data related to the research article titled Proteomic analysis of chloroplast biogenesis (clb) mutants uncovers novel proteins potentially involved in the development of Arabidopsis thaliana chloroplasts (de Luna-Valdez et al., 2014) [1]. This research article describes the 2-D PAGE-based proteomic analysis of wild-type and four mutant lines (cla1-1, clb2, clb5 and clb19) affected in the development of Arabidopsis thaliana chloroplasts. The report concludes with the discovery of three proteins potentially involved in chloroplast biogenesis. The information presented here represent the tables and figures that detail the processing of the raw data obtained from the image analysis of the 2-D PAGE gels.