RESUMO
Homeobox domain (HD) proteins present a crucial involvement in morphological differentiation and other functions in eukaryotes. Most HD genes encode transcription factors (TFs) that orchestrate a regulatory role in cellular and developmental decisions. In fungi, multiple studies have increased our understanding of these important HD regulators in recent years. These reports have revealed their role in fungal development, both sexual and asexual, as well as their importance in governing other biological processes in these organisms, including secondary metabolism, pathogenicity, and sensitivity to environmental stresses. Here, we provide a comprehensive review of the current knowledge on the regulatory roles of HD-TFs in fungi, with a special focus on Aspergillus species.
Assuntos
Genes Homeobox , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas de Homeodomínio/genética , Aspergillus/genética , Regulação Fúngica da Expressão Gênica , Esporos FúngicosRESUMO
Dripping, jetting and tip streaming have been studied up to a certain point separately by both fluid mechanics and microfluidics communities, the former focusing on fundamental aspects while the latter on applications. Here, we intend to review this field from a global perspective by considering and linking the two sides of the problem. First, we present the theoretical model used to study interfacial flows arising in droplet-based microfluidics, paying attention to three elements commonly present in applications: viscoelasticity, electric fields and surfactants. We review both classical and current results of the stability of jets affected by these elements. Mechanisms leading to the breakup of jets to produce drops are reviewed as well, including some recent advances in this field. We also consider the relatively scarce theoretical studies on the emergence and stability of tip streaming in open systems. Second, we focus on axisymmetric microfluidic configurations which can operate on the dripping and jetting modes either in a direct (standard) way or via tip streaming. We present the dimensionless parameters characterizing these configurations, the scaling laws which allow predicting the size of the resulting droplets and bubbles, as well as those delimiting the parameter windows where tip streaming can be found. Special attention is paid to electrospray and flow focusing, two of the techniques more frequently used in continuous drop production microfluidics. We aim to connect experimental observations described in this section of topics with fundamental and general aspects described in the first part of the review. This work closes with some prospects at both fundamental and practical levels.
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BACKGROUND: Using a double-blinded randomized crossover design, this study aimed to evaluate acute postoperative pain management, swelling and trismus in 46 volunteers undergoing extractions of the two lower third molars, in similar positions, at two different appointments who consumed a tablet of either NE (naproxen 500 mg + esomepraz ole 20 mg) or only naproxen (500 mg) every 12 hours for 4 days. MATERIAL AND METHODS: Parameters were analyzed: self-reported pain intensity using a visual analog scale (VAS) pre- and postoperative mouth opening; incidence, type and severity of adverse reactions; total quantity consumed of rescue medication; and pre- and postoperative swelling. RESULTS: Female volunteers reported significantly more postoperative pain at 1, 1.5, 2, 3 and 4hrs after surgery while also taking their first rescue medication at a time significantly earlier when consuming NE when compared to naproxen (3.7hrs and 6.7hrs). Conversely, no differences were found between each drug group in males. CONCLUSIONS: In conclusion, throughout the entire study, pain was mild after using either drug in both men and women with pain scores on average well below 40mm (VAS), although in women naproxen improved acute postoperative pain management when compared to NE.
Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Esomeprazol/uso terapêutico , Inflamação/tratamento farmacológico , Dente Serotino/cirurgia , Naproxeno/uso terapêutico , Manejo da Dor , Dor Pós-Operatória/tratamento farmacológico , Inibidores da Bomba de Prótons/uso terapêutico , Extração Dentária , Adolescente , Adulto , Estudos Cross-Over , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Masculino , Resultado do Tratamento , Adulto JovemRESUMO
The global regulatory veA gene governs development and secondary metabolism in numerous fungal species, including Aspergillus flavus. This is especially relevant since A. flavus infects crops of agricultural importance worldwide, contaminating them with potent mycotoxins. The most well-known are aflatoxins, which are cytotoxic and carcinogenic polyketide compounds. The production of aflatoxins and the expression of genes implicated in the production of these mycotoxins are veA dependent. The genes responsible for the synthesis of aflatoxins are clustered, a signature common for genes involved in fungal secondary metabolism. Studies of the A. flavus genome revealed many gene clusters possibly connected to the synthesis of secondary metabolites. Many of these metabolites are still unknown, or the association between a known metabolite and a particular gene cluster has not yet been established. In the present transcriptome study, we show that veA is necessary for the expression of a large number of genes. Twenty-eight out of the predicted 56 secondary metabolite gene clusters include at least one gene that is differentially expressed depending on presence or absence of veA. One of the clusters under the influence of veA is cluster 39. The absence of veA results in a downregulation of the five genes found within this cluster. Interestingly, our results indicate that the cluster is expressed mainly in sclerotia. Chemical analysis of sclerotial extracts revealed that cluster 39 is responsible for the production of aflavarin.
Assuntos
Aflatoxinas/genética , Aspergillus flavus/genética , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica/genética , Genes Reguladores/genética , Família Multigênica/genética , Metabolismo Secundário/genética , Fatores de Transcrição/genética , Aflatoxinas/biossíntese , Aspergillus flavus/patogenicidade , Perfilação da Expressão Gênica , Transcriptoma/genéticaRESUMO
Early detection of invasive aspergillosis is absolutely required for efficient therapy of this fungal infection. The identification of fungal volatiles in patient breath can be an alternative for the detection of Aspergillus fumigatus that still remains problematic. In this work, we investigated the production of volatile organic compounds (VOCs) by A. fumigatus in vitro, and we show that volatile production depends on the nutritional environment. A. fumigatus produces a multiplicity of VOCs, predominantly terpenes and related compounds. The production of sesquiterpenoid compounds was found to be strongly induced by increased iron concentrations and certain drugs, i.e., pravastatin. Terpenes that were always detectable in large amounts were α-pinene, camphene, and limonene, as well as sesquiterpenes, identified as α-bergamotene and ß-trans-bergamotene. Other substance classes that were found to be present in the volatome, such as 1-octen-3-ol, 3-octanone, and pyrazines, were found only under specific growth conditions. Drugs that interfere with the terpene biosynthesis pathway influenced the composition of the fungal volatome, and most notably, a block of sesquiterpene biosynthesis by the bisphosphonate alendronate fundamentally changed the VOC composition. Using deletion mutants, we also show that a terpene cyclase and a putative kaurene synthase are essential for the synthesis of volatile terpenes by A. fumigatus. The present analysis of in vitro volatile production by A. fumigatus suggests that VOCs may be used in the diagnosis of infections caused by this fungus.
Assuntos
Aspergillus fumigatus/metabolismo , Sesquiterpenos/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Alquil e Aril Transferases/genética , Aspergillus fumigatus/genética , Proteínas Fúngicas/genética , Técnicas de Inativação de Genes , MetabolomaRESUMO
Flavohemoglobins are widely distributed in both prokaryotes and eukaryotes. These proteins are involved in reducing nitric oxide levels. Deletion of the Aspergillus nidulans flavohemoglobin gene fhbA induced sexual development and decreased sterigmatocystin production. Supplementation with a nitric oxide-releasing compound promoted cleistothecial formation and increased nsdD and steA expression, indicating that nitric oxide induces sexual development. This is the first study on the effect of nitric oxide on morphogenesis and secondary metabolism in fungi.
Assuntos
Aspergillus nidulans/metabolismo , Regulação Fúngica da Expressão Gênica , Hemeproteínas/biossíntese , Micotoxinas/biossíntese , Óxido Nítrico/metabolismo , Aspergillus nidulans/genética , Aspergillus nidulans/crescimento & desenvolvimento , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Genes Fúngicos , Hemeproteínas/genética , Morfogênese/genética , Micotoxinas/genética , RNA Mensageiro/análise , Transdução de Sinais , Esterigmatocistina/biossínteseRESUMO
Light is a major environmental stimulus that has a broad effect on organisms, triggering a cellular response that results in an optimal adaptation enhancing fitness and survival. In fungi, light affects growth, and causes diverse morphological changes such as those leading to reproduction. Light can also affect fungal metabolism, including the biosynthesis of natural products. In this study we show that in Aspergillus nidulans the effect of light on the production of the sterigmatocystin (ST) toxin depends on the glucose concentration. In cultures grown with 1% glucose and exposed to light, ST production was lower than when grown in the dark. This lower ST production coincided with an elevated rate of cellular damage with partial loss of nuclear integrity and vacuolated cytoplasm. However, in cultures grown with 2% glucose these effects were reversed and light enhanced ST production. Glucose abundance also affected the light-dependent subcellular localization of the VeA (velvet) protein, a key regulator necessary for normal light-dependent morphogenesis and secondary metabolism in Aspergilli and other fungal genera. The role of other VeA-associated proteins, particularly the blue-light-sensing proteins LreA and LreB (WC-1 and WC-2 orthologs), on conidiation could also be modified by the abundance of glucose. We also show that LreA and LreB, as well as the phytochrome FphA, modulate not only the synthesis of sterigmatocystin, but also the production of the antibiotic penicillin.
Assuntos
Aspergillus nidulans/crescimento & desenvolvimento , Aspergillus nidulans/efeitos da radiação , Glucose/metabolismo , Morfogênese , Esterigmatocistina/biossíntese , Aspergillus nidulans/genética , Aspergillus nidulans/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica/efeitos da radiação , Luz , Morfogênese/efeitos da radiação , Penicilinas/metabolismo , Transporte Proteico/efeitos da radiaçãoRESUMO
We study theoretically the influence of viscoelasticity on the steady cone-jet mode of electrospray for small stress relaxation times. For this purpose, we numerically integrate the leaky-dielectric model together with the Oldroyd-B constitutive relationship and calculate both the base flow and linear eigenmodes characterizing its stability as a function of the governing parameters. We describe the effect of the polymeric stresses on both the cone-jet mode and the minimum flow rate stability limit. There are considerable differences between the Newtonian and viscoelastic electrospray realizations even for relatively small stress relaxation times due to the intense extensional deformation suffered by the fluid particles in the cone-jet transition region The axial polymeric stress shrinks the liquid meniscus and stabilizes it by pushing the fluid particle in the cone-to-jet transition region.
RESUMO
We introduce a way to stabilize steady micro/nanoliquid jets issuing from Taylor cones together with coflowing gas streams. We study the dripping-jetting transition of this configuration theoretically through a global stability analysis as a function of the governing parameters involved. A balance between the local radial acceleration to the surface tension gradient, the mass conservation, and the energy balance equations enable us to derive two coupled scaling laws that predict both the minimum jet diameter and its maximum velocity. The theoretical prediction provides a single curve that describes not only the numerical computations but also experimental data from the literature for cone jets assisted with gas coflow. Additionally, we performed a set of experiments to verify what parameters influence the jet length. We adopt a very recent model for capillary jet length to our configuration by combining electrohydrodynamic effects with the gas flow through an equivalent liquid pressure. Due to diameters below 1 µm and high speeds attainable in excess of 100 m/s, this concept has the potential to be utilized for structural biology analyses with x-ray free-electron lasers at megahertz repetition rates as well as other applications.
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In the present work, two methods for the preparation of lidocaine-loaded PLGA microparticles are compared. The differences between the polymeric particles obtained by solvent evaporation (SEVM) or flow focusing (FF) were studied by means of scanning electron microscopy and surface thermodynamics determinations. A detailed investigation of the capabilities of the polymer particles to load this drug is described. The physical state of the drug in the polymeric particles and the existence of interactions between both entities were studied by differential scanning calorimetry. The main factors determining the lidocaine incorporation and the release kinetics were the synthesis procedure followed, the amount of drug dissolved in the organic phase during the synthesis routine, the type of polymer (molecular weight and end chemical groups) and the size and the hydrophobic/hydrophilic properties of the particles. The FF technology allowed higher drug incorporations and slower release kinetics. The release studies showed a biphasic profile probably due to diffusion-cum-degradation mediated processes.
Assuntos
Anestésicos Locais/administração & dosagem , Anestésicos Locais/síntese química , Lidocaína/administração & dosagem , Lidocaína/síntese química , Algoritmos , Varredura Diferencial de Calorimetria , Química Farmacêutica , Composição de Medicamentos , Ácido Láctico , Microscopia Eletrônica de Varredura , Nanopartículas , Tamanho da Partícula , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Solubilidade , TermodinâmicaRESUMO
In this paper, linear hydrodynamic stability analysis is used to study the response of a capillary jet and a coflowing fluid to both axisymmetric and nonaxisymmetric perturbations. The temporal analysis revealed that nonaxisymmetric perturbations were damped (or overdamped) within the region of parameter space explored, which involved equal velocities for the jet and focusing fluid. It is explained how an extension to a spatiotemporal analysis implies that those perturbations can yield no transition from convective (jetting) to absolute (whipping) instability for that parameter region. This result provides a theoretical explanation for the absence of that kind of transition in most experimental results in the literature.
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Recent experimental studies on the instability of capillary jets have revealed the suitability of a linear spatiotemporal instability analysis to ascertain the parametrical conditions for specific flow regimes such as steady jetting or dripping. In this work, an extensive analytical, numerical, and experimental description of confined capillary jets is provided, leading to an integrated picture both in terms of data and interpretation. We propose an extended, accurate analytic model in the low Reynolds number limit, and introduce a numerical scheme to predict the system response when the liquid inertia is not negligible. Theoretical predictions show remarkable accuracy when compared with the extensive experimental mapping.
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We compared the clinical efficacy of orally administered valdecoxib and piroxicam for the prevention of pain, trismus and swelling after removal of horizontally and totally intrabony impacted lower third molars. Twenty-five patients were scheduled to undergo removal of symmetrically positioned lower third molars in two separate appointments. Valdecoxib (40 mg) or piroxicam (20 mg) was administered in a double-blind, randomized and crossed manner for 4 days after the surgical procedures. Objective and subjective parameters were recorded for comparison of postoperative courses. Both agents were effective for postoperative pain relief (N = 19). There was a similar mouth opening at suture removal compared with the preoperative values (86.14 +/- 4.36 and 93.12 +/- 3.70% of the initial measure for valdecoxib and piroxicam, respectively; ANOVA). There was no significant difference regarding the total amount of rescue medication taken by the patients treated with valdecoxib or piroxicam (173.08 +/- 91.21 and 461.54 +/- 199.85 mg, respectively; Wilcoxon test). There were no significant differences concerning the swelling observed on the second postoperative day compared to baseline measures (6.15 +/- 1.84 and 8.46 +/- 2.04 mm for valdecoxib and piroxicam, respectively; ANOVA) or on the seventh postoperative day (1.69 +/- 1.61 and 2.23 +/- 2.09 mm for valdecoxib and piroxicam, respectively; ANOVA). The cyclooxygenase-2 selective inhibitor valdecoxib is as effective as the non-selective cyclooxygenase inhibitor piroxicam for pain, trismus and swelling control after removal of horizontally and totally intrabony impacted lower third molars.
Assuntos
Inibidores de Ciclo-Oxigenase/uso terapêutico , Edema/tratamento farmacológico , Isoxazóis/uso terapêutico , Dente Serotino/cirurgia , Dor Pós-Operatória/tratamento farmacológico , Piroxicam/uso terapêutico , Sulfonamidas/uso terapêutico , Trismo/tratamento farmacológico , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino , Extração Dentária , Resultado do TratamentoRESUMO
Fifty patients were scheduled to undergo removal of symmetrically positioned lower third molars in two separate appointments. Meloxicam 7.5 or 15 mg was once daily administered in a double-blind, randomized and crossover manner after the surgery for 4 days. Objective and subjective parameters were recorded for comparison of postoperative courses. Patients treated with 7.5mg meloxicam who underwent osteotomy reported higher pain scores at 1.5, 3, 4, 10, 12 and 16 h (P<0.05) and ingested a greater amount of rescue analgesic medication (P<0.05) than those who did not require osteotomy. A higher percentage of patients who underwent osteotomy medicated with 7.5mg meloxicam needed rescue medication as compared to those who did not require osteotomy (P<0.05). There was a similar mouth opening at suture removal compared with preoperative values for both doses (P>0.05). There were no significant differences concerning swelling observed on the 2nd or 7th postoperative days in comparison with baseline (P>0.05) between the two doses. Pain, trismus and swelling after lower third molar removal not requiring osteotomy can be successfully controlled by a dose regimen of 7.5mg meloxicam once daily. For more aggressive extractions 15 mg meloxicam is advisable.
Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Dente Serotino/cirurgia , Dor Pós-Operatória/prevenção & controle , Tiazinas/administração & dosagem , Tiazóis/administração & dosagem , Extração Dentária , Administração Oral , Adulto , Análise de Variância , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Edema/prevenção & controle , Feminino , Humanos , Masculino , Meloxicam , Osteotomia , Amplitude de Movimento Articular , Estatísticas não Paramétricas , Extração Dentária/efeitos adversos , Dente Impactado/cirurgia , Trismo/prevenção & controleRESUMO
Osseous hydatid disease is an infrequent entity that represents 0.5-2.5% of all hydatidoses. The vertebrae are the most commonly affected bones (50%), followed by the pelvis (25%) and the long bones (15-25%). The clinical manifestations appear when there is large scale osseous destruction or complications, which is why the diagnosis is generally made in late stages through imaging techniques and on occasion in an intra-operational form. Treatment in operable cases is by surgical extirpation, which can be associated with medical treatment with albendazol. We present the case of a patient with osseous hydatidosis, localised in the pelvis, with an absence of other affected organs. The only clinical manifestation presented by the patient was an inguinal tumour on the right side. The patient received a clinical intervention facing the suspicion of an inguinal hernia, complicated by the intra-operational discovery of pelvic hydatidosis.
Assuntos
Doenças Ósseas , Equinococose , Echinococcus granulosus , Osso Púbico , Administração Oral , Idoso , Albendazol/administração & dosagem , Albendazol/uso terapêutico , Animais , Anticestoides/administração & dosagem , Anticestoides/uso terapêutico , Doenças Ósseas/diagnóstico , Doenças Ósseas/diagnóstico por imagem , Doenças Ósseas/tratamento farmacológico , Doenças Ósseas/cirurgia , Diagnóstico Diferencial , Equinococose/diagnóstico , Equinococose/diagnóstico por imagem , Equinococose/tratamento farmacológico , Equinococose/cirurgia , Hérnia Inguinal/diagnóstico , Humanos , Masculino , Radiografia Abdominal , Tomografia Computadorizada por Raios XRESUMO
Postoperative pain and inflammation after oral surgery is mostly managed using non-steroidal anti-inflammatory drugs (NSAIDs). However, opioids combined with NSAIDs may improve pain management in patients, especially after traumatic oral surgery. Few studies have compared NSAIDs with and without opioid use after oral and maxillofacial surgery. This randomized, double-blind, cross-over study compared the clinical efficacy of either diclofenac (50mg) and codeine (50mg) or diclofenac alone (50mg) for the management of postoperative pain after invasive third molar surgery. Volunteers (n=46) who were scheduled to undergo the removal of symmetrically positioned lower third molars in two separate appointments were included. They reported significantly less postoperative pain at various time points within 24h after surgery and also consumed significantly less rescue medication (paracetamol (acetaminophen)) throughout the study when they took diclofenac combined with codeine than when they took only diclofenac. In conclusion, oral diclofenac with codeine was more effective for managing postoperative pain than diclofenac without codeine. It was expected that patients taking two pain medications after surgery would generally have less pain than when taking only one of the two medications. The prospective cross-over design of the present work makes this study distinct from many others.
Assuntos
Analgésicos Opioides/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Codeína/uso terapêutico , Diclofenaco/uso terapêutico , Dente Serotino/cirurgia , Dor Pós-Operatória/tratamento farmacológico , Dente Impactado/cirurgia , Administração Oral , Analgésicos Opioides/administração & dosagem , Anti-Inflamatórios não Esteroides/administração & dosagem , Codeína/administração & dosagem , Estudos Cross-Over , Diclofenaco/administração & dosagem , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Masculino , Manejo da Dor , Medição da Dor , Extração Dentária , Resultado do Tratamento , Adulto JovemRESUMO
Fluorescently encoded polymeric microparticles are acquiring great importance in the development of simultaneous multianalyte screening assays. We have developed a very versatile and straightforward method for the production of dye-labeled microparticles with a very reproducible size distribution and freely-chosen and discernible fluorescent properties. Our method combines Flow Focusing technology with a solvent evaporation/extraction procedure in a single step, yielding spherical, non-aggregate and non-porous particles. We have designed a multi-coloured bead array which includes the possibility of modifying the surface properties of the microparticles, which offer excellent properties for covalent attachment of biomolecules such as peptides, oligonucleotides, proteins, etc. We also show the potential of the fluorescently labeled microspheres for the detection of biomolecule (peptides and oligonucelotides) interactions using flow cytometry.
Assuntos
Composição de Medicamentos , Nanopartículas , Fenômenos Químicos , Físico-Química , Citometria de Fluxo , Corantes Fluorescentes , Concentração de Íons de Hidrogênio , Ligantes , Microscopia Confocal , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência , Tamanho da Partícula , Fotodegradação , Polímeros , SolventesRESUMO
We identify and analyze the perfectly regular dripping mode of flow focusing. This mode occurs within narrow intervals of injected flow rates and applied pressure drops and leads to homogeneous-size droplets with diameters similar to or smaller than that of the discharge orifice. The balance between the local acceleration of the fluid particle and the applied pressure drop yields the scaling law for the droplet diameter. This scaling law is validated experimentally with excellent accord.
RESUMO
The disintegration of liquid drops with low electrical conductivity and subject to an electric field is investigated both theoretically and experimentally. This disintegration takes place through the development of a conical cusp that eventually ejects an ultrathin liquid ligament. A first tiny drop is emitted from the end of this ligament. Due to its exceptionally small size and large electric charge per unit volume, that drop has been the object of relevant recent studies. In this paper, universal scaling laws for the diameter and electric charge of the first issued droplet are proposed and validated both numerically and experimentally. Our analysis shows how charge relaxation is the mechanism that differentiates the onset of electrospray, including the first droplet ejection, from the classical steady cone-jet mode. In this way, our study identifies when and where charge relaxation and electrokinetic phenomena come into play in electrospray, a subject of live controversy in the field.