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1.
Chemosphere ; 335: 139121, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37271465

RESUMO

3-Nitro-1,2,4-triazol-5-one (NTO) is an ingredient of new safer-to-handle military insensitive munitions formulations. NTO can be microbially reduced to 3-amino-1,2,4-triazol-5-one (ATO) under anaerobic conditions if an electron donor is available. Conversely, ATO can undergo aerobic biodegradation. Previously, our research group developed an anaerobic enrichment culture that reduces NTO to ATO. A second culture could aerobically mineralize ATO. This study aimed to combine anaerobic/aerobic conditions within a down-flow perlite/soil column for simultaneous NTO reduction and ATO oxidation. Acetate biostimulation was investigated to promote oxygen depletion and create anaerobic micro-niches for NTO reduction, whereas perlite increased soil porosity and oxygen convection, allowing ATO oxidation. Two columns packed with a perlite/soil mixture (70:30, wet wt.%) or 100% perlite were operated aerobically and inoculated with the NTO- and ATO-degrading cultures. Initially, the influent consisted of ∼280 µM ATO, and after 30 days, the feeding was switched to ∼260 µM NTO and ∼250 µM acetate. By progressively increasing acetate from 250 to 4000 µM, the NTO removal gradually improved in both columns. The perlite/soil column reached a 100% NTO removal after 4000 µM acetate was supplemented. Additionally, there was no ATO accumulation, and inorganic nitrogen was produced, indicating ATO mineralization. Although NH4+ was produced following ATO oxidation, most nitrogen was recovered as NO3- likely via nitrification reactions. Microbial community analysis revealed that phylotypes hosted in the enrichment cultures specialized in NTO reduction (e.g., Geobacter) and ATO oxidation (e.g., Hydrogenophaga, Ramlibacter, Terrimonas, and Pseudomonas) were established in the columns. Besides, the predominant genera (Azohydromonas, Zoogloea, and Azospirillum) are linked to nitrogen cycling by performing nitrogen fixation, NO3- reduction, and nitroaromatics degradation. This study applied a bulking agent (perlite) and acetate biostimulation to achieve simultaneous NTO reduction and ATO oxidation in a single column. Such a strategy can assist with real-world applications of NTO and ATO biodegradation mechanisms.


Assuntos
Nitrocompostos , Solo , Biodegradação Ambiental , Nitrocompostos/metabolismo , Nitrogênio/metabolismo
2.
Proc Natl Acad Sci U S A ; 120(15): e2220891120, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-37018203

RESUMO

Hypoxia is a prognostic biomarker of rapidly growing cancers, where the extent of hypoxia is an indication of tumor progression and prognosis; therefore, hypoxia is also used for staging while performing chemo- and radiotherapeutics for cancer. Contrast-enhanced MRI using EuII-based contrast agents is a noninvasive method that can be used to map hypoxic tumors, but quantification of hypoxia using these agents is challenging due to the dependence of signal on the concentration of both oxygen and EuII. Here, we report a ratiometric method to eliminate concentration dependence of contrast enhancement of hypoxia using fluorinated EuII/III-containing probes. We studied three different EuII/III couples of complexes containing 4, 12, or 24 fluorine atoms to balance fluorine signal-to-noise ratio with aqueous solubility. The ratio between the longitudinal relaxation time (T1) and 19F signal of solutions containing different ratios of EuII- and EuIII-containing complexes was plotted against the percentage of EuII-containing complexes in solution. We denote the slope of the resulting curves as hypoxia indices because they can be used to quantify signal enhancement from Eu, that is related to oxygen concentration, without knowledge of the absolute concentration of Eu. This mapping of hypoxia was demonstrated in vivo in an orthotopic syngeneic tumor model. Our studies significantly contribute toward improving the ability to radiographically map and quantify hypoxia in real time, which is critical to the study of cancer and a wide range of diseases.


Assuntos
Flúor , Neoplasias , Humanos , Imageamento por Ressonância Magnética/métodos , Hipóxia , Oxigênio
3.
Adv Healthc Mater ; 12(19): e2203209, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36906514

RESUMO

Radiographic mapping of hypoxia is needed to study a wide range of diseases. Complexes of Eu(II) are a promising class of molecules to fit this need, but they are generally limited by their rapid oxidation rates in vivo. Here, a perfluorocarbon-nanoemulsion perfused with N2 , forms an interface with aqueous layers to hinder oxidation of a new perfluorocarbon-soluble complex of Eu(II). Conversion of the perfluorocarbon solution of Eu(II) into nanoemulsions results in observable differences between reduced and oxidized forms by magnetic resonance imaging both in vitro and in vivo. Oxidation in vivo occurrs over a period of ≈30 min compared to <5 min for a comparable Eu(II)-containing complex without nanoparticle interfaces. These results represent a critical step toward delivery of Eu(II)-containing complexes in vivo for the study of hypoxia.


Assuntos
Európio , Fluorocarbonos , Humanos , Meios de Contraste , Oxigênio , Imageamento por Ressonância Magnética/métodos , Hipóxia
4.
Water Res ; 229: 119496, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36535085

RESUMO

Nitroguanidine (NQ) is a constituent of gas generators for automobile airbags, smokeless pyrotechnics, insecticides, propellants, and new insensitive munitions formulations applied by the military. During its manufacture and use, NQ can easily spread in soils, ground, and surface waters due to its high aqueous solubility. Very little is known about the microbial biotransformation of NQ. This study aimed to elucidate important mechanisms operating during NQ anaerobic biotransformation. To achieve this goal, we developed an anaerobic enrichment culture able to reduce NQ to nitrosoguanidine (NsoQ), which was further abiotically transformed to cyanamide. Effective electron donors for NQ biotransformation were lactate and, to a lesser extent, pyruvate. The results demonstrate that the enrichment process selected a sulfate-reducing culture that utilized lactate as its electron donor and sulfate as its electron acceptor while competing with NQ as an electron sink. A unique property of the culture was its requirement for exogenous nitrogen (e.g., from yeast extract or NH4Cl) for NQ biotransformation since NQ itself did not serve as a nitrogen source. The main phylogenetic groups associated with the NQ-reducing culture were sulfate-reducing and fermentative bacteria, namely Cupidesulfovibrio oxamicus (63.1% relative abundance), Dendrosporobacter spp. (12.0%), and Raoultibacter massiliens (10.9%). The molecular ecology results corresponded to measurable physiological properties of the most abundant members. The results establish the conditions for NQ anaerobic biotransformation and the microbial community associated with the process, improving our present comprehension of NQ environmental fate and assisting the development of NQ remediation strategies.


Assuntos
Nitrogênio , Triazóis , Anaerobiose , Filogenia , Biotransformação
5.
Viruses ; 14(9)2022 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-36146768

RESUMO

Of individuals who develop West Nile neuroinvasive disease (WNND), ~10% will die and >40% will develop long-term complications. Current treatment recommendations solely focus on supportive care; therefore, we urgently need to identify novel and effective therapeutic options. We observed a correlation between substance P (SP), a key player in neuroinflammation, and its receptor Neurokinin-1 (NK1R). Our study in a wild-type BL6 mouse model found that SP is upregulated in the brain during infection, which correlated with neuroinvasion and damage to the blood−brain barrier. Blocking the SP/NK1R interaction beginning at disease onset modestly improved survival and prolonged time to death in a small pilot study. Although SP is significantly increased in the brain of untreated WNND mice when compared to mock-infected animals, levels of WNV are unchanged, indicating that SP likely does not play a role in viral replication but may mediate the immune response to infection. Additional studies are necessary to define if SP plays a mechanistic role or if it represents other mechanistic pathways.


Assuntos
Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Encéfalo , Camundongos , Projetos Piloto , Substância P , Vírus do Nilo Ocidental/fisiologia
6.
Biosensors (Basel) ; 12(8)2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-36005011

RESUMO

Anesthesia is often used in preclinical imaging studies that incorporate mouse or rat models. However, multiple reports indicate that anesthesia has significant physiological impacts. Thus, there has been great interest in performing imaging studies in awake, unanesthetized animals to obtain accurate results without the confounding physiological effects of anesthesia. Here, we describe a newly designed mouse holder that is interfaceable with existing MRI systems and enables awake in vivo mouse imaging. This holder significantly reduces head movement of the awake animal compared to previously designed holders and allows for the acquisition of improved anatomical images. In addition to applications in anatomical T2-weighted magnetic resonance imaging (MRI), we also describe applications in acquiring 31P spectra, manganese-enhanced magnetic resonance imaging (MEMRI) transport rates and resting-state functional magnetic resonance imaging (rs-fMRI) in awake animals and describe a successful conditioning paradigm for awake imaging. These data demonstrate significant differences in 31P spectra, MEMRI transport rates, and rs-fMRI connectivity between anesthetized and awake animals, emphasizing the importance of performing functional studies in unanesthetized animals. Furthermore, these studies demonstrate that the mouse holder presented here is easy to construct and use, compatible with standard Bruker systems for mouse imaging, and provides rigorous results in awake mice.


Assuntos
Manganês , Vigília , Animais , Encéfalo , Imageamento por Ressonância Magnética/métodos , Manganês/farmacologia , Camundongos , Ratos , Análise Espectral
7.
Environ Pollut ; 309: 119788, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35843454

RESUMO

Nitroguanidine (NQ) is an emerging contaminant being used by the military as a constituent of new insensitive munitions. NQ is also used in rocket propellants, smokeless pyrotechnics, and vehicle restraint systems. Its uncontrolled transformation in the environment can generate toxic and potentially mutagenic products, posing hazards that need to be remediated. NQ transformation has only been investigated to a limited extent. Thus, it is crucial to expand the narrow spectrum of NQ remediation strategies and understand its transformation pathways and end products. Iron-based reactive minerals should be investigated for NQ treatment because they are successfully used in existing technologies, such as permeable reactive barriers, for treating a wide range of organic pollutants. This study tested the ability of micron-sized zero-valent iron (m-ZVI), mackinawite, and commercial FeS, to transform NQ under anoxic conditions. NQ transformation followed pseudo-first-order kinetics. The reaction rate constants decreased as follows: commercial FeS > mackinawite > m-ZVI. For the assessed minerals, the NQ transformation started with the reduction of the nitro group forming nitrosoguanidine (NsoQ). Then, aminoguanidine (AQ) was accumulated during the reaction of NQ with m-ZVI, accounting for 86% of the nitrogen mass recovery. When NQ was reacted with commercial FeS, 45% and 20% of nitrogen were recovered as AQ and guanidine, respectively, after 24 h. Nonetheless, NsoQ persisted, contributing to the N-balance. When mackinawite was present, NsoQ disappeared, but AQ was not detected, and guanidine accounted for 11% of the nitrogen recovery. AQ was ultimately transformed into cyanamide, whose dimerization triggered the formation of cyanoguanidine. Alternatively, NsoQ was transformed into guanidine, which reacted with cyanamide to form biguanide. This is the first report systematically investigating the NQ transformation by different iron-based reactive minerals. The evidence indicates that these minerals are attractive alternatives for developing NQ remediation strategies.


Assuntos
Ferro , Poluentes Químicos da Água , Cianamida , Guanidinas , Minerais , Nitrogênio
8.
Cardiooncology ; 7(1): 23, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34134789

RESUMO

BACKGROUND: Cancer therapy-related cardiac dysfunction may occur in pediatric cancer survivors. Identification of early markers of myocardial damage secondary to anthracycline exposure is crucial to develop strategies that may ameliorate this complication. OBJECTIVES: The purpose of this study was to identify early myocardial changes induced by doxorubicin with and without cardioprotection using dexrazoxane detected by serial cardiac magnetic resonance imaging (CMR) in a pre-clinical mouse model. METHODS: Serial CMR examinations were performed in 90 mice distributed in 3 groups: 45 received doxorubicin (DOX group), 30 mice received doxorubicin with dexrazoxane (DOX/DEX group) and 15 mice received saline injections (control group). We obtained the following CMR parameters in all mice: T2, extracellular volume quantification (ECV), myocardial deformation, and functional quantification. RESULTS: Myocardial edema assessed by T2 time was the earliest parameter demonstrating evidence of myocardial injury, most notable in the DOX group at week 4 and 8 compared with DOX/DEX group. Similarly, global longitudinal strain was abnormal in both the DOX and DOX/DEX groups. However, this change persisted only in the DOX group. The ECV was significantly elevated in the DOX group at the final CMR, while only minimally elevated in the DOX/DEX group. The right and left ejection fraction was decreased, along with the mass to volume ratio in the DOX group. The T2 time, ECV, and deformation correlated with ejection fraction and left ventricular volume. CONCLUSIONS: T2 time and deformation by CMR identifies early myocardial injury from anthracyclines. Dexrazoxne did not prevent the initial edema, but the inflammatory changes were not sustained. CMR may be useful for early detection of cardiac dysfunction. Serial CMR demonstrates dexrazoxane minimizes cardiac dysfunction and aids recovery in a mouse model.

9.
Hortic Res ; 8(1): 73, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33790231

RESUMO

Abiotic stresses have a negative effect on crop production, affecting both vegetative and reproductive development. Ethylene plays a relevant role in plant response to environmental stresses, but the specific contribution of ethylene biosynthesis and signalling components in the salt stress response differs between Arabidopsis and rice, the two most studied model plants. In this paper, we study the effect of three gain-of-function mutations affecting the ethylene receptors CpETR1B, CpETR1A, and CpETR2B of Cucurbita pepo on salt stress response during germination, seedling establishment, and subsequent vegetative growth of plants. The mutations all reduced ethylene sensitivity, but enhanced salt tolerance, during both germination and vegetative growth, demonstrating that the three ethylene receptors play a positive role in salt tolerance. Under salt stress, etr1b, etr1a, and etr2b germinate earlier than WT, and the root and shoot growth rates of both seedlings and plants were less affected in mutant than in WT. The enhanced salt tolerance response of the etr2b plants was associated with a reduced accumulation of Na+ in shoots and leaves, as well as with a higher accumulation of compatible solutes, including proline and total carbohydrates, and antioxidant compounds, such as anthocyanin. Many membrane monovalent cation transporters, including Na+/H+ and K+/H+ exchangers (NHXs), K+ efflux antiporters (KEAs), high-affinity K+ transporters (HKTs), and K+ uptake transporters (KUPs) were also highly upregulated by salt in etr2b in comparison with WT. In aggregate, these data indicate that the enhanced salt tolerance of the mutant is led by the induction of genes that exclude Na+ in photosynthetic organs, while maintaining K+/Na+ homoeostasis and osmotic adjustment. If the salt response of etr mutants occurs via the ethylene signalling pathway, our data show that ethylene is a negative regulator of salt tolerance during germination and vegetative growth. Nevertheless, the higher upregulation of genes involved in Ca2+ signalling (CpCRCK2A and CpCRCK2B) and ABA biosynthesis (CpNCED3A and CpNCED3B) in etr2b leaves under salt stress likely indicates that the function of ethylene receptors in salt stress response in C. pepo can be mediated by Ca2+ and ABA signalling pathways.

10.
Chem Commun (Camb) ; 57(14): 1770-1773, 2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33475101

RESUMO

The complexes described here serve as contrast agents for magnetic resonance imaging thermometry. The complexes differentially enhance contrast between 275 and 325 K. The basis of the temperature response of the fluorinated contrast complex is the modulation of water exchange caused by trifluoromethyl groups that can be chemically controlled.

11.
Front Plant Sci ; 12: 817922, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35140733

RESUMO

A methanesulfonate-generated mutant has been identified in Cucurbita pepo that alters sex determination. The mutation converts female into hermaphrodite flowers and disrupts the growth rate and maturation of petals and carpels, delaying female flower opening, and promoting the growth rate of ovaries and the parthenocarpic development of the fruit. Whole-genome resequencing allowed identification of the causal mutation of the phenotypes as a missense mutation in the coding region of CpACO1A, which encodes for a type I ACO enzyme that shares a high identity with Cucumis sativus CsACO3 and Cucumis melo CmACO1. The so-called aco1a reduced ACO1 activity and ethylene production in the different organs where the gene is expressed, and reduced ethylene sensitivity in flowers. Other sex-determining genes, such as CpACO2B, CpACS11A, and CpACS27A, were differentially expressed in the mutant, indicating that ethylene provided by CpACO1A but also the transcriptional regulation of CpACO1A, CpACO2B, CpACS11A, and CpACS27A are responsible for determining the fate of the floral meristem toward a female flower, promoting the development of carpels and arresting the development of stamens. The positive regulation of ethylene on petal maturation and flower opening can be mediated by inducing the biosynthesis of JA, while its negative control on ovary growth and fruit set could be mediated by its repressive effect on IAA biosynthesis.

12.
Nat Commun ; 11(1): 5099, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-33037202

RESUMO

Mutations in the skeletal muscle Ca2+ release channel, the type 1 ryanodine receptor (RYR1), cause malignant hyperthermia susceptibility (MHS) and a life-threatening sensitivity to heat, which is most severe in children. Mice with an MHS-associated mutation in Ryr1 (Y524S, YS) display lethal muscle contractures in response to heat. Here we show that the heat response in the YS mice is exacerbated by brown fat adaptive thermogenesis. In addition, the YS mice have more brown adipose tissue thermogenic capacity than their littermate controls. Blood lactate levels are elevated in both heat-sensitive MHS patients with RYR1 mutations and YS mice due to Ca2+ driven increases in muscle metabolism. Lactate increases brown adipogenesis in both mouse and human brown preadipocytes. This study suggests that simple lifestyle modifications such as avoiding extreme temperatures and maintaining thermoneutrality could decrease the risk of life-threatening responses to heat and exercise in individuals with RYR1 pathogenic variants.


Assuntos
Hipertermia Maligna/genética , Mutação , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Termogênese/fisiologia , Tecido Adiposo Marrom/metabolismo , Adolescente , Adulto , Animais , Criança , Pré-Escolar , Feminino , Resposta ao Choque Térmico/genética , Resposta ao Choque Térmico/fisiologia , Humanos , Lactente , Lactatos/sangue , Masculino , Hipertermia Maligna/etiologia , Hipertermia Maligna/mortalidade , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Estudos Retrospectivos , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Termogênese/genética , Proteína Desacopladora 1/genética , Adulto Jovem
13.
Front Plant Sci ; 11: 1243, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32973825

RESUMO

The sexual expression of watermelon plants is the result of the distribution and occurrence of male, female, bisexual and hermaphrodite flowers on the main and secondary stems. Plants can be monoecious (producing male and female flowers), andromonoecious (producing male and hermaphrodite flowers), or partially andromonoecious (producing male, female, bisexual, and hermaphrodite flowers) within the same plant. Sex determination of individual floral buds and the distribution of the different flower types on the plant, are both controlled by ethylene. A single missense mutation in the ethylene biosynthesis gene CitACS4, is able to promote the conversion of female into hermaphrodite flowers, and therefore of monoecy (genotype MM) into partial andromonoecy (genotype Mm) or andromonoecy (genotype mm). We phenotyped and genotyped, for the M/m locus, a panel of 207 C. lanatus accessions, including five inbreds and hybrids, and found several accessions that were repeatedly phenotyped as PA (partially andromonoecious) in several locations and different years, despite being MM. A cosegregation analysis between a SNV in CitACS4 and the PA phenotype, demonstrated that the occurrence of bisexual and hermaphrodite flowers in a PA line is not dependent on CitACS4, but conferred by an unlinked recessive gene which we called pa. Two different approaches were performed to map the pa gene in the genome of C. lanatus: bulk segregant analysis sequencing (BSA-seq) and genome wide association analysis studies (GWAS). The BSA-seq study was performed using two contrasting bulks, the monoecious M-bulk and the partially andromonoecious PA-bulk, each one generated by pooling DNA from 20 F2 plants. For GWAS, 122 accessions from USDA gene bank, already re-sequenced by genotyping by sequencing (GBS), were used. The combination of the two approaches indicates that pa maps onto a genomic region expanding across 32.24-36.44 Mb in chromosome 1 of watermelon. Fine mapping narrowed down the pa locus to a 867 Kb genomic region containing 101 genes. A number of candidate genes were selected, not only for their function in ethylene biosynthesis and signalling as well as their role in flower development and sex determination, but also by the impact of the SNPs and indels differentially detected in the two sequenced bulks.

14.
Rev. chil. anest ; 49(1): 141-145, 2020. ilus
Artigo em Espanhol | LILACS | ID: biblio-1510352

RESUMO

Ultrasound regional blockade emerged that blocks the branches of the femoral nerve, obturator and accessory obturator that innervate the anterior hip capsule, the PENG block (group of pericapsular nerves), which by its Recent description does not have enough evidence in medical practice. To verify the analgesic effect of the PENG block in patients with hip fracture and its analgesic permanence during the first 10 hours after the block in patients admitted with a diagnosis of hip fracture, at the General Interzonal Hospital of Acute "Dr Oscar E Alende "From Mar del Plata, Argentina, in the months of May to November 2019. A prospective descriptive observational study was carried out with a total of 53 patients, hospitalized patients with a diagnosis of hip fracture, with standardized intravenous analgesic scheme and who have not yet undergone hip surgery. Pain was evaluated with the EVA scale (visual analog scale) prior to the blockage, and then at 30 min and 10 hours after the blockade, 15 ml of 1% lidocaine and 15 ml of bupivacaine at 0 were used. 25%, convex or linear ultrasound probe according to patient weight and 100 mm needle. In order to reproduce and evaluate the pain, the patients had a 30º flexion of the hip. Prior to the blockade, 66% of the patients had severe pain and 34% moderate pain, none presented mild pain or absence, both at thirty minutes and ten hours after the blockade, no patient presented severe pain and all patients presented analgesia with a decrease in more than three points on the VAS scale, in some cases reaching a decrease of 10 points on that scale. The PENG block is a regional anesthesia technique that provides very good analgesia to patients with hip fractures, therefore, it is an excellent saving strategy for systemic analgesics. Knowing the analgesia provided by the blockade at 30 min and at 10 h, it could be performed both in the preoperative period for the transfer and mobilization of the patient, as well as in the postoperative period, which could save the use of opioids and decrease hospital stay.


INTRODUCCIÓN La fractura de cadera es una emergencia ortopédica común en ancianos asociada a gran morbimortalidad, una adecuada analgesia regional perioperatoria determina un ahorro en el uso de analgésicos sistémicos. Recientemente, en el año 2018, surgió un nuevo bloqueo regional ecoguiado muy prometedor que bloquea las ramas del nervio femoral, obturador y obturador accesorio que inervan la capsula anterior de la cadera, el bloqueo PENG (grupo de nervios pericapsulares), el cual por su reciente descripción no cuenta con la suficiente evidencia en la práctica médica. OBJETIVOS: Comprobar el efecto analgésico del bloqueo PENG en pacientes con fractura de cadera y su permanencia analgésica durante las 10 primeras horas posteriores al bloqueo en los pacientes internados con diagnóstico de fractura de cadera, en el Hospital Interzonal General de Agudos "Dr. Oscar E Alende" de Mar del Plata, Argentina, en los meses de mayo a noviembre del 2019. MATERIALES Y MÉTODOS: Se realizó un estudio observacional descriptivo prospectivo con un total de 53 pacientes, se incluyeron pacientes internados con diagnóstico de fractura de cadera, con esquema analgésico endovenoso estandarizado y que aún no hayan sido sometido a cirugía de cadera. Se evaluó el dolor con la escala EVA (escala análoga visual) previo al bloqueo, y luego a los 30 min y a las 10 Hs de haber realizado el bloqueo, para este se utilizaron 15 ml lidocaína 1% y 15 ml de bupivacaína al 0,25%, sonda ecográfica convexa o lineal según el peso del paciente y aguja 100 mm. Para reproducir y evaluar el dolor se les realizo a los pacientes una flexión de 30º de la cadera. RESULTADOS: Previo al bloqueo el 66% de los pacientes tuvieron dolor severo y 34% dolor moderado, ninguno presentaba dolor leve o ausencia del mismo, tanto a los treinta minutos como a las diez horas posteriores al bloqueo ningún paciente presento dolor severo y todos los pacientes presentaron analgesia con una disminución en más de tres puntos en la escala de EVA, llegando en algunos casos a una disminución de 10 puntos de dicha escala. CONCLUSIONES: El bloqueo PENG es una técnica de anestesia regional que brinda muy buena analgesia a los pacientes con fractura de cadera, por consiguiente, es una excelente estrategia ahorradora de analgésicos sistémicos. Conociendo la analgesia que brinda el bloqueo a los 30 min y a las 10 h de realizado, se podría realizar dicho bloqueo tanto en el preoperatorio para el traslado y movilización del paciente, como en el post-operatorio, lo que podría ahorrar el uso de opioides y disminuir la estancia hospitalaria.


Assuntos
Humanos , Fraturas do Quadril/diagnóstico por imagem , Anestésicos Locais/administração & dosagem , Fatores de Tempo , Medição da Dor , Cuidados Pré-Operatórios , Estudos Prospectivos , Ultrassonografia de Intervenção , Relação Dose-Resposta a Droga , Nervo Femoral/efeitos dos fármacos , Nervo Femoral/diagnóstico por imagem , Anestesia por Condução/métodos , Anestésicos Locais/farmacologia , Nervo Obturador/efeitos dos fármacos , Nervo Obturador/diagnóstico por imagem
16.
Chem Rev ; 119(19): 10856-10915, 2019 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-31469277

RESUMO

Practical challenges in simulating quantum systems on classical computers have been widely recognized in the quantum physics and quantum chemistry communities over the past century. Although many approximation methods have been introduced, the complexity of quantum mechanics remains hard to appease. The advent of quantum computation brings new pathways to navigate this challenging and complex landscape. By manipulating quantum states of matter and taking advantage of their unique features such as superposition and entanglement, quantum computers promise to efficiently deliver accurate results for many important problems in quantum chemistry, such as the electronic structure of molecules. In the past two decades, significant advances have been made in developing algorithms and physical hardware for quantum computing, heralding a revolution in simulation of quantum systems. This Review provides an overview of the algorithms and results that are relevant for quantum chemistry. The intended audience is both quantum chemists who seek to learn more about quantum computing and quantum computing researchers who would like to explore applications in quantum chemistry.


Assuntos
Modelos Químicos , Teoria Quântica , Algoritmos , Metodologias Computacionais , Simulação de Dinâmica Molecular
19.
Contrast Media Mol Imaging ; 2018: 1693513, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30538612

RESUMO

Fluorine-19 (19F) magnetic resonance imaging (MRI) has the potential for a wide range of in vivo applications but is limited by lack of flexibility in exogenous probe formulation. Most 19F MRI probes are composed of perfluorocarbons (PFCs) or perfluoropolyethers (PFPEs) with intrinsic properties which limit formulation options. Hydrophilic organofluorine molecules can provide more flexibility in formulation options. We report herein a hyperfluorinated hydrophilic organoflourine, ET1084, with ∼24 wt. % 19F content. It dissolves in water and aqueous buffers to give solutions with ≥8 M 19F. 19F MRI phantom studies at 9.4T employing a 10-minute multislice multiecho (MSME) scan sequence show a linear increase in signal-to-noise ratio (SNR) with increasing concentrations of the molecule and a detection limit of 5 mM. Preliminary cytotoxicity and genotoxicity assessments suggest it is safe at concentrations of up to 20 mM.


Assuntos
Meios de Contraste/química , Flúor , Fluorocarbonos/química , Imageamento por Ressonância Magnética/métodos , Meios de Contraste/toxicidade , Fluorocarbonos/toxicidade , Interações Hidrofóbicas e Hidrofílicas , Limite de Detecção , Imagens de Fantasmas , Razão Sinal-Ruído , Solubilidade
20.
Front Plant Sci ; 9: 1049, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30123227

RESUMO

The Cucurbita pepo genome comprises 263 Mb and 34,240 gene models organized in 20 different chromosomes. To improve our understanding of gene function we have generated an EMS mutant platform, consisting of 3,751 independent M2 families. The quality of the collection has been evaluated based on phenotyping and whole-genome re-sequencing (WGS) results. The phenotypic evaluation of the whole platform at seedling stage has demonstrated that the rate of variation for easily observable traits is more than 10%. The percentage of families with albino or chlorotic seedlings exceeded 3%, similar or higher to that found in other EMS collections of cucurbit crops. A rapid screening of the library for triple ethylene response in etiolated seedlings allowed the identification of four ethylene-insensitive mutants, that were found to be semidominant (ein1, ein2, and ein3) or dominant (EIN4). By evaluating 4 adult plants from 300 independent families more than 28% of apparent mutations were found for vegetative and reproductive traits, including plant vigor, leaf size and shape, sex expression and sex determination, and fruit set and development. Two pools of genomic DNA derived from 20 plants of two mutant families were subjected to WGS by using NGS methodology, estimating the density, spectrum, distribution and impact of EMS induced mutation. The number of EMS mutations in the genomes of families L1 and L2 was 1,704 and 859, respectively, which represents a density of 11.8 and 6 mutations per Mb, respectively. As expected, the predominant EMS induced mutations were C > T and G > A transitions (80.3% in L1, and 61% L2), that were found to be randomly distributed along the 20 chromosomes of C. pepo. The mutations were mostly affecting intergenic regions, but 7.9 and 6% of the identified EMS mutations in L1 and L2, respectively, were located in the exome, and 0.4 and 0.2% had a moderate and high putative impact on gene functions. These results provide information regarding the potential use of the obtained mutant platform in the discovery of novel alleles for both functional genomics and Cucurbita breeding by using direct- or reverse-genetic approaches.

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