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1.
Cuad. Hosp. Clín ; 64(1): 62-66, jun. 2023.
Artigo em Espanhol | LILACS | ID: biblio-1451250

RESUMO

Los riesgos asociados a la neumonía por (SARS-CoV-2) es la generación de insuficiencia respiratoria secundaria que en algunos casos desencadenara al tan temido síndrome de distres respiratorio (SDRA); Informes sobre atención clínica, indican que tiene una incidencia (SDRA) de 3-10 % con necesidad de Asistencia Respiratoria Mecánica (ARM) en pacientes hospitalizados; por lo que dispositivos de oxigenación no invasivos siguen siendo una opción atractiva, de forma inicial. Caso clínico: mujer de 47 años con insuficiencia respiratoria secundario a neumonía por COVID-19, por la gravedad se indica su ingreso a terapia intensiva, pero por razones de falta de unidad es manejada en unidad respiratoria, con el uso de dispositivos de oxigenación de armado ARTESAL, de manera exitosa, con la utilización de CNAF-artesanal, se pretende mejorar el trabajo respiratorio, índices de oxigenación, mientras se da tratamiento a la infección por el COVID-19; el objetivo del presente caso es reportar el presente caso con evolución favorable a la literatura disponible. Discusión: El uso de terapia de oxigenación con dispositivo de Cánula Nasal de Alto Flujo, aún no ha sido normatizado en pacientes con COVID-19, pero existe evidencia clínica sobre los efectos beneficiosos en la insuficiencia respiratoria en neonatos mas no en adultos. Conclusión: El uso temprano de la CNAF-artesanal en la insuficiencia respiratoria resulta muy atractivo, más aún con dispositivo de confección artesanal, da una opción más al paciente fuera de UTI, pudiendo apoyar en evitar la intubación y su ingreso a ventilación mecánica.


The risks associated with pneumonia (SARS-CoV-2) is the generation of secondary respiratory failure that in some cases will trigger the much feared respiratory distress syndrome (ARDS); Reports on clinical care indicate that it has an incidence (ARDS) of 3-10% with the need for Mechanical Respiratory Assistance (ARM) in hospitalized patients; so non-invasive oxygenation devices remain an attractive option, initially. Clinical case: a 47-year-old woman with respiratory failure secondary to covid-19 pneumonia. Due to the severity, her admission to intensive care is indicated, but for reasons of lack of unity, she is managed in a common room, with the use of high-pressure oxygenation devices. ARTISAL assembly, successfully, with the use of CNAF-artisanal, is intended to improve the work of breathing, and oxygenation indices, while treating the infection by COVID-19; The objective of this case is to report the present case with a favorable evolution based on the available literature. Discussion: The use of oxygenation therapy with a High Flow Nasal Cannula device has not yet been standardized in patients with COVID-19, but there is clinical evidence on the beneficial effects in respiratory failure in neonates but not in adults. Conclusion: The early use of the artisan HFNC in respiratory failure is very attractive, even more so with an artisanal device, it gives the patient another option outside the ICU, being able to help avoid intubation and admission to mechanical ventilation.


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade
2.
Int J Mol Sci ; 23(13)2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35806197

RESUMO

Trans-sialidases (TS) are important constitutive macromolecules of the secretome present on the surface of Trypanosoma cruzi (T. cruzi) that play a central role as a virulence factor in Chagas disease. These enzymes have been related to infectivity, escape from immune surveillance and pathogenesis exhibited by this protozoan parasite. In this work, atomic force microscopy (AFM)-based single molecule-force spectroscopy is implemented as a suitable technique for the detection and location of functional TS on the surface of extracellular vesicles (EVs) released by tissue-culture cell-derived trypomastigotes (Ex-TcT). For that purpose, AFM cantilevers with functionalized tips bearing the anti-TS monoclonal antibody mAb 39 as a sense biomolecule are engineered using a covalent chemical ligation based on vinyl sulfonate click chemistry; a reliable, simple and efficient methodology for the molecular recognition of TS using the antibody-antigen interaction. Measurements of the breakdown forces between anti-TS mAb 39 antibodies and EVs performed to elucidate adhesion and forces involved in the recognition events demonstrate that EVs isolated from tissue-culture cell-derived trypomastigotes of T. cruzi are enriched in TS. Additionally, a mapping of the TS binding sites with submicrometer-scale resolution is provided. This work represents the first AFM-based molecular recognition study of Ex-TcT using an antibody-tethered AFM probe.


Assuntos
Vesículas Extracelulares , Parasitos , Trypanosoma cruzi , Animais , Vesículas Extracelulares/metabolismo , Glicoproteínas , Microscopia de Força Atômica , Neuraminidase/metabolismo , Parasitos/metabolismo , Trypanosoma cruzi/metabolismo
3.
Insects ; 13(6)2022 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-35735893

RESUMO

Continuous improvements in morphological and histochemical analyses of Apis mellifera could improve our understanding of the anatomy and physiology of these insects at both the cellular and tissue level. In this work, two different approaches have been performed to add new data on the abdomen of worker bees: (i) Micro-computed tomography (Micro-CT), which allows the identification of small-scale structures (micrometers) with adequate/optimal resolution and avoids sample damage and, (ii) histochemical multi-staining with Periodic Acid-Schiff-Alcian blue, Lactophenol-Saphranin O and pentachrome staining to precisely characterize the histological structures of the midgut and hindgut. Micro-CT allowed high-resolution imaging of anatomical structures of the honeybee abdomen with particular emphasis on the proventriculus and pyloric valves, as well as the connection of the sting apparatus with the terminal abdominal ganglia. Furthermore, the histochemical analyses have allowed for the first-time description of ventricular telocytes in honeybees, a cell type located underneath the midgut epithelium characterized by thin and long cytoplasmic projections called telopodes. Overall, the analysis of these images could help the detailed anatomical description of the cryptic structures of honeybees and also the characterization of changes due to abiotic or biotic stress conditions.

4.
iScience ; 24(11): 103288, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34765916

RESUMO

The shell of the cephalopod Argonauta consists of two layers of fibers that elongate perpendicular to the shell surfaces. Fibers have a high-Mg calcitic core sheathed by thin organic membranes (>100 nm) and configurate a polygonal network in cross section. Their evolution has been studied by serial sectioning with electron microscopy-associated techniques. During growth, fibers with small cross-sectional areas shrink, whereas those with large sections widen. It is proposed that fibers evolve as an emulsion between the fluid precursors of both the mineral and organic phases. When polygons reach big cross-sectional areas, they become subdivided by new membranes. To explain both the continuation of the pattern and the subdivision process, the living cells from the mineralizing tissue must perform contact recognition of the previously formed pattern and subsequent secretion at sub-micron scale. Accordingly, the fabrication of the argonaut shell proceeds by physical self-organization together with direct cellular activity.

5.
Int J Mol Sci ; 22(10)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-34068436

RESUMO

Extracellular vesicles (EVs) are small lipid vesicles released by either any prokaryotic or eukaryotic cell, or both, with a biological role in cell-to-cell communication. In this work, we characterize the proteomes and nanomechanical properties of EVs released by tissue-culture cell-derived trypomastigotes (mammalian infective stage; (TCT)) and epimastigotes (insect stage; (E)) of Trypanosoma cruzi, the etiologic agent of Chagas disease. EVs of each stage were isolated by differential centrifugation and analyzed using liquid chromatography with tandem mass spectrometry (LC-MS/MS), dynamic light scattering (DLS), nanoparticle tracking analysis (NTA), electron microscopy and atomic force microscopy (AFM). Measurements of zeta-potential were also included. Results show marked differences in the surface molecular cargos of EVs between both stages, with a noteworthy expansion of all groups of trans-sialidase proteins in trypomastigote's EVs. In contrast, chromosomal locations of trans-sialidases of EVs of epimastigotes were dramatically reduced and restricted to subtelomeric regions, indicating a possible regulatable expression of these proteins between both stages of the parasite. Regarding mechanical properties, EVs of trypomastigotes showed higher adhesion compared to the EVs of epimastigotes. These findings demonstrate the remarkable surface remodeling throughout the life cycle of T. cruzi, which shapes the physicochemical composition of the extracellular vesicles and could have an impact in the ability of these vesicles to participate in cell communication in completely different niches of infection.


Assuntos
Doença de Chagas/metabolismo , Vesículas Extracelulares/metabolismo , Estágios do Ciclo de Vida , Proteoma/metabolismo , Proteínas de Protozoários/metabolismo , Trypanosoma cruzi/metabolismo , Animais , Doença de Chagas/parasitologia , Chlorocebus aethiops , Vesículas Extracelulares/parasitologia , Interações Hospedeiro-Parasita , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Proteoma/análise , Células Vero
6.
J R Soc Interface ; 17(170): 20200505, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32993433

RESUMO

The vesicular microstructure is a very distinctive arrangement of calcite, consisting of hollow cavities (vesicles) of diverse sizes and shapes, usually elongated in the direction of shell thickening. It is uniquely found among living bivalves in a single oyster family, Gryphaeidae. The vesicles are distributed in lenses interleaved with compact foliated layers. We have studied the morphology and distribution of vesicles within the lenses using optical and electron microscopy, and micro-computed tomography. At a small scale, vesicles do not follow a classical von Neumann-Mullins route typical of ideal foams. At a larger scale, the initiation and evolution of a vesicular layer statistically proceed like a foam, with vesicles becoming more numerous, larger and more even in size. In summary, the vesicular material follows a foam-like coarsening to reduce the number of energetically costly interfaces. However, a steady state is never reached because the animal permanently introduces energy in the system by creating new vesicles. The fabrication of the vesicular material is mediated by the production of an emulsion between the extrapallial fluid and the precursor PILP of the calcitic walls within the thin extrapallial space. For this mechanism to proceed, the mantle cells must perform highly sophisticated behaviours of contact recognition and secretion. Accordingly, the vesicular material is under mixed physical-biological control.


Assuntos
Bivalves , Ostreidae , Animais , Carbonato de Cálcio , Microscopia Eletrônica de Varredura , Microtomografia por Raio-X
7.
Pathogens ; 9(2)2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32098034

RESUMO

Acanthamoeba is a genus of free-living amoebae widely distributed in nature, associated with the development of encephalitis and keratitis. Despite the fact that it is common to find genotype T5 in environmental samples, only a few cases have been associated with clinical cases in humans. The wide distribution of Acanthamoeba, the characteristic of being amphizoic and the severity of the disease motivate researchers to focus on the isolation of these organisms, but also in demonstrating direct and indirect factors that could indicate a possible pathogenic potential. Here, we performed the characterization of the pathogenic potential of an Acanthamoeba T5 isolate collected from a water source in a hospital. Osmo- and thermotolerance, the secretion of proteases and the effect of trophozoites over cell monolayers were analyzed by different methodologies. Additionally, we confirm the secretion of extracellular vesicles (EVs) of this isolate incubated at two different temperatures, and the presence of serine and cysteine proteases in these vesicles. Finally, using atomic force microscopy, we determined some nanomechanical properties of the secreted vesicles and found a higher value of adhesion in the EVs obtained at 37 °C, which could have implications in the parasite´s survival and damaging potential in two different biological environments.

8.
Chem Sci ; 10(4): 1126-1137, 2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30774910

RESUMO

DNA molecules containing a 1D silver array may be applied for nanotechnology applications, but first their conducting and photoluminescence behavior must be enhanced. Here we have synthesized and characterized three new helical compounds based on stacked silver-mediated cytosine base pairs [Ag(mC)2]X (mC = N1-methylcytosine; X = NO3 (1), BF4 (2) and ClO4 (3)), that contain uninterrupted polymeric AgI chains that run through the center of the helixes, comparable to related silver-DNA structures. The exposure of nanostructures of [Ag(mC)2]BF4 (2) to cold hydrogen plasma stimulates the reduction of the prearranged AgI polymeric chains to metallic silver along the material. This solvent-free reduction strategy leads to the compound [AgI(mC)2]X@Ag0 (2H) that contains uniformly well-distributed silver metallic nanostructures that are responsible for the new conducting and photoluminescence properties of the material. The presence of silver nanostructures alongside compound 2H has been evaluated by means of X-ray photoelectron spectroscopy (XPS), UV-vis spectroscopy, and X-ray powder diffraction (XRPD). The conducting and photoactive properties of 2H were studied by electrostatic force microscopy (EFM) and conducting-AFM (c-AFM), and photoluminescence microscopy (PL), respectively. The results demonstrate that the presence of well-organized metallic silver nanoentities on the material is responsible for the novel conductivity and photoactive properties of the material. This methodology can be employed for the generation of multifunctional silver-DNA related materials with tailored properties.

9.
PLoS One ; 13(3): e0194353, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29566022

RESUMO

The substitution of fish resources as ingredients for aquafeeds by those based on vegetable sources is needed to ensure aquaculture sustainability in the future. It is known that Senegalese sole (Solea senegalensis) accepts high dietary content of plant ingredients without altering growth or flesh quality parameters. However, scarce information is available regarding the long-term impact of vegetable diets (combining the inclusion of both vegetable protein and oils) on the stress response and immunity of this fish species. This study aims to evaluate the concomitant effect of the extended use of vegetable protein-based diets with fish oil (FO) replacement (0, 50 or 100%) by vegetable oils (VO), on the response to acute (10 min) or prolonged (4 days) stress, induced by thermal shock. Plasma levels of cortisol, glucose and lactate as well as hepatic levels of glucose, glycogen and lactate were evaluated as primary and secondary responses to stress, 6 and 18 months after feeding the experimental diets (6 and 18 MAF). The brain monoaminergic activity in telencephalon and hypothalamus, and non-specific immune parameters were also evaluated. As expected, thermal shock induced an increase in values of plasma parameters related to stress, which was more evident in acute than in prolonged stress. Stress also affected lactate levels in the liver and the values of the alternative complement pathway-ACH50 in the plasma. Dietary substitution of FO induced an effect per se on some parameters such as decreased hepatic glucose and glycogen levels and peroxidase activity in plasma as well enhanced serotonergic activity in brain of non-stressed fish. The results obtained in some parameters indicate that there is an interaction between the use of vegetable diets with the physiological response to thermal stress, as is the case of the hepatic lactate, serotonergic neurotransmission in brain, and the activity of ACH50 in plasma. These results suggest that the inclusion of VO in plant protein based diets point to a slightly inhibited stress response, more evident for an acute than a prolonged stress.


Assuntos
Ração Animal/análise , Linguados/fisiologia , Óleos de Plantas/administração & dosagem , Proteínas de Vegetais Comestíveis/administração & dosagem , Estresse Fisiológico , Animais , Aquicultura , Glicemia/análise , Linguados/sangue , Linguados/imunologia , Hidrocortisona/sangue , Hidrocortisona/metabolismo , Ácido Láctico/sangue , Ácido Láctico/metabolismo , Fígado/química , Temperatura , Verduras/química , Verduras/metabolismo
10.
Chem Commun (Camb) ; 47(42): 11751-3, 2011 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-21952589

RESUMO

The highly porous and robust [Ni(8)(OH)(4)(OH(2))(2)(4,4'-(buta-1,3-diyne-1,4-diyl)bispyrazolato)(6)](n) MOF can be used as a proof of concept for the incorporation and release of the non-conventional [Ru(p-cymene)Cl(2)(pta)] RAPTA-C metallodrug.


Assuntos
Antineoplásicos/química , Compostos Organometálicos/química , Rutênio/química , Cimenos
11.
J Am Chem Soc ; 133(31): 11888-91, 2011 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-21761835

RESUMO

In this communication, a series of observations and data analyses coherently confirms the suitability of the novel metal-organic framework (MOF) [Zn(4)(µ(4)-O)(µ(4)-4-carboxy-3,5-dimethyl-4-carboxy-pyrazolato)(3)] (1) in the capture of harmful volatile organic compounds (VOCs). It is worthy of attention that 1, whose crystal structure resembles that of MOF-5, exhibits remarkable thermal, mechanical, and chemical stability, as required if practical applications are sought. In addition, it selectively captures harmful VOCs (including models of Sarin and mustard gas, which are chemical warfare agents), even in competition with ambient moisture (i.e., under conditions mimicking operative ones). The results can be rationalized on the basis of Henry constant and adsorption heat values for the different essayed adsorbates as well as H(2)O/VOC partition coefficients as obtained from variable-temperature reverse gas chromatography experiments. To further strengthen the importance of 1, its performance in the capture of harmful VOCs has been compared with those of well-known materials, namely, a MOF with coordinatively unsaturated metal sites, [Cu(3)(btc)(2)] and the molecular sieve active carbon Carboxen. The results of this comparison show that coordinatively unsaturated metal sites (preferential guest-binding sites) are ineffective for the capture of VOCs in the presence of ambient moisture. Consequently, we propose that the driving force of the VOC-MOF recognition process is mainly dictated by pore size and surface hydrophobicity.


Assuntos
Substâncias para a Guerra Química/química , Compostos Organometálicos/química , Compostos Orgânicos Voláteis/química , Interações Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Estrutura Molecular
13.
J Anim Physiol Anim Nutr (Berl) ; 94(2): 212-9, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19175453

RESUMO

Rearing blackspot seabream has been associated with low growth rates and excessive lipid accumulation, resulting in a reduction of the edible yield. The effect of extruded diets containing different carbohydrate sources (wheat vs. wheat bran) was evaluated on 100 g blackspot seabream growth performance, feed utilization and fat deposition, taking into consideration the optimal dietary protein and lipid level described for smaller-sized fish. A fish meal-based diet was also tested as a control to assure maximal growth rates were achieved. The experiment was held in sea cages at environmental conditions. Duplicate groups of fish were distributed among six cages with a stocking density of 1.3 kg/m(3) and hand-fed each diet for 7 months. At the end of the experiment, fish in all groups doubled their body weight attaining 190-230 g. Specific growth rate (0.3-04), feed conversion ratio (1.3-1.6) and protein gain (0.5-0.6 g/kg/day) were similar among treatments. The Hepatosomatic Index, the Viscerosomatic Index and final whole body composition did not vary significantly among dietary treatments; nevertheless, the inclusion of wheat bran induced a significant increase of liver lipid content and the highest mesenteric fat index. All diets were effective in reducing whole body and mesenteric fat compared with initial values.


Assuntos
Composição Corporal/efeitos dos fármacos , Carboidratos da Dieta/farmacologia , Lipídeos/análise , Dourada/crescimento & desenvolvimento , Dourada/fisiologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Fibras na Dieta , Esquema de Medicação , Metabolismo dos Lipídeos , Triticum
14.
Inorg Chem ; 48(15): 7413-20, 2009 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-19586019

RESUMO

The reaction of [(cymene)RuCl(2)](2) with K(2)Hoxonate (H(3)oxonic = 4,6-dihydroxy-2-carboxy-1,3,5-triazine acid) in methanol leads to the formation of the dinuclear half-sandwich ruthenium(II) complex [(cymene)(2)Ru(2)(mu-Hoxonato)Cl(2)] (1a). Removal of the chloride ligands of 1a by treatment with AgCF(3)SO(3) yields [(cymene)(2)Ru(2)(mu-Hoxonato)(CF(3)SO(3))(2)] (1b), which, upon posterior reaction with N,N'-linkers (L = 4,4'-bipyridine (4,4'-bpy), 4,7-phenantroline (4,7-phen)), gives rise to the formation of the tetranuclear open boxes [(cymene)(4)Ru(4)(mu-Hoxonato)(2)(mu-N,N'-L)(2)](CF(3)SO(3))(4) (2a, L = 4,4'-bpy; 2b, L = 4,7-phen). These systems have been characterized by (1)H NMR, UV-vis, and ESI-MS. The single-crystal structures of the dinuclear precursor 1a and of the clathrate 2b 4,7-phen have been determined. The interaction of these systems with cysteine, mononucleotides, and calf-thymus DNA has been studied by means of (1)H NMR, UV-vis, circular dicroism, competitive binding assays, and atomic force microscopy imaging. The results show that the robust tetracationic ruthenium(II) cyclic systems 2a and 2b do not give ligand exchange reactions toward biorelevant ligands. Nevertheless, these systems are able to noncovalently bind to DNA, probably at the surface of the major groove, inducing significant conformational changes in this biomolecule. It is also interesting to note that compounds 2a and 2b, in spite of only giving supramolecular interactions with biomolecules, exhibit antitumor activity, particularly toward the human ovarian cancer cell line A2780cisR, showing acquired resistance to cisplatin, with respective 4.6 and 8.3 microM IC(50) values.


Assuntos
DNA/química , Compostos de Rutênio/química , Compostos de Rutênio/farmacologia , Animais , Bovinos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cristalografia por Raios X , DNA/ultraestrutura , Humanos , Microscopia de Força Atômica , Modelos Moleculares , Estrutura Molecular , Compostos de Rutênio/síntese química
15.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 1): m86-7, 2009 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-21579978

RESUMO

The two independent Mn(II) ions in the polymeric title compound, {[Mn(2)(C(6)H(2)N(2)O(4))(C(10)H(8)N(2))(H(2)O)(6)]SO(4)·3H(2)O}, exhibit distorted MnN(2)O(4) octa-hedral coordination geometries, with the pyrimidine-4,6-dicarboxyl-ate (pmdc) ligand acting in the bis-chelating µ-(κO,κN:κO',κN') bridging mode and the 4,4'-bipyridine (bpy) ligand in the µ-(κN:κN') bridging mode. The remaining coordination sites are occupied by O atoms of water mol-ecules. As a consequence, cationic chains of [Mn(2)(µ-pmdc)(µ-4,4'-bpy)(H(2)O)(6)](2+) are generated, which extend approximately along the a axis. Sulfate counter-anions and three uncoordinated water mol-ecules complete the structure, which is stabilized by multiple O-H⋯O hydrogen-bonding inter-actions between the structural units.

16.
Chem Commun (Camb) ; (32): 3735-7, 2008 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-18685760

RESUMO

The cyclic trinuclear system, [(en)(3)Pd(3)(4,7-phen)(3)](6+), undergoes a ligand exchange reaction with 5-R-2-hydroxypyrimidine derivatives (HRpymo; R = ethynylferrocene, 5-(dimethylamino)-N-(2-propynyl)-1-naphthalene sulfonamide) to give [(en)(3)Pd(3)(4,7-phen)(2)(Rpymo)](5+), functional supramolecular receptors of mononucleotides.

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