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1.
Artigo em Inglês | MEDLINE | ID: mdl-38714264

RESUMO

The present study evaluated the effect of temporal periods of hypothermia and hyperthermia, followed by an optimal temperature recovery phase on the growth, survival, and physiological response of Penaeus vannamei. Post-larvae were exposed to stress periods for 7 and 14 days at 22 °C and 32 °C each, followed by a recovery phase at 28 °C to complete seven experimental weeks, and were compared with a control group maintained at 28 °C. Weight gain, specific growth rate, feed intake, feed conversion ratio, and survival were weekly determined. Muscle, hepatopancreas, and hemolymph were sampled on the 14th day of the recovery phase for biochemical composition, and antioxidant and digestive enzyme activities determination. The shrimp presented a higher growth rate during short-term hyperthermia in contrast to shrimp under hypothermia that presented compensatory growth after thermal stress when the temperature was restored at 28 °C. Hyperthermia increased 12-13% the feed intake while this was diminished 21-29% by the hypothermia periods. Shrimp undergo metabolic adjustments following thermal stress, with short hypothermia increasing the lipase activity and lipid storage in the hepatopancreas, while short hyperthermia also enhances chymotrypsin activity and leads to higher protein and lipid accumulation. Conversely, prolonged hyperthermia induces greater energy consumption, depleting lipid and glycogen stores, while hypothermia causes scarce mobilization of energy reserves during recovery phase. Antioxidant enzyme activities were not affected by short-thermal stress (7d), while prolonged thermal stress (14d) significantly affected SOD, CAT, and GPx activities. The present study provides important insights into the physiological plasticity of P. vannamei during recovery from thermal stress.

2.
Am Surg ; : 31348241256062, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38756087

RESUMO

Introduction: Epiploic appendagitis (EA) is an essential cause of abdominal pain that can be confused with more typical causes such as acute diverticulitis and appendicitis. Epiploic appendagitis accounts for 1% of all cases of abdominal pain in adults. The scarcity of information has limited its recognition as an essential nonsurgical cause of acute abdominal pain.Methods: We performed a systematic review of all EA cases published. We searched Scopus, Medline, Web of Science, and Google Scholar to retrieve all available studies from January 2000 to November 2023.Results: 196 case reports and case series were analyzed, with 371 patients with EA included. The mean age at the time of diagnosis was 39 years. Most patients were male (59%). The primary presenting symptoms were pain (100%), tenderness (59.5%), and rebound tenderness (27.4%). The left abdomen was the most common localization of pain (53%). The most frequently identified differential diagnoses were acute appendicitis (26.4%) and acute diverticulitis (16.1%). Most patients (53%) were treated conservatively, and 98 (26.4%) underwent surgical treatment. A significant difference in the choice of treatment was found for signs and symptoms such as rebound tenderness, nausea, anorexia, and diarrhea.Conclusions: Acute EA is an essential clinical condition of rare occurrence that might present a diagnostic challenge, as it can masquerade as another acute abdominal pain etiology. The optimal management of EA is conservative, so a higher recognition by surgeons and emergency physicians is essential to avoid unnecessary surgical interventions and their associated consequences.

3.
Pestic Biochem Physiol ; 201: 105886, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38685252

RESUMO

This study evaluates the pediculicidal activity of nanoformulations containing different binary essential oil component mixtures (eugenol:linalool, 1,8 -cineole:linalool, and eugenol:thymol) using immersion bioassays. These have allowed us to evaluate the knockdown time affecting 50% of the individuals (KT50). In addition, the type of interaction between the components in each mixture was established in terms of the combination index (IC). The KT50 values were 6.07; 8.83; 7.17 and 27.23 h for linalool, 1,8 -cineole, eugenol, and thymol, respectively. For the eugenol:linalool mixtures, the efficacy was lower or equal to that obtained for the nanoformulations of the pure compounds, with values of KT50 about 13.33, 8.16 and 6.71 h for mixtures with ratios 3:1, 1:1 and 1:3, respectively. These mixtures present IC > 1, evidencing antagonistic interaction, which is enhanced with eugenol content. In the case of the binary mixtures of 1,8 -cineole: linalool, KT50 values were similar to those obtained for eugenol:linalool mixtures with similar ratios. In this case, IC assumes values close to unity, suggesting additive interactions independently of the mixture composition. On the other side, mixtures of eugenol:thymol with 1:1 and 1:3 ratios showed values of 9.40 and 32.93 h, while the mixture with a 3:1 ratio showed the greatest effectiveness (KT50 of 4.42 h). Eugenol:thymol mixtures show synergistic interaction (IC < 1) for combinations 3:1 and 1:1, while no interaction was observed for 1:3 combination. This indicates that eugenol enhances thymol activity. These results must be considered an important step forward to the development of effective pediculicidal nanoformulations based on botanical compounds.


Assuntos
Monoterpenos Acíclicos , Eucaliptol , Eugenol , Monoterpenos , Monoterpenos/farmacologia , Monoterpenos/química , Animais , Eugenol/farmacologia , Eugenol/química , Eucaliptol/farmacologia , Monoterpenos Acíclicos/farmacologia , Monoterpenos Acíclicos/química , Pediculus/efeitos dos fármacos , Inseticidas/farmacologia , Inseticidas/química , Timol/farmacologia , Timol/química , Micelas , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Nanopartículas/química , Infestações por Piolhos/tratamento farmacológico
4.
Arch Osteoporos ; 19(1): 31, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647726

RESUMO

Reports addressing the effects of oily fish intake on bone health are inconsistent. This study shows that consumption of ≥ 5.2 oily fish servings/week (728 g) is associated with lower prevalence of osteopenia/osteoporosis in elderly women of Amerindian ancestry. Results suggest a beneficial effect of oily fish intake in this population. OBJECTIVES: Oily fish is a major dietary source of omega-3 polyunsaturated fatty acids and other nutrients that may have a positive effect on bone health. However, this association is inconsistent and seems to be more evident in certain ethnic groups. We aimed to assess the association between oily fish intake and bone mineral density (BMD) in frequent fish consumers of Amerindian ancestry living in rural Ecuador. METHODS: This study included 399 individuals aged ≥ 60 years living in three neighboring rural villages of coastal Ecuador. Dietary oily fish intake was quantified systematically using validated surveys and BMD was determined by dual-energy x-ray absorptiometry. Ordinal logistic regression models, adjusted for demographics and cardiovascular risk factors, were fitted to assess the independent association between oily fish intake and bone health. RESULTS: Participants had a mean age of 68.8 ± 6.8 years, and 58% were women. The mean intake of oily fish was 8.5 ± 4.7 servings/week, with 308 (77%) reporting high fish intake (≥ 5.2 servings/week [728 g]). Ninety-four (24%) participants had normal BMD T-scores, 149 (37%) had osteopenia, and 156 (39%) had osteoporosis. Ordinal logistic regression models showed no association between high fish intake and bone health in the total population. When men and women were analyzed separately, the association became significant for women only in both unadjusted (OR: 2.52; 95% C.I.: 1.22 - 5.23) and fully-adjusted models (OR: 2.23; 95% C.I.: 1.03 - 4.81). CONCLUSION: Consumption of ≥ 5.2 oily fish servings/week is associated with lower prevalence of osteopenia and osteoporosis in elderly women of Amerindian ancestry.


Assuntos
Densidade Óssea , Humanos , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Equador/epidemiologia , Osteoporose/epidemiologia , Osteoporose/etnologia , Animais , Peixes , Dieta/estatística & dados numéricos , Doenças Ósseas Metabólicas/epidemiologia , Óleos de Peixe/administração & dosagem , Alimentos Marinhos , População Rural/estatística & dados numéricos , Indígenas Sul-Americanos/estatística & dados numéricos , Absorciometria de Fóton
6.
Kinesiologia ; 42(4): 257-260, 20231215.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1552527

RESUMO

La comunicación efectiva en las intervenciones de fisioterapia/kinesiología tiene un impacto directo en los resultados y en la experiencia de los usuarios. Además, promover un lenguaje y una terminología universal en nuestra disciplina facilita la colaboración y la investigación nacional e internacional. El enfoque centrado en la Convención de las Naciones Unidas sobre los Derechos de las Personas con Discapacidad adoptado por la Confederación Mundial de Fisioterapia nos compromete a alinearnos con definiciones de conceptos acordados internacionalmente, lo que fortalece la profesión y promueve el profesionalismo en las acciones terapéuticas. Avanzar hacia reflexión y consensos en la comunidad de fisioterapia/kinesiología en torno a conceptos claves como discapacidad, rehabilitación, inclusión y desempeño, con la impronta del funcionamiento humano, optimizan la praxis profesional y su impacto en las intervenciones a lo largo del curso de vida en todos los niveles asistenciales.

7.
Curr Microbiol ; 80(12): 372, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37843653

RESUMO

Phage therapy is a promising alternative to control bacterial diseases and the increasing problem of antibiotic resistance. In this sense, this research evaluates the viability of lyophilized vibrio phage vB_Pd_PDCC-1 using trehalose as a preservative excipient at different concentrations (4, 2, 1, and 0.5% w/v) and its potential for phage therapy application against a pathogenic bacteria Vibrio diabolicus in brine shrimp nauplii (Artemia franciscana). The lyophilized phages were stored at 4 and 23 °C and rehydrated using biological sterile saline solution to test their viability at days 1, 15, and 60 post-lyophilization. The results showed that trehalose is beneficial in maintaining the viability of post-lyophilization phages (without titer losses) at 4 °C and even at room temperature (23 °C). When lyophilized phages with 4% w/v trehalose concentration were stored at 23 °C, they had not titer losses among the trials; viability and titer concentration were maintained up to 60 days at log 7. The use of lyophilized phage PDCC-1 increased brine shrimp survival and reduced Vibrio concentrations. The present study has identified trehalose as a promising lyophilization excipient to effectively preserve lyophilized bacteriophages for biotechnological applications and long-term storage.


Assuntos
Bacteriófagos , Vibrio , Trealose/farmacologia , Excipientes , Myoviridae
8.
Polymers (Basel) ; 15(14)2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37514401

RESUMO

This work investigates the effect of dilution on the phase separation process of binary charged polysaccharide-surfactant mixtures formed by two cationic polysaccharides and up to four surfactants of different nature (anionic, zwitterionic, and neutral), as well as the potential impact of dilution-induced phase separation on the formation of conditioning deposits on charged surfaces, mimicking the negative charge and wettability of damaged hair fibers. The results obtained showed that the dilution behavior of model washing formulations (concentrated polysaccharide-surfactant mixtures) cannot be described in terms of a classical complex precipitation framework, as phase separation phenomena occur even when the aggregates are far from the equilibrium phase separation composition. Therefore, dilution-enhanced deposition cannot be predicted in terms of the worsening of colloidal stability due to the charge neutralization phenomena, as common phase separation and, hence, enhanced deposition occurs even for highly charged complexes.

9.
Pharmaceutics ; 15(5)2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37242691

RESUMO

In recent years, the availability of effective vaccines has become a public health challenge due to the proliferation of different pandemic outbreaks which are a risk for the world population health. Therefore, the manufacturing of new formulations providing a robust immune response against specific diseases is of paramount importance. This can be partially faced by introducing vaccination systems based on nanostructured materials, and in particular, nanoassemblies obtained by the Layer-by-Layer (LbL) method. This has emerged, in recent years, as a very promising alternative for the design and optimization of effective vaccination platforms. In particular, the versatility and modularity of the LbL method provide very powerful tools for fabricating functional materials, opening new avenues on the design of different biomedical tools, including very specific vaccination platforms. Moreover, the possibility to control the shape, size, and chemical composition of the supramolecular nanoassemblies obtained by the LbL method offers new opportunities for manufacturing materials which can be administered following specific routes and present very specific targeting. Thus, it will be possible to increase the patient convenience and the efficacy of the vaccination programs. This review presents a general overview on the state of the art of the fabrication of vaccination platforms based on LbL materials, trying to highlight some important advantages offered by these systems.

10.
J Phys Condens Matter ; 35(32)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37185217

RESUMO

The association of polyelectrolytes and surfactants bearing charges of opposite signs has been for long time considered under an equilibrium framework. However, this is far to provide a true description of the physico-chemical rules of the association process when kinetically arrested nonequilibrium states are formed. This is the result of specific interaction pathways between the polyelectrolyte chains and the surfactant molecules determined by the mixing procedure and the mixture composition. In fact, the specific characteristics of the method used for the mixture can induce local inhomogeneities in the mixture composition which can govern the properties of the obtained supramolecular aggregates, driving to the systems to a situation far from the true equilibrium. This topical review tries to provide to the reader a general perspective of the role of the nonequilibrium aspects in the control of the polyelectrolyte-surfactant association process, and how these impact on the obtained supramolecular nanoassemblies, and their properties.

11.
Colloids Surf B Biointerfaces ; 227: 113341, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37210796

RESUMO

The combination of in vitro models of biological membranes based on solid-supported lipid bilayers (SLBs) and of surface sensitive techniques, such as neutron reflectometry (NR), atomic force microscopy (AFM) and quartz crystal microbalance with dissipation monitoring (QCM-D), is well suited to provide quantitative information about molecular level interactions and lipid spatial distributions. In this work, cellular plasma membranes have been mimicked by designing complex SLB, containing phosphatidylinositol 4,5-bisphosphate (PtdIns4,5P2) lipids as well as incorporating synthetic lipo-peptides that simulate the cytoplasmic tails of transmembrane proteins. The QCM-D results revealed that the adsorption and fusion kinetics of PtdIns4,5P2 are highly dependent of Mg2+. Additionally, it was shown that increasing concentrations of PtdIns4,5P2 leads to the formation of SLBs with higher homogeneity. The presence of PtdIns4,5P2 clusters was visualized by AFM. NR provided important insights about the structural organization of the various components within the SLB, highlighting that the leaflet symmetry of these SLBs is broken by the presence of CD4-derived cargo peptides. Finally, we foresee our study to be a starting point for more sophisticated in vitro models of biological membranes with the incorporation of inositol phospholipids and synthetic endocytic motifs.


Assuntos
Fosfatidilinositóis , Técnicas de Microbalança de Cristal de Quartzo , Fosfatidilinositóis/química , Técnicas de Microbalança de Cristal de Quartzo/métodos , Microscopia de Força Atômica , Bicamadas Lipídicas/química , Peptídeos/química , Nêutrons
12.
Small ; 19(36): e2302115, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37116105

RESUMO

Diffusion of biological macromolecules in the cytoplasm is a paradigm of colloidal diffusion in an environment characterized by a strong restriction of the accessible volume. This makes of the understanding of the physical rules governing colloidal diffusion under conditions mimicking the reduction in accessible volume occurring in the cell cytoplasm, a problem of a paramount importance. This work aims to study how the thermal motion of spherical colloidal beads in the inner cavity of giant unilamellar vesicles (GUVs) is modified by strong confinement conditions, and the viscoelastic character of the medium. Using single particle tracking, it is found that both the confinement and the environmental viscoelasticity lead to the emergence of anomalous motion pathways for colloidal microbeads encapsulated in the aqueous inner cavity of GUVs. This anomalous diffusion is strongly dependent on the ratio between the volume of the colloidal particle and that of the GUV under consideration as well as on the viscosity of the particle's liquid environment. Therefore, the results evidence that the reduction of the free volume accessible to colloidal motion pushes the diffusion far from a standard Brownian pathway as a result of the change in the hydrodynamic boundary conditions driving the particle motion.

13.
J Colloid Interface Sci ; 640: 220-229, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36863179

RESUMO

HYPOTHESIS: The internal organization of polyelectrolyte layers deposited on colloidal templates plays a very important role for the potential applications of these systems as capsules for drug delivery purposes. EXPERIMENTS: The mutual arrangement of oppositely charged polyelectrolyte layers upon their deposition on positively charged liposomes has been studied by combining up three different scattering techniques and Electronic Spin Resonance, which has provided information about the inter-layer interactions and their effect on the final structure of the capsules. FINDINGS: The sequential deposition of oppositely charged polyelectrolytes on the external leaflet of positively charged liposomes allows modulating the organization of the obtained supramolecular structures, impacting the packing and rigidity of the obtained capsules due to the change of the ionic cross-linking of the multi-layered film as a result of the specific charge of the last deposited layer. The possibility to modulate the properties of the LbL capsules by tuning the characteristics of the last deposited layers offers a very interesting route for the design of materials for encapsulation purposes with their properties controlled almost at will by changing the number of deposited layers and their chemistry.

14.
Int J Mol Sci ; 24(3)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36768597

RESUMO

The concentration dependence of the surface tension of several binary mixtures of non-electrolytes has been measured at 298.15 K. The mixtures have been chosen since they presented a so-called "W-shape" concentration dependence of the excess constant pressure heat capacity and high values of the concentration-concentration correlation function. This behavior was interpreted in terms of the existence of anomalously high concentration fluctuations that resemble those existing in the proximities of critical points. However, no liquid-liquid phase separation has been found in any of these mixtures over a wide temperature range. In this work, we have extended these studies to the liquid-air interfacial properties. The results show that the concentration dependence of the surface tension shows a plateau and the mixing surface tension presents a "W-shape" behavior. To the best of our knowledge, this is the first time that this behavior is reported. The weak anomalies of the surface tension near a liquid-liquid critical point suggest that the results obtained cannot be considered far-from-critical effects. The usual approach of substituting the activity by the concentration in the Gibbs equation for the relative surface concentration has been found to lead to large errors and the mixtures to have a fuzzy and thick liquid/vapor interface.


Assuntos
Temperatura Alta , Tensão Superficial
15.
J Colloid Interface Sci ; 637: 55-66, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36682118

RESUMO

HYPOTHESIS: Unravelling the structural diversity of cellular membranes is a paramount challenge in life sciences. In particular, lipid composition affects the membrane collective behaviour, and its interactions with other biological molecules. EXPERIMENTS: Here, the relationship between membrane composition and resultant structural features was investigated by surface pressure-area isotherms, Brewster angle microscopy and neutron reflectometry on in vitro membrane models of the mammalian plasma and endoplasmic-reticulum-Golgi intermediate compartment membranes in the form of Langmuir monolayers. Natural extracted yeast lipids were used because, unlike synthetic lipids, the acyl chain saturation pattern of yeast and mammalian lipids are similar. FINDINGS: The structure of the model membranes, orthogonal to the plane of the membrane, as well as their lateral packing, were found to depend strongly on their specific composition, with cholesterol having a major influence on the in-plane morphology, yielding a coexistence of liquid-order and liquid-disorder phases.


Assuntos
Microscopia , Saccharomyces cerevisiae , Animais , Membrana Celular/química , Fosfolipídeos/química , Mamíferos
17.
Microb Ecol ; 86(2): 1443-1446, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36194291

RESUMO

The protective effects of a phage cocktail composed of vB_Vc_SrVc2 and vB_Vc_SrVc9 were tested in Pacific white shrimp (Litopenaeus vannamei) postlarvae, which were originally isolated from diseased shrimps and selected due to their broad-host-range properties against several pathogenic Vibsrio species. We used culture-dependent and culture-independent approaches to explore its effect on bacterial communities associated with shrimp postlarvae. Both methods revealed that the levels of Vibrio species were significantly reduced after phage cocktail administration. Phage-treated shrimp also exhibisuppted lesser damage and higher lipid accumulation in B cells of the hepatopancreas, as revealed by histopathological examination. Taken together, this study provides clear evidence that phage therapy can selectively and effectively reduce Vibrio species, thereby providing an environmentally safe alternative to the prophylactic use of antibiotics in shrimp aquaculture.


Assuntos
Bacteriófagos , Penaeidae , Vibrio , Animais , Penaeidae/microbiologia , Aquicultura
18.
J Colloid Interface Sci ; 629(Pt B): 785-795, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36195018

RESUMO

HYPOTHESIS: Inositol phospholipids are well known to form clusters in the cytoplasmic leaflet of the plasma membrane that are responsible for the interaction and recruitment of proteins involved in key biological processes like endocytosis, ion channel activation and secondary messenger production. Although their phosphorylated inositol ring headgroup plays an important role in protein binding, its orientation with respect to the plane of the membrane and its lateral packing density has not been previously described experimentally. EXPERIMENTS: Here, we study phosphatidylinositol 4,5-bisphosphate (PIP2) planar model membranes in the form of Langmuir monolayers by surface pressure-area isotherms, Brewster angle microscopy and neutron reflectometry to elucidate the relation between lateral (in-plane) and perpendicular (out-of-plane) molecular organization of PIP2. FINDINGS: Different surface areas were explored through monolayer compression, allowing us to correlate the formation of transient PIP2 clusters with the change in orientation of the inositol-biphosphate headgroup, which was experimentally determined by neutron reflectometry.


Assuntos
Fosfatidilinositol 4,5-Difosfato , Fosfatidilinositóis , Fosfatidilinositóis/metabolismo , Fosfatidilinositol 4,5-Difosfato/química , Fosfatidilinositol 4,5-Difosfato/metabolismo , Fosfatos de Inositol/metabolismo , Membrana Celular/metabolismo , Ligação Proteica
20.
Langmuir ; 38(44): 13313-13321, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36278952

RESUMO

The interaction of particles with fluid interfaces is ubiquitous in synthetic and natural work, involving two types of interactions: particle-interface interactions (trapping energy) and interparticle interactions. Therefore, it is urgent to gain a deep understanding of the main forces controlling the trapping of particles at fluid interfaces, and their assembly to generate a broad range of structures characterized by different degrees of order. This Perspective tries to provide an overview of the main contributions to the energetic landscape controlling the assembly of particles at fluid interfaces, which is essential for exploiting this type of interfacial systems as platforms for the fabrication of interface-based soft materials with technological interest.

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